bluuebunny/crossref_metadata_2025 huggingface dataset:
EVIDENCE FOR LATERAL TRANSFER OF AN IE INTRON BETWEEN FUNGAL AND RED ALGAL SMALL SUBUNIT RRNA GENES1
Authors: Müller Kirsten M. , Ellenor Darlene W. , Sherwood Alison R. , Sheath Robert G. , Cannone Jamie J. , Gutell Robin R.
Published: March 2005

A previous study of the North American biogeography of the red algal genus Hildenbrandia noted the presence of group I introns in the nuclear small subunit (SSU) rRNA gene of the marine species H. rubra (Sommerf.) Menegh. Group IC1 introns have been previously reported at positions 516 and 1506 in the nuclear SSU RNA genes in the Bangiales and Hildenbrandiales. However, the presence of an unclassified intron at position 989 in a collection of H. rubra from British Columbia was noted. This intron is a member of the IE subclass and is the first report of this intron type in the red algae. Phylogenetic analyses of the intron sequences revealed a close relationship between this IE intron inserted at position 989 and similar fungal IE introns in positions 989 and 1199. The 989 IE introns formed a moderately to well‐supported clade, whereas the 1199 IE introns are weakly supported. Unique structural helices in the P13 domain of the 989 and 1199 IE introns also point to a close relationship between these two clades and provide further evidence for the value of secondary structural characteristics in identifying homologous introns in evolutionarily divergent organisms. The absence of the 989 IE intron in all other red algal nuclear SSU rRNA genes suggests that it is unlikely that this intron was vertically inherited from the common ancestor of the red algal and fungal lineages but rather is the result of lateral transfer between fungal and red algal nuclear SSU rRNA genes.
EXPERIMENTAL EVIDENCE SUPPORTS THE USE OF δ15N CONTENT OF THE OPPORTUNISTIC GREEN MACROALGA ENTEROMORPHA INTESTINALIS (CHLOROPHYTA) TO DETERMINE NITROGEN SOURCES TO ESTUARIES1
Authors: Cohen R. A. , Fong P.
Published: March 2005

One assumption underlying the use of stable nitrogen isotopes (δ15N) for determining nitrogen (N) sources is that the δ15N of primary producers reflects N sources in a predictable manner. To test this assumption, we conducted two experiments. First, we varied δ15N with constant concentration of NO3− or NH4+ to determine whether either nutrient is preferentially selected by the macroalga Enteromorpha intestinalis (L. Link) and if isotopic ratio affected selectivity. Tissue δ15N increased with δ15N supplied for both NO3− and NH4+ but sequestering of 15NH4+ was more rapid than for 15NO3−; in addition, some evidence suggested that high relative abundance of 15N may have decreased NO3− uptake. Second, we held δ15N constant and varied concentrations of either NO3− or NH4+ to determine whether fractionation is concentration dependent. Uptake of N was described by a Michaelis‐Menten equation for both NO3− and NH4+, with higher Vmax and K1/2 for NH4+ than for NO3−. There was no relationship between N concentration and tissue δ15N for either NO3− or NH4+; therefore, no selection for 14N over 15N occurred. This study demonstrated that accumulation of 15N in macroalgal tissue was predictable over a range of water δ15N values and N concentrations, suggesting that E. intestinalis may be used to assess the availability of N sources to estuarine and coastal communities. However, caution must be used when interpreting tissue δ15N depending on the primary inorganic form of N available.
INDUCTION OF VACUOLATED SPHEROPLASTS AND ISOLATION OF VACUOLES IN CYANOBACTERIA1
Authors: Yi Ping , Zhao Yi‐jun , Guo Hou‐liang
Published: March 2005

There is still a great deal of debate about whether cyanobacteria contain vacuoles. This might in part reflect our limited ability to isolate vacuoles. We found and isolated vacuoles from different cyanobacteria during spheroplast preparation. Lysozyme treatment induced two kinds of spheroplasts: vacuolated spheroplasts and nonvacuolated spheroplasts. Upon breakage in distilled water, vacuolated spheroplasts released transparent, spherical, and colorless vacuoles with diameters ranging from 2.3 to 16 μm. Large vacuoles could be generated by fusion of two or three small vacuoles. Additionally, large vacuoles also could engulf small ones or other cellular bodies. The isolated vacuoles could tolerate hypotonic condition, and some could be drawn into a thread. Nonvacuolated spheroplasts released few vacuoles after breaking apart. This successful confirmation and isolation of vacuoles will allow studies of the origin and function of cyanobacterial vacuoles.
MORPHOLOGICAL AND MOLECULAR ANALYSIS OF THE ENDANGERED SPECIES PORPHYRA TENERA (BANGIALES, RHODOPHYTA)1
Authors: Niwa Kyosuke , Kikuchi Norio , Aruga Yusho
Published: March 2005

