64 research outputs found

    Phylogenomics of Reichenowia parasitica, an Alphaproteobacterial Endosymbiont of the Freshwater Leech Placobdella parasitica

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    Although several commensal alphaproteobacteria form close relationships with plant hosts where they aid in (e.g.,) nitrogen fixation and nodulation, only a few inhabit animal hosts. Among these, Reichenowia picta, R. ornata and R. parasitica, are currently the only known mutualistic, alphaproteobacterial endosymbionts to inhabit leeches. These bacteria are harbored in the epithelial cells of the mycetomal structures of their freshwater leech hosts, Placobdella spp., and these structures have no other obvious function than housing bacterial symbionts. However, the function of the bacterial symbionts has remained unclear. Here, we focused both on exploring the genomic makeup of R. parasitica and on performing a robust phylogenetic analysis, based on more data than previous hypotheses, to test its position among related bacteria. We sequenced a combined pool of host and symbiont DNA from 36 pairs of mycetomes and performed an in silico separation of the different DNA pools through subtractive scaffolding. The bacterial contigs were compared to 50 annotated bacterial genomes and the genome of the freshwater leech Helobdella robusta using a BLASTn protocol. Further, amino acid sequences inferred from the contigs were used as queries against the 50 bacterial genomes to establish orthology. A total of 358 orthologous genes were used for the phylogenetic analyses. In part, results suggest that R. parasitica possesses genes coding for proteins related to nitrogen fixation, iron/vitamin B translocation and plasmid survival. Our results also indicate that R. parasitica interacts with its host in part by transmembrane signaling and that several of its genes show orthology across Rhizobiaceae. The phylogenetic analyses support the nesting of R. parasitica within the Rhizobiaceae, as sister to a group containing Agrobacterium and Rhizobium species

    Interleukin-6 receptor blockade in treatment-refractory MOG-IgG–associated disease and neuromyelitis optica spectrum disorders

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    BACKGROUND AND OBJECTIVES: To evaluate the long-term safety and efficacy of tocilizumab (TCZ), a humanized anti–interleukin-6 receptor antibody in myelin oligodendrocyte glycoprotein–IgG–associated disease (MOGAD) and neuromyelitis optica spectrum disorders (NMOSD). METHODS: Annualized relapse rate (ARR), Expanded Disability Status Scale score, MRI, autoantibody titers, pain, and adverse events were retrospectively evaluated in 57 patients with MOGAD (n = 14), aquaporin-4 (AQP4)-IgG seropositive (n = 36), and seronegative NMOSD (n = 7; 12%), switched to TCZ from previous immunotherapies, particularly rituximab. RESULTS: Patients received TCZ for 23.8 months (median; interquartile range 13.0–51.1 months), with an IV dose of 8.0 mg/kg (median; range 6–12 mg/kg) every 31.6 days (mean; range 26–44 days). For MOGAD, the median ARR decreased from 1.75 (range 0.5–5) to 0 (range 0–0.9; p = 0.0011) under TCZ. A similar effect was seen for AQP4-IgG+ (ARR reduction from 1.5 [range 0–5] to 0 [range 0–4.2]; p < 0.001) and for seronegative NMOSD (from 3.0 [range 1.0–3.0] to 0.2 [range 0–2.0]; p = 0.031). During TCZ, 60% of all patients were relapse free (79% for MOGAD, 56% for AQP4-IgG+, and 43% for seronegative NMOSD). Disability follow-up indicated stabilization. MRI inflammatory activity decreased in MOGAD (p = 0.04; for the brain) and in AQP4-IgG+ NMOSD (p < 0.001; for the spinal cord). Chronic pain was unchanged. Regarding only patients treated with TCZ for at least 12 months (n = 44), ARR reductions were confirmed, including the subgroups of MOGAD (n = 11) and AQP4-IgG+ patients (n = 28). Similarly, in the group of patients treated with TCZ for at least 12 months, 59% of them were relapse free, with 73% for MOGAD, 57% for AQP4-IgG+, and 40% for patients with seronegative NMOSD. No severe or unexpected safety signals were observed. Add-on therapy showed no advantage compared with TCZ monotherapy. DISCUSSION: This study provides Class III evidence that long-term TCZ therapy is safe and reduces relapse probability in MOGAD and AQP4-IgG+ NMOSD

