Depletion of B-cells with rituximab improves endothelial function and reduces inflammation among individuals with rheumatoid arthritis.

BackgroundIndividuals with rheumatoid arthritis (RA) are at increased risk for cardiovascular disease, partly due to systemic inflammation and endothelial dysfunction. B-cells play an important pathogenic role in the inflammatory process that drives RA disease activity. Rituximab, a chimeric murine/human monoclonal antibody that depletes B-cells, is an effective therapy for RA. The purpose of this study was to determine whether B-cell depletion with rituximab reduces systemic inflammation and improves macrovascular (brachial artery flow-mediated dilation, FMD) and microvascular (reactive hyperemia) endothelial function in RA patients.Methods and resultsRA patients received a single course of rituximab (1000 mg IV infusion at baseline and on day 15). FMD, reactive hyperemia, inflammatory markers, and clinical assessments were performed at baseline, week 12, and week 24. Twenty patients (95% female, median age 54 years) completed the study. Following treatment, FMD improved from a baseline of 4.5±0.4% to 6.4±0.6% at 12 weeks (mean±SE; P<0.0001), followed by a decline at week 24; a similar pattern was observed for hyperemic velocity. Significant decreases in RA disease scores, high-sensitivity C-reactive protein, erythrocyte sedimentation rate, and circulating CD19+ B-cells were sustained through week 24. Cholesterol and triglycerides became significantly although modestly elevated during the study.ConclusionsDepletion of B-cells with rituximab improved macrovascular and microvascular endothelial function and reduced systemic inflammation, despite modest elevation in lipids. Given these results, rituximab should be evaluated in the future for its possible role in reducing excess cardiovascular risk in RA.Clinical trial registrationURL http://ClinicalTrials.gov. Unique identifier: NCT00844714

Carotid Intima-Media Thickness Progression in HIV-Infected Adults Occurs Preferentially at the Carotid Bifurcation and Is Predicted by Inflammation.

BackgroundShear stress gradients and inflammation have been causally associated with atherosclerosis development in carotid bifurcation regions. The mechanism underlying higher levels of carotid intima-media thickness observed among HIV-infected individuals remains unknown.Methods and resultsWe measured carotid intima-media thickness progression and development of plaque in the common carotid, bifurcation region, and internal carotid artery in 300 HIV-infected persons and 47 controls. The median duration of follow-up was 2.4 years. When all segments were included, the rate of intima-media thickness progression was greater in HIV-infected subjects compared with controls after adjustment for traditional risk factors (0.055 vs. 0.024 mm/year, P=0.016). Rate of progression was also greater in the bifurcation region (0.067 vs. 0.025 mm/year, P=0.042) whereas differences were smaller in the common and internal regions. HIV-infected individuals had a greater incidence of plaque compared with controls in the internal (23% vs. 6.4%, P=0.0037) and bifurcation regions (34% vs. 17%, P=0.014). Among HIV-infected individuals, the rate of progression in the bifurcation region was more rapid compared with the common carotid, internal, or mean intima-media thickness; in contrast, progression rates among controls were similar at all sites. Baseline hsCRP was elevated in HIV-infected persons and was a predictor of progression in the bifurcation region.ConclusionsAtherosclerosis progresses preferentially in the carotid bifurcation region in HIV-infected individuals. hsCRP, a marker of inflammation, is elevated in HIV and is associated with progression in the bifurcation region. These data are consistent with a model in which the interplay between hemodynamic shear stresses and HIV-associated inflammation contribute to accelerated atherosclerosis. (J Am Heart Assoc. 2012;1:jah3-e000422 doi: 10.1161/JAHA.111.000422.)Clinical trial registrationURL: http://clinicaltrials.gov. Unique identifier: NCT01519141

Angiogenesis is present in experimental autoimmune encephalomyelitis and pro-angiogenic factors are increased in multiple sclerosis lesions

