EPAS1 Attenuates Atherosclerosis Initiation at Disturbed Flow Sites Through Endothelial Fatty Acid Uptake.

BACKGROUND: Atherosclerotic plaques form unevenly due to disturbed blood flow, causing localized endothelial cell (EC) dysfunction. Obesity exacerbates this process, but the underlying molecular mechanisms are unclear. The transcription factor EPAS1 (HIF2A) has regulatory roles in endothelium, but its involvement in atherosclerosis remains unexplored. This study investigates the potential interplay between EPAS1, obesity, and atherosclerosis. METHODS: Responses to shear stress were analyzed using cultured porcine aortic EC exposed to flow in vitro coupled with metabolic and molecular analyses and by en face immunostaining of murine aortic EC exposed to disturbed flow in vivo. Obesity and dyslipidemia were induced in mice via exposure to a high-fat diet or through Leptin gene deletion. The role of Epas1 in atherosclerosis was evaluated by inducible endothelial Epas1 deletion, followed by hypercholesterolemia induction (adeno-associated virus-PCSK9 [proprotein convertase subtilisin/kexin type 9]; high-fat diet). RESULTS: En face staining revealed EPAS1 enrichment at sites of disturbed blood flow that are prone to atherosclerosis initiation. Obese mice exhibited substantial reduction in endothelial EPAS1 expression. Sulforaphane, a compound with known atheroprotective effects, restored EPAS1 expression and concurrently reduced plasma triglyceride levels in obese mice. Consistently, triglyceride derivatives (free fatty acids) suppressed EPAS1 in cultured EC by upregulating the negative regulator PHD2. Clinical observations revealed that reduced serum EPAS1 correlated with increased endothelial PHD2 and PHD3 in obese individuals. Functionally, endothelial EPAS1 deletion increased lesion formation in hypercholesterolemic mice, indicating an atheroprotective function. Mechanistic insights revealed that EPAS1 protects arteries by maintaining endothelial proliferation by positively regulating the expression of the fatty acid-handling molecules CD36 (cluster of differentiation 36) and LIPG (endothelial type lipase G) to increase fatty acid beta-oxidation. CONCLUSIONS: Endothelial EPAS1 attenuates atherosclerosis at sites of disturbed flow by maintaining EC proliferation via fatty acid uptake and metabolism. This endothelial repair pathway is inhibited in obesity, suggesting a novel triglyceride-PHD2 modulation pathway suppressing EPAS1 expression. These findings have implications for therapeutic strategies addressing vascular dysfunction in obesity.

Anthocyanins in Vascular Health and Disease: Mechanisms of Action and Therapeutic Potential.

ABSTRACT: Unhealthy lifestyles have placed a significant burden on individuals' cardiovascular health. Anthocyanins are water-soluble flavonoid pigments found in a wide array of common foods and fruits. Anthocyanins have the potential to contribute to the prevention and treatment of cardiovascular disease by improving lipid profiles and vascular function, reducing blood glucose levels and blood pressure, and inhibiting inflammation. These actions have been demonstrated in numerous clinical and preclinical studies. At the cellular and molecular level, anthocyanins and their metabolites could protect endothelial cells from senescence, apoptosis, and inflammation by activating the phosphoinositide 3-kinase/protein kinase B/endothelial nitric oxide synthases, silent information regulator 1 (SIRT1), or nuclear factor erythroid2-related factor 2 pathways and inhibiting the nuclear factor kappa B, Bax, or P38 mitogen-activated protein kinase pathways. Furthermore, anthocyanins prevent vascular smooth muscle cell from platelet-derived growth factor -induced or tumor necrosis factor-α-induced proliferation and migration by inhibiting the focal adhesion kinase and extracellular regulated protein kinases signaling pathways. Anthocyanins could also attenuate vascular inflammation by reducing the formation of oxidized lipids, preventing leukocyte adhesion and infiltration of the vessel wall, and macrophage phagocytosis of deposited lipids through reducing the expression of cluster of differentiation 36 and increasing the expression of ATP-binding cassette subfamily A member 1 and ATP-binding cassette subfamily G member 1. At the same time, anthocyanins could lower the risk of thrombosis by inhibiting platelet activation and aggregation through down-regulating P-selectin, transforming growth factor-1, and CD40L. Thus, the development of anthocyanin-based supplements or derivative drugs could provide new therapeutic approaches to the prevention and treatment of vascular diseases.

