bluuebunny/crossref_metadata_2025 huggingface dataset:
High resolution melting analysis for the rapid and sensitive detection of mutations in clinical samples: KRAS codon 12 and 13 mutations in non-small cell lung cancer
Authors: Krypuy Michael , Newnham Genni M , Thomas David M , Conron Matthew , Dobrovic Alexander
Published: December 2006

Background

The development of targeted therapies has created a pressing clinical need for the rapid and robust molecular characterisation of cancers. We describe here the application of high-resolution melting analysis (HRM) to screen for KRAS mutations in clinical cancer samples. In non-small cell lung cancer, KRAS mutations have been shown to identify a group of patients that do not respond to EGFR targeted therapies and the identification of these mutations is thus clinically important.

Methods

We developed a high-resolution melting (HRM) assay to detect somatic mutations in exon 2, notably codons 12 and 13 of the KRAS gene using the intercalating dye SYTO 9. We tested 3 different cell lines with known KRAS mutations and then examined the sensitivity of mutation detection with the cell lines using 189 bp and 92 bp amplicons spanning codons 12 and 13. We then screened for KRAS mutations in 30 non-small cell lung cancer biopsies that had been previously sequenced for mutations in EGFR exons 18–21.

Results

Known KRAS mutations in cell lines (A549, HCT116 and RPMI8226) were readily detectable using HRM. The shorter 92 bp amplicon was more sensitive in detecting mutations than the 189 bp amplicon and was able to reliably detect as little as 5–6% of each cell line DNA diluted in normal DNA. Nine of the 30 non-small cell lung cancer biopsies had KRAS mutations detected by HRM analysis. The results were confirmed by standard sequencing. Mutations in KRAS and EGFR were mutually exclusive.

Conclusion

HRM is a sensitive in-tube methodology to screen for mutations in clinical samples. HRM will enable high-throughput screening of gene mutations to allow appropriate therapeutic choices for patients and accelerate research aimed at identifying novel mutations in human cancer.
Tenofovir treatment augments anti-viral immunity against drug-resistant SIV challenge in chronically infected rhesus macaques
Authors: Metzner Karin J , Binley James M , Gettie Agegnehu , Marx Preston , Nixon Douglas F , Connor Ruth I
Published: December 2006

Background

Emergence of drug-resistant strains of human immunodeficiency virus type 1 (HIV-1) is a major obstacle to successful antiretroviral therapy (ART) in HIV-infected patients. Whether antiviral immunity can augment ART by suppressing replication of drug-resistant HIV-1 in humans is not well understood, but can be explored in non-human primates infected with simian immunodeficiency virus (SIV). Rhesus macaques infected with live, attenuated SIV develop robust SIV-specific immune responses but remain viremic, often at low levels, for periods of months to years, thus providing a model in which to evaluate the contribution of antiviral immunity to drug efficacy. To investigate the extent to which SIV-specific immune responses augment suppression of drug-resistant SIV, rhesus macaques infected with live, attenuated SIVmac239Δnef were treated with the reverse transcriptase (RT) inhibitor tenofovir, and then challenged with pathogenic SIVmac055, which has a five-fold reduced sensitivity to tenofovir.

Results

Replication of SIVmac055 was detected in untreated macaques infected with SIVmac239Δnef, and in tenofovir-treated, naïve control macaques. The majority of macaques infected with SIVmac055 experienced high levels of plasma viremia, rapid CD4+ T cell loss and clinical disease progression. By comparison, macaques infected with SIVmac239Δnef and treated with tenofovir showed no evidence of replicating SIVmac055 in plasma using allele-specific real-time PCR assays with a limit of sensitivity of 50 SIV RNA copies/ml plasma. These animals remained clinically healthy with stable CD4+ T cell counts during three years of follow-up. Both the tenofovir-treated and untreated macaques infected with SIVmac239Δnef had antibody responses to SIV gp130 and p27 antigens and SIV-specific CD8+ T cell responses prior to SIVmac055 challenge, but only those animals receiving concurrent treatment with tenofovir resisted infection with SIVmac055.

Conclusion

These results support the concept that anti-viral immunity acts synergistically with ART to augment drug efficacy by suppressing replication of viral variants with reduced drug sensitivity. Treatment strategies that seek to combine immunotherapeutic intervention as an adjunct to antiretroviral drugs may therefore confer added benefit by controlling replication of HIV-1, and reducing the likelihood of treatment failure due to the emergence of drug-resistant virus, thereby preserving treatment options.
Choroid plexus epithelial monolayers – a cell culture model from porcine brain
Authors: Baehr Carsten , Reichel Valeska , Fricker Gert
Published: December 2006

Background

The goal of the present study was to develop anin vitrochoroid plexus (CP) epithelial cell culture model for studying transport of protein-mediated drug secretion from blood to cerebrospinal fluid (CSF) andvice versa.

Methods

Cells were isolated by mechanical and enzymatic treatment of freshly isolated porcine plexus tissue. Epithelial cell monolayers were grown and CSF secretion and transepithelial resistance were determined. The expression of f-actin as well as the choroid plexus marker protein transthyretin (TTR), were assessed. The expression of the export proteins p-glycoprotein (Pgp, Abcb1) and multidrug resistance protein 1 (Mrp1, Abcc1) was studied by RT-PCR, Western-blot and immunofluorescence techniques and their functional activity was assessed by transport and uptake experiments.

