Searched for: school:SOM
Department/Unit:Cell Biology
Endothelin-1 supports clonal derivation and expansion of cardiovascular progenitors derived from human embryonic stem cells
Soh, Boon-Seng; Ng, Shi-Yan; Wu, Hao; Buac, Kristina; Park, Joo-Hye C; Lian, Xiaojun; Xu, Jiejia; Foo, Kylie S; Felldin, Ulrika; He, Xiaobing; Nichane, Massimo; Yang, Henry; Bu, Lei; Li, Ronald A; Lim, Bing; Chien, Kenneth R
Coronary arteriogenesis is a central step in cardiogenesis, requiring coordinated generation and integration of endothelial cell and vascular smooth muscle cells. At present, it is unclear whether the cell fate programme of cardiac progenitors to generate complex muscular or vascular structures is entirely cell autonomous. Here we demonstrate the intrinsic ability of vascular progenitors to develop and self-organize into cardiac tissues by clonally isolating and expanding second heart field cardiovascular progenitors using WNT3A and endothelin-1 (EDN1) human recombinant proteins. Progenitor clones undergo long-term expansion and differentiate primarily into endothelial and smooth muscle cell lineages in vitro, and contribute extensively to coronary-like vessels in vivo, forming a functional human-mouse chimeric circulatory system. Our study identifies EDN1 as a key factor towards the generation and clonal derivation of ISL1(+) vascular intermediates, and demonstrates the intrinsic cell-autonomous nature of these progenitors to differentiate and self-organize into functional vasculatures in vivo.
PMCID:4786749
PMID: 26952167
ISSN: 2041-1723
CID: 2046552
Up in Arms: Early primate proximal ulnae show affinities with non-quadrupedal, non-primate mammalian taxa [Meeting Abstract]
Ramirez, Kristen R.
ISI:000371255202112
ISSN: 0002-9483
CID: 3159382
A Randomized Clinical Trial of Single-Dose Versus Weekly Dalbavancin for Treatment of Acute Bacterial Skin and Skin Structure Infection
Dunne, Michael W; Puttagunta, Sailaja; Giordano, Philip; Krievins, Dainis; Zelasky, Michael; Baldassarre, James
BACKGROUND: Acute bacterial skin and skin structure infections (ABSSSIs) are a cause of significant morbidity and therapy can be a burden to the healthcare system. New antibiotics that simplify treatment and avoid hospitalization are needed. This study compared the safety and efficacy of a single intravenous infusion of 1500 mg of dalbavancin to the 2-dose regimen. METHODS: This study was a randomized, double-blind trial in patients aged >18 years with ABSSSIs. Patients were randomized to dalbavancin 1500 mg either as a single intravenous (IV) infusion or 1000 mg IV on day 1 followed 1 week later by 500 mg IV. The primary endpoint was a >/=20% reduction in the area of erythema at 48-72 hours in the intent-to-treat population. Noninferiority was to be declared if the lower limit of the 95% confidence interval (CI) on the difference in the outcomes was greater than -10%. Clinical outcome was also assessed at days 14 and 28. RESULTS: Six hundred ninety-eight patients were randomized. Demographic characteristics were similar on each regimen, although there were more patients with methicillin-resistant Staphylococcus aureus (MRSA) at baseline on the 2-dose regimen (36/210 [17.1%] vs 61/220 [27.7%]). Dalbavancin delivered as a single dose was noninferior to a 2-dose regimen (81.4% vs 84.2%; difference, -2.9% [95% CI, -8.5% to 2.8%]). Clinical outcomes were also similar at day 14 (84.0% vs 84.8%), day 28 (84.5% vs 85.1%), and day 14 in clinically evaluable patients with MRSA in a baseline culture (92.9% vs 95.3%) in the single- and 2-dose regimens, respectively. Treatment-emergent adverse events occurred in 20.1% of the single-dose patients and 19.9% on the 2-dose regimen. CONCLUSIONS: A single 1500-mg infusion of dalbavancin is noninferior to a 2-dose regimen, has a similar safety profile, and removes logistical constraints related to delivery of the second dose. CLINICAL TRIALS REGISTRATION: NCT02127970.
PMCID:4741365
PMID: 26611777
ISSN: 1537-6591
CID: 2216472
Threats from inside: Dynamic utility (Mis)alignments in an agent based model
Casey, William; Morales, Jose Andre; Mishra, Bud
We envision a game theoretic model of an organization so as to devise new mechanisms to improve compliance and reduce various insider threats - be it intentional or unintentional, while paying proportional attention to various intertwined issues: namely in the form of deception, privacy, trust, global utilities and stability. For this purpose, we primarily rely on a realistic formulation of classical information-asymmetric signaling games, in a repeated form, while allowing the agents to dynamically vary their strategic choices as their utilities get (mis)aligned. To better understand the multifaceted security concerns in existing and emerging multi-agent interactions within an organization, we map, model and analyze various challenging scenarios of threats: namely, those by design or those by negligence. We also describe a bridge to the future by investigating the extendability of the proposed mechanisms in a specific embodiment, where available meta-data is mined to model behavioral propensities of the agents. Simulation and empirical analysis indicate promising results for this approach to deliver new mechanisms and control regimes.