Urolithin A promotes atherosclerotic plaque stability by limiting inflammation and hypercholesteremia in Apolipoprotein E-deficient mice.

Urolithin A (UroA), a dietary phytochemical, is produced by gut bacteria from fruits rich in natural polyphenols ellagitannins (ETs). The efficiency of ETs metabolism to UroA in humans depends on gut microbiota. UroA has shown a variety of pharmacological activities. In this study we investigated the effects of UroA on atherosclerotic lesion development and stability. Apolipoprotein E-deficient (ApoE-/-) mice were fed a high-fat and high-cholesterol diet for 3 months to establish atherosclerosis model. Meanwhile the mice were administered UroA (50 mg·kg-1·d-1, i.g.). We showed that UroA administration significantly decreased diet-induced atherosclerotic lesions in brachiocephalic arteries, macrophage content in plaques, expression of endothelial adhesion molecules, intraplaque hemorrhage and size of necrotic core, while increased the expression of smooth muscle actin and the thickness of fibrous cap, implying features of plaque stabilization. The underlying mechanisms were elucidated using TNF-α-stimulated human endothelial cells. Pretreatment with UroA (10, 25, 50 µM) dose-dependently inhibited TNF-α-induced endothelial cell activation and monocyte adhesion. However, the anti-inflammatory effects of UroA in TNF-α-stimulated human umbilical vein endothelial cells (HUVECs) were independent of NF-κB p65 pathway. We conducted RNA-sequencing profiling analysis to identify the differential expression of genes (DEGs) associated with vascular function, inflammatory responses, cell adhesion and thrombosis in UroA-pretreated HUVECs. Human disease enrichment analysis revealed that the DEGs were significantly correlated with cardiovascular diseases. We demonstrated that UroA pretreatment mitigated endothelial inflammation by promoting NO production and decreasing YAP/TAZ protein expression and TEAD transcriptional activity in TNF-α-stimulated HUVECs. On the other hand, we found that UroA administration modulated the transcription and cleavage of lipogenic transcription factors SREBP1/2 in the liver to ameliorate cholesterol metabolism in ApoE-/- mice. This study provides an experimental basis for new dietary therapeutic option to prevent atherosclerosis.

Predicting cytopenias, progression, and survival in patients with clonal cytopenia of undetermined significance: a prospective cohort study.

BACKGROUND: Somatic mutations are frequently reported in individuals with cytopenia but without a confirmed haematological diagnosis (clonal cytopenia of undetermined significance; CCUS). These patients have an increased risk of progression to a myeloid malignancy and worse overall survival than those with no such mutations. To date, studies have been limited by retrospective analysis or small patient numbers. We aimed to establish the natural history of CCUS by prospectively investigating outcome in a large, well defined patient cohort. METHODS: This prospective cohort study was conducted at the Haematological Malignancy Diagnostic Service, a diagnostic laboratory in Leeds, UK. Patients aged at least 18 years who were referred for investigation of cytopenia were eligible for inclusion; those with a history of myeloid malignancy were not eligible. Targeted sequencing was conducted alongside routine clinical testing. Baseline mutation analysis was then correlated with the main study outcomes: longitudinal blood counts, disease progression to a myeloid malignancy, and overall survival with a median follow-up of 4·54 years (IQR 4·03-5·04). Data were collected manually from hospital records or extracted from laboratory or clinical outcome databases. FINDINGS: Bone marrow samples from 2348 patients were received at the Haematological Malignancy Diagnostic Service between July 1, 2014, and July 31, 2016. Of these, 2083 patients (median age 72 years [IQR 63-80, range 18-99]; 854 [41·0%] female and 1229 [59·0%] male) met the inclusion criteria and had samples of sufficient quality for further analysis. 598 (28·7%) patients received a diagnosis on the basis of their biopsy sample, whereas 1485 (71·3%) samples were classified as non-diagnostic; of these, CCUS was confirmed in 400 (26·9%) patients (256 [64·0%] male and 144 [36·0%] female). TET2, SRSF2, and DNMT3A were the most frequently mutated genes in patients with CCUS, with 320 (80%) of 400 patients harbouring a mutation in at least one of these genes. Age (p<0·0001), sex (p=0·0027), and mutations in ASXL1 (p=0·0009), BCOR (p=0·0056), and TP53 (p=0·0055) correlated with a worse overall survival; however, the number of mutations was the strongest predictor for progression to a myeloid malignancy (two mutations, p=0·0024; three or more mutations, p=0·0004). Extended sequencing of samples from a subgroup of patients with sequential samples and no mutations in the initial myeloid gene panel showed recurrent mutations in both DDX41 and UBA1, suggesting that these genes should be included in clinical test panels. INTERPRETATION: Mutation analysis is advised in patients who have undergone bone marrow examination and have an otherwise-unexplained cytopenia. High-risk genetic mutations and increased numbers of mutations are predictive of both survival and progression within 5 years of presentation, warranting clinical surveillance and, when necessary, intervention. FUNDING: MDS Foundation.

