Real-time PCR-based assay to quantify the relative amount of human and mouse tissue present in tumor xenografts

<p>Abstract</p> <p>Background</p> <p>Xenograft samples used to test anti-cancer drug efficacies and toxicities in vivo contain an unknown mix of mouse and human cells. Evaluation of drug activity can be confounded by samples containing large amounts of contaminating mouse tissue. We have developed a real-time quantitative polymerase chain reaction (qPCR) assay using TaqMan technology to quantify the amount of mouse tissue that is incorporated into human xenograft samples.</p> <p>Results</p> <p>The forward and reverse primers bind to the same DNA sequence in the human and the mouse genome. Using a set of specially designed fluorescent probes provides species specificity. The linearity and sensitivity of the assay is evaluated using serial dilutions of single species and heterogeneous DNA mixtures. We examined many xenograft samples at various in vivo passages, finding a wide variety of human:mouse DNA ratios. This variation may be influenced by tumor type, number of serial passages in vivo, and even which part of the tumor was collected and used in the assay.</p> <p>Conclusions</p> <p>This novel assay provides an accurate quantitative assessment of human and mouse content in xenograft tumors. This assay can be performed on aberrantly behaving human xenografts, samples used in bioinformatics studies, and periodically for tumor tissue frequently grown by serial passage in vivo.</p

Perception of Shadows in Children with Autism Spectrum Disorders

Background: Cast shadows in visual scenes can have profound effects on visual perception. Much as they are informative, they also constitute noise as they are salient features of the visual scene potentially interfering with the processing of other features. Here we asked i) whether individuals with autism can exploit the information conveyed by cast shadows; ii) whether they are especially sensitive to noise aspects of shadows. Methodology/Principal Findings: Twenty high-functioning children with autism and twenty typically developing children were asked to recognize familiar objects while the presence, position, and shape of the cast shadow were systematically manipulated. Analysis of vocal reaction time revealed that whereas typically developing children used information from cast shadows to improve object recognition, in autistic children the presence of cast shadows—either congruent or incongruent—interfered with object recognition. Critically, vocal reaction times were faster when the object was presented without a cast shadow. Conclusions/Significance: We conclude that shadow-processing mechanisms are abnormal in autism. As a result, processing shadows becomes costly and cast shadows interfere rather than help object recognition

Joint sequencing of human and pathogen genomes reveals the genetics of pneumococcal meningitis.

Streptococcus pneumoniae is a common nasopharyngeal colonizer, but can also cause life-threatening invasive diseases such as empyema, bacteremia and meningitis. Genetic variation of host and pathogen is known to play a role in invasive pneumococcal disease, though to what extent is unknown. In a genome-wide association study of human and pathogen we show that human variation explains almost half of variation in susceptibility to pneumococcal meningitis and one-third of variation in severity, identifying variants in CCDC33 associated with susceptibility. Pneumococcal genetic variation explains a large amount of invasive potential (70%), but has no effect on severity. Serotype alone is insufficient to explain invasiveness, suggesting other pneumococcal factors are involved in progression to invasive disease. We identify pneumococcal genes involved in invasiveness including pspC and zmpD, and perform a human-bacteria interaction analysis. These genes are potential candidates for the development of more broadly-acting pneumococcal vaccines

Endothelial Function: The Impact of Objective and Subjective Socioeconomic Status on Flow-Mediated Dilation

Although objective and subjective indicators of socioeconomic status (SES) are linked to cardiovascular disease (CVD), little is known about their relationship to endothelial dysfunction, which often precedes CVD. This study examined how objective and subjective SES relate to brachial artery flow-mediated dilation (FMD). FMD was assessed in 72 healthy adults (mean age 36 years). The MacArthur Scale of Subjective Social Status assessed perceived social standing in the USA (SSS-USA) and local community (SSS-Community). Objective SES measures included income and the Hollingshead Two-Factor Index of Social Position (education, occupation). Adjusted regressions revealed that SSS-Community positively correlated with FMD (p &lt; 0.05) and explained 8% of the variance. No other SES measures were significant for FMD. The association between FMD and SSS-Community remained significant (p &lt; 0.01) after adjustment for objective SES and other covariates. Lower subjective social status in one’s community may be linked to CVD via impaired vasodilation

Genetic Architecture of Hybrid Male Sterility in Drosophila: Analysis of Intraspecies Variation for Interspecies Isolation

Background: The genetic basis of postzygotic isolation is a central puzzle in evolutionary biology. Evolutionary forces causing hybrid sterility or inviability act on the responsible genes while they still are polymorphic, thus we have to study these traits as they arise, before isolation is complete. Methodology/Principal Findings: Isofemale strains of D. mojavensis vary significantly in their production of sterile F 1 sons when females are crossed to D. arizonae males. We took advantage of the intraspecific polymorphism, in a novel design, to perform quantitative trait locus (QTL) mapping analyses directly on F1 hybrid male sterility itself. We found that the genetic architecture of the polymorphism for hybrid male sterility (HMS) in the F1 is complex, involving multiple QTL, epistasis, and cytoplasmic effects. Conclusions/Significance: The role of extensive intraspecific polymorphism, multiple QTL, and epistatic interactions in HMS in this young species pair shows that HMS is arising as a complex trait in this system. Directional selection alone would be unlikely to maintain polymorphism at multiple loci, thus we hypothesize that directional selection is unlikely to be the only evolutionary force influencing postzygotic isolation

