Ultrafast multi-cycle terahertz measurements of the electrical conductivity in strongly excited solids.

Key insights in materials at extreme temperatures and pressures can be gained by accurate measurements that determine the electrical conductivity. Free-electron laser pulses can ionize and excite matter out of equilibrium on femtosecond time scales, modifying the electronic and ionic structures and enhancing electronic scattering properties. The transient evolution of the conductivity manifests the energy coupling from high temperature electrons to low temperature ions. Here we combine accelerator-based, high-brightness multi-cycle terahertz radiation with a single-shot electro-optic sampling technique to probe the evolution of DC electrical conductivity using terahertz transmission measurements on sub-picosecond time scales with a multi-undulator free electron laser. Our results allow the direct determination of the electron-electron and electron-ion scattering frequencies that are the major contributors of the electrical resistivity.

Response to angiotensin blockade with irbesartan in a patient with metastatic colorectal cancer.

BACKGROUND: A patient suffering from metastatic colorectal cancer, treatment-related toxicity and resistance to standard chemotherapy and radiation was assessed as part of a personalized oncogenomics initiative to derive potential alternative therapeutic strategies. PATIENTS AND METHODS: Whole-genome and transcriptome sequencing was used to interrogate a metastatic tumor refractory to standard treatments of a patient with mismatch repair-deficient metastatic colorectal cancer. RESULTS: Integrative genomic analysis indicated overexpression of the AP-1 transcriptional complex suggesting experimental therapeutic rationales, including blockade of the renin-angiotensin system. This led to the repurposing of the angiotensin II receptor antagonist, irbesartan, as an anticancer therapy, resulting in the patient experiencing a dramatic and durable response. CONCLUSIONS: This case highlights the utility of comprehensive integrative genomic profiling and bioinformatics analysis to provide hypothetical rationales for personalized treatment options.

External validation of the In-hospital Mortality for PulmonAry embolism using Claims daTa (IMPACT) multivariable prediction rule.

OBJECTIVE: To validate the In-hospital Mortality for PulmonAry embolism using Claims daTa (IMPACT) multivariable prediction rule using admission claims data. STUDY DESIGN: Retrospective claims database analysis. METHODS: This analysis was performed using Humana admission claims data from January 2007 to March 2014. We included adult patients admitted for their first PE during this period (International Classification of Diseases, ninth edition, Clinical Modification code of 415.1x in in the primary position or secondary position when accompanied by a primary code for a PE complication). The IMPACT rule, consisting of age plus 11 comorbidities, was used to estimate patients' probability of in-hospital mortality and classify risk. Low risk was defined as in-hospital mortality ≤ 1.5%. IMPACT was evaluated by evaluating prognostic test characteristic values and 95% confidence intervals (CIs). RESULTS: A total of 23,858 patients admitted for PE were included, and 3.3% died in-hospital. The IMPACT prediction rule classified 2371 (9.9%) as low-risk; with a sensitivity of 97.6%, 95% CI: 96.1-98.5, specificity of 10.2%, 95% CI: 9.8-10.6, negative and positive predictive values of 99.2% (95% CI: 98.7-99.5) and 3.5% (95% CI: 3.3-3.8) and c-statistic of 0.70, 95% CI: 0.0.68-0.72, for in-hospital mortality. IMPACT classified 42.7% of patients < 65 years old as low-risk; with a sensitivity, specificity and c-statistic of 85.0%, 95% CI: 77.4-90.5, 43.3%, 95% CI: 42.0-44.7 and 0.74, 95% CI: 0.69-0.78, respectively. CONCLUSION: The IMPACT prediction rule was valid when implemented in a database consisting largely of Medicare claims. Following further external validation and direct comparison to commonly used clinical prediction rules, IMPACT may become a valuable tool for payers and hospitals wishing to retrospectively assess whether their PE patients are being kept hospitalized for the optimal period of time.

Incidence of hospital readmission in patients diagnosed with DVT and PE: clinical burden of recurrent events.

