bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fluorescence Enhancement of Laccase Induced by Reduction of Cu(II) Sites
Authors: Goldberg Michel , Pecht Israel 
Published: May 2006

The intrinsic fluorescence of laccase (
p
-diphenol:O
2
oxidoreductase, EC 1.10.3.2), emitted by its tyrosinyl and tryptophanyl residues, underwent significant enhancement upon reduction of the enzyme redox sites. The increase in quantum yield reached its maximum after the addition of approximately four reduction equivalents and depended on the wavelength of excitation:

54% increase for λ
ex
= 250 nm and 76% for λ
ex
= 305 nm.

A linear correlation between this enhancement and the reduction of the type 1 Cu(II) was observed both by direct measurement and by calculation on the basis of added reductant.
The implications of the fluorescence enhancement and its correlation with the reduction of the type 1 copper are discussed in terms of the possible quenching mechanisms. The possibility of a redox-induced structural transition in the protein is suggested.
The Polypeptide Subunit Structure of the DNA-dependent RNA Polymerase of
Zea mays
Chloroplasts
Authors: Smith H. J. , Bogorad L. 
Published: May 2006

Analysis of the maize chloroplast DNA-dependent RNA polymerase by electrophoresis on polyacrylamide gels that contain sodium dodecyl sulfate shows that the enzyme is multimeric. It contains at least two polypeptides of 180,000 and 140,000 daltons. Polypeptides of lower molecular mass that are associated with the enzyme at several stages of purification may also be subunits of the enzyme.
Electrophoresis of a mixture of purified maize nuclear DNA-dependent RNA polymerase IIA and chloroplast polymerase on sodium dodecyl sulfate-polyacrylamide gels resolves the 160,000 dalton polypeptide of IIA from the 140,000 dalton polypeptide of the chloroplast enzyme, but does not resolve the 180,000 dalton components found in both enzymes. The polypeptides of less than 40,000 daltons in the highly purified maize nuclear IIA preparations are absent from preparations of purified maize chloroplast RNA polymerase.
Membrane Fatty Acid Replacements and Their Effect on Growth and Lectin-Induced Agglutinability
Authors: Horwitz Alan F. , Hatten Mary Elizabeth , Burger Max M. 
Published: May 2006

The growth of 3T3 and SV101 3T3 cells in a lipid-depleted medium is enhanced by the addition of biotin or some fatty acids. The extent of enhancement depends on the fatty acid(s) supplied. The presence of linoleate is unique, since it induces a morphological alteration in 3T3 cells resulting in a cell similar to an SV101-transformed 3T3 cell. Analyses of the fatty acids from the membrane phosphatides show that the exogenously supplied fatty acids are incorporated and alter the fatty acid composition. This is most clearly evident with heptadecanoate-grown cells, in which this fatty acid and its derivatives comprise over 45% of the fatty acids in the phospholipids.
The fatty acid replacements have a striking effect on the temperature dependence of agglutination by wheat germ agglutinin and concanavalin A, implying that fluidity is involved in agglutination. These temperature dependencies and the effect of fatty acid replacements on them were different for the two lectins, but similar for both transformed and untransformed cells. These observations are interpreted as suggesting that the lipid phase is heterogeneous, and that transformed and untransformed cell membranes have regions of similar fluidity.
Temperature sensitivity of cyclic AMP production and catecholamine-induced refractoriness in a rat astrocytoma cell line
Authors: Nickols G. Allen , Brooker Gary 
Published: May 2006

Intracellular cyclic AMP was increased more than 100-fold when rat C6-2B astrocytoma cells were treated with isoproterenol in the cold (4°C). When the cells were treated with the phosphodiesterase inhibitor, 3-isobutyl-1-methylxanthine, and isoproterenol, cyclic AMP levels rose more than 150-fold. The levels achieved compared favorably with the 250-fold increase in cyclin AMP produced by (-)isoproterenol at 37°C.(-)Isoproterenol at 5 nM stimulated half-maximal cyclic AMP production at 4°C and at 37°C and was blocked by (-)propranolol at both temperatures. The concentrations of cyclic AMP attained by these cells after (-)isoproterenol stimulation in the cold may be accounted for, in part, by alterations in the efflux of the nucleotide from the cells since extracellular cyclic AMP, an indicator of cyclic AMP efflux, was found to be dramatically reduced in the cold.
The cells, when exposed to (-)isoproterenol for up to 6 hr at low temperature, maintained normal responsiveness to this agent when rechallenged at 4° or 37°C. Thus, they did not display agonist-induced refractoriness during that period of exposure at 4°C, although refractoriness is always seen within 90 min at 37°C. Refractoriness, once established by (-)isoproterenol treatment at 37°C, was not reversed by exposure of the cells to cold. These data suggest that the development of catecholamine refractoriness requires a temperature-sensitive step that lies distal to the hormone-receptor interaction and cyclic AMP generaton.
NEW DEVICE TO PERFORM COAGULATION AND IRRIGATION SIMULTANEOUSLY DURING ENDOSCOPIC SUBMUCOSAL DISSECTION USING AN INSULATION‐TIPPED ELECTROSURGICAL KNIFE
Authors: Kume Keiichiro , Yamasaki Masahiro , Yoshikawa Ichiro , Otsuki Makoto 
Published: May 2006

