bluuebunny/crossref_metadata_2025_split huggingface dataset:
FUNCTIONAL SIMILARITY AMONG ISOMORPHIC LIFE‐HISTORY PHASES OF POLYCAVERNOSA DEBILIS (RHODOPHYTA, GRACILARIACEAE) 1
Authors: Littler Mark M. , Littler Diane S. , Taylor Phillip R. 
Published: April 2007

ABSTRACT Morphologically identical but different life‐history phases of the red alga Polycavernosa debilis (Forsskål) Fredericq and J. Norris showed no conspicuous differences in physiological or ecological performances. The costs and benefits of ploidy level, as measured by net photosynthesis, calorific content, structural makeup and resistance to predation, were not sufficient to result in statistically significant differences (P > 0.05 ANOA) for the various reproductive phases [haploid male or female (including cystocarps) and diploid tetrasporic]. The lack of measurable functional responses leads to two hypotheses: (1) that adaptive ecological‐physiological differences between life‐history phases are subtle, or (2) that predominantly genetic / reproductive factors are implicated in maintaining isomorphic life‐history phases.
PHOTOSYNTHESIS AND CELL DIVISION BY ANTARCTIC MICROALGAE: COMPARISON OF BENTHIC, PLANKTONIC AND ICE ALGAE1
Authors: Rivkin Richard B. , Putt Mary 
Published: April 2007

ABSTRACTIrradiance‐dependent rates of photosynthesis and cell division of six species of microalgae isolated from the benthos, plankton and sea ice microbial community in McMurdo Sound, Antarctica were compared. Microalgae isolated from different photic environments had distinct photosynthetic and growth characteristics. For benthic and ice algae, photosynthesis saturated at 6 to 20 μE.m−2.s−1 and was photoinhibited at 10 to 80 μE.m−2.s−1 while for the planktonic algae, saturation irradiances were up to 13 times higher and photoinhibition was not detected. The slope of the light‐limited portion of the P‐I relationship was up to 50 times greater for the benthic algae than for either the ice or planktonic algae suggesting that benthic algae used the low irradiances more efficiently for carbon uptake. Cell division was dependent on the incubation irradiance for all but one microalga examined. The dependence of division rates on irradiance was however much smaller than for carbon uptake, suggesting that cell division buffers the influence of short term variations of irradiance on cellular metabolism.
TRACE METAL REDUCTION BY PHYTOPLANKTON: THE ROLE OF PLASMALEMMA REDOX ENZYMES1,2
Authors: Jones Gary J. , Palenik Brian P. , Morel François M. M. 
Published: April 2007

ABSTRACTThe phytoplankton cell surface reduces external copper(II) and iron(III) complexes and redox dyes. This reductive activity appears to be mediated by one or more plasmalemma redox enzymes. Trace metal complexes are directly reduced by the redox enzyme, therefore the reduction rate is not regulated by the metal free ion activity in solution. This is in direct contrast to previous measurements of trace metal interactions with the phytoplankton cell membrane. Half‐saturation constants for the reduction of Cu(II) complexes with carbonate, phenanthroline and bathocuproinedisulfonate are in the range 2.3–14.7 μM, which suggests that trace metal complexes are not the main electron acceptor in natural waters. In the diatom Thalassiosira weissflogii there is additional reductive activity associated with the cell wall.
TOTAL LIPID PRODUCTION OF THE GREEN ALGA NANNOCHLOROPSIS SP. QII UNDER DIFFERENT NITROGEN REGIMES1
Authors: Suen Yu , Hubbard J. S. , Holzer G. , Tornabene T. G. 
Published: April 2007

ABSTRACTThe green alga Nannochloropsis sp. QII was cultivated in media with sufficient and growth‐limiting levels of nitrogen (nitrate). Nitrogen deficiency promoted lipid synthesis yielding cells with lipids comprising 55% of the biomass. The major lipids were triacylglycerols (79%), polar lipids (9%) and hydrocarbons (2.5%). The polar lipids consisted of a broad range of phospholipids, glycolipids and sulfolipids. Other lipids identified were pigments, free fatty acids, saponifiable and unsaponifiable sterol derivatives, various glycerides, a family of alkyl‐1, 4‐dioxane derivatives and a series of alkyl‐ and hydroxyalkyl‐dimethyl‐acetals. Experiments in which 14CO2 was provided at different times in the growth cycle demonstrated that enhanced lipid biosynthesis at low nitrogen levels resulted principally from de novo CO2 fixation.
ULTRASTRUCTURE AND PIGMENTS OF TWO STRAINS OF THE PICOPLANKTONIC ALGAPELAGOCOCCUS SUBVIRIDIS(CHRYSOPHYCEAE)1
Authors: Vesk Maret , Jeffrey S. W. 
Published: April 2007