Porphyra tenera Kjellman, widely cultivated in nori farms before the development of artificial seeding, is currently listed as an endangered species in Japan. To confirm whether a wild‐collected gametophytic blade was P. tenera or the closely related species P. yezoensis Ueda, morphological observations and molecular analyses were made on the pure line HGT‐1 isolated from a wild blade. This pure line was identified as P. tenera based on detailed morphological features. Sequences of the nuclear internal transcribed spacer region 1 and the plastid RUBISCO spacer revealed that P. tenera HGT‐1 was clearly different from P. yezoensis f. narawaensis Miura, the main species cultivated in Japan. PCR‐RFLP analysis of the internal transcribed spacer region was found to be a convenient method for rapid discrimination between P. tenera and cultivated P. yezoensis. The restriction patterns generated by the endonucleases Dra I and Hae III were useful for differentiating between both gametophytic and conchocelis stages of P. tenera HGT‐1 and P. yezoensis f. narawaensis strains. Thus, PCR‐RFLP analysis will serve as a valuable tool for rapid species identification of cultivated Porphyra strains, culture collections of Porphyra strains for breeding material and conservation of biodiversity, and, as codominant cleaved amplified polymorphic sequence markers for interspecific hybridization products between P. tenera and P. yezoensis f. narawaensis. Under the same culture conditions, rate of blade length increase and the blade length‐to‐width ratio were lower in P. tenera HGT‐1 than in P. yezoensis f. narawaensis HG‐4. The HGT‐1 became mature more rapidly than HG‐4 and had thinner blades.
MOLECULAR AND MORPHOLOGICAL CHARACTERIZATION OF TEN POLAR AND NEAR‐POLAR STRAINS WITHIN THE OSCILLATORIALES (CYANOBACTERIA)1
Authors: Casamatta Dale A. , Johansen Jeffrey R. , Vis Morgan L. , Broadwater Sharon T.
Published: March 2005

An approximately 1400‐bp region of the 16S rRNA gene was sequenced for 10 polar or near‐polar strains putatively placed in the Oscillatorialean genera Oscillatoria, Phormidium, and Lyngbya obtained from the University of Toronto Culture Collection to assess phylogenetic relationships. The strains were also examined for thylakoid structure and cell division type with TEM as well as traditional morphology with LM. Phylogenetic trees constructed using parsimony, distance, and maximum likelihood methods were similar in topology. If the original epithets applied to the sequenced strains (both polar and those from GenBank) were used, it was clear that taxa were not monophyletic. However, using the revised taxonomic system of Anagnostidis and Komárek, we were able to reassign these strains to their current correct taxa (species, genus, and family). When these assignments were made, it was determined that the molecular sequence data analyses were congruent with morphology and ultrastructure. Nine of the polar strains were found to be new species, and eight were described as such: Arthronema gygaxiana Casamatta et Johansen sp. nov., Pseudanabaena tremula Johansen et Casamatta sp. nov., Leptolyngbya angustata Casamatta et Johansen sp. nov., Phormidium lumbricale Johansen et Casamatta sp. nov., Microcoleus glaciei Johansen et Casamatta sp. nov., Microcoleus rushforthii Johansen et Casamatta sp. nov., Microcoleus antarcticus Casamatta et Johansen sp. nov., Microcoleus acremannii Casamatta et Johansen sp. nov. Some genera (Leptolyngbya and Microcoleus) were clearly not monophyletic and require future revision.
LIPID COMPOSITION OF CHLORARACHNIOPHYTES (CHLORARACHNIOPHYCEAE) FROM THE GENERA BIGELOWIELLA, GYMNOCHLORA, AND LOTHARELLA1
Authors: Leblond Jeffrey D. , Dahmen Jeremy L. , Seipelt Rebecca L. , Elrod‐Erickson Matthew J. , Kincaid Rodney , Howard James C. , Evens Terence J. , Chapman Peter J.
Published: March 2005

The Chlorarachniophyceae are unicellular eukaryotic algae characterized by an amoeboid morphology that may be the result of secondary endosymbiosis of a green alga by a nonphotosynthetic amoeba or amoeboflagellate. Whereas much is known about the phylogeny of chlorarachniophytes, little is known about their physiology, particularly that of their lipids. In an initial effort to characterize the lipids of this algal class, four organisms from three genera were examined for their fatty acid and sterol composition. Fatty acids from lipid fractions containing chloroplast‐associated glycolipids, storage triglycerides, and cytoplasmic membrane‐associated polar lipids were characterized. Glycolipid‐associated fatty acids were of limited composition, principally eicosapentaenoic acid [20:5(n‐3)] and hexadecanoic acid (16:0). Triglyceride‐associated fatty acids, although minor, were found to be similar in composition. The polar lipid fraction was dominated by lipids that did not contain phosphorus and had a more variable fatty acid composition with 16:0 and docosapentaenoic acid [22:5(n‐3)] dominant along with a number of minor C18 and C20 fatty acids. Crinosterol and one of the epimeric pair poriferasterol/stigmasterol were the sole sterols. Several genes required for synthesis of these sterols were computationally identified in Bigelowiella natans Moestrup. One sterol biosynthesis gene showed the greatest similarity to SMT1 of the green alga, Chlamydomonas reinhardtii. However, homologues to other species, mostly green plant species, were also found. Further, the method used for identification suggested that the sequences were transferred to a genetic compartment other than the likely original location, the nucleomorph nucleus.
INORGANIC CARBON REPLETION DISRUPTS PHOTOSYNTHETIC ACCLIMATION TO LOW TEMPERATURE IN THE CYANOBACTERIUM SYNECHOCOCCUS ELONGATUS1
Authors: Burns Robert A. , MacDonald C. Danielle , McGinn Patrick J. , Campbell Douglas. A.
Published: March 2005

