bluuebunny/crossref_metadata_2025 huggingface dataset:
Limited Open Reduction and Stabilization of Sacroiliac Fracture‐Luxations Using Fluoroscopically Assisted Placement of a Trans‐Iliosacral Rod in Five Dogs
Authors: LEASURE CHRISTOPHER S. , LEWIS DANIEL D. , SEREDA COLIN W. , MATTERN KARA L. , JEHN CARL T. , WHEELER JASON L.
Published: September 2007

Objective— To describe percutaneous fluoroscopically assisted placement of a trans‐iliosacral rod to stabilize sacroiliac fracture‐luxations after limited open reduction.

Study Design— Retrospective clinical case series.

Animals— Dogs (n=5) with sacroiliac fracture‐luxations.

Methods— Medical records and radiographs were reviewed to evaluate implant placement, fracture reduction, pelvic canal diameter ratio, maintenance of reduction, implant stability, assessment of union, and to identify any complications. Owners were contacted to obtain long‐term assessment of limb function.

Results— Dogs weighed between 6 and 31 kg. Trans‐iliosacral rods were placed correctly traversing the sacral body. Mean (±SD) percent reduction of the sacroiliac joint was 92.9±6.6%. Pelvic canal diameter ratio did not differ significantly between time periods. With the exception of 1 dog, which died in the early postoperative period, all sacroiliac fracture‐luxations healed without appreciable complications. Three dogs were sound and 1 dog had a subtle lameness at final physical and radiographic examination (mean±SD: 217±205 days). Owners assessed their dog's limb function (mean±SD: 355±205 days) as good or excellent.

Conclusions— Trans‐iliosacral rods can be accurately placed using intraoperative fluoroscopy after limited open reduction of sacroiliac fracture‐luxations. Trans‐iliosacral rods provided bilateral secure fixation, allowed early weight‐bearing and dogs consistently had good long‐term clinical results.

Clinical Relevance— Trans‐iliosacral rods are suitable implants for the stabilization of sacroiliac fracture‐luxations, particularly in dogs with bilateral fracture‐luxations and/or concurrent musculoskeletal injuries.
Comparison of99mTcO4−Trans‐Splenic Portal Scintigraphy with Per‐Rectal Portal Scintigraphy for Diagnosis of Portosystemic Shunts in Dogs
Authors: SURA PATRICIA A. , TOBIAS KAREN M. , MORANDI FEDERICA , DANIEL GREGORY B. , ECHANDI RITA L.
Published: September 2007

Objective—To evaluate trans‐splenic portal scintigraphy (TSPS) and per‐rectal portal scintigraphy (PRPS) for diagnosis of congenital portosystemic shunts (CPSS) in dogs, and compare these results with surgical findings.

Study Design—Prospective, randomized cross over clinical trial.

Animals—Dogs (n=42) with suspected CPSS.

Methods—Dogs had TSPS and PRPS 48 hours apart; quantity of radionuclide administered was recorded. Three independent, blinded reviewers evaluated each scintigraphic study for study quality, shunt presence, number, and location of shunt termination (caudal vena cava, azygos vein). All dogs had exploratory celiotomy. Negative scintigraphic findings were confirmed with intraoperative mesenteric portography. Ameroid constrictors were placed on all extrahepatic CPSS, and hepatic biopsies were obtained.

Results—TSPS was 100% sensitive and specific for diagnosis of CPSS and significantly (P<.05) more likely than PRPS to detect shunt number and termination. Interpretation was consistent between observers, and TSPS required significantly less radionuclide than PRPS.

Conclusion—TSPS was as sensitive as PRPS for detection of shunting vessels, and consistently yielded studies of higher quality, allowing detection of shunt number and location with consistent interpretation among radiologists.

Clinical Relevance—TSPS provides information about shunt number and location, which allows improved surgical planning. Because it requires significantly less radionuclide, TSPS improves safety, allows for more comprehensive patient care, and earlier surgical intervention.
Cosmetic Rostral Nasal Reconstruction After Nasal Planum and Premaxilla Resection: Technique and Results in Two Dogs
Authors: GALLEGOS JAVIER , SCHMIEDT CHAD W. , McANULTY JONATHAN F.
Published: September 2007

Objective— To describe a novel reconstructive technique after nasal planum and premaxilla resection.

Study Design— Case report.

Animals— Dogs (n=2) with squamous cell carcinoma (SCC) of the nasal planum.

Methods— A 9‐year‐old neutered female Labrador retriever (dog 1) and an 11–year‐old neutered male Golden retriever (dog 2) had resection of the nasal planum and premaxilla for treatment of locally invasive SCC. Reconstruction of a nasal planum facsimile was based on use of the nonhaired pigmented margins of bilateral labial mucocutaneous rotation‐advancement flaps.

Results— Reconstruction of the premaxilla by construction of a nasal planum facsimile resulted in uncomplicated wound healing and improved cosmesis. There was no tumor recurrence at 1290 (dog 1) and 210 (dog 2) days after surgery.

Conclusion— Reconstruction of a nasal planum facsimile was successfully performed without complications in 2 dogs with high owner satisfaction with cosmetic appearance.

