bluuebunny/crossref_metadata_2025 huggingface dataset:
The impact of positron emission tomography (PET) on expected management during cancer treatment
Authors: Hillner Bruce E. , Siegel Barry A. , Shields Anthony F. , Liu Dawei , Gareen Ilana F. , Hanna Lucy , Stine Sharon Hartson , Coleman R. Edward
Published: November 2008

BACKGROUND:

Positron emission tomography (PET) performed during cancer therapy (treatment monitoring) has shown promise for predicting treatment outcome. However, when used for this purpose, PET generally is not considered standard care. Under the Medicare ‘coverage with evidence development’ policy, PET (and integrated PET/computed tomography) became a covered service for treatment monitoring if prospective registry data were collected.

METHODS:

The National Oncologic PET Registry collected questionnaire data on intended patient management before and after PET. Data were available from 8240 patients who had 10,497 treatment‐monitoring PET scans at 946 centers; these studies were used to monitor chemotherapy alone (82%), radiation therapy alone (6%), or combined‐modality treatment (12%). Ovarian, pancreatic, and lung cancers accounted for 37% of the cohort. In 54% of scans, the pre‐PET summary stage was metastatic disease.

RESULTS:

If PET had not been available, then the pre‐PET plan would have been other imaging (53%), ongoing treatment (41%), or biopsy or watching (6%). Change in the post‐PET intended management was similar in the imaging and treatment groups: 26% to 28% of scans to switching to another therapy, and 16% to 19% scans led to adjustment of the dose or duration of therapy. Changes in management were more frequent if the referring physician judged that the post‐PET prognosis was worse rather than improved or unchanged (78% vs 40%). The physicians indicated that PET enabled 91% of their patients to avoid future tests.

CONCLUSIONS:

Physicians often report plans to modify their therapeutic plans in elderly cancer patients when PET is used for treatment monitoring. Cancer 2009. © 2009 American Cancer Society.
Intrinsic Volumetric Properties of Trialanine Isomers in Aqueous Solution
Authors: Mitra Lally , Oleinikova Alla , Winter Roland
Published: November 2008

The intrinsic volume and the intrinsic coefficient of thermal expansion of alanine tripeptides of different chirality are obtained from densimetric and pressure‐perturbation calorimetric measurements by using the volumetric properties of water of hydration obtained from computer simulations. The aim of this study is to provide better understanding of the different contributions to the volumetric properties of peptides in solution. Water of hydration makes a major contribution to the volumetric properties measured experimentally. The intrinsic thermal expansivity of the peptides is found to be negative despite positive apparent values of thermal expansivity due to the large positive expansivity of the water of hydration, which notably exceeds the bulk value. The different volumetric behavior of the isomers is discussed in relation to their structural characteristics.
Design and implementation of a digital control IC for driving multiple cold cathode fluorescent lamps
Authors: Shin Haw‐Yun , Yang Jui‐Piao
Published: November 2008

This study designs and develops a digital control integrated circuit (IC) for driving circuits operating multiple cold cathode fluorescent lamps (CCFLs). The control IC adopts an external crystal oscillator for the IC's external frequency to provide the driving circuits a fixed frequency. Inside the IC, two control loops are designed, under synchronized operation frequencies, for a boost regulator and an inverter. The main function of the boost regulator control loop is to supply a steady DC voltage for the inverter. In designing the inverter's control circuit, an adjustable‐frequency adjustable‐voltage soft‐start technique is used to start the lamps. We also use burst mode digital dimming technique to achieve synchronized dimming for the parallel‐connected lamp‐ignition circuits. The feedback voltage from the CCFLs can determine if any lamp is abnormal via a proposed lamp abnormality detection circuit. To deal with the equivalent‐circuit's component parameter differences among various manufacturers' and brands' piezoelectric transformers (PTs), the inverter's operation frequency is designed fine‐tunable in this study. Finally, the proposed design concept was implemented with an actual control IC and a driving circuit for CCFLs. The measured data and waveforms from our test circuitry are presented, which verifies the validity of the miniaturized controller proposed in this study. Copyright © 2008 John Wiley & Sons, Ltd.
Fast computation of the discrete Hartley transform
Authors: Jain Priyanka , Kumar Balbir , Jain S. B.
Published: November 2008

The discrete Hartley transform (DHT) is a real‐valued transform closely related to the discrete Fourier transform (DFT) of a real‐valued spectrum which preserves some useful properties of DFT. In this paper, an algorithm is proposed to realize one‐dimensional DHT with sequence lengthN=2(2 ×m),m⩾2. The proposed algorithm requires fewer multiplications than some of the algorithms in the literature. Copyright © 2008 John Wiley & Sons, Ltd.
Development of multi‐degree‐of‐freedom bilateral forceps robot system using FPGA
Authors: Ishii Ena , Katsura Seiichiro , Nishi Hiroaki , Ohnishi Kouhei
Published: November 2008

Fast growing use of minimally invasive endoscopic surgeries called for development of robots assisting in such procedures. However, existing surgical robots cannot transmit tactile sensation to the operator. To overcome this shortcoming, a bilateral teleoperation method was developed making it possible to accurately convey tactile sensation in single‐degree‐of‐freedom forceps robots. This paper deals with the development of a multi‐degree‐of‐freedom bilateral forceps robot system for surgical procedures which can adapt to actual conditions of the surgery.

