bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessing the New Literacies of Online Reading Comprehension: An Informative Interview With W. Ian O'Byrne, Lisa Zawilinski, J. Greg McVerry, and Donald J. Leu at the University of Connecticut
Authors: Mokhtari Kouider , Kymes Angel , Edwards Patricia
Published: November 2008

The constantly changing nature of literacy, brought about by the Internet and other forms of information and communication technologies (ICTs), has pressed researchers and practitioners to seek new ways of addressing the complexities of reading comprehension and writing on and with the Internet. In this brief interview, members of the New Literacies Research Lab share valuable insights on the assessment of the new literacies of online reading comprehension.

قد ضغطت طبيعة معرفة القراءة والكتابة الدائمة التغير الناتجة عن الشبكة العالمية وأنواع أخرى من تقنيات المعلومات والمواصلات على الباحثين والممارسين للبحث عن طرق جديدة لتتناول تعقيدات استيعاب القراءة والكتابة على الشبكة العالمية. وفي هذه المقابلة الموجزة يشارك أعضاء مختبر أبحاث معارف القراءة والكتابة الجديدة نفاذ بصيرتهم القيم بصدد تقييم المعارف الجديدة في استيعاب القراءة على الشبكة العالمية.

由于互联网及其他资讯通讯科技的不同读写形式对读写能力的本质所带来的不断变化，教育研究员和教育从业员不得不寻找新的方法，以应付在互联网上的写作和用互联网写作的复杂性，及阅读理解这些写作的复杂性。在这个简短的访谈中，「新读写能力研究实验室」的几位成员分享他们对线上阅读理解的新读写能力评估的一些宝贵见解。

La nature en changement constant de la littératie, portée par Internet et d'autres formes des technologies de l'information et de la communication (ICTs), a poussé les chercheurs et les praticiens à chercher de nouveaux moyens pour affronter les complexités de la compréhension de la lecture et de l'écriture sur et avec Internet. Dans ce bref entretien, des membres du Laboratoire de recherche sur les nouvelles littératies mettent en commun des idées intéressantes concernant l'évaluation des nouvelles littératies de la compréhension en ligne de la lecture.

Благодаря Интернету и другим информационным и коммуникационным технологиям смысл, который мы вкладываем в понятие грамотность, постоянно меняется. Это вынуждает исследователей и практиков искать новые пути для преодоления сложностей при восприятии прочитанного и при письме – теперь уже для пользователей Интернета. В этом кратком интервью сотрудники Лаборатории исследования новых видов грамотности делятся с читателями важными соображениями, связанными с оцениванием навыков, необходимых для понимания прочитанного в сети.

La naturaleza constantemente cambiante de las competencias, producida por el Internet y otras tecnologías de información y comunicación (ICTs por sus siglas en inglés), ha obligado a investigadores y practicantes a buscar nuevas maneras de enfrentar las complejidades de la comprensión de lectura y la escritura en y con el Internet. En esta entrevista breve, miembros del Laboratorio de Investigación de Nuevas Competencias comparten sus ideas sobre el evaluación de estas nuevas competencias de la comprensión de lectura en la red.
Wastewater reuse: how integrated and sustainable is the strategy?
Authors: Neubert Susanne
Published: November 2008

The aim of this paper is to show that the three dimensions, irrigation, fertilization and disposal must be integrated if the reuse of treated wastewater (RTW) in agriculture is to become an ecologically sustainable and hygienically safe approach. Integration is a real option in both newly industrializing countries and poor developing countries. The option can be realized by adapting wastewater treatment to the needs of wastewater users as well as to the conditions of recipient soils that serve as a reservoir. This calls for treatment concepts that entail different goals which can be realized with the aid of both near-natural, low-cost methods and technically more demanding and cost-intensive approaches. The problems involved in implementation have less to do with funding needs than with the need for targeted management, a suitable legal framework, and institutions that are able to consistently handle both needs.
Getting over yuck: moving from psychological to cultural and sociotechnical analyses of responses to water recycling
Authors: Russell Stewart , Lux Colleen
Published: November 2008

Discussion of public reactions to water recycling is now framed around the idea of a ‘yuck factor’: advocates tend to assume an emotional response is the primary determinant of people's attitudes to reuse and they despair of people accepting rational arguments on its merits. Academic and consultancy work in the area has been dominated by particular work from social psychology: theories of disgust, models of attitude causation, and psychometric methods for measuring attitudes and determining the influences on them. This paper questions the models, their assumptions, the methods used to apply and validate them, their implications for change, and the practical consequences of framing the problem this way. It suggests that more fruitful explanations and more effective public engagement both require a shift to a more sociological and cultural explanation, one that examines users’ practices around the sociotechnical systems of providing water and handling waste. The paper concludes there are no compelling arguments or evidence that negative reactions to recycled water cannot change with opportunities to learn about the issues; indeed deliberative consultation mechanisms are essential if people are to reach an informed, reasoned and robust evaluation of the option. The ‘yuck’ discourse is of limited value in explaining public responses and counterproductive in formulating strategies for increasing public support.
Typical urban water supply provision in developing countries: a case study of Semarang City, Indonesia
Authors: Hadipuro W. , Indriyanti N.Y.
Published: November 2008

Low service coverage of public water supply companies and high dependency on groundwater are typical characteristics of urban water supply provision in developing countries. A case study of Semarang, Indonesia, shows that such phenomena have a detrimental effect on the environment. Land subsidence, seawater intrusion and sea flooding are, to some extent, the results of the failure of the public water supply company to service all Semarang City inhabitants. The study of the Semarang coastal area shows that the lack of access, especially to the poor, is a business opportunity for small-scale water supply providers. The problem with these providers is that all of them use groundwater as sources. The worse the service of the public water supply company the more necessary it is to regulate groundwater extraction. The poor will become very dependent on groundwater while also becoming victims of environmental degradation due to excessive groundwater extraction. The study shows that all inhabitants, poor and rich alike, are waiting to be supplied by the public water supply company. They will change to the public water supply whenever the service is available.
Energy balance and cost-benefit analysis of biogas production from perennial energy crops pretreated by wet oxidation
Authors: Uellendahl H. , Wang G. , Møller H. B. , Jørgensen U. , Skiadas I. V. , Gavala H. N. , Ahring B. K.
Published: November 2008

