bluuebunny/crossref_metadata_2025 huggingface dataset:
Adjuvant Ozonetherapy in Advanced Head and Neck Tumors: A Comparative Study
Authors: Clavo Bernardino , Ruiz Ana , Lloret Marta , López Laura , Suárez Gerardo , Macías David , Rodríguez Victor , Hernández Maria A. , Martín-Oliva Roberto , Quintero Santiago , Cuyás José M. , Robaina Francisco
Published: October 2004

Advanced head and neck (H&N) tumors have a poor prognosis, and this is worsened by the occurrence of hypoxia and ischemia in the tumors. Ozonetherapy has proved useful in the treatment of ischemic syndromes, and several studies have described a potential increase of oxygenation in tissues and tumors. The aim of this prospective study was to evaluate the clinical effect of ozonetherapy in patients with advanced H&N cancer in the course of their scheduled radiotherapy. Over a period of 3 years, 19 patients with advanced H&N tumors who were undergoing treatment in our department with non‐standard fractionated radiotherapy plus oral tegafur. A group of 12 patients was additionally treated with intravenous chemotherapy before and/or during radiotherapy. In the other group of seven patients, systemic ozonetherapy was administered twice weekly during radiotherapy. The ozonetherapy group was older (64 versus 54 years old, P = 0.006), with a higher percentage of lymph node involvement (71% versus 8%, P = 0.019) and with a trend to more unfavorable tumor stage (57% versus 8% IVb + IVc stages, P = 0.073). However, there was no significant difference in overall survival between the chemotherapy (median 6 months) and ozonetherapy (8 months) groups. Although these results have to be viewed with caution because of the limited number of patients, they suggest that ozonetherapy could have had some positive effect during the treatment of our patients with advanced H&N tumors. The adjuvant administration of ozonetherapy during the chemo–radiotherapy for these tumors merits further research.
Ozone Therapy on Cerebral Blood Flow: A Preliminary Report
Authors: Clavo Bernardino , Catalá Luis , Pérez Juan L. , Rodríguez Victor , Robaina Francisco
Published: October 2004

Ozone therapy is currently being used in the treatment of ischemic disorders, but the underlying mechanisms that result in successful treatment are not well known. This study assesses the effect of ozone therapy on the blood flow in the middle cerebral and common carotid arteries. Seven subjects were recruited for the therapy that was performed by transfusing ozone‐enriched autologous blood on 3 alternate days over 1 week. Blood flow quantification in the common carotid artery (n = 14) was performed using color Doppler. Systolic and diastolic velocities in the middle cerebral artery (n = 14) were estimated using transcranial Doppler. Ultrasound assessments were conducted at the following three time points: 1) basal (before ozone therapy), 2) after session #3 and 3) 1 week after session #3. The common carotid blood flow had increased by 75% in relation to the baseline after session #3 (P < 0.001) and by 29% 1 week later (P = 0.039). In the middle cerebral artery, the systolic velocity had increased by 22% after session #3 (P = 0.001) and by 15% 1 week later (P = 0.035), whereas the diastolic velocity had increased by 33% after session #3 (P < 0.001) and by 18% 1 week later (P = 0.023). This preliminary Doppler study supports the clinical experience of achieving improvement by using ozone therapy in peripheral ischemic syndromes. Its potential use as a complementary treatment in cerebral low perfusion syndromes merits further clinical evaluation.
Essential Oil of Betula pendula Roth. Buds
Authors: Demirci Betül , Paper Dietrich H. , Demirci Fatih , Can Başer K. Hüsnü , Franz Gerhard
Published: October 2004

The essential oil of Betula pendula Roth. buds was obtained using both hydrodistillation and microdistillation techniques and their chemical compositions were analyzed using both gas chromatography (GC) and gas chromatography–mass spectrometry (GC‐MS). Overall, more than 50 compounds were identified representing 80% and 92% for hydrodistillation and microdistillation, respectively. The main components (by hydrodistillation and microdistillation, respectively) found were α‐copaene (12% and 10%), germacrene D (11% and 18%) and δ‐cadinene (11% and 15%) in the analyzed essential oils. The microdistillation technique proved to be a useful tool and compliant alternative when compared to hydrodistillation.
Modulation of Immune Functions by Foods
Authors: Kaminogawa Shuichi , Nanno Masanobu
Published: October 2004