Bilateral teleoperation of multi‐degree‐of‐freedom robots requires exchange of environmental information between master and slave devices in common coordinates. In this study we adopted mode coordinates which are better related to the motion of the robot. We also proposed a method to decouple the mechanical interference in mode coordinates. An FPGA‐based controller introduced in this study makes it possible to reduce data processing time and to use hardware‐based real‐time control. As a result, multi‐degree‐of‐freedom force feedback is attained. The experimental results show the viability of the proposed method. © 2008 Wiley Periodicals, Inc. Electron Comm Jpn, 91(6): 23–33, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10118
Determination of cis/trans phase of variations in the MC1R gene with allele‐specific PCR and single base extension
Authors: Mengel‐From Jonas , Børsting Claus , Sanchez Juan J. , Eiberg Hans , Morling Niels
Published: November 2008

The MC1R gene encodes a protein with key regulatory functions in the melanin synthesis. A multiplex PCR and a multiplex single base extension protocol were established for genotyping six exonic MC1R variations highly penetrant for red hair (R), four exonic MC1R variations weakly penetrant for red hair (r), two frameshift variations highly penetrant for red hair (R) and three variations in the promoter region. We genotyped 600 individuals from Denmark using either CE or MALDI‐TOF MS as the detection platform. A total of 62 individuals were genotyped R/R and among the 62 individuals, 57 had red hair and five had blond hair colour. Two different R alleles may be located in cis (RR/−) position or trans (R/R) position, and the phenotype associated with RR/− and R/R may be different. Two allele‐specific PCRs were established with primers targeting the −G445A variation in the MC1R promoter and the allele‐specific PCR products were used in the multiplex single base extension assay. In all 62 individuals, the MC1R variants were situated in trans position. Another 18 individuals with red hair colour were either genotyped R/− or R/r, suggesting that other genes influence hair colour.
Decreasing effective nanofluidic filter size by modulating electrical double layers: Separation enhancement in microfabricated nanofluidic filters
Authors: Bow Hansen , Fu Jianping , Han Jongyoon
Published: November 2008

Conventional methods for separating biomolecules are based on steric interactions between the biomolecules and randomly oriented gel fibers. The recently developed artificial molecular sieves also rely on steric interactions for separation. In this work, we present an experimental investigation of a method that can be used in these sieves to increase separation selectivity and resolution. This method exploits the electrostatic repulsion between the charged molecules and the charged nanofluidic structure. Although this method has been mentioned in the previous work, it has not been examined in detail. We characterize this method by comparing the selectivity with that achieved in devices with different dimensions. The results of this study are relevant to the optimization of chip‐based gel‐free biomolecule separation and analysis.
Multiplex single base extension method for simultaneous genotyping of non‐synonymous SNP in the three human SOD genes
Authors: Iida Reiko , Tsubota Etsuko , Takeshita Haruo , Yasuda Toshihiro
Published: November 2008

The superoxide dismutases (SOD) are a family of enzymes that function as the first line of antioxidant defense against highly reactive superoxide radicals. In SOD genes, a number of SNP have been identified and their associations with various diseases have been reported. In the present study, we applied a multiplex single base extension technique to genotype multiple non‐synonymous SNP in the SOD1, SOD2 and SOD3 genes simultaneously, and examined allele distributions in healthy Caucasian (German), Asian (Japanese) and African (Xhosa) populations. Of the ten SNP investigated, two (SOD2 Ala16Val, SOD3 Ala58Thr) were polymorphic in all three ethnic groups and the genotype distributions showed significant inter‐group differences. On the other hand, a small number of heterozygotes were observed for three SNP (SOD2 Ser10Ile, SOD3 Ala91Thr, SOD3 Arg231Gly) and no heterogeneity was observed for the remaining five (SOD1 Thr40Ile, SOD1 Asn87Ser, SOD2 Arg156Trp, SOD2 Gly76Arg, SOD2 Glu66Val). Analyses of associations between SOD genotypes and levels of plasma SOD activity demonstrated that SOD2 Ala16Val, a dimorphism leading to substitution in the mitochondrial targeting sequence of SOD2, significantly influences plasma SOD2 activity, and that SOD3 Arg231Gly, leading to substitution in the heparin‐binding domain of SOD3, significantly influences plasma total SOD activity.
Quantitative benchmark computations of two‐dimensional bubble dynamics
Authors: Hysing S. , Turek S. , Kuzmin D. , Parolini N. , Burman E. , Ganesan S. , Tobiska L.
Published: November 2008

Benchmark configurations for quantitative validation and comparison of incompressible interfacial flow codes, which model two‐dimensional bubbles rising in liquid columns, are proposed. The benchmark quantities: circularity, center of mass, and mean rise velocity are defined and measured to monitor convergence toward a reference solution. Comprehensive studies are undertaken by three independent research groups, two representing Eulerian level set finite‐element codes and one representing an arbitrary Lagrangian–Eulerian moving grid approach.

The first benchmark test case considers a bubble with small density and viscosity ratios, which undergoes moderate shape deformation. The results from all codes agree very well allowing for target reference values to be established. For the second test case, a bubble with a very low density compared to that of the surrounding fluid, the results for all groups are in good agreement up to the point of break up, after which all three codes predict different bubble shapes. This highlights the need for the research community to invest more effort in obtaining reference solutions to problems involving break up and coalescence.