Perennial crops need far less energy to plant, require less fertilizer and pesticides, and show a lower negative environmental impact compared with annual crops like for example corn. This makes the cultivation of perennial crops as energy crops more sustainable than the use of annual crops. The conversion into biogas in anaerobic digestion plants shows however much lower specific methane yields for the raw perennial crops like miscanthus and willow due to their lignocellulosic structure. Without pretreatment the net energy gain is therefore lower for the perennials than for corn. When applying wet oxidation to the perennial crops, however, the specific methane yield increases significantly and the ratio of energy output to input and of costs to benefit for the whole chain of biomass supply and conversion into biogas becomes higher than for corn. This will make the use of perennial crops as energy crops competitive to the use of corn and this combination will make the production of biogas from energy crops more sustainable.
Heterotrophic denitrification on granular anammox SBR treating urban landfill leachate
Authors: Ruscalleda M. , López H. , Ganigué R. , Puig S. , Balaguer M. D. , Colprim J.
Published: November 2008

The anammox process was applied to treat urban landfill leachate coming from a previous partial nitritation process. In presence of organic matter, the anammox process could coexist with heterotrophic denitrification. The goal of this study was to asses the stability of the anammox process with simultaneous heterotrophic denitrification treating urban landfill leachate. The results achieved demonstrated that the anammox process was not inactivated by heterotrophic denitrification. Moreover, part of the nitrate produced by anammox bacteria and part of the influent nitrite were removed by heterotrophic denitrifiers with associated biodegradable organic matter consumption. In this sense, the contribution on nitrogen removal of each process was calculated using a nitrogen mass balance methodology. An 85.1±5.6% of the nitrogen consumption was achieved via anammox process while the average heterotrophic denitrifiers contribution was 14.9±5.6%. Heterotrophic denitrification was limited by the available easily biodegradable organic matter.
Climate change impact on water balance of Lake Balaton
Authors: Nováky Béla
Published: November 2008

Impact of climate change on average annual water balance of Lake Balaton was examined under different climate scenarios. Increase in annual temperature by 1.5°C and decrease in annual precipitation by 5% are likely to lead to considerable decrease in water recharge of lake. If an increase in annual temperature by 2.8°C is coupled with a decrease in precipitation by 10%, Lake Balaton could turn into a closed lake without outflow.
Peripheral Sensory Neuropathy Associates With Micro- or Macroangiopathy
Authors: Kärvestedt Lars , Mårtensson Eva , Grill Valdemar , Elofsson Stig , von Wendt Gunvor , Hamsten Anders , Brismar Kerstin
Published: November 2008

OBJECTIVE—To assess associations between peripheral sensory neuropathy (PSN) and other diabetes-related complications.

RESEARCH DESIGN AND METHOD—In an area-based cohort of type 2 diabetic subjects, we investigated 156 subjects (age 61.7 ± 7.2 years and diabetes duration 7.0 ± 5.7 years) by questionnaires, clinical examinations, blood and urine sampling, and review of medical records.

RESULTS—Prevalence of PSN, assessed by monofilament and neurothesiometer testing, increased with severity of retinopathy (50% frequency in moderate and 100% in severe or proliferative retinopathy; P = 0.02). Vibration perception threshold was higher in subjects with retinopathy (25.6 ± 8.9 vs. 20.5 ± 8.9 V; P = 0.007). PSN was more common in subjects with overt nephropathy, with higher vibration perception thresholds, than in subjects without overt nephropathy. Subjects with PSN but no retinopathy had twice the prevalence of peripheral vascular disease (PVD) (52%) as subjects with both PSN and retinopathy (19%; P = 0.05). In subjects with PSN alone, PVD was three times more likely (52%) than in subjects without PSN (16%; P = 0.001). In multivariate analysis, PSN was independently associated with PVD (odds ratio 2.31; P = 0.007), age (1.12; P = 0.008), male sex (2.01; P = 0.02), and HDL cholesterol (0.21; P < 0.05) and tended to be independently associated with IGF-1 binding protein (1.03; P = 0.05) but not with diabetes duration or A1C.

CONCLUSIONS—In a representative population of type 2 diabetes, PSN is related to microvascular and macrovascular pathology. PSN is possibly affected by the IGF axis.
Acute cerebral ischemia following intraventricular hemorrhage in moyamoya disease: early perfusion computed tomography findings
Authors: Su I-Chang , Yang Chi-Cheng , Wang Wei-Han , Lee Jing-Er , Tu Yong-Kwang , Wang Kuo-Chuan
Published: November 2008

The authors present a rare case of an infarction complication 15 days following acute intraventricular bleeding due to moyamoya disease. Before the infarction occurred, perfusion CT imaging disclosed early but reversible ischemic injury on the day of hemorrhage. Dehydration and hypotension are both possibly contributing factors of progressive injury from reversible ischemia due to infarction. Although the patient underwent successful bypass surgery, 1 month after the ictus the neurobehavior evaluation still showed marked executive dysfunction. The authors address that, in hemorrhagic-type moyamoya disease, early perfusion CT scanning is not only a powerful tool to identify the high-risk group of patients who could experience subacute infarction, but also alarms neurosurgeons to eliminate any predisposing factors when it shows reversible ischemic injuries.
Management of hypertensive emergencies in acute brain disease: evaluation of the treatment effects of intravenous nicardipine on cerebral oxygenation
Authors: Narotam Pradeep K. , Puri Varun , Roberts John M. , Taylon Charles , Vora Yashail , Nathoo Narendra
Published: November 2008

Object

Inappropriate sudden blood pressure (BP) reductions may adversely affect cerebral perfusion. This study explores the effect of nicardipine on regional brain tissue O2 (PbtO2) during treatment of acute hypertensive emergencies.