Clinical Relevance— This technique represents a significant advancement in surgical cosmetic outcome, may potentially reduce postoperative complications, and should be considered for dogs requiring nasal reconstruction after nasal planum resection with premaxillectomy.
Radiographic Measurement of the Proximal and Distal Mechanical Joint Angles in the Canine Tibia
Authors: DISMUKES DAVID I. , TOMLINSON JAMES L. , FOX DEREK B. , COOK JAMES L. , SONG KUG JU EDDIE
Published: September 2007

Objective—To describe a method for radiographic measurement of proximal and distal mechanical joint angles of the canine tibia. Normal ranges were established for a population of dogs, and specifically, Labrador retrievers, with cranial cruciate ligament rupture.

Study Design—Retrospective study.

Sample Population—Tibiae (n=105) of dogs evaluated for cranial cruciate ligament rupture; 70 tibiae were from Labrador retrievers, 35 tibiae were from other breeds.

Methods—Anatomic landmarks were established and craniocaudal radiographs were used to measure the mechanical medial proximal (mMPTA) and distal (mMDTA) tibial angles in the frontal plane.

Results—Means (±SD) for all tibiae were mMPTA, 93.30±1.78°, and mMDTA, 95.99±2.70°. For Labrador retrievers, means were mMPTA, 93.38±1.81°, and mMDTA 96.34±2.51°. No significant differences were detected between Labrador Retrievers and non‐Labrador retrievers with respect to mMPTA (power=0.5) or mMDTA (power=0.342). Labrador Retrievers were significantly younger than non‐Labradors (P=.003).

Conclusion—A method for measurement of the mechanical joint angles of the canine tibia in the frontal plane was established and reference ranges for a population of dogs and Labrador Retrievers with cranial cruciate ligament rupture are reported.

Clinical Relevance—The established method of measurement and references ranges can be used to aid in diagnosis, determining indications, and surgical planning for angular limb deformities of the tibia, especially when affected bilaterally. The methodology and reference values may also be used for postoperative critique.
Electrical Transport Properties of La2CuO4 Ceramics Processed by the Spark Plasma Sintering
Authors: Lin Yuan‐Hua , Liu Yong , Zhang Bo‐Ping , Nan Ce‐Wen , Li Jing‐Feng , Shen Zhijian
Published: September 2007

Highly dense La2CuO4 ceramics have been prepared by the spark plasma sintering technique. Temperature dependence of electrical conductivity indicates that La2CuO4 ceramics sintered at over 875°C exhibit a metal‐like behavior, which should be ascribed to the special La2CuO4 crystal structure and its correlation splitting of the half‐filled dx2−y2 band. Our experimental data indicate that all of the La2CuO4 samples exhibit positive thermoelectric power in the whole measuring temperature range, indicating that the majority of charge carriers are holes. It is desirable to obtain good thermoelectric performance for this system by optimizing the electrical properties and reducing the thermal conductivity.
Hydraulic Alumina Binder for Extrusion of Alumina Ceramics
Authors: Nagaoka Takaaki , Duran Cihangir , Isobe Toshihiro , Hotta Yuji , Watari Koji
Published: September 2007

The present work describes the effect of hydraulic alumina (HA) as a new inorganic binder on extrusion of alumina ceramics. The addition of a small amount of HA imparted significant flowability and rigidity to the extruded alumina. Under optimum processing conditions such as amounts of HA and water, and curing period, alumina rods and tubes were successfully extruded using a single screw extruder. Sintered specimens have achieved a relative density of 97% after sintering at 1600°C for 2 h. Dense alumina samples prepared using organic and inorganic binders had similar mechanical properties, that is, Young's modulus >380 GPa and Hv>2000. These results suggest that HA is a new kind of inorganic binder applicable to the extrusion of ceramics.
Semi‐Empirical Technique for Computation of Glass Density
Authors: Loucks Roger J. , Mauro John C. , Tandia Adama , Timofeev Nikolay T.
Published: September 2007

We present a semi‐empirical technique for computation of glass density based on the enthalpy landscape approach. The technique incorporates thermal history and entropy effects into a scaling factor, which is determined using a computed enthalpy versus volume curve and a single experimental density value. We demonstrate the technique on a series of calcium aluminosilicate glasses.
Microstructure and High‐Temperature Corrosion Behavior of a Cr–Al–C Composite
Authors: Lin Zhijun , Li Meishuan , Wang Jingyang , Zhou Yanchun
Published: September 2007

A Cr–Al–C composite was successfully synthesized by a hot‐pressing method using Cr, Al, and graphite as starting materials. X‐ray diffraction, scanning electron microscopy, and transmission electron microscopy analyses revealed that the composite contained Cr2AlC, AlCr2, Al8Cr5, and Cr7C3. The orientation relationships and atomic‐scale interfacial microstructures among Cr2AlC, AlCr2, and Al8Cr5 are presented. This composite displays both excellent high‐temperature oxidation resistance in air and hot‐corrosion resistance against molten Na2SO4 salt. The parabolic rate constants for the oxidation in air at 1000°, 1100°, and 1200°C are 3.0 × 10−12, 6.2 × 10−11, and 6.2 × 10−10 kg2 (m4·s)−1, respectively, while the linear weight gain rates for the hot corrosion of Na2SO4‐coated samples at 900° and 1000°C are, respectively, 1.2 × 10−3 and 4.4 × 10−3 mg (cm2·h)−1. The mechanism of the excellent high‐temperature corrosion resistance can be attributed to the formation of a protectively alumina‐rich scale.
ZnO with Additions of Fe2O3: Microstructure, Defects, and Fe Solubility
Authors: Köster‐Scherger Oliver , Schmid Herbert , Vanderschaeghe Nicole , Wolf Frank , Mader Werner
Published: September 2007