Other research groups are encouraged to participate in these benchmarks by contacting the authors and submitting their own data. The reference data for the computed benchmark quantities can also be supplied for validation purposes. Copyright © 2008 John Wiley & Sons, Ltd.
Large‐eddy simulation of compressible flows using a spectral multidomain method
Authors: Sengupta K. , Jacobs G. B. , Mashayek F.
Published: November 2008

This paper discusses the development of a high‐order, multidomain‐based large‐eddy simulation (LES) methodology for compressible flows. The LES model equations are approximated on unstructured grids of non‐overlapping hexahedral sub‐domains providing geometric flexibility. In each domain a high‐order Chebyshev polynomial approximation represents the solution ensuring a highly accurate approximation with little numerical dispersion and diffusion. The sub‐grid scale stress in the filtered LES equations is modeled with a dynamic eddy‐viscosity model, while the heat flux is represented with an eddy diffusivity model, employing a turbulent Prandtl number. The model constants are evaluated through a flexible dynamic procedure that uses a high‐order domain level filtering for the discrete test filter. The LES methodology is tested in a decaying isotropic turbulence and a channel flow. The LES method improves the resolution of the turbulence spectrum as compared with a direct numerical simulation (DNS) with the same method at the same grid resolution. The averaged and second‐order statistics for LES computations are in close agreement with published results and resolved DNS. The high‐order LES methodology requires fewer degrees of freedom as compared with lower‐order LES methodologies to accurately resolve the turbulent flows. Copyright © 2008 John Wiley & Sons, Ltd.
Tobler's oyster and the age of the Tabir Formation, Jambi Province, central Sumatra
Authors: Crow M. J. , Van Waveren I. M. , Donovan S. K.
Published: November 2008

For over 85 years, the stratigraphic determination of the Tabir Formation of Sumatra has been confused by a single fossil identification. Professor Fritz Frech recognized a specimen collected at the Batoe Kidjing locality by August Tobler to be an indeterminate, diminutive, ribbed oyster. Subsequently, this formation has been considered Upper Jurassic, perhaps Kimmeridgian, by several authors on the basis of this scant and inconclusive evidence; indeed, at least one author referred this sample to the genus Ostrea. However, these specimens are neither ribbed nor can they be demonstrated to be oysters; rather, this rock fragment contains a number of indeterminate mouldic fragments of fossils, too poorly preserved for confident identification. Modern determinations of the Tabir Formation as of Late Permian age are not contested by the evidence of this specimen. Copyright © 2008 John Wiley & Sons, Ltd.
Cognition following bilateral deep brain stimulation surgery of the subthalamic nucleus for Parkinson's disease
Authors: Halpern Casey H. , Rick Jacqueline H. , Danish Shabbar F. , Grossman Murray , Baltuch Gordon H.
Published: November 2008

Objective

Parkinson's disease (PD) is a neurodegenerative disorder characterized by significant motor dysfunction and various non‐motor disturbances, including cognitive alterations. Deep brain stimulation (DBS) is an increasingly utilized therapeutic option for patients with PD that yields remarkable success in alleviating disabling motor symptoms. DBS has additionally been associated with changes in cognition, yet the evidence is not consistent across studies. The following review sought to provide a clearer understanding of the various cognitive sequelae of bilateral subthalamic nucleus (STN) DBS while taking into account corresponding neuroanatomy and potential confounding variables.

Design

A literature search was performed using the following inclusion criteria: (1) at least five subjects followed for a mean of at least 3 months after surgery; (2) pre‐ and postoperative cognitive data using at least one standardized measure; (3) adequate report of study results using means and standard deviations.

Results

Two recent meta‐analyses found mild post‐operative impairments in verbal learning and executive function in patients who underwent DBS surgery. However, studies have revealed improved working memory and psychomotor speed in the ‘on’ vs ‘off’ stimulation state. A deficit in language may be a consequence of the surgical procedure.

Conclusions

While cognitive decline has been observed in some domains, our review of the data suggests that STN DBS is a worthwhile and safe method to treat PD. Copyright © 2008 John Wiley & Sons, Ltd.
Assessing the relationship between health utilities, quality of life, and health services use in Alzheimer's disease
Authors: Miller Edward Alan , Schneider Lon S. , Rosenheck Robert A.
Published: November 2008

Objectives

To examine the relationship between use of multiple health services and health utilities, quality of life and other factors in Alzheimer's disease (AD).

Design

Data were obtained via caregiver proxy at baseline and 3‐ 6‐ and 9‐months post‐random assignment among 421 community‐dwelling AD patients participating in the CATIE‐AD trial of anti‐psychotic medications. Service use includes both institutional and outpatient services. Correlates include the AD‐Related Quality of Life Scale (ADRQoL), Health Utilities Index (HUI)‐III, Neuropsychiatric Inventory, Mini Mental Status Examination, and AD‐Cooperative Study Activities of Daily Living Scale. Chi squared tests, t‐tests and logistic regression (using general estimating equations) were used to examine the correlates of service use.

Results

Three quarters (74.2%) used at least one service each month. Average monthly utilization rates for specific service types were: 4.5%, inpatient hospital; 5.6%, nursing home; 3.9%, residential care; 44.0%, AD‐related outpatient; 9.4%, mental health outpatient; and 45.5%, medical‐surgical outpatient. The likelihood of using any service was higher among older patients [Odds Ratio (OR) = 1.03] and non‐Hispanic Whites (OR = 1.61). Each 0.10 increment on the Health Utilities Index (HUI)‐III was associated with a 7.0% decrease in the odds of using one or more service (OR = 0.93). The odds of using outpatient and institutional services were 6.0% and 10.0% lower, respectively, for each 0.10 increment on the HUI‐III (OR = 0.94, OR = 0.90). The AD‐Related Quality of Life Scale proved significantly related to outpatient medical‐surgical services only (OR = 1.01).

