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Deconstruction of plant biomass by a Cellulomonas strain isolated from an ultra-basic (lignin-stripping) spring.
Plant material falling into the ultra-basic (pH 11.5-11.9) springs within The Cedars, an actively serpentinizing site in Sonoma County, California, is subject to conditions that mimic the industrial pretreatment of lignocellulosic biomass for biofuel production. We sought to obtain hemicellulolytic/cellulolytic bacteria from The Cedars springs that are capable of withstanding the extreme alkaline conditions wherein calcium hydroxide-rich water removes lignin, making cell wall polysaccharides more accessible to microorganisms and their enzymes. We enriched for such bacteria by adding plant debris from the springs into a synthetic alkaline medium with ground tissue of the biofuel crop switchgrass (Panicum virgatum L.) as the sole source of carbon. From the enrichment culture we isolated the facultative anaerobic bacterium Cellulomonas sp. strain FA1 (NBRC 114238), which tolerates high pH and catabolizes the major plant cell wall-associated polysaccharides cellulose, pectin, and hemicellulose. Strain FA1 in monoculture colonized the plant material and degraded switchgrass at a faster rate than the community from which it was derived. Cells of strain FA1 could be acclimated through subculturing to grow at a maximal concentration of 13.4% ethanol. A strain FA1-encoded β-1, 4-endoxylanase expressed in E. coli was active at a broad pH range, displaying near maximal activity at pH 6-9. Discovery of this bacterium illustrates the value of extreme alkaline springs in the search for microorganisms with potential for consolidated bioprocessing of plant biomass to biofuels and other valuable bio-inspired products
Arsenic and cadmium contents in Brazilian rice from different origins can vary more than two orders of magnitude
Acknowledgements The authors wish to thank the National Council for Scientific and Technological Development (CNPq) and Coordination for the Improvement of Higher Education Personnel (CAPES) for the financial support.Peer reviewedPostprin
Manufacturing-focused emissions reductions in footwear production
What is the burden upon your feet? With sales of running and jogging shoes in the world averaging a nontrivial 25 billion shoes per year, or 34 million per day, the impact of the footwear industry represents a significant portion of the apparel sector's environmental burden. A single shoe can contain 65 discrete parts that require 360 processing steps for assembly. While brand name companies dictate product design and material specifications, the actual manufacturing of footwear is typically contracted to manufacturers based in emerging economies. Using life cycle assessment methodology in accordance with the ISO 14040/14044 standards, this effort quantifies the life cycle greenhouse gas emissions, often referred to as a carbon footprint, of a pair of running shoes. Furthermore, mitigation strategies are proposed focusing on high leverage aspects of the life cycle.
Using this approach, it is estimated that the carbon footprint of a typical pair of running shoes made of synthetic materials is 14 ± 2.7 kg CO[subscript 2]-equivalent. The vast majority of this impact is incurred during the materials processing and manufacturing stages, which make up around 29% and 68% of the total impact, respectively. Other similar studies in the apparel industry have reported carbon footprints of running shoes ranging between 18 and 41 kg CO[subscript 2]-equivalent/pair (PUMA, 2008; Timberland, 2009).
