bluuebunny/crossref_metadata_2025_split huggingface dataset:
Inactivation of patS and hetN causes lethal levels of heterocyst differentiation in the filamentous cyanobacterium Anabaena sp. PCC 7120
Authors: Borthakur Pritty B. , Orozco Christine C. , Young‐Robbins Shirley S. , Haselkorn Robert , Callahan Sean M. 
Published: June 2005

SummaryIn the filamentous cyanobacterium Anabaena sp. PCC 7120 patS and hetN suppress the differentiation of vegetative cells into nitrogen‐fixing heterocysts to establish and maintain a pattern of single heterocysts separated by approximately 10 undifferentiated vegetative cells. Here we show that the patS‐ and hetN‐dependent suppression pathways are the only major factors that prevent vegetative cells from differentiating into heterocysts when a source of ammonia is not present. The patS and hetN pathways are independent of each other, and inactivation of both patS and hetN leads to differentiation of almost all cells of a filament in the absence of a source of fixed nitrogen, compared with approximately 9% in the wild type. Complete differentiation of filaments also occurs when nitrate is supplied as a source of fixed nitrogen, conditions that do not induce differentiation of wild‐type filaments. However, ammonia is still capable of suppressing differentiation. The percentage of cells that differentiate into heterocysts appears to be a function of time when a source of fixed nitrogen is absent or a function of growth phase when nitrate is supplied. Although differentiation proceeds unchecked in the absence of patS and hetN expression, differentiation is asynchronous and non‐random.
Post‐transcriptional control of a glucoamylase gene from Trichoderma harzianum under stress conditions
Authors: Dana María de las Mercedes , Pintor‐Toro José A. 
Published: June 2005

SummaryWe have examined the regulation of Trichoderma harzianum glucoamylase gene (Gla66) in response to different growth conditions. Transcription of the Gla66 gene is initiated from two different sites, yielding two transcripts of 2.1 kb and 2.6 kb respectively. The 2.1 kb mRNA (ST) encodes for an extracellular glucoamylase of 66 kDa. This protein shows the domains conserved in other fungal glucoamylases: a signal peptide responsible for protein secretion and a catalytic domain, both joined by a linker region. The longest transcript (LT) is untranslated, it contains an unusually extended 5′‐untranslated region and is transcribed under stress and growth limiting conditions. The translational control of LT could be defined by the presence of four upstream open reading frames (uORFs) in its 5′‐leader sequence. The analysis of these uORFs in a yeast heterologous system shows that two of these uORFs prevent the Gla66 translation under unfavourable growth conditions, when the LT transcript is accumulated.
Protein O‐mannosylation is crucial for cell wall integrity, septation and viability in fission yeast
Authors: Willer Tobias , Brandl Martin , Sipiczki Matthias , Strahl Sabine 
Published: June 2005

SummaryProtein O‐mannosyltransferases (PMTs) initiate the assembly of O‐mannosyl glycans, which are of fundamental importance in eukaryotes. The PMT family, which is classified into PMT1, PMT2 and PMT4 subfamilies, is evolutionarily conserved. Despite the fact that PMTs are crucial for viability of baker's yeast as well as of mouse, recent studies suggested that there are significant differences in the organization and properties of the O‐mannosylation machinery between yeasts and mammals. In this study we identified and characterized the PMT family of the archaeascomycete Schizosaccharomyces pombe. Unlike Saccharomyces cerevisiae where the PMT family is highly redundant, in S. pombe only one member of each PMT subfamily is present, namely, oma1+ (protein O‐mannosyltransferase), oma2+ and oma4+. They all act as protein O‐mannosyltransferases in vivo. oma1+ and oma2+ form heteromeric protein complexes and recognize different protein substrates compared to oma4+, suggesting that similar principles underlie mannosyltransfer reaction in S. pombe and budding yeast. Deletion of oma2+, as well as simultaneous deletion of oma1+ and oma4+ is lethal. Characterization of the viable S. pombe oma1Δ and oma4Δ single mutants showed that a lack of O‐mannosylation results in abnormal cell wall and septum formation, thereby severely affecting cell morphology and cell–cell separation.
Translating knowledge of genetics and pharmacology into improving everyday practice
Authors: Yatham Lakshmi N 
Published: June 2005