Conclusion

Findings suggest that the HUI‐III could be combined with other known correlates of service use to inform population planning associated with AD. Copyright © 2008 John Wiley & Sons, Ltd.
Ultrasound bone mass in schizophrenic patients on antipsychotic therapy
Authors: Rey‐Sánchez Purificación , Lavado‐García Jesús M , Canal‐Macías María L , Gómez‐Zubeldia María A , Roncero‐Martín Raúl , Pedrera‐Zamorano Juan D
Published: November 2008

Objective

To determine bone mass using quantitative phalangeal bone ultrasound in institutionalized schizophrenic patients under chronic treatment with antipsychotic drugs.

Methods

A total of 73 patients with schizophrenia (25 women, mean age 59.84 ± 17.01 years; 48 men, mean age 61.89 ± 12.95 years) and 73 healthy subjects (25 women, mean age 60.37 ± 17.16 years; 48 men, mean age 61.24 ± 13.09 years) participated in the study. Bone status was assessed using an ultrasound device that measures the amplitude‐dependent speed of sound (Ad‐SoS) in metres per second. Measurements were made on the phalanges (II–V) of the non‐dominant hand, and the mean value was computed.

Results

The schizophrenic women had higher levels of prolactin (PRL), parathyroid hormone (PTH), alkaline phosphatase (AlPh), and tartrate‐resistant acid phosphatase (TRAP) (all p < 0.0001), and lower 25‐hydroxyvitamin D(25(OH)D3) levels (p < 0.0001) and Ad‐SoS values (p < 0.05) than controls. Ad‐SoS was higher in schizophrenic men (p < 0.05).

Conclusions

Schizophrenic women in treatment with antipsychotic drugs had a loss of phalangeal bone mass that was associated with the levels of vitamin D or PTH, and increased bone turnover. Copyright © 2008 John Wiley & Sons, Ltd.
Caffeine, cognitive failures and health in a non‐working community sample
Authors: Smith Andrew P
Published: November 2008

Rationale

Most studies of the effects of caffeine on performance have been conducted in the laboratory and further information is required on the real‐life effects of caffeine consumption on cognition. In addition, possible effects of caffeine consumption on a range of health outcomes should also be assessed in these studies to enable cost‐benefit analyses to be conducted.

Objectives

Secondary analyses of a large epidemiological database (N = 3223 non‐working participants, 57% female, with a mean age of 49.6 years, range 17–92 years) were conducted to examine associations between caffeine consumption (mean caffeine consumption was 140 mg/day, range 0–1800 mg) and cognitive failures (errors of memory, attention and action) in a non‐working sample. Associations between caffeine consumption and physical and mental health problems were also examined.

Methods

The study involved secondary analyses of a database formed by combining the Bristol Stress and Health at Work and Cardiff Health and Safety at Work studies. Associations between caffeine consumption and frequency of cognitive failures and health outcomes were examined in a sample of non‐workers.

Results

After controlling for possible confounding factors significant associations between caffeine consumption and fewer cognitive failures were observed. Initial analyses suggested that many health variables were associated with regular level of caffeine consumption. However, most of the significant effects of caffeine disappeared when demographic and lifestyle factors were controlled for. Consumption of caffeine was, however, associated with a reduced risk of depression. These effects were also observed in separate analyses examining the source of the caffeine (coffee and tea).

Conclusions

Overall, the results show that caffeine consumption may benefit cognitive functioning in a non‐working population. This confirms earlier findings from working samples. This beneficial effect of caffeine was not associated with negative health consequences. Indeed, consumption of caffeine was found to be associated with a reduced risk of depression. Copyright © 2008 John Wiley & Sons, Ltd.
Vitamin D and sun protection: The impact of mixed public health messages in Australia
Authors: Youl Philippa H. , Janda Monika , Kimlin Michael
Published: November 2008

Exposure of the skin to sunlight can cause skin cancer and is also necessary for cutaneous Vitamin D production. Media reports have highlighted the purported health benefits of Vitamin D. Our aim was to examine attitudes and behaviours related to sun protection and Vitamin D. A cross‐sectional study of 2,001 residents in Queensland, Australia, aged 20–70 years was undertaken. Information collected included the following: skin cancer risk factors; perceptions about levels of sun exposure required to maintain Vitamin D; belief that sun protection increases risk of Vitamin D deficiency; intention, and actual change in sun protection practices for adults and children. Multivariate models examined predictors of attitudinal and behavioural change. One‐third (32%) believed a fair‐skinned adult, and 31% thought a child required at least 30 min/day in summer sun to maintain Vitamin D levels. Reductions in sun protection were reported by 21% of adults and 14% of children. Factors associated with the belief that sun protection may result in not obtaining enough Vitamin D included age of ≥60 years (OR = 1.35, 95% CI 1.09–1.66) and having skin that tanned easily (OR = 1.96, 95% CI 1.38–2.78). Participants from low‐income households, and those who frequently used sun‐protective clothing were more likely to have reduced sun protection practices (OR = 1.33, 95% CI 1.10–1.73 and OR = 1.73, 95% CI 1.36–2.20, respectively). This study provides evidence of reductions in sun protection practices in a population living in a high UV environment. There is an urgent need to refocus messages regarding sun exposure and for continued sun protection practices. © 2008 Wiley‐Liss, Inc.
Assessment of the irrigation performance of transferred schemes in Turkey: a case study analysis
Authors: Cakmak Belgin , Kibaroglu Aysegul , Kendirli Berna , Gokalp Zeki
Published: November 2008

Efforts to increase the amount of irrigation schemes transferred to irrigation associations (IAs) in Turkey have been motivated by the poor performance – in terms of cost recovery, equity, efficiency in operation and maintenance (O&M) and repairs – of many large irrigation schemes by government agencies, namely the State Hydraulic Works (DSI). The objective of this study is to assess the irrigation system performance of transferred irrigation schemes in the DSI Fifth Regional Directorate service area mainly for the year 2003 with benchmarking indicators.

