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- Erratum: "Label-free electronic probing of nucleic acids and proteins at the nanoscale using the nanoneedle biosensor" [Biomicrofluidics 7, 044114 (2013)].Esfandyarpour R, Javanmard M, Koochak Z, Esfandyarpour H, Harris JS, Davis RWBiomicrofluidics
- Five-dimensional visualization of phase transition in BiNiO3 under high pressure.Liu Y, Wang J, Azuma M, Mao WL, Yang WAppl Phys Lett
- Visuospatial selective attention in chickens.Sridharan D, Ramamurthy DL, Schwarz JS, Knudsen EIProc Natl Acad Sci U S A
- Response to letter regarding article, "transplantation for idiopathic pulmonary arterial hypertension: improvement in the lung allocation score era".Schaffer JM, Singh SK, Joyce DL, Reitz BA, Robbins RC, Zamanian RT, Mallidi HRCirculation
- Comparison of R2' measurement methods in the normal brain at 3 tesla.Ni W, Christen T, Zun Z, Zaharchuk GMagn Reson Med
- Arterial cerebral blood volume-weighted functional MRI using pseudocontinuous arterial spin tagging (AVAST).Jahanian H, Peltier S, Noll DC, Hernandez Garcia LMagn Reson Med
- Assessing the goodness of fit of personal risk models.Gong G, Quante AS, Terry MB, Whittemore ASStat Med
- Effective Solution- and Vacuum-Processed n-Doping by Dimers of Benzimidazoline Radicals.Naab BD, Zhang S, Vandewal K, Salleo A, Barlow S, Marder SR, Bao ZAdv Mater
- An intragenic long noncoding RNA interacts epigenetically with the RUNX1 promoter and enhancer chromatin DNA in hematopoietic malignancies.Wang H, Li W, Guo R, Sun J, Cui J, Wang G, Hoffman AR, Hu JFInt J Cancer
- Season of birth and risk of Hodgkin and non-Hodgkin lymphoma.Crump C, Sundquist J, Sieh W, Winkleby MA, Sundquist KInt J Cancer
- Interstitial lung disease in children.Kuo CS, Young LRCurr Opin Pediatr
- Sedative and analgesic use on night and day shifts in a pediatric cardiovascular intensive care unit.Staveski SL, Tesoro TM, Cisco MJ, Roth SJ, Shin AYAACN Adv Crit Care
- N-terminal pro-brain natriuretic Peptide is a useful prognostic marker in patients with pre-capillary pulmonary hypertension and renal insufficiency.Harbaum L, Hennigs JK, Baumann HJ, Lüneburg N, Griesch E, Bokemeyer C, Grünig E, Klose HPLoS One
- Light management for photovoltaics using high-index nanostructures.Brongersma ML, Cui Y, Fan SNat Mater
- Baseline Metabolic Tumor Volume and Total Lesion Glycolysis Are Associated With Survival Outcomes in Patients With Locally Advanced Pancreatic Cancer Receiving Stereotactic Body Radiation Therapy.Dholakia AS, Chaudhry M, Leal JP, Chang DT, Raman SP, Hacker-Prietz A, Su Z, Pai J, Oteiza KE, Griffith ME, Wahl RL, Tryggestad E, Pawlik T, Laheru DA, Wolfgang CL, Koong AC, Herman JMInt J Radiat Oncol Biol Phys
- Shorter gaze duration for happy faces in current but not remitted depression: Evidence from eye movements.Isaac L, Vrijsen JN, Rinck M, Speckens A, Becker ESPsychiatry Res
- Effect of adjunctive benzodiazepines on clinical outcomes in lithium- or quetiapine-treated outpatients with bipolar I or II disorder: Results from the Bipolar CHOICE trial.Bobo WV, Reilly-Harrington NA, Ketter TA, Brody BD, Kinrys G, Kemp DE, Shelton RC, McElroy SL, Sylvia LG, Kocsis JH, McInnis MG, Friedman ES, Singh V, Tohen M, Bowden CL, Deckersbach T, Calabrese JR, Thase ME, Nierenberg AA, Rabideau DJ, Schoenfeld DA, Faraone SV, Kamali MJ Affect Disord
- The complex choreography of transcription-coupled repair.Spivak G, Ganesan AKDNA Repair (Amst)
- Combination of Racial/Ethnic and Etiology/Disease-Specific Factors are associated with Lower Survival following Liver Transplantation in African Americans: An Analysis from UNOS/OPTN Database.Wong RJ, Ahmed AClin Transplant
- Racial/ethnic variations in perineal length and association with perineal lacerations: a prospective cohort study.Yeaton-Massey A, Wong L, Sparks TN, Handler SJ, Meyer MR, Granados JM, Stasenko M, Sit A, Caughey ABJ Matern Fetal Neonatal Med
- Images in clinical medicine. Bilateral digital ischemia.Rosenberg JM, Rosenberg RN Engl J Med
- [An allergic response to fight against venoms].Marichal T, Starkl P, Metz M, Galli SJMed Sci (Paris)
- Pulling out the 1%: whole-genome capture for the targeted enrichment of ancient DNA sequencing libraries.Carpenter ML, Buenrostro JD, Valdiosera C, Schroeder H, Allentoft ME, Sikora M, Rasmussen M, Gravel S, Guillén S, Nekhrizov G, Leshtakov K, Dimitrova D, Theodossiev N, Pettener D, Luiselli D, Sandoval K, Moreno-Estrada A, Li Y, Wang J, Gilbert MT, Willerslev E, Greenleaf WJ, Bustamante CDAm J Hum Genet
- Comparison of Medicare claims versus physician adjudication for identifying stroke outcomes in the Women's Health Initiative.Lakshminarayan K, Larson JC, Virnig B, Fuller C, Allen NB, Limacher M, Winkelmayer WC, Safford MM, Burwen DRStroke
- Light in and sound out: emerging translational strategies for photoacoustic imaging.Zackrisson S, van de Ven SM, Gambhir SSCancer Res
- Association of aspirin dose and vorapaxar safety and efficacy in patients with non-ST-segment elevation acute coronary syndrome (from the TRACER Trial).Mahaffey KW, Huang Z, Wallentin L, Storey RF, Jennings LK, Tricoci P, White HD, Armstrong PW, Aylward PE, Moliterno DJ, Van de Werf F, Chen E, Leonardi S, Rorick T, Held C, Strony J, Harrington RAAm J Cardiol
- Identification of a permissible HLA mismatch in hematopoietic stem cell transplantation.Fernandez-Viña MA, Wang T, Lee SJ, Haagenson M, Aljurf M, Askar M, Battiwalla M, Baxter-Lowe LA, Gajewski J, Jakubowski AA, Marino S, Oudshoorn M, Marsh SG, Petersdorf EW, Schultz K, Turner EV, Waller EK, Woolfrey A, Umejiego J, Spellman SR, Setterholm MBlood
- Targeting a glioblastoma cancer stem-cell population defined by EGF receptor variant III.Emlet DR, Gupta P, Holgado-Madruga M, Del Vecchio CA, Mitra SS, Han SY, Li G, Jensen KC, Vogel H, Xu LW, Skirboll SS, Wong AJCancer Res
- Otolaryngology: "It's all Greek to me".Jackler RK, Mudry AOtolaryngol Head Neck Surg
- 4D CT lung ventilation images are affected by the 4D CT sorting method.Yamamoto T, Kabus S, Lorenz C, Johnston E, Maxim PG, Diehn M, Eclov N, Barquero C, Loo BW, Keall PJMed Phys
- History of simulation in medicine: from Resusci Annie to the Ann Myers Medical Center.Singh H, Kalani M, Acosta-Torres S, El Ahmadieh TY, Loya J, Ganju ANeurosurgery
- Filipino gout: a review.Prasad P, Krishnan EArthritis Care Res (Hoboken)
- Genetic dissection of a cell-autonomous neurodegenerative disorder: lessons learned from mouse models of Niemann-Pick disease type C.Lopez ME, Scott MPDis Model Mech
- MicroRNA-regulated non-viral vectors with improved tumor specificity in an orthotopic rat model of hepatocellular carcinoma.Ronald JA, Katzenberg R, Nielsen CH, Jae HJ, Hofmann LV, Gambhir SSGene Ther
- Psychosocial predictors of treatment response to cognitive-behavior therapy for late-life depression: an exploratory study.Marquett RM, Thompson LW, Reiser RP, Holland JM, O'Hara RM, Kesler SR, Stepanenko A, Bilbrey A, Rengifo J, Majoros A, Thompson DGAging Ment Health
- Smart surface for elution of protein-protein bound particles: nanonewton dielectrophoretic forces using atomic layer deposited oxides.Emaminejad S, Javanmard M, Dutton RW, Davis RWAnal Chem
Erratum: "Label-free electronic probing of nucleic acids and proteins at the nanoscale using the nanoneedle biosensor" [Biomicrofluidics 7, 044114 (2013)].