Bipolar disorder is associated with significant morbidity and mortality; however, many aspects of this disorder remain poorly understood. It is likely that rapid advances in molecular genetics and neuroimaging will play a major role in advancing our understanding of bipolar disorder in future.Molecular genetics studies have already identified some candidate genes; for example, the BDNF, G72 and XBP1 genes, and chromosomal ‘hot spots’, which may confer a predisposition to development of bipolar disorder. Such advances may facilitate earlier, easier and more accurate diagnosis and provide novel targets for the treatment of this condition.Brain imaging studies using positron emission tomography and single photon emission computed tomography have shown that reduction in brain 5‐hydroxytryptamine type 2 (5‐HT2) receptors may be associated with prevention of or relief from depressive symptoms. Similarly, other imaging studies suggest that increased dopamine levels in the synapse mediate the symptoms of bipolar mania and that reduction in dopamine transmission through reduction in dopamine synthesis or blockade of dopamine D2 receptors may be associated with antimanic effects. The ability of atypical antipsychotics to block both 5‐HT2 and D2 receptors and downregulate 5‐HT2 receptors may explain how these drugs treat both the depressive and manic symptoms of bipolar disorder.Although molecular genetics and imaging techniques are not yet used as clinical tools for bipolar disorder, they provide valuable data to improve the understanding of the pathophysiology of bipolar disorder and should lead to new treatments and potentially episode prevention.
Use of a new local anesthesia – intracorpus spongiosum anesthesia – in procedures on anterior urethra
Authors: YE GANG , SHAN‐HONG YI , XIANG‐WEI WANG , HUA‐QI YANG , RONG‐GUI ZHANG 
Published: June 2005

Abstract  Background:  Urologists often perform procedures on anterior urethra, which is one of the most sensitive parts in male patients. The aim of the present study was to determine the efficacy of intracorpus spongiosum anesthesia during procedures on anterior urethra in the outpatient clinic.Methods:  A dosage of 3 mL of 1% lidocaine was slowly injected into the glans penis of 51 male patients. Immediately following injection, they underwent different procedures on anterior urethra. The subjective experience of pain in the patients was assessed by questionnaire according to a pain scale.Results:  Forty‐seven patients (92.16%, 47/51) had zero pain and four cases (7.84%) had either minor or moderate discomfort, which was limited and tolerable. The anesthetic effect is immediate and has been very satisfactory. All the procedures (mean duration, 33 min), were successfully completed under the intracorpus spongiosum anesthesia. The act of injection into the glans caused instantaneous minor pain in 45 patients (88.23%, 45/51), moderate pain in four patients and no pain in two patients. There were no serious complications with this anesthetic technique, although two cases had instantaneous trance during injection of lidocaine.Conclusions:  Minor procedures on anterior urethra in an outpatient setting with intracorpus spongiosum anesthesia are generally painless, safe, simple, successful and inexpensive compared to those performed in a hospital.
Anatomical and histological studies of so‐called Müllerian duct cyst
Authors: KATO HARUAKI , HAYAMA MASAYOSHI , FURUYA SEIJI , KOBAYASHI SHINYA , ISLAM AHM MANJURUL , NISHIZAWA OSAMU 
Published: June 2005

Abstract  Background: We examined so‐called Müllerian duct cysts both histologically and immunohistochemically with anatomical observation to investigate the etiology of the ‘Müllerian duct cyst’.Methods: Five cystic lesions located in the prostatic midline were obtained from surgical specimens. A communication between the cystic lesion and the urethra via the utricular orifice was looked for and the specimens were subjected to histological and immunohistochemical testing.Results: A communication between the cyst and the urethra was confirmed in four cases, but not in one case. Histological and immunohistochemical examinations of the epithelium lining indicated that its characteristics were identical to those of the prostatic utricle in all cases.Conclusions: The so‐called Müllerian duct cyst exhibits features comparable to those previously described in the prostatic utricle. There is no evidence that these cystic lesions originate from the Müllerian duct remnant, at least in the epithelial lining. We suggest that they should be termed a prostatic utricular cyst or cystic dilation of the prostatic utricle, depending on whether an outlet to the urethra is absent or present, respectively.
Characterization, expression and function of c‐Met in canine spontaneous cancers
Authors: Liao A. T. , McMahon M. , London C. 
Published: June 2005