Acclimation of cyanobacteria to ambient fluctuations in inorganic carbon (Ci) and temperature requires reorganization of the major protein complexes involved in photosynthesis. We grew cultures of the picoplanktonic cyanobacterium Synechococcus elongatus Naegeli across most of its range of tolerable temperatures from 23 to 35°C at both low (<0.1 mM) and high Ci (approximately 4 mM). Over that range of temperatures, the chl‐based doubling time did not differ between low and high Ci grown cells but did increase with decreasing temperature. Cells grown at 23°C high Ci showed an elongated morphology, which was not present in 23°C low Ci cells nor at 35°C high and low Ci. Furthermore, 23°C high Ci cells showed premature senescence and death compared with all other treatments. Phycocyanin per cell was greater in high Ci grown cells at all temperatures but showed a characteristic decrease with decreasing temperature. Functional PSII determination showed that 23°C high Ci cells had 1.5 × 105 PSII·cell–1 compared with only 6.9 × 104 PSII·cell–1 for 23°C low Ci. The 35°C high and low Ci cells had 7.7 × 104 and 6.4 × 104 PSII·cell–1, respectively. These data were supported by immunoblot determinations of PsbA content·cell–1. As a result of their high PSII·cell–1, 23°C high Ci cells generated more reductant from PSII than could be accommodated by downstream assimilative metabolism, resulting in early senescence and death of 23°C high Ci cells, probably as a result of the generation of reactive byproducts of electron transport.
DETECTION OF A GROUP I (IE) FUNGAL INTRON IN THE GREEN ALGAL GENUS UROSPORA (ULVOPHYCEAE)1
Authors: Lindstrom Sandra C. , Pistolic Jelena
Published: March 2005

A group IE intron at position 989 (Escherichia coli numbering) in the 18S rRNA gene is described for the first time from the green algae based on primary and secondary structure analysis of the intron. The intron occurred in Urospora neglecta Kornmann, U. wormskioldii (Mertens) Rosenvinge, and in an undescribed taxon closely allied with U. wormskioldii. The Urospora intron was 397 or 399 bp in length, except for one variant, which was 652 bp in length. The latter intron appeared to be a chimera, consisting of a conspecific part, a segment more closely related to another species, and a region of unknown origin. A search of data bases containing introns indicated that the green algal intron is homologous with other 989 introns, all occurring in fungi, which may be the source of the Urospora intron. The introduction of this intron into the Urospora lineage has occurred within the last 14 million years, based on estimates of the earliest divergence of the genus from other members of the family Acrosiphoniaceae, all of which lack 18S introns.
EFFECTS OF UV‐B RADIATION ON THE D1 PROTEIN REPAIR CYCLE OF NATURAL PHYTOPLANKTON COMMUNITIES FROM THREE LATITUDES (CANADA, BRAZIL, AND ARGENTINA)1
Authors: Nina Bouchard Josée , Campbell Douglas A. , Roy Suzanne
Published: March 2005

Ultraviolet radiation effects were examined in natural phytoplankton communities from Rimouski (Canada), Ubatuba (Brazil), and Ushuaia (Argentina). Outdoor pump‐mixed mesocosms were submitted to ambient solar radiation (NUVB) and ambient with additional UV‐B radiation (UVBR) from lamps (HUVB), corresponding to a local 60% ozone depletion scenario. At all sites, neither algal biomass nor dark‐adapted Fv/Fmwere significantly affected by additional UVBR, suggesting the presence of active UV protection or repair mechanisms. To examine the role of D1 protein turnover, essential for PSII repair, short‐term surface incubations were performed in the presence or absence of lincomycin, a chloroplast protein synthesis inhibitor. Effects on PSII were determined using chl a in vivo fluorescence, whereas the D1 protein was detected immunochemically. In the absence of D1 repair, D1 pools and Fv/Fmdecreased to a similar extent under both light treatments. In the presence of D1 repair, D1 pools suffered faster net degradation under HUVB compared with NUVB, whereas Fv/Fmwas maintained for both light treatments, suggesting that HUVB exposure in field populations had more effect on D1 synthesis and PSII repair than on D1 degradation. The fewer undamaged reaction centers remaining in phytoplankton under HUVB were able to maintain Fv/Fmor actually recovered during the dark acclimation before Fv/Fmmeasurements. The D1 pools suffered faster net degradation at the tropical site where high irradiance drove faster D1 degradation and high water temperature enabled fast enzymatic activities. This study shows the crucial role of dynamic changes in D1 turnover in the photobiology of natural planktonic communities across a range of latitudes.
MONITORING RAPID VALVE FORMATION IN THE PENNATE DIATOMNAVICULA SALINARUM(BACILLARIOPHYCEAE)1
Authors: Hazelaar Sandra , Van Der Strate Han J. , Gieskes Winfried W. C. , Vrieling Engel G.
Published: March 2005

After each division of a diatom cell, a new siliceous hypovalve is formed inside the silica deposition vesicle (SDV). We present the sequence of this early formation of the new valve in the pennate marine diatomNavicula salinarum(Grunow) Hustedt, visualized by using the fluorescent probe 2‐(4‐pyridyl)‐5‐((4‐(2‐dimethylaminoethylamino‐carbamoyl)methoxy)phenyl)oxazole (PDMPO). Our observations confirm that two‐dimensional expansion of the growing valve is a rapid process of no more than 15 min; three‐dimensional completion of the valve appears to be slower, lasting most of the time valve formation takes. The results are relevant to studies of the timing of molecular processes involved in valve formation (i.e. the bio‐ and morphogenesis of the SDV) in relation to uptake and transport of silicic acid. Use of this probe helps us to identify specific developmental stages for further detail analysis of diatom basilica formation, which eventually could lead to obtaining enriched SDV fractions.
SPECTRAL FINGERPRINTING OF ALGAL COMMUNITIES: A NOVEL APPROACH TO BIOFILM ANALYSIS AND BIOMONITORING1
Authors: Larson Chad , Passy Sophia I.
Published: March 2005