Results

Choroid plexus epithelial cells were isolated in high purity and grown to form confluent monolayers. Filter-grown monolayers displayed transendothelial resistance (TEER) values in the range of 100 to 150 Ωcm2. Morphologically, the cells showed the typical net work of f-actin and expressed TTR at a high rate. The cultured cells were able to secrete CSF at a rate of 48.2 ± 4.6 μl/cm2/h over 2–3 hours. The ABC-export protein Mrp1 was expressed in the basolateral (blood-facing) membranes of cell monolayers and intact tissue. P-glycoprotein showed only low expression within the apical (CSF directed) membrane but was located more in sub-apical cell compartments. This finding was paralleled by the lack of directed excretion of p-glycoprotein substrates, verapamil and rhodamine 123.

Conclusion

It was demonstrated that CP epithelium can be isolated and cultured, with cells growing into intact monolayers, fully differentiating and with properties resembling the tissuein vivo. Thus, the established primary porcine CP model, allowing investigation of complex transport processes, can be used as a reliable tool for analysis of xenobiotic transport across the blood-cerebrospinal fluid barrier (BCSFB).
Animal Model of Schizophrenia
Authors: NABESHIMA TOSHITAKA , MOURI AKIHIRO , MURAI RINA , NODA YUKIHIRO
Published: December 2006

Abstract:  In humans, phencyclidine (PCP), a noncompetitive N‐methyl‐d‐aspartate (NMDA) antagonist, reproduces a schizophrenia‐like psychosis such as positive/negative symptoms and cognitive deficits. PCP (10 mg/kg/day for 14 days)‐treated mice exhibit the enhanced immobility in a forced swimming test as indexes of negative symptoms and impairment of latent learning in a water finding test as indexes of cognitive deficits. These behavioral deficits remain after withdrawal from repeated PCP treatment and are attenuated by atypical antipsychotics, but not by typical antipsychotics. Since it has been hypothesized that insufficient glutamate neurotransmission is involved in the pathophysiology of schizophrenia, we investigated an involvement of glutamatergic system in emotional and cognitive deficits in mice treated with PCP repeatedly. Ca2+/calmodulin kinase II (CaMKII) is markedly phosphorylated after the forced swimming test and the training trial of water finding test in the prefrontal cortex of saline‐treated mice but not PCP‐treated mice. Facilitation of NMDA receptor function by NMDA receptor glycine‐site agonists such as D‐cycloserine and glycine is effective on the abnormal intracellular signaling, and emotional and cognitive deficits in mice treated with PCP repeatedly. The repeated PCP treatment impaired NMDA receptor function and decreased levels of spontaneous extracellular glutamate in the prefrontal cortex, indicating that the repeated PCP treatment impairs both pre‐ and postsynaptic glutamate transmissions. Our findings suggest that abnormal NMDA receptor signaling is involved in the emotional and cognitive deficits in mice treated with PCP repeatedly. Our PCP‐treated mice would be a useful model for studying the effect of antipsychotics on emotional and cognitive deficits in schizophrenia.
LRP in Amyloid‐β Production and Metabolism
Authors: BU GUOJUN , CAM JUDY , ZERBINATTI CELINA
Published: December 2006

Abstract:  Amyloid‐β peptide (Aβ) production and accumulation in the brain is a central event in the pathogenesis of Alzheimer's disease (AD). Recent studies have shown that apolipoprotein E (apoE) receptors, members of the low‐density lipoprotein receptor (LDLR) family, modulate Aβ production as well as Aβ cellular uptake. Aβ is derived from proteolytic processing of the amyloid precursor protein (APP), which interacts with several members of the LDLR family. Studies from our laboratory have focused on two members of the LDLR family, the LDLR‐related protein (LRP) and LRP1B. Our in vitro studies have shown that while LRP's rapid endocytosis facilitates APP endocytic trafficking and processing to Aβ, LRP1B's slow endocytosis inhibits these processes. In addition to modulating APP endocytic trafficking, LRP's rapid endocytosis also facilitates Aβ cellular uptake by binding to Aβ either directly or via LRP ligands such as apoE. Our in vivo studies using transgenic mice have shown that overexpression of LRP in central nervous system (CNS) neurons increases soluble brain Aβ and this increase correlates with deficits in memory. Together our studies demonstrate that members of the LDLR family modulate APP processing and Aβ metabolism by several independent mechanisms. Understanding the pathways that modulate brain Aβ metabolism may enable the rational design of molecular medicine to treat AD.
Involvement of DPPIV/CD26 in Epithelial Morphology and Suppressed Invasive Ability in Ovarian Carcinoma Cells
Authors: KAJIYAMA HIROAKI , SHIBATA KIYOSUMI , TERAUCHI MIKIO , INO KAZUHIKO , NAWA AKIHIRO , KIKKAWA FUMITAKA
Published: December 2006

Abstract:  Dipeptidyl peptidase IV (DPPIV) is a multifunctional cell surface aminopeptidase with ubiquitous expression and it has a variety of functional properties in the development of human malignancies. In the present study, we showed the possible correlation between DPPIV/CD26 expression and less migratory potential with decreased MMP‐2 expression in ovarian carcinoma cells. Moreover, induction of DPPIV/CD26 resulted in reduced expressions of MMP‐2 and mesenchymal markers such as vimentin and SMA, with a less invasive potential and an epithelial morphologic change. This evidence implies that DPPIV/CD26 may play a crucial role in the antimetastatic potential in ovarian carcinoma.
Investigating Gene‐to‐Behavior Pathways in Psychiatric Disorders
Authors: TAKAO KEIZO , MIYAKAWA TSUYOSHI
Published: December 2006