Zinc oxide (ZnO) crystals with additions of iron (III) oxide exhibit a characteristic inversion domain microstructure with domain boundaries on two different habit planes: parallel to {0001} basal planes and parallel to {2115} pyramidal planes of ZnO. The structural inversion of the domains is proved by electron diffraction experiments. In the present transmission electron microscopy study, emphasis is placed on the early stages of domain formation in sintered polycrystalline material and in diffusion couples with single crystals of ZnO. For solute iron content >0.5 at.% of the cations, defects nucleate at the surface and in the interior of ZnO grains at >900°C. These primary defects propagate along the basal planes of ZnO and gradually widen in the positive c‐axis direction of the ZnO host crystal. The widening along c is promoted by a second defect on {211l} planes that moves away from the basal plane defect. The c‐axis orientation in the ZnO region swept by the second defect is inverted, finally resulting in the inversion domain microstructure. A low iron content ≈0.1 at.% was measured in the inverted domains. Energy‐filtered imaging and quantitative electron energy‐loss spectroscopy show that the inversion domain boundaries (IDBs) parallel to the basal planes contain a full close‐packed monolayer of iron whereas the pyramidal IDBs are occupied by iron with ≈2/3 of the content of the basal IDB. Based on experimental observations and arguments of structural chemistry, a mechanism is proposed explaining the nucleation and oriented growth of the inversion domains that are finally induced and driven by the trivalent iron ions at octahedral sites in the primary defects.
Melatonin inhibits nicotinic currents in cultured rat cerebellar granule neurons
Authors: Lax Pedro
Published: September 2007

Abstract: There is limited data regarding the effects of melatonin on the activity of neuronal acetylcholine receptors (nAChRs) themselves. This study analyzes the effects of low concentrations of melatonin on nicotine‐evoked currents from cerebellar granule neurons (CGNs) in culture. Using electrophysiological and Ca2+‐imaging techniques, it was found a subset of rat CGNs to which nicotine application elicited both intracellular Ca2+transients and inward whole‐cell currents. These responses were mediated by heteromeric nAChRs, as assessed by their sensitivity to nicotine and time constant of current decay. Preincubating the cells with low melatonin concentrations (down to 1 pm) significantly reduced the current amplitude in a dose‐dependent manner, without affecting the receptor’s apparent affinity and voltage‐dependency, nor the current’s rise and decay time course. The inhibitory effect of melatonin was significantly reduced by luzindole, a competitive antagonist of both MT1and MT2melatonin receptors. In conclusion, melatonin inhibits nicotinic currents through non‐α7 heteromeric nAChRs expressed by CGNs in culture, an effect that appears to be at least partially mediated by melatonin membrane receptors. Direct modulation of nicotinic receptors is accomplished at doses that are likely to be physiologically relevant, thus providing a mechanism through which melatonin circadian rhythmic levels could modulate cholinergic activity.
The Single Dynamin Family Protein in the Primitive Protozoan Giardia lamblia Is Essential for Stage Conversion and Endocytic Transport
Authors: Gaechter Verena , Schraner Elisabeth , Wild Peter , Hehl Adrian B.
Published: September 2007

Dynamins are universally conserved large guanosine triphosphatases, which function as mechanoenzymes in membrane scission. The primitive protozoan Giardia lamblia has a single dynamin‐related protein (GlDRP) with an unusual domain structure. Giardia lacks a Golgi apparatus but generates transient Golgi‐like delay compartments dubbed encystation‐specific vesicles (ESVs), which serve to accumulate and mature cyst wall proteins during differentiation to infectious cyst forms. Here, we analyze the function of GlDRP during growth and encystation and demonstrate that it relocalizes from peripheral endosomal–lysosomal compartments to nascent ESVs. We show that GlDRP is necessary for secretion of the cyst wall material and ESV homeostasis. Expression of a dominant‐negative GlDRP variant does not interfere with ESV formation but blocks cyst formation completely prior to regulated exocytosis. GlDRP colocalizes with clathrin at the cell periphery and is necessary for endocytosis of surface proteins to endosomal–lysosomal organelles in trophozoites. Electron microscopy and live cell imaging reveal gross morphological changes as well as functional impairment of the endocytic system in cells expressing the dominant‐negative GlDRP. Thus, giardial DRP plays a key role in two distinct trafficking pathways and in organelle homeostasis, both essential functions for the proliferation of the parasite in the gut and its transmission to a new host.
Hyptis pectinata essential oil: chemical composition and anti‐Streptococcus mutans activity
Authors: Nascimento PFC , Alviano WS , Nascimento ALC , Santos PO , Arrigoni‐Blank MF , De Jesus RA , Azevedo VG , Alviano DS , Bolognese AM , Trindade RC
Published: September 2007

Objectives:  The aim of the present study was to evaluate the anti‐Streptococcus mutans activity of Hyptis pectinata essential oil, and present its promising potential against oral diseases.

Materials and methods:  The essential oil of H. pectinata was obtained by hydrodistillation from dried leaves and analyzed by GC / MS. The effectiveness of this essential oil regarding the antimicrobial activity against several S. mutans strains was investigated by the agar diffusion and microdilution methods, and chlorohexidine was used as a standard control.