A new technique for spectral fingerprinting of major algal groups in the freshwater periphyton (i.e. cyanobacteria, green algae, and diatoms) was developed using confocal laser scanning microscopy. This technique used the differential spectral emission signatures of photosynthetic algae and allowed their spatially explicit quantification and community three‐dimensional reconstruction. Algal biovolume measurements, carried out with this technique, are superior to existing protocols involving chl and ash‐free dry mass assessments because they are nondestructive, localized, and specific at a group level. This technique can be used to generate depth profiles of the periphytic mat with various applications in aquatic ecology and biofilm analysis.
SYSTEMATICS OFGRATELOUPIA FILICINA(HALYMENIACEAE, RHODOPHYTA), BASED ONrbcL SEQUENCE ANALYSES AND MORPHOLOGICAL EVIDENCE, INCLUDING THE REINSTATEMENT OFG. MINIMAAND THE DESCRIPTION OFG. CAPENSISSP. NOV.1
Authors: De Clerck Olivier , Gavio Brigitte , Fredericq Suzanne , Bárbara Ignacio , Coppejans Eric
Published: March 2005

Grateloupia filicina(C. Agardh) Lamouroux, originally described from the Mediterranean Sea, has long been considered a textbook example of a marine red alga with a cosmopolitan distribution. AnrbcL‐based molecular phylogeny, encompassing samples covering the entire geographic distribution of the species, revealed a plethora of “cryptic” species, whereby the presence of genuineG. filicinais limited to the Mediterranean basin. The phylogeny revealed a strong biogeographic imprint, with specimens from temperate regions resolved in clades composed of species inhabiting the same geographic region. Presence of widely divergent morphologies in the temperate clades indicated that several lineages have converged independently to aG. filicina‐type morphology. Tropical representatives are resolved in a single clade with very uniformG. filicina‐type morphology and pairwise sequence divergences that are lower than the average divergence observed in temperate lineages. This, combined with a lack of clear geographic structure among the tropical lineages, may indicate a more recent divergence with long‐range dispersal capacities. Violations to the biogeographic signal in temperate lineages seemed to be due to either inadequate taxonomy or recent introductions.Grateloupia minimaP. & H. Crouan, a taxon placed in synonymy underG. filicina, is reinstated as a separate species distributed in the northeast Atlantic Ocean.Grateloupia capensissp. nov. is described to accommodate specimens from South Africa with aG. filicina‐type morphology, andG. filicinavar.luxuriansis elevated to species status. Morphological and anatomical characters were put forward that support the distinctiveness of these three distinct species.
Bacterial vaginosis – a laboratory and clinical diagnostics enigma
Authors: FORSUM URBAN , HALLÉN ANDERS , LARSSON P. G.
Published: March 2005

Diagnosing bacterial vaginosis (BV) has long been based on the clinical criteria of Amsel et al., whereby three of four defined criteria must be satisfied. Though there are other criteria and scoring methods which function well in comparison (i.e. Nugent scoring), it is not certain that they will always identify the same category of patients. Point‐of‐care methods based on various combinations of microbial products, presence of RNA, or more complex laboratory instrumentations such as sensor arrays, have also been introduced for the diagnosis of BV. No method for diagnosing BV can at present be regarded as the best. It could be that – based partly on tacit knowledge on the part of the clinical investigators scoring in the clinic – various scoring systems have been chosen to fit a particular BV‐related problem in a particular population. In this review we critically examine these pertinent issues influencing clinical scoring and laboratory diagnostics of BV.
Complement activation in acute coronary syndromes
Authors: ILTUMUR KENAN , KARABULUT AZIZ , TOPRAK GÜLTEN , TOPRAK NIZAMETTIN
Published: March 2005

The complement system is part of the host defence response. However, considerable evidence suggests that complement plays an important role in the pathophysiology of ischemic heart disease. The aim of this study was to evaluate complement activation in patients with all forms of acute coronary syndromes (ACS) and to examine the relationship between the degree of complement activation and myocardial injury. The study population included 152 subjects (26 females): 82 with ACS (35 acute myocardial infarction (AMI), 22 non‐Q wave MI (NQMI), 25 unstable angina (UAP)) (Group A), 35 stable angina (SA) (Group B), and 35 healty control subjects (Group C). Complement 3 (C3), Complement 4 (C4), C‐reactive protein (CRP), troponin I (TnI) as well as creatine kinase MB (CK‐MB) were evaluated. Patients' blood samples were taken on admission (day 1) and after 2, 3 and 7 days in group A. However, only one measurement was performed in the groups B and C. Plasma C3 and C4 peak levels were significantly higher in patients with AMI (141±29 and 35±11 mg/dl) and NQMI (136±13 and 35±7 mg/dl) than in patients with SA (128±14 and 27±10 mg/dl) and the control subjects (114±22 and 22±7 mg/dl) (p<0.03). Also, C3 and C4 serum levels in patients with SA and UAP (126±16 and 31±7 mg/dl) were significantly higher than those in control subjects (p<0.01, p<0.03, respectively). At 1‐week follow‐up, there were no significant differences between the plasma levels of C3 and C4 in patients with UAP (p>0.05). However, plasma levels of C3 and C4 were significantly different between days in patients with AMI and NQMI (p<0.0001). Plasma C3 and C4 levels in ACS showed a relationship with peak CK‐MB and Tn I levels (p<0.01). Plasma CRP level in ACS showed positive correlation with C3 (p<0.01) and C4 (p<0.001). In this study, we determined that plasma C3 and C4 levels were elevated in ACS and SA. Although C3 and C4 were higher in ACS and SA, the systemic levels of inflammatory markers in patients with SA and UAP were lower than those found in the AMI and NQMI groups. The relationship between C3, C4 levels and ACS further suggests that the complement activation is related to necrosis within the myocardium.
Comparison of HER‐2/neu, ER and PCNA expression in premenopausal and postmenopausal patients with breast carcinoma
Authors: ZHENG WEIQIANG , ZHENG JIANMING , MA LONG , MENG FENGFANG , HUANG LING , MA DALIE
Published: March 2005