AbstractAberrant expression of the proto‐oncogene c‐Met has been noted in a variety of human cancers. To better define the potential role of Met dysregulation in canine cancer, the canine Met, hepatocyte growth factor (HGF) and HGF activator were cloned. Inappropriate expression of Met was present in canine tumour cell lines derived from a wide variety of cancers. Furthermore, both HGF and HGF activator were also expressed in several of these cell lines, providing evidence of a possible autocrine loop of Met activation. Stimulation of tumour cell lines with recombinant human HGF induced Met autophosphorylation, as well as activation of the downstream signalling elements Gab‐1, Akt and Erk1/2. Scattering of tumour cells and migration across a defect occurred in response to HGF stimulation. The Met inhibitor PHA665752 blocked both HGF‐induced phosphorylation of canine Met and HGF‐mediated cell cycling, scattering and migration. These studies provide evidence that Met dysregulation may play a role in the biology of canine cancer and lay the groundwork for future studies employing Met inhibitors.
Platelet, Not Endothelial, P-Selectin Is Required for Neointimal Formation After Vascular Injury
Authors: Wang Kai , Zhou Xiaorong , Zhou Zhongmin , Mal Niladri , Fan Liming , Zhang Ming , Lincoff A. Michael , Plow Edward F. , Topol Eric J. , Penn Marc S. 
Published: June 2005

Background—P-selectin blockade significantly inhibits inflammation and neointimal formation after arterial injury; however, the independent roles of platelet and endothelial P-selectins in this process are unknown. In atherosclerosis, both platelet and endothelial cell P-selectins are important. This study was designed to determine whether P-selectin expression on platelet, endothelial, or both surfaces is critical to the inflammatory response and neointimal formation after arterial injury.Methods and Results—Using wild-type (WT) and P-selectin–knockout (Psel−/−) mice, we performed bone marrow transplantation to generate chimeric mice that expressed either platelet P-selectin (Plt-Psel) or endothelial P-selectin (EC-Psel). Double injury of the carotid artery was performed in these mice as well as in WT and Psel−/−mice. Animals were euthanized 4 or 21 days after arterial injury. Morphometric data showed that there was more neointimal formation in the WT mouse group when compared with the Psel−/−mouse group (0.015±0.004 vs 0.004±0.004 mm2,P<0.001). Further comparison showed significantly less neointimal area in EC-Psel mice (0.006±0.004 mm2) compared with Plt-Psel mice (0.011±0.005 mm2,P=0.026) and WT mice (0.015±0.004 mm2,P=0.001). No significant differences were observed between WT and Plt-Psel mice or between Psel−/−and EC-Psel mice. Decreased neointimal formation was accompanied by a reduced inflammatory response, as evidenced by immunostaining of RANTES and MCP-1 4 days after injury.Conclusions—Platelet P-selectin expression, but not endothelial P-selectin, plays a crucial role in the development of neointimal formation after arterial injury, and therapeutic strategies targeting leukocyte-platelet interactions could be effective in inhibiting restenosis.
HIV-1 Rev oligomerization is not obligatory in the presence of an extra basic domain
Authors: Furnes Clemens , Arnesen Thomas , Askjaer Peter , Kjems Jørgen , Szilvay Anne Marie 
Published: June 2005

Abstract

Background
The HIV-1 Rev regulatory protein binds as an oligomeric complex to viral RNA mediating nuclear export of incompletely spliced and non-spliced viral mRNAs encoding the viral structural proteins. However, the biological significance of the obligatory complex formation of Rev upon the viral RNA is unclear.

Results
The activity of various fusion proteins based on the negative oligomerization-defect Rev mutant M4 was tested using Rev dependent reporter constructs. An artificial M4 mutant dimer and an M4 mutant containing an extra basic domain from the HTLV-I Rex protein exhibited nearly full activity when compared to wild type Rev.

