bluuebunny/crossref_metadata_2025 huggingface dataset:
Trends in prevalence and outcomes of pregnancy in women with pre‐existing type I and type II diabetes
Authors: Bell R , Bailey K , Cresswell T , Hawthorne G , Critchley J , Lewis‐Barned N ,   Northern Diabetic Pregnancy Survey Steering Group
Published: February 2008

Objective  To describe recent trends in prevalence, outcomes and indicators of care for women with pre‐existing type I or type II diabetes.

Design  Regional population‐based survey.

Setting  All maternity units in the North of England.

Population  A total of 1258 pregnancies in women with pre‐existing diabetes delivered between 1996 and 2004.

Methods  Data from the Northern Diabetic Pregnancy Survey. Outcome of pregnancy cross‐validated with the Northern Congenital Abnormality Survey and the Northern Perinatal Mortality Survey.

Main outcome measures  Perinatal mortality, congenital anomaly and total adverse perinatal outcome (perinatal mortality and live births with congenital anomaly).

Results  The prevalence of pregestational diabetes increased from 3.1 per 1000 births in 1996–98 to 4.7 per 1000 in 2002–04 (test for linear trend, P < 0.0001), driven mainly by a sharp increase in type II diabetes. Perinatal mortality declined from 48 per 1000 births in 1996–98 to 23 per 1000 in 2002–04 (P = 0.064). There was a significant reduction in total adverse perinatal outcome rate (P = 0.0194) from 142 per 1000 in 1996–98 to 86 per 1000 in 2002–04. There were substantial improvements in indicators of care before and during pregnancy and in glycaemic control throughout pregnancy, but indicators of preconceptual care, such as use of folic acid, remained disappointing.

Conclusion  We observed improvements in pregnancy care and outcomes for women with diabetes in a region with an established audit and feedback cycle. There remains considerable scope for further improvement, particularly in periconceptual glycaemic control. The rising prevalence of type II diabetes presents a challenge to further improvement.
Resonant Frequency Control Method for Total Artificial Heart: In Vitro Study
Authors: Kosaka Ryo , Sankai Yoshiyuki , Yamane Takashi , Tsutsui Tatsuo
Published: February 2008

Abstract:  In order to develop a therapeutic control method for an artificial heart that adapts to physiological behavior for more effective medical care, we applied a resonant frequency control method to a total artificial heart, and evaluated the effectiveness through an in vitro study. The proposed control method utilizes a resonant frequency that can effectively provide blood flow. This resonant frequency was estimated using the systemic circulation model with an online system identification method in real time from two measured physiological data: aortic pressure and blood flow. The effectiveness of the proposed control method was evaluated using a mock‐up circulation loop. As a result, the system gain under the resonant frequency control increased compared to the control using pulsatile frequencies that were different from the resonant frequency, when the physiological condition was changed. Therefore, we confirmed the proposed control method to be an applicable therapeutic control method that could adapt to physiological behavior for more effective medical care.
MORPHOLOGICAL VARIABILITY AND LIFE CYCLE TRAITS OF THE TYPE SPECIES OF THE DIATOM GENUS CHAETOCEROS, C. DICHAETA1
Authors: Assmy Philipp , Hernández‐Becerril David U. , Montresor Marina
Published: February 2008

Chaetoceros dichaeta Ehrenb. is the type species of the genus Chaetoceros and is one of the dominant planktonic diatom species of the Southern Ocean. A number of varieties and forms have been described for C. dichaeta, which prompted us to investigate the morphological variability in clonal cultures to achieve a better circumscription of the morphological features of this species. We studied eight clonal cultures obtained from the type locality by sequencing the D1‐D3 hypervariable domains of the LSU to assess their genetic identity, following cell‐size reduction and sexual reproduction, and examining the morphological features of cells at different stages of the size reduction process using both LM and EM. Observation of sexual reproduction within clonal strains demonstrated that C. dichaeta is homothallic. The size and morphology of the cells vary considerably during size reduction: cell volume is reduced by over an order of magnitude, and the gradual diminution of the apical axis is accompanied by the elongation of the pervalvar axis. All forms and varieties described for C. dichaeta can be ascribed to the species, with the exception of C. dichaeta f. tenuiformis L. Mangin.
PHYLOGEOGRAPHY OF THE GENUS SPONGITES (CORALLINALES, RHODOPHYTA) FROM CHILE1
Authors: Vidal Rodrigo , Meneses Isabel , Smith Macarena
Published: February 2008

Both the records and the descriptions of the crustose species of coralline algae on the southeastern coast of South America are from the early 1900s. Unlike other algae species on the coast of Chile, the biogeography and distribution of crustose corallines have not been studied despite their abundance. Through recent studies, it has been determined that the genus Spongites is the most conspicuous genus along the rocky intertidal of the Chilean coasts. It is also common to the entire coast of the Southern Hemisphere; however, the relationship between species and the possible reasons for their distribution is unknown. We used nuclear and mitochondrial genetic markers and SEM observations of morphological characters to examine Spongites samples from the Southern Hemisphere and to establish the phylogeographic relationships of Chilean Spongites with specimens from other southern coasts. The combination of these analyses revealed the following: (i) a monophyletic clade that represents the Chilean Spongites and (ii) a paraphyletic clade for South African, New Zealand, and Argentine samples. Consequently, we postulate two nonexclusive hypotheses regarding the relationship of Spongites species in the Southern Hemisphere: (i) a complex history of extinction, speciation, and recolonization that might have erased original Gondwanan split patterns, and (ii) an Antarctic Peninsula origin for the Chilean Spongites species.
ASSESSING PHYLOGENETIC AFFINITIES AND SPECIES DELIMITATIONS IN KLEBSORMIDIALES (STREPTOPHYTA): NUCLEAR‐ENCODED rDNA PHYLOGENIES AND ITS SECONDARY STRUCTURE MODELS IN KLEBSORMIDIUM, HORMIDIELLA, AND ENTRANSIA1
Authors: Sluiman Hans J. , Guihal Caroline , Mudimu Opayi
Published: February 2008