According to the findings of the study, relative water supply was recorded as 1.5–8.4 respectively. The financial performance indicators including cost recovery ratio, maintenance expenditure to revenue ratio, operating cost per unit area, total cost per person employed on water delivery, revenue collection performance and service area per personnel were found to be 1.0–10.6%, 0.7–12.5%, US$6.5–53.3 ha−1, US$636.0–7045.9 per person, 78–95%, 67–13 000 ha per person, respectively. As regards productive performance, output per unit command area, output per unit irrigated area, output per unit irrigation supply and output per unit water consumed were determined as US$325.2–2745.1, US$1028.03–5070.9 ha−1, US$0.2–0.7 m−3 and US$0.2–2.6 m−3 respectively. Water quality classes were found to be C3S1 in all schemes. The results of the case study show that following the transfer of irrigation schemes to the user organizations, significant improvements are recorded in irrigation water fee collection rates and financial cost reduction in the systems operated by the IAs. Mixed results are observed in terms of irrigation ratios. While there are improvements in two irrigation schemes, there are evident increases in the water supply ratio in six other irrigation schemes. Management, operation and maintenance (MOM) costs in general and the maintenance costs per se have increased compared to the collected water fees in the case‐study irrigation schemes. Copyright © 2008 John Wiley & Sons, Ltd.
Prp45 affects Prp22 partition in spliceosomal complexes and splicing efficiency of non‐consensus substrates
Authors: Gahura Ondřej , Abrhámová Kateřina , Skružný Michal , Valentová Anna , Munzarová Vanda , Folk Petr , Půta František
Published: November 2008

Human transcription co‐regulator SNW1/SKIP is implicated in the regulation of both transcription elongation and alternative splicing. Prp45, the SNW/SKIP ortholog in yeast, is assumed to be essential for pre‐mRNA processing. Here, we characterize prp45(1–169), a temperature sensitive allele of PRP45, which at permissive temperature elicits cell division defects and hypersensitivity to microtubule inhibitors. Using a synthetic lethality screen, we found that prp45(1–169) genetically interacts with alleles of NTC members SYF1, CLF1/SYF3, NTC20, and CEF1, and 2nd step splicing factors SLU7, PRP17, PRP18, and PRP22. Cwc2‐associated spliceosomal complexes purified from prp45(1–169) cells showed decreased stoichiometry of Prp22, suggesting its deranged interaction with the spliceosome. In vivo splicing assays in prp45(1–169) cells revealed that branch point mutants accumulated more pre‐mRNA whereas 5′ and 3′ splice site mutants showed elevated levels of lariat‐exon intermediate as compared to wild‐type cells. Splicing of canonical intron was unimpeded. Notably, the expression of Prp45(119–379) in prp45(1–169) cells restored Prp22 partition in the Cwc2‐pulldowns and rescued temperature sensitivity and splicing phenotype of prp45(1–169) strain. Our data suggest that Prp45 contributes, in part through its interaction with the 2nd step‐proofreading helicase Prp22, to splicing efficiency of substrates non‐conforming to the consensus. J. Cell. Biochem. 106: 139–151, 2009. © 2008 Wiley‐Liss, Inc.
Maintaining blood–brain barrier integrity: Pericytes perform better than astrocytes during prolonged oxygen deprivation
Authors: Al Ahmad A. , Gassmann M. , Ogunshola O.O.
Published: November 2008

The blood–brain barrier (BBB), consisting of specialized endothelial cells surrounded by astrocytes and pericytes, plays a crucial role in brain homeostasis. Many cerebrovascular diseases are associated with BBB breakdown and oxygen (O2) deprivation constitutes a critical factor that onsets its disruption. We investigated the impact of astrocytes and pericytes on brain endothelial cell permeability and survival during different degrees of O2 deprivation. Prolonged exposure to 1% O2 caused barrier breakdown and exposure to 0.1% O2 dramatically accelerated disruption and induced cell death, mediated at least in part via caspase‐3 activation. Reoxygenation allowed only cells exposed to 1% O2 to re‐establish barrier function. Notably co‐culture with astrocytes and pericytes substantially enhanced barrier function under normoxic conditions, and produced differential responses during O2 deprivation. At 1% O2 astrocytes partially maintained barrier integrity whereas pericytes accelerated its disruption in the short‐term, having positive effects only after prolonged exposure. Unexpectedly, at 0.1% O2 pericytes were more effective than astrocytes in preserving barrier function although the protection afforded by both cells involved inhibition of caspase‐3 pathways. Furthermore, cell‐specific regulation of auto‐ and paracrine VEGF signaling pathways were also in part responsible for the differential modulation of barrier function. Our data suggests that cellular cross‐talk within the neurovascular unit is crucial for preservation of barrier integrity and that pericytes, not astrocytes, play a significant role during severe and prolonged O2 deprivation. J. Cell. Physiol. 218: 612–622, 2009. © 2008 Wiley‐Liss, Inc.
Many‐lined sun skinks (Mabuya multifasciata) do not compensate for the costs of tail loss by increasing feeding rate or digestive efficiency
Authors: Sun Yan‐Yan , Yang Jing , Ji Xiang
Published: November 2008