ABSTRACTThe organelle ultrastructure and photosynthetic pigments of a new isolate of the picoplanktonic alga Pelagococcus subviridis Norris from the East Australian Current was compared with the North Pacific Ocean type species. No differences in the ultrastructure of the two isolates were observed. Mitosis was studied in detail in the Australian strain, and showed two unusual features: the de novo appearance of centrioles prior to mitosis, and the formation of a small, extra‐nuclear spindle.The major carotenoids in both strains were fucoxanthin and a 19′‐butanoyloxyfucoxanthin‐like pigment, with diadinoxanthin and diatoxanthin as secondary pigments. Several minor carotenoids have not yet been identified. In addition to chlorophylls a and c2, a new chlorophyll c derivative (chlorophyll c3), present in both strains, was separated by high‐performance thin‐layer chromatography (HPTLC). The Australian isolate, unlike the type material, showed no evidence of chlorophyllase activity during cell harvest and extraction.While the pigment composition suggests affinities with certain newly examined prymnesiophytes, organelle ultrastructure indicates Pelagococcus to be a member of the Chrysophyceae. Mitosis is, however, atypical of both Prymnesiophyceae and Chrysophyceae, and if this picoplanktonic alga is to be retained in the Chrysophyceae it must be seen as a most unusual member.
DIURNAL PHOTOSYNTHETIC RESPONSES TO LIGHT BY MACROALGAE1,2
Authors: Coutinho Ricardo , Zingmark Richard 
Published: April 2007

ABSTRACTThe diurnal variability of photosynthesis vs. irradiance (P‐I) curves was evaluated for the six most dominant species of macroalgae that occur annually in North Inlet Estuary, South Carolina. Three existing models best simulated the observed data: (1) the Hyperbolic Tangent Model of Jassby and Platt (1976), which was applied to data that showed no photoinhibition; (2) the Exponential Inhibition Model of Parker (1974); and (3) the Photoinhibition Model of Platt et al. (1980), which were employed when photo‐inhibition was measured. Photoinhibition was observed in about 75% of the experiments, and in some cases at irradiance levels as low as 500 μE.m−2. s−1. Most of the resulting P‐I curves did not differ significantly when measured at various times of the day. As a consequence of these results, we question conclusions expressed by others that it is not possible to accurately determine diurnal photosynthesis of macroalgae from light saturation curves that are measured over short time periods.
STABLE DIPLOIDS FROM INTRAGROUP ZYGOSPORES OF CLOSTERIUM EHRENBERGII MENEGH. (CONJUGATOPHYCEAE)1
Authors: Kasai Fumie , Ichimura Terunobu 
Published: April 2007

ABSTRACTTwo pairs of stable diploid clones were obtained as aberrant forms among F1 progeny of an intragroup (intraspecific) cross between R‐11‐4 (mating type +) and M‐16‐4b (mating type ‐) of Group A of Closterium ehrenbergii Menegh. Each pair was derived from the two germination products of a single zygospore, and both clones were mating type minus. The cell size range of these four diploid minus clones was considerably above that of normal (haploid) Group A clones. Chromosome counts at the second meiotic metaphase indicated that these clones were diploid with approximately 200 chromosomes, which was double the number for normal Group A clones. Diploid minus clones conjugated normally with any haploid Group A plus clones, and yielded many triploid zygospores. Triploid zygospores germinated normally as did intragroup diploid zygospores. In metaphase I preparations, only bivalents were observed except on a few occasions where some uni‐ and multivalents were also detected. Viability of F1 progeny from triploid zygospores (55–74%) was somewhat lower than from diploid zygospores of Japanese Group A populations (65–90%), but higher than intergroup (interspecific) hybrid zygospores from Groups A, B and H (0–12%). In addition to lower viability, some F1 progeny from triploid zygospores exhibited slow vegetative growth. Almost all pairs of F1 clones from single triploid zygospores were of opposite mating type, similar to normal diploid zygospores of the intragroup cross. Morphological variability of F1 progeny of triploid zygospores was great. The apparently normal meiosis of triploid zygospores and the high viability of F1 progeny suggested that the genome of Group A contains several sets of chromosome complements with mechanisms by which bivalents are regularly formed in the first meiotic division.
A GREEN DINOFLAGELLATE WITH CHLOROPHYLLS a and b: MORPHOLOGY, FINE STRUCTURE OF THE CHLOROPLAST AND CHLOROPHYLL COMPOSITION1
Authors: Watanabe Makoto M. , Takeda Yoshie , Sasa Tsutomu , Inouye Isao , Suda Shoichiro , Sawaguchi Tomohiro , Chihara Mitsuo 
Published: April 2007

