Young massive clusters (YMCs) with stellar masses of 10 4 -10 5 M and core stellar densities of 10 4 -10 5 stars per cubic pc are thought to be the "missing link" between open clusters and extreme extragalactic super star clusters and globular clusters. As such, studying the initial conditions of YMCs offers an opportunity to test cluster formation models across the full cluster mass range. G0.253 + 0.016 is an excellent candidate YMC progenitor. We make use of existing multi-wavelength data including recently available far-IR continuum (Herschel/Herschel Infrared Galactic Plane Survey) and mm spectral line (H 2 O Southern Galactic Plane Survey and Millimetre Astronomy Legacy Team 90 GHz Survey) data and present new, deep, multiple-filter, near-IR (Very Large Telescope/NACO) observations to study G0.253 + 0.016. These data show that G0.253 + 0.016 is a high-mass (1.3 × 10 5 M ), low-temperature (T dust ∼ 20 K), high-volume, and column density (n ∼ 8 × 10 4 cm −3 ; N H 2 ∼ 4 × 10 23 cm −2 ) molecular clump which is close to virial equilibrium (M dust ∼ M virial ) so is likely to be gravitationally bound. It is almost devoid of star formation and, thus, has exactly the properties expected for the initial conditions of a clump that may form an Arches-like massive cluster. We compare the properties of G0.253 + 0.016 to typical Galactic cluster-forming molecular clumps and find it is extreme, and possibly unique in the Galaxy. This uniqueness makes detailed studies of G0.253 + 0.016 extremely important for testing massive cluster formation models.
MicroRNAs (miRNAs) are small, non-coding RNA molecules that regulate gene expression post-transcriptionally. As a consequence of their function towards mRNA, miRNAs are widely associated with the pathogenesis of several human diseases, making miRNAs a target for new therapeutic strategies based on the control of their expression. Indeed, numerous works were published in the past decades showing the potential use of antisense oligonucleotides to target aberrant miRNAs (AMOs) involved in several human pathologies. New classes of chemical-modified-AMOs, including locked nucleic acid oligonucleotides, have recently proved their worth in silencing miRNAs. A correct design of a specific AMOs can help to improve their performance and potency towards the target miRNA by increasing for instance nuclease resistance and target affinity. This review outlines the technologies involved to suppress aberrant miRNAs. From the design strategies used in AMOs to its application in novel miRNA-based therapeutics and detection methodologies.
Context. A large sample of T Tauri stars exhibits optical jets, approximately half of which rotate slowly, only at ten per cent of their breakup velocity. The disk-locking mechanism has been shown to be inefficient to explain this observational fact. Aims. We show that low mass accreting T Tauri stars may have a strong stellar jet component that can effectively brake the star to the observed rotation speed. Methods. By means of a nonlinear separation of the variables in the full set of the MHD equations we construct semi-analytical solutions describing the dynamics and topology of the stellar component of the jet that emerges from the corona of the star. Results. We analyze two typical solutions with the same mass loss rate but different magnetic lever arms and jet radii. The first solution with a long lever arm and a wide jet radius effectively brakes the star and can be applied to the visible jets of T Tauri stars such as RY Tau. The second solution with a shorter lever arm and a very narrow jet radius may explain why similar stars, either weak line T Tauri stars (WTTS) or classical T Tauri stars (CTTS) do not all have visible jets. For instance, RY Tau itself seems to have different phases that probably depend on the activity of the star. Conclusions. First, stellar jets seem to be able to brake pre-main sequence stars with a low mass accreting rate. Second, jets may be visible only part time owing to changes in their boundary conditions. We also suggest a possible scenario for explaining the dichotomy between CTTS and WTTS, which rotate faster and do not have visible jets.
Background. Few data have been published regarding long-term mortality in patients with Parkinson's disease treated with DBS. Methods. This study analyzed long-term mortality rates, causes, and correlates in PD patients treated with DBS. Results. 184 consecutive patients were included; mean follow-up was 50 months. Fifteen deaths occurred (total 8.15%, annual mortality rate 1.94%). Mean age at disease onset and at surgery was 48 ± 2.4 and 63 ± 1.6 years, respectively. Mean disease duration until death was 21 ± 7.8 years. Most deaths related to stroke, myocardial infarction, other vascular/heart disorders, or severe infection; one suicide was recorded. Deceased PD patients were mostly male and had lower motor benefit after DBS, but univariate analysis failed to show significant differences regarding gender and motor benefit. Survival was 99% and 94% at 3 and 5 years. Conclusions. Long-term survival is to be expected in PD patients treated with DBS, possibly higher than previously expected. Death usually supervenes due to vascular events or infection.
The deposition of calcium phosphate on chemically polished commercially pure titanium immersed in Hank's balanced salt solution (HBSS) with bovine serum albumin (BSA) (concentrations 0 and 4 mg/mL) has been investigated. Electrochemical techniques, 125I labeling of albumin, scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy were used. A tricalcium phosphate layer with a thickness of ca. 1 microm was formed for periods of immersion in HBSS ranging between 1 and 2 weeks. A concentration of 4 mg/mL of BSA prevented its formation, even for periods as long as 1 month. In the absence of BSA, the electrochemical behavior of titanium specimens was significantly affected by the length of immersion time, reflecting the changes that slowly occur on their surface. In the presence of BSA, the surfaces maintained most of their original electrochemical activity. Surface studies have shown that calcium and phosphate become incorporated in the surface at very early stages of immersion. Albumin, which was rapidly adsorbed on titanium, was slowly desorbed when titanium was placed in HBSS. Protein and phosphate may coexist on the same surface, but initially adsorbed albumin molecules prevent the precipitation of a thick layer of tricalcium phosphate.
Despite rapid advances in cardiovascular research and therapeutic strategies, ischemic heart disease (IHD) remains the leading cause of mortality worldwide. MicroRNAs (miRNAs) are small, noncoding RNAs which post transcriptionally regulate gene expression. In the past few years, miRNAs have emerged as key tools for the understanding of the pathophysiology of IHD, with potential uses as new biomarkers and therapeutic targets. Several studies report a regulatory role of miRNAs, with regard to fundamental components of IHD pathogenesis and progression, such as lipoprotein metabolism, atherogenesis, vascular calcification, platelet function, and angiogenesis. Due to their high stability in biofluids, circulating miRNAs have attracted attention as promising biomarkers of IHD, especially in cardiovascular risk prediction and the diagnosis of myocardial infarction. Furthermore, experimental studies have demonstrated the potential of miRNA-targeted therapy in improving hyperlipidemia, atherosclerosis, and angiogenesis. In this review, the current knowledge on the role of miRNAs in IHD and translational perspectives of their use is discussed.
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