Results:  The H. pectinata essential oil exhibited considerable inhibitory effect against either all the clinical isolates obtained from patients’ saliva or the ATCC strains tested, with minimum inhibitory and bactericidal concentrations of 200 μg ml−1. The study also compared the efficiency of the emulsifying agents Tween 20, Tween 80, dimethyl sulfoxide and propylene glycol in H. pectinata essential oil when tested against S. mutans. The data obtained confirmed the better inhibitory effect of the oil when using all tested diluents, although Tween 80 seemed to be more suitable for emulsification.

Conclusion:  According to our results, H. pectinata essential oil can be considered a promising alternative to chlorhexidine for the control of oral bacteria‐related diseases and hygiene.
Hypertension, vascular cognitive disorders and neuroprotection
Authors: Hadjiev Dimiter , Mineva Petya
Published: September 2007

Objective:

The role of the antihypertensive therapy in preventing vascular cognitive disorders in elderly persons without a history of stroke is a matter of debate. This review focuses on cognitive disorders in elderly hypertensive patients.

Methods:

Relevant papers were identified by searches in PubMed from 1946 until February 2007 using the keywords ‘cerebral blood flow autoregulation’, ‘vascular cognitive disorders’, ‘neuroimaging in hypertension’, ‘antihypertensive treatment’ and ‘neuroprotection in cerebral ischemia’.

Results:

Excessive blood pressure lowering in patients with long-standing hypertension may increase the risk of cerebral hypoperfusion, white matter lesions and consequent cognitive decline. White matter lesions have been found in the majority of patients with long-standing hypertension. They correlate with vascular cognitive disorders, particularly impairments of attention and executive function, while memory is relatively preserved. Cerebral small vessel disease in elderly patients should be taken into account when antihypertensive treatment is considered. Renin–angiotensin blockade, some calcium channel blockers and statins are thought to possess neuroprotective action.

Conclusion:

For prevention of cerebral hypoperfusion in elderly hypertensives blood pressure lowering should be cautiously controlled. The increased risk of white matter lesions is an indication for early neuroprotection. The combination of renin–angiotensin blockade or calcium channel blockers with statins may become a promising preventive strategy against cognitive decline in elderly hypertensives. Cerebral white matter protection is a future challenge.
Lending a helping hand, screening chemical libraries for compounds that enhance β‐hexosaminidase A activity in GM2 gangliosidosis cells
Authors: Tropak Michael B. , Mahuran Don
Published: September 2007

Enzyme enhancement therapy is an emerging therapeutic approach that has the potential to treat many genetic diseases. Candidate diseases are those associated with a mutant protein that has difficulty folding and/or assembling into active oligomers in the endoplasmic reticulum. Many lysosomal storage diseases are candidates for enzyme enhancement therapy and have the additional advantage of requiring only 5–10% of normal enzyme levels to reduce and/or prevent substrate accumulation. Our long experience in working with the β‐hexosaminidase (EC 3.2.1.52) isozymes system and its associated deficiencies (Tay‐Sachs and Sandhoff disease) lead us to search for possible enzyme enhancement therapy‐agents that could treat the chronic forms of these diseases which express 2–5% residual activity. Pharmacological chaperones are enzyme enhancement therapy‐agents that are competitive inhibitors of the target enzyme. Each of the known β‐hexosaminidase inhibitors (low µm IC50) increased mutant enzyme levels to ≥ 10% in chronic Tay‐Sachs fibroblasts and also attenuated the thermo‐denaturation of β‐hexosaminidase. To expand the repertoire of pharmacological chaperones to more ‘drug‐like’ compounds, we screened the Maybridge library of 50 000 compounds using a real‐time assay for noncarbohydrate‐based β‐hexosaminidase inhibitors and identified several that functioned as pharmacological chaperones in patient cells. Two of these inhibitors had derivatives that had been tested in humans for other purposes. These observations lead us to screen the NINDS library of 1040 Food and Drug Administration approved compounds for pharmacological chaperones. Pyrimethamine, an antimalarial drug with well documented pharmacokinetics, was confirmed as a β‐hexosaminidase pharmacological chaperone and compared favorably with our best carbohydrate‐based pharmacological chaperone in patient cells with various mutant genotypes.
Active‐site‐specific chaperone therapy for Fabry disease
Authors: Fan Jian‐Qiang , Ishii Satoshi
Published: September 2007

Protein misfolding is recognized as an important pathophysiological cause of protein deficiency in many genetic disorders. Inherited mutations can disrupt native protein folding, thereby producing proteins with misfolded conformations. These misfolded proteins are consequently retained and degraded by endoplasmic reticulum‐associated degradation, although they would otherwise be catalytically fully or partially active. Active‐site directed competitive inhibitors are often effective active‐site‐specific chaperones when they are used at subinhibitory concentrations. Active‐site‐specific chaperones act as a folding template in the endoplasmic reticulum to facilitate folding of mutant proteins, thereby accelerating their smooth escape from the endoplasmic reticulum‐associated degradation to maintain a higher level of residual enzyme activity. In Fabry disease, degradation of mutant lysosomal α‐galactosidase A caused by a large set of missense mutations was demonstrated to occur within the endoplasmic reticulum‐associated degradation as a result of the misfolding of mutant proteins. 1‐Deoxygalactonojirimycin is one of the most potent inhibitors of α‐galactosidase A. It has also been shown to be the most effective active‐site‐specific chaperone at increasing residual enzyme activity in cultured fibroblasts and lymphoblasts established from Fabry patients with a variety of missense mutations. Oral administration of 1‐deoxygalactonojirimycin to transgenic mice expressing human R301Q α‐galactosidase A yielded higher α‐galactosidase A activity in major tissues. These results indicate that 1‐deoxygalactonojirimycin could be of therapeutic benefit to Fabry patients with a variety of missense mutations, and that the active‐site‐specific chaperone approach using functional small molecules may be broadly applicable to other lysosomal storage disorders and other protein deficiencies.
Accumulation of altered aspartyl residues in erythrocyte proteins from patients with Down's syndrome
Authors: Galletti Patrizia , De Bonis Maria Luigia , Sorrentino Alvara , Raimo Marianna , D'Angelo Stefania , Scala Iris , Andria Generoso , D'Aniello Antimo , Ingrosso Diego , Zappia Vincenzo
Published: September 2007