SCOPUS:84962418517
ISSN: 2093-5374
CID: 2852452
High-Speed Atomic Force Microscopy Revealing Contamination in DNA Purification Systems [Letter]
Mikheikin, Andrey; Olsen, Anita; Picco, Loren; Payton, Oliver; Mishra, Bud; Gimzewski, James K; Reed, Jason
Motivated by reports of low-level DNA contamination in popular commercial DNA purification kits, we employed a novel high-speed atomic force microscopy (HS-AFM) method to detect and characterize particulate and polymeric contaminants in four such systems: Qiagen MinElute PCR Purification, Zymo Research DNA Clean and Concentrator-5, Invitrogen ChargeSwitch-Pro PCR Purification, and Beckman Coulter AMPure XP. HS-AFM avoids amplification artifacts present in PCR or in the sequencing of amplified products, and it requires no chemical labels and easily achieves near-single-molecule sensitivity. Using this technique, we found trace levels of filamentous contamination, similar in appearance to dsDNA, in eluates from the Zymo, Qiagen, and ChargeSwitch kits. Conversely, we detected no contaminants in magnetic bead-based AMPure XP solutions. Eluates from the Zymo kits also tested positive for DNA in fluorescent intercalator dye and whole genome amplification (WGA) assays. Qiagen kits tested positive in the fluorescence assay but negative in the WGA assay. Both ChargeSwitch and AMPure XP tested negative in the fluorescence assay while the WGA results for these two kits were ambiguous. Taken together, our findings suggest AMPure XP would be the best choice for analyses requiring very high analytical stringency. While HS-AFM alone does not provide chemical specificity, it is a potentially valuable tool for characterizing and quantifying trace contaminants in molecular biology reagents and instruments in cases where conventional techniques fail.
PMID: 26878668
ISSN: 1520-6882
CID: 3122022
Multifocus microscopy with precise color multi-phase diffractive optics applied in functional neuronal imaging
Abrahamsson, Sara; Ilic, Rob; Wisniewski, Jan; Mehl, Brian; Yu, Liya; Chen, Lei; Davanco, Marcelo; Oudjedi, Laura; Fiche, Jean-Bernard; Hajj, Bassam; Jin, Xin; Pulupa, Joan; Cho, Christine; Mir, Mustafa; El Beheiry, Mohamed; Darzacq, Xavier; Nollmann, Marcelo; Dahan, Maxime; Wu, Carl; Lionnet, Timothee; Liddle, J Alexander; Bargmann, Cornelia I
Multifocus microscopy (MFM) allows high-resolution instantaneous three-dimensional (3D) imaging and has been applied to study biological specimens ranging from single molecules inside cells nuclei to entire embryos. We here describe pattern designs and nanofabrication methods for diffractive optics that optimize the light-efficiency of the central optical component of MFM: the diffractive multifocus grating (MFG). We also implement a "precise color" MFM layout with MFGs tailored to individual fluorophores in separate optical arms. The reported advancements enable faster and brighter volumetric time-lapse imaging of biological samples. In live microscopy applications, photon budget is a critical parameter and light-efficiency must be optimized to obtain the fastest possible frame rate while minimizing photodamage. We provide comprehensive descriptions and code for designing diffractive optical devices, and a detailed methods description for nanofabrication of devices. Theoretical efficiencies of reported designs is approximately 90% and we have obtained efficiencies of > 80% in MFGs of our own manufacture. We demonstrate the performance of a multi-phase MFG in 3D functional neuronal imaging in living C. elegans.