Panguiarchaeum symbiosum, a potential hyperthermophilic symbiont in the TACK superphylum.

The biology of Korarchaeia remains elusive due to the lack of genome representatives. Here, we reconstruct 10 closely related metagenome-assembled genomes from hot spring habitats and place them into a single species, proposed herein as Panguiarchaeum symbiosum. Functional investigation suggests that Panguiarchaeum symbiosum is strictly anaerobic and grows exclusively in thermal habitats by fermenting peptides coupled with sulfide and hydrogen production to dispose of electrons. Due to its inability to biosynthesize archaeal membranes, amino acids, and purines, this species likely exists in a symbiotic lifestyle similar to DPANN archaea. Population metagenomics and metatranscriptomic analyses demonstrated that genes associated with amino acid/peptide uptake and cell attachment exhibited positive selection and were highly expressed, supporting the proposed proteolytic catabolism and symbiotic lifestyle. Our study sheds light on the metabolism, evolution, and potential symbiotic lifestyle of Panguiarchaeum symbiosum, which may be a unique host-dependent archaeon within the TACK superphylum.

Optimising care for UK patients with acute myeloid leukaemia.

Acute myeloid leukaemia is a rare cancer, with about 3000 cases diagnosed each year in the UK. Diagnosis is based on patient history, blood and bone marrow tests and, in some cases, imaging. Chemotherapy is the mainstay of treatment for acute myeloid leukaemia, with eligible patients also undergoing allogeneic haematopoietic stem cell transplantation, which can be curative. However, patients must be carefully evaluated by the multidisciplinary team before they are put forward for transplant to ensure they are able to tolerate the conditioning therapy required. Improvements in transplant technology have increased donor availability and reduced transplant toxicity. At the same time, greater understanding of the cytogenetics and molecular genetics of acute myeloid leukaemia have helped to ensure that patients receive treatment that gives them the best chance of survival. A recent roundtable discussion considered how current diagnostic and treatment pathways might be adapted or enhanced to leverage good outcomes for the greatest numbers of patients.

Low-temperature nanoscale heat transport in a gadolinium iron garnet heterostructure probed by ultrafast x-ray diffraction.

Time-resolved x-ray diffraction has been used to measure the low-temperature thermal transport properties of a Pt/Gd3Fe5O12//Gd3Ga5O12 metal/oxide heterostructure relevant to applications in spin caloritronics. A pulsed femtosecond optical signal produces a rapid temperature rise in the Pt layer, followed by heat transport into the Gd3Fe5O12 (GdIG) thin film and the Gd3Ga5O12 (GGG) substrate. The time dependence of x-ray diffraction from the GdIG layer was tracked using an accelerator-based femtosecond x-ray source. The ultrafast diffraction measurements probed the intensity of the GdIG (1 -1 2) x-ray reflection in a grazing-incidence x-ray diffraction geometry. The comparison of the variation of the diffracted x-ray intensity with a model including heat transport and the temperature dependence of the GdIG lattice parameter allows the thermal conductance of the Pt/GdIG and GdIG//GGG interfaces to be determined. Complementary synchrotron x-ray diffraction studies of the low-temperature thermal expansion properties of the GdIG layer provide a precise calibration of the temperature dependence of the GdIG lattice parameter. The interfacial thermal conductance of the Pt/GdIG and GdIG//GGG interfaces determined from the time-resolved diffraction study is of the same order of magnitude as previous reports for metal/oxide and epitaxial dielectric interfaces. The thermal parameters of the Pt/GdIG//GGG heterostructure will aid in the design and implementation of thermal transport devices and nanostructures.

Epigenetic regulator genes direct lineage switching in MLL/AF4 leukemia.