Biomicrofluidics. 2014 Mar;8(2):029901
Authors: Esfandyarpour R, Javanmard M, Koochak Z, Esfandyarpour H, Harris JS, Davis RW
[This corrects the article on p. 044114 in vol. 7.].
PMID: 24753738 [PubMed - as supplied by publisher]
Five-dimensional visualization of phase transition in BiNiO3 under high pressure.
Appl Phys Lett. 2014 Jan 27;104(4):043108
Authors: Liu Y, Wang J, Azuma M, Mao WL, Yang W
Colossal negative thermal expansion was recently discovered in BiNiO3 associated with a low density to high density phase transition under high pressure. The varying proportion of co-existing phases plays a key role in the macroscopic behavior of this material. Here, we utilize a recently developed X-ray Absorption Near Edge Spectroscopy Tomography method and resolve the mixture of high/low pressure phases as a function of pressure at tens of nanometer resolution taking advantage of the charge transfer during the transition. This five-dimensional (X, Y, Z, energy, and pressure) visualization of the phase boundary provides a high resolution method to study the interface dynamics of high/low pressure phase.
PMID: 24753622 [PubMed - as supplied by publisher]
Visuospatial selective attention in chickens.
Proc Natl Acad Sci U S A. 2014 Apr 21;
Authors: Sridharan D, Ramamurthy DL, Schwarz JS, Knudsen EI
Voluntary control of attention promotes intelligent, adaptive behaviors by enabling the selective processing of information that is most relevant for making decisions. Despite extensive research on attention in primates, the capacity for selective attention in nonprimate species has never been quantified. Here we demonstrate selective attention in chickens by applying protocols that have been used to characterize visual spatial attention in primates. Chickens were trained to localize and report the vertical position of a target in the presence of task-relevant distracters. A spatial cue, the location of which varied across individual trials, indicated the horizontal, but not vertical, position of the upcoming target. Spatial cueing improved localization performance: accuracy (d') increased and reaction times decreased in a space-specific manner. Distracters severely impaired perceptual performance, and this impairment was greatly reduced by spatial cueing. Signal detection analysis with an "indecision" model demonstrated that spatial cueing significantly increased choice certainty in localizing targets. By contrast, error-aversion certainty (certainty of not making an error) remained essentially constant across cueing protocols, target contrasts, and individuals. The results show that chickens shift spatial attention rapidly and dynamically, following principles of stimulus selection that closely parallel those documented in primates. The findings suggest that the mechanisms that control attention have been conserved through evolution, and establish chickens-a highly visual species that is easily trained and amenable to cutting-edge experimental technologies-as an attractive model for linking behavior to neural mechanisms of selective attention.
PMID: 24753566 [PubMed - as supplied by publisher]
Response to letter regarding article, "transplantation for idiopathic pulmonary arterial hypertension: improvement in the lung allocation score era".
Circulation. 2014 Apr 22;129(16):e458
Authors: Schaffer JM, Singh SK, Joyce DL, Reitz BA, Robbins RC, Zamanian RT, Mallidi HR
PMID: 24753555 [PubMed - in process]
Comparison of R2' measurement methods in the normal brain at 3 tesla.
Magn Reson Med. 2014 Apr 18;
Authors: Ni W, Christen T, Zun Z, Zaharchuk G
PURPOSE: R2', the reversible component of transverse relaxation, is an important susceptibility measurement for studies of brain physiology and pathologies. In existing literature, different R2' measurement methods are used with assumption of equivalency. This study explores the choice of measurement method in healthy, young subjects at 3T.
METHODS: In this study, a modified gradient-echo sampling of free induction decay and echo (GESFIDE) sequence was used to compare four standard R2' measurement methods: asymmetric spin echo (ASE), standard GESFIDE, gradient echo sampling of the spin echo (GESSE), and separate R2 and R2* mapping.
RESULTS: GESSE returned lower R2' measurements than other methods (P < 0.05). Intersubject mean R2' in gray matter was found to be 2.7 s(-1) using standard GESFIDE and GESSE, versus 3.4-3.8 s(-1) using other methods. In white matter, mean R2' from GESSE was 2.3 s(-1) while other methods produced 3.7-4.3 s(-1) . R2 correction was applied to partially reduce the discrepancies between the methods, but significant differences remained, likely due to violation of the fundamental assumption of a single-compartmental tissue model, and hence monoexponential decay.
CONCLUSION: R2' measurements are influenced significantly by the choice of method. Awareness of this issue is important when designing and interpreting studies that involve R2' measurements. Magn Reson Med, 2014. © 2014 Wiley Periodicals, Inc.
PMID: 24753286 [PubMed - as supplied by publisher]
Arterial cerebral blood volume-weighted functional MRI using pseudocontinuous arterial spin tagging (AVAST).
Magn Reson Med. 2014 Apr 18;
Authors: Jahanian H, Peltier S, Noll DC, Hernandez Garcia L
PURPOSE: Neurovascular regulation, including responses to neural activation that give rise to the blood oxygenation level-dependent (BOLD) effect, occurs mainly at the arterial and arteriolar level. The purpose of this study is to develop a framework for fast imaging of arterial cerebral blood volume (aCBV) signal suitable for functional imaging studies.
METHODS: A variant of the pseudocontinuous arterial spin tagging technique was developed in order to achieve a contrast that depends on aCBV with little contamination from perfusion signal by taking advantage of the kinetics of the tag through the vasculature. This technique tailors the tagging duration and repetition time for each subject. The proposed technique, called AVAST, is compared empirically with BOLD imaging and standard (perfusion-weighted) arterial spin labeling (ASL) technique, in a motor-visual activation paradigm.
RESULTS: The average Z-scores in the activated area obtained over all the subjects were 4.25, 5.52, and 7.87 for standard ASL, AVAST, and BOLD techniques, respectively. The aCBV contrast obtained from AVAST provided 80% higher average signal-to-noise ratio and 95% higher average contrast-to-noise ratio compared with that of the standard ASL measurements.