Spontaneous protein deamidation of labile Asn residues, generating l‐isoaspartates and d‐aspartates, is associated with cell aging and is enhanced by an oxidative microenvironment; to minimize the damage, the isoaspartate residues can be ‘repaired’ by a specific l‐isoaspartate (d‐aspartate) protein O‐methyltransferase (PIMT). As both premature aging and chronic oxidative stress are typical features of Down's syndrome (DS), we tested the hypothesis that deamidated proteins may build up in trisomic patients. Blood samples were obtained from children with karyotypically confirmed full trisomy 21 and from age‐matched healthy controls. Using recombinant PIMT as a probe, we demonstrated a dramatic rise of l‐isoaspartates in erythrocyte membrane proteins from DS patients. The content of d‐aspartate was also significantly increased. The integrity of the repair system was checked by evaluating methionine transport, PIMT specific activity, and intracellular concentrations of adenosylmethionine and adenosylhomocysteine. The overall methylation pathway was directly monitored by incubating fresh red blood cells with methyl‐labeled methionine; a three‐fold increase of protein methyl esters was detected in trisomic children. Deamidated species include ankyrin, band 4.1, band 4.2 and the integral membrane protein band 3; ankyrin and band 4.1 were significantly hypermethylated in DS. When DS red blood cells were subjected to oxidative treatment in vitro, the increase of protein deamidation paralleled lipid peroxidation and free radical generation. We observed a similar pattern in Epstein–Barr virus B‐lymphocytes from trisomic patients. In conclusion, our findings support the hypothesis that protein instability at asparagine sites is a biochemical feature of DS, presumably depending upon the oxidative microenvironment. The possible pathophysiological implications are discussed.
Identification, sequencing, and localization of a new carbonic anhydrase transcript from the hydrothermal vent tubeworm Riftia pachyptila
Authors: Sanchez Sophie , Andersen Ann C. , Hourdez Stéphane , Lallier François H.
Published: September 2007

The vestimentiferan annelid Riftia pachyptila forms dense populations at hydrothermal vents along the East Pacific Rise at a depth of 2600 m. It harbors CO2‐assimilating sulfide‐oxidizing bacteria that provide all of its nutrition. To find specific host transcripts that could be important for the functioning of this symbiosis, we used a subtractive suppression hybridization approach to identify plume‐ or trophosome‐specific proteins. We demonstrated the existence of carbonic anhydrase transcripts, a protein endowed with an essential role in generating the influx of CO2 required by the symbionts. One of the transcripts was previously known and sequenced. Our quantification analyses showed a higher expression of this transcript in the trophosome compared to the branchial plume or the body wall. A second transcript, with 69.7% nucleotide identity compared to the previous one, was almost only expressed in the branchial plume. Fluorescent in situ hybridization confirmed the coexpression of the two transcripts in the branchial plume in contrast with the trophosome where only one transcript could be detected. An alignment of these translated carbonic anhydrase cDNAs with vertebrate and nonvertebrate carbonic anhydrase protein sequences revealed the conservation of most amino acids involved in the catalytic site. According to the phylogenetic analyses, the two R. pachyptila transcripts clustered together but not all nonvertebrate sequences grouped together. Complete sequencing of the new carbonic anhydrase transcript revealed the existence of two slightly divergent isoforms probably coded by two different genes.
Switching of the homooligomeric ATP‐binding cassette transport complex MDL1 from post‐translational mitochondrial import to endoplasmic reticulum insertion
Authors: Gompf Simone , Zutz Ariane , Hofacker Matthias , Haase Winfried , van der Does Chris , Tampé Robert
Published: September 2007

The ATP‐binding cassette transporter MDL1 of Saccharomyces cerevisiae has been implicated in mitochondrial quality control, exporting degradation products of misassembled respiratory chain complexes. In the present study, we identified an unusually long leader sequence of 59 amino acids, which targets MDL1 to the inner mitochondrial membrane with its nucleotide‐binding domain oriented to the matrix. By contrast, MDL1 lacking this leader sequence is directed into the endoplasmic reticulum membrane with the nucleotide‐binding domain facing the cytosol. Remarkably, in both targeting routes, the ATP‐binding cassette transporter maintains its intrinsic properties of membrane insertion and assembly, leading to homooligomeric complexes with similar activities in ATP hydrolysis. The physiological consequences of both targeting routes were elucidated in cells lacking the mitochondrial ATP‐binding cassette transporter ATM1, which is essential for biogenesis of cytosolic iron‐sulfur proteins. The mitochondrial MDL1 complex can complement ATM1 function, whereas the endoplasmic reticulum‐targeted version, as well as MDL1 mutants deficient in ATP binding and hydrolysis, cannot overcome the Δatm1 growth phenotype.
Amino acids Thr56 and Thr58 are not essential for elongation factor 2 function in yeast
Authors: Bartish Galyna , Moradi Hossein , Nygård Odd
Published: September 2007