The fusion gene MLL/AF4 defines a high-risk subtype of pro-B acute lymphoblastic leukemia. Relapse can be associated with a lineage switch from acute lymphoblastic to acute myeloid leukemia, resulting in poor clinical outcomes caused by resistance to chemotherapies and immunotherapies. In this study, the myeloid relapses shared oncogene fusion breakpoints with their matched lymphoid presentations and originated from various differentiation stages from immature progenitors through to committed B-cell precursors. Lineage switching is linked to substantial changes in chromatin accessibility and rewiring of transcriptional programs, including alternative splicing. These findings indicate that the execution and maintenance of lymphoid lineage differentiation is impaired. The relapsed myeloid phenotype is recurrently associated with the altered expression, splicing, or mutation of chromatin modifiers, including CHD4 coding for the ATPase/helicase of the nucleosome remodelling and deacetylation complex. Perturbation of CHD4 alone or in combination with other mutated epigenetic modifiers induces myeloid gene expression in MLL/AF4+ cell models, indicating that lineage switching in MLL/AF4 leukemia is driven and maintained by disrupted epigenetic regulation.

Cezanne is a critical regulator of pathological arterial remodelling by targeting ß-catenin signalling.

AIMS: Pathological arterial remodelling including neointimal hyperplasia and atherosclerosis is the main underlying cause for occluding arterial diseases. Cezanne is a novel deubiquitinating enzyme, functioning as a NF-кB negative regulator, and plays a key role in renal inflammatory response and kidney injury induced by ischaemia. Here we attempted to examine its pathological role in vascular smooth muscle cell (VSMC) pathology and arterial remodelling. METHODS AND RESULTS: Cezanne expression levels were consistently induced by various atherogenic stimuli in VSMCs, and in remodelled arteries upon injury. Functionally, VSMCs over-expressing wild-type Cezanne, but not the mutated catalytically-inactive Cezanne (C209S), had an increased proliferative ability and mobility, while the opposite was observed in VSMCs with Cezanne knockdown. Surprisingly, we observed no significant effects of Cezanne on VSMC apoptosis, NF-κB signalling, or inflammation. RNA-sequencing and biochemical studies showed that Cezanne drives VSMC proliferation by regulating CCN family member 1 (CCN1) by targeting ß-catenin for deubiquitination. Importantly, local correction of Cezanne expression in the injured arteries greatly decreased VSMC proliferation, and prevented arterial inward remodelling. Interestingly, global Cezanne gene deletion in mice led to smaller atherosclerotic plaques, but with a lower level of plaque stability. Translating, we observed a similar role for Cezanne in human VSMCs, and higher expression levels of Cezanne in human atherosclerotic lesions. CONCLUSION: Cezanne is a key regulator of VSMC proliferation and migration in pathological arterial remodelling. Our findings have important implications for therapeutic targeting Cezanne signalling and VSMC pathology in vascular diseases.

Resilience of the Internal Mammary Artery to Atherogenesis: Shifting From Risk to Resistance to Address Unmet Needs.

Fueled by the global surge in aging, atherosclerotic cardiovascular disease reached pandemic dimensions putting affected individuals at enhanced risk of myocardial infarction, stroke, and premature death. Atherosclerosis is a systemic disease driven by a wide spectrum of factors, including cholesterol, pressure, and disturbed flow. Although all arterial beds encounter a similar atherogenic milieu, the development of atheromatous lesions occurs discontinuously across the vascular system. Indeed, the internal mammary artery possesses unique biological properties that confer protection to intimal growth and atherosclerotic plaque formation, thus making it a conduit of choice for coronary artery bypass grafting. Its endothelium abundantly expresses nitric oxide synthase and shows accentuated nitric oxide release, while its vascular smooth muscle cells exhibit reduced tissue factor expression, high tPA (tissue-type plasminogen activator) production and blunted migration and proliferation, which may collectively mitigate intimal thickening and ultimately the evolution of atheromatous plaques. We aim here to provide insights into the anatomy, physiology, cellular, and molecular aspects of the internal mammary artery thereby elucidating its remarkable resistance to atherogenesis. We propose a change in perspective from risk to resilience to decipher mechanisms of atheroresistance and eventually identification of novel therapeutic targets presently not addressed by currently available remedies.

Progress in cardiac research: from rebooting cardiac regeneration to a complete cell atlas of the heart.