PMCID:4866461
PMID: 27231594
ISSN: 2156-7085
CID: 2385142
Reduced lung function in smokers in a lung cancer screening cohort with asbestos exposure and pleural plaques
Rom, William N; Lopatin, Sarah; Tsay, Jun-Chieh J; Addrizzo-Harris, Doreen; Munger, John S; Pass, Harvey
BACKGROUND: While low dose computed tomography (LDCT) screening for lung cancer is recommended for high-risk smokers, ages 55-74 years, information about asbestos exposure may not be routinely elicited. Asbestos exposure is associated with declining respiratory function over time; however, the effect of a history of asbestos exposure in LDCT screening cohorts is limited. We report the relationship between asbestos exposure and pulmonary function in a cohort of heavy smokers with a history of occupational asbestos exposure, hypothesizing that these subjects will have additional decreased pulmonary function. We also examined relationships between spirometric measurements and the presence of isolated pleural plaques. METHODS: A cross-sectional study was performed using data from the NYU Lung Cancer Biomarker Center cohort to compare study subjects with a history asbestos exposure primarily in the period since 1970 when tighter federal standards were in place (n = 359) to those without asbestos exposure (n = 1038) with respect to pulmonary function, LDCT lung imaging findings, and clinical symptoms. We further classified individuals with asbestos exposure by length of exposure time to examine the effect of duration of exposure on pulmonary function. Lastly, for asbestos-exposed participants, we examined the association of spirometric measurements with the presence of absence of isolated pleural plaques. RESULTS: Individuals with asbestos exposure had decreased FVC % predicted compared to those with no asbestos exposure (76% vs. 85% predicted, P < 0.01) and FEV1 % predicted (64% vs. 67% predicted, P < 0.01). Since there was no change in FEV1 /FVC ratio, the findings are consistent with restrictive impairment. Those with >/=20 years of exposure had a lower mean FVC % predicted compared to those with less than 20 years of exposure (74% vs. 78% predicted, P = 0.017). Individuals with asbestos exposure were more likely to have pleural plaques (P < 0.001) on CT. Those with isolated pleural plaques had lower mean % predicted FEV1 (P = 0.005) and FVC (P = 0.001) compared to those without pleural plaques. CONCLUSIONS: Occupational asbestos exposure in a cohort of heavy smokers was associated with a significant restrictive decline in pulmonary function, with longer duration of exposure associated with greater decline. The presence of isolated pleural plaques was also associated with reduced lung function. Am. J. Ind. Med. 9999:1-8, 2016. (c) 2016 Wiley Periodicals, Inc.
PMID: 26815630
ISSN: 1097-0274
CID: 1929652
CD8(+) T-cell Immune Evasion Enables Oncolytic Virus Immunotherapy
Pourchet, Aldo; Fuhrmann, Steven R; Pilones, Karsten A; Demaria, Sandra; Frey, Alan B; Mulvey, Matthew; Mohr, Ian
Although counteracting innate defenses allows oncolytic viruses (OVs) to better replicate and spread within tumors, CD8(+) T-cells restrict their capacity to trigger systemic anti-tumor immune responses. Herpes simplex virus-1 (HSV-1) evades CD8(+) T-cells by producing ICP47, which limits immune recognition of infected cells by inhibiting the transporter associated with antigen processing (TAP). Surprisingly, removing ICP47 was assumed to benefit OV immuno-therapy, but the impact of inhibiting TAP remains unknown because human HSV-1 ICP47 is not effective in rodents. Here, we engineer an HSV-1 OV to produce bovine herpesvirus UL49.5, which unlike ICP47, antagonizes rodent and human TAP. Significantly, UL49.5-expressing OVs showed superior efficacy treating bladder and breast cancer in murine models that was dependent upon CD8(+) T-cells. Besides injected subcutaneous tumors, UL49.5-OV reduced untreated, contralateral tumor size and metastases. These findings establish TAP inhibitor-armed OVs that evade CD8(+) T-cells as an immunotherapy strategy to elicit potent local and systemic anti-tumor responses.
PMCID:4816761
PMID: 27077112
ISSN: 2352-3964
CID: 2078152
The pituitary TGFbeta1 system as a novel target for the treatment of resistant prolactinomas
Recouvreux, Maria Victoria; Camilletti, Maria Andrea; Rifkin, Daniel B; Diaz-Torga, Graciela
Prolactinomas are the most frequently observed pituitary adenomas and most of them respond well to conventional treatment with dopamine agonists. However, a subset of prolactinomas fails to respond to such therapies and is considered as dopamine agonist-resistant prolactinomas (DARPs). New therapeutic approaches are necessary for these tumors. TGFbeta1 is a known inhibitor of lactotroph cell proliferation and prolactin secretion, and it partly mediates dopamine inhibitory action. TGFbeta1 is secreted to the extracellular matrix as an inactive latent complex, and its bioavailability is tightly regulated by different components of the TGFbeta1 system including latent binding proteins (LTBPs), local activators (Thrombospondin-1, matrix metalloproteases, integrins, among others), and TGFbeta receptors. Pituitary TGFbeta1 activity and the expression of different components of the TGFbeta1 system, are regulated by dopamine and estradiol. Prolactinomas (animal models and humans) present reduced TGFbeta1 activity as well as reduced expression of several components of the TGFbeta1 system. Therefore, restoration of TGFbeta1 inhibitory activity represents a novel therapeutic approach to bypass dopamine action in DARPs. The aim of this review is to summarize the large literature supporting TGFbeta1 important role as a local modulator of pituitary lactotroph function; as well to provide recent evidence of the restoration of TGFbeta1 activity as an effective treatment in experimental prolactinomas.
PMCID:4760866
PMID: 26698564
ISSN: 1479-6805
CID: 1884212
ARVC/D and the dyad: A long distance relationship? [Editorial]
Delmar, Mario
PMID: 26593332
ISSN: 1556-3871
CID: 1964452