Nuclear‐encoded SSU, group I intron, and internal transcribed spacer (ITS) rDNA sequences were obtained for 16 strains of green algae representing species of Klebsormidium, Hormidiella attenuata, and Entransia fimbriata (for taxonomic authorities, see Table S1 in the supplementary material). The SSU phylogeny resolved a well‐supported clade Klebsormidiales in the Streptophyta that comprised authentic Klebsormidium isolates described recently in a monograph by G. M. Lokhorst and various strains from culture collections. The H. attenuata and En. fimbriata pair was the sister group of Klebsormidium. Certain isolates from culture collections previously identified as “Klebsormidium” emerged as Trebouxiophyceae. Strains assigned to Koliella, Gloeotila, and Stichococcus previously allied with Klebsormidium because of shared morphological and ultrastructural characteristics also belonged to Trebouxiophyceae. Group I introns inserted at Escherichia coli position 516 were found in K. nitens and SAG strain 384‐1, and at position 1506 in H. attenuata and En. fimbriata. Introns were not observed in other Klebsormidiales. Unambiguous alignment of ITS regions of Klebsormidiales was only possible after thermodynamic folding had predicted eight conserved helical domains. The ITS phylogeny provided support for five of the morphospecies recognized by Lokhorst (K. flaccidum, K. elegans, K. bilatum, K. crenulatum, K. mucosum), but the sequences of K. dissectum, K. fluitans, and K. nitens formed an unresolved clade. The species with the earliest origin in the Klebsormidium phylogeny was K. flaccidum. The incongruence between Lokhorst’s morphology‐based cladograms and the ITS phylogenies demonstrated the need for a critical reappraisal of the taxonomy and the morphological and molecular species concept in Klebsormidium on the basis of a more extensive taxonomic and geographic sampling strategy.
Radiofrequency Catheter Ablation of Atrial Fibrillation in Athletes Referred for Disabling Symptoms Preventing Usual Training Schedule and Sport Competition
Authors: FURLANELLO FRANCESCO , LUPO PIERPAOLO , PITTALIS MARIO , FORESTI SARA , VITALI‐SERDOZ LAURA , FRANCIA PIETRO , DE AMBROGGI GUIDO , FERRERO PAOLO , NARDI STEFANO , INAMA GIUSEPPE , DE AMBROGGI LUIGI , CAPPATO RICCARDO
Published: February 2008

Introduction: Atrial fibrillation (AF) may occasionally affect athletes by impairing their ability to compete, and leading to noneligibility at prequalification screening. The impact of catheter ablation (CA) in restoring full competitive activity of athletes affected by AF is not known. The aim of our study was to investigate the effectiveness of CA of idiopathic AF in athletes with palpitations impairing physical performance and compromising eligibility for competitive activities.

Methods and Results: Twenty consecutive competitive athletes (all males; 44.4 ± 13.0 years) with disabling palpitations on the basis of idiopathic drug‐refractory AF underwent 46 procedures (2.3 ± 0.4 per patient) according to a prospectively designed multiprocedural CA approach that consolidates pulmonary veins (PV) isolation through subsequent steps. Preablation, effort‐induced AF could be documented in 13 patients (65%) during stress ECG and significantly reduced maximal effort capacity (176 ± 21 W), as compared with patients with no AF during effort (207 ± 43 W, P < 0.05). At the end of CA protocol, which also included ablation of atrial flutter (AFL) in 7 patients, 18 (90.0%) patients were free of AF and two (10.0%) reported short‐lasting (minutes) episodes of palpitations during 36.1 ± 12.7 months follow‐up. Compared with preablation, postablation maximal exercise capacity significantly improved (from 183 ± 32 to 218 ± 20 W, P < 0.02). All baseline quality of life (QoL) parameters pertinent to physical activity significantly improved (P < 0.05) at the end of CA protocol. All athletes obtained reeligibility and could effectively reinitiate sport activity.

Conclusions: AF, alone or in combination with AFL, may significantly impair maximal effort capacity thereby limiting competitive performance. Multiple PV isolation proved very effective in these patients to restore full competitive activity and allow reeligibility.
Acute Pacing‐Induced Dyssynchronous Activation of the Left Ventricle Creates Systolic Dyssynchrony with Preserved Diastolic Synchrony
Authors: FORNWALT BRANDON K. , CUMMINGS ROSE M. , ARITA TAKESHI , DELFINO JANA G. , FYFE DEREK A. , CAMPBELL ROBERT M. , STRIEPER MARGARET J. , OSHINSKI JOHN N. , FRIAS PATRICIO A.
Published: February 2008

Introduction: Patients with heart block have conventionally received a pacemaker that stimulates the right ventricular apex (RVA) to restore heart rate control. While RVA pacing has been shown to create systolic dyssynchrony acutely, dyssynchrony can also occur in diastole. The effects of acute RVA pacing on diastolic synchrony have not been investigated. RVA pacing acutely impairs diastolic function by increasing the time constant of relaxation, decreasing the peak lengthening rate and decreasing peak negative dP/dt. We therefore hypothesized that acute RVA pacing would cause diastolic dyssynchrony in addition to creating systolic dyssynchrony.

