Polarization signals in mantis shrimps

While color signals are well known as a form of animal communication, a number of animals communicate using signals based on patterns of polarized light reflected from specialized body parts or structures. Mantis shrimps, a group of marine crustaceans, have evolved a great diversity of such signals, several of which are based on photonic structures. These include resonant scattering devices, structures based on layered dichroic molecules, and structures that use birefringent layers to produce circular polarization. Such biological polarizers operate in different spectral regions ranging from the near-UV to medium wavelengths of visible light. In addition to the structures that are specialized for signal production, the eyes of many species of mantis shrimp are adapted to detect linearly polarized light in the ultraviolet and in the green, using specialized sets of photoreceptors with oriented, dichroic visual pigments. Finally, a few mantis shrimp species produce biophotonic retarders within their photoreceptors that permit the detection of circularly polarized light and are thus the only animals known to sense this form of polarization. Mantis shrimps use polarized light in species-specific signals related to mating and territorial defense, and their means of manipulating light's polarization can inspire designs for artificial polarizers and achromatic retarders

miR-25 targets TNF-related apoptosis inducing ligand (TRAIL) death receptor-4 and promotes apoptosis resistance in cholangiocarcinoma.

It has been established that microRNA expression and function contribute to phenotypic features of malignant cells, including resistance to apoptosis. Although targets and functional roles for a number of microRNAs have been described in cholangiocarcinoma, many additional microRNAs dysregulated in this tumor have not been assigned functional roles. In this study, we identify elevated miR-25 expression in malignant cholangiocarcinoma cell lines as well as patient samples. In cultured cells, treatment with the Smoothened inhibitor, cyclopamine, reduced miR-25 expression, suggesting Hedgehog signaling stimulates miR-25 production. Functionally, miR-25 was shown to protect cells against TNF-related apoptosis-inducing ligand (TRAIL)-induced apoptosis. Correspondingly, antagonism of miR-25 in culture sensitized cells to apoptotic death. Computational analysis identified the TRAIL Death Receptor-4 (DR4) as a potential novel miR-25 target, and this prediction was confirmed by immunoblot, cell staining, and reporter assays. CONCLUSION: These data implicate elevated miR-25 levels in the control of tumor cell apoptosis in cholangiocarcinoma. The identification of the novel miR-25 target DR4 provides a mechanism by which miR-25 contributes to evasion of TRAIL-induced cholangiocarcinoma apoptosis

Light Curves of Core-Collapse Supernovae with Substantial Mass Loss using the New Open-Source SuperNova Explosion Code (SNEC)

We present the SuperNova Explosion Code (SNEC), an open-source Lagrangian code for the hydrodynamics and equilibrium-diffusion radiation transport in the expanding envelopes of supernovae. Given a model of a progenitor star, an explosion energy, and an amount and distribution of radioactive nickel, SNEC generates the bolometric light curve, as well as the light curves in different wavelength bands assuming black body emission. As a first application of SNEC, we consider the explosions of a grid of 15 M_⊙ (at zero-age main sequence) stars whose hydrogen envelopes are stripped to different extents and at different points in their evolution. The resulting light curves exhibit plateaus with durations of ∼20 − 100 days if & 1.5 − 2 M_⊙ of hydrogen-rich material is left and no plateau if less hydrogen-rich material is left. The shorter plateau lengths are unlike the Type IIP supernova light curves typically observed in nature. This suggests that, at least for zero-age main sequence masses . 20 M_⊙, hydrogen mass loss occurs as an all or nothing process, perhaps pointing to the important role binary interactions play in observed mass-stripped supernovae (i.e., Type Ib/c events). These light curves are also unlike what is typically seen for Type IIL supernovae, arguing that simply varying the amount of mass loss cannot explain these events. The most stripped models begin to show double-peaked light curves similar to what is often seen for Type IIb supernovae, confirming previous work that these supernovae can come from progenitors that have a small amount of hydrogen and a radius of ∼ 500 R_⊙

Structural Activity Relationship Study on Dual PLK1 /BRD4 Inhibitor, BI- 2536

Polo-like kinase 1 (PLK1) and BRD4 are two different therapeutic targets in cancer drug discovery. Recently it has been reported that PLK1 inhibitor, BI-2536, is also a potent inhibitor of BRD4. The simultaneous inhibition of PLK1 and BRD4 by a single drug molecule is interesting because this could lead to the development of effective therapeutic strategy for different types of disease conditions in which PLK1 and BRD4 are implicated. Structural activity relationship studies has been carried out on BI-2536 to generate analogs with enhanced dual inhibitory activity against BRD4 and PLK1 as well as to render the molecule selective to one target over the other. UMB101 and 160 have been found to exhibit enhanced dual inhibitory activity with selectivity fold of less than 30, UMB160 being the most potent dual-kinase bromodomain inhibitor (BRD4 IC50 = 28 nM, PLK1 IC50 = 40 nM). UMB131 was found to be the most selective PLK1 inhibitor over BRD4