ABSTRACTA green‐colored marine unicell has been grown in unialgal culture and its morphology, chloroplast fine structure, and chlorophyll composition investigated. The organism is typical of dinoflagellates in its shape, flagellation, nucleus, mitochondria, and trichocysts. It is similar to Gymnodinium but possesses fine body scales. Chloroplasts and two kinds of vesicles bounded by double membranes, but no organelles obviously identifiable as nuclei or mitochondria, are associated in ribosome‐dense cytoplasm separated by a double membrane from the dinophycean cytoplasm. The chloroplasts are unlike any previously reported for dinoflagellates. Each is enclosed by an envelope consisting of a double membrane. Chloroplast lamellae consist of three appressed thylakoids. Interlamellar pyrenoids are present. Pigment analysis reveals chlorophylls a and b but not chlorophyll c. It seems likely that the organism is an undescribed dinoflagellate containing an endosymbiont with chlorophylls a and b and that the reduction of the endosymbiont nucleus and mitochondria has permitted a more initmate symbiosis.
MONOSPECIFIC AGGREGATIONS OF TWO CYANOPHYTES IN A EUTROPHIC LAKE1
Authors: Shapiro Joseph 
Published: April 2007

ABSTRACTMicrocystis incerta Lemmerman, and Lyngbya versicolor (Wartmann) Gomont, formed large monospecific aggregations on the surface of a lake rich in Aphanizomenon flos‐awuae (L.) Ralfs. Neither of the two algae in the aggregations was found in the water beneath.
The safety profile of automated collections: an analysis of more than 1 million collections
Authors: Wiltbank Thomas B. , Giordano Gerald F. 
Published: April 2007

BACKGROUND: Recent technology allows for the collection of 2‐unit red cells (RBCs) and single‐unit RBCs plus plasma or platelets (PLTs).STUDY DESIGN AND METHODS: With a common definition of adverse events, 1,023,682 whole‐blood collections were evaluated and compared with 249,154 two‐unit apheresis RBC collections, 40,870 single‐apheresis RBC collections, and 90,082 apheresis PLT collections.RESULTS: The data show that manual whole‐blood collections have a low incidence of moderate and severe reactions (47.1 per 10,000 collections, 0.47%). Single‐unit RBCs collected by apheresis have the same safety profile (37.44 per 10,000 collections, p > 0.20). Double‐RBC collections by apheresis and plateletpheresis have a significantly lower reaction rate (15.65 per 10,000 collections, p < 0.00005; and 14.84 per 10,000 collections, p < 0.00005, respectively).CONCLUSION: It is concluded that automated collections are safe or safer than manual whole‐blood collections. There should be few concerns when procedures are performed according to manufacturer's instructions.
Three missense mutations, including a novel 860C>T transition, and allelic enhancement phenomenon associated with ABO blood subgroups A in Taiwan
Authors: Li Lei , Yang Meng‐Hua , Chak Kin‐Fu , Lin Pi‐Hsiang , Lai Chao‐Hung , Lin Kuan‐Tsou , Tsai Su‐Jen Lin , Lin Kuo‐Sin , Chu Da‐Chang 
Published: April 2007

