Cloning and Characterization of Subunits of the T-Cell Receptor and Murine Leukemia Virus Enhancer Core-Binding Factor.

Moloney murine leukemia virus causes thymic leukemias when injected into newborn mice. A major determinant of the thymic disease specificity of Moloney virus genetically maps to the conserved viral core motif in the Moloney virus enhancer. Point mutations introduced into the core site significantly shifted the disease specificity of the Moloney virus from thymic leukemia to erythroid leukemia (N.A. Speck, B. Renjifo, E. Golemis, T.N. Fredrickson, J.W. Hartley, and N. Hopkins, Genes Dev. 4:233-242, 1990). We previously reported the purification of core-binding factors (CBF) from calf thymus nuclei (S. Wang and N.A. Speck, Mol. Cell. Biol. 12:89-102, 1992). CBF binds to core sites in murine leukemia virus and T-cell receptor enhancers. Affinity-purified CBF contains multiple polypeptides. In this study, we sequenced five tryptic peptides from two of the bovine CBF proteins and isolated three cDNA clones from a mouse thymus cDNA library encoding three of the tryptic peptides from the bovine proteins. The cDNA clones, which we call CBF beta p22.0, CBF beta p21.5, and CBF beta p17.6, encode three highly related but distinct proteins with deduced molecular sizes of 22.0, 21.5, and 17.6 kDa that appear to be translated from multiply spliced mRNAs transcribed from the same gene. CBF beta p22.0, CBF beta p21.5, and CBF beta p17.6 do not by themselves bind the core site. However, CBF beta p22.0 and CBF beta p21.5 form a complex with DNA-binding CBF alpha subunits and as a result decrease the rate of dissociation of the CBF protein-DNA complex. Association of the CBF beta subunits does not extend the phosphate contacts in the binding site. We propose that CBF beta is a non-DNA-binding subunit of CBF and does not contact DNA directly

Spectral signatures of photosynthesis II: coevolution with other stars and the atmosphere on extrasolar worlds

As photosynthesis on Earth produces the primary signatures of life that can be detected astronomically at the global scale, a strong focus of the search for extrasolar life will be photosynthesis, particularly photosynthesis that has evolved with a different parent star. We take planetary atmospheric compositions simulated by Segura, et al. (2003, 2005) for Earth-like planets around observed F2V and K2V stars, modeled M1V and M5V stars, and around the active M4.5V star AD Leo; our scenarios use Earth's atmospheric composition as well as very low O2 content in case anoxygenic photosynthesis dominates. We calculate the incident spectral photon flux densities at the surface of the planet and under water. We identify bands of available photosynthetically relevant radiation and find that photosynthetic pigments on planets around F2V stars may peak in absorbance in the blue, K2V in the red-orange, and M stars in the NIR, in bands at 0.93-1.1 microns, 1.1-1.4 microns, 1.5-1.8 microns, and 1.8-2.5 microns. In addition, we calculate wavelength restrictions for underwater organisms and depths of water at which they would be protected from UV flares in the early life of M stars. We estimate the potential productivity for both surface and underwater photosynthesis, for both oxygenic and anoxygenic photosynthesis, and for hypothetical photosynthesis in which longer wavelength, multi-photosystem series are used.Comment: 59 pages, 4 figures, 4 tables, forthcoming in Astrobiology ~March 200

Clinicians’ Perceptions of The Health Status of Formerly Detained Immigrants

Background In the past decade, the U.S. immigration detention system regularly detained more than 30,000 people; in 2019 prior to the pandemic, the detention population exceeded 52,000 people. Inhumane detention conditions have been documented by internal government watchdogs, news media and human rights groups, finding over-crowding, poor hygiene and sanitation and poor and delayed medical care, as well as verbal, physical and sexual abuse. Methods This study surveyed health professionals across the United States who had provided care for immigrants who were recently released from immigration detention to assess clinician perceptions about the adverse health impact of immigration detention on migrant populations based on real-life clinical encounters. There were 150 survey responses, of which 85 clinicians observed medical conditions attributed to detention. Results These 85 clinicians reported seeing a combined 1300 patients with a medical issue related to their time in detention, including patients with delayed access to medical care or medicine in detention, patients with new or acute health conditions including infection and injury attributed to detention and patients with worsened chronic conditions or special needs conditions. Clinicians also provided details regarding sentinel cases, categorized into the following themes: Pregnant women, Children, Mentally Ill, COVID-19, and Other serious health issue. Conclusions This is the first survey, to our knowledge, of health care professionals treating individuals upon release from detention. Due to the lack of transparency by federal entities and limited access to detainees, this survey serves as a source of credible information about conditions experienced within immigration detention facilities and is a means of corroborating immigrant testimonials and media reports. These findings can help inform policy discussions regarding systematic changes to the delivery of healthcare in detention, quality assurance and transparent reporting