Association between Catechol-O-Methyltrasferase Val108/158Met Genotype and Prefrontal Hemodynamic Response in Schizophrenia

BACKGROUND:"Imaging genetics" studies have shown that brain function by neuroimaging is a sensitive intermediate phenotype that bridges the gap between genes and psychiatric conditions. Although the evidence of association between functional val108/158met polymorphism of the catechol-O-methyltransferase gene (COMT) and increasing risk for developing schizophrenia from genetic association studies remains to be elucidated, one of the most topical findings from imaging genetics studies is the association between COMT genotype and prefrontal function in schizophrenia. The next important step in the translational approach is to establish a useful neuroimaging tool in clinical settings that is sensitive to COMT variation, so that the clinician could use the index to predict clinical response such as improvement in cognitive dysfunction by medication. Here, we investigated spatiotemporal characteristics of the association between prefrontal hemodynamic activation and the COMT genotype using a noninvasive neuroimaging technique, near-infrared spectroscopy (NIRS). METHODOLOGY/PRINCIPAL FINDINGS:Study participants included 45 patients with schizophrenia and 60 healthy controls matched for age and gender. Signals that are assumed to reflect regional cerebral blood volume were monitored over prefrontal regions from 52-channel NIRS and compared between two COMT genotype subgroups (Met carriers and Val/Val individuals) matched for age, gender, premorbid IQ, and task performance. The [oxy-Hb] increase in the Met carriers during the verbal fluency task was significantly greater than that in the Val/Val individuals in the frontopolar prefrontal cortex of patients with schizophrenia, although neither medication nor clinical symptoms differed significantly between the two subgroups. These differences were not found to be significant in healthy controls. CONCLUSIONS/SIGNIFICANCE:These data suggest that the prefrontal NIRS signals can noninvasively detect the impact of COMT variation in patients with schizophrenia. NIRS may be a promising candidate translational approach in psychiatric neuroimaging

Classification of First-Episode Schizophrenia Patients and Healthy Subjects by Automated MRI Measures of Regional Brain Volume and Cortical Thickness

BACKGROUND: Although structural magnetic resonance imaging (MRI) studies have repeatedly demonstrated regional brain structural abnormalities in patients with schizophrenia, relatively few MRI-based studies have attempted to distinguish between patients with first-episode schizophrenia and healthy controls. METHOD: Three-dimensional MR images were acquired from 52 (29 males, 23 females) first-episode schizophrenia patients and 40 (22 males, 18 females) healthy subjects. Multiple brain measures (regional brain volume and cortical thickness) were calculated by a fully automated procedure and were used for group comparison and classification by linear discriminant function analysis. RESULTS: Schizophrenia patients showed gray matter volume reductions and cortical thinning in various brain regions predominantly in prefrontal and temporal cortices compared with controls. The classifiers obtained from 66 subjects of the first group successfully assigned 26 subjects of the second group with accuracy above 80%. CONCLUSION: Our results showed that combinations of automated brain measures successfully differentiated first-episode schizophrenia patients from healthy controls. Such neuroimaging approaches may provide objective biological information adjunct to clinical diagnosis of early schizophrenia

Health related quality of life measure in systemic pediatric rheumatic diseases and its translation to different languages: an international collaboration