<p>Abstract</p> <p>Background</p> <p>Angiogenesis is a common finding in chronic inflammatory diseases; however, its role in multiple sclerosis (MS) is unclear. Central nervous system lesions from both MS and experimental autoimmune encephalomyelitis (EAE), the animal model of MS, contain T cells, macrophages and activated glia, which can produce pro-angiogenic factors. Previous EAE studies have demonstrated an increase in blood vessels, but differences between the different phases of disease have not been reported. Therefore we examined angiogenic promoting factors in MS and EAE lesions to determine if there were changes in blood vessel density at different stages of EAE.</p> <p>Methods</p> <p>In this series of experiments we used a combination of vascular casting, VEGF ELISA and immunohistochemistry to examine angiogenesis in experimental autoimmune encephalomyelitis (EAE). Using immunohistochemistry we also examined chronic active MS lesions for angiogenic factors.</p> <p>Results</p> <p>Vascular casting and histological examination of the spinal cord and brain of rats with EAE demonstrated that the density of patent blood vessels increased in the lumbar spinal cord during the relapse phase of the disease (p < 0.05). We found an increased expression of VEGF by inflammatory cells and a decrease in the recently described angiogenesis inhibitor meteorin. Examination of chronic active human MS tissues demonstrated glial expression of VEGF and glial and blood vessel expression of the pro-angiogenic receptor VEGFR2. There was a decreased expression of VEGFR1 in the lesions compared to normal white matter.</p> <p>Conclusions</p> <p>These findings reveal that angiogenesis is intimately involved in the progression of EAE and may have a role in MS.</p

The missing conformer: A comprehensive rotational spectroscopy study and astronomical search of two conformers of methyl cyanoacetate

We performed a comprehensive investigation of methyl cyanoacetate (MCA) using high-resolution Fourier transform rotational spectroscopy. Two low energy conformers of MCA were observed in the vibrational ground state, in selected frequency regions from 2 to 110 GHz. We report accurately determined line lists, rotational constants, centrifugal distortion constants, and nuclear quadrupole coupling constants for both conformers, as well as for several singly substituted heavy-atom isotopologues. One of the conformers was previously reported; however, the rotational transitions of the second conformer, which is newly described here, are observed to be generally more intense than the latter. The accurate predictions of rotational transitions into the millimeter-wave region can facilitate the detection of these conformers of MCA in the interstellar medium. Using the rotational spectroscopy data provided here, we searched for the two conformers of MCA in a deep and unbiased spectral survey of the molecular cloud G+0.693- 0.027 located in the Galactic Center. None of the MCA conformers were detected. The upper limits for their abundances were derived with respect to the abundance of molecular hydrogen

Bypassing Iron Storage in Endodermal Vacuoles Rescues the Iron Mobilization Defect in the Natural Resistance Associated-Macrophage Protein3natural Resistance Associated-Macrophage Protein4 Double Mutant

To improve seed iron (Fe) content and bioavailability, it is crucial to decipher the mechanisms that control Fe storage during seed development. In Arabidopsis (Arabidopsis thaliana) seeds, most Fe is concentrated in insoluble precipitates, with phytate in the vacuoles of cells surrounding the vasculature of the embryo. NATURAL RESISTANCE ASSOCIATED-MACROPHAGE PROTEIN3 (AtNRAMP3) and AtNRAMP4 function redundantly in Fe retrieval from vacuoles during germination. When germinated under Fe-deficient conditions, development of the nramp3nramp4 double mutant is arrested as a consequence of impaired Fe mobilization. To identify novel genes involved in seed Fe homeostasis, we screened an ethyl methanesulfonate-mutagenized population of nramp3nramp4 seedlings for mutations suppressing their phenotypes on low Fe. Here, we report that, among the suppressors, two independent mutations in the VACUOLAR IRON TRANSPORTER1 (AtVIT1) gene caused the suppressor phenotype. The AtVIT1 transporter is involved in Fe influx into vacuoles of endodermal and bundle sheath cells. This result establishes a functional link between Fe loading in vacuoles by AtVIT1 and its remobilization by AtNRAMP3 and AtNRAMP4. Moreover, analysis of subcellular Fe localization indicates that simultaneous disruption of AtVIT1, AtNRAMP3, and AtNRAMP4 limits Fe accumulation in vacuolar globoids

Ezetimibe Alone Reduces Low‐Density Lipoprotein Cholesterol in HIV‐Infected Patients Receiving Combination Antiretroviral Therapy