Abstract:  We have been investigating the relationships between genes and behaviors by conducting a systematic and well‐defined behavioral test battery with mice that have a mutation on a gene of interest. The behavioral test battery covers a relatively broad range of various behavioral domains such as learning and memory, sensory‐motor functions, emotion, motivation, and drug sensitivity/preference. Recently, we subjected mice lacking calcineurin (CN), a calcium/calmodulin protein phosphatase, to the comprehensive behavioral test battery. The mutant mice had a severe working memory deficit, increased locomotor activity, decreased social interaction, and impairments in prepulse and latent inhibition. The abnormalities of CN mutant mice were strikingly similar to those described for schizophrenic patients. Consistent with these findings, human genetics studies in a large sample of affected families detected a significant association of the PPP3CC gene, which encodes the CN gamma catalytic subunit with schizophrenia. The idea that abnormalities in the CN signaling pathway are involved in schizophrenia pathogenesis is consistent with traditional theories of schizophrenia and with many facts known about schizophrenia. A tremendous amount of knowledge about CN has accumulated and, by utilizing this information, the studies on the pathogenesis/pathophysiology of schizophrenia and its related mental disorders will be potentially accelerated. We discuss the potential impact of a large‐scale mouse phenotyping project on the study of psychiatric disorders.
The Direct and Indirect Effects of Serofendic Acid on Neuroprotection
Authors: DOI YUKIKO , LIANG JIANFENG , KUNO REIKO , ZANG GUIQIN , KAWANOKUCHI JUN , YAWATA IZUMI , TAKEUCHI HIDEYUKI , MIZUNO TETSUYA , SUZUMURA AKIO
Published: December 2006

Abstract:  Serofendic acid is a novel neuroprotective factor isolated from fetal calf serum. To elucidate the mechanisms how serofendic acid exerts neuroprotection, we examined its effects on glutamate‐induced excito‐toxicity in mouse cortical neurons. The effects of serofendic acid on inflammatory cytokine and neurotrophin production by glial cells were also examined to evaluate the indirect neuroprotection. Serofendic acid significantly and dose dependently increased survival of mouse cortical neurons after 10 μM N‐methyl‐D‐asparate (NMDA) exposure. However, it did not affect production of inflammatory cytokines and neurotrophins by microglia as assessed by reverse transciption polymerase chain reaction (RT‐PCR) for mRNA expression and ELISA for protein levels, though it suppressed tumor necrosis factor (TNF)‐α production by astrocytes. Thus, serofendic acid works directly on neurons to protect against glutamate toxicity. Suppression of TNF‐α production by astoryctes may also synergistically exert neuroprotective functions of serofendic acid. Serofendic acid may be of use for the future therapeutic strategy against ischemic and degenerative neurological disorders.
Gene Expression Profiling toward Understanding of ALS Pathogenesis
Authors: TANAKA FUMIAKI , NIWA JUN‐ICHI , ISHIGAKI SHINSUKE , KATSUNO MASAHISA , WAZA MASAHIRO , YAMAMOTO MASAHIKO , DOYU MANABU , SOBUE GEN
Published: December 2006

Abstract:  Although more than 130 years have gone by since the first description in 1869 by Jean‐Martin Charcot, the mechanism underlying the characteristic selective motor neuron degeneration in amyotrophic lateral sclerosis (ALS) has remained elusive. Modest advances in this research field have been achieved by the identification of copper/zinc superoxide dismutase 1 (SOD1) as one of the causative genes for rare familial ALS (FALS) and by the development and analysis of mutant SOD1 transgenic mouse models. However, in sporadic ALS (SALS) with many more patients, causative or critical genes situated upstream of the disease pathway have not yet been elucidated and no available disease models have been established. To approach genes causative or critical for ALS, gene expression profiling in tissues primarily affected by the disease has represented an attractive research strategy. We have been working on screening these genes employing and combining several new technologies such as cDNA microarray, molecular indexing, and laser capture microdissection. Many of the resultant genes are of intense interest and may provide a powerful tool for determining the molecular mechanisms of ALS. However, we have barely arrived at the starting point and are confronting an enormous number of genes whose roles remain undetermined. Challenging tasks lie ahead of us such as identifying which genes are really causative for ALS and developing a disease model of SALS with due consideration for the expression changes in those genes.
Pharmacogenetic Approach for Cancer Treatment–Tailored Medicine in Practice
Authors: HASEGAWA YOSHINORI , ANDO YUICHI , ANDO MAKI , HASHIMOTO NAOZUMI , IMAIZUMI KAZUYOSHI , SHIMOKATA KAORU
Published: December 2006

Abstract:  This article focuses on pharmacogenetic associations between genetic polymorphism of uridine diphosphate glucuronosyltransferase (UGT) 1A1 gene and irinotecan toxicity. Accumulating evidence provides support to the idea that determination of UGT1A1 polymorphisms before irinotecan treatment is clinically useful and important for predicting and avoiding related toxicities. On the basis of these backgrounds, the irinotecan label was updated in 2005 in the United States to provide pharmacogenetic information, and a dose reduction of irinotecan should be considered for patients known to be homozygous for the UGT1A1*28 allele when administered in combination with other agents or a single agent. The irinotecan/UGT1A1 issue and the development of molecular diagnostic testing are now to be translated into clinical practice.
Functional Single-Nucleotide Polymorphisms in the Secretogranin III (SCG3) Gene that Form Secretory Granules with Appetite-Related Neuropeptides Are Associated with Obesity
Authors: Tanabe Atsushi , Yanagiya Takahiro , Iida Aritoshi , Saito Susumu , Sekine Akihiro , Takahashi Atsushi , Nakamura Takahiro , Tsunoda Tatsuhiko , Kamohara Seika , Nakata Yoshio , Kotani Kazuaki , Komatsu Ryoya , Itoh Naoto , Mineo Ikuo , Wada Jun , Funahashi Tohru , Miyazaki Shigeru , Tokunaga Katsuto , Hamaguchi Kazuyuki , Shimada Tatsuo , Tanaka Kiyoji , Yamada Kentaro , Hanafusa Toshiaki , Oikawa Shinichi , Yoshimatsu Hironobu , Sakata Toshiie , Matsuzawa Yuji , Kamatani Naoyuki , Nakamura Yusuke , Hotta Kikuko
Published: January 2007

Context: Genetic factors are important for the development of obesity. However, the genetic background of obesity still remains unclear.