Background:  Although bleeding is an unavoidable complication of endoscopic submucosal dissection (ESD), endoscopic hemostasis using an insulation‐tipped electrosurgical knife (IT) knife is impossible because an insulator is mounted at the tip of the knife. We have developed a new type of hood which could perform both coagulation and irrigation simultaneously.Methods:  Our new device was fabricated by drilling a side hole in the cap portion of a conventional transparent hood followed by attaching a machined papillotomy knife to the exterior surface of the hole.Results:  Our new hood was useful for hemorrhage during ESD using IT knife.Conclusions:  With this method, endoscopic hemostasis using IT knife is easy, as hemostatic procedure can be performed under irrigation and coagulation using conventional endoscopy.
Cloning and characterization of the homologous genes of firefly luciferase in the mealworm beetle, Tenebrio molitor
Authors: Oba Y. , Sato M. , Inouye S. 
Published: May 2006

AbstractThree homologous genes of firefly luciferase were cloned from the non‐luminous beetle Tenebrio molitor. Three gene products for homologues, TmLL‐1, TmLL‐2 and TmLL‐3, showed fatty acyl‐coenzyme A (acyl‐CoA) synthetic activity, but not luciferase activity with firefly luciferin. The transcripts were detected through the developmental stages in T. molitor. These results suggested that firefly luciferase was evolved from a fatty acyl‐coenzyme A synthetase by gene duplications in the insect.
The rapid divergence of the ecdysone receptor is a synapomorphy for Mecopterida that clarifies the Strepsiptera problem
Authors: Bonneton F. , Brunet F. G. , Kathirithamby J. , Laudet V. 
Published: May 2006

AbstractIn arthropods, the regulation by ecdysteroids is mediated by the heterodimer between the ecdysone receptor (ECR; NR1H1) and ultraspiracle (USP/RXR; NR2B4) nuclear receptors. Both ECR and USP/RXR ligand‐binding domains experienced a strong acceleration of evolutionary rate in Diptera and Lepidoptera, which belong to the superorder Mecopterida. We performed a phylogenetic analysis of 28 ECR and 30 USP/RXR protein sequences from 36 arthropod species, including representatives from Trichoptera, Mecoptera and Siphonaptera. Our data show that the acceleration of ECR and USP/RXR was a unique event in the ancestor of Mecopterida. Our analysis shows further that Strepsiptera ECR and USP/RXR sequences are unambiguously placed outside of the Mecopterida clade. Protein alignments reveal that eight of 11 synapomorphies support an affinity between Strepsiptera and Coleoptera sequences. The affiliation of Strepsiptera to Diptera should therefore be rejected.
Vulnerable patients with a fractured neck of femur: nutritional status and support in hospital
Authors: Nematy M. , Hickson M. , Brynes A.E. , Ruxton C.H.S. , Frost G.S. 
Published: May 2006