We attempted to compare the pattern of HER‐2/neu, ER and PCNA in premenopausal and postmenopausal patients with breast carcinoma to identify potential biological differences. Five hundred and forty‐eight samples from 318 premenopausal and 230 postmenopausal women with invasive ductal carcinoma of the breast were evaluated for HER‐2/neu, ER and PCNA expression by immunohistochemistry. HER‐2/neu expression showed 27.4% positivity in premenopausal and 24.8% in postmenopausal women; there was no significant difference between the two groups (p>0.05). In contrast, HER‐2/neu expression was found to be significantly associated with ER negativity in the two groups (p<0.05 in premenopausal, p<0.001 in postmenopausal patients). However, it was significantly associated with PCNA expression only in the postmenopausal group (p<0.001). 54.4% showed premenopausal tumor cell ER positivity, whereas 64.3% of the postmenopausal group showed positivity. ER expression showed a significant correlation with patient menopausal status (p<0.05). The prevalence of PCNA positivity in the tumor cell components is slightly higher in postmenopausal compared to premenopausal women (p>0.20).The current study is consistent with reports from other groups regarding the correlation of HER‐2/neu with adverse pathologic features and with expression of other markers in carcinoma. We also observed there was no trend toward increased HER‐2/neu expression in either premenopausal or postmenopausal patients, i.e. there was similar HER‐2/neu expression in the two groups. This suggests that HER‐2/neu status could be used to determine assignment to specific intensive adjuvant therapy and evaluation of biological behavior in both pre‐ and postmenopausal patients with breast carcinoma.
Pharyngeal carriage of serogroup W135 Neisseria meningitidis in Hajjees and their family contacts in Morocco, Oman and Sudan
Authors: NICOLAS P. , M'BAREK N. AIT , AL‐AWAIDY S. , BUSAIDY S. AL , SULAIMAN N. , ISSA M. , MAHJOUR J. , MÖLLING P. , CAUGANT D. A. , OLCÉN P. , SANTAMARIA M.
Published: March 2005

In 2000 the global outbreak that began in Saudi Arabia was caused by a W135:2a:P1.5,2 strain of Neisseria meningitidis belonging to the ET‐37 complex and to ST‐11. There was concern that introduction of this epidemic clone (EC) might lead to a wave of outbreaks in the African meningitis belt. The WHO therefore initiated studies of meningococcal carriage among pilgrims and their family contacts in Morocco, Oman and Sudan, 3 to 12 months after the Hajj 2000. In Morocco, 1186 persons were swabbed 3 times. Ninety‐five meningococcal strains were isolated from 2.7% of the specimens. Pulsed‐field gel electrophoresis showed that 32 (33.6%) were identical with the EC. In Sudan, 5 strains identical with the EC were obtained after sampling 285 persons. In Oman, among 18 meningococcal strains isolated from 399 subjects, 11 (61.1%) belonged to the EC. The important pharyngeal carriage of W135 (EC) and its role in the 2001–2002 outbreaks in Burkina Faso argues for the necessity of reinforcing surveillance, and adapting and planning responses in Africa and the Middle East using the most appropriate vaccine.
Carbapenem resistance mechanisms in Pseudomonas aeruginosa: alterations of porin OprD and efflux proteins do not fully explain resistance patterns observed in clinical isolates
Authors: AMIN NAGWA EL , GISKE CHRISTIAN G. , JALAL SHAH , KEIJSER BERIT , KRONVALL GÖRAN , WRETLIND BENGT
Published: March 2005

Imipenem resistance in Pseudomonas aeruginosa is considered to be associated with loss of the porin OprD combined with activity of chromosomal β‐lactamase (AmpC), while overexpression of multidrug efflux pumps is considered to confer meropenem resistance. Carbapenem resistance can also result from production of metallo‐β‐lactamases. Transcription of oprD and efflux pump genes mexB, mexY and mexF was analysed in 23 clinical isolates of P. aeruginosa by quantitative RT‐PCR. oprD was sequenced in all, and mexR, regulator of efflux pump MexAB‐OprM, in selected isolates. Four isolates that were imipenem susceptible had significant reduction of oprD mRNA and presence of oprD mutations causing frameshift or translational stop. In strains only resistant to imipenem no significant difference in transcription of oprD was observed between low‐level and high‐level resistant isolates. The differences could not be explained by either pattern of oprD mutations. Increased transcription of mexB generally correlated well with meropenem resistance. One high‐level meropenem‐resistant isolate showed no signicant change in mexB mRNA, but sequencing confirmed presence of a nalB mutation. Furthermore, one meropenem‐susceptible isolate showed significant increase in mexB transcription, but no mexR mutations. In summary, our findings indicate that the resistance patterns observed cannot be fully explained by the currently described carbapenem resistance mechanisms.
Cross‐reactivity between human adenoviruses in delayed‐type hypersensitivity
Authors: BAKAY MARTA , SZALAY KATALIN , BELADI ILONA , BALINT ELISABETH , LENGYEL ANNA , ADAM EVA , OLAH TIBOR
Published: March 2005

