Proc Natl Acad Sci U S A
November 2010
We estimate the potential reductions in methane and carbon dioxide emissions from several livestock and pasture management options in the mixed and rangeland-based production systems in the tropics. The impacts of adoption of improved pastures, intensifying ruminant diets, changes in land-use practices, and changing breeds of large ruminants on the production of methane and carbon dioxide are calculated for two levels of adoption: complete adoption, to estimate the upper limit to reductions in these greenhouse gases (GHGs), and optimistic but plausible adoption rates taken from the literature, where these exist. Results are expressed both in GHG per ton of livestock product and in Gt CO(2)-eq.
View Article and Find Full Text PDFDuring the cell cycle, gap junction communication, morphology and distribution of connexin43 (Cx43)-containing structures change dramatically. As cells round up in mitosis, Cx43 labeling is mostly intracellular and intercellular coupling is reduced. We investigated Cx43 distributions during mitosis both in endogenous and exogenous expressing cells using optical pulse-chase labeling, correlated light and electron microscopy, immunocytochemistry and biochemical analysis.
View Article and Find Full Text PDFPhilos Trans R Soc Lond B Biol Sci
September 2010
The livestock sector globally is highly dynamic. In developing countries, it is evolving in response to rapidly increasing demand for livestock products. In developed countries, demand for livestock products is stagnating, while many production systems are increasing their efficiency and environmental sustainability.
View Article and Find Full Text PDFPrevious work showed that about 85% of stress-induced mutations associated with DNA double-strand break repair in carbon-starved Escherichia coli result from error-prone DNA polymerase IV (Pol IV) (DinB) and that the mutagenesis is controlled by the RpoS stress response, which upregulates dinB. We report that the remaining mutagenesis requires high-fidelity Pol II, and that this component also requires RpoS. The results identify a second DNA polymerase contributing to stress-induced mutagenesis and show that RpoS promotes mutagenesis by more than the simple upregulation of dinB.
View Article and Find Full Text PDFEscherichia coli has five DNA polymerases, one of which, the low-fidelity Pol IV or DinB, is required for stress-induced mutagenesis in the well-studied Lac frameshift-reversion assay. Although normally present at approximately 200 molecules per cell, Pol IV is recruited to acts of DNA double-strand-break repair, and causes mutagenesis, only when at least two cellular stress responses are activated: the SOS DNA-damage response, which upregulates DinB approximately 10-fold, and the RpoS-controlled general-stress response, which upregulates Pol IV about 2-fold. DNA Pol III was also implicated but its role in mutagenesis was unclear.
View Article and Find Full Text PDFPathways of mutagenesis are induced in microbes under adverse conditions controlled by stress responses. Control of mutagenesis by stress responses may accelerate evolution specifically when cells are maladapted to their environments, i.e.
View Article and Find Full Text PDFLarge granular lymphocyte leukemia (T-LGL) is an indolent T lymphoproliferative disorder that was difficult to diagnose with certainty until clonality testing of the T cell receptor gene became routinely available. We studied the natural history and response to treatment in 25 consecutive patients with T-LGL diagnosed between 2004 and 2008 in which the diagnosis was confirmed by molecular analysis, to define an effective treatment algorithm. The median age at diagnosis was 61 years (range 27-78), with a male to female ratio of 1:1.
View Article and Find Full Text PDFWhite blood cell infiltration across an activated brain endothelium contributes to neurologic disease, including cerebral ischemia and multiple sclerosis. Identifying mechanisms of cerebrovascular activation is therefore critical to our understanding of brain disease. Platelet accumulation in microvessels of ischemic mouse brain was associated with endothelial activation in vivo.
View Article and Find Full Text PDFFarmers in mixed crop-livestock systems produce about half of the world's food. In small holdings around the world, livestock are reared mostly on grass, browse, and nonfood biomass from maize, millet, rice, and sorghum crops and in their turn supply manure and traction for future crops. Animals act as insurance against hard times and supply farmers with a source of regular income from sales of milk, eggs, and other products.
View Article and Find Full Text PDFStimuli-responsive gate mechanisms offer potential for the controlled passage of payload molecules from a porous carrier vehicle on-demand. We describe a method for the enzyme-mediated release of macromolecular guest molecules from inorganic silica particles coated with a bioactive peptide shell, synthesized precisely by Fmoc chemistry. Specific enzymatic hydrolysis of the peptide shell removes the bulky peptide-terminated Fmoc groups, permitting the selective release of previously entrapped guest molecules.