Yeast elongation factor 2 is an essential protein that contains two highly conserved threonine residues, T56 and T58, that could potentially be phosphorylated by the Rck2 kinase in response to environmental stress. The importance of residues T56 and T58 for elongation factor 2 function in yeast was studied using site directed mutagenesis and functional complementation. Mutations T56D, T56G, T56K, T56N and T56V resulted in nonfunctional elongation factor 2 whereas mutated factor carrying point mutations T56M, T56C, T56S, T58S and T58V was functional. Expression of mutants T56C, T56S and T58S was associated with reduced growth rate. The double mutants T56M/T58W and T56M/T58V were also functional but the latter mutant caused increased cell death and considerably reduced growth rate. The results suggest that the physiological role of T56 and T58 as phosphorylation targets is of little importance in yeast under standard growth conditions. Yeast cells expressing mutants T56C and T56S were less able to cope with environmental stress induced by increased growth temperatures. Similarly, cells expressing mutants T56M and T56M/T58W were less capable of adapting to increased osmolarity whereas cells expressing mutant T58V behaved normally. All mutants tested were retained their ability to bind to ribosomes in vivo. However, mutants T56D, T56G and T56K were under‐represented on the ribosome, suggesting that these nonfunctional forms of elongation factor 2 were less capable of competing with wild‐type elongation factor 2 in ribosome binding. The presence of nonfunctional but ribosome binding forms of elongation factor 2 did not affect the growth rate of yeast cells also expressing wild‐type elongation factor 2.
Ferrocyanide − a novel catalyst for oxymyoglobin oxidation by molecular oxygen
Authors: Postnikova G. B. , Moiseeva S. A. , Shekhovtsova E. A. , Goraev E. V. , Sivozhelezov V. S.
Published: September 2007

A comparative study of the rates of ferrocyanide‐catalyzed oxidation of several oxymyoglobins by molecular oxygen is reported. Oxidation of the native oxymyoglobins from sperm whale, horse and pig, as well as the chemically modified (MbO2) sperm whale oxymyoglobin, with all accessible His residues alkylated by sodium bromoacetate (CM‐MbO2), and the mutant sperm whale oxymyoglobin [MbO2(His119→Asp)], was studied. The effect of pH, ionic strength and the concentration of anionic catalyst ferrocyanide, [Fe(CN)6]4–, on the oxidation rate is investigated, as well as the effect of MbO2 complexing with redox‐inactive Zn2+, which forms the stable chelate complex with functional groups of His119, Lys16 and Asp122, all located nearby. The catalytic mechanism was demonstrated to involve specific [Fe(CN)6]4– binding to the protein in the His119 region, which agrees with a high local positive electrostatic potential and the presence of a cavity large enough to accommodate [Fe(CN)6]4– in that region. The protonation of the nearby His113 and especially His116 plays a very important role in the catalysis, accelerating the oxidation rate of bound [Fe(CN)6]4– by dissolved oxygen. The simultaneous occurrence of both these factors (i.e. specific binding of [Fe(CN)6]4– to the protein and its fast reoxidation by oxygen) is necessary for the efficient ferrocyanide‐catalyzed oxidation of oxymyoglobin.
Perfusion, oxygenation and warming
Authors: Leaper David
Published: September 2007

Perfusion, oxygenation and warming are three elements which have a significant effect on wound healing both with respect to speed and quality of healing. The effects include infection control, increased blood flow and improved quality of granulation tissue. The importance of these elements are outlined and discussed to provide and introduce the importance of oxygen in the healing process.
Cu2O/Cu Cermet as a Candidate Inert Anode for Al Production
Authors: Feng L. C. , Shao W. Z. , Zhen L. , Xie N. , Ivanov V. V.
Published: September 2007

Cu2O/xCu (x=0–25 wt%) cermets were evaluated as a novel partially inert anode for aluminum (Al) production. The physical and mechanical properties, including the compressive strength, flexural strength, thermal expansion coefficient, thermal conductivity, and dc electrical conductivity were tested at room temperature and at temperatures up to 950°C. The coefficient of thermal expansion, compressive strength, flexural strength, thermal conductivity, and electrical conductivity of Cu2O/Cu cermets increased with increasing Cu content. High‐temperature electrical conductivity measurements showed that with increasing temperature, the electrical conductivity increased when the Cu content was below the percolation threshold, while it decreased when the Cu content was above the percolation threshold. A relatively stable CuAlO2 layer formed on the cermet surface during electrochemical testing, and the corrosion rate of this anode was estimated to be about 1.8–1.9 cm/year in Al production.
Materials Development for Advanced Planar Solid Oxide Fuel Cells
Authors: Tietz Frank , Fu Qingxi , Haanappel Vincent A. C. , Mai Andreas , Menzler Norbert H. , Uhlenbruck Sven
Published: September 2007