Background: Rheumatic diseases in children are associated with significant morbidity and poor health-related quality of life (HRQOL). There is no health-related quality of life (HRQOL) scale available specifically for children with less common rheumatic diseases. These diseases share several features with systemic lupus erythematosus (SLE) such as their chronic episodic nature, multi-systemic involvement, and the need for immunosuppressive medications. HRQOL scale developed for pediatric SLE will likely be applicable to children with systemic inflammatory diseases.Findings: We adapted Simple Measure of Impact of Lupus Erythematosus in Youngsters (SMILEY (c)) to Simple Measure of Impact of Illness in Youngsters (SMILY (c)-Illness) and had it reviewed by pediatric rheumatologists for its appropriateness and cultural suitability. We tested SMILY (c)-Illness in patients with inflammatory rheumatic diseases and then translated it into 28 languages. Nineteen children (79% female, n= 15) and 17 parents participated. the mean age was 12 +/- 4 years, with median disease duration of 21 months (1-172 months). We translated SMILY (c)-Illness into the following 28 languages: Danish, Dutch, French (France), English (UK), German (Germany), German (Austria), German (Switzerland), Hebrew, Italian, Portuguese (Brazil), Slovene, Spanish (USA and Puerto Rico), Spanish (Spain), Spanish (Argentina), Spanish (Mexico), Spanish (Venezuela), Turkish, Afrikaans, Arabic (Saudi Arabia), Arabic (Egypt), Czech, Greek, Hindi, Hungarian, Japanese, Romanian, Serbian and Xhosa.Conclusion: SMILY (c)-Illness is a brief, easy to administer and score HRQOL scale for children with systemic rheumatic diseases. It is suitable for use across different age groups and literacy levels. SMILY (c)-Illness with its available translations may be used as useful adjuncts to clinical practice and research.Rutgers State Univ, Robert Wood Johnson Med Sch, New Brunswick, NJ 08903 USARutgers State Univ, Child Hlth Inst New Jersey, New Brunswick, NJ 08901 USAHosp Special Surg, New York, NY 10021 USAUniv Michigan, Ann Arbor, MI 48109 USARed Cross War Mem Childrens Hosp, Cape Town, South AfricaAin Shams Univ, Pediat Allergy Immunol & Rheumatol Unit, Cairo, EgyptAin Shams Univ, Pediat Rheumatol Pediat Allergy Immunol & Rheum, Cairo, EgyptKing Faisal Specialist Hosp & Res Ctr, Riyadh 11211, Saudi ArabiaCharles Univ Prague, Prague, Czech RepublicGen Univ Hosp, Prague, Czech RepublicUniv Hosp Motol, Dept Pediat, Prague, Czech RepublicAarhus Univ, Hosp Skejby, Aarhus, DenmarkRigshosp, Juliane Marie Ctr, DK-2100 Copenhagen, DenmarkUniv Med Ctr, Dept Pediat Immunol, Utrecht, NetherlandsWilhelmina Childrens Hosp, Utrecht, NetherlandsGreat Ormond St Hosp Sick Children, Children NHS Fdn Trust, Renal Unit, London, EnglandLyon Univ, Hosp Civils Lyon, Rheumatol & Dermatol Dept, Lyon, FranceMed Univ Innsbruck, A-6020 Innsbruck, AustriaPrim Univ Doz, Bregenz, AustriaHamburg Ctr Pediat & Adolescence Rheumatol, Hamburg, GermanyAsklepios Clin Sankt, Augustin, GermanyUniv Zurich, Childrens Hosp, Zurich, SwitzerlandAristotle Univ Thessaloniki, Pediat Immunol & Rheumatol Referral Ctr, GR-54006 Thessaloniki, GreeceIsrael Meir Hosp, Kefar Sava, IsraelSanjay Gandhi Postgrad Inst Med Sci, Lucknow, Uttar Pradesh, IndiaSemmelweis Univ, H-1085 Budapest, HungaryAnna Meyer Hosp, Florence, ItalyUniv Siena, Res Ctr System Autoimmune & Autoinflammatory Dis, I-53100 Siena, ItalyUniv Florence, Florence, ItalyOsped Pediat Bambino Gesu, IRCCS, Pediat Rheumatol Unit, Rome, ItalyUniv Genoa Pediat II Reumatol, Ist G Gaslini EULAR, Ctr Excellence Rheumatol, Genoa, ItalyUniv Cattolica Sacro Cuore, Inst Pediat, Rome, ItalyUniv Padua, Dept Pediat, Pediat Rheumatol Unit, Padua, ItalyYokohama City Univ, Sch Med, Yokohama, Kanagawa 232, JapanUniv Estadual Paulista, UNESP, Botucatu, SP, BrazilUniversidade Federal de São Paulo, Dept Pediat, São Paulo, BrazilUniv Estadual Campinas, Dept Med, Campinas, SP, BrazilUniv Fed Rio de Janeiro, Dept Pediat, Rio de Janeiro, BrazilUniv Estado do, Adolescent Hlth Care Unit, Div Pediat Rheumatol, Rio de Janeiro, BrazilUniv São Paulo, Fac Med, Childrens Inst, Dept Pediat,Pediat Rheumatol Unit, São Paulo, BrazilChildrens Inst, Pediat Rheumatol Unit, São Paulo, BrazilClin Pediat I, Cluj Napoca, RomaniaInst Rheumatol, Belgrade, SerbiaUniv Childrens Hosp, Univ Med Ctr Ljubljana, Ljubljana, SloveniaHead Rheumatol Hosp Pedro Elizalde, Buenos Aires, DF, ArgentinaHosp Gen Mexico City, Mexico City, DF, MexicoHosp Infantil Mexico Fed Gomez, Mexico City, DF, MexicoHosp San Juan Dios, Barcelona, SpainHosp Univ Valle Hebron, Barcelona, SpainMt Sinai Med Ctr, New York, NY 10029 USAMt Sinai Med Ctr, Miami Beach, FL 33140 USAComplejo Hosp Univ Ruiz & Paez, Bolivar, VenezuelaHacettepe Univ, Dept Pediat, Ankara, TurkeyIstanbul Univ, Cerrahpasa Med Sch, Istanbul, TurkeyFMF Arthrit Vasculitis & Orphan Dis Res Ctr, Inst Hlth Sci, Ankara, TurkeyUniv Calgary, Dept Pediat, Alberta Childrens Hosp, Res Inst, Calgary, AB T2N 1N4, CanadaUniversidade Federal de São Paulo, Dept Pediat, São Paulo, BrazilWeb of Scienc