The aim of this study was to determine the antigen responsible for the induction of delayed‐type hypersensitivity (DTH) by human adenoviruses (Ads). The estimation of DTH was based on measurement of the extent of swelling of the hind footpads of mice. CsCl density gradient‐purified human Ad serotype 6 (Ad6) induced DTH in a dose‐dependent manner. In Ad6‐sensitized mice, DTH could be elicited by serotypes belonging to the same species of human Ads (types 1 and 5) and by a serotype (type 3) belonging to another species. Latex particles coated with purified hexon antigen prepared from Ad5 had the capacity to sensitize mice and elicit a DTH reaction. We suggest that, for serotypes belonging to species C, the cross‐reactive highly conserved T cell epitope of the hexon protein might be responsible for the DTH induction, and furthermore the same epitope might result in the cross‐reactivity between serotypes 3 and 6. The possible importance of these data is discussed in relation to human gene therapy through the application of Ad vectors.
Weekly point prevalence of Streptococcus pneumoniae, Hemophilus influenzae and Moraxella catarrhalis in the upper airways of normal young children: effect of respiratory illness and season
Authors: HENDLEY J. OWEN , HAYDEN FREDERICK G. , WINTHER BIRGIT
Published: March 2005

The aim was to determine the effect of respiratory illness and season on carriage rates in the upper airways of Streptococcus pneumoniae, Hemophilus influenzae and Moraxella catarrhalis in normal children. Sixteen healthy children, 1–10 years old, amenable to weekly sampling were followed longitudinally for at least three seasons of the year. Respiratory symptoms were recorded daily; weekly nasal aspirate/wash samples were cultured on selective agars. Urea concentration in samples was used to define dilution of secretion. 68% of 950 samples were culture positive; 44% of positives had two or all three species. Each species was detected in about one third of samples. Bacteria were detected in 76% of samples during illness vs. 65% during wellness (p=0.004). Seasonal carriage rates varied from 56% in summer and fall to 85% in winter. There was a strong inverse correlation between dilution of secretion and bacterial detection rate in illness and wellness aspirate samples during the four seasons (r=−0.82, p=0.01). Detection of bacteria varied with the amount of secretion in the sample. This variation accounts for the apparent differences in bacterial carriage during illness vs. wellness and during different seasons.
Brain abscess due to Actinobacillus actinomycetemcomitans
Authors: STEPANOVIĆ SRDJAN , TOŠIĆ TANJA , SAVIĆ BRANISLAVA , JOVANOVIĆ MILICA , K'OUAS GUYLÈNE , CARLIER JEAN‐PHILIPPE
Published: March 2005

Actinobacillus actinomycetemcomitans, a constituent of the oral flora, is a rare cause of brain abscesses. We report the case of a 47‐year‐old male who presented with multiple brain abscesses due to this organism, presumably originating from his poor dentition. Problems met in isolating and identifying A. actinomycetemcomitans suggest that its true rate of isolation from non‐oral samples may have been underestimated.
Efficacy of Listerine® Antiseptic in reducing viral contamination of saliva
Authors: Meiller Timothy F. , Silva Arley , Ferreira Sonia M. , Jabra‐Rizk Mary Ann , Kelley Jacqueline I. , DePaola Louis G.
Published: March 2005

Aim: The anti‐viral efficacy of oral antimicrobial rinses has not been adequately studied in terms of potential clinical significance. As a follow‐up to an in vitro study on the effect of oral antiseptics on Herpes simplex virus, Type 1, this study was undertaken to evaluate the in vivo effect of an essential oil containing oral antiseptic on the reduction of viral titer in saliva during active viral infection.

Method: Patients were recruited and evaluated in a single visit protocol at the onset of a perioral outbreak, consistent historically and clinically with recurrent Herpes labialis. Direct immunofluorescence of cytological smears of the lesions/oral fluids was used to confirm Herpes simplex virus types I or II. Patients were randomly assigned to one of two treatment groups: (1) active ingredient and (2) sterile water control. The viral lesion was evaluated as to clinical stage according to standard protocol. Salivary fluid samples were taken: (1) at baseline; (2) immediately following a 30 s rinse; (3) 30 min. after the 30 s rinse; and (4) on the repeat trial, also at 60 min. after the 30 s rinse. All samples were evaluated for viral titer and results compared.

Results: In Trial 1, the sample population consisted of 19 males and 21 females with an average age of 29.2 and in Trial 2, 21 males, 19 females with an average age of 28. In both Trials 1 and 2, recoverable infectious virions were reduced to zero after a 30 s experimental rinse; whereas, the control rinse resulted in a non‐significant (p>0.05) reduction. The experimental group also demonstrated a continued significant (p<0.05) reduction 30 min. post rinse when compared with baseline while the control group returned to baseline levels. In Trial 2, the 60 min. post rinse follow‐up demonstrated a 1–2 log residual reduction from baseline in the experimental group; however, this was not significant.

Conclusions: There is clinical efficacy in utilizing an oral rinse with the antimicrobial agent Listerine® Antiseptic in reducing the presence of viral contamination in oral fluids for at least 30 min. after oral rinse. The risk of viral cross contamination generated from these oral fluids in person to person contact or during dental treatment may be reduced.
Relationship between attitudes toward oral health at initial office visit and compliance with supportive periodontal treatment
Authors: Ojima M. , Kanagawa H. , Nishida N. , Nagata H. , Hanioka T. , Shizukuishi S.
Published: March 2005

Objectives: The objectives of the present study include investigation of the relationship between attitudes and desires with respect to oral health at initial office visit and compliance with supportive periodontal treatment (SPT) and identification of prognostic factors with respect to low‐compliance with SPT.