Objective: Our objective was to search for obesity-related genes using a large number of gene-based single-nucleotide polymorphisms (SNPs).

Design and Setting: We conducted case-control association analyses using 94 obese patients and 658 controls with 62,663 SNPs selected from the SNP database. SNPs that possessed P ≤ 0.02 were further analyzed using 796 obese and 711 control subjects. One SNP (rs3764220) in the secretogranin III (SCG3) gene showed the lowest P value (P = 0.0000019). We sequenced an approximately 300-kb genomic region around rs3764220 and discovered SNPs for haplotype analyses. SCG3 was the only gene within a haplotype block that contained rs3764220. The functions of SCG3 were studied.

Patients: Obese subjects (body mass index ≥ 30 kg/m2, n = 890) and control subjects (general population; n = 658, body mass index ≤ 25kg/m2; n = 711) were recruited for this study.

Results: Twelve SNPs in the SCG3 gene including rs3764220 were in almost complete linkage disequilibrium and significantly associated with an obesity phenotype. Two SNPs (rs16964465, rs16964476) affected the transcriptional activity of SCG3, and subjects with the minor allele seemed to be resistant to obesity (odds ratio, 9.23; 95% confidence interval, 2.77–30.80; χ2 = 19.2; P = 0.0000067). SCG3 mRNA and immunoreactivity were detected in the paraventricular nucleus, lateral hypothalamic area, and arcuate nucleus, and the protein coexisted with orexin, melanin-concentrating hormone, neuropeptide Y, and proopiomelanocortin. SCG3 formed a granule-like structure together with these neuropeptides.

Conclusions: Genetic variations in the SCG3 gene may influence the risk of obesity through possible regulation of hypothalamic neuropeptide secretion.
Inhibition of 11β-Hydroxysteroid Dehydrogenase Type 1 Activity in Vivo Limits Glucocorticoid Exposure to Human Adipose Tissue and Decreases Lipolysis
Authors: Tomlinson Jeremy W. , Sherlock Mark , Hughes Beverley , Hughes Susan V. , Kilvington Fiona , Bartlett William , Courtney Rachel , Rejto Paul , Carley William , Stewart Paul M.
Published: January 2007

Context: The pathophysiological importance of glucocorticoids (GCs) is exemplified by patients with Cushing’s syndrome who develop hypertension, obesity, and insulin resistance. At a cellular level, availability of GCs to the glucocorticoid and mineralocorticoid receptors is controlled by the isoforms of 11β-hydroxysteroid dehydrogenase (11β-HSD). In liver and adipose tissue, 11β-HSD1 converts endogenous, inactive cortisone to active cortisol but also catalyzes the bioactivation of the synthetic prednisone to prednisolone.

Objective: The objective of the study was to compare markers of 11β-HSD1 activity and demonstrate that inhibition of 11β-HSD1 activity limits glucocorticoid availability to adipose tissue.

Design and Setting: This was a clinical study.

Patients: Seven healthy male volunteers participated in the study.

Intervention: Intervention included carbenoxolone (CBX) single dose (100 mg) and 72 hr of continuous treatment (300 mg/d).

Main Outcome Measures: Inhibition of 11β-HSD1 was monitored using five different mechanistic biomarkers (serum cortisol and prednisolone generation, urinary corticosteroid metabolite analysis by gas chromatography/mass spectrometry, and adipose tissue microdialysis examining cortisol generation and glucocorticoid-mediated glycerol release).

Results: Each biomarker demonstrated reduced 11β-HSD1 activity after CBX administration. After both a single dose and 72 hr of treatment with CBX, cortisol and prednisolone generation decreased as did the urinary tetrahydrocortisol+5α-tetrahydrocortisol to tetrahydrocortisone ratio. Using adipose tissue microdialysis, we observed decreased interstitial fluid cortisol availability with CBX treatment. Furthermore, a functional consequence of 11β-HSD1 inhibition was observed, namely decreased prednisone-induced glycerol release into adipose tissue interstitial fluid indicative of inhibition of GC-mediated lipolysis.

Conclusion: CBX is able to inhibit rapidly the generation of active GC in human adipose tissue. Importantly, limiting GC availability in vivo has functional consequences including decreased glycerol release.
Regulation of the arsenic-responsive transcription factor Yap8p involves the ubiquitin-proteasome pathway
Authors: Di Yujun , Tamás Markus J.
Published: January 2007

Toxic metals are ubiquitous in the environment and all organisms possess systems to evade toxicity and acquire tolerance. The Saccharomyces cerevisiae AP-1-like protein Yap8p (systematic name YPR199c; also known as Acr1p and Arr1p) confers arsenic tolerance by stimulating enhanced transcription of the arsenic-specific detoxification genes ACR2 and ACR3. Here, we report that Yap8p is regulated at the level of degradation. We show that Yap8p is stabilized in arsenite-exposed cells in a time- and dose-dependent manner. Yap8p degradation proceeds through the ubiquitin-proteasome pathway and is dependent on the ubiquitin-conjugating enzyme Ubc4p. Further, we show that mutants that are defective in the ubiquitin-proteasome pathway display increased Yap8p levels and elevated expression of the Yap8p gene-target ACR3. Yap8p forms homodimers in vivo but dimerization is not regulated by arsenite. Instead, arsenite-stimulated Yap8p stabilization and transcriptional activation of ACR3 requires critical cysteine residues within Yap8p. Collectively, our data is consistent with a model where Yap8p is degraded by the ubiquitin-proteasome pathway in untreated cells, whereas arsenite-exposure results in Yap8p stabilization and gene activation. In this way, regulated degradation contributes to Yap8p control.
Isoprostane Measurement in Plasma and Urine by Liquid Chromatography–Mass Spectrometry with One-Step Sample Preparation
Authors: Sircar Debajit , Subbaiah Papasani V
Published: January 2007

