bluuebunny/crossref_metadata_2025_split huggingface dataset:
Deuterium oxide promotes assembly and bundling of FtsZ protofilaments
Authors: Santra Manas Kumar , Dasgupta Debjani , Panda Dulal 
Published: October 2005

AbstractThe assembly and bundling of FtsZ protofilaments play an important role during bacterial cell division. Deuterium oxide (D2O) is known to have strong stabilization effects on the assembly dynamics of several proteins including tubulin, a homologue of FtsZ. Here, we found that D2O enhanced the light‐scattering intensity of the assembly reaction, increased sedimentable polymer mass, and induced bundling of FtsZ protofilaments. D2O also increased the stability of FtsZ polymers under challenged GTP conditions and suppressed dilution‐induced disassembly of protofilaments. D2O enhances the assembly parameters of FtsZ and microtubules albeit differently. For example, D2O induced bundling of FtsZ protofilaments, whereas it did not induce bundling of microtubules in vitro. In addition, D2O strongly suppressed the GTP hydrolysis rate of microtubules, but it had no effect on the initial rate of GTP hydrolysis of the FtsZ assembly. D2O (80%) also increased the helical content of FtsZ by 25% compared to the helical content of FtsZ in aqueous buffer. D2O was shown to reduce the binding of 4,4′‐dianilino‐1,1′‐binaphthyl‐5,5′‐disulfonic acid (bis‐ANS) to tubulin. In contrast, we found that D2O strongly enhanced the binding of bis‐ANS to FtsZ. The results indicated that D2O promotes assembly and bundling of FtsZ protofilaments by increasing hydrophobic interactions between the protofilaments. The results also suggest that the phosphate release rather than the on‐site GTP hydrolysis is the rate‐limiting step of the GTP turnover reaction. Proteins 2005. © 2005 Wiley‐Liss, Inc.
Effects of environment on the structure of Pyrococcus furiosus rubredoxin: A molecular dynamics study
Authors: Ergenekan Can E. , Tan Ming‐Liang , Ichiye Toshiko 
Published: October 2005

AbstractMolecular dynamics simulations based on a 0.95‐Å resolution crystal structure of Pyrococcus furiosus have been performed to elucidate the effects of the environment on the structure of rubredoxin, and proteins in general. Three 1‐ns simulations are reported here: two crystalline state simulations at 123 and 300 K, and a solution state simulation at 300 K. These simulations show that temperature has a greater impact on the protein structure than the close molecular contacts of the crystal matrix in rubredoxin, although both have an effect on its dynamic properties. These results indicate that differences between NMR solution structures and X‐ray crystal structures will be relatively minor if they are done at similar temperatures. In addition, the crystal simulations appears to mimic previous crystallographic experiments on the effects of cryo‐temperature on temperature factors, and might provide a useful tool in the structural analysis of protein structures solved at cryo‐temperatures. Proteins 2005. © 2005 Wiley‐Liss, Inc.
Rational genomics I: Antisense open reading frames and codon bias in short‐chain oxido reductase enzymes and the evolution of the genetic code
Authors: Duax William L. , Huether Robert , Pletnev Vladimir Z. , Langs David , Addlagatta Anthony , Connare Sonjay , Habegger Lukas , Gill Jay 
Published: October 2005

AbstractThe short‐chain oxidoreductase (SCOR) family of enzymes includes over 6000 members, extending from bacteria and archaea to humans. Nucleic acid sequence analysis reveals that significant numbers of these genes are remarkably free of stopcodons in reading frames other than the coding frame, including those on the antisense strand. The genes from this subset also use almost entirely the GC‐rich half of the 64 codons. Analysis of a million hypothetical genes having random nucleotide composition shows that the percentage of SCOR genes having multiple open reading frames exceeds random by a factor of as much as 1 × 106. Nevertheless, screening the content of the SWISS‐PROT TrEMBL database reveals that 15% of all genes contain multiple open reading frames. The SCOR genes having multiple open reading frames and a GC‐rich coding bias exhibit a similar GC bias in the nucleotide triple composition of their DNA. This bias is not correlated with the GC content of the species in which the SCOR genes are found. One possible explanation for the conservation of multiple open reading frames and extreme bias in nucleic acid composition in the family of Rossman folds is that the primordial member of this family was encoded early using only very stable GC‐rich DNA and that evolution proceeded with extremely limited introduction of any codons having two or more adenine or thymine nucleotides. These and other data suggest that the SCOR family of enzymes may even have diverged from a common ancestor before most of the AT‐rich half of the genetic code was fully defined. Proteins 2005. © 2005 Wiley‐Liss, Inc.
X‐ray absorption spectroscopic study on Ti/n‐GaN
Authors: Kumar M. Senthil , Kumar V. Suresh , Asokan K. , Chiou J. W. , Jan J. C. , Pong W. F. , Kumar J. 
Published: October 2005