Materials and Methods: Four hundred thirty‐one patients were evaluated. Subjects completed a questionnaire concerning attitude and desire with respect to oral health and subjective symptoms prior to periodontal treatment. Survival probabilities of SPT were estimated by the Kaplan–Meier method and compared between answers for each item of the questionnaire via the Cox–Mantel test. Finally, a multivariate Cox proportional hazards regression model was constructed, which included age and gender.

Results: Greater than 95% of participants desired toothbrushing proficiency and lifelong retention of teeth at the initial office visit; however, the overall survival probabilities of SPT were only 52.7% after about 5 years. Patients exhibiting unfavourable attitudes toward oral health at the initial office visit, in comparison with those displaying favourable attitudes, exhibited greater tendency to abandon SPT. A Cox regression model revealed that lack of brushing on the gingival margin, non‐use of an inter‐dental brush or dental floss, non‐use of fluoride toothpaste and frequent consumption of sugar‐containing drinks were significant independent prognostic factors for low‐compliance with SPT (p<0.05; Hazard ratios=2.27, 2.00, 2.56 and 2.06, respectively).

Conclusions: Desire for satisfactory oral health is not related consistently to continuation of SPT. Unfavourable attitudes toward oral health were correlated to low‐compliance with SPT. Clinicians may wish to establish methods for improvement of patient compliance employing behavioural approaches applicable to the attitudes of potential low‐compliance individuals.
A 0.05% cetyl pyridinium chloride/0.05% chlorhexidine mouth rinse during maintenance phase after initial periodontal therapy
Authors: Quirynen Marc , Soers Catherine , Desnyder Mandy , Dekeyser Christel , Pauwels Martine , Van Steenberghe Daniel
Published: March 2005

Background: Chlorhexidine (CHX) mouth rinse/spray can still be considered the gold standard in the chemical prevention of plaque formation and development of gingivitis. The product unfortunately has some side effects, such as extrinsic tooth staining, poor taste, taste disturbance, sensitivity changes in tongue, pain and irritation because of the alcohol content. These side effects led to the search of new formulations.

Methods: In this double‐blind, randomized, long‐term, parallel study, 48 moderate periodontitis patients rinsed for 6 months (starting immediately after a “one‐stage, full‐mouth” disinfection) with one of the following products: CHX 0.2%+alcohol (Corsodyl®), CHX 0.05%+ cetyl pyridinium chloride (CPC) 0.05% and no alcohol (Perio‐Aid Maintenance®, a new formulation), or the placebo of the latter. After 1, 3 and 6 months a series of clinical and microbiological parameters were recorded for the supra‐ and subgingival area as well as for saliva.

Results: Although there was a significant treatment impact (mechanical debridement) in all groups, both CHX solutions further decreased both plaque and gingivitis indices (p<0.001 and p<0.05, respectively), when compared with placebo. This was also reflected by additional reductions in the number of CFU/ml of aerobic and especially anaerobic species and by a suppression of Streptococcus mutans (versus an overgrowth for the placebo), in all niches. Differences between both CHX solutions were never encountered. The subjective ratings were slightly in favour of the new CHX–CPC formulation when compared with the other CHX–alcohol formulation, especially for taste of the product (p<0.05), but less impressive for the staining of teeth and tongue.

Conclusions: The results of this study demonstrated the potential of a new CHX 0.05%+CPC 0.05% non‐alcoholic formulation as an effective antiplaque agent for long‐term use with reduced subjective side effects.
Gingivo‐mucosal and cutaneous reactions to amalgam fillings
Authors: Fardal Øystein , Johannessen Anne C. , Morken Tore
Published: March 2005

Background:A number of reports exist on the side effects of materials used to restore teeth. Most of the cases involve local allergy reactions, but also skin lesions are described. Few cases are described where both local effects on the mucosa and skin lesions distant to the oral cavity are caused by amalgam.

Result:The case presented indicates that the release of mercury from amalgam fillings is able to induce hypersensitivity reactions resulting in soft‐tissue changes in the gingiva, buccal mucosa, tongue and on the skin of the back of the hands.
Interest in periodontology and preferences for treatment of localized gingival recessions
Authors: Zaher C.‐A. , Hachem J. , Puhan M. A. , Mombelli A.
Published: March 2005

Objectives: The purpose of this study was to evaluate the views, knowledge and preferences of a large sample of practising dentists in periodontics, focusing specifically on the treatment of gingival recessions, and to compare the findings with the current evidence available in the dental literature.

Methods: We conducted a cross‐sectional postal survey of 3780 dentists, representing the majority of all dentists working in Switzerland. The questionnaire consisted of 17 questions, most of them giving the possibility of multiple choices of answers. The demographic profile, interests and satisfaction in periodontics were associated with the choice of treatment options offered for the management of six clinical situations.

Results: One thousand two hundred and one dentists sent back the questionnaire within three months and were thus included in the analysis. In general, the interest and the satisfaction in periodontics were moderate to high (6–7 on an analogue scale from 1 to 10). Specialists in periodontics indicated a significantly higher interest and satisfaction in periodontics than the general dentists (p<0.001), and practitioners working in urban areas indicated a slightly higher interest (p=0.027) and satisfaction (0.047) than their colleagues established in a rural setting. The predominant indication of root coverage procedures was aesthetics (90.7%). The region in which dentists worked was the only significant predictor for choosing “no treatment” of buccal recessions: dentists from the German‐speaking part were significantly less inclined to surgically treat gingival recessions than their colleagues from the French or Italian part. For those who opted for therapy, a free tissue graft was generally the favourite option, followed by a connective tissue graft and a coronally advanced flap. Throughout, only a small fraction of the dentists considered using a guided tissue regeneration procedure. The relative odds for not extracting teeth with severe periodontal disease were higher if the dentist was a specialist than a generalist. Satisfaction in practicing periodontics also positively strengthened the inclination towards keeping severely compromised teeth.