Evidence is rapidly accumulating as to the beneficial effects of foods. However, it is not always clear whether the information is based on data evaluated impartially in a scientific fashion. Human research into whether foods modulate immune functions in either intervention studies or randomized controlled trials can be classified into three categories according to the physical state of subjects enrolled for investigation: (i) studies examining the effect of foods in healthy individuals; (ii) studies analyzing the effect of foods on patients with hypersensitivity; and (iii) studies checking the effect of foods on immunocompromized subjects, including patients who had undergone surgical resection of cancer and newborns. The systematization of reported studies has made it reasonable to conclude that foods are able to modulate immune functions manifesting as either innate immunity (phagocytic activity, NK cell activity) or acquired immunity (T cell response, antibody production). Moreover, improvement of immune functions by foods can normalize the physical state of allergic patients or cancer patients, and may reduce the risk of diseases in healthy individuals. Therefore, it is valuable to assess the immune‐modulating abilities of foods by measuring at least one parameter of either innate or acquired immunity.
Design principles underlying circadian clocks
Authors: Rand D. A. , Shulgin B. V. , Salazar D. , Millar A. J.
Published: October 2004

A fundamental problem for regulatory networks is to understand the relation between form and function: to uncover the underlying design principles of the network. Circadian clocks present a particularly interesting instance, as recent work has shown that they have complex structures involving multiple interconnected feedback loops with both positive and negative feedback. While several authors have speculated on the reasons for this, a convincing explanation is still lacking.We analyse both the flexibility of clock networks and the relationships between various desirable properties such as robust entrainment, temperature compensation, and stability to environmental variations and parameter fluctuations. We use this to argue that the complexity provides the flexibility necessary to simultaneously attain multiple key properties of circadian clocks. As part of our analysis we show how to quantify the key evolutionary aims using infinitesimal response curves, a tool that we believe will be of general utility in the analysis of regulatory networks. Our results suggest that regulatory and signalling networks might be much less flexible and of lower dimension than their apparent complexity would suggest.
NMR and molecular dynamics studies of the interaction of melatonin with calmodulin
Authors: Turjanski Adrián G. , Estrin Darío A. , Rosenstein Ruth E. , McCormick John E. , Martin Stephen R. , Pastore Annalisa , Biekofsky Rodolfo R. , Martorana Vincenzo
Published: October 2004

Pineal hormone melatonin (N‐acetyl‐5‐methoxytryptamine) is thought to modulate the calcium/calmodulin signaling pathway either by changing intracellular Ca2+ concentration via activation of its G‐protein–coupled membrane receptors, or through a direct interaction with calmodulin (CaM). The present work studies the direct interaction of melatonin with intact calcium‐saturated CaM both experimentally, by fluorescence and nuclear magnetic resonance spectroscopies, and theoretically, by molecular dynamics simulations. The analysis of the experimental data shows that the interaction is calcium‐dependent. The affinity, as obtained from monitoring 15N and 1H chemical shift changes for a melatonin titration, is weak (in the millimolar range) and comparable for the N‐ and C‐terminal domains. Partial replacement of diamagnetic Ca2+ by paramagnetic Tb3+ allowed the measurement of interdomain NMR pseudocontact shifts and residual dipolar couplings, indicating that each domain movement in the complex is not correlated with the other one. Molecular dynamics simulations allow us to follow the dynamics of melatonin in the binding pocket of CaM. Overall, this study provides an example of how a combination of experimental and theoretical approaches can shed light on a weakly interacting system of biological and pharmacological significance.
Position dependence of the 13C chemical shifts of α‐helical model peptides. Fingerprint of the 20 naturally occurring amino acids
Authors: Vila Jorge A. , Baldoni Héctor A. , Scheraga Harold A.
Published: October 2004