High‐power density and high durability are the main targets for solid oxide fuel cell (SOFC) development at Forschungszentrum Jülich. Power density has been further increased by variation of the material composition of perovskite‐based cathodes (Sr content, Co content, substoichiometry) and by optimization of the diffusion barrier (Gd‐substituted ceria) between an electrolyte and a cathode. The application of dense diffusion barrier layers significantly improved the performance. The associated avoidance of SrZrO3 formation, however, contributed only to a small extent to the improvement of durability of SOFCs with LSCF cathodes. The redox stability of anode‐supported SOFCs has been addressed in two ways: (a) conventional Ni/yttria‐stabilized zirconia anode substrates have been investigated to explore the limits of re‐oxidation and to determine the degree of oxidation at which no damages occur. (b) Alternative anodes and anode substrates are under development, which basically consist of mixed‐conducting ceramics. Avoiding the high amount of nickel decreases the probability of failure, but does not automatically lead to redox‐stable anodes. The differences in the materials' properties of such ceramics in oxidizing and reducing environment are addressed.
Dispersion of Zirconium Diboride in an Aqueous, High‐Solids Paste
Authors: Huang Tieshu , Hilmas Gregory E. , Fahrenholtz William G. , Leu Ming C.
Published: September 2007

The dispersion of ZrB2particles was investigated. In aqueous systems, the surface of ZrB2consists of a thin layer of ZrO2that controls the surface chemistry and surface charge. Measurements showed that the ZrB2had an isoelectric point of pH=4.7 and a maximum ζ potential of −50 mV at pH=9. The addition of a dispersant, either an ionic ammonium polyacrylate or a nonionic alkoxylated polyether, increased the ζ potential of ZrB2by as much as 60 mV to −110 mV. Viscosity measurements were used to optimize dispersant concentrations. High‐solids loading (∼45 vol.% ZrB2) aqueous pastes were prepared with two different dispersants. The pastes had viscosities of 40–50 Pa·s which was acceptable for extrusion, and were used to fabricate three‐dimensional components from ZrB2.
Development, Analysis, and Application of a Glass–Alumina‐Based Self‐Constrained Sintering Low‐Temperature Cofired Ceramic
Authors: Takada Takahiro , Nakao Shuya , Kojima Masaru , Higuchi Yukio
Published: September 2007

The effects of an inner constraint layer and alumina particles on the microstructure, strength, and shrinkage of the laminated low‐temperature cofired ceramic (LTCC) green sheet were investigated. Alumina particles of several sizes were used in the inner‐constraint layer in order to strengthen the LTCC substrate. Smaller alumina particles in the inner‐constraint layer produced a substrate with a high bending strength. Sintering shrinkage in the x–y direction of the LTCC is related to the bending strength of the debinded alumina particle layer used for an inner‐constraint layer. A larger pore size in the inner‐constraint layer was found to increase the distance of the glass penetration from the glass–alumina layer into the inner‐constraint layer. The total thickness of the constraint layer changes the shrinkage in the x–y direction and the bending strength.
System Analysis of a DoD Print Head for Direct Writing of Conductive Circuits
Authors: Cibis Dominik , Krüger Klaus
Published: September 2007

The inkjet‐printing principle is becoming more and more important for new applications besides conventional graphic printing. The target at our institute is to print conductive silver lines and areas of different widths and thicknesses. Based on a drop‐on‐demand (DoD) micro feeding system, a colloidal ink printer was developed to print conductive circuits. The printer has a stationary piezo‐driven print head with a nozzle diameter of 100 μm. With such a nozzle, conductive paths with a width between 110 and 250 μm can be realized. A waveform generator is used to actuate the print head's piezo actuator. The most common control signal is a nearly rectangular voltage pulse. Shape, duration, and amplitude of the piezo control signal influence the stability of the printing process and thus the quality of the printed electrical structures significantly. Different rise and dwell times or pulse shapes can be considered to optimize the printing process. In this article, the piezo control signal's shape is analyzed, varied and the print head's system behavior is characterized. In a performance and signal analysis, the influence of the piezo input signal's shape on the transient behavior of the piezo output energy signal is identified. An optimized piezo control signal shall be achieved. In conclusion, a method is presented to measure droplet parameters such as radius, speed, and volume.
Stochastic simulation of the severity of hydrological drought
Authors: Abebe Adane , Foerch Gerd
Published: September 2007

This study seeks to identify a stochastic model (or models) that can be used for mathematical description, simulation and short‐term forecasting of severity of hydrological drought in the Wabi Shebele river basin, Ethiopia. The drought variables (run sum and run length) are extracted using NIZOWKA after defining a possible truncation level from monthly streamflow data. Hydrologically homogeneous pools in the basin are established using hierarchical clustering using the parameters mean rainfall, temperature, normalized digital vegetation index and stream flow. Thus, five prominent homogeneous pools are developed. Among the regions identified, one at the upstream semi‐humid portion, station 61004, and another at the downstream arid portion, station 63001, were selected for the analysis. Stochastic modelling of the severity of hydrological drought using the Box and Jenkins methodology was carried out at both sites and compared. Diagnostic checks were performed for all the models identified from the autocorrelation function (ACF) and partial autocorrelation function (PACFs) using automatic selection criteria. The stochastic component explains an appreciable proportion of the variance (82–89%) caused in the time series at both locations. The multiplicative seasonal autoregressive integrated moving average (SARIMA) (0, 1, 1) (0, 1, 1)12 outperforms the candidate models considered in adequately capturing the severity of drought in the area. The implications of the analysis for future water management in the basin are also discussed.
Developing an integrated water management strategy to overcome conflicts between urban growth, water infrastructure and environmental quality: a case study from Ashford, Kent
Authors: Furey S. G. , Lutyens B. C.
Published: September 2007