For consumer products not requiring electricity during use, the intensity of emissions in the manufacturing phase is atypical; most commonly, materials make up the biggest percentage of impact. This distinction highlights the importance of identifying mitigation strategies within the manufacturing process, and the need to evaluate the emissions reduction efficacy of each potential strategy. By suggesting a few of the causes of manufacturing dominance in the global warming potential assessment of this product, this study hypothesizes the characteristics of a product that could lead to high manufacturing impact. Some of these characteristics include the source of energy in manufacturing and the form of manufacturing, in other words the complexity of processes used and the area over which these process are performed (particularly when a product involves numerous parts and light materials). Thereby, the work provides an example when relying solely on the bill of materials information for product greenhouse gas emissions assessment may underestimate life cycle burden and ignore potentially high impact mitigation strategies
Voltage-dependent Anion Channel-1 (VDAC-1) Contributes to ATP Release and Cell Volume Regulation in Murine Cells
Extracellular ATP regulates several elements of the mucus clearance process important for pulmonary host defense. However, the mechanisms mediating ATP release onto airway surfaces remain unknown. Mitochondrial voltage-dependent anion channels (mt-VDACs) translocate a variety of metabolites, including ATP and ADP, across the mitochondrial outer membrane, and a plasmalemmal splice variant (pl-VDAC-1) has been proposed to mediate ATP translocation across the plasma membrane. We tested the involvement of VDAC-1 in ATP release in a series of studies in murine cells. First, the full-length coding sequence was cloned from a mouse airway epithelial cell line (MTE7b−) and transfected into NIH 3T3 cells, and pl-VDAC-1-transfected cells exhibited higher rates of ATP release in response to medium change compared with mock-transfected cells. Second, ATP release was compared in cells isolated from VDAC-1 knockout [VDAC-1 (−/−)] and wild-type (WT) mice. Fibroblasts from VDAC-1 (−/−) mice released less ATP than WT mice in response to a medium change. Well-differentiated cultures from nasal and tracheal epithelia of VDAC-1 (−/−) mice exhibited less ATP release in response to luminal hypotonic challenge than WT mice. Confocal microscopy studies revealed that cell volume acutely increased in airway epithelia from both VDAC-1 (−/−) and WT mice after luminal hypotonic challenge, but VDAC-1 (−/−) cells exhibited a slower regulatory volume decrease (RVD) than WT cells. Addition of ATP or apyrase to the luminal surface of VDAC-1 (−/−) or WT cultures with hypotonic challenge produced similar initial cell height responses and RVD kinetics in both cell types, suggesting that involvement of VDAC-1 in RVD is through ATP release. Taken together, these studies suggest that VDAC-1, directly or indirectly, contributes to ATP release from murine cells. However, the observation that VDAC-1 knockout cells released a significant amount of ATP suggests that other molecules also play a role in this function
Bond-dependent anisotropy and magnon breakdown in cobalt Kitaev triangular antiferromagnet
The Kitaev model, a honeycomb network of spins with bond-dependent
anisotropic interactions, is a rare example of having a quantum spin liquid
ground state. Although most Kitaev model candidate materials eventually order
magnetically due to inevitable non-Kitaev terms, their bond-dependent
anisotropy manifests in unusual spin dynamics. It has recently been suggested
that bond-dependent anisotropy can stabilise novel magnetic phases and exotic
spin dynamics on the geometrically frustrated triangular lattice. However, few
materials have been identified with simultaneous geometric frustration and
bond-dependent anisotropy. Here, we report a frustrated triangular lattice with
bond-dependent anisotropy in the cobalt-based triangular van der Waals
antiferromagnet CoI2. Its momentum and energy-resolved spin dynamics exhibit
substantial magnon breakdown and complex level repulsion, as measured by
inelastic neutron scattering. A thorough examination of excitations in both the
paramagnetic and magnetically ordered states reveals that the bond-dependent
anisotropy is the origin of the spiral order and the magnon breakdown found in
CoI2. Our result paves the way toward a new research direction for the Kitaev
model with geometrical frustration.Comment: 13 pages, 4 figures, Under revie
Trends and determinants of underweight and overweight/obesity among urban Ethiopian women from 2000 to 2016
