Serratia sp. strain FGI 94 was isolated from a fungus garden of the leaf-cutter ant Atta colombica. Analysis of its 4.86-Mbp chromosome will help advance our knowledge of symbiotic interactions and ...plant biomass degradation in this ancient ant-fungus mutualism.
Idiopathic right ventricular outflow tract (RVOT) tachycardia is a well-described example of an adrenergically mediated form of ventricular tachycardia (VT). The mechanism responsible for RVOT VT is ...cyclic adenosine monophosphate-mediated triggered activity. A characteristic and identifying feature of this form of VT is termination in response to a bolus dose of adenosine, which is believed to be related to its antiadrenergic effects. This effect of adenosine on RVOT tachycardia may be mediated on at least 2 sites: (1) the cardiac myocyte, and (2) the presynaptic postganglionic sympathetic nerve fibers. Although continuous intravenous infusion of adenosine increases sympathetic nerve traffic, we have previously demonstrated that a bolus of adenosine results in a biphasic response of muscle sympathetic nerve activity (MSNA). An initial increase in MSNA is immediately followed by profound sympathetic withdrawal. We therefore sought to determine if adenosine's antiarrhythmic effects mediated on RVOT VT were solely related to its direct antiadrenergic effects at the cardiac myocyte, or were also temporally related to its potentially synergistic suppressive effects on MSNA, consistent with a presynaptic postganglionic mechanism of action.
A study shows that ventricular induction studies performed for risk assessment in patients with ischemic cardiomyopathy and nonsustained ventricular tachycardia should include coupling intervals that ...are limited only by refractoriness and not be an arbitrary coupling interval.
Les risques environnementaux et professionnels préoccupent de plus en plus les pays industrialisés soumis, vieillissement des populations aidant, à l'aggravation du fléau des maladies chroniques. Aux ...États-Unis, la responsabilité de ces formes nouvelles d'exposition aux produits toxiques se juge devant les tribunaux. Ces dernières années, la question de savoir à quel moment les entreprises, chimiques ou autres, ont eu connaissance de la nocivité de leurs produits, a mené les jurys à solliciter les historiens. Certains ont mis leur expertise au service de l'industrie dans les procès intentés par les ouvriers ou les consommateurs de tabac, de plomb ou d'amiante. D'autres ont au contraire témoigné au profit des plaignants, à commencer par les auteurs du présent article qui retracent leur expérience dans des affaires liées à l'exposition d'enfants ou d'ouvriers à la silice, au plomb et aux plastiques. Ils analysent la réaction des entreprises mais aussi des autres historiens à leur implication dans ces procès. Ils s'efforcent de déterminer le rôle possible des historiens au prétoire, et comment articuler leur éthos professionnel avec l'argumentaire juridique. /// The risks associated with environmental and occupational exposures are a topic of enormous concern as industrialized nations face the prospects of aging populations and a growing burden of chronic disease. Because of this courts in the United States are being asked to decide who is responsible for new conditions associated with toxic exposures. In recent years historians have been called into courtrooms to explain to juries when information about the dangers of chemicals and other disease-causing agents were known to companies that made or marketed dangerous products. Some have used their expertise to defend industries against lawsuits by workers and consumers in tobacco, lead, asbestosis. Others, such as the authors of this paper, have testified on behalf of workers and consumers who are seeking damages and redress from polluting companies. This paper looks at this recent development through the lens of two historians who have participated in court cases on behalf of children and workers who have come down with diseases associated with exposures to silica, lead, and plastics. Specifically, we explore the response of industries and other historians to our involvement in these cases. We raise the question: what is the proper role of historians in the courtroom and how do we balance our professional and advocacy roles?
We evaluated the efficacy and toxicity of weekly paclitaxel in patients with previously treated advanced urothelial cancer.
Patients with urothelial cancer who had received one prior systemic ...chemotherapy regimen for advanced disease and had evidence of disease progression were eligible for enrollment. Patients received paclitaxel 80 mg/m(2) by 1-hour intravenous infusion weekly. A cycle of therapy consisted of four weekly treatments.
The study enrolled 31 patients. Mean age was 66 years, and 45% of patients had three or more involved metastatic sites. Only 26% of patients had responded to prior chemotherapy. The median number of cycles delivered was three (range, one to eight) at a mean weekly paclitaxel dose of 79 mg/m(2). Three patients achieved a partial response (10%; 95% confidence interval, 0% to 20%). Median time to progression was 2.2 months, and median overall survival time was 7.2 months. Therapy was well tolerated with minimal hematologic toxicity. Grade 3 nonhematologic toxicities were also uncommon.
Although the overall response rate to weekly paclitaxel in patients with previously treated advanced urothelial cancer was modest, the chemotherapy-refractory nature of the study population should be considered.
Most microbes in the biosphere remain uncultured and unknown. Whole genome shotgun (WGS) sequencing of environmental DNA (metagenomics) allows glimpses into genetic and metabolic potentials of ...natural microbial communities. However, in communities of high complexity metagenomics fail to link specific microbes to specific ecological functions. To overcome this limitation, we selectively targeted populations involved in oxidizing single-carbon (C{sub 1}) compounds in Lake Washington (Seattle, USA) by labeling their DNA via stable isotope probing (SIP), followed by WGS sequencing. Metagenome analysis demonstrated specific sequence enrichments in response to different C{sub 1} substrates, highlighting ecological roles of individual phylotypes. We further demonstrated the utility of our approach by extracting a nearly complete genome of a novel methylotroph Methylotenera mobilis, reconstructing its metabolism and conducting genome-wide analyses. This approach allowing high-resolution genomic analysis of ecologically relevant species has the potential to be applied to a wide variety of ecosystems.
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