BACKGROUND: Venous thromboembolism (VTE), which comprises deep-vein thrombosis (DVT) and pulmonary embolism (PE), is associated with significant morbidity and mortality and represents a considerable economic burden to the US healthcare system. Although it is well established that patients with an initial VTE are at increased risk for recurrent VTE, limited data exist on the clinical burden of a secondary DVT or PE event. The objective of this retrospective observational study was to conduct an epidemiologic evaluation, from a hospital perspective, of patients with an initial DVT or PE who experienced a recurrent event postdischarge requiring hospital readmission. METHODS: Hospital claims containing DVT or PE as a primary diagnosis for hospitalisation during the period October 2009 to April 2013 were identified by retrospective analysis using the MarketScan database. The time to hospital readmission for DVT or PE was assessed using the MarketScan Treatment Pathways tool. RESULTS: Of 214,901 patient admissions identified with a diagnosis of DVT or PE at hospital admission, approximately 4% were subsequently readmitted to the hospital with a diagnosis of PE (8217) or DVT (9138). Of all readmitted patients with a diagnosis of DVT on initial admission, 66% were rehospitalised with a diagnosis of DVT, and 34% were rehospitalised with a diagnosis of PE. Of all readmitted patients with a diagnosis of PE on initial admission, 63% were rehospitalised with a diagnosis of PE and 37% with a diagnosis of DVT. Of all hospital readmissions with a diagnosis of PE or DVT, 62% and 58% occurred within the first 30 days following an initial PE or DVT event, respectively. CONCLUSIONS: The burden of DVT or PE is large, not only because of the initial hospitalisation event but also because of the high number of hospital readmissions, more than half of which occur within 30 days.

Prasugrel vs. clopidogrel in acute coronary syndrome patients treated with prasugrel.

WHAT IS KNOWN AND OBJECTIVE: Current guidelines recommend a combination of clopidogrel and aspirin for management of patients who have experienced an acute coronary syndrome (ACS). Additional antiplatelet agents have been recently approved. Few comparative effectiveness studies are available for these new agents. Accordingly, we evaluated effect on time to hospital admission and resource utilization (number of hospitalizations, ER visits and outpatient visits) of prasugrel vs. clopidogrel in prasugrel-treated patients as assessed in a matched cohort. METHODS: Based on the Truven Health Analytics MarketScan database from 01 January 2009 through 31 July 2012, a retrospective prasugrel-clopidogrel matched cohort was created. Inferences for average treatment effect over 1 and 12 months on time to hospitalization and resource utilization were performed by (i) frequentist Kaplan-Meier estimation with a Cox proportional hazard model and Lin's cost history method for censored resource utilization outcomes and (ii) Bayesian discrete-time hazard and negative binomial models. RESULTS AND DISCUSSION: The 10,963 matched pairs were well balanced on baseline characteristics. Frequentist analyses of time to hospital admission over 365 days and mean all-cause resource utilization over 30 and 365 days showed no statistical differences between prasugrel and clopidogrel (P-values > 0·05). Based on Bayesian analysis of time to admission over 12 months, there was positive evidence of equivalence (0·987 probability of equivalence at a 10% equivalence margin and a Bayes factor of 0·611). Although the frequentist analyses for number of all-cause hospitalizations showed a lack of a significant difference at Months 1 and 12, the Bayesian data analysis showed positive evidence of superiority of clopidogrel at Month 1 (Bayes factor: 5·369); however, at Month 12, there was little evidence of superiority of one treatment over the other (Bayes factor: 0·422). WHAT IS NEW AND CONCLUSION: Using frequentist and Bayesian data analyses, in prasugrel-treated patients, clopidogrel was equivalent to prasugrel for time to hospital admission over 12 months and there was positive evidence that it was superior to prasugrel for number of hospitalizations over the first month of treatment.

Prior myocardial infarction and presence of upper gastrointestinal conditions among patients with venous thromboembolism: prevalence, associated comorbidities and burden.