AbstractFormation of low resistance and thermally stable ohmic contacts to GaN is of considerable importance for device applications. Several metallization schemes for ohmic contacts to n‐GaN with low contact resistance have been proposed and investigated by different techniques. We investigate 500 Å Ti/n‐GaN contacts of as‐deposited and rapid furnace annealed at 900 °C for 30 s, using X‐ray diffraction pattern, I–V measurements, and X‐ray absorption near edge spectra at Ti K‐ and L3,2‐edges and elucidate the mechanism responsible for the high ohmic behaviour. These measurements indicate the formation of an interfacial TixN layer and intermetallic alloys of Ti and Ga at the Ti/n‐GaN interface upon high temperature annealing. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Nonlinear longitudinal strain‐wave propagating in an elastic plate with nonequilibrium laser‐generated defects
Authors: Mirzade Fikret Kh. 
Published: October 2005

AbstractThe propagation of long nonlinear longitudinal strain waves in an isotropic elastic plate is studied in the context of a model that takes into account the joint dynamics of elastic displacements in the medium and the concentration of the nonequilibrium laser‐generated point defects (vacancies and interstitials). The input equations of the problem are reformulated in terms of only the total displacements of the medium points. In this case, the presence of lattice defects manifests itself in the emergence of a delayed response of the system to the propagation of the strain‐related perturbations, which is characteristic of media with relaxation or memory. The governing nonlinear dispersive‐dissipative equations describing the elastic displacement wave were derived with allowance made for the values of the relaxation parameter. The influence of the generation and relaxation of lattice defects on the propagation of this wave was analyzed. It is shown that, for short relaxation times of defects, the strain wave can propagate in the form of shock fronts. In the case of longer relaxation times, shock waves do not form and the strain wave propagates only in the form of solitary waves or a train of solitons. The contributions of the finiteness of the defect‐recombination rate to the linear and nonlinear elastic modulus, and lattice dissipation and dispersion parameters are found. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Structural distortions of frustrated quantum spin lattices in high magnetic fields
Authors: Derzhko Oleg , Richter Johannes , Schulenburg Jörg 
Published: October 2005

AbstractWe study the stability of some strongly frustrated antiferromagnetic spin lattices in high magnetic fields against lattice distortions. In particular, we consider a spin‐s anisotropic Heisenberg antiferromagnet on the square‐kagomé and kagomé lattices. The independent localized magnons embedded in a ferromagnetic environment, which are the ground state at the saturation field, imply lattice instabilities for appropriate lattice distortions fitting to the structure of the localized magnons. We discuss in detail the scenario of this spin‐Peierls instability in high magnetic fields which essentially depends on the values of the exchange interaction anisotropy Δ and spin s. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Influence of volatile compounds produced by yeasts predominant during processing of Coffea arabica in East Africa on growth and ochratoxin A (OTA) production by Aspergillus ochraceus
Authors: Masoud Wafa , Poll Leif , Jakobsen Mogens 
Published: October 2005

AbstractThe effects of volatile compounds produced during coffee processing by Pichia anomala, P. kluyveri and Hanseniaspora uvarum on growth of Aspergillus ochraceus and production of ochratoxin A (OTA) were studied. On malt extract agar (MEA) and on coffee agar (CA), exposure of A. ochraceus to the gaseous phase of malt yeast glucose peptone (MYGP) plates inoculated with P. anomala, P. kluyveri and H. uvarum inhibited fungal growth, with the two Pichia spp. showing the strongest effect. The main esters and alcohols produced by the three yeasts were ethyl acetate, isobutyl acetate, 2‐phenyl ethyl acetate, ethyl propionate and isoamyl alcohol. The individual esters and alcohols were found to affect fungal growth. The most effective compound in inhibiting fungal growth was 2‐phenyl ethyl acetate; which at 48 µg/l headspace completely inhibited growth of A. ochraceus. Exposure of A. ochraceus to the gaseous phase of MYGP plates inoculated with P. anomala, P. kluyveri and H. uvarum prevented production of OTA. On CA medium, only the headspace of P. anomala and P. kluyveri prevented OTA production. Furthermore, when A. ochraceus was exposed to the headspace of the individual volatile compounds, 2‐phenyl ethyl acetate was the most effective in preventing OTA production. Prevention of OTA seems to be due to reduction of fungal biomass. Copyright © 2005 John Wiley & Sons, Ltd.
The impact of climate change on the adaptation of marine fish in the Baltic Sea
Authors: Ojaveer Evald , Kalejs Margers 
Published: October 2005