Methods and Results: Fourteen patients (13 ± 4 years old) with non‐preexcited supraventricular tachycardia underwent ablation therapy with subsequent testing to confirm elimination of the tachycardia substrate. Normal cardiac structure and function were then documented on two‐dimensional echocardiography and 12‐lead electrocardiography prior to enrollment. Tissue Doppler images were collected during normal sinus rhythm (NSR), right atrial appendage pacing (AAI), and VVI‐RVA pacing during the postablation waiting interval. Systolic and diastolic dyssynchrony were quantified using cross‐correlation analysis of tissue Doppler velocity curves. Systolic dyssynchrony increased 81% during RVA pacing relative to AAI and NSR (P < 0.01). Diastolic synchrony was not affected by the different pacing modes (P = 0.375).

Conclusion: Acute dyssynchronous activation of the LV created by RVA pacing resulted in systolic dyssynchrony with preserved diastolic synchrony in pediatric patients following catheter ablation for treatment of supraventricular tachycardia. Our results suggest that systolic and diastolic dyssynchrony are not tightly coupled and may develop through separate mechanisms.
Thermal Conductivity of Plasma‐Sprayed Aluminum Oxide—Multiwalled Carbon Nanotube Composites
Authors: Bakshi Srinivas R. , Balani Kantesh , Agarwal Arvind
Published: February 2008

Aluminum oxide nanocomposites reinforced with multiwalled carbon nanotubes (MWNT) were prepared by atmospheric plasma spraying of blended and spray‐dried powders. Thermal conductivity was measured using the laser flash technique for temperatures between 25° and 300°C. An aluminum oxide—4 wt% MWNT nanocomposite prepared from the blended powder showed the highest conductivity, followed by aluminum oxide without nanotubes, 8 and 4 wt% MWNT composite prepared from spray‐dried powder in that order. The thermal conductivity values obtained are rationalized taking into account the crystallite size, porosity, MWNT content, microstructure, and the interfaces and metastable γ‐Al2O3 content present in the nanocomposite.
Crystal Structure and Microwave Dielectric Properties of Alkaline‐Earth Hafnates, AHfO3 (A=Ba, Sr, Ca)
Authors: Feteira Antonio , Sinclair Derek C. , Rajab Khalid Z. , Lanagan Michael T.
Published: February 2008

The crystal structure and microwave (MW) dielectric properties of AHfO3 (A=Ba, Sr, and Ca) ceramics prepared by the solid‐state route have been investigated. X‐ray and electron diffraction show BaHfO3 to be an untilted cubic perovskite (a0a0a0, space group

), whereas SrHfO3 and CaHfO3 are both orthorhombically distorted perovskites (a−b+a−, space group Pnma). AHfO3 ceramics with a relative density ∼90% of the theoretical X‐ray density and microstructures consisting of randomly oriented equiaxed grains were prepared by firing at 1750°C for 6 h. Conventional transmission electron microscopy reveals the occurrence of long parallel ferroelastic domains in the subgrain microstructure of CaHfO3 and SrHfO3. At room temperature and MW frequencies, AHfO3 ceramics, where A=Ba, Sr, and Ca, have ɛr∼24.2, Q×fr∼14 250 GHz (at 8.9 GHz) and τf∼+111 ppm/K; ɛr∼23.5, Q×fr∼33 534 GHz (at 9.3 GHz), and τf∼−63 ppm/K; and ɛr∼21.4, Q×fr∼15 950 GHz (at 8.9 GHz), and τf∼−33 ppm/K, respectively. The ion polarizability for Hf4+ in a cubic perovskite environment is calculated to be 3.32 Å3, whereas in a noncubic environment it increases to 4.36–4.47 Å3. Finally, the dielectric properties of AHfO3 (A=Ba, Sr, and Ca) are compared with their titanate and zirconate counterparts.
Pressure Filtration Model of Ceramic Nanoparticles
Authors: Hirata Yoshihiro , Tanaka Yosuke
Published: February 2008

The consolidation behavior of nanometer‐sized particles at 20–800 nm was examined using a pressure filtration apparatus at a constant compressive rate. The relation of applied pressure (ΔPt)–volume of dehydrated filtrate (Vf) was compared with the established filtration theory for the well‐dispersed suspension. The theory was effective in the early stage of the filtration but deviation between the experiment and the theory started when ΔPt exceeded a critical pressure (ΔPtc). It was found that this deviation is associated with the phase transition from a dispersed suspension to a flocculated suspension at ΔPtc. The factors affecting ΔPtc are the ζ potential, concentration, and size of the particles. Based on the colloidal phase transition, a new filtration theory was developed to explain the ΔPt–ht (height of suspension) relation for a flocculated suspension. Good agreement was shown between the developed theory and experimental results.
Solution‐Based Synthesis of Submicrometer ZrB2 and ZrB2–TaB2
Authors: Xie Yanli , Sanders Thomas H. , Speyer Robert F.
Published: February 2008