We review some of the important discoveries and advances made in basic and translational cardiac research in 2020. For example, in the field of myocardial infarction (MI), new aspects of autophagy and the importance of eosinophils were described. Novel approaches, such as a glycocalyx mimetic, were used to improve cardiac recovery following MI. The strategy of 3D bio-printing was shown to allow the fabrication of a chambered cardiac organoid. The benefit of combining tissue engineering with paracrine therapy to heal injured myocardium is discussed. We highlight the importance of cell-to-cell communication, in particular, the relevance of extracellular vesicles, such as exosomes, which transport proteins, lipids, non-coding RNAs, and mRNAs and actively contribute to angiogenesis and myocardial regeneration. In this rapidly growing field, new strategies were developed to stimulate the release of reparative exosomes in ischaemic myocardium. Single-cell sequencing technology is causing a revolution in the study of transcriptional expression at cellular resolution, revealing unanticipated heterogeneity within cardiomyocytes, pericytes and fibroblasts, and revealing a unique subpopulation of cardiac fibroblasts. Several studies demonstrated that exosome- and non-coding RNA-mediated approaches can enhance human induced pluripotent stem cell (iPSC) viability and differentiation into mature cardiomyocytes. Important details of the mitochondrial Ca2+ uniporter and its relevance were elucidated. Novel aspects of cancer therapeutic-induced cardiotoxicity were described, such as the novel circular RNA circITCH, which may lead to novel treatments. Finally, we provide some insights into the effects of SARS-CoV-2 on the heart.

Evaluation of a worldwide EQA scheme for complex clonality analysis of clinical lymphoproliferative cases demonstrates a learning effect.

Clonality analysis of immunoglobulin (IG) or T-cell receptor (TR) gene rearrangements is routine practice to assist diagnosis of lymphoid malignancies. Participation in external quality assessment (EQA) aids laboratories in identifying systematic shortcomings. The aim of this study was to evaluate laboratories' improvement in IG/TR analysis and interpretation during five EQA rounds between 2014 and 2018. Each year, participants received a total of five cases for IG and five cases for TR testing. Paper-based cases were included for analysis of the final molecular conclusion that should be interpreted based on the integration of the individual PCR results. Wet cases were distributed for analysis of their routine protocol as well as evaluation of the final molecular conclusion. In total, 94.9% (506/533) of wet tests and 97.9% (829/847) of paper tests were correctly analyzed for IG, and 96.8% (507/524) wet tests and 93.2% (765/821) paper tests were correctly analyzed for TR. Analysis scores significantly improved when laboratories participated to more EQA rounds (p=0.001). Overall performance was significantly lower (p=0.008) for non-EuroClonality laboratories (95% for IG and 93% for TR) compared to EuroClonality laboratories (99% for IG and 97% for TR). The difference was not related to the EQA scheme year, anatomic origin of the sample, or final clinical diagnosis. This evaluation showed that repeated EQA participation helps to reduce performance differences between laboratories (EuroClonality versus non-EuroClonality) and between sample types (paper versus wet). The difficulties in interpreting oligoclonal cases highlighted the need for continued education by meetings and EQA schemes.

Genome-wide association study identifies risk loci for progressive chronic lymphocytic leukemia.

Prognostication in patients with chronic lymphocytic leukemia (CLL) is challenging due to heterogeneity in clinical course. We hypothesize that constitutional genetic variation affects disease progression and could aid prognostication. Pooling data from seven studies incorporating 842 cases identifies two genomic locations associated with time from diagnosis to treatment, including 10q26.13 (rs736456, hazard ratio (HR) = 1.78, 95% confidence interval (CI) = 1.47-2.15; P = 2.71 × 10-9) and 6p (rs3778076, HR = 1.99, 95% CI = 1.55-2.55; P = 5.08 × 10-8), which are particularly powerful prognostic markers in patients with early stage CLL otherwise characterized by low-risk features. Expression quantitative trait loci analysis identifies putative functional genes implicated in modulating B-cell receptor or innate immune responses, key pathways in CLL pathogenesis. In this work we identify rs736456 and rs3778076 as prognostic in CLL, demonstrating that disease progression is determined by constitutional genetic variation as well as known somatic drivers.

Synthesis and optimisation of P3 substituted vinyl sulfone-based inhibitors as anti-trypanosomal agents.