Associations of military divorce with mental, behavioral, and physical health outcomes

Background Divorce has been linked with poor physical and mental health outcomes among civilians. Given the unique stressors experienced by U.S. service members, including lengthy and/or multiple deployments, this study aimed to examine the associations of recent divorce on health and military outcomes among a cohort of U.S. service members. Methods Millennium Cohort participants from the first enrollment panel, married at baseline (2001–2003), and married or divorced at follow-up (2004–2006), (N = 29,314). Those divorced were compared to those who remained married for mental, behavioral, physical health, and military outcomes using logistic regression models. Results Compared to those who remained married, recently divorced participants were significantly more likely to screen positive for new-onset posttraumatic stress disorder, depression, smoking initiation, binge drinking, alcohol-related problems, and experience moderate weight gain. However, they were also more likely be in the highest 15thpercentile of physical functioning, and be able to deploy within the subsequent 3-year period after divorce. Conclusions Recent divorce among military members was associated with adverse mental health outcomes and risky behaviors, but was also associated with higher odds of subsequent deployment. Attention should be given to those recently divorced regarding mental health and substance abuse treatment and prevention strategies

Dissolution-guided wetting for microarray and microfluidic devices

The trapping of air bubbles presents a substantial impediment for the user in the increasingly widespread use of lab-on-a-chip products having microcavities in the forms of microwells, traps, dead ends and corners. Here we demonstrate a simple, effective, and passive method to eliminate air bubbles by coating hydrophilized microarray and microfluidic devices with a monosaccharide such as D-glucose or D-sorbitol, where the microcavities are filled with a conformal, elliptical, cone-shaped monosaccharide solid. These devices were stored in air for up to 6 months with a complete rewetting of the microcavities by dissolution of the monosaccharide with an aqueous solution

Glass wool: a novel support for heterogeneous catalysis

[EN] Heterogeneous catalysis presents significant advantages over homogeneous catalysis such as ease of separation and reuse of the catalyst. Here we show that a very inexpensive, manageable and widely available material - glass wool - can act as a catalyst support for a number of different reactions. Different metal and metal oxide nanoparticles, based on Pd, Co, Cu, Au and Ru, were deposited on glass wool and used as heterogeneous catalysts for a variety of thermal and photochemical organic reactions including reductive de-halogenation of aryl halides, reduction of nitrobenzene, Csp(3)-Csp(3) couplings, N-C heterocycloadditions (click chemistry) and Csp-Csp(2) couplings (Sonogashira couplings). The use of glass wool as a catalyst support for important organic reactions, particularly C-C couplings, opens the opportunity to develop economical heterogeneous catalysts with excellent potential for flow photo-chemistry application.This work was supported by the Natural Sciences and Engineering Research Council of Canada, the Canada Foundation for Innovation, the Canada Research Chairs Program and funding from Canada's International Development Research Centre (IDRC). Thanks are due to the RISE program for the scholarship awarded to M. C. and the Generalitat Valenciana (BEST/2017/049) for the financial support granted to M. L. M. The authors would like to thank Dr Yun Liu for helping on the acquisition of the SEM images.Elhage, A.; Wang, B.; Marina, N.; Marín García, ML.; Cruz, M.; Lanterna, AE.; Scaiano, JC. (2018). Glass wool: a novel support for heterogeneous catalysis. Chemical Science. 9(33):6844-6852. https://doi.org/10.1039/c8sc02115eS68446852933Davies, I. 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R., Hävecker, M., Knop-Gericke, A., & Schlögl, R. (2014). A near ambient pressure XPS study of Au oxidation. Physical Chemistry Chemical Physics, 16(17), 7881. doi:10.1039/c4cp00308jHigman, C. S., Lanterna, A. E., Marin, M. L., Scaiano, J. C., & Fogg, D. E. (2016). Catalyst Decomposition during Olefin Metathesis Yields Isomerization-Active Ruthenium Nanoparticles. ChemCatChem, 8(15), 2446-2449. doi:10.1002/cctc.201600738Bedford, R. B., Cazin, C. S. J., & Holder, D. (2004). The development of palladium catalysts for CC and Cheteroatom bond forming reactions of aryl chloride substrates. Coordination Chemistry Reviews, 248(21-24), 2283-2321. doi:10.1016/j.ccr.2004.06.012CRC Handbook of Chemistry and Physics , ed. D. R. Lide , Taylor and Francis Group , Boca Raton, FL , 88th edn, 2007 , p. 2640Sahoo, B., Surkus, A.-E., Pohl, M.-M., Radnik, J., Schneider, M., Bachmann, S., … Beller, M. (2017). A Biomass-Derived Non-Noble Cobalt Catalyst for Selective Hydrodehalogenation of Alkyl and (Hetero)Aryl Halides. Angewandte Chemie, 129(37), 11394-11399. doi:10.1002/ange.201702478Devery, J. J., Nguyen, J. D., Dai, C., & Stephenson, C. R. J. (2016). Light-Mediated Reductive Debromination of Unactivated Alkyl and Aryl Bromides. ACS Catalysis, 6(9), 5962-5967. doi:10.1021/acscatal.6b01914Liao, L., Zhang, Q., Su, Z., Zhao, Z., Wang, Y., Li, Y., … Bao, J. (2013). Efficient solar water-splitting using a nanocrystalline CoO photocatalyst. Nature Nanotechnology, 9(1), 69-73. doi:10.1038/nnano.2013.272Hainer, A. S., Hodgins, J. S., Sandre, V., Vallieres, M., Lanterna, A. E., & Scaiano, J. C. (2018). Photocatalytic Hydrogen Generation Using Metal-Decorated TiO2: Sacrificial Donors vs True Water Splitting. ACS Energy Letters, 3(3), 542-545. doi:10.1021/acsenergylett.8b00152Elhage, A., Lanterna, A. E., & Scaiano, J. C. (2018). 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Journal of the American Chemical Society, 128(50), 15980-15981. doi:10.1021/ja066522