Zirconium diboride and a zirconium diboride/tantalum diboride mixture were synthesized by solution‐based processing. Zirconium n‐propoxide was refluxed with 2,4‐pentanedione to form zirconium diketonate. This compound hydrolyzed in a controllable fashion to form a zirconia precursor. Boria and carbon precursors were formed via solution additions of phenol–formaldehyde and boric acid, respectively. Tantalum oxide precursors were formed similarly as zirconia precursors, in which tantalum ethoxide was used. Solutions were concentrated, dried, pyrolyzed (800°–1100°C, 2 h, flowing argon), and exposed to carbothermal reduction heat treatments (1150°–1800°C, 2 h, flowing argon). Spherical particles of 200–600 nm for pure ZrB2 and ZrB2–TaB2 mixtures were formed.
High social class and suicide in persons at risk for schizophrenia
Authors: Silverton L. , Mednick S. A. , Holst C. , John R.
Published: February 2008

Objective:  The relationship between suicide and social class has been equivocal. While some authors have reported that higher social class is related to higher rates of suicide, most other studies report that lower social class is associated with higher rates of suicide. Our study attempted to resolve these inconsistencies by using a High Risk for schizophrenia method.

Method:  Children of women with severe schizophrenia were assessed in 1962. In 2005, when subjects were a mean age of 58 years, we identified those who had committed suicide.

Results:  A higher rate of suicide was associated with risk for schizophrenia in the High‐Risk sample. Higher social class origin was associated with suicide in persons at risk for mental illness.

Conclusion:  Higher social class origin was associated with suicide in subjects at genetic risk for schizophrenia (but not those without risk).
Effects of urban land cover on the local species pool in Britain
Authors: Roy D. B. , Hill M. O. , Rothery P.
Published: February 2008

Regression models were used to quantify the relationship between the amount of urban land and composition of local species pools. There was no evidence that urban land cover increases the richness of plant species, based on a survey of 785 2‐km squares of which 157 had > 10% urban land cover. However, the number of alien plants is significantly higher in urban areas. Complete urbanization approximately doubles the proportion of alien species, and the proportion of aliens is twice as high in southern Britain as in the north. The flora of urban tetrads consists of ubiquitous native species and introduced species characteristic of waste ground, but woodland species are poorly represented. At the tetrad scale. enhanced dispersal by man is not the main factor for maintaining the urban flora; availability of urban habitats and high levels of disturbance are more important. The planned housing expansion to greenfield sites in Britain will increase the proportion of alien species, yet the majority of native species should persist in urban areas if existing woodland is preserved.
An Epidemiologic Study of Aboriginal Adolescent Risk in Canada: The Meaning of Suicide
Authors: MacNeil Melanie S.
Published: February 2008

BACKGROUND:  Current rates of Aboriginal youth suicide suggest that an epidemiologic review is needed to understand the impact of culture, community, and environment specific to suicide within this population.

PURPOSE:  This paper aims to (a) examine the literature on the incidence of suicide with special attention to that of adolescents in Aboriginal communities in Canada, (b) review factors hypothesized to place Aboriginals at risk, and (c) explore research directions that would contribute to our understanding of an Aboriginal perspective of suicide.

CONCLUSION:  A clear description of the meaning of adolescent Aboriginal suicide and an understanding of the factors that create risk is needed.
EMPLOYEE SILENCE ON CRITICAL WORK ISSUES: THE CROSS LEVEL EFFECTS OF PROCEDURAL JUSTICE CLIMATE
Authors: TANGIRALA SUBRAHMANIAM , RAMANUJAM RANGARAJ
Published: February 2008

This study examined the cross‐level effects of procedural justice climate on employee silence—that is, the intentional withholding of critical work‐related information by employees from their workgroup members. In a survey‐based study of 606 nurses nested within 30 workgroups, we found that procedural justice climate moderated the effects of individual‐level antecedents of employee silence. Specifically, when procedural justice climate was higher, the effects of antecedents that inhibit employee silence (e.g., workgroup identification, professional commitment) were stronger. Implications for research and practice are discussed.
Template‐directed Assembly of Signaling Proteins: A Novel Drug Screening and Research Tool
Authors: Shrout Anthony L. , Esposito Edward A. , Weis Robert M.
Published: February 2008

A multitude of proteins reside at or near the cell membrane, which provides a unique environment for organizing and promoting assemblies of proteins that are involved in a variety of cellular signaling functions. Many of these proteins and pathways are implicated in disease. For example, strong links have been established between receptor tyrosine kinases and disease, most notably, cancer. However, a significant impediment to researchers remains: membrane‐associated proteins are difficult to reconstitute and study. Template‐directed assembly represents a powerful new technology that enables the assembly of membrane‐associated proteins. We show that template‐directed assembly restores tyrosine kinase activity and regulation, and provides a way for researchers to build multicomponent assemblies. As an example of better enzyme regulation, the Tie2 tyrosine kinase domain exhibits (biologically relevant) autoinhibitory behavior when template assembled. Also, template‐assembled insulin receptor tyrosine kinase domains exhibit significant autophosphorylation (none detected without template‐directed assembly) and an eightfold increase in substrate phosphorylation (compared to best solution conditions). Thus, template‐directed assembly has a demonstrated ability to effectively produce more biologically relevant results using these commercial reagents. Template‐directed assembly promises to be generally applicable to the signaling networks important for human health, because these pathways frequently contain membrane‐associated proteins that require the organizing influence of a membrane surface.
Regulation of pH in human skeletal muscle: adaptations to physical activity
Authors: Juel C.
Published: February 2008