WHAT IS KNOWN AND OBJECTIVES: Venous thromboembolism (VTE), comprising deep vein thrombosis (DVT) and pulmonary embolism (PE), is a serious, life-threatening condition that often complicates treatment of individuals who are already ill and increases in risk with age. The comorbidity burden of VTE can complicate treatment; therefore, treatment should be influenced by the presence of comorbidities (Kearon 2012). The prevalence of common conditions in the VTE population is, therefore, an important subject of research. Prevalence of two common comorbid burdens, prior myocardial infarction (MI) and upper gastrointestinal (GI) conditions, was studied among survey respondents who reported DVT or PE. METHODS: Responses to the 2010 wave of the National Health and Wellness Survey (NHWS), a self-administered, internet-based questionnaire from a nationwide, demographically representative sample of adults, were evaluated. RESULTS AND DISCUSSION: Among the 814 participants reporting a history of VTE, 9·7% (n = 60) of the DVT subpopulation and 13·2% (n = 39) of the PE subpopulation also reported prior MI. In respondents with prior MI, cardiovascular, urological, and pain comorbidities were each reported as additional comorbidities by at least two thirds of respondents in both the PE and DVT subpopulations, with cardiovascular and urological conditions reported significantly (P < 0·05) more often than among respondents with no prior MI. Among the respondents reporting VTE, 48·9% (n = 302) of the subpopulation reporting DVT and 52·2% (n = 154) of those reporting PE also reported upper GI comorbidities. Cardiovascular and pain conditions in the respondents reporting upper GI comorbidities were each reported by more than three quarters of VTE patients in both the DVT and PE subpopulations and were significantly more common (P < 0·05) than among their counterparts without upper GI comorbidities. WHAT IS NEW AND CONCLUSION: The results of the NHWS indicate that VTE patients who have either of two common comorbid burdens, prior MI and concomitant upper GI conditions, also showed high levels of additional, concurrent comorbidities and generally poor health status. Clinicians must be aware of the total comorbidity profile of their patients who have experienced VTE in order to best manage them and prescribe appropriate therapy.

Risk factors associated with myocardial infarction in venous thromboembolism patients.

BACKGROUND: Although risk factors for MI have been described in the general population, there is a lack of data on the assessment of risk factors associated with MI in venous thromboembolism (VTE) patients. OBJECTIVE: The purpose of this study was to identify risk factors associated with MI in VTE patients. PATIENTS AND METHODS: Health insurance claims between January 2004 and September 2008 from the Ingenix IMPACT database were analyzed. Patients aged ≥18 years were identified as of the date of their first VTE diagnosis with ≥1 year of continuous insurance coverage before the index VTE. The risk of MI for VTE patients with 1, 2, and ≥3 major risk factors as identified by published guidelines was calculated. Multivariate Cox proportional hazard models were conducted to identify the most predictive risk factors associated with MI. RESULTS: A total of 177,885 VTE patients were identified; 4412 (2.5%) developed an MI during a mean follow-up period of 1.3 years. Previous MI, age (≥65 years), and coronary artery disease were the most predictive risk factors of MI with adjusted hazard ratios (HRs; 95% CI) of 5.47 (5.01-5.97), 1.78 (1.66-1.91), and 1.60 (1.48-1.74), respectively. Adjusted HRs (95% CI) for VTE patients with 1, 2, and ≥3 major risk factors relative to no major risk factor were 2.34 (1.94-2.81), 3.21 (2.67-3.85), and 6.93 (5.85-8.22), respectively. LIMITATIONS: These included possible inaccuracies or omissions in diagnoses, classification bias such as the identification of false-positive MI events, and the likely undercoding of some risk factors such as social issues. CONCLUSIONS: Traditional major cardiovascular risk factors are also predictive of MI in VTE patients. Having multiple major risk factors significantly increases the probability of developing MI events in VTE patients.

In-hospital risk of venous thromboembolism and bleeding and associated costs for patients undergoing total hip or knee arthroplasty.

OBJECTIVE: Benefits of anti-coagulation for venous thromboembolism (VTE) prevention in total hip and knee arthroplasty (THA/TKA) may be offset by increased risk of bleeding. The aim was to assess in-hospital risk of VTE and bleeding after THA/TKA and quantify any increased costs. METHODS: Healthcare claims from the Premier Perspective(TM) Comparative Hospital Database (January 2000-September 2008) were selected for subjects ≥ 18 years with ≥ 1 diagnosis code for THA/TKA. VTE was defined as ≥ 1 code for deep vein thrombosis or pulmonary embolism. Bleeding was classified as major/non-major. Incremental in-hospital costs associated with VTE and bleeding were calculated as cost differences between inpatients with VTE or bleeding matched 1:1 with inpatients without VTE or bleeding. RESULTS: A total of 820,197 inpatient stays were identified: 8042 had a VTE event and 7401 a bleeding event (2740 major bleeding). The risks of VTE, any bleeding, and major bleeding were 0.98, 0.90, and 0.33/100 inpatient stays, respectively. Mean incremental in-hospital costs per inpatient were $2663 for VTE, $2028 for bleeding, and $3198 for major bleeding. LIMITATIONS: These included possible inaccuracies or omissions in procedures, diagnoses, or costs of claims data; no information on the amount of blood transfused or decreases in the hemoglobin level to evaluate bleeding event severity; and potential biases due to the observational design of the study. CONCLUSIONS: In-hospital risk and incremental all-cause costs with THA/TKA were higher for VTE than for bleeding. Despite higher costs, major bleeding occurred less frequently than VTE, suggesting a favorable benefit/risk profile for VTE prophylaxis in THA/TKA.