In this crossover study of ezetimibe monotherapy in 48 antiretroviral-treated patients with human immunodeficiency virus infection, the mean changes in low-density lipoprotein cholesterol were -5.3% (-11 mg/dL) and + 5.5% (+ 4 mg/ dL) with ezetimibe treatment and placebo, respectively (P = .04). Ezetimibe was safe and effective in reducing low-density lipoprotein cholesterol and is an option for patients who cannot tolerate treatment with a statin

Structure-function study of maize ribosome-inactivating protein: implications for the internal inactivation region and the sole glutamate in the active site

Maize ribosome-inactivating protein is classified as a class III or an atypical RNA N-glycosidase. It is synthesized as an inactive precursor with a 25-amino acid internal inactivation region, which is removed in the active form. As the first structural example of this class of proteins, crystals of the precursor and the active form were diffracted to 2.4 and 2.5 Å, respectively. The two proteins are similar, with main chain root mean square deviation (RMSD) of 0.519. In the precursor, the inactivation region is found on the protein surface and consists of a flexible loop followed by a long α-helix. This region diminished both the interaction with ribosome and cytotoxicity, but not cellular uptake. Like bacterial ribosome-inactivating proteins, maize ribosome-inactivating protein does not have a back-up glutamate in the active site, which helps the protein to retain some activity if the catalytic glutamate is mutated. The structure reveals that the active site is too small to accommodate two glutamate residues. Our structure suggests that maize ribosome-inactivating protein may represent an intermediate product in the evolution of ribosome-inactivating proteins. © 2007 The Author(s).published_or_final_versio

Identification of a novel splice variant form of the influenza a virus m2 ion channel with an antigenically distinct ectodomain

Segment 7 of influenza A virus produces up to four mRNAs. Unspliced transcripts encode M1, spliced mRNA2 encodes the M2 ion channel, while protein products from spliced mRNAs 3 and 4 have not previously been identified. The M2 protein plays important roles in virus entry and assembly, and is a target for antiviral drugs and vaccination. Surprisingly, M2 is not essential for virus replication in a laboratory setting, although its loss attenuates the virus. To better understand how IAV might replicate without M2, we studied the reversion mechanism of an M2-null virus. Serial passage of a virus lacking the mRNA2 splice donor site identified a single nucleotide pseudoreverting mutation, which restored growth in cell culture and virulence in mice by upregulating mRNA4 synthesis rather than by reinstating mRNA2 production. We show that mRNA4 encodes a novel M2-related protein (designated M42) with an antigenically distinct ectodomain that can functionally replace M2 despite showing clear differences in intracellular localisation, being largely retained in the Golgi compartment. We also show that the expression of two distinct ion channel proteins is not unique to laboratory-adapted viruses but, most notably, was also a feature of the 1983 North American outbreak of H5N2 highly pathogenic avian influenza virus. In identifying a 14th influenza A polypeptide, our data reinforce the unexpectedly high coding capacity of the viral genome and have implications for virus evolution, as well as for understanding the role of M2 in the virus life cycle

Improved clinical investigation and evaluation of high-risk medical devices: the rationale and objectives of CORE-MD (Coordinating Research and Evidence for Medical Devices)

: In the European Union (EU) the delivery of health services is a national responsibility but there are concerted actions between member states to protect public health. Approval of pharmaceutical products is the responsibility of the European Medicines Agency, whereas authorizing the placing on the market of medical devices is decentralized to independent 'conformity assessment' organizations called notified bodies. The first legal basis for an EU system of evaluating medical devices and approving their market access was the medical device directives, from the 1990s. Uncertainties about clinical evidence requirements, among other reasons, led to the EU Medical Device Regulation (2017/745) that has applied since May 2021. It provides general principles for clinical investigations but few methodological details-which challenges responsible authorities to set appropriate balances between regulation and innovation, pre- and post-market studies, and clinical trials and real-world evidence. Scientific experts should advise on methods and standards for assessing and approving new high-risk devices, and safety, efficacy, and transparency of evidence should be paramount. The European Commission recently awarded a Horizon 2020 grant to a consortium led by the European Society of Cardiology and the European Federation of National Associations of Orthopaedics and Traumatology, that will review methodologies of clinical investigations, advise on study designs, and develop recommendations for aggregating clinical data from registries and other real-world sources. The CORE-MD project (Coordinating Research and Evidence for Medical Devices) will run until March 2024; here we describe how it may contribute to the development of regulatory science in Europe