A series of lysine-based vinyl sulfone peptidomimetics were synthesised and evaluated for anti-trypanosomal activity against bloodstream forms of T. brucei. This focused set of compounds, varying in the P3 position, were accessed in a divergent manner from a common intermediate (ammonium salt 8). Several P3 analogues exhibited sub-micromolar EC50 values, with thiourea 14, urea 15 and amide 21 representing the most potent anti-trypanosomal derivatives of the series. In order to establish an in vitro selectivity index the most active anti-trypanosomal compounds were also assessed for their impact on cell viability and cytotoxity effects in mammalian cells. Encouragingly, all compounds only reduced cellular metabolic activity in mammalian cells to a modest level and little, or no cytotoxicity, was observed with the series.

NF-κB inhibition prevents acute shear stress-induced inflammation in the saphenous vein graft endothelium.

The long saphenous vein (LSV) is commonly used as a conduit in coronary artery bypass grafting. However, long term patency remains limited by the development of vascular inflammation, intimal hyperplasia and accelerated atherosclerosis. The impact of acute exposure of venous endothelial cells (ECs) to acute arterial wall shear stress (WSS) in the arterial circulation, and the subsequent activation of inflammatory pathways, remain poorly defined. Here, we tested the hypothesis that acute exposure of venous ECs to high shear stress is associated with inflammatory responses that are regulated by NF-κB both in-vitro and ex-vivo. Analysis of the LSV endothelium revealed that activation of NF-κB occurred within 30 min after exposure to arterial rates of shear stress. Activation of NF-κB was associated with increased levels of CCL2 production and enhanced binding of monocytes in LSVECs exposed to 6 h acute arterial WSS. Consistent with this, ex vivo exposure of LSVs to acute arterial WSS promoted monocyte interactions with the vessel lumen. Inhibition of the NF-κB pathway prevented acute arterial WSS-induced CCL2 production and reduced monocyte adhesion, both in vitro and in human LSV ex vivo, demonstrating that this pathway is necessary for the induction of the acute arterial WSS-induced pro-inflammatory response. We have identified NF-κB as a critical regulator of acute endothelial inflammation in saphenous vein in response to acute arterial WSS. Localised endothelial-specific inhibition of the NF-κB pathway may be beneficial to prevent vein graft inflammation and consequent failure.

TLR-mediated activation of Waldenström macroglobulinemia B cells reveals an uncoupling from plasma cell differentiation.

Waldenström macroglobulinemia (WM) is a rare malignancy in which clonal B cells infiltrate the bone marrow and give rise to a smaller compartment of neoplastic plasma cells that secrete monoclonal immunoglobulin M paraprotein. Recent studies into underlying mutations in WM have enabled a much greater insight into the pathogenesis of this lymphoma. However, there is considerably less characterization of the way in which WM B cells differentiate and how they respond to immune stimuli. In this study, we assess WM B-cell differentiation using an established in vitro model system. Using T-cell-dependent conditions, we obtained CD138+ plasma cells from WM samples with a frequency similar to experiments performed with B cells from normal donors. Unexpectedly, a proportion of the WM B cells failed to upregulate CD38, a surface marker that is normally associated with plasmablast transition and maintained as the cells proceed with differentiation. In normal B cells, concomitant Toll-like receptor 7 (TLR7) activation and B-cell receptor cross-linking drives proliferation, followed by differentiation at similar efficiency to CD40-mediated stimulation. In contrast, we found that, upon stimulation with TLR7 agonist R848, WM B cells failed to execute the appropriate changes in transcriptional regulators, identifying an uncoupling of TLR signaling from the plasma cell differentiation program. Provision of CD40L was sufficient to overcome this defect. Thus, the limited clonotypic WM plasma cell differentiation observed in vivo may result from a strict requirement for integrated activation.

Toll-like receptor 9 and the inflammatory response to surgical trauma and cardiopulmonary bypass.