    Interleukin-6 receptor blockade in treatment-refractory MOG-IgG-associated disease and neuromyelitis optica spectrum disorders

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    BACKGROUND AND OBJECTIVES: To evaluate the long-term safety and efficacy of tocilizumab (TCZ), a humanized anti-interleukin-6 receptor antibody in myelin oligodendrocyte glycoprotein-IgG-associated disease (MOGAD) and neuromyelitis optica spectrum disorders (NMOSD). METHODS: Annualized relapse rate (ARR), Expanded Disability Status Scale score, MRI, autoantibody titers, pain, and adverse events were retrospectively evaluated in 57 patients with MOGAD (n = 14), aquaporin-4 (AQP4)-IgG seropositive (n = 36), and seronegative NMOSD (n = 7; 12%), switched to TCZ from previous immunotherapies, particularly rituximab. RESULTS: Patients received TCZ for 23.8 months (median; interquartile range 13.0-51.1 months), with an IV dose of 8.0 mg/kg (median; range 6-12 mg/kg) every 31.6 days (mean; range 26-44 days). For MOGAD, the median ARR decreased from 1.75 (range 0.5-5) to 0 (range 0-0.9; p = 0.0011) under TCZ. A similar effect was seen for AQP4-IgG+ (ARR reduction from 1.5 [range 0-5] to 0 [range 0-4.2]; p < 0.001) and for seronegative NMOSD (from 3.0 [range 1.0-3.0] to 0.2 [range 0-2.0]; p = 0.031). During TCZ, 60% of all patients were relapse free (79% for MOGAD, 56% for AQP4-IgG+, and 43% for seronegative NMOSD). Disability follow-up indicated stabilization. MRI inflammatory activity decreased in MOGAD (p = 0.04; for the brain) and in AQP4-IgG+ NMOSD (p < 0.001; for the spinal cord). Chronic pain was unchanged. Regarding only patients treated with TCZ for at least 12 months (n = 44), ARR reductions were confirmed, including the subgroups of MOGAD (n = 11) and AQP4-IgG+ patients (n = 28). Similarly, in the group of patients treated with TCZ for at least 12 months, 59% of them were relapse free, with 73% for MOGAD, 57% for AQP4-IgG+, and 40% for patients with seronegative NMOSD. No severe or unexpected safety signals were observed. Add-on therapy showed no advantage compared with TCZ monotherapy. DISCUSSION: This study provides Class III evidence that long-term TCZ therapy is safe and reduces relapse probability in MOGAD and AQP4-IgG+ NMOSD

    Structure and TBP binding of the Mediator head subcomplex Med8–Med18–Med20.

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    The Mediator head module stimulates basal RNA polymerase II (Pol II) transcription and enables transcriptional regulation. Here we show that the head subunits Med8, Med18 and Med20 form a subcomplex (Med8/18/20) with two submodules. The highly conserved N-terminal domain of Med8 forms one submodule that binds the TATA box–binding protein (TBP) in vitro and is essential in vivo. The second submodule consists of the C-terminal region of Med8 (Med8C), Med18 and Med20. X-ray analysis of this submodule reveals that Med18 and Med20 form related beta-barrel folds. A conserved putative protein-interaction face on the Med8C/18/20 submodule includes sites altered by srb mutations, which counteract defects resulting from Pol II truncation. Our results and published data support a positive role of the Med8/18/20 subcomplex in initiation-complex formation and suggest that the Mediator head contains a multipartite TBP-binding site that can be modulated by transcriptional activators