CONCLUSION: AVAST exhibits improved activation detection sensitivity and temporal resolution over the standard ASL technique, in functional MRI experiments, while preserving its quantitative nature and statistical advantages. AVAST particularly could be useful in clinical studies of pathological conditions, longitudinal studies of cognitive function, and studies requiring sustained periods of the condition. Magn Reson Med, 2014. © 2014 Wiley Periodicals, Inc.
PMID: 24753198 [PubMed - as supplied by publisher]
Assessing the goodness of fit of personal risk models.
Stat Med. 2014 Apr 22;
Authors: Gong G, Quante AS, Terry MB, Whittemore AS
We describe a flexible family of tests for evaluating the goodness of fit (calibration) of a pre-specified personal risk model to the outcomes observed in a longitudinal cohort. Such evaluation involves using the risk model to assign each subject an absolute risk of developing the outcome within a given time from cohort entry and comparing subjects' assigned risks with their observed outcomes. This comparison involves several issues. For example, subjects followed only for part of the risk period have unknown outcomes. Moreover, existing tests do not reveal the reasons for poor model fit when it occurs, which can reflect misspecification of the model's hazards for the competing risks of outcome development and death. To address these issues, we extend the model-specified hazards for outcome and death, and use score statistics to test the null hypothesis that the extensions are unnecessary. Simulated cohort data applied to risk models whose outcome and mortality hazards agreed and disagreed with those generating the data show that the tests are sensitive to poor model fit, provide insight into the reasons for poor fit, and accommodate a wide range of model misspecification. We illustrate the methods by examining the calibration of two breast cancer risk models as applied to a cohort of participants in the Breast Cancer Family Registry. The methods can be implemented using the Risk Model Assessment Program, an R package freely available at http://stanford.edu/~ggong/rmap/. Copyright © 2014 John Wiley & Sons, Ltd.
PMID: 24753038 [PubMed - as supplied by publisher]
Effective Solution- and Vacuum-Processed n-Doping by Dimers of Benzimidazoline Radicals.
Adv Mater. 2014 Apr 19;
Authors: Naab BD, Zhang S, Vandewal K, Salleo A, Barlow S, Marder SR, Bao Z
Benzimidazoline radical dimers that can be handled in air but that function as powerful reductants are reported and evaluated as n-dopants by solution- and vacuum-processing. In several host materials, one of these dimers is found to have a more consistent doping effect than a hydride-donor dopant analog. Notably, a record high room-temperature conductivity of 12.0 S cm(-1) is obtained for doped C60 .
PMID: 24753007 [PubMed - as supplied by publisher]
An intragenic long noncoding RNA interacts epigenetically with the RUNX1 promoter and enhancer chromatin DNA in hematopoietic malignancies.
Int J Cancer. 2014 Apr 20;
Authors: Wang H, Li W, Guo R, Sun J, Cui J, Wang G, Hoffman AR, Hu JF
RUNX1, a master regulator of hematopoiesis, is the most commonly perturbed target of chromosomal abnormalities in hematopoietic malignancies. The t(8;21) translocation is found in 30%-40% of cases of acute myeloid leukemia (AML). Recent whole-exome sequencing also reveals mutations and deletions of RUNX1 in some solid tumors. We describe a RUNX1-intragenic long noncoding RNA ROPNR that is transcribed as unspliced transcript from an upstream overlapping promoter. ROPNR was upregulated in AML samples and in response to Ara-C treatment in vitro. ROPNR utilizes its 3'-terminal fragment to directly interact with the RUNX1 promoter and enhancers and participates in the orchestration of an intrachromosomal loop. The 3' region of ROPNR also participates in long-range interchromosomal interactions with chromatin regions that are involved in multiple RUNX1 translocations. These data suggest that ROPNR noncoding RNA may function as a previously unidentified candidate component that is involved in chromosomal translocation in hematopoietic malignancies. © 2014 Wiley Periodicals, Inc.
PMID: 24752773 [PubMed - as supplied by publisher]
Season of birth and risk of Hodgkin and non-Hodgkin lymphoma.
Int J Cancer. 2014 Apr 18;
Authors: Crump C, Sundquist J, Sieh W, Winkleby MA, Sundquist K
Infectious etiologies have been hypothesized for Hodgkin and non-Hodgkin lymphoma (HL and NHL) in early life, but findings to date for specific lymphomas and periods of susceptibility are conflicting. We conducted the first national cohort study to examine whether season of birth, a proxy for infectious exposures in the first few months of life, is associated with HL or NHL in childhood through young adulthood. A total of 3,571,574 persons born in Sweden in 1973-2008 were followed up through 2009 to examine the association between season of birth and incidence of HL (943 cases) or NHL (936 cases). We found a sinusoidal pattern in NHL risk by season of birth (P=0.04), with peak risk occurring among birthdates in April. Relative to persons born in fall (September-November), odds ratios for NHL by season of birth were 1.25 (95% CI, 1.04-1.50; P=0.02) for spring (March-May), 1.22 (95% CI, 1.01-1.48; P=0.04) for summer (June-August), and 1.11 (95% CI, 0.91-1.35; P=0.29) for winter (December-February). These findings did not vary by sex, age at diagnosis, or major subtypes. In contrast, there was no seasonal association between birthdate and risk of HL (P=0.78). In this large cohort study, birth in spring or summer was associated with increased risk of NHL (but not HL) in childhood through young adulthood, possibly related to immunologic effects of delayed infectious exposures compared with fall or winter birth. These findings suggest that immunologic responses in early infancy may play an important role in the development of NHL. © 2014 Wiley Periodicals, Inc.
PMID: 24752499 [PubMed - as supplied by publisher]
Interstitial lung disease in children.
Curr Opin Pediatr. 2014 Apr 18;
Authors: Kuo CS, Young LR
PURPOSE OF REVIEW: There has been tremendous progress in the approach to childhood interstitial lung diseases (chILD), with particular recognition that interstitial lung disease (ILD) in infants is often distinct from the forms that occur in older children and adults. Diagnosis is challenging because of the rarity of ILD and the fact that the presenting symptoms of ILD often overlap those of common respiratory disorders. This review summarizes the newly published recommendations for diagnosis and management, and highlights the recent scientific advances in several specific forms of chILD.
RECENT FINDINGS: Clinical practice guidelines emphasize the role for chest computed tomography, genetic testing, and lung biopsy in the diagnostic evaluation of children with suspected ILD. Recent studies have better defined the characteristics and molecular understanding of several different forms of ILD, including neuroendocrine cell hyperplasia of infancy and ILD, due to mutations in genes affecting surfactant production and metabolism. Despite significant progress, definitive therapies are often lacking.
SUMMARY: chILD encompasses a collection of rare, diffuse lung diseases. Timely recognition of children with suspected ILD and initiation of appropriate diagnostic evaluations will facilitate medical management. Systematic approaches to clinical care and further studies are needed to improve the outcomes of children with these rare disorders.
PMID: 24752172 [PubMed - as supplied by publisher]
Sedative and analgesic use on night and day shifts in a pediatric cardiovascular intensive care unit.
AACN Adv Crit Care. 2014 Apr-Jun;25(2):114-8
Authors: Staveski SL, Tesoro TM, Cisco MJ, Roth SJ, Shin AY
INTRODUCTION: The use of sedative and analgesic medications is directly linked to patient outcomes. The practice of administering as-needed sedative or analgesic medications deserves further exploration. We hypothesized that important variations exist in the practice of administering as-needed medications in the intensive care unit (ICU). We aimed to determine the influence of time of day on the practice of administering as-needed sedative or analgesic medications to children in the ICU.