Methods

A prospective case–control study was performed in 30 patients with neurological conditions and clinically elevated BP. All patients had a parenchymal PbtO2 and intracranial pressure bolt inserted following resuscitation. Using a critical care guide, PbtO2 was optimized. Intravenous nicardipine (5–15 mg/hour) was titrated to systolic BP < 160 mm Hg, diastolic BP < 90 mm Hg, mean arterial BP (MABP) 90–110 mm Hg, and PbtO2 > 20 mm Hg. Physiological parameters—intracranial pressure, PbtO2, central venous pressure, systolic BP, diastolic BP, MABP, fraction of inspired O2, and cerebral perfusion pressure (CPP)—were compared before infusion, at 4 hours, and at 8 hours using a t-test.

Results

Sixty episodes of hypertension were reported in 30 patients (traumatic brain injury in 13 patients; aneurysmal subarachnoid hemorrhage in 11; intracerebral and intraventricular hemorrhage in 3 and 1, respectively; arteriovenous malformation in 1; and hypoxic brain injury in 1). Nicardipine was effective in 87% of the patients (with intravenous β blockers in 4 patients), with a 19.7% reduction in mean 4-hour MABP (115.3 ± 13.1 mm Hg preinfusion vs 92.9 ± 11.40 mm Hg after 4 hours of therapy, p < 0.001). No deleterious effect on mean PbtO2 was recorded (26.74 ± 15.42 mm Hg preinfusion vs 27.68 ± 12.51 mm Hg after 4 hours of therapy, p = 0.883) despite significant reduction in CPP. Less dependence on normobaric hyperoxia was achieved at 8 hours (0.72 ± 0.289 mm Hg preinfusion vs 0.626 ± 0.286 mm Hg after 8 hours of therapy, p < 0.01). Subgroup analysis revealed that 12 patients had low pretreatment PbtO2 (10.30 ± 6.49 mm Hg), with higher CPP (p < 0.001) requiring hyperoxia (p = 0.02). In this group, intravenous nicardipine resulted in an 83% improvement in 4- and 8-hour PbtO2 levels (18.1 ± 11.33 and 19.59 ± 23.68 mm Hg, respectively; p < 0.01) despite significant reductions in both mean MABP (120.6 ± 16.65 vs 95.8 ± 8.3 mm Hg, p < 0.001) and CPP (105.00 ± 20.7 vs 81.2 ± 15.4 mm Hg, p < 0.001).

Conclusions

Intravenous nicardipine is effective for the treatment of hypertensive neurological emergencies and has no adverse effect on PbtO2.
Modulation of the secondary injury process after spinal cord injury in Bach1-deficient mice by heme oxygenase–1
Authors: Yamada Kiyotaka , Tanaka Nobuhiro , Nakanishi Kazuyoshi , Kamei Naosuke , Ishikawa Masakazu , Mizuno Toshiyuki , Igarashi Kazuhiro , Ochi Mitsuo
Published: November 2008

Object

Oxidative stress contributes to secondary injury after spinal cord injury (SCI). The expression of heme oxygenase-1 (HO-1), which protects cells from various insults including oxidative stress, is upregulated in injured spinal cords. Mice deficient in Bach1 (Bach1−/−), a transcriptional repressor of the HO-1 and beta-globin genes, express high levels of HO-1 mRNA and protein in various organs. The authors hypothesized that HO-1 modulates the secondary injury process after SCI in Bach1−/− mice.

Methods

Male C57BL/6 (wild-type) and homozygous Bach1−/− C57BL/6 mice were subjected to moderate SCI, and differences in hindlimb motor function, and electrophysiological, molecular biological, and histopathological changes were assessed for 2 weeks.

Results

Functional recovery was greater, and motor evoked potentials were significantly larger in Bach1−/− mice than in wild-type mice throughout the observation period. The expression of HO-1 mRNA in the spinal cord was significantly increased in both mice until 3 days after injury, and it was significantly higher in Bach1−/− mice than in wild-type mice at every assessment point. Histological examination using Luxol fast blue staining at 1 day after injury showed that the injured areas were smaller in Bach1−/− mice than in wild-type mice. The HO-1 immunoreactivity was not detected in uninjured spinal cord, but 3 days postinjury the number of HO-1–immunoreactive cells was obviously higher in the injured area in both mice, particularly in Bach1−/− mice. The HO-1 was primarily induced in microglia/macrophage in both mice.

Conclusions

These results suggest that HO-1 modulates the secondary injury process, and high HO-1 expression may preserve spinal cord function in the early stages after SCI in Bach1−/− mice. Treatment that induces HO-1 expression at these early stages may preserve the functional outcome after SCI.
Thoracic intramedullary melanocytoma with long-term follow-up
Authors: Chacko Geeta , Rajshekhar Vedantam
Published: November 2008

Melanocytomas are tumors of the neuraxis seen predominantly in adults. The authors report a case of a thoracic intramedullary melanocytoma with long-term follow-up of 8 years postsurgery. Melanocytomas, although rare, must be included in the differential diagnosis of intramedullary spinal cord tumors.
Growth and Mycotoxin Production by Chaetomium globosum Is Favored in a Neutral pH
Authors: Fogle Matthew  R. , Douglas David  R. , Jumper Cynthia  A. , Straus David  C.
Published: November 2008