High performance gel imaging with a commercial single lens reflex camera.

A high performance gel imaging system was constructed using a digital single lens reflex camera with epi-illumination to image 19 × 23 cm agarose gels with up to 10,000 DNA bands each. It was found to give equivalent performance to a laser scanner in this high throughput DNA fingerprinting application using the fluorophore SYBR Green(®). The specificity and sensitivity of the imager and scanner were within 1% using the same band identification software. Low and high cost color filters were also compared and it was found that with care, good results could be obtained with inexpensive dyed acrylic filters in combination with more costly dielectric interference filters, but that very poor combinations were also possible. Methods for determining resolution, dynamic range, and optical efficiency for imagers are also proposed to facilitate comparison between systems.

Genome variation in Cryptococcus gattii, an emerging pathogen of immunocompetent hosts.

Cryptococcus gattii recently emerged as the causative agent of cryptococcosis in healthy individuals in western North America, despite previous characterization of the fungus as a pathogen in tropical or subtropical regions. As a foundation to study the genetics of virulence in this pathogen, we sequenced the genomes of a strain (WM276) representing the predominant global molecular type (VGI) and a clinical strain (R265) of the major genotype (VGIIa) causing disease in North America. We compared these C. gattii genomes with each other and with the genomes of representative strains of the two varieties of Cryptococcus neoformans that generally cause disease in immunocompromised people. Our comparisons included chromosome alignments, analysis of gene content and gene family evolution, and comparative genome hybridization (CGH). These studies revealed that the genomes of the two representative C. gattii strains (genotypes VGI and VGIIa) are colinear for the majority of chromosomes, with some minor rearrangements. However, multiortholog phylogenetic analysis and an evaluation of gene/sequence conservation support the existence of speciation within the C. gattii complex. More extensive chromosome rearrangements were observed upon comparison of the C. gattii and the C. neoformans genomes. Finally, CGH revealed considerable variation in clinical and environmental isolates as well as changes in chromosome copy numbers in C. gattii isolates displaying fluconazole heteroresistance.

Economic benefit of a 1-day reduction in hospital stay for community-acquired pneumonia (CAP).

OBJECTIVE: As a component of healthcare reform, payers, hospital administrators, and physicians are looking for ways to reduce hospital expenditures and improve efficiency. The economic benefit of a reduced hospital stay must be weighed against the cost of the treatment or process necessary to achieve the reduced length of stay (LOS). The objective of this paper was to estimate the potential economic benefit of a reduction in inpatient hospital LOS for a common type of admission, community acquired pneumonia (CAP). RESEARCH DESIGN AND METHODS: Data for this study were from the CAP hospital admissions selected from the 2006 Healthcare Cost and Utilization Project (HCUP) National Inpatient Sample (NIS). Potential savings associated with a 1 day reduction in CAP LOS were estimated using three methods: (1) average cost, (2) weighted-average incremental cost of an additional day, and (3) weighted-average predicted mean costs from regression models which were used to estimate incremental cost adjusting for hospitalization characteristics. MAIN OUTCOME MEASURES: Cost per day of CAP hospitalization. RESULTS: A total of 1,471,295 CAP admissions qualified for the analysis. The cost for each day of reduction in LOS in 2009 US dollars was $2273, $2373, and $2319 for the three methods: simple average, incremental, and regression, respectively. Subgroup analysis and regression analysis indicated higher costs were identified: in patients who died in the hospital, had hospital stays in the Northeast or West, and in large hospitals. Longer CAP hospitalizations had a higher cost per additional day. Limitations include those typically associated with the use of administrative claims (e.g., lack of clinical detail, issues related to diagnosis coding). CONCLUSIONS: Eliminating a day during the course of a CAP admission is potentially worth $2273-2373 in economic benefits (2009 dollars). As we strive for greater efficiency in healthcare delivery, changes in processes and/or improved diagnostics or treatments may potentially achieve a reduction in the length of stay. The cost of such changes or improvements must be weighed against the economic benefit of a shorter hospitalization.