METHODS: Medication administration records of patients admitted to our pediatric cardiovascular ICU during a 4-month period were reviewed to determine the frequency and timing of as-needed medication usage by shift.
RESULTS: A total of 152 ICU admissions (1854 patient days) were reviewed. A significantly greater number of as-needed doses were administered during the night shift (fentanyl, P = .005; lorazepam, P = .03; midazolam, P = .0003; diphenhydramine, P = .0003; and chloral hydrate, P = .0006). These differences remained statistically significant after excluding doses given during the first 6 hours after cardiovascular surgery. Morphine administration was similar between shifts (P = .08).
CONCLUSIONS: We identified a pattern of increased administration of as-needed sedative or analgesic medications during nights. Further research is needed to identify the underlying causes of this practice variation.
PMID: 24752023 [PubMed - in process]
N-terminal pro-brain natriuretic Peptide is a useful prognostic marker in patients with pre-capillary pulmonary hypertension and renal insufficiency.
PLoS One. 2014;9(4):e94263
Authors: Harbaum L, Hennigs JK, Baumann HJ, Lüneburg N, Griesch E, Bokemeyer C, Grünig E, Klose H
N-terminal pro-brain natriuretic peptide (NT-proBNP) is a routinely used prognostic parameter in patients with pre-capillary pulmonary hypertension (PH). As it accumulates in the presence of impaired renal function, the clinical utility of NT-proBNP in PH patients with concomitant renal insufficiency remains unclear. In a retrospective approach, patients with pre-capillary PH (group I or IV) and concomitant renal insufficiency at time of right heart catheterization (glomerular filtration rate (GFR) ≤60 ml/min/1.73 m2) were identified out of all prevalent pre-capillary PH patients treated at a single center. Forty patients with renal insufficiency (25.8%) were identified and matched regarding hemodynamic parameters with a control group of 56 PH patients with normal renal function (GFR >60 ml/min/1.73 m2). Correlations of NT-proBNP levels with hemodynamic and prognostic parameters (time to clinical worsening and overall survival) were assessed. Overall, GFR correlated inversely with NT-proBNP and had the strongest influence on NT-proBNP levels in a stepwise multiple linear regression model including hemodynamic parameters and age (r2 = 0.167). PH patients with renal insufficiency had significant higher levels of NT-proBNP (median: 1935 ng/l vs. 573 ng/l, p = 0.001). Nevertheless, NT-proBNP correlated with invasive hemodynamic parameters in these patients. Using higher cut-off values than in patients with preserved renal function, NT-proBNP levels were significantly associated with time to clinical worsening (>1660 ng/l, p = 0.001) and survival (>2212 ng/l, p = 0.047) in patients with renal insufficiency. Multivariate Cox's proportional hazards analysis including established prognostic parameters, age and GFR confirmed NT-proBNP as an independent risk factor for clinical worsening in PH patients with renal insufficiency (hazard ratio 4.8, p = 0.007). Thus, in a retrospective analysis we showed that NT-proBNP levels correlated with hemodynamic parameters and outcome regardless of renal function. By using higher cut-off values, NT-proBNP seems to represent a valid clinical marker even in PH patients with renal insufficiency.
PMID: 24751887 [PubMed - in process]
Light management for photovoltaics using high-index nanostructures.
Nat Mater. 2014 Apr 22;13(5):451-60
Authors: Brongersma ML, Cui Y, Fan S
High-performance photovoltaic cells use semiconductors to convert sunlight into clean electrical power, and transparent dielectrics or conductive oxides as antireflection coatings. A common feature of these materials is their high refractive index. Whereas high-index materials in a planar form tend to produce a strong, undesired reflection of sunlight, high-index nanostructures afford new ways to manipulate light at a subwavelength scale. For example, nanoscale wires, particles and voids support strong optical resonances that can enhance and effectively control light absorption and scattering processes. As such, they provide ideal building blocks for novel, broadband antireflection coatings, light-trapping layers and super-absorbing films. This Review discusses some of the recent developments in the design and implementation of such photonic elements in thin-film photovoltaic cells.
PMID: 24751773 [PubMed - in process]
Baseline Metabolic Tumor Volume and Total Lesion Glycolysis Are Associated With Survival Outcomes in Patients With Locally Advanced Pancreatic Cancer Receiving Stereotactic Body Radiation Therapy.
Int J Radiat Oncol Biol Phys. 2014 Apr 18;
Authors: Dholakia AS, Chaudhry M, Leal JP, Chang DT, Raman SP, Hacker-Prietz A, Su Z, Pai J, Oteiza KE, Griffith ME, Wahl RL, Tryggestad E, Pawlik T, Laheru DA, Wolfgang CL, Koong AC, Herman JM
PURPOSE: Although previous studies have demonstrated the prognostic value of positron emission tomography (PET) parameters in other malignancies, the role of PET in pancreatic cancer has yet to be well established. We analyzed the prognostic utility of PET for patients with locally advanced pancreatic cancer (LAPC) undergoing fractionated stereotactic body radiation therapy (SBRT).
MATERIALS AND METHODS: Thirty-two patients with LAPC in a prospective clinical trial received up to 3 doses of gemcitabine, followed by 33 Gy in 5 fractions of 6.6 Gy, using SBRT. All patients received a baseline PET scan prior to SBRT (pre-SBRT PET). Metabolic tumor volume (MTV), total lesion glycolysis (TLG), and maximum and peak standardized uptake values (SUVmax and SUVpeak) on pre-SBRT PET scans were calculated using custom-designed software. Disease was measured at a threshold based on the liver SUV, using the equation Livermean + [2 × Liversd]. Median values of PET parameters were used as cutoffs when assessing their prognostic potential through Cox regression analyses.
RESULTS: Of the 32 patients, the majority were male (n=19, 59%), 65 years or older (n=21, 66%), and had tumors located in the pancreatic head (n=27, 84%). Twenty-seven patients (84%) received induction gemcitabine prior to SBRT. Median overall survival for the entire cohort was 18.8 months (95% confidence interval [CI], 15.7-22.0). An MTV of 26.8 cm(3) or greater (hazard ratio [HR] 4.46, 95% CI 1.64-5.88, P<.003) and TLG of 70.9 or greater (HR 3.08, 95% CI 1.18-8.02, P<.021) on pre-SBRT PET scan were associated with inferior overall survival on univariate analysis. Both pre-SBRT MTV (HR 5.13, 95% CI 1.19-22.21, P=.029) and TLG (HR 3.34, 95% CI 1.07-10.48, P=.038) remained independently associated with overall survival in separate multivariate analyses.
CONCLUSIONS: Pre-SBRT MTV and TLG are potential predictive factors for overall survival in patients with LAPC and may assist in tailoring therapy.
PMID: 24751410 [PubMed - as supplied by publisher]
Shorter gaze duration for happy faces in current but not remitted depression: Evidence from eye movements.