AbstractBackground and aim  Malnutrition has serious consequences for recovery and increases the risk of complications in hospital patients. Fractured neck of femur (NOF) patients may be particularly at risk because of their old age and frail state of health. We conducted an observational study to evaluate the nutritional state and the nutritional support, which was provided to this group during their stay in hospital.Methods  Twenty‐five consecutive people admitted to an orthopaedic ward with a fractured NOF at Charing Cross Hospital, London were recruited. Anthropometric measures, biochemical indices, 3 days dietary intake and dietetic referral rates were collected.Results  Patients had a significantly lower body mass index (BMI) compared with the mean BMI for sex and age in an elderly UK population (21.97 ± 1.06 versus 26.73 ± 0.03 kg m−2; P < 0.005). They took just 58.6% of their energy requirements in hospital (4219 ± 319 versus 7199 ± 202 kJ mean−1 daily intake over 3 days in week 2). Using the hospitals own nutritional risk assessment tool 56% of patients were found to be at risk of malnutrition on admission, which increased to 68% after 2–3 weeks. Of these 64% were referred to a dietitian and were given nutritional supplements. Nutritional assessment revealed that their nutritional status worsened during stay.Conclusions  This group of patients with fractured NOF is likely to be malnourished on admission and to show a rapid deterioration in its nutrition status during admission. Energy needs were not met in up to 50% of patients. These results reinforce the need to screen, supplement and monitor fractured NOF patients.
Culture Medium and Protein Supplementation in the Generation and Maturation of Dendritic Cells
Authors: Royer P.‐J. , Tanguy‐Royer S. , Ebstein F. , Sapede C. , Simon T. , Barbieux I. , Oger R. , Gregoire M. 
Published: May 2006

AbstractDendritic cells (DC) are powerful antigen‐presenting cells that have drawn many attentions due to the recent development of anti‐cancer vaccines. Clinical grade production of monocyte‐derived DC (Mo‐DC) is extensively studied, and many efforts are made to develop and improve clinical standard operating procedures. Most of the parameters involved, such as the cytokines and maturation agents, have been widely assessed. However, very few are investigated about how culture medium and additional protein components affect DC yield, viability and maturation. Thus, our study aimed to compare the impact of standard culture medium on Mo‐DC differentiation and maturation. Commercially available media for hematopoietic cell culture as well as different protein supplementations, that is foetal calf serum (FCS), autologous plasma (AP), human serum (HS) and human serum albumin (HSA) were tested. Culture yields, cell viability and DC maturation were investigated. Differentiation yields were similar between the conditions used. However, we evidenced significant differences in terms of cytotoxicity and DC maturation (phenotypic and functional). This underscores the importance of defining culture medium composition in clinical standard operating procedures to insure quality control, and also when preparing DC for experimental uses.
Laparoscopic‐Assisted Cystotomy for Urolith Removal in Geldings
Authors: RÖCKEN MICHAEL , STEHLE CHRISTIANE , MOSEL GESINE , RASS JULIA , LITZKE LUTZ F. 
Published: May 2006

Objective—To describe a technique for laparoscopic‐assisted removal of cystic calculi in geldings and report outcome.Study Design—Clinical report.Animals—Four geldings with cystic calculi.Methods—Laparoscopic‐assisted cystotomy and urolith retrieval was performed in 4 anesthetized geldings positioned in dorsal recumbency. With a laparoscope portal located at the umbilicus, the abdomen was insufflated and then the surgical table was tilted (30° head‐down position) before an instrumental portal was created parallel and 2–3 cm medial to the left external inguinal ring. Laparoscopic grasping forceps were inserted to grasp the cranial aspect of the bladder and elevate it to the ventral abdominal wall. With the instrumental portal as mid‐point, the parainguinal skin incision was longitudinally extended cranial and caudal (∼8–10 cm) to accommodate the size of the urolith. The apex of the bladder was exteriorized and sharply incised, the urolith extracted, and after cystotomy closure, the bladder was repositioned. The mini‐laparotomy and trocar incisions were closed in layers.Results—There were no intra‐ or post‐operative complications. All horses had minor incisional swelling for 3–4 days. No signs of abdominal or incisional pain were observed. Hematuria and slight stranguria occurred until the 3rd or 4th day. Surgical time (skin incision to skin closure) was 35–40 minutes. On long‐term follow‐up (up to 12 months) no recurrence of clinical signs associated with cystic calculi occurred.Conclusion—Uroliths (6–8 cm diameter) can be removed by laparoscopic‐assisted cystotomy in geldings.Clinical Relevance—Laparoscopic‐assisted cystotomy combines the advantages of the parainguinal laparocystotomy with laparoscopic technique for removal of cystic calculi while avoiding their disadvantages.
Thermodynamics of Void Fraction in Saturated Flow Boiling
Authors: Collado Francisco J. , Monné Carlos , Pascau Antonio , Fuster Daniel , Medrano Andrés 
Published: May 2006