Estimating the economic impact of a half-day reduction in length of hospital stay among patients with community-acquired pneumonia in the US.

BACKGROUND: A recent study suggested that levofloxacin significantly reduces the hospital length of stay (LOS), by 0.5 days (p = 0.02), relative to moxifloxacin in patients with community-acquired pneumonia (CAP). The current analysis evaluated the potential economic impact of this half-day reduction in LOS. METHODS: A cost model was developed to estimate the impact of a half-day reduction in LOS for CAP hospitalizations in the US. CAP incidence, hospitalization rate, and costs were obtained from published studies in PubMed and from publicly available government sources. The average daily cost of hospitalization was estimated for fixed costs, which comprise 59% of total inpatient costs. Costs from prior years were inflated to 2007 US dollars using the consumer price index. A range of cost savings, calculated using inpatient CAP costs from several studies, was extrapolated to the US CAP population. RESULTS: Using the Centers for Disease Control National Hospital Discharge estimate of 5.3 days LOS for CAP, and an average cost (2007 $US) of $13,009 per CAP hospitalization, a daily fixed cost of $1448 was estimated. The resultant half-day reduction in costs associated with LOS was $724/hospitalization (range $457 to $846/hospitalization). When fixed and variable costs were considered, the estimated savings were $1227.27/episode. The incidence of CAP was estimated to be 1.9% (5.7 million cases/year based on current population census), and the estimated rate of CAP hospitalization was 19.6% (1.1 million annual hospitalizations). At $13,009/CAP-related hospitalization, total fixed inpatient costs of $8.6 billion annually were projected. The half-day reduction in LOS would therefore generate potential annual savings of approximately $813 million (range $513 million to $950 million). When total costs (fixed plus variable) were estimated, the mean savings for a half-day reduction would be approximately $1227/episode (range of $775 to $1434) or $1.37 billion annually in the US CAP population (range of $871 million to $1.6 billion). Limitations include the use of a single study for the estimation of fixed costs but a diversity of sources used for estimates of other variables, and lack of data with respect to the effects on costs of diagnostic-related groups, discounted contracts, and capitated payments. CONCLUSIONS: A relatively small decrease in LOS in CAP can have a substantial cost impact, with estimated savings of $457 to $846 per episode or $500-$900 million annually. Additional evaluation is warranted for interpreting these cost-savings in the context of current antibiotic prescribing patterns.

Medical resource utilization among community-acquired pneumonia patients initially treated with levofloxacin 750 mg daily versus ceftriaxone 1000 mg plus azithromycin 500 mg daily: a US-based study.