Knee Osteoarthritis, Potential Mediators, and Risk of All-Cause Mortality: Data From the Osteoarthritis Initiative.

ObjectiveTo assess the relation of symptomatic knee osteoarthritis (OA), knee pain, and radiographic knee OA to All-cause mortality and to identify mediators in the causal pathway.MethodsParticipants from the Osteoarthritis Initiative were divided into 4 groups: 1) symptomatic knee OA (i.e., both radiographic knee OA [Kellgren/Lawrence grade ≥2] and knee pain); 2) knee pain only; 3) radiographic knee OA only; and 4) neither radiographic knee OA nor knee pain. We examined the relation of knee OA status to All-cause mortality using a multivariable Cox proportional hazards model and assessed the extent to which the association was mediated by disability, physical component summary (PCS) and mental component summary (MCS) scores for quality of life (QoL), and use of oral pain-relief medications (i.e., nonsteroidal antiinflammatory drugs and opioids).ResultsAmong 4,796 participants, 282 died over the 96-month follow-up period. Compared with those with neither radiographic knee OA nor knee pain, multivariable-adjusted hazard ratios (HRs) of mortality were 2.2 (95% confidence interval [95% CI] 1.6-3.1) for symptomatic knee OA, 0.9 (95% CI 0.6-1.4) for knee pain only, and 2.0 (95% CI 1.4-2.9) for radiographic knee OA only, respectively. Indirect effects (HRs) of symptomatic knee OA on mortality via disability and PCS of QoL were 1.1 (95% CI 1.0-1.4) and 1.2 (95% CI 1.0-1.4), respectively. No apparent mediation effect was observed through either MCS of QoL or oral pain-relief medications use.ConclusionParticipants with either symptomatic or radiographic knee OA were at an increased risk of All-cause mortality. Increased risk of mortality from symptomatic knee OA was partially mediated through its effect on disability and PCS of QoL

Essential functions of p21-activated kinase 1 in morphogenesis and differentiation of mammary glands

Although growth factors have been shown to influence mammary gland development, the nature of downstream effectors remains elusive. In this study, we show that the expression of p21-activated kinase (Pak)1, a serine/threonine protein kinase, is activated in mammary glands during pregnancy and lactation. By targeting an ectopic expression of a kinase-dead Pak1 mutant under the control of ovine β-lactoglobulin promoter, we found that the mammary glands of female mice expressing kinase-dead Pak1 transgene revealed incomplete lobuloalveolar development and impaired functional differentiation. The expression of whey acidic protein and β-casein and the amount of activated Stat5 in the nuclei of epithelial cells in transgenic mice were drastically reduced. Further analysis of the underlying mechanisms revealed that Pak1 stimulated β-casein promoter activity in normal mouse mammary epithelial cells and also cooperated with Stat5a. Pak1 directly interacted with and phosphorylated Stat5a at Ser 779, and both COOH-terminal deletion containing Ser 779 of Stat5a and the Ser 779 to Ala mutation completely prevented the ability of Pak1 to stimulate β-casein promoter. Mammary glands expressing inactive Pak1 exhibited a reduction of Stat5a Ser 779 phosphorylation. These findings suggest that Pak1 is required for alveolar morphogenesis and lactation function, and thus, identify novel functions of Pak1 in the mammary gland development