Regulation of pH in skeletal muscle is the sum of mechanisms involved in maintaining intracellular pH within the normal range. Aspects of pH regulation in human skeletal muscle have been studied with various techniques from analysis of membrane proteins, microdialysis, and the nuclear magnetic resonance technique to exercise experiments including blood sampling and muscle biopsies. The present review characterizes the cellular buffering system as well as the most important membrane transport systems involved (Na+/H+ exchange, Na‐bicarbonate co‐transport and lactate/H+ co‐transport) and describes the contribution of each transport system in pH regulation at rest and during muscle activity. It is reported that the mechanisms involved in pH regulation can undergo adaptational changes in association with physical activity and that these changes are of functional importance.
Influence of Autoinducer‐2 (AI‐2) and Beef Sample Extracts on E. coli O157:H7 Survival and Gene Expression of Virulence Genes yadK and hhA
Authors: Soni K.A. , Lu L. , Jesudhasan P.R. , Hume M.E. , Pillai S.D.
Published: February 2008

ABSTRACT:  Bacterial cell‐to‐cell communication is mediated by autoinducer (AI) molecules such as AI‐2 and has been reported to regulate gene expression in Escherichia coli O157:H7. We have previously shown that ground beef contains compounds that can inhibit sensing of AI‐2 like activity. The hypothesis of this study was that AI‐2 activity observed in conditioned medium (CM) will enhance E. coli O157:H7 survival and expression of virulence genes, whereas compounds inhibitory (such as those present in ground beef extracts) to AI‐2 activity will negate these effects. E. coli O157:H7 luxS mutant strain VS 94 (incapable of synthesizing AI‐2) was employed in these studies. The survival of this enteric bacterial pathogen as a function of AI‐2 activity and the presence of AI‐2 inhibitory compounds was studied at 4 °C. The number of survivors in the presence of AI‐2 was significantly higher compared to the absence of AI‐2, and the addition of ground beef extracts to conditioned medium negated the influence of AI‐2 activity. Autoinducer AI‐2 upregulated selected genes virulence genes (yadK, and hha), whereas the ground beef extract reversed the effect of AI‐2 on the expression of the selected genes.
Effects of Pork Meat Cut and Packaging Type on Lipid Oxidation and Oxidative Products during Refrigerated Storage (8 °C)
Authors: Park S.Y. , Kim Y.J. , Lee H.C. , Yoo S.S. , Shim J.H. , Chin K.B.
Published: February 2008

ABSTRACT:  Lipid oxidation and oxidative products as affected by pork meat cut, packaging method, and storage time were evaluated during refrigerated storage. Pork belly had higher pH and thiobarbituric acid reactive substance (TBARS) values than pork loin, and aerobic‐packaged belly had higher TBARS than vacuum‐packaged counterparts. Loin had higher free fatty acid (FFA) values than belly, and increased FFA values were observed with increased storage time. Peroxide values increased up to 7 d and decreased thereafter. Volatile compounds such as alkanes, aldehydes, ketones, and alcohols with high volatility in belly were higher than those in loin. Nonanoic acid, ethyl ester in belly, and hexadecanoic acid in loin might be considered as indices of lipid oxidation. Overall, vacuum packaging was better than aerobic packaging to retard lipid oxidation and production of oxidative products, and loin was more sensitive to lipid oxidation than belly.
Study of the Biosynthesis of 1‐Octen‐3‐ol Using a Crude Homogenate of Agaricus bisporus in a Bioreactor
Authors: Morawicki R.O. , Beelman R.B.
Published: February 2008

ABSTRACT:  1‐Octen‐3‐ol and 10‐oxo‐trans‐8‐decenoic acid are metabolites of the breakdown of linoleic acid (LA) by mushroom enzymes. These compounds can be produced in a bioreactor using a crude mushroom homogenate and the exogenous addition of LA and oxygen. The factors' duration of blending, mushroom–buffer ratio, effect of a surfactant, whole against partially clarified reaction broths, purity of LA, and utilization of stumps instead of whole mushrooms were studied for their effect on reaction yield using a 1‐L bioreactor. The results showed the feasibility of using the more inexpensive 60%‐pure LA instead of the 99%‐pure LA even when a yield loss was involved. Waste stumps could be used instead of whole mushrooms with a yield decline of 26%.
Relationship of body condition score, live weight, stocking rate and grazing system to the mortality of Angora goats from hypothermia and their use in the assessment of welfare risks
Authors: Mcgregor BA , Butler KL
Published: February 2008

Body condition scoring is widely used for sheep and cattle but the practice is included in only one Code of Practice for the welfare of goats in Australia. There is no published scientific evidence to support or defend its use in the assessment of welfare risks to farmed goats.

Procedure   The significance of stocking rate, grazing system, body condition score (CS) and live weight were investigated in explaining the risk of mortality of individual and flocks of grazing Angora goats from hypothermia following a severe weather event in April. This event occurred 5 weeks after shearing the goats. Angora goats and Saxon Merino sheep were grazed alone, or mixed together in equal numbers at each of three stocking rates.

Results   There was no mortality amongst Angora goats provided they grazed at the lowest stocking rate even when their CS was ≤ 2.0. Mortality in flocks of Angora goats was most related to the CS reached during the preceding 2 months. For flocks of Angora goats there was no mortality at CS ≥ 2.5 and mortality increased sharply at mean CS < 2.0. For individual Angora goats, mortality increased as CS declined and stocking rate and grazing combinations were additive in effect on mortality. Grazing with sheep increased mortality of Angora goats at higher stocking rates. The individual goat mortality rate was not dependent on individual plot effects suggesting that these results are applicable widely. Live weight loss was not related to mortality rates of goats once CS had been accounted for.