OBJECTIVES: Cardiac surgery can lead to post-operative end-organ complications secondary to activation of systemic inflammatory response. We hypothesize that surgical trauma or cardiopulmonary bypass (CPB) may initiate systemic inflammatory response via release of mitochondrial DNA (mtDNA) signaling Toll-like receptor 9 (TLR9) and interleukin-6 production (IL-6). MATERIALS AND METHODS: The role of TLR9 in systemic inflammatory response in cardiac surgery was studied using a murine model of sternotomy and a porcine model of sternotomy and CPB. mtDNA and IL-6 were measured with and without TLR9-antagonist treatment. To study ischemia-reperfusion injury, we utilized an ex-vivo porcine kidney model. RESULTS: In the rodent model (n = 15), circulating mtDNA increased 19-fold (19.29 ± 3.31, p < 0.001) and plasma IL-6 levels increased 59-fold (59.06 ± 14.98) at 1-min post-sternotomy compared to pre-sternotomy. In the murine model (n = 11), administration of TLR-9 antagonists lowered IL-6 expression post-sternotomy when compared to controls (59.06 ± 14.98 vs. 5.25 ± 1.08) indicating that TLR-9 is a positive regulator of IL-6 after sternotomy. Using porcine models (n = 10), a significant increase in circulating mtDNA was observed after CPB (Fold change 29.9 ± 4.8, p = 0.005) and along with IL-6 following renal ischaemia-reperfusion. Addition of the antioxidant sulforaphane reduced circulating mtDNA when compared to controls (FC 7.36 ± 0.61 vs. 32.0 ± 4.17 at 60 min post-CPB). CONCLUSION: CPB, surgical trauma and ischemic perfusion injury trigger the release of circulating mtDNA that activates TLR-9, in turn stimulating a release of IL-6. Therefore, TLR-9 antagonists may attenuate this response and may provide a future therapeutic target whereby the systemic inflammatory response to cardiac surgery may be manipulated to improve clinical outcomes.

A Simple Zinc-Mediated Method for Selenium Addition to Michael Acceptors.

In this work, we focused our attention on seleno-Michael type reactions. These were performed using zinc-selenolates generated in situ from diphenyl diselenide 1, 1,2-bis(3-phenylpropyl)diselenide 30, and protected selenocystine 31 via an efficient biphasic Zn/HCl-based reducing system. Alkenes with a variety of electron-withdrawing groups were investigated in order to gauge the scope and limitations of the process. Results demonstrated that the addition to acyclic α,ß-unsaturated ketones, aldehydes, esters amides, and acids was effectively achieved and that alkyl substituents at the reactive ß-centre can be accommodated. Similarly, cyclic enones undergo efficient Se-addition and the corresponding adducts were isolated in moderate to good yield. Vinyl sulfones, α,ß-unsaturated nitriles, and chalcones are not compatible with these reaction conditions. A recycling experiment demonstrated that the unreacted Zn/HCl reducing system can be effectively reused for seven reaction cycles (91% conversion yield at the 7° recycling rounds).

Pituitary hyperplasia with Sertoli cell-only and 47,XYY syndromes: an uncommon triad.

We report the case history of a 32-year-old man with no phenotypical abnormalities who presented with infertility. Semen analysis revealed azoospermia and testicular biopsy confirmed Sertoli cell-only (SCO) syndrome. Karyotyping revealed 47,XYY and pituitary hyperplasia was found on MRI pituitary. In our patient, 47,XYY karyotype is likely to have given rise to SCO syndrome that in turn resulted in pituitary hyperplasia. The patient was evaluated by various members of the multidisciplinary team including the pituitary surgeon, endocrinologist and andrologist. The patient's partner successfully delivered a healthy baby via in vitro fertilisation with donor sperm. This triad of diagnoses (SCO syndrome, 47,XYY karyotype and pituitary hyperplasia) has not been reported previously. SCO syndrome should be considered in the presence of azoospermia, elevated follicle-stimulating hormone, low inhibin-B and normal testosterone levels. Our case report also highlights the importance of excluding genetic causes of infertility even when the patient has no phenotypical abnormalities.

Neutrophil microvesicles drive atherosclerosis by delivering miR-155 to atheroprone endothelium.

Neutrophils are implicated in the pathogenesis of atherosclerosis but are seldom detected in atherosclerotic plaques. We investigated whether neutrophil-derived microvesicles may influence arterial pathophysiology. Here we report that levels of circulating neutrophil microvesicles are enhanced by exposure to a high fat diet, a known risk factor for atherosclerosis. Neutrophil microvesicles accumulate at disease-prone regions of arteries exposed to disturbed flow patterns, and promote vascular inflammation and atherosclerosis in a murine model. Using cultured endothelial cells exposed to disturbed flow, we demonstrate that neutrophil microvesicles promote inflammatory gene expression by delivering miR-155, enhancing NF-κB activation. Similarly, neutrophil microvesicles increase miR-155 and enhance NF-κB at disease-prone sites of disturbed flow in vivo. Enhancement of atherosclerotic plaque formation and increase in macrophage content by neutrophil microvesicles is dependent on miR-155. We conclude that neutrophils contribute to vascular inflammation and atherogenesis through delivery of microvesicles carrying miR-155 to disease-prone regions.