19 research outputs found
High temperatures and low soil moisture synergistically reduce switchgrass yields from marginal field sites and inhibit fermentation
‘Marginal lands’ are low productivity sites abandoned from agriculture for reasons such as low or high soil water content, challenging topography, or nutrient deficiency. To avoid competition with crop production, cellulosic bioenergy crops have been proposed for cultivation on marginal lands, however on these sites they may be more strongly affected by environmental stresses such as low soil water content. In this study we used rainout shelters to induce low soil moisture on marginal lands and determine the effect of soil water stress on switchgrass growth and the subsequent production of bioethanol. Five marginal land sites that span a latitudinal gradient in Michigan and Wisconsin were planted to switchgrass in 2013 and during the 2018–2021 growing seasons were exposed to reduced precipitation under rainout shelters in comparison to ambient precipitation. The effect of reduced precipitation was related to the environmental conditions at each site and biofuel production metrics (switchgrass biomass yields and composition and ethanol production). During the first year (2018), the rainout shelters were designed with 60% rain exclusion, which did not affect biomass yields compared to ambient conditions at any of the field sites, but decreased switchgrass fermentability at the Wisconsin Central–Hancock site. In subsequent years, the shelters were redesigned to fully exclude rainfall, which led to reduced biomass yields and inhibited fermentation for three sites. When switchgrass was grown in soils with large reductions in moisture and increases in temperature, the potential for biofuel production was significantly reduced, exposing some of the challenges associated with producing biofuels from lignocellulosic biomass grown under drought conditions
Endovascular strategy or open repair for ruptured abdominal aortic aneurysm: one-year outcomes from the IMPROVE randomized trial.
AIMS: To report the longer term outcomes following either a strategy of endovascular repair first or open repair of ruptured abdominal aortic aneurysm, which are necessary for both patient and clinical decision-making. METHODS AND RESULTS: This pragmatic multicentre (29 UK and 1 Canada) trial randomized 613 patients with a clinical diagnosis of ruptured aneurysm; 316 to an endovascular first strategy (if aortic morphology is suitable, open repair if not) and 297 to open repair. The principal 1-year outcome was mortality; secondary outcomes were re-interventions, hospital discharge, health-related quality-of-life (QoL) (EQ-5D), costs, Quality-Adjusted-Life-Years (QALYs), and cost-effectiveness [incremental net benefit (INB)]. At 1 year, all-cause mortality was 41.1% for the endovascular strategy group and 45.1% for the open repair group, odds ratio 0.85 [95% confidence interval (CI) 0.62, 1.17], P = 0.325, with similar re-intervention rates in each group. The endovascular strategy group and open repair groups had average total hospital stays of 17 and 26 days, respectively, P < 0.001. Patients surviving rupture had higher average EQ-5D utility scores in the endovascular strategy vs. open repair groups, mean differences 0.087 (95% CI 0.017, 0.158), 0.068 (95% CI -0.004, 0.140) at 3 and 12 months, respectively. There were indications that QALYs were higher and costs lower for the endovascular first strategy, combining to give an INB of £3877 (95% CI £253, £7408) or €4356 (95% CI €284, €8323). CONCLUSION: An endovascular first strategy for management of ruptured aneurysms does not offer a survival benefit over 1 year but offers patients faster discharge with better QoL and is cost-effective. CLINICAL TRIAL REGISTRATION: ISRCTN 48334791
The effect of aortic morphology on peri-operative mortality of ruptured abdominal aortic aneurysm
Aims
To investigate whether aneurysm shape and extent, which indicate whether a patient with ruptured abdominal aortic aneurysm (rAAA) is eligible for endovascular repair (EVAR), influence the outcome of both EVAR and open surgical repair.