Conclusion
Rev dimerization appears to be required to expose free basic domains whilst the Rev oligomeric complex remains bound to viral RNA via other basic domains.
Transport processes and large deformation during baking of bread
Authors: Zhang J. , Datta A. K. , Mukherjee S. 
Published: June 2005

AbstractA model of multiphase transport in a porous medium coupled with large deformation of the porous matrix is developed and applied to the process of bread baking. Transport‐governing equations are based on energy conservation and mass conservation of water, water vapor, and CO2 produced during baking. Deformation is caused by the pressure gradient from internal evaporation and CO2 generation. Temperature, moisture, and pressure changes in turn are affected by deformation. Bread is assumed to be viscoelastic, mechanical properties of which are functions of temperature. Geometric nonlinear effects are considered in the mechanics problem. Results are compared with those from baking experiments and literature data. Vapor pressure inside the matrix is likely to be lower than the equilibrium vapor pressure. Convective heat transfer is small compared to heat conduction and evaporation–condensation of water vapor promotes heat transfer to the inside. Rate of CO2 generation, mechanical properties of dough, and gravity together determine the final shape of the bread. © 2005 American Institute of Chemical Engineers AIChE J, 2005
A new and a reclassified ICF patient without mutations in DNMT3B and its interacting proteins SUMO‐1 and UBC9
Authors: Kloeckener‐Gruissem Barbara , Betts David R. , Zankl Andreas , Berger Wolfgang , Güngör Tayfun 
Published: June 2005

AbstractThe ICF syndrome (immunodeficiency, centromeric instability, facial anomalies) (OMIM#242860) is a rare autosomal, recessively inherited disorder. Another rare condition, ischiadic hypoplasia, renal dysgenesis, immunodeficiency, and polydactyly (IHRDIP, OMIM#243340), displays features that resemble those of the ICF syndrome. Due to the overlapping symptoms in both syndromes, we asked whether a shared underlying molecular defect exists. Two patients, each with the clinical characteristics of one of these syndromes, were subjected to conventional cytogenetic analysis and the determination of the methylation state of satellite II DNA. We found that both displayed the two hallmark features of the ICF syndrome, namely hypomethylation and centromeric instability of chromosomes 1 and 16. Therefore, we reclassified the patient previously diagnosed with the IHRDIP syndrome as an ICF patient. Since the majority of ICF patients are carriers of mutations in the methytransferase gene DNMT3B, we determined the sequence of its coding, splice site, and putative promoter region and analyzed its transcripts in both patients, without detecting any alterations. Similarly, the coding region of two DNMT3B‐interacting proteins, SUMO‐1 and UBC9, did not reveal mutations. With this study, the published number of patients that lack mutations in DNMT3B coding region increases to almost 40% of all ICF patients reported. It is, therefore, implied that a significant subset of ICF patients will have a yet unknown, alternative alteration, which may include the involvement of DNMT3B‐interacting factors or aberrations of an independent pathway. © 2005 Wiley‐Liss, Inc.
Total truncation of the molybdopterin/dimerization domains of SUOX protein in an Arab family with isolated sulfite oxidase deficiency
Authors: Seidahmed M.Z. , Alyamani E.A. , Rashed M.S. , Saadallah A.A. , Abdelbasit O.B. , Shaheed M.M. , Rasheed A. , Hamid F.A. , Sabry M.A. 
Published: June 2005