Background: Nutritional, epidemiological and demographic transitions have been associated with the emergence of the double burden of malnutrition globally. In Ethiopia, there has been no nationally representative investigation of trends and determinants of both underweight and overweight/obesity among urban women. This study examined the trends and determinants of underweight and overweight/obesity in urban Ethiopian women from 2000 to 2016. Methods: Trends in the prevalence of underweight and overweight/obesity were investigated based on a series of the Ethiopia Demographic and Health Survey (EDHS) data for the years 2000 (n = 2559), 2005 (n = 1112), 2011 (n = 3569), and 2016 (n = 3106). Multivariable multinomial logistic regression was used to investigate the association between socioeconomic, demographic, behavioural, and community-level factors with underweight and overweight/obesity. Results: The prevalence of underweight in urban Ethiopian women reduced significantly from 23.2% (95% confidence interval [CI]: 20.3, 26.3%) in 2000 to 14.8% (95% CI: 13.1, 16.7%) in 2016, while overweight/obesity increased significantly from 10.9% (95% CI: 9.1, 13.0%) in 2000 to 21.4% (95% CI: 18.2, 25.1%) in 2016. Urban women from rich households and those who had never married were less likely to be underweight. Urban women who were from wealthy households and those who attained at least secondary education were more likely to be overweight/obese. Women who were informally employed and listened to the radio were less likely to be overweight/obese compared to those who were unemployed and did not listen to the radio, respectively. Conclusion: The prevalence of overweight/obesity increased from 2000 to 2016, with a concurrent reduction in the prevalence of underweight. Interventions aiming to reduce overweight and obesity should target urban women with higher education, those who resided in wealthier households and those who watched the television
Physiological Regulation of ATP Release at the Apical Surface of Human Airway Epithelia
Extracellular ATP and its metabolite adenosine regulate mucociliary clearance in airway epithelia. Little has been known, however, regarding the actual ATP and adenosine concentrations in the thin (~7 μm) liquid layer lining native airway surfaces and the link between ATP release/metabolism and autocrine/paracrine regulation of epithelial function. In this study, chimeric Staphylococcus aureus protein A-luciferase (SPA-luc) was bound to endogenous antigens on primary human bronchial epithelial (HBE) cell surface and ATP concentrations assessed in real-time in the thin airway surface liquid (ASL). ATP concentrations on resting cells were 1–10 nM. Inhibition of ecto-nucleotidases resulted in ATP accumulation at a rate of ~250 fmol/min/cm2, reflecting the basal ATP release rate. Following hypotonic challenge to promote cell swelling, cell-surface ATP concentration measured by SPA-luc transiently reached ~1 μM independent of ASL volume, reflecting a transient 3-log increase in ATP release rates. In contrast, peak ATP concentrations measured in bulk ASL by soluble luciferase inversely correlated with volume. ATP release rates were intra-cellular calcium-independent, suggesting that non-exocytotic ATP release from ciliated cells, which dominate our cultures, mediated hypotonicity-induced nucleotide release. However, the cystic fibrosis transmembrane conductance regulator (CFTR) did not participate in this function. Following the acute swelling phase, HBE cells exhibited regulatory volume decrease which was impaired by apyrase and facilitated by ATP or UTP. Our data provide the first evidence that ATP concentrations at the airway epithelial surface reach the range for P2Y2 receptor activation by physiological stimuli and identify a role for mucosal ATP release in airway epithelial cell volume regulation
Outcomes and risk score for distal pancreatectomy with celiac axis resection (DP-CAR) : an international multicenter analysis
Background: Distal pancreatectomy with celiac axis resection (DP-CAR) is a treatment option for selected patients with pancreatic cancer involving the celiac axis. A recent multicenter European study reported a 90-day mortality rate of 16%, highlighting the importance of patient selection. The authors constructed a risk score to predict 90-day mortality and assessed oncologic outcomes.
Methods: This multicenter retrospective cohort study investigated patients undergoing DP-CAR at 20 European centers from 12 countries (model design 2000-2016) and three very-high-volume international centers in the United States and Japan (model validation 2004-2017). The area under receiver operator curve (AUC) and calibration plots were used for validation of the 90-day mortality risk model. Secondary outcomes included resection margin status, adjuvant therapy, and survival.
Results: For 191 DP-CAR patients, the 90-day mortality rate was 5.5% (95 confidence interval [CI], 2.2-11%) at 5 high-volume (1 DP-CAR/year) and 18% (95 CI, 9-30%) at 18 low-volume DP-CAR centers (P=0.015). A risk score with age, sex, body mass index (BMI), American Society of Anesthesiologists (ASA) score, multivisceral resection, open versus minimally invasive surgery, and low- versus high-volume center performed well in both the design and validation cohorts (AUC, 0.79 vs 0.74; P=0.642). For 174 patients with pancreatic ductal adenocarcinoma, the R0 resection rate was 60%, neoadjuvant and adjuvant therapies were applied for respectively 69% and 67% of the patients, and the median overall survival period was 19months (95 CI, 15-25months).
