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The SNARE machinery is involved in apical plasma membrane trafficking in MDCK cells.
We have investigated the controversial involvement of components of the SNARE (soluble N-ethyl maleimide-sensitive factor [NSF] attachment protein [SNAP] receptor) machinery in membrane traffic to the apical plasma membrane of polarized epithelial (MDCK) cells. Overexpression of syntaxin 3, but not of syntaxins 2 or 4, caused an inhibition of TGN to apical transport and apical recycling, and leads to an accumulation of small vesicles underneath the apical plasma membrane. All other tested transport steps were unaffected by syntaxin 3 overexpression. Botulinum neurotoxin E, which cleaves SNAP-23, and antibodies against alpha-SNAP inhibit both TGN to apical and basolateral transport in a reconstituted in vitro system. In contrast, we find no evidence for an involvement of N-ethyl maleimide-sensitive factor in TGN to apical transport, whereas basolateral transport is NSF-dependent. We conclude that syntaxin 3, SNAP-23, and alpha-SNAP are involved in apical membrane fusion. These results demonstrate that vesicle fusion with the apical plasma membrane does not use a mechanism that is entirely unrelated to other cellular membrane fusion events, but uses isoforms of components of the SNARE machinery, which suggests that they play a role in providing specificity to polarized membrane traffic
Healthcare Price Transparency: Policy Approaches and Estimated Impacts on Spending
Healthcare price transparency discussions typically focus on increasing patients' access to information about their out-of-pocket costs, but that focus is too narrow and should include other audiences -- physicians, employers, health plans and policymakers -- each with distinct needs and uses for healthcare price information. Greater price transparency can reduce U.S. healthcare spending.For example, an estimated 18 billion over the next decade. While 40 trillionin total projected health spending over the same period. In contrast, using state all-payer claims databases to gather and report hospital-specific prices might reduce spending by an estimated $61 billion over 10 years.The effects of price transparency depend critically on the intended audience, the decision-making context and how prices are presented. And the impact of price transparency can be greatly amplified if target audiences are able and motivated to act on the information. Simply providing prices is insufficient to control spending without other shifts in healthcare financing, including changes in benefit design to make patients more sensitive to price differences among providers and alternative treatments. Other reforms that can amplify the impact of price transparency include shifting from fee-for-service payments that reward providers for volume to payment methods that put providers at risk for spending for episodes of care or defined patient populations. While price transparency alone seems unlikely to transform the healthcare system, it can play a needed role in enabling effective reforms in value-based benefit design and provider payment
Long Island Follows Bumpy New York Road to National Health Reform
At first glance, New York and the Long Island metropolitan area appear well positioned for smooth implementation of the federal Patient Protection and Affordable Care Act (ACA) of 2010, according to a new Center for Studying Health System Change (HSC) study of Long Island's commercial and Medicaid insurance markets (see Data Source). Key ACA reformsâexpanded Medicaid eligibility, premium rating restrictions in the nongroup, or individual, and small-group markets, minimum medical loss ratios (MLRs)âhave long been features of New York's broad public health insurance programs and highly regulated health insurance market. Once the ACA became law, there was little doubt that New York would embrace reform. Yet, partisan gridlock in Albany has made for a rough road to health reform for New York. After many months of wrangling with the state Legislature, Gov. Andrew Cuomo (D) resorted to authorizing the state health insurance exchange by executive order in 2012, giving New York's exchange a later start than in many states. Another threat to successful implementation is the state's commitment to stringent insurance regulations that exceed ACA requirements, most notably in small-group and nongroup community rating. Most respondents expected stricter state regulations to keep New York nongroup premiums very high and lead many healthier state residents to continue staying out of the nongroup risk pool. However, when 2014 premiums were released in July, the approved rates were lower than most had expected. What remains uncertain is how sustainable these rates will be over timeâspecifically, whether they will remain sufficiently low to attract and retain a sizable pool of younger, healthier enrollees
Software Reduces Radio-Interference Effects in Radar Data