Chaetomium globosum is frequently isolated in water-damaged buildings and produces two mycotoxins called chaetoglobosins A and C when cultured on building material. In this study, the influence of ambient pH on the growth of C. globosum was examined on an artificial medium. This fungus was capable of growth on potato dextrose agar ranging in pH from 4.3 to 9.4 with optimal growth and chaetoglobosin C production occurring at a neutral pH. In addition, our results show that sporulation is favored in an acidic environment.
Time–frequency higher‐order spectra with adjustment to the instantaneous frequency variation
Authors: Gelman L. , Petrunin I.
Published: November 2008

Novel time–frequency techniques are proposed: the short time instantaneous higher‐order spectra (HOS) with adjustment to measured or knowna prioritime variation of the instantaneous frequency of transient signals. It is shown that the proposed transforms are more effective than the non‐instantaneous HOS (i.e. without adjustment to time variation of the instantaneous frequency) in recognizing a non‐stationary nonlinearity. Copyright © 2008 John Wiley & Sons, Ltd.
American college of rheumatology quality indicators for rheumatoid arthritis: Benchmarking, variability, and opportunities to improve quality of care using the electronic health record
Authors: Adhikesavan Leena G. , Newman Eric D. , Diehl Mark P. , Wood G. Craig , Bili Androniki
Published: November 2008

Objective

To measure how rheumatologists across our health system performed with the American College of Rheumatology (ACR) quality indicators (QIs) for rheumatoid arthritis (RA) and methotrexate (MTX) drug safety, and to develop opportunities for improvement.

Methods

An electronic health record (EHR) review of 1,062 unique RA patients seen by 15 rheumatologists in a 1‐year period was performed. Percentage of each QI met, reasons why the metric was not met, and performance of rheumatologists based on years of experience were evaluated.

Results

The percentage met was high for QI‐2 (RA disease‐modifying antirheumatic drug use; 94%), QI‐3 (intervention if RA worse; 85%), and QI‐4 (MTX risks discussion; 87%). Percentage met was lower for QI‐1 (RA core data set; 69%), QI‐5 (MTX baseline studies; 41%), and QI‐6 (MTX followup studies; 46%). QI‐1 and QI‐5 were low due to most physicians missing a single test, and QI‐6 was low because of few physicians driving the percentage down. Better QI performance was seen in rheumatologists with ≤10 years versus >10 years of experience for QI‐1 (90% versus 64%; odds ratio [OR] 4.21, P = 0.004) and QI‐3 (96% versus 82%; OR 4.47, P = 0.019). EHR chart review for this population required 179.3 hours.

Conclusion

Measurement allows us to better understand the quality of care that we deliver. In this systematic benchmarking of the ACR QIs in a large RA cohort, performance was excellent in RA treatment–related QIs. Significant variability was noted in RA and MTX monitoring measures, which can be addressed using process redesign techniques.
Changes in outcome measures for impairment, activity limitation, and participation restriction over two years in osteoarthritis of the lower extremities
Authors: Botha‐Scheepers Stella , Watt Iain , Rosendaal Frits R. , Breedveld Ferdinand C. , Hellio le Graverand Marie‐Pierre , Kloppenburg Margreet
Published: November 2008

Objective

To describe changes in outcome measures in patients with knee and hip osteoarthritis (OA) over 2 years according to the International Classification of Functioning, Disability and Health, and to evaluate the sensitivity to change of available outcome instruments.

Methods

A total of 115 symptomatic knee or hip OA patients (mean age 60.0 years, 80% women) were followed for 2 years. Standardized knee and hip radiographs were scored for joint space narrowing (JSN) using the Osteoarthritis Research Society International Atlas. Pain intensity in knees and hips was graded during physical examination. Self‐reported pain and functioning were assessed with the Western Ontario and McMaster Universities OA Index (WOMAC). Social functioning was assessed with social functioning scores of the RAND 36‐item Health Survey. Standardized response means (SRMs) were calculated to evaluate sensitivity to change.

Results

Substantial increases in JSN and pain intensity total scores over 2 years were observed (SRMs 0.43 and 0.41, respectively). Twenty‐three percent of patients had an increase of at least 1 point in JSN total scores. An increase in pain intensity total scores was present in 46% of patients, whereas a decrease was observed in 19.1.% of patients. WOMAC pain and function scores showed small increases (SRMs 0.15 and 0.18, respectively). No change was seen in social functioning scores (SRM 0.01).

Conclusion

Objective instruments measuring impairment in body structures and function are more sensitive to change over 2 years in patients with OA than self‐reported measurements of impairment in body function, activity limitation, and participation restriction. These findings encourage development of new instruments to improve measurement of disease outcome in OA.
Magnetic resonance imaging, ultrasonography, and conventional radiography in the assessment of bone erosions in juvenile idiopathic arthritis
Authors: Malattia Clara , Damasio Maria Beatrice , Magnaguagno Francesca , Pistorio Angela , Valle Maura , Martinoli Carlo , Viola Stefania , Buoncompagni Antonella , Loy Anna , Ravelli Angelo , Tomà Paolo , Martini Alberto
Published: November 2008

Objective

To compare magnetic resonance imaging (MRI), conventional radiography, and ultrasonography in identifying bone erosions in patients with juvenile idiopathic arthritis (JIA), and to determine the validity and reliability of an MRI scale in detecting and grading joint damage.

Methods

In 26 JIA patients, the clinically more affected wrist was studied with MRI, radiography, and ultrasonography, coupled with standard clinical assessment and biochemical analysis. MR images were assessed independently by 2 readers according to an apposite devised scoring system.