Conclusion   It was concluded that CS and stocking rate were highly significant determinants of welfare risk in Angora goats.
Relative importance of risk factors for spruce beetle outbreaks
Authors: Reynolds K.M. , Holsten E.H.
Published: February 2008

Nine factors were initially suggested by spruce beetle (Dendroctonusrufipennis (Kby.)) experts in Alaska as potentially important in determining the risk of a spruce beetle outbreak in stands. Factors suggested were stand hazard, size and trend of spruce beetle population in neighboring stands, degree–days in the past June, total rainfall in the past summer, and availability of four types of breeding material. Risk factors were organized into a hierarchical model of spruce beetle risk, and the relative importance of factors for determining risk was analyzed in three stages with the analytic hierarchy process. This process derives subjective estimates of factor importance values through a process of pair-wise comparisons. Analysis in stage 1 involved independent responses of two experts from Alaska. In stage 2, three experts from Alaska provided responses as a group. In stage 3, five experts, representing Alaska, British Columbia, and the Rocky Mountain region, provided responses as a group. In the final stage of analysis, stand hazard and windthrown trees were identified as the two most important factors determining risk of a spruce beetle outbreak. Hazard and windthrow were considered about equally important and together accounted for almost two-thirds of the total allocation of importance values among risk factors. The analytic hierarchy process is an effective method for eliciting expert knowledge and can be a useful tool for development of expert systems in natural resource management, where even expert knowledge is often incomplete.
Development of Tonic Firing Behavior in Rat Soleus Muscle
Authors: Eken Torsten , Elder Geoffrey C. B. , Lømo Terje
Published: February 2008

Tonic firing behavior in soleus muscle of unrestrained rats aged 7 to ≥100 days was studied by chronic single-motor-unit and gross-electromyographic (EMG) recordings. Median motor-unit firing frequency at 10 days was 19–26 Hz and did not change appreciably after this time, whereas interval-to-interval firing variability was reduced with age. Two units with median frequencies 40 and 59 Hz were encountered in one 7-day-old rat. Integrated rectified gross EMG developed from being phasic only to predominantly tonic during the second and third postnatal week. From the end of the third week, rather short tonic periods with irregular amplitude were replaced by longer lasting constant-amplitude periods. Quantitatively, median duration of gross-EMG activity episodes more than doubled, while 90th-percentile values for episode duration increased 19-fold, from 7.4 s at 7 days to 140 s in adults. The main part of this increase took place after 22 days. Previous work in adult rats has indicated that descending monoaminergic innervation is essential for maintained tonic motoneuron activity, which probably is caused by depolarizing plateau potentials. Such innervation of the lumbar spinal cord matures gradually to an adult pattern and density ∼3–4 wk after birth. The present results, describing a concurrent considerable development of tonic firing behavior, support and extend these findings.
Cellular and Molecular Events Underlying the Dysregulated Response of the Aged Brain to Stroke: A Mini-Review
Authors: Petcu Eugen Bogdan , Sfredel Veronica , Platt Dieter , Herndon James G. , Kessler Christof , Popa-Wagner Aurel
Published: February 2008

Background: Age-related brain injuries, including stroke, are a major cause of physical and mental disabilities. Objective: Therefore, studying the basic mechanism underlying functional recovery after brain stroke in aged subjects is of considerable clinical interest. Methods: This review summarizes the effects of age on recovery after stroke in an animal model, with emphasis on the underlying cellular mechanisms. Results: Data from our laboratory and elsewhere indicate that, behaviorally, aged rats were more severely impaired by stroke than young rats, and they also showed diminished functional recovery. Infarct volume did not differ significantly between young and aged animals, but critical differences were apparent in the cytological response to stroke, most notably an age-related acceleration in the development of the glial scar. Early infarct in older rats is associated with premature accumulation of BrdU-positive microglia and astrocytes, persistence of activated oligodendrocytes, a high incidence of neuronal degeneration and accelerated apoptosis. In aged rats, neuroepithelial-positive cells were rapidly incorporated into the glial scar, but these neuroepithelial-like cells did not make a significant contribution to neurogenesis in the infarcted cortex in young or aged animals. The response of plasticity-associated proteins like MAP1B, was delayed in aged rats. Tissue recovery was further delayed by an age-related increase in the amount of the neurotoxic C-terminal fragment of the β-amyloid precursor protein (A-β) at 2 weeks poststroke. Conclusion: The available evidence indicates that the aged brain has the capability to mount a cytoproliferative response to injury, but the timing of the cellular and genetic response to cerebral insult is dysregulated in aged animals, thereby further compromising functional recovery. Elucidating the molecular basis for this phenomenon in the aging brain could yield novel approaches to neurorestoration in the elderly.
A Canonical Neural Circuit for Cortical Nonlinear Operations
Authors: Kouh Minjoon , Poggio Tomaso
Published: February 2008