AbstractThe biota in the Baltic Sea has formed under wide variations in environmental conditions induced by climate change since the last glaciation. Areas of the Baltic Sea display marked differences in salinity, oxygen content and temperature of water layers, timing of the peak production cycle, and other basic environmental conditions. Some of the most important adaptations of marine fish to the conditions in the Baltic Sea facilitate reproduction at low and changeable salinity and oxygen deficiency in deeper layers, and enhance the survival of their offspring in early stages of development. In sea herring, flounder, cod, and other late immigrants (which probably colonized the Baltic after the Ancylus stage), abundant year classes occur in periods of higher salinity. During periods of low salinity, the abundance and spatial distribution of marine species is reduced. Probable earlier immigrants (e.g. gulf herring) are less dependent on saltwater inflows, but they depend more on local processes. The success of marine species in different areas of the Baltic Sea has been variable, and species adaptation, mediated by climate oscillations, has resulted in the formation of local populations.
Placental growth factor in the cerebrospinal fluid of women with preeclampsia
Authors: Foyouzi N. , Norwitz E.R. , Tsen L.C. , Buhimschi C.S. , Buhimschi I.A. 
Published: October 2005

AbstractObjective: Recent data suggest that excess circulating soluble fms‐like tyrosine kinase‐1 (sFlt‐1) may causally relate to preeclampsia. This study investigates the levels of sFlt‐1, VEGF, and PlGF in cerebrospinal fluid (CSF) of patients with preeclampsia and normotensive controls. Methods: CSF was collected from preeclamptic patients (n = 15) and controls (n = 7) at the time of spinal anesthesia and assayed for PlGF, sFlt‐1, and VEGF (total and free) by specific immunoassays. Results: All sought angiogenic factors were measurable. Levels of free PlGF but not sFlt‐1 or VEGF (total or free) were increased in CSF of preeclamptic women. There was no significant difference in the ratios of angiogenic factors in the CSF of women with preeclampsia. There was no correlation between levels of angiogenic factors and CSF cell counts or severity of symptoms. Conclusion: Elevated levels of PlGF in CSF preeclamptic women may promote vascular permeability and contribute to the hypertensive encephalopathy seen in such patients.
MUSICAL INSTRUMENT MAKING IN GEORGIAN LONDON, 1753–1809: EVIDENCE FROM THE PROCEEDINGS OF THE OLD BAILEY AND THE MIDDLESEX SESSIONS OF THE PEACE
Authors: NEX JENNY , WHITEHEAD LANCE 
Published: October 2005

Throughout the Georgian period London was the most significant British centre for musical instrument manufacture. Traditionally, research in this area has focused on the surviving instruments themselves, thereby emphasizing those makers in charge of flourishing workshops and those who were in the habit of signing their products. By examining archival sources, however, it is possible to glean a more complete picture of musical instrument production, through the identification of ‘hidden’ makers unrepresented by extant instruments, the establishment of patterns of settlement and the highlighting of relationships between different builders.Two principal sources form the basis of this study: the online edition of the Proceedings of the Old Bailey and the Middlesex Sessions of the Peace Records. While these sources are an important record of crime and punishment, it is the unwitting testimony of the trials rather than the crimes, the legal procedures or the punishments that is the primary focus of this study. Indeed, since the trials enable the identification of people involved at all levels of the musical instrument trade, it is arguable that they provide one of the most significant means of establishing some of the processes characterizing the industry during the second half of the eighteenth century.
Systematic review: acute colonic pseudo‐obstruction
Authors: SAUNDERS M. D. , KIMMEY M. B. 
Published: October 2005

