48 research outputs found
Dynamics, scaling behavior, and control of nuclear wrinkling
The cell nucleus is enveloped by a complex membrane, whose wrinkling has been
implicated in disease and cellular aging. The biophysical dynamics and spectral
evolution of nuclear wrinkling during multicellular development remain poorly
understood due to a lack of direct quantitative measurements. Here, we combine
live-imaging experiments, theory, and simulations to characterize the onset and
dynamics of nuclear wrinkling during egg development in the fruit fly,
Drosophila melanogaster, when nurse cell nuclei increase in size and display
stereotypical wrinkling behavior. A spectral analysis of three-dimensional
high-resolution data from several hundred nuclei reveals a robust asymptotic
power-law scaling of angular fluctuations consistent with renormalization and
scaling predictions from a nonlinear elastic shell model. We further
demonstrate that nuclear wrinkling can be reversed through osmotic shock and
suppressed by microtubule disruption, providing tunable physical and biological
control parameters for probing mechanical properties of the nuclear envelope.
Our findings advance the biophysical understanding of nuclear membrane
fluctuations during early multicellular development.Comment: Main text: 10 pages, 3 figures. SI: 19 pages, 10 figures, 1 tabl
Surviving sepsis: going beyond the guidelines
The Surviving Sepsis Campaign is a global effort to improve the care of patients with severe sepsis and septic shock. The first Surviving Sepsis Campaign Guidelines were published in 2004 with an updated version published in 2008. These guidelines have been endorsed by many professional organizations throughout the world and come regarded as the standard of care for the management of patients with severe sepsis. Unfortunately, most of the recommendations of these guidelines are not evidence-based. Furthermore, the major components of the 6-hour bundle are based on a single-center study whose validity has been recently under increasing scrutiny. This paper reviews the validity of the Surviving Sepsis Campaign 6-hour bundle and provides a more evidence-based approach to the initial resuscitation of patients with severe sepsis
Recommendations for active correction of hypernatremia in volume-resuscitated shock or sepsis patients should be taken with a grain of salt: A systematic review
Background: Healthcare-acquired hypernatremia (serum sodium >145 mEq/dL) is common among critically ill and other
hospitalized patients and is usually treated with hypotonic fluid and/or diuretics to correct a “free water deficit.� However,
many hypernatremic patients are eu- or hypervolemic, and an evolving body of literature emphasizes the importance of
rapidly returning critically ill patients to a neutral fluid balance after resuscitation.
Objective: We searched for any randomized- or observational-controlled studies evaluating the impact of active interventions
intended to correct hypernatremia to eunatremia on any outcome in volume-resuscitated patients with shock and/or sepsis.
Data sources: We performed a systematic literature search with studies identified by searching MEDLINE, Embase,
Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, ClinicalTrials.gov, IndexCatalogue
of the Library of the Surgeon General’s Office, DARE (Database of Reviews of Effects), and CINAHL and scanning
reference lists of relevant articles with abstracts published in English.
Data synthesis: We found no randomized- or observational-controlled trials measuring the impact of active correction of
hypernatremia on any outcome in resuscitated patients.
Conclusion: Recommendations for active correction of hypernatremia in resuscitated patients with sepsis or shock are
unsupported by clinical research acceptable by modern evidence standards.ECU Open Access Publishing Support Fun