Psychiatry Res. 2014 Apr 12;
Authors: Isaac L, Vrijsen JN, Rinck M, Speckens A, Becker ES
Cognitive theories of depression propose that depressed individuals preferentially attend to negative information and that such cognitive biases constitute important vulnerability and maintenance factors for the disorder. Most studies examined this bias by registration of response latencies. The present study employed a direct and continuous measurement of attentional processing for emotional stimuli by recording eye movements. Currently depressed (CD), remitted depressed (RD) and healthy control (HC) participants viewed slides presenting sad, angry, happy and neutral facial expressions. For each expression, four components of visual attention were analyzed: first fixation, maintained fixation, relative fixation frequency and glance duration. Results showed that healthy controls were characterized by longer gaze duration for happy faces compared to currently depressed individuals but not compared to remitted depressed individuals. Both patient groups (CD, RD) demonstrated longer maintained fixation (dwelling time) on all emotional faces compared to healthy controls. The present findings are in line with the presumption that depression is associated with a loss of elaborative processing of positive stimuli that characterizes healthy controls. Importantly, successful remission of depression (RD group) may result in positive attentional processing as no group differences were found between healthy controls and remitted patients on glance duration for happy faces.
PMID: 24751380 [PubMed - as supplied by publisher]
Effect of adjunctive benzodiazepines on clinical outcomes in lithium- or quetiapine-treated outpatients with bipolar I or II disorder: Results from the Bipolar CHOICE trial.
J Affect Disord. 2014 Jun;161:30-5
Authors: Bobo WV, Reilly-Harrington NA, Ketter TA, Brody BD, Kinrys G, Kemp DE, Shelton RC, McElroy SL, Sylvia LG, Kocsis JH, McInnis MG, Friedman ES, Singh V, Tohen M, Bowden CL, Deckersbach T, Calabrese JR, Thase ME, Nierenberg AA, Rabideau DJ, Schoenfeld DA, Faraone SV, Kamali M
BACKGROUND: Little is known about the longer-term effects of adjunctive benzodiazepines on symptom response during treatment in patients with bipolar disorders.
METHODS: The study sample consisted of 482 patients with bipolar I or II disorder enrolled in a 6-month, randomized, multi-site comparison of lithium- and quetiapine-based treatment. Changes in clinical measures (BISS total and subscales, CGI-BP, and CGI-Efficacy Index) were compared between participants who did and did not receive benzodiazepine treatment at baseline or during follow-up. Selected outcomes were also compared between patients who did and did not initiate benzodiazepines during follow-up using stabilized inverse probability weighted analyses.
RESULTS: Significant improvement in all outcome measures occurred within each benzodiazepine exposure group. Benzodiazepine users (at baseline or during follow-up) experienced significantly less improvement in BISS total, BISS irritability, and CGI-BP scores than did benzodiazepine non-users. There were no significant differences in these measures between patients who did and did not initiate benzodiazepines during follow-up in the weighted analyses. There was no significant effect of benzodiazepine use on any outcome measure in patients with comorbid anxiety or substance use disorders.
LIMITATIONS: This is a secondary analysis of data from a randomized effectiveness trial that was not designed to address differential treatment response according to benzodiazepine use.
CONCLUSIONS: Adjunctive benzodiazepines may not significantly affect clinical outcome in lithium- or quetiapine-treated patients with bipolar I or II disorder over 6 months, after controlling for potential confounding factors.
PMID: 24751304 [PubMed - in process]
The complex choreography of transcription-coupled repair.
DNA Repair (Amst). 2014 Apr 18;
Authors: Spivak G, Ganesan AK
A quarter of a century has elapsed since the discovery of transcription-coupled repair (TCR), and yet our fascination with this process has not diminished. Nucleotide excision repair (NER) is a versatile pathway that removes helix-distorting DNA lesions from the genomes of organisms across the evolutionary scale, from bacteria to humans. TCR, defined as a subpathway of NER, is dedicated to the repair of lesions that, by virtue of their location on the transcribed strands of active genes, encumber elongation by RNA polymerases. In this review, we will report on newly identified proteins, protein modifications, and protein complexes that participate in TCR in Escherichia coli and in human cells. We will discuss general models for the biochemical pathways and how and when cells might choose to utilize TCR or other pathways for repair or bypass of transcription-blocking DNA alterations.
PMID: 24751236 [PubMed - as supplied by publisher]
Combination of Racial/Ethnic and Etiology/Disease-Specific Factors are associated with Lower Survival following Liver Transplantation in African Americans: An Analysis from UNOS/OPTN Database.
Clin Transplant. 2014 Apr 21;
Authors: Wong RJ, Ahmed A
Higher rates of hepatitis C virus (HCV) recurrence and lower response to HCV anti-viral therapy contribute to the lower post-liver transplantation (LT) survival among African Americans with HCV. The current study aims to evaluate race/ethnicity-specific and etiology-specific factors contributing to lower post-LT survival among African Americans in the U.S. The 2002-2012 United Network for Organ Sharing registry was utilized to evaluate race/ethnicity-specific post-LT survival among patients with HCV, hepatocellular carcinoma (HCC), alcoholic liver disease (ALD), nonalcoholic steatohepatitis, and cryptogenic cirrhosis. From 2002-2012, HCV was the leading indication for LT. While African Americans accounted for 9.5% of all LT during this period, they had the lowest overall and etiology-specific 5-year post-LT survival. On multivariate Cox proportional hazards modeling, African Americans had significantly lower post-LT survival compared to non-Hispanic whites among patients with HCV (HR, 1.30; 95% CI, 1.19-1.41), HCC (HR, 1.49; 95% CI, 1.25-1.79) and ALD (HR, 1.52; 95% CI, 1.19-1.94). In conclusion, African Americans had the lowest post-LT survival among patients with HCV, HCC and ALD. Race/ethnicity and the etiology of chronic liver disease were observed to have a combined detrimental effect leading to lower survival following LT in African Americans. This article is protected by copyright. All rights reserved.
PMID: 24750171 [PubMed - as supplied by publisher]
Racial/ethnic variations in perineal length and association with perineal lacerations: a prospective cohort study.
J Matern Fetal Neonatal Med. 2014 Apr 22;
Authors: Yeaton-Massey A, Wong L, Sparks TN, Handler SJ, Meyer MR, Granados JM, Stasenko M, Sit A, Caughey AB
Objective: To examine the association between race/ethnicity, perineal length, and the risk of perineal laceration. Methods: This is a prospective cohort study of a diverse group of women with singleton gestations in the third trimester of pregnancy. Perineal length was measured and mean values calculated for several racial/ethnic groups. Chi-squared analyses were used to examine rates of severe perineal laceration (third or fourth degree laceration) by race/ethnicity among women considered to have a short perineal length. Further, subgroup analyses were performed comparing nulliparas to multiparas. Results: Among 344 study participants, there was no statistically significant difference in mean perineal length by race/ethnicity (White 4.0+/-1.1cm, African-American 3.7+/-1.0cm, Latina 4.1+/-1.1cm, Asian 3.8+/-1.0cm, and other/unknown 4.0+/-0.9cm). Considering parity, more multiparous Asian and African-American women had a short perineal length (20.7% and 23.5%, respectively, p=0.05). Finally, the rate of severe perineal lacerations in our cohort was 2.6% overall, but was 8.2% among Asian women (p=0.04). Conclusions: We did not find a relationship between short perineal length and risk of severe perineal laceration with vaginal delivery, or a difference in mean perineal length by maternal race/ethnicity. However, we did find that women of different racial/ethnic groups have varying rates of severe perineal laceration, with Asian women comprising the highest proportion.
PMID: 24749802 [PubMed - as supplied by publisher]
Images in clinical medicine. Bilateral digital ischemia.