AbstractRecently, Collado (Proc, IMECE 2001, Symposium on Fluid Physics and Heat Transfer for Macro- and Micro-Scale Gas-Liquid and Phase Change Flows) suggested calculating void fraction, an essential element in thermal-hydraulics, working with the “thermodynamic” quality instead of the usual “flow” quality. The “thermodynamic” quality is a state variable, which has a direct relation with the actual vapor volumetric fraction, or void fraction, through phase densities. This approach provides a procedure for predicting void fraction, if values of “thermodynamic” quality are available. However, the standard heat balance is usually stated as a function of the “flow” quality. Therefore, we should search for a new heat balance between the mixture enthalpy, based on “thermodynamic” quality, and the absorbed heat. This paper presents the results of such analysis based on the accurate measurements of the outlet void fraction measured during the Cambridge project by Knights (1960, “A Study of Two-Phase Pressure Drop and Density Determination in a High-Pressure Steam-Water Circuit,” Ph.D. thesis, Cambridge University Engineering Lab, Cambridge, UK) in the 1960s for saturated flow boiling. In the 286 tests analyzed, the pressure and mass fluxes range from 1.72 MPa to 14.48 MPa and from 561.4 to 1833.33 kgm−2s−1, respectively. As the main result, we find that the slip ratio would close this new thermodynamic heat balance. This has allowed the accurate calculation of void fraction from this balance, provided we can predict the slip ratio. Finally, the strong connection of this new thermodynamic heat balance with the standard one through the slip ratio is highlighted.
Knee Angular Impulse as a Predictor of Patellofemoral Pain in Runners
Authors: Stefanyshyn Darren J. , Stergiou Pro , Lun Victor M. Y. , Meeuwisse Willem H. , Worobets Jay T. 
Published: May 2006

Background Identification of mechanical factors associated with patellofemoral pain, the most prevalent running injury, is necessary to help in injury prevention, but unfortunately they remain elusive. Hypothesis Runners who develop patellofemoral pain have increased knee joint angular impulse in the frontal plane. Study Design Case control study; Level of evidence, 3. Methods A retrospective study compared knee abduction impulses of 20 patellofemoral pain patients with those of 20 asymptomatic patients. A second prospective study quantified knee angular impulses during the stance phase of running of 80 runners at the beginning of the summer running season. Epidemiologic data were then collected, recording the type and severity of injury of these runners during a 6-month running period. Results The patellofemoral pain patients in the retrospective study had significantly higher (P =. 026) knee abduction impulses (17.0 ± 8.5 Nms) than did the asymptomatic patients (12.5 ± 5.5 Nms). Six patients developed patellofemoral pain during the prospective study. The prospective data showed that patients who developed patellofemoral pain had significantly higher (P =. 042) knee abduction impulses (9.2 ± 3.7 Nms) than did matched patients who remained uninjured (4.7 ± 3.5 Nms). Conclusion The data indicate that increased knee abduction impulses should be deemed risk factors that play a role in the development of patellofemoral pain in runners. Clinical Relevance Footwear and running style can influence knee angular impulse, and the appropriate manipulation of these variables may play a preventive role for patients who are predisposed to patellofemoral pain.
A novel fibrinogen variant (fibrinogen Seoul II; AαGln328Pro) characterized by impaired fibrin α-chain cross-linking
Authors: Park Rojin , Doh Hyun-Ju , An Seong-Soo A. , Choi Jong-Rak , Chung Kwang-Hoe , Song Kyung-Soon 
Published: May 2006

AbstractWe report a novel fibrinogen variant (fibrinogen Seoul II), which has a heterozygous point mutation from CAA to CCA leading to AαGln328Pro. The mutation site is among several glutamine residues that serve as α-chain cross-linking acceptor sites. Fibrinogen Seoul II was found in a 51-year-old male patient and his family in Seoul, Korea. The patient was diagnosed with myocardial infarction at age 43. Eight years later he was admitted to the emergency room due to recurrence of the disease, where he expired under treatment with tissue plasminogen activator (t-PA). Fibrin polymerization curves, made using purified fibrinogen from the patient's relatives, showed a decreased final turbidity, suggesting Seoul II fibrin clots are composed of thinner fibers. This supposition was verified using scanning electron microscopy. Alpha-polymer formation by the mutant fibrinogen upon thrombin treatment in the presence of factor XIII and calcium was distinctly impaired. This result confirms that the residue Aα328 plays a pivotal role in α-chain cross-linking.
Genome-wide detection and analysis of homologous recombination among sequenced strains of Escherichia coli
Authors: Mau Bob , Glasner Jeremy D , Darling Aaron E , Perna Nicole T 
Published: May 2006

Abstract
Background
Comparisons of complete bacterial genomes reveal evidence of lateral transfer of DNA across otherwise clonally diverging lineages. Some lateral transfer events result in acquisition of novel genomic segments and are easily detected through genome comparison. Other more subtle lateral transfers involve homologous recombination events that result in substitution of alleles within conserved genomic regions. This type of event is observed infrequently among distantly related organisms. It is reported to be more common within species, but the frequency has been difficult to quantify since the sequences under comparison tend to have relatively few polymorphic sites.