Results

Of 26 patients, 25 (96.1%) had 1 or more erosions as detected by MRI, whereas conventional radiography and ultrasonography revealed erosions in 13 (50%) of 26 and 12 (50%) of 24 patients, respectively. The ability of MRI to detect erosive changes was significantly higher with respect to conventional radiography (P= 0.002 with Bonferroni correction [PB]) and ultrasonography (PB= 0.0002) in the group of patients with <3 years' disease duration. Ultrasonography and conventional radiography were of equivalent value for the detection of destructive changes. Wrist MRI score correlated highly with radiographic erosion score (rs= 0.82) and with wrist limited range of motion score (rs= 0.69). The interreader intraclass correlation coefficient (ICC) for MRI score was excellent (0.97); intrareader ICCs were good for both investigators (0.97 and 0.79).

Conclusion

MRI seems to be a powerful tool to detect early structural damage in JIA. The proposed MRI scale for bone erosions appears promising in terms of reliability and construct validity. The pathophysiologic meaning and the prognostic value of bone erosions revealed only by MRI remain to be established in longitudinal studies.
Oxidative stress: Role of mitochondria and protection by glutathione
Authors: Fernández‐Checa J. C. , García‐Ruiz C. , Colell A. , Morales A. , Marí M. , Miranda M. , Ardite E.
Published: November 2008

Increasing evidence has unraveled a dual functional role of mitochondria as suppliers of the energy required for cell viability, and critical players in the pathway leading to cell death. Consequence of their physiological role in the oxidative phosphorylation is the generation of reactive oxygen species (ROS) as byproducts of the consumption of molecular oxygen in the electron transport chain. Superoxide anion and hydrogen peroxide produced during aerobic respiration are precursors of hydroxyl radical by the participation of transition metals. Glutathione (GSH) in mitochondria is the only defense available to metabolize hydrogen peroxide. A small fraction of the total cellular pool of GSH is sequestered in mitochondria by the action of a carrier that transports GSH from cytosol to the mitochondrial matrix. Recent evidence position mitochondria as subcellular targets of cytokines leading to overproduction of ROS induced by ceramide, a lipid intermediate of cytokine action. Chronic ethanol‐fed cells are selectively depleted of GSH in mitochondria due to a defective operation of the carrier responsible for the transport of GSH from cytosol into the mitochondrial matrix. Its limitation sensitizes alcoholic hepatocytes to the prooxidant effects of cytokines and prooxidants generated by the oxidative metabolism of ethanol. One of the mechanisms leading to the onset of selective defect in the mitochondrial transport of GSH induced by chronic ethanol exposure is mediated by decreased fluidity of the mitochondrial inner membrane. Its fluidization by SAM treatment normalizes the steady state levels of GSH in mitochondria contributing to withstand the oxidative stress derived by the oxidative metabolism of ethanol.
Neuroprotective versus neurodestructive effects of NO‐related species
Authors: Lipton Stuart A. , Choi Yun‐Beom , Sucher Nikolaus J. , Chen H.‐S. Vincent
Published: November 2008

Nitric oxide (NO·) can lead to damaging or protective actions in the central nervous system. Here we consider the chemistry of the NO group and its redox‐related species that can lead to these exactly opposite ends. In the neurodestructive mode, NO· reacts with superoxide anion (O2·−) to form peroxynitrite (ONOO−), which leads to neuronal injury. In contrast, the reaction of the NO group with cysteine sulfhydryls on the NMDA receptor leads to a decrease in receptor/channel activity, avoidance of excessive Ca2+entry, and thus neuroprotection. Site‐directed mutagenesis of recombinant NMDA receptor subunits has recently increased our knowledge of such redox modulation by NO. Transfer of the NO group to cysteine sulfhydryls on the NMDA receptor or other proteins, known as S‐nitrosylation, is becoming recognized as a ubiquitous regulatory reaction, akin to phosphorylation, and represents a form of redox modulation in diverse tissues including the brain.
Experimental diabetic neuropathy: Role of oxidative stress and mechanisms involved
Authors: Martínez‐Blasco Amparo , Bosch‐Morell Francisco , Trenor Carlos , Romero Francisco J.
Published: November 2008

Oxidative stress has been related to the development of diabetic neuropathy. Experimental diabetes (alloxan injection to mice) promotes early biochemical changes in peripheral nervous tissue, e.g., decrease in Na,K‐ATPase activity and glutathione (GSH) peroxidase (GSHPx) activity. The former decrease can be reverted by inhibiting protein kinase C (PKC), since it has been reported that PKC is activated in these experimental conditions. Here we present data demonstrating that the inhibition of PKC, as early as 4 days after alloxan administration, is not able to return to normal values GSHPx activity in sciatic nerve of diabetic mice. Thus, it would fit with our previous proposal of the possible glycation of this protein as an early event in experimental diabetes, and apparently rules out the control of GSHPx activity by PKC in this tissue.
An ethanolic‐aqueous extract of Curcuma longa decreases the susceptibility of liver microsomes and mitochondria to lipid peroxidation in atherosclerotic rabbits
Authors: Quiles J. L. , Aguilera C. , Mesa M. D. , Ramírez‐Tortosa M. C. , Baró L. , Gil A.
Published: November 2008

Atherosclerosis is characterized by oxidative damage which affects lipoproteins, the walls of blood vessels and subcellular membranes. This study evaluates the antioxidant capacity of a Curcuma longa extract on the lipid peroxidation of liver mitochondria and microsome membranes in atherosclerotic rabbits. Male rabbits fed a 3% (w/w) lard and 1.3% (w/w) cholesterol diet were randomly assigned to three groups. Two groups were treated with different dosages of a turmeric extract (A and B) and the third group (control) with a curcumin‐free solution. Basal and in vitro 2,2'‐azobis (2‐amidinopropane) dihydrochloride (AAPH)‐induced hydroperoxide and TBARS productions in liver mitochondria and microsomes were analyzed. Group A had the lowest concentration of mitochondrial hydroperoxides. In microsomes, the basal hydroperoxide levels were similar in all groups but, after the induction of oxidation, group C registered the highest value; TBARS production followed the same trend in mitochondria. These findings suggest that active compounds in curcuma extract may be protective in preventing lipoperoxidation of subcellular membranes in a dosage‐dependent manner.
Ischaemia—reperfusion injury of the liver: treatment in theory and in practice
Authors: Tredger J. Michael
Published: November 2008