We used the many‐lined sun skink (Mabuya multifasciata) as a model system to evaluate the energetic and locomotor costs of tail loss, and to examine whether tailless skinks compensate for the costs of tail loss by increasing feeding rate or digestive efficiency. We successively removed three tail segments from each of the 20 experimental skinks initially having intact tails. Energy content in each removed tail segment was measured, and swimming performance was measured for each experimental skink before and after each tail‐removing treatment. Another independent sample of 19 skinks with intact tails were measured for swimming performance to serve as controls for successive measurements taken for the experimental skinks. Tailless experimental skinks and control skinks were then measured for food intake and digestive efficiency. Tail loss affected swimming speed, but the adverse influence was not significant until more than 55% of the tail (in length) was lost. Our data show that partial tail loss may not severely affect energy stores or locomotor performance in M. multifasciata. However, as tail breaks occurred more frequently in the proximal portion of the tail in skinks collected from the field, we conclude that caudal autotomy occurring in nature often incurs substantial energetic and locomotor costs. As tailless and tailed skinks did not differ in food intake, apparent digestive coefficient and assimilation efficiency, we conclude that tailless individuals do not compensate for the costs of tail loss by increasing feeding rate or digestive efficiency in M. multifasciata. J. Exp. Zool. 311A:125–133, 2009. © 2008 Wiley‐Liss, Inc.
Online H/D exchange liquid chromatography as a support for the mass spectrometric identification of the oxidation products of melatonin
Authors: Collin Fabrice , Bonnefont‐Rousselot Dominique , Yous Saï , Marchetti Catherine , Jore Daniel , Gardès‐Albert Monique
Published: November 2008

The hydrogen–deuterium exchange of protonated melatonin and its in vitro oxidation end‐products have been examined by liquid chromatography coupled with ion‐trap mass spectrometry. Specific H/D scrambling of protons in the C2 and C4 positions of the indole ring during gas‐phase fragmentation process was observed for both melatonin and its oxidation products. Collision‐induced dissociation spectra showed losses of variably deuterated NH3, H2O and CH3CONH2. In addition, a similar H/D scrambling behaviour was observed for the oxidation products, obtained from the opening of the indole ring by oxidative attack. Fragmentation pathways are proposed and H/D scrambling has been employed as a fingerprint, allowing identification of N1‐acetyl‐5‐methoxykynurenin (AMK), N1‐acetyl‐N2‐formyl‐5‐methoxykynurenin (AFMK), dehydro‐AFMK and hydroxymelatonin as the oxidation products of melatonin in vitro. Copyright © 2008 John Wiley & Sons, Ltd.
A novel, simple and sensitive ligand affinity capture method for detecting molecular interactions by MALDI mass spectrometry
Authors: Jørgensen Ann Louise Worsøe , Juul‐Madsen Helle Risdahl , Stagsted Jan
Published: November 2008

A simple and sensitive ligand affinity capture method (LAC) was developed to detect biotinylated biomolecules bound to a biotin–avidin base by matrix‐assisted laser desorption ionization time‐of‐flight mass spectrometry (MALDI ToF MS). Glass slides covered with a metal film for MALDI MS applications were treated with amino‐silane and derivatized with biotin followed by binding of avidin. Washing buffers with high ionic strength increased the specificity of the subsequent binding of biotinylated biomolecules to the avidin layer. A combined thin layer‐dried droplet method using α‐cyano‐4‐hydroxycinnamic acid (CHCA) in acetone or ethyl acetate resulted in the most intense ions of biotinylated polymyxin B, whereas the matrix conditions did not influence the detection of angiotensin II. Addition of biotinylated biomolecules in the low femtomole to low picomole range resulted in sufficient ion intensity for detection by the LAC method. The LAC concept was extended by binding of biotinylated lipopolysaccharide to the biotin–avidin base followed by preferential capture and specific detection of the binding antagonist polymyxin B. Copyright © 2008 John Wiley & Sons, Ltd.
Stability and accuracy analysis of an extension of the FDTD method to incorporate magnetized ferrites
Authors: Grande Ana , Pereda José A. , González Oscar , Vegas Ángel
Published: November 2008

This paper studies the stability and numerical dispersion of an extension of the original finite‐difference time‐domain (FDTD) method to incorporate magnetized ferrites. This extension is based on discretizing the ferrite equations by means of central differences and averages. Both partially magnetized and saturated ferrites are considered. With the aim of studying the numerical features of the resulting FDTD algorithms, we have considered the propagation of plane‐waves along longitudinally magnetized ferrite materials. This is a simple 1D problem that enables the numerical properties of the algorithms to be studied analytically. A von Neumann stability analysis shows that the stability condition of the original FDTD method is preserved and that the algorithms do not exhibit numerical dissipation. The accuracy of the numerical results is not deteriorated with respect to those obtained in the demagnetized case. Copyright © 2008 John Wiley & Sons, Ltd.
Reducing estimation risk in optimal portfolio selection when short sales are allowed
Authors: Alexander Gordon J. , Baptista Alexandre M. , Yan Shu
Published: November 2008