Background: Isoprostane F2α (iPF2α-III) concentration in plasma and urine is widely accepted as a measure of oxidative stress. Gas chromatography–mass spectrometry (GC/MS) methods for measuring iPF2α-III involve several steps of sample preparation and are labor-intensive, and ELISA methods, although easier to use, are less reliable. Therefore we developed a simple and sensitive method involving 1-step sample cleanup and HPLC/MS quantification.

Methods: Samples of plasma or urine were enriched with a deuterated (iPF2α-III-D4) standard, treated with KOH to liberate the bound isoprostanes, then loaded onto an immunoaffinity column, and the bound isoprostane was eluted with 95% ethanol. The concentrated sample was injected onto a C-18 HPLC column, and the isoprostane was eluted with a gradient of acetonitrile in water and analyzed by electrospray negative ionization, selectively monitoring the ions 353.2 (iPF2α-III) and 357.2 (iPF2α-III-D4). The amount of isoprostane in the sample was calculated from the ratio of the intensities of the 2 ions.

Results: The described method has a detection limit of 0.5 ng/L, with a linear dynamic range of 1–5000 ng/L. The intra- and interassay imprecisions were 4.68% and 3.88%, respectively. The values obtained correlated strongly with the GC/MS procedure (r = 0.80), but the absolute values were ∼4– to 5-fold lower, because the present method measures specifically 1 isomer of isoprostane, whereas the GC/MS method measures 4 isomers together.

Conclusions: Because of its simplicity and lower limit of quantification, the present method provides a useful noninvasive tool for determining oxidative stress in patients.
Biomarkers of Folate and Vitamin B12 Are Related in Blood and Cerebrospinal Fluid
Authors: Obeid Rima , Kostopoulos Panagiotis , Knapp Jean-Pierre , Kasoha Mariz , Becker George , Fassbender Klaus , Herrmann Wolfgang
Published: January 2007

Background: B-vitamins (folate, B12) are important micronutrients for brain function and essential cofactors for homocysteine (HCY) metabolism. Increased HCY has been related to neurological and psychiatric disorders. We studied the role of the B-vitamins in HCY metabolism in the brain.

Methods: We studied blood and cerebrospinal fluid (CSF) samples from 72 patients who underwent lumbar puncture. We measured HCY, methylmalonic acid (MMA), and cystathionine by gas chromatography-mass spectrometry; S-adenosylmethionine (SAM) and S-adenosylhomocysteine (SAH) by liquid chromatography-tandem mass spectrometry; and the B-vitamins by HPLC or immunoassays.

Results: Concentrations were lower in CSF than serum or plasma for HCY (0.09 vs 9.4 μmol/L), SAH (13.2 vs 16.8 nmol/L), cystathionine (54 vs 329 nmol/L), and holotranscobalamin (16 vs 63 pmol/L), whereas concentrations in CSF were higher for MMA (359 vs 186 nmol/L) and SAM (270 vs 113 nmol/L; all P <0.05). CSF concentrations of HCY correlated significantly with CSF folate (r = −0.46), CSF SAH (r = 0.48), CSF-albumin (r = 0.31), and age (r = 0.32). Aging was also associated with lower concentrations of CSF-folate and higher CSF-SAH. The relationship between serum and CSF folate depended on serum folate: the correlation (r) of serum and CSF-folate was 0.69 at serum folate <15.7 nmol/L. CSF concentrations of MMA and holotranscobalamin were not significantly correlated.

Conclusions: CSF and serum/plasma concentrations of vitamin biomarkers are significantly correlated. Older age is associated with higher CSF-HCY and CSF-SAH and lower CSF-folate. These metabolic alterations may be important indicators of low folate status, hyperhomocysteinemia, and neurodegenerative diseases.
Is Supine Rest Necessary before Blood Sampling for Plasma Metanephrines?
Authors: Lenders Jacques WM , Willemsen Jacques J , Eisenhofer Graeme , Ross H Alec , Pacak Karel , Timmers Henri JLM , Sweep CGJ (Fred)
Published: January 2007

Background: The impact of blood sampling in sitting vs supine positions on measurements of plasma metanephrines for diagnosis of pheochromocytoma is unknown.

Methods: We compared plasma concentrations of free metanephrines in samples from patients with primary hypertension obtained after supine rest with those obtained in the sitting position without preceding rest. We also assessed the effects on diagnostic test performance retrospectively in patients with and without pheochromocytoma, and we calculated cost-effectiveness for pheochromocytoma testing.

Results: Upper reference limits of plasma free metanephrines were higher in samples obtained from seated patients without preceding rest than from supine patients with preceding rest. Application of these higher upper reference limits to samples from supine patients with pheochromocytoma decreased the diagnostic sensitivity from 99% to 96%. In patients without pheochromocytoma, adjusting the plasma concentration for the effects of sitting while preserving the 99% sensitivity by use of the supine upper reference limits increased the number of false-positive test results from 9% to 25%.