AbstractWe ascertained a patient with the full‐blown phenotype of isolated sulfite oxidase deficiency in a consanguineous Arab family. The proband's phenotype included the presence of intractable seizures in the neonatal period, some dysmorphic features, neuroradiologic findings reminiscent of hypoxic ischemic encephalopathy and rapidly progressive brain destruction leading to severe neurodevelopmental impairment. Biochemically, the patient excreted a large amount of S‐sulfocysteine with normal amounts of xanthene and hypoxanthine and had normal plasma uric acid, which was consistent with isolated sulfite oxidase deficiency. We report the identification of the first Arab mutation in SUOX, the gene for sulfite oxidase enzyme, in the ascertained family. The newly identified Arab mutation in the SUOX gene (a single nucleotide deletion, del G1244) is predicted to cause a frame shift at amino acid 117 of the translated protein with the generation of a stop codon and total truncation of the molybdo‐pterin‐ and the dimerizing‐domain(s) of SUOX protein expressed from the mutant allele. The identification of this new Arab SUOX mutation should facilitate pre‐implantation genetic diagnosis and selection of unaffected embryos for future pregnancy in the ascertained family with the mutation and related families with the same mutation. © 2005 Wiley‐Liss, Inc.
Photopolymerization and properties of UV‐curable flame‐retardant resins with hexaacrylated cyclophosphazene compared with its cured powder
Authors: Ding Jun , Liang Hongbo , Shi Wenfang , Shen Xiaofeng 
Published: June 2005

AbstractHexaacrylated cyclophosphazene (HACP) and its cured powder were blended with a commercial epoxy acrylate, EB600, to obtain UV‐curable flame‐retardant resins. The flame retardancy and the thermal stability of their cured films at elevated temperature were found to be improved from the measurements of limiting oxygen index and thermogravimetric analysis. Photopolymerization kinetics study showed that the photopolymerization rate increased with increasing amounts of HACP in EB600, whereas the unsaturation conversion decreased conversely. Dynamic mechanical thermal and mechanical properties showed that the addition of HACP had no influence, whereas adding HACP powder to EB600 had a negative effect, thus limiting its application in UV formulations. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1776–1782, 2005
Graft copolymerization of an itaconic acid/acrylamide monomer mixture onto poly(ethylene terephthalate) fibers with benzoyl peroxide
Authors: Coşkun R. , Saçak M. , Karakışla M. 
Published: June 2005

AbstractA mixture of acrylamide (AAm) and itaconic acid (IA) was grafted onto poly(ethylene terephthalate) (PET) fibers with benzoyl peroxide in aqueous media. The effects of polymerization conditions such as the temperature, polymerization time, initiator concentration, and monomer mixture ratio on grafting were investigated. The maximum graft yield was 76.1% with an AAm/IA mixture ratio of 90/10 (mol/mol). The graft yield was as low as 3% in the single grafting of IA, whereas the use of AAm as a comonomer increased the amount of IA that entered the fiber structure to 33.5%. An increase in the temperature from 65 to 85°C increased the grafting rate and saturation graft yield. However, an increase in the temperature above 85°C decreased the saturation graft yield. The graft yield increased up to an initiator concentration of 1.0 × 10−2 M and decreased afterwards. The grafting rate was 0.65th‐ and 0.74th‐order with respect to the initiator and AAm concentrations, respectively. The densities, diameters, and moisture‐regain values of the AAm/IA‐grafted PET fibers increased with the graft yield. Similarly, there was an increase in the dyeability of the AAm/IA‐grafted fibers with acidic and basic dyes. The grafted fibers were characterized with Fourier transform infrared and thermogravimetric analysis, and their morphologies were examined with scanning electron microscopy. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1795–1803, 2005
Effect of the vulcanization time and storage on the stability and physical properties of sulfur‐prevulcanized natural rubber latex
Authors: Sasidharan K. K. , Joseph Rani , Palaty Shiny , Gopalakrishnan K. S. , Rajammal G. , Pillai P. Viswanatha 
Published: June 2005

AbstractPrevulcanized natural rubber latex was prepared by the heating of the latex compound at 55°C for different periods of time (2, 4, 6, 8, and 10 h). The changes in the colloidal stability and physical properties were evaluated during the course of prevulcanization. The prevulcanized latex compounds were stored for 300 days, and the properties were monitored at different storage intervals (0, 20, 40, 60, 120, 180, 240, and 300 days). During prevulcanization, the mechanical stability time increased, and the viscosity remained almost constant. The tensile strength increased during storage for a period of 20 days. The degree of crosslinking, modulus, elongation at break, and chloroform number were varied with the time of storage. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1804–1811, 2005