Spectral Typing of Late Type Stellar Companions to Young Stars from Low Dispersion Near-Infrared Integral Field Unit Data

We used the Project 1640 near-infrared coronagraph and integral field spectrograph to observe 19 young solar type stars. Five of these stars are known binary stars and we detected the late-type secondaries and were able to measure their JH spectra with a resolution of R\sim30. The reduced, extracted, and calibrated spectra were compared to template spectra from the IRTF spectral library. With this comparison we test the accuracy and consistency of spectral type determination with the low-resolution near-infrared spectra from P1640. Additionally, we determine effective temperature and surface gravity of the companions by fitting synthetic spectra calculated with the PHOENIX model atmosphere code. We also present several new epochs of astrometry of each of the systems. Together these data increase our knowledge and understanding of the stellar make up of these systems. In addition to the astronomical results, the analysis presented helps validate the Project 1640 data reduction and spectral extraction processes and the utility of low-resolution, near-infrared spectra for characterizing late-type companions in multiple systems.Comment: Accepted to Astronomical Journal, 25 pages, 8 figure

Commentary: Use of BACTRAC Proteomic Database-Uromodulin Protein Expression during Ischemic Stroke

Introduction: Uromodulin (UMOD) is a glycoprotein expressed by the epithelial cells of the thick ascending limb of Henle\u27s loop in the kidney. Research has shown that increased uromodulin expression may be associated with lower risk of cardiovascular disease in adults. Utilizing the Blood and Clot Thrombectomy Registry and Collaboration (BACTRAC) (clinicaltrials.gov NCT03153683), a continuously enrolling tissue bank, we aimed to examine the associations between serum uromodulin, age, and high BMI (BMI\u3e 25) and its relationship to stroke in patients. Methods: Arterial blood distal and proximal to the thrombus was collected during a thrombectomy procedure using the BACTRAC protocol and sent to Olink (Boston, MA) to determine proteomic expression via proximity extension assay. Uromodulin expression was recorded and analyzed using two tailed T-tests and linear regressions. Results: The relationship between systemic and intracranial uromodulin, age, high BMI and hypertension were assessed. Systemic and intracranial uromodulin decreased with age (p\u3c 0.0001 and r²= 0.343, p= 0.0416 and r²= 0.102) respectively. Systemic uromodulin expression increased with BMI\u3e 25 (p= 0.014). Presence of hypertension decreased uromodulin’s expression systemically (p= 0.018) and intracranially (p= 0.007). Conclusions: Uromodulin was increased significantly in overweight patients, decreased significantly in older patients, and decreased in patients with hypertension. The increase in uromodulin in people with high BMI could be a protective reaction of the kidney to worsening conditions that make ischemic stroke more likely, with a goal of delaying dangerous outcomes. The decreased expression of uromodulin in older adults could be associated with the decline of general kidney function that accompanies aging. Hypertension can contribute to an AKI by decreasing perfusion to the kidney, therefore decreasing kidney function and uromodulin production. Further analyses are needed to understand the role of uromodulin following ischemic stroke

Smoking-Induced Sex Differences in Clinical Outcomes in Patients Undergoing Mechanical Thrombectomy for Stroke

OBJECTIVE: Ischemic stroke is the fifth leading cause of death in the United States. Smoking accelerates the onset of stroke by 10 years. The effects of smoking status on percent change in National Institutes of Health Stroke Scale (NIHSS) score, infarct volume, and edema volume were examined following mechanical thrombectomy for large vessel occlusion in patients with acute ischemic stroke. METHODS: Subjects (N = 90; \u3e18 years old) were divided into 3 groups based on smoking status: current smokers, previous smokers (defined as having quit \u3e6 months before the ischemic event), and nonsmokers. Percent change in NIHSS score was defined as score at admission minus score at discharge divided by score at admission and was used as a predictor of functional outcome. Linear regression analysis was performed based on infarct or edema volume versus percent change in NIHSS score and separated by sex. RESULTS: Consistent with previous findings, smokers experienced a stroke 10 years earlier than nonsmokers (P = 0.004). Statistically significant linear regressions existed between infarct volume or edema volume in relation to worsening change in NIHSS score with female smokers only. Stroke-induced tissue damage, as measured by magnetic resonance imaging or computed tomography, was predictive of functional recovery only in female smokers. CONCLUSIONS: These findings are valuable for patient counseling, particularly for women, for smoking cessation