bluuebunny/crossref_metadata_2025_split huggingface dataset:
Carcinoma ex pleomorphic adenoma: Diagnostic difficulty and outcome
Authors: Zbären Peter , Zbären Sibylle , Caversaccio Marco D. , Stauffer Edouard 
Published: June 2008

ObjectiveTo analyze a series of carcinoma ex pleomorphic adenoma (CXPA) and to assess the diagnostic difficulties.Study DesignThe clinical presentation of 24 CXPAs was compared with 300 pleomorphic adenomas (PAs). Furthermore, pathohistological findings and follow‐up results of CXPAs were evaluated.ResultsEight of 24 (33%) CXPAs versus 41 of 300 (14%) PAs were localized in the deep lobe (P < 0.05). Forty‐two percent of CXPAs versus 6 percent of PAs, respectively, were greater than 4 cm (P < 0.05). The sensitivity in detecting CXPA by fine‐needle aspiration cytology (FNAC) was 47 percent. The tumor was known to be malignant preoperatively in 10 (42%) patients. Six of 24 (25%) patients with CXPA developed a tumor recurrence. The overall 5‐year survival rate of CXPA was 76 percent.ConclusionCXPAs are difficult to identify preoperatively. FNAC has a low accuracy and sensitivity. CXPAs versus PAs are significantly more frequently localized in the deep lobe and are significantly greater in size.
Increased risk of otitis media with effusion in allergic children presenting with adenoiditis
Authors: Marseglia Gian Luigi , Pagella Fabio , Caimmi Davide , Caimmi Silvia , Castellazzi Anna Maria , Poddighe Dimitri , Klersy Catherine , Ciprandi Giorgio 
Published: June 2008

ObjectiveOtitis media with effusion (OME) is a common disorder in childhood. The aim of the study was to assess the association of atopy and endoscopic features with the presence of OME.Subjects and MethodsThis cross‐sectional study evaluated 287 children presenting with acute upper‐airway infections persistent for at least ten days and tested through nasal endoscopy and skin‐prick test.ResultsFifty‐three patients had a diagnosis of OME; out of them, 23 showed acute rhinosinusitis, ten adenoiditis, and 20 both features. OME was diagnosed in 26 atopic children and in 27 nonatopic ones. On a multivariable analysis, allergic rhinitis, endoscopic pattern of adenoiditis, and younger age were all shown to be independently associated with a diagnosis of OME.ConclusionsThis study suggests that allergic rhinitis and adenoiditis are significant risk factors to OME development and that the risk becomes higher when these two conditions are con‐comitantly present.
Treatment outcomes for nontuberculous mycobacterial cervicofacial lymphadenitis in children based on the type of surgical intervention
Authors: Wei Julie L. , Bond Justin , Sykes Kevin J. , Selvarangan Rangaraj , Jackson Mary Anne 
Published: June 2008

ObjectiveTo report treatment outcomes of nontuberculous mycobacteria (NTM) cervicofacial lymphadenitis.Study DesignA retrospective study from 1995 to 2006.Subjects and MethodsFifty‐one patients (mean age, 30.3 months).ResultsAll but one patient presented with lymphadenopathy. The mean time from symptoms to diagnosis was 42.3 days. Tuberculin skin testing (TST) was performed on 21 of 51 patients and was positive on 14 of 21 patients. Imaging was ordered in 23; 19 had CT scans. Pathology confirmed caseating granuloma in 45 (88%); cultures grew Mycobacterium avium‐intracellulare complex in 46 of 51. Interventions included fine‐needle aspiration (5, 10%), incision and drainage ± curettage (24, 46%), and complete excisional biopsy (20, 38%). Of those who underwent complete excisional biopsy initially, 95 percent were cured compared with 32 of 51 (63%) with nonexcisional surgery. Macrolides and rifampin were more likely to be recommended in referred cases and when nonexcisional surgical treatment was not feasible or had failed. The average total duration of antibiotic therapy was 89.1 days.ConclusionNTM infections require high levels of suspicion for timely diagnosis, and complete excisional biopsy results in least likelihood of persistent/recurrent disease.
Biofilms with fungi in chronic rhinosinusitis
Authors: Healy David Y. , Leid Jeff G. , Sanderson Alicia R. , Hunsaker Darrell H. 
Published: June 2008

