Hospital and Physician Capacity Update

Offers an alternative view of healthcare costs by examining trends in hospital capacity and healthcare labor across regions. Outlines how effective management of healthcare capacity would enable affordable quality care that meets patient needs and wants

Inhibition of Sonic hedgehog signaling in vivo results in craniofacial neural crest cell death

Background: Sonic hedgehog (Shh) is well known for its role in patterning tissues, including structures of the head. Haploinsufficiency for SHH in humans results in holoprosencephaly, a syndrome characterized by facial and forebrain abnormalities. Shh null mice have cyclopia and loss of branchial arch structures. It is unclear, however, whether these phenotypes arise solely from the early function of Shh in patterning midline structures, or whether Shh plays other roles in head development. Results: To address the role of Shh after floorplate induction, we inhibited Shh signaling by injecting hybridoma cells that secrete a function-blocking anti-Shh antibody into the chick cranial mesenchyme. The antibody subsequently bound to Shh in the floorplate, notochord, and the pharyngeal endoderm. Perturbation of Shh signaling at this stage resulted in a significant reduction in head size after 1 day, loss of branchial arch structures after 2 days, and embryos with smaller heads after 7 days. Cell death was significantly increased in the neural tube and neural crest after 1 day, and neural crest cell death was not secondary to the loss of neural tube cells. Conclusions: Reduction of Shh signaling after neural tube closure resulted in a transient decrease in neural tube cell proliferation and an extensive increase in cell death in the neural tube and neural crest, which in turn resulted in decreased head size. The phenotypes observed after reduction of Shh are similar to those observed after cranial neural crest ablation. Thus, our results demonstrate a role for Shh in coordinating the proliferation and survival of cells of the neural tube and cranial neural crest

Trends and Variation in End-of-Life Care for Medicare Beneficiaries With Severe Chronic Illness

Provides an updated analysis of regional and hospital variations in end-of-life care for Medicare beneficiaries with chronic illnesses, including percentage of hospital deaths, days in intensive care units, and physician labor per patient

The balance between N-cadherin and E-cadherin orchestrates major neuroectodermal cell fate choices

Numerous cadherin proteins, including N‐cadherin (Ncad), E‐cadherin (Ecad), Cadherin‐11 (Cad11) and Cadherin‐7 (Cad7), are expressed in the developing neural plate as well as in neural crest cells as they delaminate from the newly closed neural tube. To clarify whether these proteins function independently or coordinately during development, we examined their relative expression in the cranial region of chick embryos. The results revealed surprising overlap of Ecad, Ncad and Cad7 in the neural tube, suggesting possible heterotypic interactions. Using a proximity ligation assay and co‐immunoprecipitation to test this hypothesis, we found that Ncad formed heterophilic complexes in the developing neural tube with Ecad. We also determined that modulation of either Ncad or Ecad levels led to reciprocal gain or reduction of the other cadherin protein. Altering levels of the two cadherin proteins affected the early fate specification of ectodermal derivatives, forcing an aberrant choice between neural crest and epidermal cells. Finally, we identified that the availability of β‐catenin plays a critical role in maintaining the balance between Ncad and Ecad in early development since co‐expression of activated β‐catenin rescues the Ncad‐overexpression phenotype. These results suggest that β‐catenin‐mediated balance of Ncad and Ecad proteins is critical for the normal development of the three ectodermal derivatives

Quantitative insertion-site sequencing (QIseq) for high throughput phenotyping of transposon mutants

Genetic screening using random transposon insertions has been a powerful tool for uncovering biology in prokaryotes, where whole-genome saturating screens have been performed in multiple organisms. In eukaryotes, such screens have proven more problematic, in part because of the lack of a sensitive and robust system for identifying transposon insertion sites. We here describe quantitative insertion-site sequencing, or QIseq, which uses custom library preparation and Illumina sequencing technology and is able to identify insertion sites from both the 5' and 3' ends of the transposon, providing an inbuilt level of validation. The approach was developed using piggyBac mutants in the human malaria parasite Plasmodium falciparum but should be applicable to many other eukaryotic genomes. QIseq proved accurate, confirming known sites in >100 mutants, and sensitive, identifying and monitoring sites over a >10,000-fold dynamic range of sequence counts. Applying QIseq to uncloned parasites shortly after transfections revealed multiple insertions in mixed populations and suggests that >4000 independent mutants could be generated from relatively modest scales of transfection, providing a clear pathway to genome-scale screens in P. falciparum QIseq was also used to monitor the growth of pools of previously cloned mutants and reproducibly differentiated between deleterious and neutral mutations in competitive growth. Among the mutants with fitness defects was a mutant with a piggyBac insertion immediately upstream of the kelch protein K13 gene associated with artemisinin resistance, implying mutants in this gene may have competitive fitness costs. QIseq has the potential to enable the scale-up of piggyBac-mediated genetics across multiple eukaryotic systems