OBJECTIVE: The 2007 American Thoracic Society/Infectious Diseases Society of America (ATS/IDSA) guidelines recommend that community-acquired pneumonia (CAP) patients admitted to hospital wards initially receive respiratory fluoroquinolone monotherapy or beta-lactam plus macrolide combination therapy. There is little evidence as to which regimen is preferred, or if differences in medical resource utilization exist between therapies. Thus, the authors compared length of hospital stay (LOS) and length of intravenous antibiotic therapy (LOIV) for patients who received initial levofloxacin 750 mg daily versus ceftriaxone 1000 mg plus azithromycin 500 mg daily ('combination therapy'). RESEARCH DESIGN AND METHODS: Adult hospital CAP cases from January 2005 to December 2007 were identified by principal discharge diagnosis code. Patients with a chest infiltrate and medical notes indicative of CAP were included. Direct intensive care unit admits and healthcare-associated cases were excluded. A propensity score technique was used to balance characteristics associated with initial antimicrobial therapy using multivariable regression to derive the scores. Propensity score categories, defined as propensity score quintiles, rather than propensity scores themselves, were used in the least squares regression model to assess the impact of LOS and LOIV. RESULTS: A total of 495 patients from six hospitals met study criteria. Of these, 313 (63%) received levofloxacin and 182 (37%) received combination therapy. Groups were similar with respect to age, sex, most comorbidities, presenting signs and symptoms, and Pneumonia Severity Index (PSI) risk class. Patients on combination therapy were more likely to have heart failure and receive pre-admission antibiotics. Adjusted least squares mean (+/-SE) LOS and LOIV were shorter with levofloxacin versus combination therapy: LOS, 4.6 +/- 0.17 vs. 5.4 +/- 0.22 days, p < 0.01; and LOIV, 3.6 +/- 0.17 vs. 4.8 +/- 0.21 days, p < 0.01. Results for PSI risk class III or IV patients were: LOS, 5.0 +/- 0.30 vs. 5.9 +/- 0.37 days, p = 0.07; and LOIV, 3.7 +/- 0.33 vs. 5.2 +/- 0.39 days, p < 0.01. Due to the retrospective study design, limited sample size, and scope (single health-network), the authors encourage replication of this study in other data sources. CONCLUSIONS: Given the LOS and LOIV reductions of 0.8 and 1.2 days, respectively, utilization of levofloxacin 750 mg daily for CAP patients admitted to the medical floor has the potential to result in substantial cost savings for US hospitals.

Demonstration of the density dependence of x-ray flux in a laser-driven hohlraum.

Experiments have been conducted using laser-driven cylindrical hohlraums whose walls are machined from Ta2O5 foams of 100 mg/cc and 4 g/cc densities. Measurements of the radiation temperature demonstrate that the lower density walls produce higher radiation temperatures than the high density walls. This is the first experimental demonstration of the prediction that this would occur [M. D. Rosen and J. H. Hammer, Phys. Rev. E 72, 056403 (2005)10.1103/PhysRevE.72.056403]. For high density walls, the radiation front propagates subsonically, and part of the absorbed energy is wasted by the flow kinetic energy. For the lower wall density, the front velocity is supersonic and can devote almost all of the absorbed energy to heating the wall.

A 2.5-Mb contig constructed from Angus, Longhorn and horned Hereford DNA spanning the polled interval on bovine chromosome 1.

The polled locus has been mapped by genetic linkage analysis to the proximal region of bovine chromosome 1. As an intermediate step in our efforts to identify the polled locus and the underlying causative mutation for the polled phenotype, we have constructed a BAC-based physical map of the interval containing the polled locus. Clones containing genes and markers in the critical interval were isolated from the TAMBT (constructed from Angus and Longhorn genomic DNA) and CHORI-240 (constructed from horned Hereford genomic DNA) BAC libraries and ordered based on fingerprinting and the presence or absence of 80 STS markers. A single contig spanning 2.5 Mb was assembled. Comparison of the physical order of STSs to the corresponding region of human chromosome 21 revealed the same order of genes within the polled critical interval. This contig of overlapping BAC clones from horned and polled breeds is a useful resource for SNP discovery and characterization of positional candidate genes.

The genome of black cottonwood, Populus trichocarpa (Torr. & Gray).

We report the draft genome of the black cottonwood tree, Populus trichocarpa. Integration of shotgun sequence assembly with genetic mapping enabled chromosome-scale reconstruction of the genome. More than 45,000 putative protein-coding genes were identified. Analysis of the assembled genome revealed a whole-genome duplication event; about 8000 pairs of duplicated genes from that event survived in the Populus genome. A second, older duplication event is indistinguishably coincident with the divergence of the Populus and Arabidopsis lineages. Nucleotide substitution, tandem gene duplication, and gross chromosomal rearrangement appear to proceed substantially more slowly in Populus than in Arabidopsis. Populus has more protein-coding genes than Arabidopsis, ranging on average from 1.4 to 1.6 putative Populus homologs for each Arabidopsis gene. However, the relative frequency of protein domains in the two genomes is similar. Overrepresented exceptions in Populus include genes associated with lignocellulosic wall biosynthesis, meristem development, disease resistance, and metabolite transport.

Radiation-driven hydrodynamics of high- hohlraums on the national ignition facility.