Conclusions: To preserve high diagnostic sensitivity we recommend the use of upper reference limits determined from blood samples collected in the supine position. Under these conditions, negative test results for blood samples obtained with patients sitting are as effective for ruling out pheochromocytoma as negative results from samples obtained after supine rest. Repeat testing with samples obtained in the supine position offers a cost-effective approach for dealing with the increased numbers of false-positive results expected after initial sampling in the sitting position.
Community-orientierte Dienste für digitales interaktives Fernsehen: Das Beispiel der „Find-a-Friend”-Anwendung (Community Based Services for Digital Interactive Television: The „Find-a-Friend” Prototype)
Authors: Heß Jan , Wulf Volker
Published: December 2006

Die Digitalisierung des Fernsehens bildet die Grundlage für neue interaktive Dienste. Die veränderten technischen Rahmenbedingungen ermöglichen neue Formen von Kommunikationsanwendungen. So können On-Demand Dienste (Individualkommunikation) die TV-Rezeption (Massenkommunikation) ergänzen. Die entwickelte Anwendung „Find-a-Friend” ermöglicht die Ausbildung von sozialen Kontakten in lokalen Gemeinschaften von Fernsehzuschauern. Innerhalb eines Postleitzahlbereiches können Zuschauer untereinander Textnachrichten austauschen, die als Programmüberblendung angezeigt werden.
Geogames – Ortsbezogene Spiele als neue Form des Edutainment (Geogames – Location-based Games as a Novel Type of Edutainment)
Authors: Schlieder Christoph , Kiefer Peter , Matyas Sebastian
Published: December 2006

Ortsbezogene Spiele nutzen die durch Lokalisierungstechnologien wie GPS aufgezeichnete Fortbewegung der Spieler als zentrale Form der Interaktion mit der auf mobilen Endgeräten implementierten Spiellogik. Dieser Artikel beschreibt den Geogames-Ansatz, der es ermöglicht, strategische Elemente aus herkömmlichen Brettspielen mit ortsbezogenen Spielkonzepten zu kombinieren. Ein Beispiel ist das Spiel GeoTicTacToe. Wir zeigen, dass bei jedem Geogame die Spielereignisse durch Auszeiten synchronisiert werden müssen. Diese Auszeiten eignen sich hervorragend zur Einbettung von Edutainmentinhalten. Anhand eines Testspiels wird vorgeführt, wie der Geogame-Ansatz bei Vermittlung des UNESCO-Weltkulturerbegedankens in der Altstadt von Bamberg umgesetzt wurde.
On Markovian short rates in term structure models driven by jump-diffusion processes
Authors: Gapeev Pavel V. , Küchler Uwe
Published: December 2006

In this paper a bond market model and the related term structure of interest rates are studied where prices of zero coupon bonds are driven by a jump-diffusion process. A criterion is derived on the deterministic forward rate volatilities underwhich the short rate process isMarkovian. In the case that the volatilities depend on the short rate sufficient conditions are presented for the existence of a finite-dimensional Markovian realization of the term structure model.
Unsolvated ruthenium(II) benzene dichloride: a structural comparison with the chloroform solvate
Authors: Sevryugina Yulia , Petrukhina Marina A.
Published: December 2006

The crystal structure of the unsolvated ruthenium(II) benzene dichloride, [RuCl2(η
6-C6H6)]2, has been determined by X-ray crystallography. The title complex shows features unique among the series of [RuCl2(η
6-arene)]2 compounds, such as non-parallel alignment of the benzene rings and non-planarity of the central tetranuclear core comprised of two ruthenium atoms and two bridging chlorides. A detailed structural comparison with the previously reported solvated analogue revealed a similarity in the bonding distances but differences in bonding angles and packing arrangements.
In-Situ-ATR-FTIR Detection of Protein Sorption at Polyelectrolyte Multilayers: Variation of the Thickness
Authors: Müller M. , Keßler B. , Ouyang W.
Published: December 2006

In-situ ATR FTIR spectroscopy was used to study protein adsorption at polyelectrolyte multilayers (PEM). PEM were fabricated by consecutively adsorbing poly(ethyleneimine) (PEI) and poly(acrylic acid) (PAC) analogously to the technique introduced by Decher at silicon internal reflection elements in an in-situ ATR cell. The thickness of PEM of PEI/PAC could be varied by pH value, concentration and number of adsorption steps. At this PEM system adsorption of human serum albumin was studied under electrostatically attractive conditions in dependence of the thickness. Evidence was found, that HSA was predominantly bound in the uncompensated outermost layer region rather than in the bulk phase of the PEM.
Hydrogen Bonding of Water Confined in Controlled-Pore Glass 10-75 Studied by 1H-Solid State NMR
Authors: Vyalikh A. , Emmler Th. , Grünberg B. , Xu Y. , Shenderovich I. , Findenegg G. H. , Limbach H.-H. , Buntkowsky G.
Published: December 2006

The adsorption of water in the mesoporous silica material with cylindrical pores of uniform diameter, Controlled Pore Glass 10-75 (CPG), was studied by 1H-MAS solid state NMR spectroscopy. From the NMR spectra it is evident that inside the mesopores of the silica different water environments exist, which are characterized by their individual chemical shift. All observed hydrogen atoms are either surface –SiOH groups or hydrogen bonded water molecules. It is found that there exist some stronger bound water molecules on the surface which are not removable even by heating at a vacuum pump. As a tentative assignment these water molecules are attributed to surface defects or inaccessible cavities in the CPG 10-75. At intermediate water filling levels, the principal signal is a single NMR line with continuously varying chemical shift. This finding is interpreted as the result of a radial water filling mechanism. That is, the filling of the pore grows from the pore surface towards the pore axis. Finally it is shown that water is a sensor for surface and structural inhomogeneity and that a coexistence of inner pore and outer bulk water exists in the system.
Surface-Tethered Polymers to Influence Protein Adsorption and Microbial Adhesion
Authors: Norde Willem
Published: December 2006