The position dependence of the 13C chemical shifts was investigated at the density functional level for α‐helical model peptides represented by the sequence Ac‐(Ala)i‐X‐(Ala)j‐NH2, where X represents any of the 20 naturally occurring amino acids, with 0 ≤ i ≤ 8 and i + j = 8. Adoption of the locally dense basis approach for the quantum chemical calculations enabled us to reduce the length of the chemical‐shift calculations while maintaining good accuracy of the results. For the 20 naturally occurring amino acids in α‐helices, there is (1) significant variability of the computed 13C shielding as a function of both the guest residue (X) and the position along the sequence; for example, at the N terminus, the 13Cα and 13Cβ shieldings exhibit a uniform pattern of variation with respect to both the central or the C‐terminal positions; (2) good agreement between computed and observed 13Cα and 13Cβ chemical shifts in the interior of the helix, with correlation coefficients of 0.98 and 0.99, respectively; for 13Cα chemical shifts, computed in the middle of the helix, only five residues, namely Asn, Asp, Ser, Thr, and Leu, exhibit chemical shifts beyond the observed standard deviation; and (3) better agreement for four of these residues (Asn, Asp, Ser, and Thr) only for the computed values of the 13Cα chemical shifts at the N terminus. The results indicate that 13Cβ, but not 13Cβ, chemical shifts are sensitive enough to reflect the propensities of some amino acids for specific positions within an α‐helix, relative to the N and C termini of peptides and proteins.
EFFECTS OF SALINITY ON THE DISTRIBUTION OF CALOGLOSSA LEPRIEURII (RHODOPHYTA) IN THE BRISBANE RIVER, AUSTRALIA1
Authors: Mosisch Thorsten D.
Published: October 2004

The role of salinity as a factor determining the distribution of two red algal taxa, Caloglossa leprieurii (Mont.) J. Ag. var. leprieurii and Caloglossa leprieurii var. angusta Jao, along the course of the Brisbane River, Queensland, Australia, was investigated. In the field, C. leprieurii var. angusta tolerated a narrower salinity range (mean salinity = 0.0–18.9) than C. leprieurii var. leprieurii (mean salinity = 2.0–33.8) and occupied areas of lower salinity (salinity expressed according to the Practical Salinity Scale of 1978). Both taxa coexisted for a distance of 23 km along the middle reaches of the river. Cell measurements of specimens of both taxa collected along the river showed an increase in cell sizes upstream from the mouth. Results of a reciprocal transplant experiment and growth responses in a series of laboratory culture studies of the two taxa in a range of salinities are presented. These could be correlated with the field distribution of the algae, demonstrating their euryhalinity and the presence of distinct salinity ecotypes.
PRODUCTION OF HYALINE HAIRS BY INTERTIDAL SPECIES OF FUCUS (FUCALES) AND THEIR ROLE IN PHOSPHATE UPTAKE1
Authors: Hurd Catriona L. , Galvin Robert S. , Norton Trevor A. , Dring Matthew J.
Published: October 2004

A field study to determine the precise times of year at which three intertidal species of Fucus start to produce hyaline hairs and cease producing such hairs was conducted on the Isle of Man, U.K. Hairs were first observed during February, and within 6 days of their initial appearance, all tagged plants of all species at all tidal heights on the shore possessed hairs. Hair production continued until the beginning of October, at which time Fucus plants growing at the lowest stations (+ 3.0 m) had glabrous apical growth. Hair production continued later into the year for plants growing higher on the shore, and it was not until mid‐November that glabrous apical growth was observed in all plants.