The first hohlraum experiments on the National Ignition Facility (NIF) using the initial four laser beams tested radiation temperature limits imposed by plasma filling. For a variety of hohlraum sizes and pulse lengths, the measured x-ray flux shows signatures of filling that coincide with hard x-ray emission from plasma streaming out of the hohlraum. These observations agree with hydrodynamic simulations and with an analytical model that includes hydrodynamic and coronal radiative losses. The modeling predicts radiation temperature limits with full NIF (1.8 MJ), greater, and of longer duration than required for ignition hohlraums.

The effect of GIRK2(wv) on neurite growth, protein expression, and viability in the CNS-derived neuronal cell line, CATH.A-differentiated.

Death occurs in the homozygous mutant mouse weaver among several classes of neuron in cerebellum and ventral midbrain, because these neurons carry a mutation in the G protein-gated inwardly rectifying potassium channel, Girk2. GIRK2 is expressed in all neuronal types killed by wv in cerebellum and midbrain as well as in neurons elsewhere that suffer lesser consequences. GIRK2(wv) affects neurons postnatally, after proliferation, at the time of final differentiation. To assess the impact of GIRK2(wv) on neuronal development and viability, we introduced cDNA encoding wild-type and mutant channels into a variant of a CNS derived catecholamine cell line (Cath.a) known as Cath.a-differentiated. When cultured in serum-free medium, Cath.a-differentiated cells cease proliferation and undergo morphological differentiation, growing long neurites. Cath.a-differentiated cells do not express endogenous Girk channels. Transfection of GIRK2(wv) resulted in the death of Cath.a-differentiated cells, in a cDNA-concentration dependent manner. The highest concentration of Girk2(wv) cDNA caused loss of about half the cells, the next highest concentration one-third, and the least had no effect on viability. However, even the lowest concentration resulted in disruption of neurite outgrowth and reduced the protein products of co-transfected genes. High concentrations of MK801, which prevent Na(+) influx through the mutant channel, prevented death induced by GIRK2(wv). Cell death and disruption of neurite outgrowth were counteracted in GIRK2(wv)-expressing cells by the presence of an unrelated inwardly rectifying potassium channel, Kir2.3. These results are consistent with wv being a gain-of-function mutation, causing disruption of cellular homeostasis by mechanisms such as increased Na(+) influx and chronic depolarization which may in turn result in an excessive metabolic burden on the cell.

A comparative map of bovine chromosome 19 based on a combination of mapping on a bacterial artificial chromosome scaffold map, a whole genome radiation hybrid panel and the human draft sequence.

We have constructed a medium density physical map of bovine chromosome 19 using a combination of mapping loci on both a bovine bacterial artificial chromosome (BAC) scaffold map and a whole genome radiation hybrid (WGRH) panel. The resulting map contains 70 loci spanning the length of bovine chromosome 19. Three contiguous groups of BACs were identified on the basis of multiple loci mapping to individual BAC clones. Bovine chromosome 19 was found in this study to be comprised almost entirely from regions of human chromosome 17, with a small region putatively assigned to human chromosome 10. Fourteen breakpoints between the bovine and human chromosomes were detected, with a possibility of five more based on ordering of the WGRH map.

Resuspension of DNA sequencing reaction products in agarose increases sequence quality on an automated sequencer.

We are investigating approaches to increase DNA sequencing quality. Since a majorfactor in sequence generation is the cost of reagents and sample preparations, we have developed and optimized methods to sequence directly plasmid DNA isolated from alkaline lysis preparations. These methods remove the costly PCR and post-sequencing purification steps but can result in low sequence quality when using standard resuspension protocols on some sequencing platforms. This work outlines a simple, robust, and inexpensive resuspension protocol for DNA sequencing to correct this shortcoming. Resuspending the sequenced products in agarose before electrophoresis results in a substantial and reproducible increase in sequence quality and read length over resuspension in deionized water and has allowed us to use the aforementioned sample preparation methods to cut considerably the overall sequencing costs without sacrificing sequence quality. We demonstrate that resuspension of unpurified sequence products generated from template DNA isolated by a modified alkaline lysis technique in low concentrations of agarose yields a 384% improvement in sequence quality compared to resuspension in deionized water. Utilizing this protocol, we have produced more than 74,000 high-quality, long-read-length sequences from plasmid DNA template on the MegaBACET 1000 platform.