SummaryAcute colonic pseudo‐obstruction is the clinical syndrome of acute large bowel dilatation without mechanical obstruction that is an important cause of morbidity and mortality. Acute colonic pseudo‐obstruction occurs in hospitalized or institutionalized patients with serious underlying medical and surgical conditions.The pathogenesis of acute colonic pseudo‐obstruction is not completely understood but likely results from an imbalance in the autonomic regulation of colonic motor function. Metabolic or pharmacological factors, as well as spinal or retroperitoneal trauma, may alter the autonomic regulation of colonic function, leading to excessive parasympathetic suppression or sympathetic stimulation. This imbalance results in colonic atony and dilatation.Early recognition and appropriate management are critical to minimizing morbidity and mortality. The mortality rate is estimated at 40% when ischaemia or perforation occurs. The best‐studied treatment of acute colonic pseudo‐obstruction is intravenous neostigmine, which leads to prompt colon decompression in the majority of patients after a single infusion. In patients failing or having contraindications to neostigmine, colonoscopic decompression is the active intervention of choice. Surgery is reserved for those with peritonitis or perforation.
Low rectal volumes in patients suffering from fecal incontinence: what does it mean?
Authors: SIPROUDHIS L. , EL ABKARI M. , EL ALAOUI M. , JUGUET F. , BRETAGNE J. F. 
Published: October 2005

SummaryBackground : Rectal perception and adaptation to distension are widely heterogeneous in subjects with faecal incontinence.Aim : To quantify rectal physiology in patients with incontinence and low maximum rectal volume, according to AGA guidelines on anorectal testing techniques.Patients and methods : 148 patients (12 men, 136 female) with incontinence to liquid and/or solid stools were investigated. Distending isobaric procedures were carried out using an electronic barostat in order to analyse perception and adaptation of the rectum.Results : Pain during isovolumic rectal distension at a level of 100 mL or less was experienced in 21 subjects (14.2%). As defined by isobaric distensions, incontinent patients with low MTV had more frequently a hypocompliant rectum (62%) when compared with those with higher MTV (31%, P = 0.046). Perception scores tended to be higher at each step of distending rectal pressure: incontinent patients with low MTV had more frequently a hypersensitive rectum (48%) when compared with those with normal or high MTV (24%, P = 0.035). Only four of 21 incontinent subjects with low MTV had an isolated hypersensitive rectum.Conclusion : Both sensitivity and compliance are altered in patients with low MTV. A more extensive study of the role of sensory and compliance aspects of subjects with incontinence is warranted.
Poor metabolizer genotype status of CYP2C19 is a risk factor for developing gastric cancer in Japanese patients with Helicobacter pylori infection
Authors: SUGIMOTO M. , FURUTA T. , SHIRAI N. , NAKAMURA A. , KAJIMURA M. , SUGIMURA H. , HISHIDA A. , ISHIZAKI T. 
Published: October 2005

SummaryBackground : Cytochrome P450 2C19 (CYP2C19) polymorphism has been associated with the development of lung, liver or oesophageal cancer by detoxification of carcinogen(s) or activation of procarcinogen(s).Aim:  To clarify the association between CYP2C19 polymorphisms and gastric cancer development in Japanese.Methods : We determined CYP2C19 genotypes (CYP2C19*1, *2 and *3) in 111 Helicobacter pylori‐positive patients with gastric cancer and 315 H. pylori‐positive controls without gastric cancer consisting of patients with gastritis only or peptic ulcer. Frequencies of CYP2C19 genotypes and serum pepsinogen I and II levels, a biomarker of gastric atrophy, in the gastric cancers and controls were compared.Results : Frequencies of homozygous extensive metabolizers, heterozygous extensive metabolizers and poor metabolizers were 31.5%, 42.3% and 26.2% in the gastric cancers and 38.1%, 47.0% and 14.9% in the controls, respectively (P = 0.046). Poor metabolizers were associated with an increased risk for developing gastric cancer with the age‐ and sex‐adjusted odds ratio (OR) of 1.975 [95% confidence interval (CI): 1.068–3.649], especially for diffuse type (OR: 3.385, CI: 1.187–9.648). There is no significant association between CYP2C19 genotypes and serum pepsinogen I level or pepsinogen I/II ratios, although serum pepsinogen I level in gastric cancers were significantly decreased.Conclusions : In H. pylori‐positive Japanese, poor metabolizers of CYP2C19 appear to be at an increased risk for developing gastric cancer, especially diffuse type, and may require an intensive follow‐up for scrutinizing possible gastric cancer development.
Efficacy of depot long‐acting release octreotide therapy in severe dumping syndrome
Authors: PENNING C. , VECHT J. , MASCLEE A. A. M. 
Published: October 2005