Separation of fluorescently labeled phosphoinositides and sphingolipids by capillary electrophoresis

Phosphoinositides (PIs) and sphingolipids regulate many aspects of cell behavior and are often involved in disease processes such as oncogenesis. Capillary electrophoresis with laser induced fluorescence detection (CE-LIF) is emerging as an important tool for enzymatic assays of the metabolism of these lipids, particularly in cell-based formats. Previous separations of phosphoinositide lipids by CE required a complex buffer with polymer additives which had the disadvantages of high cost and/or short shelf life. Further a simultaneous separation of these classes of lipids has not been demonstrated in a robust buffer system. In the current work, a simple separation buffer based on NaH2PO4 and 1-propanol was optimized to separate two sphingolipids and multiple phosphoinositides by CE. The NaH2PO4 concentration, pH, 1-propanol fraction, and a surfactant additive to the buffer were individually optimized to achieve simultaneous separation of the sphingolipids and phosphoinositides. Fluorescein-labeled sphingosine (SFL) and sphingosine 1-phosphate (S1PFL), fluorescein-labeled phosphatidyl-inositol 4,5-bisphosphate (PIP2) and phosphatidyl-inositol 3,4,5-trisphosphate (PIP3), and bodipy-fluorescein (BFL)-labeled PIP2 and PIP3 were separated pairwise and in combination to demonstrate the generalizability of the method. Theoretical plate numbers achieved were as high as 2×105 in separating fluorophore-labeled PIP2 and PIP3. Detection limits for the 6 analytes were in the range of 10−18 to 10−20 mol. The method also showed high reproducibility, as the relative standard deviation of the normalized migration time for each analyte in the simultaneous separation of all 6 compounds was less than 1%. The separation of a mixture composed of diacylglycerol (DAG) and multiple phosphoinositides was also demonstrated. As a final test, fluorescent lipid metabolites formed within cells loaded with BFLPIP2 were separated from a cell lysate as well as a single cell. This simple and robust separation method for SFL and S1PFL and various metabolites of phosphoinositide-related signal transduction is expected to enable improved enzymatic assays for biological and clinical applications

Childhood Development after Cochlear Implantation (CDaCI) study: Design and baseline characteristics

Children with severe to profound sensorineural hearing loss face communication challenges that influence language, psychosocial and scholastic performance. Clinical studies over the past 20 years have supported wider application of cochlear implants in children. The Childhood Development after Cochlear Implantation (CDaCI) study is the first longitudinal multicentre, national cohort study to evaluate systematically early cochlear implant (CI) outcomes in children. The objective of the study was to compare children who have undergone cochlear implantation, with similarly aged hearing peers across multiple domains, including oral language development, auditory performance, psychosocial and behavioural functioning, and quality of life. The CDaCI study is a multicentre national cohort study of CI children and normal hearing (NH) peers. Eligibility criteria include informed consent, age less than 5 years, pre- or post-lingually deaf, developmental criteria met, commitment to educate the child in English and bilateral cochlear implants. All children had a standardised baseline assessment that included demographics, hearing and medical history, communication history, language measures, cognitive tests, speech recognition, an audiological exam, psychosocial assessment including parent-child videotapes and parent reported quality of life. Follow-up visits are scheduled at six-month intervals and include a standardised assessment of the full battery of measures. Quality assurance activities were incorporated into the design of the study. A total of 188 CI children and 97 NH peers were enrolled between November 2002 and December 2004. The mean age, gender and race of the CI and NH children are comparable. With regard to parental demographics, the CI and NH children's families are statistically different. The parents of CI children are younger, and not as well educated, with 49% of CI parents reporting college graduation vs. 84% of the NH parents. The income of the CI parents is also lower than the NH parents. Assessments of cognition suggest that there may be baseline differences between the CI and NH children; however the scores were high enough to suggest language learning potential. The observed group differences identified these baseline characteristics as potential confounders which may require adjustment in analyses of outcomes. This longitudinal cohort study addresses questions related to high variability in language outcomes. Identifying sources of that variance requires research designs that: characterise potential predictors with accuracy, use samples that adequately power a study, and employ controls and approaches to analysis that limit bias and error. The CDaCI study was designed to generate a more complete picture of the interactive processes of language learning after implantation. Copyright © 2007 John Wiley & Sons, Ltd.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/56091/1/333_ftp.pd