ObjectivesDemonstrate that bacterial biofilm in sinus mucosal samples from patients with eosinophilic mucin chronic rhinosinusitis (EMCRS) and allergic fungal rhinosinusitis (AFRS) contains fungal elements; identify specific organisms in the biofilm.MethodsMucosa samples from 11 patients undergoing sinus surgery were collected. Patients were classified as having AFRS, EMCRS, or chronic rhinosinusitis (CRS) based on histopathologic findings. Three mucosal samples from controls were also collected. Samples were stained with specific bacterial fluorescent in situ hybridization (FISH) DNA probes (Haemophilus influenzae, Streptococcus pneumophilia, Staphylococcus aureus, and Pseudomonas aeruginosa) and a general pan‐fungal FISH probe. The samples were analyzed for bacterial biofilm ultrastructure and fungal elements using epifluorescent microscopy.ResultsBacterial biofilm was demonstrated in 9/11 samples and 2/3 controls. H. influenzae was the predominant biofilm present. There was a trend showing more fungal elements in AFRS and EMCRS biofilms than in CRS and controls.ConclusionThis is a preliminary study demonstrating fungal elements within sinus mucosal biofilm and demonstrating biofilm in AFRS.
Late Cretaceous (Campanian—Maastrichtian) marine reptiles from the Adaffa Formation, NW Saudi Arabia
Authors: KEAR B. P. , RICH T. H. , ALI M. A. , AL-MUFARRIH Y. A. , MATIRI A. H. , MASARY A. M. , ATTIA Y. 
Published: June 2008

AbstractMarine reptile remains occur in the Upper Cretaceous (lower Campanian to lower Maastrichtian) Adaffa Formation of NW Saudi Arabia. This is the first detailed report of late Mesozoic marine reptiles from the Arabian Peninsula. The fossils include bothremydid (cf. Taphrosphyini) turtles, dyrosaurid crocodyliforms, elasmosaurid plesiosaurs, mosasaurs (Prognathodon, plioplatecarpines) and an indeterminate small varanoid. The assemblage is compositionally similar to contemporary faunas from elsewhere in the Middle East/North Africa, and comprises taxa that are typical of the southern margin of the Mediterranean Tethys.
Approximate amenability of Fréchet algebras
Authors: LAWSON P. , READ C. J. 
Published: June 2008

AbstractThe notion of approximate amenability was introduced by Ghahramani and Loy, in the hope that it would yield Banach algebras without bounded approximate identity which nonetheless had a form of amenability. So far, however, all known approximately amenable Banach algebras have bounded approximate identities (b.a.i.). In this paper we define approximate amenability and contractibility of Fréchet algebras, and we prove the analogue of the result for Banach algebras that these properties are equivalent. We give examples of Fréchet algebras which are approximately contractible, but which do not have a bounded approximate identity. For a good many Fréchet algebras without b.a.i., we find either that the algebra is approximately amenable, or it is “obviously” not approximately amenable because it has continuous point derivations. So the situation for Fréchet algebras is quite close to what was hoped for Banach algebras.
The effect of twisting on the 2-Selmer group
Authors: SWINNERTON–DYER PETER 
Published: June 2008

AbstractLet Γ be an elliptic curve defined over Q, all of whose 2-division points are rational, and let Γb be its quadratic twist by b. Subject to a mild additional condition on Γ, we find the limit of the probability distribution of the dimension of the 2-Selmer group of Γb as the number of prime factors of b increases; and we show that this distribution depends only on whether the 2-Selmer group of Γ has odd or even dimension.
Gaussian integer points of analytic functions in a half-plane
Authors: FLETCHER ALASTAIR 
Published: June 2008

AbstractA classical result of Pólya states that 2zis the slowest growing transcendental entire function taking integer values on the non-negative integers. Langley generalised this result to show that 2zis the slowest growing transcendental function in the closed right half-plane Ω = {z∈: Re(z) ≥ 0} taking integer values on the non-negative integers. LetEbe a subset of the Gaussian integers in the open right half-plane with positive lower density and letfbe an analytic function in Ω taking values in the Gaussian integers onE. Then in this paper we prove that iffdoes not grow too rapidly, thenfmust be a polynomial. More precisely, there existsL> 0 such that if either the order of growth offis less than 2 or the order of growth is 2 and the type is less thanL, thenfis a polynomial.
Web 2.0 and the ever elusive balance between information explosion and data mining
Authors: Krishna Abhay 
Published: June 2008