BACKGROUND: It was estimated that approximately 25 percent of Taiwanese residents were ABO blood group A. Many subgroups of A, however, revealed ambiguous serologic typing results. This study aimed to delineate the molecular basis of the A3, Ax, and weak A phenotypes.STUDY DESIGN AND METHODS: Serologic analyses including adsorption and elution assay, serum transferases activity assay, and saliva test were performed to determine the unique phenotypes of these samples. DNA sequencing and polymerase chain reaction–restriction fragment length polymorphism were performed to further investigate the relationships between the genetic characteristics and phenotypic features of these samples.RESULTS: Three single‐nucleotide transitions (745C>T, 820G>A, and a novel 860C>T) were found in nine A3/A3B cases. In addition, the Ax and A3B subjects shared the same 860C>T mutation. This Ax allele with 860C>T transition expressed A3B phenotype in Ax/B101 heterozygote but Ax phenotype in Ax/O01 heterozygote. This allelic enhancement was also observed in the weak A family with Aw05 allele, which was previously not found in Taiwan.CONCLUSION: This allelic enhancement phenomenon was prone to cause serologic discrepancy between parents and children. Genotyping could help us to resolve this problem. Thus, a novel mutation is reported among Taiwanese blood donors.
Storage of platelets in a novel additive solution (M‐sol), which is prepared by mixing solutions approved for clinical use that are not especially for platelet storage
Authors: Hirayama Junichi , Azuma Hiroshi , Fujihara Mitsuhiro , Homma Chihiro , Yamamoto Sadamitsu , Ikeda Hisami 
Published: April 2007

BACKGROUND: To reduce adverse reactions due to platelet (PLT) transfusion, medical solutions on the market, such as saline and ACD‐A, are used to replace the plasma of PLT concentrates in Japan; however, they are not strongly preservative. Here, an attempt was made to develop a novel additive solution (M‐sol) having the ability to preserve PLTs stably, with only approved solutions for clinical use.STUDY DESIGN AND METHODS: M‐sol is a mixture of solutions for medical use, which consists of 77 mmol per L NaCl, 3 mmol per L KCl, 1 mmol per L CaCl2, 21 mmol per L Na acetate, 15 mmol per L glucose, 9.4 mmol per L Na3 citrate, 4.8 mmol per L citric acid, 44 mmol per L NaHCO3, and 1.6 mmol per L MgSO4. The in vitro variables of PLTs stored in M‐sol, Seto‐sol, PASIIIM, or 100 percent plasma were compared during 14 days of storage.RESULTS: The in vitro parameters (pH, P‐selectin, %hypotonic shock response, %disk, mean PLT volume, aggregability) of PLTs were better maintained in M‐sol containing 3 percent plasma than in 100 percent plasma, PASIIIM with 31 percent plasma, and Seto‐sol with 3 percent plasma during 14 days of storage.CONCLUSION: The 2‐week storage of PLTs in M‐sol is feasible in terms of the in vitro PLT function. Our results here show that the additive solution, with a high ability to preserve PLTs, can be prepared by mixing solutions approved for clinical use that are not specifically for PLT storage.
Red blood cell (RBC) age at collection and storage influences RBC membrane‐associated carbohydrates and lectin binding
Authors: Sparrow Rosemary L. , Veale Margaret F. , Healey Geraldine , Payne Katherine A. 
Published: April 2007

BACKGROUND: Membrane‐associated carbohydrate changes act as signals for removal of senescent and damaged red blood cells (RBCs) from the circulation and could play a role in the RBC storage lesion and RBC survival after transfusion. In this study, a panel of lectins was used to investigate the expression of carbohydrates on RBCs that had been separated before storage into young and old RBCs.STUDY DESIGN AND METHODS: Leukodepleted RBCs were separated before storage into young and old RBCs (n = 9 paired units) by centrifugation and sampled at nominated time points during 42 days of storage. Changes to carbohydrate expression at the RBC membrane during storage were determined by flow cytometry with a panel of fluorescein‐labeled lectins.RESULTS: Old RBCs showed lower fluorescence intensity throughout storage, suggesting reduced binding of lectins compared to young RBCs. Progressively increased binding of lectins specific for galactose and N‐acetylglucosamine residues was observed during storage of young and old RBCs.CONCLUSION: Changes to lectin binding during storage of RBCs suggest that significant changes occur to the carbohydrate structures at the RBC membrane. These findings provide further insight into the mechanisms of the RBC storage lesion and potential influence on RBC survival after transfusion.
Choroidal neovascularization secondary to Sorsby fundus dystrophy treated with systemic bevacizumab (Avastin®)
Authors: Prager Franz , Michels Stephan , Geitzenauer Wolfgang , Schmidt‐Erfurth Ursula 
Published: April 2007