A kinesin motor in a force-producing conformation

<p>Abstract</p> <p>Background</p> <p>Kinesin motors hydrolyze ATP to produce force and move along microtubules, converting chemical energy into work by a mechanism that is only poorly understood. Key transitions and intermediate states in the process are still structurally uncharacterized, and remain outstanding questions in the field. Perturbing the motor by introducing point mutations could stabilize transitional or unstable states, providing critical information about these rarer states.</p> <p>Results</p> <p>Here we show that mutation of a single residue in the kinesin-14 Ncd causes the motor to release ADP and hydrolyze ATP faster than wild type, but move more slowly along microtubules in gliding assays, uncoupling nucleotide hydrolysis from force generation. A crystal structure of the motor shows a large rotation of the stalk, a conformation representing a force-producing stroke of Ncd. Three C-terminal residues of Ncd, visible for the first time, interact with the central β-sheet and dock onto the motor core, forming a structure resembling the kinesin-1 neck linker, which has been proposed to be the primary force-generating mechanical element of kinesin-1.</p> <p>Conclusions</p> <p>Force generation by minus-end Ncd involves docking of the C-terminus, which forms a structure resembling the kinesin-1 neck linker. The mechanism by which the plus- and minus-end motors produce force to move to opposite ends of the microtubule appears to involve the same conformational changes, but distinct structural linkers. Unstable ADP binding may destabilize the motor-ADP state, triggering Ncd stalk rotation and C-terminus docking, producing a working stroke of the motor.</p

The other side of surveillance: Monitoring, application, and integration of tuberculosis data to guide and evaluate programme activities in South Africa

Background. The importance of using surveillance data to monitor and evaluate programme activities has been emphasised in international policies for tuberculosis (TB) control.Objectives. A survey was conducted to assess the use of TB surveillance data to monitor and guide TB programme activities in South Africa (SA).Methods. As part of an evaluation of the SA national TB surveillance system, semi-structured interviews were conducted among TB staff at health facilities and offices in three provinces. At each site, all persons involved with TB care, management and surveillance were invited to participate.Results. At least one person (range 1 - 4) was interviewed at 47/54 health facilities (87.0%), 11/13 subdistrict and district TB offices (84.6%), 2/3 provincial TB offices (66.7%), and at the national level (1/1, 100.0%). Of 119 TB staff, 64.7% recognised the purpose of TB surveillance as guiding programme planning, implementation and evaluation. However, only 16.0% reported using data to measure disease burden, 8.4% to monitor trends, and 9.2% to inform resource allocation. The majority reported using TB management tools provided by the national programme, but 44.5% also described using additional tools. Personnel mentioned the need for dedicated surveillance staff, training on recording and reporting, improved computer access, and methods to apply information from surveillance data to the programme.Conclusions. The majority of TB staff understood the purpose of surveillance but did not routinely use data to guide programme planning, implementation and evaluation. Training and supporting TB staff to utilise surveillance data will help improve the TB surveillance system

Tracking the Care of Patients with Severe Chronic Illness - The Dartmouth Atlas of Health Care 2008

In 2001 the Institute of Medicine (IOM) issued Crossing the Quality Chasm, a report that sent a wake-up call to patients, providers, and policy makers about the poor quality of American health care. The IOM argued that one of the central drivers of poor quality has been the unsystematic and fragmentary nature of our health care delivery system. Nowhere are the system’s failings more apparent than in the care of the chronically ill. More than 90 million Americans live with at least one chronic illness, and seven out of ten Americans die from chronic disease. Among the Medicare population, the toll is even greater: about nine out of ten deaths are associated with just nine chronic illnesses, including congestive heart failure, chronic lung disease, cancer, coronary artery disease, renal failure, peripheral vascular disease, diabetes, chronic liver disease, and dementia