AbstractIn a fascinating tussle of perspectives in Volume 6 and issue no 3 of april 2008 Frontiers in Ecology and Evolution, Martin A Nuñez and Gregory M Crustinger enlist ways to brace up with the recent literature. They advocate that PhD students should choose a well studied system to have better chances of success. On the other side of this fascinating tussle Daniel Simberloff and Nathan J Sanders agree with there enthusiastic case and approaches for bracing up with the recent literature. However, they disagree with the play safe strategy of start-ups in ecology and evolution.For me this tussle of perspectives is really fascinating. It underlines the story of our times. In the times of information explosion, should we concentrate on mining this information for knowledge or should we keep adding to this information explosion. This dilemma fits well in the context of the tussle by a quote from Nassim Nicholas Taleb “ It is almost impossible these days to finish PhD without excessive intellectual curiosity and it is impossible to get a faculty position without narrowly specializing in a chosen field ”.Here in this letter, I want to harmonize the two perspectives by arguing that coexistence of information explosion and data mining is possible. We should strive for that ever elusive balance and I discuss below how Web 2.0 will enable it. Web 2.0, still in its infancy already shows promising results and I discuss below these usages.
Biosynthesis of fluorescent allophycocyanin α‐subunits by autocatalysis in Escherichia coli
Authors: Zhang Weijie , Guan Xiangyu , Yang Yu , Ge Baosheng , Chen Huaxin , Li Fuchao , Qin Song 
Published: June 2008

APC (allophycocyanin) is widely used for fluorescence tagging and may be a promising antioxidant agent for use within the food and pharmaceutical industries. Chromophore attachment to apo‐ApcA (apo‐APC α‐subunit without chromophore) can be autocatalysed both in vitro and in vivo. In the present study, a plasmid containing genes of apo‐ApcA and chromophore synthetases [HO1 (ferredoxin‐dependent haem oxygenase) and PcyA (phycocyanobilin:ferredoxin oxidoreductase)] was constructed and expressed in Escherichia coli. The results show that holo‐ApcA (APC α‐subunit with chromophore) can be synthesized by autocatalysis in E. coli. Recombinant holo‐ApcA showed the same spectral and fluorescent properties as PC (phycocyanin) and could serve as a good substitute for native PC for fluorescent tagging. Moreover, recombinant ApcA can inhibit hydroxyl and peroxyl radicals more strongly than holo‐ApcA and native APC. The EC50 values were 296.4±22.4 μg/ml against hydroxyl radicals and 38.5±2.6 μg/ml against peroxyl radicals.
The 5′–3′ exoribonuclease pacman is required for epithelial sheet sealing in Drosophila and genetically interacts with the phosphatase puckered
Authors: Grima Dominic P. , Sullivan Melanie , Zabolotskaya Maria V. , Browne Cathy , Seago Julian , Wan Kay Chong , Okada Yoshio , Newbury Sarah F. 
Published: June 2008

Background information. Ribonucleases have been well studied in yeast and bacteria, but their biological significance to developmental processes in multicellular organisms is not well understood. However, there is increasing evidence that specific timed transcript degradation is critical for regulation of many cellular processes, including translational repression, nonsense‐mediated decay and RNA interference. The Drosophila gene pacman is highly homologous to the major yeast exoribonuclease XRN1 and is the only known cytoplasmic 5′–3′ exoribonuclease in eukaryotes. To determine the effects of this exoribonuclease in development we have constructed a number of mutations in pacman by P‐element excision and characterized the resulting phenotypes.Results. Mutations in pacman resulted in flies with a number of specific phenotypes, such as low viability, dull wings, crooked legs, failure of correct dorsal/thorax closure and defects in wound healing. The epithelial sheet movement involved in dorsal/thorax closure is a conserved morphogenetic process which is similar to that of hind‐brain closure in vertebrates and wound healing in humans. As the JNK (c‐Jun N‐terminal kinase) signalling pathway is known to be involved in dorsal/thorax closure and wound healing, we tested whether pacman affects JNK signalling. Our experiments demonstrate that pacman genetically interacts with puckered, a phosphatase that negatively regulates the JNK signalling pathway.Conclusions. These results reveal that the 5′–3′ exoribonuclease pacman is required for a critical aspect of epithelial sheet sealing in Drosophila. Since these mutations result in specific phenotypes, our data suggest that the exoribonuclease Pacman targets a specific subset of mRNAs involved in this process. One of these targets could be a member of the JNK signalling pathway, although it is possible that a parallel pathway may instead be affected. The exoribonuclease pacman is highly conserved in all eukaryotes, therefore it is likely that it is involved in similar morphological processes, such as wound healing in human cells.
Caffeine induces Ca2+ release by reducing the threshold for luminal Ca2+ activation of the ryanodine receptor
Authors: Kong Huihui , Jones Peter P. , Koop Andrea , Zhang Lin , Duff Henry J. , Chen S. R. Wayne 
Published: June 2008