Conclusions: Aesthetic concerns were the predominant indication for root coverage procedures. Further research should therefore include aesthetic aspects as primary clinical outcome variables. Specific training of dentists and their satisfaction in periodontics influenced treatment decisions. Specialists involved in continuing education should inform practicing dentists more efficiently on the potential and usefulness of periodontal therapy for saving and maintaining periodontally compromised teeth.
A new ultrasonic device in maintenance therapy: perception of pain and clinical efficacy
Authors: Kocher Thomas , Fanghänel Jutta , Schwahn Christian , Rühling Andreas
Published: March 2005

Background: A recently introduced piezo‐driven ultrasonic device (Vector®) generates longitudinal oscillations. As a result, the instrument tip moves parallel to the tooth surface. By avoiding vertical oscillations, maintenance treatment with the Vector® device should be less painful than treatment with conventional systems. We investigated whether patients perceive treatment with the Vector® device as less painful than with a conventional ultrasonic device, and whether the clinical efficacy of the Vector® device is comparable with that of the conventional ultrasonic device in maintenance patients.

Material and methods: Thirty‐eight maintenance patients with moderate to advanced periodontal disease took part in this prospective, randomized controlled clinical study. Each patients had to have at least two teeth with probing depths of >4 mm. They were treated either with Dentsply® (n=22) at a reduced power setting or with the Vector® device (n=16). The observation period was 6 months. Probing pocket depth, attachment level, and bleeding upon probing were assessed at six sites on each treated tooth by a blinded investigator Patient were asked to report perceived pain during instrumentation with a visual analog scale immediately after treatment, in the evening of the treatment day, and in the evenings 1 and 2 days after treatment.

Results: Bleeding on probing, probing depth, and attachment level improved in both instrumentation groups from baseline to month 6; however, there was no difference between the two instrumentation modalities. The patients perceived treatment with neither instrument as unpleasant, and their perception of pain intensity both during instrumentation and on the following days did not differ.

Conclusion: In maintenance therapy, clinical efficacy of the vector® device is comparable with that of conventional ultrasonic device. It makes no difference whether the ultrasonic device at a reduced power setting or the Vector® device is used, since patients perceive both instruments as causing very little pain.
Geriatric dentistry education in European dental schools
Authors: Preshaw P. M. , Mohammad A. R.
Published: March 2005

Abstract  As the numbers of elderly adults continue to grow within European populations, the need for dental students to be trained in the management of geriatric patients becomes increasingly important. Many dental schools have developed training programmes in geriatric dentistry in response to the changing oral health needs of older adults. The purpose of this on‐line survey was to identify the current status of geriatric dentistry education in European dental schools. A questionnaire relating to the teaching of geriatric dentistry was posted on the Internet, and 194 dental schools in 34 European countries were invited to participate. Data from completed questionnaires were submitted to the investigators via email from 82 schools in 27 countries (42% response rate). Thirty‐six per cent of schools offered a specific geriatric dentistry course that included didactic teaching or seminar groups, 21% taught geriatric dentistry by means of organised presentations in the curriculum, and 36% taught the subject by occasional lectures. 7% of schools did not teach geriatric dentistry at all. A clinical component to the geriatric dentistry curriculum was reported by 61% of schools and 18% reported operating a specific geriatric dentistry clinic within the school. Of those providing clinical geriatric dentistry training, it was provided within the school in 45% of cases, with a further 29% of schools providing training both within the school and at a remote location. Seven per cent of schools operated a mobile dental clinic for treating geriatric patients. Twenty‐eight per cent of schools had a geriatric programme director or a chairman of a geriatric section and 39% indicated that they plan to extend the teaching of geriatric dentistry in the future. Geriatric dental education has clearly established itself in the curricula of European dental schools although the format of teaching the subject varies widely. It is of concern that geriatric dentistry was not taught at all in 7% of schools. No data are available concerning whether or not geriatric dentistry is taught in the 58% non‐responding schools.
Continuing professional development – global perspectives: synopsis of a workshop held during the International Association of Dental Research meeting in Gothenburg, Sweden, 2003. Part 1: access, funding and participation patterns
Authors: Best H. A. , Eaton K. A. , Plasschaert A. , Toh C. G. , Grayden S. K. , Senakola E. , Rohlin M.
Published: March 2005

There appears to have been little previous research interest in continuing professional development* (CPD) of dentists and the oral health team. This paper presents data and information on the following aspects of CPD in 17 countries in Asia, Australasia, Europe and North America: availability of different types of CPD, its providers, data on uptake of CPD courses and activities, and funding of CPD. The results indicate that lectures and hands‐on skills courses were held in all 17 countries but the use of the Internet to deliver CPD was by no means universal. CPD was funded from a variety of sources including universities, governments and commercial companies. However, the only universal source of funding for CPD was dentists themselves. Data on participation were available from only three countries. Research issues based on these results will be listed in a second paper.
Generalized Hydraulic Calculation Method Using Rational Polynomial Model
Authors: Pilehvari Ali A. , Serth Robert W.
Published: March 2005

A generalized hydraulic calculation technique is presented that requires, as input, only the raw rheological data for the fluid and the values of the relevant hydraulic parameters. The method utilizes a powerful new rheological model called the Rational Polynomial model, which is capable of accurately representing the rheogram of virtually any time-independent fluid. Predictions of the new method are compared with published experimental data gathered from large-scale flow loops. The tested cases include laminar and turbulent flow for a variety of drilling fluids in both pipes and concentric annuli.