Ashford, in East Kent, is a government‐designated growth area. Between 2001 and 2031, the town is set to grow by 31 000 homes and 28 000 jobs, almost doubling in size. This raises numerous concerns about the ability of the local water infrastructure and Kentish Stour catchment to accept this pressure in the short and long term. The Ashford integrated water management study (AIWMS) set out to address all the issues around water quality, water resources, biodiversity and flood risk to allow Ashford's growth to occur without unacceptable environmental damage. The study reviewed current problems with the water environment, established the key constraints to growth that might arise from the proposed development and identified water management strategies to accommodate Ashford's expansion. The paper reviews the integration methodology that was developed and discusses the lessons learned from the experience.
Suburbanisation of important aquifers in England and Wales: estimating its current extent
Authors: Morris B. , Cunningham J.
Published: September 2007

The UK rate of conversion of rural into suburban land cover will increase as the UK population is projected to rise to 70 million by 2056, household size continues to decline and previously developed land becomes scarcer and less attractive. The resultant change in landuse will significantly impact underlying groundwater resources. Geographical information system (GIS) analysis is used to estimate the current extent of suburbanised land cover overlying locally and nationally important aquifers in England and Wales. The effect on groundwater catchments will be marked in southern, central and eastern England, where high groundwater dependence and intense pressure for new housing will inevitably lead to a rise in suburban land cover on periurban catchments that are currently rural land. Water resource planning implications would be better understood with more catchment‐scale research. Meanwhile, areas of aquifer most likely to urbanise by 2050 and public supplies most vulnerable to the consequent changes need identifying.
Cellular adaptations in soleus muscle during recovery after hindlimb unloading
Authors: Oishi Y. , Ogata T. , Yamamoto K.‐i. , Terada M. , Ohira T. , Ohira Y. , Taniguchi K. , Roy R. R.
Published: September 2007

Aim:  We used a model of chronic unloading followed by reloading to examine the apoptotic responses associated with soleus muscle atrophy and subsequent recovery.

Methods:  Male Wistar rats were subjected to hindlimb unloading (HU) for 2 weeks and subsequent reloading for 0, 3, 7 and 14 days. One‐half of the HU‐reloaded rats were administered cyclosporine A (CsA), a calcineurin (CaN) inhibitor.

Results:  There was fibre atrophy (73%) and a decrease in slow type I fibre/myosin heavy chain (MyHC) composition in the soleus muscle after 2 weeks of HU. Fibre size and type I MyHC composition recovered to near the age‐matched control levels by recovery day 14 in non‐treated, but not in CsA‐treated, rats. Myonuclear number was lower and the number of apoptotic nuclei higher in 2‐week HU than control rats. These values returned to control levels after 7 and 14 days of recovery, respectively, in both HU‐recovery groups. After 2 weeks of HU, the levels of heat shock proteins (Hsp) 60 and 72, mitochondrial cytochrome c oxidase subunit IV (Cox IV), and peroxisome proliferator‐activated receptor gamma coactivator 1 (PGC‐1) proteins were lower than control. The levels of all of these proteins gradually increased to or above the control levels during cage recovery in both groups.

Conclusion:  Our results indicate that apoptotic mechanisms are involved in the modulation of myonuclear number during chronic unloading and subsequent reloading. Furthermore, it appears that CaN is related to fibre size and phenotype adaptations, but not to apoptotic responses.
Media Geographies: Uncovering the Spatial Politics of Images
Authors: Rosati Clayton
Published: September 2007

Geographers are increasingly interested in the study of media. This article thinks through media geographies via a review of the recent literature on media, space, and place. In doing so, it suggests that geographers are situated in a particularly useful place to think about the spatial politics of media and images. But, in order to do so, they must wrestle with some unaddressed issues regarding those politics, particularly regarding the struggles over social power through media and images. It is argued that geographers’ most important contributions to these questions will come from a focus on the spatial processes, terrain, and built environment of these struggles, not just on the images themselves.
Percutaneous Penetration, Melanin Activation and Toxicity Evaluation of a Phytotherapic Formulation for Vitiligo Therapeutic
Authors: Truite Cecília Valente Rodrigues , Philippsen Gisele Strieder , Ueda‐Nakamura Tânia , Natali Maria Raquel Marçal , Filho Benedito Prado Dias , Bento Antonio Carlos , Baesso Mauro Luciano , Nakamura Celso Vataru
Published: September 2007

The aim of this work was to apply photoacoustic spectroscopy for the ex vivo determination of the penetration rate of a phytotherapic formulation for vitiligo therapeutic, with or without salicylic acid as the promoter agent. In addition, the compound toxicity and morphophysiology effects were evaluated for different concentrations of salicylic acid. The experiments were performed as a function of the period of time of treatment in a well‐controlled group of rabbits. Toxic effects were not observed with any of the tested products. All formulations containing salicylic acid induced cutaneous reaction which was dose dependent. The histological analysis showed that the use of the medication was associated with an increased comedogenic effect in relation to the control group, regardless of salicylic acid concentration. Inflammatory reactions and acanthosis were observed only in the animals treated with formulations containing higher concentrations of salicylic acid, while none of these effects were detected with the use of the formulation containing 2.5% (wt/vol) of salicylic acid. Photoacoustic depth monitoring showed that both formulations, with or without salicylic acid, propagated through the skin up to the melanocytes region, suggesting that the transport of the active agent may occur through the epithelial structure without the need of using queratinolitic substances, which are known to induce side effects in the animals.