A few distinct cortical operations have been postulated over the past few years, suggested by experimental data on nonlinear neural response across different areas in the cortex. Among these, the energy model proposes the summation of quadrature pairs following a squaring nonlinearity in order to explain phase invariance of complex V1 cells. The divisive normalization model assumes a gain-controlling, divisive inhibition to explain sigmoid-like response profiles within a pool of neurons. A gaussian-like operation hypothesizes a bell-shaped response tuned to a specific, optimal pattern of activation of the presynaptic inputs. A max-like operation assumes the selection and transmission of the most active response among a set of neural inputs. We propose that these distinct neural operations can be computed by the same canonical circuitry, involving divisive normalization and polynomial nonlinearities, for different parameter values within the circuit. Hence, this canonical circuit may provide a unifying framework for several circuit models, such as the divisive normalization and the energy models. As a case in point, we consider a feedforward hierarchical model of the ventral pathway of the primate visual cortex, which is built on a combination of the gaussian-like and max-like operations. We show that when the two operations are approximated by the circuit proposed here, the model is capable of generating selective and invariant neural responses and performing object recognition, in good agreement with neurophysiological data.
Spectral Algorithms for Supervised Learning
Authors: Gerfo L. Lo , Rosasco L. , Odone F. , Vito E. De , Verri A.
Published: February 2008

We discuss how a large class of regularization methods, collectively known as spectral regularization and originally designed for solving ill-posed inverse problems, gives rise to regularized learning algorithms. All of these algorithms are consistent kernel methods that can be easily implemented. The intuition behind their derivation is that the same principle allowing for the numerical stabilization of a matrix inversion problem is crucial to avoid overfitting. The various methods have a common derivation but different computational and theoretical properties. We describe examples of such algorithms, analyze their classification performance on several data sets and discuss their applicability to real-world problems.
Phototoxicity of Zinc Oxide Nanoparticle Conjugatesin Human Ovarian Cancer NIH: OVCAR-3 Cells
Authors: Zhang Yongbin , Chen Wei , Wang Shaopeng , Liu Yuanfang , Pope Carey
Published: February 2008

Zinc oxide (ZnO) nanoparticles conjugated to porphyrin (ZnO-MTAP) have been designed, synthesized and evaluated for photodynamic therapy (PDT) against ovarian cancer. Based on the self-lighting photodynamic therapy (SLPDT) concept, photoactivation of ZnO-MTAP conjugates will lead to
release of reactive oxygen species which, if effectively targeted to tumor cells, can elicit selective cytotoxicity. Following synthesis, conjugated nanoparticles were purified using gel exclusion chromatography and tumoricidal activity was evaluated using the human ovarian cancer cell line,
NIH: OVCAR-3. Conjugates generated reactive oxygen species (ROS) in a concentration- and illumination-dependent manner following exposure to ultraviolet A light (365 nm). Cellular uptake of nanoparticle conjugates was detected using laser scanning confocal microscopy. Under dark conditions,
ZnO-MTAP conjugates (1–10 μM, 24 hr) exhibited little cytotoxic potential. Ultraviolet radiation alone (UVA, 9 kJ/m2) also had little effect on cell viability. Co-exposure to both UVA radiation (9 kJ/m2) and ZnO nanoparticle conjugates however, elicited
concentration-dependent cytotoxicity (40% and 92%, respectively). Furthermore, caspase 3/7 activity was markedly elevated 3–6 hours after irradiation, suggesting apoptosis was induced by the phototherapy. These findings provide proof-of-concept that photoactivation of ZnO-MTAP conjugates
can be useful for targeted destruction of tumor cells.
Modulation of Ligand Binding Affinity of Tumorigenic Carbonic Anhydrase XII Upon Interaction with Cationic CdTe Quantum Dots
Authors: Manokaran Sumathra , Berg Alexander , Zhang Xing , Chen Wei , Srivastava D. K.
Published: February 2008

The structural data of tumorigenic carbonic anhydrase (CA) XII revealed that the enzyme surface opposite to the active site pocket was negatively charged, and thus it had potential to interact with the positively charged surfaces. We investigated the influence of cationic CdTe quantum dots on the catalytic and ligand binding properties of the enzyme. Although cationic quantum dots interacted with CAXII (with aKdvalue of 2.1μM), they did not impair the enzyme's catalytic activity, suggesting that the accessibility of the enzyme's active site remained unaffected by the above interaction. When CAXII bound dansylamide (serving as a fluorescence probe as well as a potent inhibitor of the enzyme) was titrated with cationic quantum dots, the fluorescence spectral profiles revealed a marked transfer of the excited state energy between the above species. However, the binding of quantum dots to CAXII weakened the affinity of dansylamide for the enzyme, and thus obviated the inhibitory feature of the ligand. Since the quantum dots and dansylamide are bound at the opposite sides of CAXII, their influence must be mediated via changes in the protein conformation at a distal region as observed with allosteric enzymes. The mechanistic insights gained from these studies may lead toward developing diagnostic protocols for tumorigenic CAXII.
poly(I:C) and LPS induce distinct IRF3 and NF-κB signaling during type-I IFN and TNF responses in human macrophages
Authors: Reimer Thornik , Brcic Marija , Schweizer Matthias , Jungi Thomas W
Published: February 2008

Macrophages play major roles in the onset of immune responses and inflammation by inducing a variety of cytokines such as TNF and IFN-β. The pathogen-associated molecular pattern, polyinosinic-polycytidylic acid [poly(I:C)], and LPS were used to study type-I IFN and TNF responses in human macrophages. Additionally, activation of the key signaling pathways, IFN-regulatory factor 3 (IRF3) and NF-κB, were studied. We found that TNF production occurred rapidly after LPS stimulation. LPS induced a strong IFN-β mRNA response within a short time-frame, which subsided at 8 h. The IFN-stimulated genes (ISGs), ISG56 and IFN-inducible protein 10, were strongly induced by LPS. These responses were associated with NF-κB and IRF3 activation, as shown by IRF3 dimerization and by nuclear translocation assays. poly(I:C), on the other hand, induced a strong and long-lasting (>12 h) IFN-β mRNA and protein response, particularly when transfected, whereas only a protracted TNF response was observed when poly(I:C) was transfected. However, these responses were induced in the absence of detectable IRF3 and NF-κB signaling. Thus, in human macrophages, poly(I:C) treatment induces a distinct cytokine response when compared with murine macrophages. Additionally, a robust IFN-β response can be induced in the absence of detectable IRF3 activation.
DAMGO-induced expression of chemokines and chemokine receptors: the role of TGF-β1
Authors: Happel Christine , Steele Amber D , Finley Matthew J , Kutzler Michele A , Rogers Thomas J
Published: February 2008