Phosphate uptake rates of pilose (hairy) and glabrous (hairless) apical sections were measured in November 1988 for F. spiralis L. and in January 1989 for F. spiralis and F. serratus L., at phosphate concentrations ranging from 0.8 μM (ambient seawater) to 9.0 μM. In ambient seawater, pilose plants of F. spiralis removed phosphate 2–3 times faster than glabrous plants, whereas the uptake rates of pilose plants of F. serratus were about 50% greater than those of glabrous plants. The differences between uptake rates of pilose and glabrous plants of both species were smaller or nonsignificant at higher phosphate concentrations. The field and laboratory data are consistent with the hypothesis that hairs are formed in Fucus as a response to increased nutrient demand and that hairs facilitate the uptake of nutrients from seawater at concentrations typical of natural situations.
INHIBITORY EFFECTS OF CONCANAVALIN A AND TUNICAMYCIN ON SEXUAL ATTACHMENT OF ALEXANDRIUM CATENELLA (DINOPHYCEAE)1
Authors: Sawayama Shigeki , Sako Yoshihiko , Ishida Yuzaburo
Published: October 2004

The effect of concanavalin A (a lectin) and tunicamycin (an inhibitor of protein glycosylation) on sexual attachment of gamete pairs of the dinoflagellate Alexandrium catenella Whedon & Kofoid was studied. Concanavalin A inhibited sexual attachment at a concentration of 0.005%, and this inhibition was released by the addition of glucose or mannose at 10 mM. Mating type plus cells of A. catenella treated with tunicamycin for 12 h were not capable of sexual attachment. These results are the first to suggest the existence of a cell–cell recognition system in sexual attachment in A. catenella.
TWO DISTINCT SMALL‐SUBUNIT RIBOSOMAL RNA GENES IN THE NORTH AMERICAN TOXIC DINOFLAGELLATE ALEXANDRIUM FUNDYENSE (DINOPHYCEAE)1
Authors: Scholin Christopher A. , Anderson Donald M. , Sogin Mitchell L.
Published: October 2004

Two distinct small‐subunit ribosomal RNA genes, termed the A gene and B gene, were detected in a clonal isolate of the toxic dinoflagellate, Alexandrium fundyense Balech. The two sequences, which occur in roughly a 1:1 ratio in polymerase chain reaction‐amplified material, differ at approximately 40 positions scattered throughout the length of the molecule. Transcripts of the B sequence were not detected in total RNA extracts from nutrient‐replete and ammonium‐starved (sexually induced) cultures or nutrient‐replete log‐phase cultures harvested at 2‐h intervals over a complete circadian cycle. Many of the position changes in the B gene deviate from universally and eukaryotic‐conserved small‐subunit rRNA sequences. In contrast, the A gene is expressed under all culture conditions tested and does not violate any conserved sequence positions. Thus, the B sequence is not represented by stable transcripts and is likely a pseudogene. The B gene may serve as a useful marker for fine‐scale population and taxonomic analyses of some Alexandrium species.
THE CALCAREOUS RESTING CYST OF PENTAPHARSODINIUM TYRRHENICUM COMB. NOV. (DINOPHYCEAE)1
Authors: Montresor Marina , Zingone Adriana , Marino Donato
Published: October 2004

While investigating dinoflagellate cyst assemblages in surface sediments of the Gulfs of Naples and Salerno (Mediterranean Sea), we found a new calcareous resting cyst. This cyst has a round to oval body surrounded by a thick mineral layer, which gives it the shape of a Napoleon hat, with a flat, oval face bearing the archeopyle and a convex keel on the opposite side. The cyst shape is variable in both natural samples and clonal cultures. The organic membrane underlying the calcareous covering is resistant to acetolysis, thus demonstrating the presence of sporopolleninlike material. The cyst germinated into a motile stage having the same morphological features and thecal plate pattern as Peridinium tyrrhenicum Balech. We believe the validity of the genus Pentapharsodinium Indelicato & Loeblich should be accepted. Based on the comparative examination of the species we collected and of a similar species, Pentapharsodinium trachodium Indelicato & Loeblich, we propose Pentapharsodinium tyrrhenicum as a new combination for Peridinium tyrrhenicum.

