Neuropeptides regulate swimming depth of Platynereis larvae.

Cilia-based locomotion is the major form of locomotion for microscopic planktonic organisms in the ocean. Given their negative buoyancy, these organisms must control ciliary activity to maintain an appropriate depth. The neuronal bases of depth regulation in ciliary swimmers are unknown. To gain insights into depth regulation we studied ciliary locomotor control in the planktonic larva of the marine annelid, Platynereis. We found several neuropeptides expressed in distinct sensory neurons that innervate locomotor cilia. Neuropeptides altered ciliary beat frequency and the rate of calcium-evoked ciliary arrests. These changes influenced larval orientation, vertical swimming, and sinking, resulting in upward or downward shifts in the steady-state vertical distribution of larvae. Our findings indicate that Platynereis larvae have depth-regulating peptidergic neurons that directly translate sensory inputs into locomotor output on effector cilia. We propose that the simple circuitry found in these ciliated larvae represents an ancestral state in nervous system evolution.

Apixaban versus Aspirin for Embolic Stroke of Undetermined Source.

BACKGROUND: Rivaroxaban and dabigatran were not superior to aspirin in trials of patients with embolic stroke of undetermined source (ESUS). It is unknown whether apixaban is superior to aspirin in patients with ESUS and known risk factors for cardioembolism. METHODS: We conducted a multicenter, randomized, open-label, blinded-outcome trial of apixaban (5 mg twice daily) compared with aspirin (100 mg once daily) initiated within 28 days after ESUS in patients with at least one predictive factor for atrial fibrillation or a patent foramen ovale. Cardiac monitoring was mandatory, and aspirin treatment was switched to apixaban in case of atrial fibrillation detection. The primary outcome was any new ischemic lesion on brain magnetic resonance imaging (MRI) during 12-month follow-up. Secondary outcomes included major and clinically relevant nonmajor bleeding. RESULTS: A total of 352 patients were randomly assigned to receive apixaban (178 patients) or aspirin (174 patients) at a median of 8 days after ESUS. At 12-month follow-up, MRI follow-up was available in 325 participants (92.3%). New ischemic lesions occurred in 23 of 169 (13.6%) participants in the apixaban group and in 25 of 156 (16.0%) participants in the aspirin group (adjusted odds ratio, 0.79; 95% confidence interval, 0.42 to 1.48; P=0.57). Major and clinically relevant nonmajor bleeding occurred in five and seven participants, respectively (1-year cumulative incidences, 2.9 and 4.2; hazard ratio, 0.68; 95% confidence interval, 0.22 to 2.16). Serious adverse event rates were 43.9 per 100 person-years in those given apixaban and 45.7 per 100 person-years in those given aspirin. The Apixaban for the Treatment of Embolic Stroke of Undetermined Source trial was terminated after a prespecified interim analysis as a result of futility. CONCLUSIONS: Apixaban treatment was not superior to cardiac monitoring-guided aspirin in preventing new ischemic lesions in an enriched ESUS population. (Funded by Bristol-Myers Squibb and Medtronic Europe; ClinicalTrials.gov number, NCT02427126.)

De Novo Synthesis of Elastin by Exogenous Delivery of Synthetic Modified mRNA into Skin and Elastin-Deficient Cells.

Elastin is one of the most important and abundant extracellular matrix (ECM) proteins that provide elasticity and resilience to tissues and organs, including vascular walls, ligaments, skin, and lung. Besides hereditary diseases, such as Williams-Beuren syndrome (WBS), which results in reduced elastin synthesis, injuries, aging, or acquired diseases can lead to the degradation of existing elastin fibers. Thus, the de novo synthesis of elastin is required in several medical conditions to restore the elasticity of affected tissues. Here, we applied synthetic modified mRNA encoding tropoelastin (TE) for the de novo synthesis of elastin and determined the mRNA-mediated elastin synthesis in cells, as well as ex vivo in porcine skin. EA.hy926 cells, human fibroblasts, and mesenchymal stem cells (MSCs) isolated from a patient with WBS were transfected with 2.5 µg TE mRNA. After 24 hr, the production of elastin was analyzed by Fastin assay and dot blot analyses. Compared with untreated cells, significantly enhanced elastin amounts were detected in TE mRNA transfected cells. The delivered synthetic TE mRNA was even able to significantly increase the elastin production in elastin-deficient MSCs. In porcine skin, approximately 20% higher elastin amount was detected after the intradermal delivery of synthetic mRNA by microinjection. In this study, we demonstrated the successful applicability of synthetic TE encoding mRNA to produce elastin in elastin-deficient cells as well as in skin. Thus, this auspicious mRNA-based integration-free method has a huge potential in the field of regenerative medicine to induce de novo elastin synthesis, e.g., in skin, blood vessels, or alveoli.

Apixaban for treatment of embolic stroke of undetermined source (ATTICUS randomized trial): Rationale and study design.