Cold ischaemia—reperfusion injuries are an unavoidable feature of current liver transplantation procedures. Damage to liver grafts accures mainly from hypothermic storage under hypoxic conditions (cold ischaemia), from sustained ischaemia during implantation into the recipient (rewarming ischaemia) and from restoration of blood and oxygen to the graft (reperfusion injury). These three stages are characterized by progressive deteriorations in hepatic function, with sinusoidal endothelial cells most affected during cold ischaemia. Activation of Kupffer cells (hepatic macrophages) at reperfusion augments damage to both endothelial and parenchymal cells by the release of numerous compounds which initiate and perpetrate injury and impair the hepatic microcirculation. The key events in the expression of ischaemia—reperfusion injury are detailed and therapeutic interventions are described which target these steps. The treatments discussed include University of Wisconsin (UW) preservation solution, calcium channel blockade, inhibitors of Kupffer cell activation, promoters of microvascular vasodilatation, hepatoprotectants and the use of anti‐oxidants.
Phagocyte‐induced oxidative stress in patients with haemodialysis treatment and organ transplantation
Authors: Lojek A. , Ĉerný J. , Němec P. , Niĉovský J. , Soška V. , Ĉíž M. , Slavíková H. , Kubala L.
Published: November 2008

The aim of the study was to examine the phagocyte‐derived production of reactive oxygen species (ROS), lipoperoxidation and the total radical‐trapping antioxidant parameter (TRAP) in patients undergoing regular haemodialysis (HD) followed by kidney transplantation (n=13). A significant increase in both spontaneous and activated ROS generation was found during the post‐transplantation period in days 1–3. This effect was caused mainly by an increased number of neutrophils. On the other hand, the TRAP parameter was decreased in HD patients. After kidney transplantation, the TRAP parameter increased, reaching the level of healthy controls at the end of the first week after surgery. Increase in MDA level was determined after HD and kidney transplantation. It can be concluded from the results obtained that phagocyte mobilisation and increased oxidative stress after HD and kidney transplantation were associated with the insufficient activity of extracellular antioxidant mechanisms resulting in increased lipid peroxidation.
Mass‐Spectrometric Identification of Anandamide and 2‐Arachidonoylglycerol in Nematodes
Authors: Lehtonen Marko , Reisner Kaja , Auriola Seppo , Wong Garry , Callaway James C.
Published: November 2008

The purpose of the study was to see if nematodes (Caenorhabditis elegans, Caenorhabditis briggsae, and Pelodera strongyloides) produce endocannabinoids; i.e., anandamide (AEA) and 2‐arachidonoylglycerol (2‐AG). In this study, AEA and 2‐AG were identified as endogenous products from nematodes by using electrospray‐ionization ion‐trap MS/MS (ESI‐IT‐MS) experiments operated in the positive‐ionization mode. Endocannabinoids were identified by product ion scan and concentrations were measured by triple quadrupole mass spectrometry in the multiple reaction monitoring mode (MRM). Both AEA and 2‐AG were identified in all of the nematode samples, even though these species lack known cannabinoid receptors. Neither AEA nor 2‐AG were detected in the fat‐3 mutant of C. elegans, which lacks the necessary enzyme to produce arachidonic acid, the fatty acid precursor of these endocannabinoids.
Total Synthesis of desB30 Insulin Analogues by Biomimetic Folding of Single‐Chain Precursors
Authors: Tofteng A. Pernille , Jensen Knud J. , Schäffer Lauge , Hoeg‐Jensen Thomas
Published: November 2008

Insulin is a peptide hormone consisting of 51 amino acids in two chains with three disulfide bridges. Human insulin and various analogues are used for the treatment of diabetes and are produced recombinantly at ton scale. Herein, we report the chemical synthesis of insulin by the step‐wise, Fmoc‐based, solid‐phase synthesis of single‐chain precursors with solubilising extensions, which under redox conditions, spontaneously fold with the correct pairing of the three disulfide bridges. The folded, single‐chain, insulin precursors can be transformed into bioactive two‐chain desB30 insulin by the simultaneous removal of the solubilising extension (4–5 residues) and the chain‐bridging C‐peptide (3–5 residues) by employing Achromobacter lyticus protease—a process well‐known from the yeast‐based recombinant production of insulin. The overall yields of synthetic insulins were as much as 6 %, and the synthetic process was straightforward and not labour intensive.
Cooperative Biosynthesis of Trisporoids by the (+) and (−) Mating Types of the Zygomycete Blakeslea trispora
Authors: Schachtschabel Doreen , David Anja , Menzel Klaus‐Dieter , Schimek Christine , Wöstemeyer Johannes , Boland Wilhelm
Published: November 2008