The issue of estimation risk is of particular interest to the decision‐making processes of portfolio managers who use long–short investment strategies. Accordingly, our paper explores the question of whether a VaR constraint reduces estimation risk when short sales are allowed. We find that such a constraint notably decreases errors in estimates of the expected return, standard deviation, and VaR of optimal portfolios. Furthermore, optimal portfolios in the presence of the constraint are substantially closer to the ‘true’ efficient frontier than those in its absence. Finally, we provide VaR bounds and confidence levels for the constraint that lead to the best out‐of‐sample performance. Copyright © 2008 John Wiley & Sons, Ltd.
Allied health care in Parkinson's disease: Referral, consultation, and professional expertise
Authors: Nijkrake Maarten J. , Keus Samyra H.J. , Oostendorp Rob A.B. , Overeem Sebastiaan , Mulleners Wim , Bloem Bastiaan R. , Munneke Marten
Published: November 2008

There is evidence for the efficacy of allied health care in Parkinson's disease (PD). However, barriers exist that hamper implementation of evidence into daily practice. We conducted a survey to investigate: (1) to what extent PD patients currently utilize allied health care for relevant problems in the core areas of allied health care and (2) the level of PD‐specific expertise among allied health professionals. Questionnaires were sent to 260 patients and 297 allied health professionals. Referral rates were 63% for physical therapy, 9% for occupational therapy, and 14% for speech therapy. PD patients with problems that can potentially be alleviated by input from allied health professionals are often not being referred. Furthermore, most patients were treated by allied health professionals who lacked PD‐specific expertise. Current referral to and delivery of allied health care in PD are suboptimal. Evidence‐based guidelines for allied health care in PD and active implementation of these guidelines are needed. © 2008 Movement Disorder Society
Sonographic substantia nigra hypoechogenicity in polyneuropathy and restless legs syndrome
Authors: Godau Jana , Manz Almut , Wevers Anne‐Kathrin , Gaenslen Alexandra , Berg Daniela
Published: November 2008

Substantia nigra (SN) hypoechogenicity assessed by transcranial B‐mode sonography (TCS) is typical for idiopathic restless legs syndrome (RLS). Here, we investigated whether SN hypoechogenicity may differentiate between polyneuropathy (PNP) patients with and without RLS. Seventy‐five patients with PNP, 65 healthy controls, and 75 patients with idiopathic RLS were investigated. A total of 41.2% patients with PNP additionally suffered from RLS. A total of 44.1% patients with PNP, 10.2% of healthy controls, and 91.2% of patients with idiopathic RLS exhibited SN hypoechogenicity. SN echogenicity did not differ significantly between PNP patients with and without RLS. Thus, TCS seems not suitable for the diagnosis of RLS in patients with PNP. © 2008 Movement Disorder Society
Optimal parameters in the HSS‐like methods for saddle‐point problems
Authors: Bai Zhong‐Zhi
Published: November 2008

For the Hermitian and skew‐Hermitian splitting iteration method and its accelerated variant for solving the large sparse saddle‐point problems, we compute their quasi‐optimal iteration parameters and the corresponding quasi‐optimal convergence factors for the more practical but more difficult case that the (1, 1)‐block of the saddle‐point matrix is not algebraically equivalent to the identity matrix. In addition, the algebraic behaviors and the clustering properties of the eigenvalues of the preconditioned matrices with respect to these two iterations are investigated in detail, and the formulas for computing good iteration parameters are given under certain principle for optimizing the distribution of the eigenvalues. Copyright © 2008 John Wiley & Sons, Ltd.
Thermal conductive PS/graphite composites
Authors: Tu Haoming , Ye Lin
Published: November 2008

Polystyrene (PS) was compounded with graphite that possesses high thermal conductivity and layer structures, and the PS/graphite thermal conductive nano‐composites were prepared. Thermal conductivity of PS improved remarkably in the presence of the graphite, and a much higher thermal conductivity of 1.95 W/m K can be achieved for the composite with 34 vol% of colloidal graphite. The Maxwell‐Eucken model and the Agari model were used to evaluate the thermal conductivity of the composites. For the purpose of improving the interfacial compatibility of PS/graphite, realizing the exfoliation and nano‐dispersion of graphite in the PS matrix, three intercalation methods, including rolling intercalation, solvent intercalation, and pan milling intercalation, were applied to prepare the composites, and the morphologies, thermal conductivities, and mechanical properties of the composites were investigated. It should be noted that the one prepared by pan milling intercalation not only had excellent thermal conductivity but also much higher mechanical properties, resulting from a high degree of layer exfoliation of the graphite, the formation of the chain structure agglomerates of the graphite, and the creation of more conductive paths under the strong shear stress of pan milling. Copyright © 2008 John Wiley & Sons, Ltd.
Effects of methyl methacrylate grafting and in situ silica particle formation on the morphology and mechanical properties of natural rubber composite films
Authors: Satraphan P. , Intasiri A. , Tangpasuthadol V. , Kiatkamjornwong S.
Published: November 2008