View Article and Find Full Text PDFThe coagulation system undergoes significant change during pregnancy. The clinician caring for the parturient must understand these changes, particularly when the parturient has a pre-existing haematological condition. Because many haematological conditions are rare, there often is limited information to guide the obstetric and anaesthetic management of these parturients.
View Article and Find Full Text PDFPurpose: Little is known concerning the onset, duration, and magnitude of direct therapeutic effects of anti-vascular endothelial growth factor (VEGF) therapies. Such knowledge would help guide the rational development of targeted therapeutics from bench to bedside and optimize use of imaging technologies that quantify tumor function in early-phase clinical trials.
Experimental Design: Preclinical studies were done using ex vivo microcomputed tomography and in vivo ultrasound imaging to characterize tumor vasculature in a human HM-7 colorectal xenograft model treated with the anti-VEGF antibody G6-31.
Inflammation is a classical host defence response to infection and injury that has many beneficial effects. However, inappropriate (in time, place and magnitude) inflammation is increasingly implicated in diverse disease states, now including cancer, diabetes, obesity, atherosclerosis, heart disease and, most relevant here, CNS disease. A growing literature shows strong correlations between inflammatory status and the risk of cerebral ischaemia (CI, most commonly stroke), as well as with outcome from an ischaemic event.
View Article and Find Full Text PDFStroke is the major cause of disability in the Western world and is the third greatest cause of death, but there are no widely effective treatments to prevent the devastating effects of stroke. Extensive and growing evidence implicates inflammatory and immune processes in the occurrence of stroke and particularly in the subsequent injury. Several inflammatory mediators have been identified in the pathogenesis of stroke including specific cytokines, adhesion molecules, matrix metalloproteinases, and eicosanoids.
View Article and Find Full Text PDFDiuretic use and overactive bladder syndrome are common in older adults. However, the relationship between the two has not been well studied. Data were collected by self-administered questionnaires including the Urge Urinary Distress Inventory (Urge-UDI) and the Urge Incontinence Impact Questionnaire (Urge-IIQ), and by outpatient chart abstraction.
View Article and Find Full Text PDFCongenital hyperinsulinism is a condition of dysregulated insulin secretion often caused by inactivating mutations of the ATP-sensitive K+ (KATP) channel in the pancreatic beta cell. Though most disease-causing mutations of the 2 genes encoding KATP subunits, ABCC8 (SUR1) and KCNJ11 (Kir6.2), are recessively inherited, some cases of dominantly inherited inactivating mutations have been reported.
View Article and Find Full Text PDFUnderstanding models of multidisciplinary collaborations in child welfare has become essential for policy development, program success, and improving outcomes for children in foster care. The authors present the state of Maryland's Guardianship Assistance Project (GAP) as a model of multidisciplinary collaboration in child welfare and describe the training process that supported the development of the model. Key components for effective collaborative practice, lessons learned, and recommendations from the GAP collaboration are presented.
View Article and Find Full Text PDFWe report on enzyme-responsive hydrogel particles for the controlled release of proteins. Amino-functionalised poly(ethylene glycol acrylamide) (PEGA) hydrogel particles were functionalised with peptide actuators that cause charge-induced swelling and payload release when triggered enzymatically. Peptide-based actuators were designed to match the specificity of the target enzyme, while also matching the charge properties of the to-be released protein payload, thereby uniquely allowing for tuneable release profiles.
View Article and Find Full Text PDFPhosphorylation at unspecified sites is known to regulate the life cycle (assembly, gating, and turnover) of the gap junction protein, Cx43. In this paper, we show that Cx43 is phosphorylated on S365 in cultured cells and heart tissue. Nuclear magnetic resonance structural studies of the C-terminal region of Cx43 with an S365D mutation indicate that it forms a different stable conformation than unphosphorylated wild-type Cx43.
View Article and Find Full Text PDFObjective: To investigate the specificity of the 'jump-to-conclusions' (JTC) bias in delusions.
Methods: Thirty-seven psychotic patients were divided into two separate groupings: (1) deluded versus non-deluded individuals and (2) individuals with and without a diagnosis of schizophrenia. Groups were compared on three reasoning tasks ('Beads' task, Wason's 2-4-6 task, and Wason's selection task).
Matrix metalloproteinases (MMPs) are endopeptidases known to mediate acute neuronal injury, but it is unclear whether these proteases are induced by the primary insult or by inflammation associated with injury. We have reported recently that interleukin-1 (IL-1) induces neurotoxicity by an astrocyte-dependent mechanism. The aim of the present study was to test the hypothesis that MMPs mediate IL-1 neurotoxicity in rat, glial-neuronal cocultures.
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