The fungal phylum zygomycota uses trisporic acids (TSAs), a family of apocarotenoids, during sexual reproduction to synchronize and control activity between the mycelial hyphae of opposite mating types. Separate as well as mixed cultures of Blakeslea trispora were systematically supplemented with putative, deuterium‐labeled precursors downstream of β‐carotene en route to the bioactive TSAs. Analysis of the isolated metabolites allowed the reconstruction of the complete biosynthetic sequence between the first apocarotenoid, D'orenone (1), and the different series of TSAs B (8) and C (13). Both mating types produced a similar spectrum of early metabolites upstream of trisporols B (7) and C (12), while only the (+) type was able to further oxidize trisporols B (7) and C (12) to the corresponding methyltrisporoid B (5) and C (11), respectively. A novel 4‐dihydrotrisporic acid B (14) that was not formed from the labeled precursors was isolated from mated strains; this compound might be derived from oxygenated β‐carotene by a parallel pathway. The ester accumulated in the culture broth of the (+) strain and was only hydrolyzed by mycelia of the (−) strain; this corresponds to a synchronization of the biosynthetic activities of both mating types.
Multi‐block methods in multivariate process control
Authors: Kohonen Jarno , Reinikainen Satu‐Pia , Aaljoki Kari , Perkiö Annikki , Väänänen Taito , Höskuldsson Agnar
Published: November 2008

In chemometric studies all predictor variables are usually collected in one data matrix X. This matrix is then analyzed by PLS regression or other methods. When data from several different sub‐processes are collected in one matrix, there is a possibility that the effects of some sub‐processes may vanish. If there is, for instance, mechanic data from one process and spectral data from another, the influence of the mechanic sub‐process may not be detected. An application of multi‐block (MB) methods, where the X‐data are divided into several data blocks is presented in this study. By using MB methods the effect of a sub‐process can be seen and an example with two blocks, near infra‐red, NIR, and process data, is shown. The results show improvements in modelling task, when a MB‐based approach is used. This way of working with data gives more information on the process than if all data are in one X‐matrix. The procedure is demonstrated by an industrial continuous process, where knowledge about the sub‐processes is available and X‐matrix can be divided into blocks between process variables and NIR spectra. Copyright © 2008 John Wiley & Sons, Ltd.
RNA Aptamers That Reversibly Bind Photoresponsive Azobenzene‐Containing Peptides
Authors: Hayashi Gosuke , Hagihara Masaki , Nakatani Kazuhiko
Published: November 2008

Modulation of biological networks assembled by diverse interactions among biologically active molecules has provided a platform for innovative biotechnologies. Here, we report RNA aptamers that bind to a photoresponsive peptide (KRAzR; Lys‐Arg‐azobenzene‐Arg) containing azobenzene chromophore, which can change its structure by photoirradiation. Aptamers were identified after 10 cycles of an in vitro selection procedure starting with a DNA library containing a 70 nt random region. Surface plasmon resonance (SPR) analysis demonstrated that interactions between aptamers and KRAzR were fully controlled by appropriate photoirradiation to the SPR sensor chip. Upon irradiation of 360 nm on the KRAzR‐immobilized surface, the binding of each aptamer to the surface was significantly decreased. Subsequent photoirradiation of the same surface with 430 nm restored the aptamer binding to the surface. We also observed that direct photoirradiation of the aptamer–peptide complex on a gold surface actively promoted dissociation of the complex. Furthermore, a doped reselection method was applied to acquire structural and sequence information of aptamer 66. From a data analysis of the conserved region and the mutation frequency, we were able to select a plausible secondary structure among three candidates predicted by computational folding simulation.
Enhancing Intermolecular Benzoyl‐Transfer Reactivity in Crystals by Growing a “Reactive” Metastable Polymorph by Using a Chiral Additive
Authors: Murali Chebrolu , Shashidhar Mysore S. , Gonnade Rajesh G. , Bhadbhade Mohan M.
Published: November 2008

Racemic 2,4‐di‐O‐benzoyl‐myo‐inositol‐1,3,5‐orthoacetate, which normally crystallizes in a monoclinic form (form I, space group P21/n) could be persuaded to crystallize out as a metastable polymorph (form II, space group C2/c) by using a small amount of either D‐ or L‐ 2,4‐di‐O‐benzoyl‐myo‐inositol‐1,3,5‐orthoformate as an additive in the crystallization medium. The structurally similar enantiomeric additive was chosen by the scrutiny of previous experimental results on the crystallization of racemic 2,4‐di‐O‐benzoyl‐myo‐inositol‐1,3,5‐orthoacetate. Form II crystals can be thermally transformed to form I crystals at about 145 °C. The relative organization of the molecules in these dimorphs vary slightly in terms of the helical assembly of molecules, that is, electrophile (El)⋅⋅⋅nucleophile (Nu) and CH⋅⋅⋅π interactions, but these minor variations have a profound effect on the facility and specificity of benzoyl‐group‐transfer reactivity in the two crystal forms. While form II crystals undergo a clean intermolecular benzoyl‐group‐transfer reaction, form I crystals are less reactive and undergo non‐specific benzoyl‐group transfer leading to a mixture of products. The role played by the additive in fine‐tuning small changes that are required in the molecular packing opens up the possibility of creating new polymorphs that show varied physical and chemical properties. Crystals of D‐2,6‐di‐O‐benzoyl‐myo‐inositol‐1,3,5‐orthoformate (additive) did not show facile benzoyl‐group‐transfer reactivity (in contrast to the corresponding racemic compound) due to the lack of proper juxtaposition and assembly of molecules.
Direct Zincation of Functionalized Aromatics and Heterocycles by Using a Magnesium Base in the Presence of ZnCl2
Authors: Dong Zhibing , Clososki Giuliano C. , Wunderlich Stefan H. , Unsinn Andreas , Li Jinshan , Knochel Paul
Published: November 2008

A wide range of polyfunctional aryl and heteroaryl zinc reagents were efficiently prepared in THF by using (TMP)2Mg⋅2 LiCl (TMP=2,2,6,6‐tetramethylpiperamidyl) in the presence of ZnCl2. The possible pathways of this metalation procedure as well as possible reactive intermediates are discussed. This experimental protocol expands the tolerance of functional groups and allows an efficient zincation of sensitive heterocycles such as quinoxaline or pyrazine. The zincated arenes and heteroarenes react with various electrophiles providing the expected products in 60–95 % yield.
Pyrrolidinium Ionic Liquid Crystals
Authors: Goossens Karel , Lava Kathleen , Nockemann Peter , Van Hecke Kristof , Van Meervelt Luc , Driesen Kris , Görller‐Walrand Christiane , Binnemans Koen , Cardinaels Thomas
Published: November 2008