Abstract.Purpose:  A case of choroidal neovascularization (CNV) secondary to Sorsby fundus dystrophy (SFD) treated with systemic bevacizumab (Avastin®)Methods:  A 41‐year‐old woman presented with CNV secondary to SFD in her better eye. The patient received three initial infusions of bevacizumab at a dose of 5 mg/kg at 2 week intervals and one additional infusion because of CNV recurrence at the 7 month follow‐up.Results:  At 16 month follow‐up, visual acuity had improved from 20/50 at baseline to 20/25; optical coherence tomography and fluorescein angiography showed no evidence of CNV activity.Conclusion:  Systemic bevacizumab seems to be a promising treatment option for CNV secondary to SFD.
Aggregatibacter actinomycetemcomitans as indicator for aggressive periodontitis by two analysing strategies
Authors: Schacher Beate , Baron Frédéric , Roßberg Matthias , Wohlfeil Martin , Arndt Rita , Eickholz Peter 
Published: April 2007

AbstractObjective: To compare the subgingival microbiota of aggressive and chronic periodontitis (ChP) using single‐site and pooled plaque samples.Methods: In 60 patients with aggressive or ChP, subgingival plaque was sampled from the four deepest pockets using two sterile paper points simultaneously. One paper point from each pocket was put in a separate transport vial, the second was pooled with the three other paper points of a respective patient. The content of each vial was analysed for Aggregatibacter actinomycetemcomitans, Tannerella forsythensis, Porphyromonas gingivalis, and Treponema denticola.Results: Pooled plaque samples detected higher numbers for all tested pathogens than single‐site samples. Detection frequencies were similar for both strategies. Using single‐site samples, A. actinomycetemcomitans detection rate was statistically significantly a higher in aggressive than in ChP (p=0.01). A. actinomycetemcomitans was found in higher numbers, the other pathogens in lower numbers in aggressive than in ChP. Neither presence nor absence of one of the tested bacteria had sufficient positive or negative predictive value for aggressive periodontitis.Conclusion: A. actinomycetemcomitans was detected in higher numbers and frequency in aggressive than in ChP. Its detection may confirm the clinical diagnosis and influence therapy. As a diagnostic test, its sensitivity and predictive value was low.
Areca nut extracts‐activated secretion of leukotriene B4, and phosphorylation of p38 mitogen‐activated protein kinase and elevated intracellular calcium concentrations in human polymorphonuclear leukocytes
Authors: Hung S.‐L. , Lin Y.‐J. , Chien E. J. , Liu W.‐G. , Chang H.‐W. , Liu T.‐Y. , Chen Y.‐T. 
Published: April 2007

Background and Objective:  Polymorphonuclear leukocytes are the major source of leukotriene B4, which is synthesized via the 5‐lipoxygenase pathway. Activation of the 5‐lipoxygenase pathway is regulated by intracellular calcium and the phosphorylation of p38 mitogen‐activated protein kinase (MAPK). The impact of areca nut extracts on the biosynthesis of leukotriene B4 by human polymorphonuclear leukocytes was evaluated, and some of the possible mechanisms underlying the responses were examined.Material and Methods:  Polymorphonuclear leukocytes were treated with various concentrations of areca nut extracts. The concentrations of leukotriene B4 released into the supernatants were evaluated using enzyme immunoassay. The phosphorylation of p38 MAPK was monitored using immunoblotting, and the cytosolic calcium kinetics were assessed fluorometrically using Fura‐2.Results:  Exposure of polymorphonuclear leukocytes to areca nut extracts led to a dose‐dependent increase in the production of leukotriene B4, with levels peaking at 30 min and decreasing thereafter. Areca nut extracts enhanced the phosphorylation of p38 MAPK, an enzyme known to activate 5‐lipoxygenase. Incubation with areca nut extracts also resulted in a rapid elevation of intracellular calcium concentrations in polymorphonuclear leukocytes. The induction of leukotriene B4 by areca nut extracts was suppressed with the p38 MAPK inhibitor, SB203580, or with the intracellular calcium chelator, BAPTA‐AM.Conclusion:  The interaction of areca nut extracts with polymorphonuclear leukocytes activated the arachidonic acid metabolic cascade. Incubation of polymorphonuclear leukocytes with areca nut extracts resulted in the activation of intracellular events, such as phosphorylation of p38 MAPK and Ca2+ mobilization, involved in the release of pro‐inflammatory lipid mediators. The results of this study emphasize the potential importance of polymorphonuclear leukocytes as a source of leukotriene B4, which may modulate the inflammatory response in areca chewers.