Methods and results
The influence of six morphological parameters (maximum aortic diameter, aneurysm neck diameter, length and conicality, proximal neck angle, and maximum common iliac diameter) on mortality and reinterventions within 30 days was investigated in rAAA patients randomized before morphological assessment in the Immediate Management of the Patient with Rupture: Open Versus Endovascular strategies (IMPROVE) trial. Patients with a proven diagnosis of rAAA, who underwent repair and had their admission computerized tomography scan submitted to the core laboratory, were included. Among 458 patients (364 men, mean age 76 years), who had either EVAR (n = 177) or open repair (n = 281) started, there were 155 deaths and 88 re-interventions within 30 days of randomization analysed according to a pre-specified plan. The mean maximum aortic diameter was 8.6 cm. There were no substantial correlations between the six morphological variables. Aneurysm neck length was shorter in those undergoing open repair (vs. EVAR). Aneurysm neck length (mean 23.3, SD 16.1 mm) was inversely associated with mortality for open repair and overall: adjusted OR 0.72 (95% CI 0.57, 0.92) for each 16 mm (SD) increase in length. There were no convincing associations of morphological parameters with reinterventions.
Conclusion
Short aneurysm necks adversely influence mortality after open repair of rAAA and preclude conventional EVAR. This may help explain why observational studies, but not randomized trials, have shown an early survival benefit for EVAR.
Clinical trial registration: ISRCTN 48334791
Recommended from our members
Roles of Sialic Acid Diversity in Mammalian Brain Evolution /
The sialic acids N-acetylneuraminic acid (Neu5Ac) and N- glycolylneuraminic acid (Neu5Gc) are commonly found in the glycolipids and glycoproteins that cover all vertebrate cell surfaces. The brain, which has a higher concentration of sialic acids than any other tissue, exhibits some interesting features of sialic acid biology with evolutionary implications. In the brain of all vertebrate species tested to date, Neu5Ac is present at high quantities, whereas Neu5Gc is very low or even absent. This conserved exclusion suggests a selective pressure against Neu5Gc expression in the vertebrate brain. We have hypothesized that the mechanism for this pressure may be that Neu5Gc presence inhibits the appropriate enzymatic degradation of polysialic acid (polySia), a polymer of alpha2-8 linked sialic acid. PolySia is primarily found in brain tissue, and has been implicated in a wide array of important developmental processes including migration, neurite outgrowth, plasticity, and repair. In Chapter 3, we test the viability of this hypothesis in vitro. We demonstrate that Neu5Gc present in polySia does in fact exhibit a relative resistance to degradation by vertebrate and bacterial sialidases. To determine whether this process is meaningful in vivo, and to further understand the presumed detrimental effects of Neu5Gc on the vertebrate brain, we have developed transgenic mouse models that overexpress Neu5Gc in brain tissue. In Chapter 4, we describe these ongoing efforts. Studies in the near future will determine whether these mice exhibit problems with polySia degradation, and comprehensively characterize their behavioral and anatomical phenotypes. Lastly, in Chapter 5, we explore the potential role of polySia in human brain evolution. We focus on the effects of a single human-specific mutation in one of the biosynthetic enzymes of polySia, ST8Sia-II. Preliminary work suggests that this mutation decreases the stability of the enzyme while increasing the length of its synthesized polySia product. These effects may have implications for the regulation of polySia, and its associated processes, in the human brain. Together, the work discussed here examines potential roles that sialic acid metabolism may have played in mammalian brain evolutio
Synthesis, growth, crystalline perfection of 4-bromo-4′dimethylamino benzylideneaniline (BDMABA) and photons absorption of BDMABA crystal