Caffeine has long been used as a pharmacological probe for studying RyR (ryanodine receptor)-mediated Ca2+ release and cardiac arrhythmias. However, the precise mechanism by which caffeine activates RyRs is elusive. In the present study, we investigated the effects of caffeine on spontaneous Ca2+ release and on the response of single RyR2 (cardiac RyR) channels to luminal or cytosolic Ca2+. We found that HEK-293 cells (human embryonic kidney cells) expressing RyR2 displayed partial or ‘quantal’ Ca2+ release in response to repetitive additions of submaximal concentrations of caffeine. This quantal Ca2+ release was abolished by ryanodine. Monitoring of endoplasmic reticulum luminal Ca2+ revealed that caffeine reduced the luminal Ca2+ threshold at which spontaneous Ca2+ release occurs. Interestingly, spontaneous Ca2+ release in the form of Ca2+ oscillations persisted in the presence of 10 mM caffeine, and was diminished by ryanodine, demonstrating that unlike ryanodine, caffeine, even at high concentrations, does not hold the channel open. At the single-channel level, caffeine markedly reduced the threshold for luminal Ca2+ activation, but had little effect on the threshold for cytosolic Ca2+ activation, indicating that the major action of caffeine is to reduce the luminal, but not the cytosolic, Ca2+ activation threshold. Furthermore, as with caffeine, the clinically relevant, pro-arrhythmic methylxanthines aminophylline and theophylline potentiated luminal Ca2+ activation of RyR2, and increased the propensity for spontaneous Ca2+ release, mimicking the effects of disease-linked RyR2 mutations. Collectively, our results demonstrate that caffeine triggers Ca2+ release by reducing the threshold for luminal Ca2+ activation of RyR2, and suggest that disease-linked RyR2 mutations and RyR2-interacting pro-arrhythmic agents may share the same arrhythmogenic mechanism.
Localization and characterization of the novel protein encoded by C20orf3
Authors: Ilhan Aysegul , Gartner Wolfgang , Nabokikh Anastasiya , Daneva Teodora , Majdic Otto , Cohen Gerald , Böhmig Georg A. , Base Wolfgang , Hörl Walter H. , Wagner Ludwig 
Published: June 2008

In the present study, we characterized the gene product of open reading frame 3 encoded at human chromosome 20 (C20orf3), which represents a member of the lactonohydrolase super family. Multiple-tissue Northern blot analysis showed ubiquitous expression of the 2.4 kb transcript coding for 416 amino acids, with highest levels in human liver, placenta and kidney. After recombinant production of protein variants in Escherichia coli and insect cells, antibodies directed against different epitopes within the C20orf3 gene product were generated. Using these immunoreagents, protein expression was demonstrated in the liver, and glomerular and tubular structures of the kidney, as well as in endothelial cells and arterial wall. Positive staining was also observed at the pancreatic islets of Langerhans. Using immunoblotting, we identified three size variants. In line with the results of in silico analysis demonstrating a single transmembrane sequence (amino acids 40–61) at the N-terminus of the full-length protein, FACS cell-surface staining confirmed a mainly extracellular localization of the full-length protein. Sucrose density gradient cell fractionation revealed membrane association of the dominant 50 kDa variant in HepG2 and Rin-5F cells. The finding of a strong arylesterase activity with β-naphthyl acetate and phenyl acetate of the C20orf3 protein-containing fractions suggests potential involvement of this protein in enzymatic processes. C20orf3 promoter-driven reporter assays, which were verified by gene-specific RT-qPCR (real-time quantitative PCR) showed a strong inhibitory effect of human serum on transcription using the HEK-293 human embryonic kidney cell line. In conclusion, we characterized the structure and expression pattern of the C20orf3 gene product. According to a series of analogies with PON (paraoxonase) family members, we speculate that the C20orf3 gene product represents a new member of this important protein family present at the cellular level.
Assembly of a membrane receptor complex: roles of the uroplakin II prosequence in regulating uroplakin bacterial receptor oligomerization
Authors: Hu Chih-Chi Andrew , Bachmann Thomas , Zhou Ge , Liang Feng-Xia , Ghiso Jorge , Kreibich Gert , Sun Tung-Tien 
Published: June 2008