N Engl J Med. 2014 Mar 20;370(12):1148
Authors: Rosenberg JM, Rosenberg R
PMID: 24645947 [PubMed - indexed for MEDLINE]
[An allergic response to fight against venoms].
Med Sci (Paris). 2014 Feb;30(2):127-30
Authors: Marichal T, Starkl P, Metz M, Galli SJ
PMID: 24572105 [PubMed - indexed for MEDLINE]
Pulling out the 1%: whole-genome capture for the targeted enrichment of ancient DNA sequencing libraries.
Am J Hum Genet. 2013 Nov 7;93(5):852-64
Authors: Carpenter ML, Buenrostro JD, Valdiosera C, Schroeder H, Allentoft ME, Sikora M, Rasmussen M, Gravel S, Guillén S, Nekhrizov G, Leshtakov K, Dimitrova D, Theodossiev N, Pettener D, Luiselli D, Sandoval K, Moreno-Estrada A, Li Y, Wang J, Gilbert MT, Willerslev E, Greenleaf WJ, Bustamante CD
Most ancient specimens contain very low levels of endogenous DNA, precluding the shotgun sequencing of many interesting samples because of cost. Ancient DNA (aDNA) libraries often contain <1% endogenous DNA, with the majority of sequencing capacity taken up by environmental DNA. Here we present a capture-based method for enriching the endogenous component of aDNA sequencing libraries. By using biotinylated RNA baits transcribed from genomic DNA libraries, we are able to capture DNA fragments from across the human genome. We demonstrate this method on libraries created from four Iron Age and Bronze Age human teeth from Bulgaria, as well as bone samples from seven Peruvian mummies and a Bronze Age hair sample from Denmark. Prior to capture, shotgun sequencing of these libraries yielded an average of 1.2% of reads mapping to the human genome (including duplicates). After capture, this fraction increased substantially, with up to 59% of reads mapped to human and enrichment ranging from 6- to 159-fold. Furthermore, we maintained coverage of the majority of regions sequenced in the precapture library. Intersection with the 1000 Genomes Project reference panel yielded an average of 50,723 SNPs (range 3,062-147,243) for the postcapture libraries sequenced with 1 million reads, compared with 13,280 SNPs (range 217-73,266) for the precapture libraries, increasing resolution in population genetic analyses. Our whole-genome capture approach makes it less costly to sequence aDNA from specimens containing very low levels of endogenous DNA, enabling the analysis of larger numbers of samples.
PMID: 24568772 [PubMed - indexed for MEDLINE]
Comparison of Medicare claims versus physician adjudication for identifying stroke outcomes in the Women's Health Initiative.
Stroke. 2014 Mar;45(3):815-21
Authors: Lakshminarayan K, Larson JC, Virnig B, Fuller C, Allen NB, Limacher M, Winkelmayer WC, Safford MM, Burwen DR
BACKGROUND AND PURPOSE: Many studies use medical record review for ascertaining outcomes. One large, longitudinal study, the Women's Health Initiative (WHI), ascertains strokes using participant self-report and subsequent physician review of medical records. This is resource-intensive. Herein, we assess whether Medicare data can reliably assess stroke events in the WHI.
METHODS: Subjects were WHI participants with fee-for-service Medicare. Four stroke definitions were created for Medicare data using discharge diagnoses in hospitalization claims: definition 1, stroke codes in any position; definition 2, primary position stroke codes; and definitions 3 and 4, hemorrhagic and ischemic stroke codes, respectively. WHI data were randomly split into training (50%) and test sets. A concordance matrix was used to examine the agreement between WHI and Medicare stroke diagnosis. A WHI stroke and a Medicare stroke were considered a match if they occurred within ±7 days of each other. Refined analyses excluded Medicare events when medical records were unavailable for comparison.
RESULTS: Training data consisted of 24 428 randomly selected participants. There were 577 WHI strokes and 557 Medicare strokes using definition 1. Of these, 478 were a match. With regard to algorithm performance, specificity was 99.7%, negative predictive value was 99.7%, sensitivity was 82.8%, positive predictive value was 85.8%, and κ=0.84. Performance was similar for test data. Whereas specificity and negative predictive value exceeded 99%, sensitivity ranged from 75% to 88% and positive predictive value ranged from 80% to 90% across stroke definitions.
CONCLUSIONS: Medicare data seem useful for population-based stroke research; however, performance characteristics depend on the definition selected.
PMID: 24525955 [PubMed - indexed for MEDLINE]
Light in and sound out: emerging translational strategies for photoacoustic imaging.
Cancer Res. 2014 Feb 15;74(4):979-1004
Authors: Zackrisson S, van de Ven SM, Gambhir SS
Photoacoustic imaging (PAI) has the potential for real-time molecular imaging at high resolution and deep inside the tissue, using nonionizing radiation and not necessarily depending on exogenous imaging agents, making this technique very promising for a range of clinical applications. The fact that PAI systems can be made portable and compatible with existing imaging technologies favors clinical translation even more. The breadth of clinical applications in which photoacoustics could play a valuable role include: noninvasive imaging of the breast, sentinel lymph nodes, skin, thyroid, eye, prostate (transrectal), and ovaries (transvaginal); minimally invasive endoscopic imaging of gastrointestinal tract, bladder, and circulating tumor cells (in vivo flow cytometry); and intraoperative imaging for assessment of tumor margins and (lymph node) metastases. In this review, we describe the basics of PAI and its recent advances in biomedical research, followed by a discussion of strategies for clinical translation of the technique.
PMID: 24514041 [PubMed - indexed for MEDLINE]
Association of aspirin dose and vorapaxar safety and efficacy in patients with non-ST-segment elevation acute coronary syndrome (from the TRACER Trial).
Am J Cardiol. 2014 Mar 15;113(6):936-44
Authors: Mahaffey KW, Huang Z, Wallentin L, Storey RF, Jennings LK, Tricoci P, White HD, Armstrong PW, Aylward PE, Moliterno DJ, Van de Werf F, Chen E, Leonardi S, Rorick T, Held C, Strony J, Harrington RA
Thrombin Receptor Antagonist for Clinical Event Reduction in Acute Coronary Syndrome (TRACER) trial compared vorapaxar and placebo in 12,944 high-risk patients with non-ST-segment elevation acute coronary syndrome. We explored aspirin (ASA) use and its association with outcomes. Kaplan-Meier event rates were compared in groups defined by ASA dose (low, medium, and high). Landmark analyses with covariate adjustment were performed for 0 to 30, 31 to 180, and 181 to 365 days. Of 12,515 participants, 7,523, 1,049, and 3,943 participants were treated with low-, medium-, and high-dose ASA at baseline, respectively. Participants enrolled in North America versus elsewhere were more often treated with a high dose at baseline (66% vs 19%) and discharge (60% vs 3%). Unadjusted cardiovascular death, myocardial infarction, stroke, hospitalization for ischemia, or urgent revascularization event rates tended to be higher with higher baseline ASA (18.45% low, 19.13% medium, and 20.27% high; p for trend = 0.15573). Unadjusted and adjusted hazard ratios (95% confidence intervals) for effect of vorapaxar on cardiovascular (unadjusted p for interaction = 0.065; adjusted p for interaction = 0.140) and bleeding (unadjusted p for interaction = 0.915; adjusted p for interaction = 0.954) outcomes were similar across groups. Landmark analyses showed similar safety and efficacy outcomes with vorapaxar and placebo by ASA dose at each time point except for 0 to 30 days, when vorapaxar tended to be worse for efficacy (hazard ratio 1.13, 95% confidence interval 0.89 to 1.44, p for interaction = 0.0157). In conclusion, most TRACER participants were treated with low-dose ASA, although a high dose was common in North America. High-dose participants tended to have higher rates of ischemic and bleeding outcomes. Although formal statistical testing did not reveal heterogeneity in vorapaxar's effect across dose subgroups, consistent trends support use of low-dose ASA with other antiplatelet therapies.