One of the Schiff base 4-bromo-4'dimethylamino benzylideneaniline (BDMABA) compounds was synthesized and single crystal of the material was grown by solvent evaporation method at room temperature. Molecular structure of BDMABA was confirmed by H-1 nuclear magnetic resonance and the presence of functional groups was confirmed by Fourier Transform Infrared and Fourier Transform Raman spectral analyses. Cell parameters were determined using single crystal X-ray diffraction analysis and crystalline perfection of the grown BDMABA crystal was evaluated using high-resolution X-ray diffraction analysis. Thermal analyses indicated that the material is thermally stable up to 215 degrees C and its melting point is 161.5 degrees C. Vickers microhardness study was carried out to estimate the mechanical hardness of BDMABA crystal which shows that the crystal belongs to the class of soft materials. Linear and nonlinear optical studies were carried out using UV-vis-NIR spectrum and open aperture Z-scan technique respectively
A Mycobacterium tuberculosis Specific IgG3 Signature of Recurrent Tuberculosis
South Africa has the highest prevalence of HIV and tuberculosis (TB) co-infection globally. Recurrent TB, caused by relapse or reinfection, makes up the majority of TB cases in South Africa, and HIV infected individuals have a greater likelihood of developing recurrent TB. Given that TB remains a leading cause of death for HIV infected individuals, and correlates of TB recurrence protection/risk have yet to be defined, here we sought to understand the antibody associated mechanisms of recurrent TB by investigating the humoral response in a longitudinal cohort of HIV co-infected individuals previously treated for TB with and without recurrent disease during follow-up, in order to identify antibody correlates of protection between individuals who do not have recurrent TB and individuals who do. We used a high-throughput, “systems serology” approach to profile biophysical and functional characteristics of antibodies targeting antigens from Mycobacterium tuberculosis (Mtb). Differences in antibody profiles were noted between individuals with and without recurrent TB, albeit these differences were largely observed close to the time of re-diagnosis. Individuals with recurrent TB had decreased Mtb-antigen specific IgG3 titers, but not other IgG subclasses or IgA, compared to control individuals. These data point to a potential role for Mtb-specific IgG3 responses as biomarkers or direct mediators of protective immunity against Mtb recurrence.</jats:p
QFT/Mtb-specific IgG data
Raw dataset related to the titled paper showing unidentified study participants, and their multiple raw datasets which includes, HIV status, CD4 count, Viral load, QFT status, QFT results, multiple Mtb-specific antigens IgGs levels, and total IgG.</p
More than happiness: Aliveness and struggle in lesbian, gay, bisexual, trans and queer lives
IFN-γ independent markers of Mycobacterium tuberculosis exposure among male South African gold minersResearch in context
Summary: Background: The prevalence of tuberculosis among men who work in the gold mines of South Africa is among the highest in the world, but a fraction of miners demonstrate consistently negative results upon tuberculin skin test (TST) and IFN-γ release assay (IGRA). We hypothesized that these “resisters” (RSTRs) may display unconventional immune signatures of exposure to M. tuberculosis (M.tb). Methods: In a cohort of RSTRs and matched controls with latent TB infection (LTBI), we profiled the functional breadth of M.tb antigen-specific T cell and antibody responses using multi-parameter flow cytometry and systems serology, respectively. Findings: RSTRs and LTBI controls both exhibited IFN-γ independent T-cell and IgG antibody responses to M.tb-specific antigens ESAT-6 and CFP-10. Antigen-specific antibody Fc galactosylation and sialylation were higher among RSTRs. In a combined T-cell and antibody analysis, M.tb lysate-stimulated TNF secretion by T cells correlated positively with levels of purified protein derivative-specific IgG. A multivariate model of the combined data was able to differentiate RSTR and LTBI subjects. Interpretation: IFN-γ independent immune signatures of exposure to M.tb, which are not detected by approved clinical diagnostics, are readily detectable in an occupational cohort uniquely characterized by intense and long-term infection pressure. Further, TNF may mediate a coordinated response between M.tb-specific T-cells and B-cells. Funding: This work was supported by the US National Institutes of Health (R01-AI124348 to Boom, Stein, and Hawn; R01-AI125189 and R01-AI146072 to Seshadri; and 75N93019C00071 to Fortune, Alter, Seshadri, and Boom), the Doris Duke Charitable Foundation (Davies), the Bill & Melinda Gates Foundation (OPP1151836 and OPP1109001 to Hawn; and OPP1151840 to Alter), Mass Life Science Foundation (Fortune), and Good Ventures Fund (Fortune)