In various applications it is desired that biological cells or protein molecules are immobilized at surfaces. Examples are enzymes or cells in bioreactors and biosensors, immuno-proteins in solid-state diagnostics and proteinaceous farmacons in drug delivery systems. In order to retain biological activity, the structural integrity of the immobilized bio-compounds should be preserved. In other cases immobilization of cells and proteins should be avoided. Adsorption of proteins from biofluids is considered to be the first event in the biofouling process. Subsequently, bacterial and/or other biological cells (e.g., blood platelets, erythrocytes) deposit on the adsorbed protein layer and a biofilm is formed. This causes great problems in areas as diverse as biomedicine, food processing and the marine environment. A generic approach to influence the magnitude of the interaction between a particle (e.g., a cell or a globular protein molecule) and a sorbent material is to manipulate both the long- and short-range interaction forces by grafting soluble polymers or oligomers onto the sorbent surface. Application of oligomers of ethylene oxide (EO) prevents the particles from making intimate contact with the surface. Thus, adsorbed enzymes may retain their native structure and, hence, their enzymatic activity. Another interesting example is the steering effect of pre-adsorbed polymers of EO (PEO) on the orientation of subsequently depositing anisotropic particles. For instance, IgG molecules may be forced in the right orientation and conformation in the interstitial spaces between the PEO chains, therewith doubling the specific antigen binding capacity. By far the greatest part of recent research on modifying surfaces by grafting soluble polymers (usually PEO) aims at the prevention of protein adsorption and/or adhesion of biological cells. Suppression of particle deposition depends primarily on two characteristics of the polymer layer: (a) the grafting density, and (b) the extension of the polymer layer into the solution. The efficacy of grafted PEO layers to reduce protein adsorption and microbial adhesion is illustrated for blood plasma proteins, saliva proteins and a number of bacterial and yeast cells.
Ultrasensitive Fluorescence Microscopy Studies of Protein Interactions with Functionalized Surfaces
Authors: Heyes Colin D. , Nienhaus G. Ulrich
Published: December 2006

Controlling protein adsorption to surfaces is an important issue in biotechnology, biomedicine and basic sciences. Proteins readily adsorb non-specifically to a variety of surfaces in a process known as biofouling, which is a major problem in the biomedical, environmental and industrial fields that can be solved by pre-treating the surfaces with adsorption-resistant materials. Additionally, surfaces can be structured and functionalized so as to immobilize proteins in specific patterns, orientations and/or densities, which is important in such areas as biosensors, biocatalysis, biotechnology, protein microarrays and single molecule biophysics. Here we review the various surface modifications and bioconjugation techniques that have been used in these areas. We also introduce novel fluorescence microscopy techniques, which have been employed to analyze the resistance of the surfaces to non-specific adsorption with detection limits down to the single molecule. A huge advantageous property of fluorescence microscopy is its sensitivity to the structure of individual, immobilized proteins by using Förster resonance energy transfer (FRET). Thus one can examine if the surface coating maintains the folded, functional form of specifically immobilized proteins. We then describe several important advances in studying slow timescale biophysical processes such as protein folding of single, specifically immobilized proteins. Future directions into which this field is expected to progress are also discussed.
A National Assessment of Knowledge, Attitudes, and Confidence of Prehospital Providers in the Assessment and Management of Child Maltreatment
Authors: Markenson David , Tunik Michael , Cooper Arthur , Olson Lenora , Cook Lawrence , Matza-Haughton Hedda , Treiber Marsha , Brown William , Dickinson Phil , Foltin George
Published: January 2007

OBJECTIVE. The goal was to assess the knowledge and confidence in recognition, management, documentation, and reporting of child maltreatment among a representative sample of emergency medical services personnel in the United States.

METHODS. A questionnaire was developed and pilot-tested, with the input of experts in emergency medical services and child maltreatment, to assess knowledge, attitudes, confidence, and training needs regarding assessment and treatment of child maltreatment. The questionnaire was distributed nationally to a random sample of prehospital providers by using a previously validated sampling plan.

RESULTS. Of 2863 surveys sent to prehospital providers, 1237 (43%) were returned. Most prehospital providers reported receiving ≤1 hour of continuing medical education regarding child maltreatment. Most (78%) asked for additional educational opportunities, with only 3% stating that they required no additional training. Participants lacked knowledge regarding the developmental abilities of children, management of families in which child maltreatment is suspected, key elements of the history that should be noted, and the degree of suspicion necessary for reporting.

CONCLUSIONS. Prehospital providers expressed confidence in their abilities to recognize and to manage cases of child abuse and neglect; however, significant deficiencies were reported in several critical knowledge areas, including identification of child maltreatment, interviewing techniques, and appropriate documentation.
Pediatrician Characteristics Associated With Attention to Spirituality and Religion in Clinical Practice
Authors: Grossoehme Daniel H. , Ragsdale Judith R. , McHenry Christine L. , Thurston Celia , DeWitt Thomas , VandeCreek Larry
Published: January 2007

OBJECTIVE. The literature suggests that a majority of pediatricians believe that spirituality and religion are relevant in clinical practice, but only a minority gives them attention. This project explored this disparity by relating personal/professional characteristics of pediatricians to the frequency with which they give attention to spirituality and religion.