PMID: 24444781 [PubMed - indexed for MEDLINE]
Identification of a permissible HLA mismatch in hematopoietic stem cell transplantation.
Blood. 2014 Feb 20;123(8):1270-8
Authors: Fernandez-Viña MA, Wang T, Lee SJ, Haagenson M, Aljurf M, Askar M, Battiwalla M, Baxter-Lowe LA, Gajewski J, Jakubowski AA, Marino S, Oudshoorn M, Marsh SG, Petersdorf EW, Schultz K, Turner EV, Waller EK, Woolfrey A, Umejiego J, Spellman SR, Setterholm M
In subjects mismatched in the HLA alleles C*03:03/C*03:04 no allogeneic cytotoxic T-lymphocyte responses are detected in vitro. Hematopoietic stem cell transplantation (HSCT) with unrelated donors (UDs) showed no association between the HLA-C allele mismatches (CAMMs) and adverse outcomes; antigen mismatches at this and mismatches other HLA loci are deleterious. The absence of effect of the CAMM may have resulted from the predominance of the mismatch C*03:03/C*03:04. Patients with hematologic malignancies receiving UD HSCT matched in 8/8 and 7/8 HLA alleles were examined. Transplants mismatched in HLA-C antigens or mismatched in HLA-A, -B, or -DRB1 presented significant differences (P < .0001) in mortality (hazard ratio [HR] = 1.37, 1.30), disease-free survival (HR = 1.33, 1.27), treatment-related mortality (HR = 1.54, 1.54), and grade 3-4 acute graft-versus-host disease (HR = 1.49, 1.77) compared with the 8/8 group; transplants mismatched in other CAMMs had similar outcomes with HR ranging from 1.34 to 172 for these endpoints. The C*03:03/C*03:04 mismatched and the 8/8 matched groups had identical outcomes (HR ranging from 0.96-1.05). The previous finding that CAMMs do not associate with adverse outcomes is explained by the predominance (69%) of the mismatch C*03:03/03:04 in this group that is better tolerated than other HLA mismatches.
PMID: 24408320 [PubMed - indexed for MEDLINE]
Targeting a glioblastoma cancer stem-cell population defined by EGF receptor variant III.
Cancer Res. 2014 Feb 15;74(4):1238-49
Authors: Emlet DR, Gupta P, Holgado-Madruga M, Del Vecchio CA, Mitra SS, Han SY, Li G, Jensen KC, Vogel H, Xu LW, Skirboll SS, Wong AJ
The relationship between mutated proteins and the cancer stem-cell population is unclear. Glioblastoma tumors frequently express EGFRvIII, an EGF receptor (EGFR) variant that arises via gene rearrangement and amplification. However, expression of EGFRvIII is restricted despite the prevalence of the alteration. Here, we show that EGFRvIII is highly coexpressed with CD133 and that EGFRvIII(+)/CD133(+) defines the population of cancer stem cells (CSC) with the highest degree of self-renewal and tumor-initiating ability. EGFRvIII(+) cells are associated with other stem/progenitor markers, whereas markers of differentiation are found in EGFRvIII(-) cells. EGFRvIII expression is lost in standard cell culture, but its expression is maintained in tumor sphere culture, and cultured cells also retain the EGFRvIII(+)/CD133(+) coexpression, self-renewal, and tumor initiating abilities. Elimination of the EGFRvIII(+)/CD133(+) population using a bispecific antibody reduced tumorigenicity of implanted tumor cells better than any reagent directed against a single epitope. This work demonstrates that a mutated oncogene can have CSC-specific expression and be used to specifically target this population.
PMID: 24366881 [PubMed - indexed for MEDLINE]
Otolaryngology: "It's all Greek to me".
Otolaryngol Head Neck Surg. 2014 Mar;150(3):337-41
Authors: Jackler RK, Mudry A
This study explores the origins and evolution of the specialty name for what is now primarily known in the English-speaking world as otolaryngology-head and neck surgery. This appellation is the longest and least pronounceable of all medical specialties. While it is reasonably well understood among medical professionals, surveys show that only a small fraction of health consumers understand its meaning. The ideal medical specialty name should have a meaning recognizable to a large segment of the public, be easily pronounceable, be reasonably short, and serve to communicate the type of illnesses treated. The cumbersomeness of the specialty name has led to nearly universal use of informal substitutes, which do not covey the scope of contemporary practice (e.g., ear, nose, and throat) and to abbreviations (e.g., ENT, ORL, OHNS). Based on the commercial experience, it is clear that shorter is better. The authors advocate that dialog be opened, guided by the experience from instances of successful corporate rebranding, to consider possible alternatives.
PMID: 24316790 [PubMed - indexed for MEDLINE]
4D CT lung ventilation images are affected by the 4D CT sorting method.
Med Phys. 2013 Oct;40(10):101907
Authors: Yamamoto T, Kabus S, Lorenz C, Johnston E, Maxim PG, Diehn M, Eclov N, Barquero C, Loo BW, Keall PJ
PURPOSE: Four-dimensional (4D) computed tomography (CT) ventilation imaging is a novel promising technique for lung functional imaging. The current standard 4D CT technique using phase-based sorting frequently results in artifacts, which may deteriorate the accuracy of ventilation imaging. The purpose of this study was to quantify the variability of 4D CT ventilation imaging due to 4D CT sorting.
METHODS: 4D CT image sets from nine lung cancer patients were each sorted by the phase-based method and anatomic similarity-based method, designed to reduce artifacts, with corresponding ventilation images created for each method. Artifacts in the resulting 4D CT images were quantified with the artifact score which was defined based on the difference between the normalized cross correlation for CT slices within a CT data segment and that for CT slices bordering the interface between adjacent CT data segments. The ventilation variation was quantified using voxel-based Spearman rank correlation coefficients for all lung voxels, and Dice similarity coefficients (DSC) for the spatial overlap of low-functional lung volumes. Furthermore, the correlations with matching single-photon emission CT (SPECT) ventilation images (assumed ground truth) were evaluated for three patients to investigate which sorting method provides higher physiologic accuracy.
RESULTS: Anatomic similarity-based sorting reduced 4D CT artifacts compared to phase-based sorting (artifact score, 0.45 ± 0.14 vs 0.58 ± 0.24, p = 0.10 at peak-exhale; 0.63 ± 0.19 vs 0.71 ± 0.31, p = 0.25 at peak-inhale). The voxel-based correlation between the two ventilation images was 0.69 ± 0.26 on average, ranging from 0.03 to 0.85. The DSC was 0.71 ± 0.13 on average. Anatomic similarity-based sorting yielded significantly fewer lung voxels with paradoxical negative ventilation values than phase-based sorting (5.0 ± 2.6% vs 9.7 ± 8.4%, p = 0.05), and improved the correlation with SPECT ventilation regionally.