SummaryBackground:  Dumping syndrome is a serious complication occurring in 10% of patients after gastric surgery. Dumping symptoms are effectively reduced by subcutaneous application of the somatostatin analogue octreotide, but side‐effects limit its use.Aim:  To evaluate the efficacy of depot long‐acting release octreotide (Sandostatin‐LAR) vs. octreotide subcutaneous on dumping symptoms, quality of life and side‐effects.Methods:  Twelve patients (five females, age 58 ± 3 years) with severe dumping symptoms, requiring daily use of octreotide subcutaneous, were included in an open study and changed from octreotide subcutaneous after a 2 weeks washout to Sandostatin‐LAR 10 mg i.m., every 4 weeks for 6 months. Symptoms (diary), body weight, fat excretion, food intake and Gastrointestinal Specific Quality of Life Index were evaluated.Results:  Gastrointestinal Specific Quality of Life Index increased significantly (P < 0.05) during Sandostatin‐LAR treatment (88 ± 4) compared with octreotide (74 ± 4) and washout (75 ± 6). During Sandostatin‐LAR treatment, abdominal symptom score was lower compared with octreotide and washout, but not significantly. During Sandostatin‐LAR treatment, body weight increased (66 ± 4 to 70 ± 3 kg; P = 0.19).Conclusions:  Sandostatin‐LAR is at least as effective as octreotide subcutaneous in suppressing symptoms in patients with severe dumping syndrome and is more effective than octreotide subcutaneous in increasing body weight and quality of life.
Review article: the treatment of non‐alcoholic steatohepatitis with thiazolidinediones
Authors: REYNAERT H. , GEERTS A. , HENRION J. 
Published: October 2005

SummaryIt is generally accepted that non‐alcoholic fatty liver disease will be the most frequent liver disease in the near future and that the management of patients with non‐alcoholic fatty liver disease will be a challenge for hepatologists in the next decades.Non‐alcoholic fatty liver disease is considered the hepatic manifestation of the metabolic syndrome, in which insulin resistance plays a crucial role. Although steatosis will often not progress to severe liver disease, in some patients, it results in cirrhosis and even hepatocellular carcinoma. Therefore, it is important to identify those patients at risk for developing fibrosis. Age, diabetes, obesity and hypertriglyceridaemia are independent risk factors for fibrosis in patients with elevated serum alanine aminotransferase levels and steatosis on ultrasound. The presence of multiple metabolic disorders increases the risk.Apart from diet, exercise and correction of underlying metabolic abnormalities, no specific treatment is available at the moment. Theoretically, thiazolidinediones are an attractive way to treat non‐alcoholic fatty liver disease, because they improve insulin resistance. Some preliminary studies with thiazolidinediones were encouraging, as steatosis, inflammation and fibrosis improved in a substantial number of patients. Although no serious side effects occurred in the pilot studies, we should look vigilantly for hepatotoxicity, as the first generation thiazolidinediones proved to be toxic for the liver.
The expression of minichromosome maintenance protein‐2 in normal and abnormal megakaryocytes and comparison with the proliferative marker Ki‐67
Authors: Lampert Irvin A. , Horncastle Donna , Dilworth Steven , Roberts Irene , Alison Malcolm R. , Naresh Kikkeri N. 
Published: October 2005

SummaryThe minichromosome maintenance (Mcm) and Cdc6 proteins are important regulators of eucaryotic DNA replication. In most normal tissues, a similar proportion of cells express Mcm‐2 and Ki‐67. The present study showed that in both normal and abnormal states, the proportion of megakaryocytes expressing Mcm‐2 is roughly seven times as many as those that express Ki‐67. This is likely to be related to the process of endomitosis and endoreduplication. We also demonstrated that a significantly lower proportion of megakaryocytes in myelodysplastic syndrome express Mcm‐2. These findings provide new insights into megakaryocyte biology.