Results
Here we report a genome-wide assessment of homologous recombination among a collection of six complete Escherichia coli and Shigella flexneri genome sequences. We construct a whole-genome multiple alignment and identify clusters of polymorphic sites that exhibit atypical patterns of nucleotide substitution using a random walk-based method. The analysis reveals one large segment (approximately 100 kb) and 186 smaller clusters of single base pair differences that suggest lateral exchange between lineages. These clusters include portions of 10% of the 3,100 genes conserved in six genomes. Statistical analysis of the functional roles of these genes reveals that several classes of genes are over-represented, including those involved in recombination, transport and motility.

Conclusion
We demonstrate that intraspecific recombination in E. coli is much more common than previously appreciated and may show a bias for certain types of genes. The described method provides high-specificity, conservative inference of past recombination events.
Melatonin modulates 900 MHz microwave-induced lipid peroxidation changes in rat brain
Authors: Köylü Halis , Mollaoglu Hakan , Ozguner Fehmi , Nazýroölu Mustafa , Delibap Namýk 
Published: May 2006

Microwaves (MW) from cellular phones may affect biological systems by increasing free radicals, which may enhance lipid peroxidation levels of the brain, thus leading to oxidative damage. Melatonin is synthesized in and secreted by the pineal gland at night and exhibits anti-oxidant properties. Several studies suggest that supplementation with anti-oxidant can influence MW-induced brain damage. The present study was designed to determine the effects of MW on the brain lipid peroxidation system, and the possible protective effects of melatonin on brain degeneration induced by MW. Twenty-eight Sprague-Dawley male rats were randomly divided into three groups as follows: (1) sham-operated control group (N-8); (2) study 900-MHz MW-exposed group (N-8); and (3) 900-MHz MW-exposed-melatonin (100 mg/kg sc before daily MW exposure treated group) (N-10). Cortex brain and hippocampus tissues were removed to study the levels of lipid peroxidation as malonyl dialdehyde. The levels of lipid peroxidation in the brain cortex and hippocampus increased in the MW group compared with the control group, although the levels in the hippocampus were decreased by MW-melatonin administration. The brain cortex lipid peroxidation levels were unaffected by melatonin treatment. We conclude that melatonin may prevent MW-induced oxidative changes in the hippocampus by strengthening the anti-oxidant defense system, by reducing oxidative stress products.
C-Terminal Amino Acid Alteration rather than Late Termination Causes Complete Deficiency of Thyroxine-Binding Globulin CD-NeuIsenburg
Authors: Moeller Lars C. , Fingerhut Anja , Lahner Harald , Grasberger Helmut , Weimer Bernd , Happ Joachim , Mann Klaus , Janssen Onno E. 
Published: May 2006

AbstractContext: T4-binding globulin (TBG) is the main transport protein for T4 in blood and a member of the superfamily of serine proteinase inhibitors. So far, 14 mutations leading to familial complete TBG deficiency have been reported. Eleven of these are caused by mutations leading to truncation of the molecule, and three are caused by single amino acid substitutions.Objective: We report and study the complete deficiency TBG variant found in a patient from NeuIsenburg, Germany (TBG-CDNI).Methods: Direct DNA sequencing was used to identify the TBG-CDNI mutation in the propositus, which was confirmed by allele-specific amplification. Site-directed mutagenesis and expression in Xenopus oocytes was used to study the secretion defect of TBG-CDNI and several variants by Western blot and T4-binding assay.Results: The deletion of two nucleotides in codon 384 (1211_1212delTC) causes a frameshift altering the last 11 residues, introduces a new glycosylation site, and elongates the molecule by seven new amino acids. In contrast to normal TBG, TBG-CDNI was not secreted by Xenopus oocytes. Elongation of normal TBG by seven alanines did not affect its secretion or binding properties. On the other hand, neither disruption of its new glycosylation site nor termination of TBG-CDNI at the normal length repaired its secretion defect.Conclusions: In this first late termination variant of complete TBG deficiency, alteration of β-strand 5B, located in the core of the molecule, rather than elongation of the molecule or introduction of a new glycosylation site, suffices to disrupt secretion of TBG-CDNI.