    An international model to predict recurrent cardiovascular disease

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    Background: Prediction models for cardiovascular events and cardiovascular death in patients with established cardiovascular disease are not generally available. Methods: Participants from the prospective REduction of Atherothrombosis for Continued Health (REACH) Registry provided a global outpatient population with known cardiovascular disease at entry. Cardiovascular prediction models were estimated from the 2-year follow-up data of 49,689 participants from around the world. Results: A developmental prediction model was estimated from 33,419 randomly selected participants (2394 cardiovascular events with 1029 cardiovascular deaths) from the pool of 49,689. The number of vascular beds with clinical disease, diabetes, smoking, low body mass index, history of atrial fibrillation, cardiac failure, and history of cardiovascular event(s) <1 year before baseline examination increased risk of a subsequent cardiovascular event. Statin (hazard ratio 0.75; 95% confidence interval, 0.69-0.82) and acetylsalicylic acid therapy (hazard ratio 0.90; 95% confidence interval, 0.83-0.99) also were significantly associated with reduced risk of cardiovascular events. The prediction model was validated in the remaining 16,270 REACH subjects (1172 cardiovascular events, 494 cardiovascular deaths). Risk of cardiovascular death was similarly estimated with the same set of risk factors. Simple algorithms were developed for prediction of overall cardiovascular events and for cardiovascular death. Conclusions: This study establishes and validates a risk model to predict secondary cardiovascular events and cardiovascular death in outpatients with established atherothrombotic disease. Traditional risk factors, burden of disease, lack of treatment, and geographic location all are related to an increased risk of subsequent cardiovascular morbidity and cardiovascular mortality

    Prognosis of Atrial Fibrillation in Patients with Symptomatic Peripheral Arterial Disease: Data from the REduction of Atherothrombosis for Continued Health (REACH) Registry

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    BACKGROUND: Atrial fibrillation (AF) is a significant risk factor for cardiovascular (CV) mortality. This study aims to evaluate the prognostic implication of AF in patients with peripheral arterial disease (PAD). METHODS: The International Reduction of Atherothrombosis for Continued Health (REACH) Registry included 23,542 outpatients in Europe with established coronary artery disease, cerebrovascular disease (CVD), PAD and/or >/=3 risk factors. Of these, 3753 patients had symptomatic PAD. CV risk factors were determined at baseline. Study end point was a combination of cardiac death, non-fatal myocardial infarction (MI) and stroke (CV events) during 2 years of follow-up. Cox regression analysis adjusted for age, gender and other risk factors (i.e., congestive heart failure, coronary artery re-vascularisation, coronary artery bypass grafting (CABG), MI, hypertension, stroke, current smoking and diabetes) was used. RESULTS: Of 3753 PAD patients, 392 (10%) were known to have AF. Patients with AF were older and had a higher prevalence of CVD, diabetes and hypertension. Long-term CV mortality occurred in 5.6% of patients with AF and in 1.6% of those without AF (p<0.001). Multivariable analyses showed that AF was an independent predictor of late CV events (hazard ratio (HR): 1.5; 95% confidence interval (CI): 1.09-2.0). CONCLUSION: AF is common in European patients with symptomatic PAD and is independently associated with a worse 2-year CV outcome

    Telemedicine for acute stroke care: Review and recommendations from the German Competence Network Stroke

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    Telemedizinische Anwendungen mit klinischer Untersuchung des Patienten über Videokonferenz und Fernbefundung der zerebralen Schnittbildgebung haben verbreitete Nutzung in der akuten Schlaganfallversorgung insbesondere in Regionen mit unzureichenden neurologischen Behandlungseinrichtungen gefunden. Wissenschaftliche Untersuchungen haben die Zuverlässigkeit der neurologischen Fernuntersuchung bestätigt und die Indikation für die systemische Lysetherapie kann über Telekonsile mit entsprechenden technischen Qualitätsstandards sicher gestellt werden. Eine Verbesserung klinischer Behandlungsergebnisse konnte bisher aber nur gezeigt werden, wenn die Telemedizin in das Konzept der Stroke Unit mit spezialisierten Schlaganfalleinheiten und entsprechenden Qualitätsstandards eingebettet wurde. Außerhalb eines derartigen integrierten Konzeptes ist ein klinisches Benefit nicht nachgewiesen. Forschungsbedarf besteht im Bereich der Kosteneffizienz, des Qualitätsmanagements und der Implementierung weiterer technologischer Innovationen. Der Einsatz der Telemedizin in der Prävention, prähospitalen Schlaganfallversorgung, Rehabilitation und ambulanten Nachsorge ist nicht ausreichend untersucht und bedarf einer konsequenten wissenschaftlichen Evaluation
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