The effects of methyl methacrylate (MMA) grafting and in situ formation of silica particles on the morphology and mechanical properties of natural rubber latex (NRL) were investigated. MMA grafting on NRL was carried out using cumyl hydroxy peroxide/tetraethylene pentamine (CHPO/TEPA) as a redox initiator couple. The grafting efficiency of the grafted NR was determined by solvent extractions and the grafted NRL was then mixed with tetraethoxysilane (TEOS), a precursor of silica, coated by adherence to a glass surface to form a film and cured at 80°C. The resultant products were characterized by FT‐IR and transmission electron microscopy. The influence of varying the MMA monomer weight ratio on the surface morphology of the composites was investigated by scanning electron and atomic force microscopy. The PMMA (poly MMA) grafted NRL particles were obtained as a core/shell structure from which the NR particles were the core seed and PMMA was a shell layer. The silane was converted into silica particles by a sol–gel process which was induced during film drying at 80°C. The silica particles were fairly evenly distributed in the ungrafted NR matrix but were agglomerated in the grafted NR matrix. The root‐mean‐square roughness increased with an increasing weight ratio of MMA in the rubber. The in situ silica particles in the grafted NR matrix slightly increased both the modulus and the tear strength of the composite film. Copyright © 2008 John Wiley & Sons, Ltd.
Study on Crystal Structure and Thermal Decomposition Mechanism of a Novel Coordination Compound [Zn(DAT)2(H2O)4](PA)2⋅2H2O
Authors: Cui Yan , Zhang Tonglai , Zhang Jianguo , Yang Li , Zhang Jin , Hu Xiaochun
Published: November 2008

A novel coordination compound [Zn(DAT)2(H2O)4](PA)2⋅2H2O has been synthesized using 1,5‐diaminotetrazole (DAT) as ligands. It crystallizes in the monoclinic space group C2/c, with a=1.51973(19) nm, b=0.67904(9) nm, c=3.0712(4) nm, β=90.507(2)°, V=3.1692(7) nm3, Z=4, and μ=0.888 mm−1. With the intermolecular hydrogen bonds, molecules are linked together to form a three‐dimensional net structure. Thermal decomposition mechanism of the title compound was predicted based on DSC, TG‐DTG, and FT‐IR analyses. The kinetic parameters of the first exothermic process of the title compound were studied applying the Kissinger's and Ozawa–Doyle's methods.
Peripheral zone prostate cancers: Location and intraprostatic patterns of spread at histopathology
Authors: Haffner Jérémie , Potiron Eric , Bouyé Sébastien , Puech Philippe , Leroy Xavier , Lemaitre Laurent , Villers Arnauld
Published: November 2008

BACKGROUND

To describe the precise location of peripheral zone (PZ) prostate cancers at various stages of development and to demonstrate their pattern of intraprostatic spread from their site of origin.

METHODS

PZ cancers defined as cancers located in peripheral zone (PZ) including the anterolateral part of PZ, were identified from radical prostatectomy specimens. PZ cancers morphometric histopathological study included largest surface area, volume and spatial distribution.

RESULTS

Out of 188 PZ cancers, 179 were <4 cm3 and 168 <2 cm3. PZ cancers were still confined to their zone of origin for volumes <2 cm3. Between 2 and 4 cm3, some cancers partially spread into the transition zone or anterior fibromuscular stroma. Sixty‐four and 90% of PZ cancers <4 cm3 were located in the lower and posterior half of the gland respectively. Ten percent were located in the anterior horn of PZ. Overall, non‐index (second) cancers were located in the ipsi and contolateral side of the index cancer (largest) in 31% and 69% of cases, respectively. Cancers <2 cm3 were confined to one lobe in 164 of 168 (98%) cases and not confined in 3 out of 11 (27%) cancers 2–4 cm3. On vertical axis, only cancers ≥2 cm3 involved both apex and base.

CONCLUSIONS

PZ cancers contours and locations are predictable and conform to histological zone boundaries if <2 cm3 in volume. Knowledge of PZ cancers origin and pattern of spread in PZ are of importance for imaging diagnosis, guidance for biopsy and focal therapy. Prostate 69:276–282, 2009. © 2008 Wiley‐Liss, Inc.
Isotopologue fractionation during N2O production by fungal denitrification
Authors: Sutka Robin L. , Adams Gerard C. , Ostrom Nathaniel E. , Ostrom Peggy H.
Published: November 2008

Identifying the importance of fungi to nitrous oxide (N2O) production requires a non‐intrusive method for differentiating between fungal and bacterial N2O production such as natural abundance stable isotopes. We compare the isotopologue composition of N2O produced during nitrite reduction by the fungal denitrifiers Fusarium oxysporum and Cylindrocarpon tonkinense with published data for N2O production during bacterial nitrification and denitrification. The fractionation factors for bulk nitrogen isotope values for fungal denitrification were in the range −74.7 to −6.6‰. There was an inverse relationship between the absolute value of the fractionation factors and the reaction rate constant. We interpret this in terms of variation in the relative importance of the rate constants for diffusion and enzymatic reduction in controlling the net isotope effect for N2O production during fungal denitrification. Over the course of nitrite reduction, the δ18O values for N2O remained constant and did not exhibit a relationship with the concentration characteristic of an isotope effect. This probably reflects isotopic exchange with water. Similar to the δ18O data, the site preference (SP; the difference in δ15N between the central and outer N atoms in N2O) was unrelated to concentration during nitrite reduction and, therefore, has the potential to act as a conservative tracer of production from fungal denitrification. The SP values of N2O produced by F. oxysporum and C. tonkinense were 37.1 ± 2.5‰ and 36.9 ± 2.8‰, respectively. These SP values are similar to those obtained in pure culture studies of bacterial nitrification but quite distinct from SP values for bacterial denitrification. The large magnitude of the bulk nitrogen isotope fractionation and the δ18O values associated with fungal denitrification are distinct from bacterial production pathways; thus multiple isotopologue data holds much promise for resolving bacterial and fungal production. Our work further provides insight into the role that fungal and bacterial nitric oxide reductases have in determining site preference during N2O production. Copyright © 2008 John Wiley & Sons, Ltd.