CONCLUSIONS: The variability of 4D CT ventilation imaging due to 4D CT sorting was moderate overall and substantial in some cases, suggesting that 4D CT artifacts are an important source of variations in 4D CT ventilation imaging. Reduction of 4D CT artifacts provided more physiologically convincing and accurate ventilation estimates. Further studies are needed to confirm this result.
PMID: 24089909 [PubMed - indexed for MEDLINE]
History of simulation in medicine: from Resusci Annie to the Ann Myers Medical Center.
Neurosurgery. 2013 Oct;73 Suppl 1:9-14
Authors: Singh H, Kalani M, Acosta-Torres S, El Ahmadieh TY, Loya J, Ganju A
Medical and surgical graduate medical education has historically used a halstedian approach of "see one, do one, teach one." Increased public demand for safety, quality, and accountability in the setting of regulated resident work hours and limited resources is driving the development of innovative educational tools. The use of simulation in nonmedical, medical, and neurosurgical disciplines is reviewed in this article. Simulation has been validated as an educational tool in nonmedical fields such as aviation and the military. Across most medical and surgical subspecialties, simulation is recognized as a valuable tool that will shape the next era of medical education, postgraduate training, and maintenance of certification.
PMID: 24051890 [PubMed - indexed for MEDLINE]
Filipino gout: a review.
Arthritis Care Res (Hoboken). 2014 Mar;66(3):337-43
Authors: Prasad P, Krishnan E
PMID: 23983155 [PubMed - indexed for MEDLINE]
Genetic dissection of a cell-autonomous neurodegenerative disorder: lessons learned from mouse models of Niemann-Pick disease type C.
Dis Model Mech. 2013 Sep;6(5):1089-100
Authors: Lopez ME, Scott MP
Understanding neurodegenerative disease progression and its treatment requires the systematic characterization and manipulation of relevant cell types and molecular pathways. The neurodegenerative lysosomal storage disorder Niemann-Pick disease type C (NPC) is highly amenable to genetic approaches that allow exploration of the disease biology at the organismal, cellular and molecular level. Although NPC is a rare disease, genetic analysis of the associated neuropathology promises to provide insight into the logic of disease neural circuitry, selective neuron vulnerability and neural-glial interactions. The ability to control the disorder cell-autonomously and in naturally occurring spontaneous animal models that recapitulate many aspects of the human disease allows for an unparalleled dissection of the disease neurobiology in vivo. Here, we review progress in mouse-model-based studies of NPC disease, specifically focusing on the subtype that is caused by a deficiency in NPC1, a sterol-binding late endosomal membrane protein involved in lipid trafficking. We also discuss recent findings and future directions in NPC disease research that are pertinent to understanding the cellular and molecular mechanisms underlying neurodegeneration in general.
PMID: 23907005 [PubMed - indexed for MEDLINE]
MicroRNA-regulated non-viral vectors with improved tumor specificity in an orthotopic rat model of hepatocellular carcinoma.
Gene Ther. 2013 Oct;20(10):1006-13
Authors: Ronald JA, Katzenberg R, Nielsen CH, Jae HJ, Hofmann LV, Gambhir SS
In hepatocellular carcinoma (HCC), tumor specificity of gene therapy is of utmost importance to preserve liver function. MicroRNAs (miRNAs) are powerful negative regulators of gene expression and many are downregulated in human HCC. We identified seven miRNAs that are also downregulated in tumors in a rat hepatoma model (P<0.05) and attempted to improve tumor specificity by constructing a panel of luciferase-expressing vectors containing binding sites for these miRNAs. Attenuation of luciferase expression by the corresponding miRNAs was confirmed across various cell lines and in mouse liver. We then tested our vectors in tumor-bearing rats and identified two miRNAs, miR-26a and miR-122, that significantly decreased expression in liver compared with the control vector (6.40 and 0.26%, respectively; P<0.05). In tumor, miR-122 had a nonsignificant trend towards decreased (∼50%) expression, whereas miR-26 had no significant effect on tumor expression. To our knowledge, this is the first work using differentially expressed miRNAs to de-target transgene expression in an orthotopic hepatoma model and to identify miR-26a, in addition to miR-122, for de-targeting liver. Considering the heterogeneity of miRNA expression in human HCC, this information will be important in guiding development of more personalized vectors for the treatment of this devastating disease.
PMID: 23719066 [PubMed - indexed for MEDLINE]
Psychosocial predictors of treatment response to cognitive-behavior therapy for late-life depression: an exploratory study.
Aging Ment Health. 2013;17(7):830-8
Authors: Marquett RM, Thompson LW, Reiser RP, Holland JM, O'Hara RM, Kesler SR, Stepanenko A, Bilbrey A, Rengifo J, Majoros A, Thompson DG
OBJECTIVE: The primary objective of this study was to examine a variety of potential predictors of response to Cognitive Behavioral Therapy (CBT) in depressed older adults.
METHOD: Sixty older adults with a clinical diagnosis of major or minor depression or dysthymic disorder received 12 individual sessions of CBT over a three- to four-month-period. The BDI-II was administered pre- and post-intervention to assess change in the level of depression. A cutoff score of 13 or less at post was used to determine positive treatment response. A variety of measures (obtained at baseline) were evaluated using hierarchical regression techniques to predict improvement following treatment.
RESULTS: Individuals who showed greater improvement were: (a) more open to new experiences; (b) less negatively affected by past stressors; (c) less inclined to have an external locus of control but more likely to cite others as responsible for negative stress in their lives; and (d) were more likely to seek emotional support when symptomatic. Lower education level and reported use of active coping strategies at baseline were associated with less improvement. Other variables (e.g., age, overall physical health, and cognitive status) were not associated with treatment response. Use of logistic regression to predict responders vs. nonresponders yielded a similar pattern.
CONCLUSION: These findings agree with prior research confirming the effectiveness of a brief CBT intervention for older depressed persons and suggest further exploration of several psychosocial factors that may contribute to a stronger response to CBT.
PMID: 23631698 [PubMed - indexed for MEDLINE]
Smart surface for elution of protein-protein bound particles: nanonewton dielectrophoretic forces using atomic layer deposited oxides.
Anal Chem. 2012 Dec 18;84(24):10793-801
Authors: Emaminejad S, Javanmard M, Dutton RW, Davis RW
By increasing the strength of the negative dielectrophoresis force, we demonstrated a significantly improved electrokinetic actuation and switching microsystem that can be used to elute specifically bound beads from the surface. In this work using atomic layer deposition we deposited a pinhole free nanometer-scale thin film oxide as a protective layer to prevent electrodes from corrosion, when applying high voltages (>20 V(pp)) at the electrodes. Then, by exciting the electrodes at high frequency, we capacitively coupled the electrodes to the buffer in order to avoid electric field degradation and, hence, reduction in dielectrophoresis force due to the presence of the insulating oxide layer. To illustrate the functionality of our system, we demonstrated 100% detachment of anti-IgG and IgG bound beads (which is on the same order of magnitude in strength as typical antibody-antigen interactions) from the surface, upon applying the improved negative dielectrophoresis force. The significantly enhanced switching performance presented in this work shows orders of magnitude of improvement in on-to-off ratio and switching response time, without any need for chemical eluting agents, as compared to the previous work. The promising results from this work vindicates that the functionality of this singleplexed platform can be extended to perform a multiplexed bead-based assay where in a single channel an array of proteins are patterned each targeting a different antigen or protein.
PMID: 23176521 [PubMed - indexed for MEDLINE]