The apical surface of the mammalian urothelium is almost completely covered by two-dimensional protein crystals (known as urothelial plaques) of hexagonally packed 16 nm particles consisting of two UP (uroplakin) heterodimers, i.e. UPs Ia/II and Ib/III pairs. UPs are functionally important as they contribute to the urothelial permeability barrier function, and UPIa may serve as the receptor for the uropathogenic Escherichia coli that causes over 90% of urinary tract infections. We study here how the UP proteins are assembled and targeted to the urothelial apical surface, paying special attention to the roles of the prosequence of UPII in UP oligomerization. We show that (i) the formation of the UPIa/UPII heterodimer, necessary for ER (endoplasmic reticulum) exit, requires disulfide formation in the prosequence domain of proUPII (the immature form of UPII still containing its prosequence); (ii) differentiation-dependent N-glycosylation of the prosequence leads to UP stabilization; (iii) a failure to form tetramers in cultured urothelial cells, in part due to altered glycosylation of the prosequence, may block two-dimensional crystal formation; and (iv) the prosequence of UPII remains attached to the mature protein complex on the urothelial apical surface even after it has been cleaved by the trans-Golgi-network-associated furin. Our results indicate that proper secondary modifications of the prosequence of UPII play important roles in regulating the oligomerization and function of the UP protein complex.
Structural and mechanistic insights into type II trypanosomatid tryparedoxin-dependent peroxidases
Authors: Alphey Magnus S. , König Janine , Fairlamb Alan H. 
Published: June 2008

TbTDPX (Trypanosoma brucei tryparedoxin-dependent peroxidase) is a genetically validated drug target in the fight against African sleeping sickness. Despite its similarity to members of the GPX (glutathione peroxidase) family, TbTDPX2 is functional as a monomer, lacks a selenocysteine residue and relies instead on peroxidatic and resolving cysteine residues for catalysis and uses tryparedoxin rather than glutathione as electron donor. Kinetic studies indicate a saturable Ping Pong mechanism, unlike selenium-dependent GPXs, which display infinite Km and Vmax values. The structure of the reduced enzyme at 2.1 Å (0.21 nm) resolution reveals that the catalytic thiol groups are widely separated [19 Å (0.19 nm)] and thus unable to form a disulphide bond without a large conformational change in the secondary-structure architecture, as reported for certain plant GPXs. A model of the oxidized enzyme structure is presented and the implications for small-molecule inhibition are discussed.
Characterization of the topology and functional domains of RKTG
Authors: Luo Xiaolin , Feng Lin , Jiang Xiaomeng , Xiao Fei , Wang Zhenzhen , Feng Gen-Sheng , Chen Yan 
Published: June 2008

RKTG (Raf kinase trapping to Golgi) is exclusively localized at the Golgi apparatus and functions as a spatial regulator of Raf-1 kinase by sequestrating Raf-1 to the Golgi. Based on the structural similarity with adiponectin receptors, RKTG was predicted to be a seven-transmembrane protein with a cytosolic N-terminus, distinct from classical GPCRs (G-protein-coupled receptors). We analysed in detail the topology and functional domains of RKTG in this study. We determined that the N-terminus of RKTG is localized on the cytosolic side. Two short stretches of amino acid sequences at the membrane proximal to the N- and C-termini (amino acids 61–71 and 299–303 respectively) were indispensable for Golgi localization of RKTG, but were not required for the interaction with Raf-1. The three loops facing the cytosol between the transmembrane domains had different roles in Golgi localization and Raf-1 interaction. While the first cytosolic loop was only important for Golgi localization, the third cytosolic loop was necessary for both Golgi localization and Raf-1 sequestration. Taken together, these findings suggest that RKTG is a type III membrane protein with its N-terminus facing the cytosol and multiple sequences are responsible for its localization at the Golgi apparatus and Raf-1 interaction. As RKTG is the first discovered Golgi protein with seven transmembrane domains, the knowledge derived from this study would not only provide structural information about the protein, but also pave the way for future characterization of the unique functions of RKTG in the regulation of cell signalling.
The pancreatic β-cell: birth, life and death
Authors: Rutter Guy A. , Wong F. Susan 
Published: June 2008

Defective insulin secretion is a hallmark of all forms of diabetes. Whereas Type 1 diabetes has long been known to result from the immune-mediated destruction of β-cells, Type 2 diabetes appears to involve both loss of β-cell mass and glucose sensitivity in the face of extrapancreatic insulin resistance. We summarize here the proceedings of a Biochemical Society Focused Meeting, held at the St Thomas campus of King's College London in December 2007, which highlighted recent research advances targeting the β-cell.