Rationale Optimal secondary prevention of embolic stroke of undetermined source is not established. The current standard in these patients is acetylsalicylic acid, despite high prevalence of yet undetected paroxysmal atrial fibrillation. Aim The ATTICUS randomized trial is designed to determine whether the factor Xa inhibitor apixaban administered within 7 days after embolic stroke of undetermined source, is superior to acetylsalicylic acid for prevention of new ischemic lesions documented by brain magnetic resonance imaging within 12 months after index stroke. Design Prospective, randomized, blinded, parallel-group, open-label, German multicenter phase III trial in approximately 500 patients with embolic stroke of undetermined source. A key inclusion criterion is the presence or the planned implantation of an insertable cardiac monitor. Patients are 1:1 randomized to apixaban or acetylsalicylic acid and treated for a 12-month period. It is an event-driven trial aiming for core-lab adjudicated primary outcome events. Study outcomes The primary outcome is the occurrence of at least one new ischemic lesion identified by axial T2-weighted FLAIR magnetic resonance imaging and/or axial DWI magnetic resonance imaging at 12 months when compared with the baseline magnetic resonance imaging. Key secondary outcomes are the combination of recurrent ischemic strokes, hemorrhagic strokes, systemic embolism; combination of MACE including recurrent stroke, myocardial infarction, and cardiovascular death and combination of major and clinically relevant non-major bleeding defined according to ISTH, and change of cognitive function and quality of life (EQ-5D, Stroke Impact Scale). Discussion Embolic stroke of undetermined source is caused by embolic disease and associated with a high risk of recurrent ischemic strokes and clinically silent cerebral ischemic lesions. ATTICUS will investigate the impact of atrial fibrillation detected by insertable cardiac monitor and the effects of early anticoagulation with apixaban compared with antiplatelet therapy with acetylsalicylic acid on the incidence of new ischemic lesion after embolic stroke of undetermined source.

Optimized conditions for successful transfection of human endothelial cells with in vitro synthesized and modified mRNA for induction of protein expression.

BACKGROUND: The induction of protein synthesis by exogenous delivery of coding synthetic mRNA in desired cells is an auspicious strategy in the fields of basic cell biology, regenerative medicine, treatment of diseases, and reprogramming of cells. Here, we produced modified messenger RNA (mRNA) with reduced immune activation potential and increased stability and performed transfection experiments with different cells, HEK293 cells, BJ fibroblasts, and endothelial cells (ECs). RESULTS: The mRNA induced protein expression in cells was analyzed after transfection with different mRNA amounts and transfection reagents using flow cytometry. Different cell types showed different degrees of eGFP expression. HEK293 cells exhibited the highest eGFP expression compared to the BJ fibroblasts and ECs. However, the mRNA induced eGFP expression was detected in all cell types until 3 days after transfection. Already, the use of 0.5 µg of the synthesized mRNA led to the significant expression of eGFP in ECs. From all analyzed ECs approximately 87% were eGFP positive, which showed a high transfection efficiency. CONCLUSIONS: The synthesis of stabilized mRNA and the high transfection efficiency will enable the mRNA engineering of ECs as well as other somatic cells. The delivery of synthetic exogenous mRNA into cells allows the transient expression of desired proteins, which would be normally not expressed by the cells.

In vitro synthesis of modified mRNA for induction of protein expression in human cells.

The exogenous delivery of coding synthetic messenger RNA (mRNA) for induction of protein synthesis in desired cells has enormous potential in the fields of regenerative medicine, basic cell biology, treatment of diseases, and reprogramming of cells. Here, we describe a step by step protocol for generation of modified mRNA with reduced immune activation potential and increased stability, quality control of produced mRNA, transfection of cells with mRNA and verification of the induced protein expression by flow cytometry. Up to 3 days after a single transfection with eGFP mRNA, the transfected HEK293 cells produce eGFP. In this video article, the synthesis of eGFP mRNA is described as an example. However, the procedure can be applied for production of other desired mRNA. Using the synthetic modified mRNA, cells can be induced to transiently express the desired proteins, which they normally would not express.

New basic approach to treat non-small cell lung cancer based on RNA-interference.

BACKGROUND: To date the therapy for non-small cell lung cancer (NSCLC) is associated with severe side effects, frustrating outcomes, and does not consider different tumor characteristics. The RNA-interference (RNAi) pathway represents a potential new approach to treat NSCLC. With small interfering ribonucleic acids (siRNAs), it is possible to reduce the expression of proliferation-dependent proteins in tumor cells, leading to their apoptosis. We propose that siRNAs could be adapted to the tumor type and may cause fewer side effects than current therapy. METHODS: Four NSCLC cell lines were cultured under standard conditions and transfected with three different concentrations of siRNAs targeted against the hypoxia-inducible factors 1α and 2α (HIF1α and HIF2α) and signal transducer and activator of transcription 3 (STAT3). The expression was observed by quantitative real-time polymerase chain reaction and western blots. For the analysis of cell growth three days after transfection, the cell number was detected using a CASY cell counter system. RESULTS: The results of the silencing of the analyzed factors differ in each cell line. Cell growth was significantly reduced in all cell lines after transfection with HIF1α- and STAT3-siRNA. The silencing of HIF2α resulted in a significant effect on cell growth in squamous, and large-cell lung cancer. CONCLUSIONS: This study shows that the knockdown and viability to siRNA transfection differ in each tumor type according to the used siRNA. This implies that the tumor types differ among themselves and should be treated differently. Therefore, the authors suggest a possible approach to a more personalized treatment of NSCLC.