A computer program suppresses the effects of narrow-band radio-frequency interference (RFI) on the data collected by a wide-band radar system. The need for this program arises because some advanced wide-band synthetic-aperture radar systems utilize frequency bands that include frequencies used by other radio services. In this program, the RFI environment is represented by an auto-regressive process, the frequency band of which is narrow relative to that of the radar. Most of the RFI signals, both narrow- and wide-band, are estimated in one pass of a least-mean-square (LMS) adaptive filter. The program implements three popular LMS algorithms: the time-domain LMS, the frequency-domain LMS, and the filter-bank LMS adaptive-filter algorithms. The program can be run in a manual or automatic mode. In the manual mode, the user selects the filter parameters prior to execution. In the automatic mode, the program utilizes median-filter and spectral-estimation techniques plus the variable-step-size LMS algorithm for automatic determination of filter parameters, and the parameters are adaptively changed as functions of the inputs, resulting in better overall performance
Changes in the surface energy budget after fire in boreal ecosystems of interior Alaska: An annual perspective
Understanding links between the disturbance regime and regional climate in boreal regions requires observations of the surface energy budget from ecosystems in various stages of secondary succession. While several studies have characterized fireâinduced differences in surface energy fluxes from boreal ecosystems during summer months, much less is known about these differences over the full annual cycle. Here we measured components of the surface energy budget (including both radiative and turbulent fluxes) at three sites from a fire chronosequence in interior Alaska for a 1âyear period. Our sites consisted of large burn scars resulting from fires in 1999, 1987, and âŒ1920 (hereinafter referred to as the 3â, 15â, and 80âyear sites, respectively). Vegetation cover consisted primarily of bunch grasses at the 3âyear site, aspen and willow at the 15âyear site, and black spruce at the 80âyear site. Annual net radiation declined by 31% (17 W m^(â2)) for both the 3â and the 15âyear sites as compared with the 80âyear site (which had an annual mean of 55 W m^(â2)). Annual sensible heat fluxes were reduced by an even greater amount, by 55% at the 3âyear site and by 52% at the 15âyear site as compared with the 80âyear site (which had an annual mean of 21 W m^(â2)). Absolute differences between the postfire ecosystems and the mature black spruce forest for both net radiation and sensible heat fluxes were greatest during spring (because of differences in snow cover and surface albedo), substantial during summer and winter, and relatively small during fall. Fireâinduced disturbance also initially reduced annual evapotranspiration (ET). Annual ET decreased by 33% (99 mm yr^(â1)) at the 3âyear site as compared with the 80âyear site (which had an annual flux of 301 mm yr^(â1)). Annual ET at the 15âyear site (283 mm yr^(â1)) was approximately the same as that from the 80âyear site, even though the 15âyear site had substantially higher ET during July. Our study suggests that differences in annual ET between deciduous and conifer stands may be smaller than that inferred solely from summer observations. This study provides a direct means to validate land surface processes in global climate models attempting to capture vegetationâclimate feedbacks in northern terrestrial regions
More than just hormones: H295R cells as predictors of reproductive toxicity
AbstractMany of the commonly observed reproductive toxicities associated with therapeutic compounds can be traced to a disruption of the steroidogenic pathway. We sought to develop an in vitro assay that would predict reproductive toxicity and be high throughput in nature. H295R cells, previously validated as having an intact and functional steroidogenic pathway, were treated with 83 known-positive and 79 known-negative proprietary and public-domain compounds. The assay measured the expression of the key enzymes STAR, 3ÎČHSD2, CYP17A1, CYP11B2, CYP19A1, CYP21A2, and CYP11A1 and the hormones DHEA, progesterone, testosterone, and cortisol. We found that a Random Forest model yielded a receiver operating characteristic area under the curve (ROC AUC) of 0.845, with sensitivity of 0.724 and specificity of 0.758 for predicting in vivo reproductive toxicity with this in vitro assay system
PETAAL : Protection Environnement et Technologie des Arbres dâAlignements
Programme dâĂ©tudes coordonnĂ© par le centre technique Plante & CitĂ©
Avec le soutien du Fond Unique Interministériel et du Conseil Régional des Pays de la Loir
PETAAL Protection of border tree environment and technology
The sycamore lace bug has been identified as one of the main phytosanitary problems for managers of tree-planted heritage sites within green areas in 36,000 French regional authorities. The spread of this pest nationally and the predominance of sycamores in towns makes the bug one of the first pests to receive phytosanitary intervention in our green spaces. The move from chemical control, which is currently used, to biological control is governed by environmental and societal issues and embodies ongoing major technical innovation within green areas
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