Conclusions: When performed for selected patients at high-volume centers, DP-CAR is associated with acceptable 90-day mortality and overall survival. The authors propose a 90-day mortality risk score to improve patient selection and outcomes, with DP-CAR volume as the dominant predictor
Nucleotide Release Provides a Mechanism for Airway Surface Liquid Homeostasis
Nucleotides within the airway surface liquid (ASL) regulate airway epithelial ion transport rates by Ca2+- and protein kinase C-dependent mechanisms via activation of specific P2Y receptors. Extracellular adenine nucleotides also serve as precursors for adenosine, which promotes cyclic AMP-mediated activation of the cystic fibrosis transmembrane regulator chloride channel via A2b adenosine receptors. A biological role for extracellular ATP in ASL volume homeostasis has been suggested by the demonstration of regulated ATP release from airway epithelia. However, nucleotide hydrolysis at the airway surface makes it difficult to assess the magnitude of ATP release and the relative abundance of adenyl purines and, hence, to define their biological functions. We have combined ASL microsampling and high performance liquid chromatography analysis of fluorescent 1,N6-ethenoadenine derivatives to measure adenyl purines in ASL. We found that adenosine, AMP, and ADP accumulated in high concentrations relative to ATP within the ASL covering polarized primary human normal or cystic fibrosis airway epithelial cells. By using immortalized epithelial cell monolayers that endogenously express a luminal A2b adenosine receptor, we found that basal as well as forskolin-promoted cyclic AMP production was reduced by exogenous adenosine deaminase, suggesting that A2b receptors sense endogenous adenosine within the ASL. The physiological role of adenosine was further established by illustrating that adenosine removal or inhibition of adenosine receptors in primary cultures impaired ASL volume regulation. Our data reveal a complex pattern of nucleotides/nucleosides in ASL under resting conditions and suggest that adenosine may play a key role in regulating ASL volume homeostasis
Mutation site-specific differences in arrhythmic risk and sensitivity to sympathetic stimulation in the LQT1 form of congenital long QT syndrome Multicenter study in Japan
AbstractObjectivesWe sought to compare the arrhythmic risk and sensitivity to sympathetic stimulation of mutations located in transmembrane regions and C-terminal regions of the KCNQ1channel in the LQT1 form of congenital long QT syndrome (LQTS).BackgroundThe LQT1 syndrome is frequently manifested with variable expressivity and incomplete penetrance and is much more sensitive to sympathetic stimulation than the other forms.MethodsSixty-six LQT1 patients (27 families) with a total of 19 transmembrane mutations and 29 patients (10 families) with 8 C-terminal mutations were enrolled from five Japanese institutes.ResultsPatients with transmembrane mutations were more frequently affected based on electrocardiographic (ECG) diagnostic criteria (82% vs. 24%, p < 0.0001) and had more frequent LQTS-related cardiac events (all cardiac events: 55% vs. 21%, p = 0.002; syncope: 55% vs. 21%, p = 0.002; aborted cardiac arrest or unexpected sudden cardiac death: 15% vs. 0%, p = 0.03) than those with C-terminal mutations. Patients with transmembrane mutations had a greater risk of first cardiac events occurring at an earlier age, with a hazard ratio of 3.4 (p = 0.006) and with an 8% increase in risk per 10-ms increase in corrected Q-Tend. The baseline ECG parameters, including Q-Tend, Q-Tpeak, and Tpeak-end intervals, were significantly greater in patients with transmembrane mutations than in those with C-terminal mutations (p < 0.005). Moreover, the corrected Q-Tend and Tpeak-end were more prominently increased with exercise in patients with transmembrane mutations (p < 0.005).ConclusionsIn this multicenter Japanese population, LQT1 patients with transmembrane mutations are at higher risk of congenital LQTS-related cardiac events and have greater sensitivity to sympathetic stimulation, as compared with patients with C-terminal mutations
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