N‐Alkyl‐N‐methylpyrrolidinium cations have been used for the design of ionic liquid crystals, including a new type of uranium‐containing metallomesogen. Pyrrolidinium salts with bromide, bis(trifluoromethylsulfonyl)imide, tetrafluoroborate, hexafluorophosphate, thiocyanate, tetrakis(2‐ thenoyltrifluoroacetonato)europate(III) and tetrabromouranyl counteranions were prepared. For the bromide salts and tetrabromouranyl compounds, the chain length of the alkyl group CnH2n+1 was varied from eight to twenty carbon atoms (n=8, 10–20). The compounds show rich mesomorphic behaviour: highly ordered smectic phases (the crystal smectic E phase and the uncommon crystal smectic T phase), smectic A phases, and hexagonal columnar phases were observed, depending on chain length and anion. This work gives better insight into the nature and formation of the crystal smectic T phase, and the molecular requirements for the appearance of this highly ordered phase. This uncommon tetragonal mesophase is thoroughly discussed on the basis of detailed powder X‐ray diffraction experiments and in relation to the existing literature. Structural models are proposed for self‐assembly of the molecules within the smectic layers. In addition, the photophysical properties of the compounds containing a metal complex anion were investigated. For the uranium‐containing mesogens, luminescence can be induced by dissolving them in an ionic liquid matrix. The europium‐containing compound shows intense red photoluminescence with high colour purity.
Thermal Decomposition Modes for Four‐Coordinate Ruthenium Phosphonium Alkylidene Olefin Metathesis Catalysts
Authors: Leitao Erin M. , Dubberley Stuart R. , Piers Warren E. , Wu Qiao , McDonald Robert
Published: November 2008

The four‐coordinate ruthenium phosphonium alkylidenes 1‐Cy and 1‐iPr, differing in the substituent on the phosphorus center, were observed to decompose thermally in the presence of 1,1‐dichloroethylene to produce [H3CPR3][Cl]. The major ruthenium‐containing product was a trichloro‐bridged ruthenium dimer that incorporates the elements of the 1,1‐dichloroethylene as a dichlorocarbene ligand and a styrenic vinyl group on the supporting NHC ligand. Spectroscopic, kinetic, and deuterium‐labeling experiments probed the mechanism of this process, which involves a rate‐limiting C–H activation of an NHC mesityl ortho methyl group. These studies provide insight into intrinsic decomposition processes of active Grubbs type olefin metathesis catalysts, pointing the way to new catalyst design directions.
Selective Benzylic and Allylic Alkylation of Protic Nucleophiles with Sulfonamides through Double Lewis Acid Catalyzed Cleavage of sp3 Carbon–Nitrogen Bonds
Authors: Liu Cong‐Rong , Li Man‐Bo , Yang Cui‐Feng , Tian Shi‐Kai
Published: November 2008

The acid‐catalyzed benzylic and allylic alkylation of protic nucleophiles is fundamentally important for the formation of carboncarbon and carbonheteroatom bonds, and it is a formidable challenge for benzylic and allylic amine derivatives to be used as the alkylating agents. Herein we report a highly efficient benzylic and allylic alkylation of protic carbon and sulfur nucleophiles with sulfonamides through double Lewis acid catalyzed cleavage of sp3 carbon–nitrogen bonds at room temperature. In the presence of a catalytic amount of inexpensive ZnCl2‐TMSCl (TMSCl: chlorotrimethylsilane), 1,3‐diketones, β‐keto esters, β‐keto amides, malononitrile, aromatic compounds, thiols, and thioacetic acid can couple with a broad range of tosyl‐activated benzylic and allylic amines to give diversely functionalized products in good to excellent yields and with high regioselectivity. Furthermore, the cross‐coupling reaction of 1,3‐dicarbonyl compounds with benzylic propargylic amine derivatives has been successfully applied to the one‐step synthesis of polysubstituted furans and benzofurans.
Size‐ and Distance‐Dependent Nanoparticle Surface‐Energy Transfer (NSET) Method for Selective Sensing of Hepatitis C Virus RNA
Authors: Griffin Jelani , Singh Anant Kumar , Senapati Dulal , Rhodes Patsy , Mitchell Kanieshia , Robinson Brianica , Yu Eugene , Ray Paresh Chandra
Published: November 2008

We report size‐ and distance‐dependent surface‐energy transfer (SET) properties of gold nanoparticles for recognizing hepatitis C virus (HCV) RNA sequence sensitively and selectively (single‐base mutations) in a homogeneous format. We have demonstrated that quenching efficiency increases by three orders of magnitude, as the particle size increases from 5 to 70 nm. Due to this extraordinarily high KSV, nanoparticle SET (NSET) detection limit can be as low as 300 fM concentration of RNA, depending on the size of gold nanoparticle. We have shown that the distance‐dependent quenching efficiency is highly dependent on the particle size and the distance at which the energy‐transfer efficiency is 50 %, ranges all the way from 8 nm, which is very close to the accessible distance of conventional Förster resonance energy transfer (FRET), to about 40 nm by choosing gold nanoparticles of different diameters. Our result points out that dipole‐to‐metal‐particle energy transfer and NSET models provide a better description of the distance dependence of the quenching efficiencies for 8 nm gold nanoparticle, but agreement is poor for 40 and 70 nm gold nanoparticles, for which the measured values were always larger than the predicted ones.