Studies from a number of laboratories suggest that modulation of cytokine expression plays an integral role in the immunomodulatory activity of opioids. Previously, our laboratory reported that activation of the μ-opioid receptor induced the expression of CCL2, CCL5, and CXCL10, as well as CCR5 and CXCR4. Previous work has also suggested the possibility that TGF-β may participate in the opioid-induced regulation of immune competence, and in the present study, we set out to determine the role of this cytokine in the control of chemokine and chemokine receptor expression. We found that D-ala2,N-Me-Phe4-Gly-ol5enkephalin (DAMGO), a highly selective μ-opioid agonist, induced the expression of TGF-β1 expression at the protein and mRNA levels. In turn, the addition of TGF-β1 was found to induce CCL5 and CXCR4 expression but not CCL2, CXCL10, or CCR5. Further analysis showed that pretreatment with neutralizing anti-TGF-β1 blocked the ability of DAMGO to induce CCL5 or CXCR4. Similarly, pretreatment with cycloheximide prevented CCL5 or CXCR4 mRNA expression, consistent with the observation that DAMGO induction of chemokine and chemokine receptor expression requires newly synthesized TGF-β1 protein. These results describe a common molecular basis for the activation of chemokine and chemokine receptor expression and may permit the development of strategies to inhibit certain undesirable immunological properties of μ-opioid agonists such as morphine and heroin.
A role for membrane-bound CD147 in NOD2-mediated recognition of bacterial cytoinvasion
Authors: Till Andreas , Rosenstiel Philip , Bräutigam Karen , Sina Christian , Jacobs Gunnar , Oberg Hans-Heinrich , Seegert Dirk , Chakraborty Trinad , Schreiber Stefan
Published: February 2008

NOD2 is an intracellular receptor for the bacterial cell wall component muramyl dipeptide. Mutations in the leucine-rich repeat region of NOD2, which lead to an impaired recognition of muramyl dipeptide, have been associated with chronic inflammatory diseases of barrier organs such as Crohn disease, asthma and atopic eczema. In this study we identify CD147 (also known as BSG and EMMPRIN), a membrane-bound regulator of cellular migration, differentiation and inflammatory processes, as a protein interaction partner of NOD2. We demonstrate a complex influence of the CD147-NOD2 interaction on NOD2-dependent signaling responses. We show that CD147 itself acts as an enhancer of the invasion of Listeria monocytogenes, an intracellular bacterial pathogen. We propose that the CD147-NOD2 interaction serves as a molecular guide to regulate NOD2 function at sites of pathogen invasion.
Evaluating cytochrome c diffusion in the intermembrane spaces of mitochondria during cytochrome c release
Authors: Gillick Kieran , Crompton Martin
Published: February 2008

Truncated Bid (tBid) releases cytochrome c from mitochondria by inducing Bak (and Bax) pore formation in the outer membrane. An important issue is whether a second tBid action, independent of Bak and Bax, is also required to enhance cytochrome c mobility in the intermembrane spaces. To investigate this, we developed a kinetic analysis enabling changes in the diffusibility of cytochrome c in the intermembrane spaces of isolated mitochondria to be differentiated from changes resulting from Bak activation. Cytochrome c diffusibility in the intermembrane spaces was unaffected by changes in [tBid] over the range 0.5-19.0 pmol per mg of mitochondrial protein, when tBid-dependent Bak activation was increased several-thousand fold. However, high [tBid] (100 pmol mg–1) did increase diffusibility by approximately twofold. This was attributable to the permeability transition. Basal cytochrome c diffusibility in the intermembrane spaces in the absence of tBid was determined to be approximately 0.2 minute–1, which is sufficient to support cytochrome c release with a half-time of 3.4 minutes. It is concluded that tBid has a monofunctional action at low concentrations and, more generally, that the basal cytochrome c diffusibility in the intermembrane spaces is adequate for rapid and complete cytochrome c release irrespective of the mode of outer membrane permeabilisation.
Stabilisation of the distal radioulnar joint with a double-breasted slip of the extensor retinaculum
Authors: Gupta R. K. , Singh H. , Sandhu V. P. S.
Published: February 2008

We describe a method for stabilising the distal radioulnar joint using a double breasted slip of extensor retinaculum.

This is a retrospective series of 30 patients with a painful wrist secondary to instability of the distal radioulnar joint. The results were assessed by a modified Mayo Score. The mean follow-up was for 38.1 months (13 months to 8 years).

Twelve patients had excellent, 16 good and 2 fair outcomes. One patient had experienced temporary numbness in the distribution of the dorsal branch of the ulnar nerve. The modified Mayo wrist score increased from a pre-operative mean of 23.89 (10 to 50) to a final mean of 94.4 (85 to 100).

Stabilisation of the distal radioulnar joint by the method of using a double breasted slip of the extensor retinaculum gives satisfactory results. The procedure is simple and reproducible.