METHODS. Pediatricians (N = 737) associated with 3 academic Midwestern pediatric hospitals responded to a survey that requested information concerning the frequency with which they (1) talked with patients/families about their spiritual and religious concerns and (2) participated with them in spiritual or religious practices (eg, prayer). The associations between these data and 10 personal and professional characteristics were examined.

RESULTS. The results demonstrated the disparity, and the analysis identified 9 pediatrician characteristics that were significantly associated with more frequently talking with patients/families about their spiritual and religious concerns. The characteristics included increased age; a Christian religious heritage; self-description as religious; self-description as spiritual; the importance of one's own spirituality and religion in clinical practice; the belief that the spirituality and religion of patients/families are relevant in clinical practice; formal instruction concerning the role of spirituality and religion in health care; relative comfort asking about beliefs; and relative comfort asking about practices. All of these characteristics except pediatrician age were also significantly associated with the increased frequency of participation in spiritual and religious practices with patients/families.

CONCLUSIONS. Attention to spiritual and religious concerns and practices are associated with a web of personal and professional pediatrician characteristics. Some characteristics pertain to the physician's personal investment in spirituality and religion in their own lives, and others include being uncomfortable with spiritual and religious concerns and practices. These associations shed light on the disparity between acknowledged spirituality and religion relevancy and inattention to it in clinical practice.
First Report of Autologous Cord Blood Transplantation in the Treatment of a Child With Leukemia
Authors: Hayani Ammar , Lampeter Eberhard , Viswanatha David , Morgan David , Salvi Sharad N.
Published: January 2007

We present the case of a 3-year-old girl with acute lymphoblastic leukemia who developed isolated central nervous system relapse while receiving chemotherapy 10 months after diagnosis. The child achieved a second remission on retreatment with systemic and intrathecal chemotherapy. She then underwent myeloablative chemotherapy and radiation therapy followed by infusion of her own umbilical cord blood, which the parents had saved after her delivery. She is now doing well and is in complete remission 20 months after cord blood transplantation. In this first report of autologous cord blood transplantation for treatment of childhood leukemia, we discuss the safety and feasibility of this procedure as well as some of the uncertainties surrounding autologous cord blood collection and usage.
Infection in the First 2 Years of Life and Autism Spectrum Disorders
Authors: Rosen Nila J. , Yoshida Cathleen K. , Croen Lisa A.
Published: January 2007

OBJECTIVE. The purpose of this work was to investigate the association between infections in the first 2 years and subsequent diagnosis of autism spectrum disorders.

METHODS. We conducted a case-control study among children born at Kaiser Permanente Northern California from 1995 to 1999. Case subjects (n = 403) were children with an autism diagnosis recorded in Kaiser Permanente databases. Control subjects (n = 2100) were randomly sampled from the remaining children without autism and frequency matched to case subjects on gender, birth year, and birth hospital. Information on infections and covariates were obtained from Kaiser Permanente and birth certificate databases.

RESULTS. Overall, infection diagnoses in the first 2 years of life were recorded slightly less often for children with autism than control children (95.0% vs 97.5%). Among specific diagnoses, upper respiratory infections were significantly less frequently diagnosed and genitourinary infections more frequently diagnosed in children with autism. In the first 30 days of life, the frequency of having an infection was slightly higher among children with autism (22.6% vs 18.7%).

CONCLUSIONS. Children with subsequent diagnoses of autism do not have more overall infections in the first 2 years of life than children without autism. Data suggest that children with autism may have modestly elevated rates of infection in the first 30 days and that, during the first 2 years, children with autism may be at higher risk for certain types of infections and lower risk for others. Additional studies that explore the associations between prenatal and early childhood infections and autism may help clarify the role of infection and the immune system in the etiology of autism spectrum disorder.
Effects of Selective Serotonin Reuptake Inhibitors and Venlafaxine During Pregnancy in Term and Preterm Neonates
Authors: Ferreira Ema , Carceller Ana Maria , Agogué Claire , Martin Brigitte Zoé , St-André Martin , Francoeur Diane , Bérard Anick
Published: January 2007

OBJECTIVES. Our goals were to (a) describe neonatal behavioral signs in a group of newborns exposed in utero to selective serotonin reuptake inhibitors or venlafaxine at the time of delivery, (b) compare the rate of neonatal behavioral signs, prematurity, and admission to specialized neonatal care between a group of exposed and unexposed newborns, and (c) compare the effects in exposed preterm and term newborns.

PATIENTS AND METHODS. This was a retrospective cohort study including mothers taking selective serotonin reuptake inhibitors or venlafaxine during the third trimester and mothers who were not taking any antidepressants, psychotropic agents, or benzodiazepines at the time of delivery of their newborns. Neonatal behavioral signs included central nervous, respiratory, and digestive systems, as well as hypoglycemia and the need for phototherapy.

RESULTS. Seventy-six mothers taking antidepressants and 90 untreated mothers and their newborns were analyzed. Smoking, alcohol intake, and substance abuse were more frequent among treated mothers. In infants in the exposed group, signs involving the central nervous and the respiratory systems were often observed (63.2% and 40.8%, respectively). These signs appeared during the first day of life, with a median duration of 3 days for exposed newborns. The signs resolved in 75% of cases within 3 to 5 days for term and premature newborns, respectively. All exposed premature newborns presented behavioral manifestations compared with 69.1% of term exposed newborns. Median length of stay was almost 4 times longer for exposed premature newborns than for those who were unexposed (14.5 vs 3.7 days).

CONCLUSIONS. Neonatal behavioral signs were frequently found in exposed newborns, but symptoms were transient and self-limited. Premature infants could be more susceptible to the effects of selective serotonin reuptake inhibitors and venlafaxine.