The genus Pentapharsodinium also includes P. dalei Indelicato & Loeblich (= Peridinium faeroense Dale), which produces spiny, organic‐walled cysts. The presence of species forming calcareous cysts and species producing noncalcareous cysts in the same genus raises questions about maintaining the family Calciodinellaceae. This family should only include calcareous cyst‐forming peridinioids, in order to maintain a unified system of classification of fossil and recent dinoflagellates.
DISTRIBUTION AND SYSTEMATICS OF THE FRESHWATER GENUS SIRODOTIA(BATRACHOSPERMALES, RHODOPHYTA) IN NORTH AMERICA1
Authors: Necchi Orlando , Sheath Robert G. , Cole Kathleen M.
Published: October 2004

Multivariate morphometrics and image analysis were used to determine the number of well‐delineated infrageneric taxa of Sirodotia in North America. Three groupings were distinguished from 25 populations examined from Newfoundland and Quebec in the north to central Mexico in the south. These groupings were statistically related to 10 type specimens, and the following species were recognized: Sirodotia huillensis (Welwitsch ex W. et G. S. West) Skuja (syn. S. ateleia Skuja), S. suecica Kylin (syn. S. acuminata Skuja ex Flint and S. fennica Skuja), and S. tenuissima (Collins) Skuja ex Flint. These species are differentiated on the basis of whorl shape and degree of separation at maturity (S. suecica, rounded and appressed; S. huillensis and S. tenuissima, truncated apex and separated), the density of spermatangia (S. huillensis, dense clusters; S. suecica and S. tenuissima, sparsely aggregated), and the mode of germination of the gonimoblast initial (S. suecica and S. tenuissima, from the nonprotuberant side of the fertilized carpogonium; S. huillensis from the protuberant side). Sirodotia huillensis was found only in the desert‐chaparral, whereas S. suecica and S. tenuissima occurred from south‐temperate to boreal regions in cool (temperature 8–18° C), low ion (specific conductance 10–99 μS · cm−1), and mildly acidic to neutral (pH 5.7–7.3) waters.
GEL PURIFICATION OF RED ALGAL GENOMIC DNA: AN INEXPENSIVE AND RAPID METHOD FOR THE ISOLATION OF POLYMERASE CHAIN REACTION‐FRIENDLY DNA1
Authors: Saunders Gary W.
Published: October 2004

A simplified approach for the extraction of DNA from red algae in presented. Procedures are simple and fast, requiring a minimum of reagents and apparatus. The method involves an initial lysis step followed by an optional phenol/chloroform extraction. The final gel‐purification step removes polymerase chain reaction‐inhibiting polysaccharides from the DNA preparation. DNA is extracted as easily from dried algae as it is from snap‐frozen, fresh material, thus greatly facilitating the collection and transport of algal samples.
REGULATION OF ALTERNATIVE PATHWAY RESPIRATION IN CHLAMYDOMONAS REINHARDTH (CHLOROPHYCEAE)1
Authors: Weger Harold G. , Dasgupta Roshni
Published: October 2004

The inhibitor propyl gallate was used to estimate partitioning of respiratory electron flow between the cytochrome amd alternative pathways in Chlamydomonas reinhardtii Dangeard. Nutrient limitation (nitrogen or phosphorus resulted in a large increase in alternative pathway capacity relative to cytochrome pathway activity, without regulating in engagement of the alternative pathway. High rates of respiration, which could be induced in phosphate‐starved cells by a combination of phosphate addition and uncoupler, resulted in alternative pathway activity. Osmotic stress resulted in decreased electron flow through the cytochrome pathway and increased flow through the alternative pathway, while high temperature also resulted in alternative pathway engagement. Incubation with exogenous carbon sources could increase the rate of respiratory O2 consumption; the increase was mediated entirely by the alternative pathway. We suggest that the alternative pathway functions in these cells both to maintain respiration during environmentally induced stress and as on energy overflow.
CARBONIC ANHYDRASE IN THE CHLOROPLAST OF A COCCOLITHOPHORID (PRYMNESIOPHYCEAE)1
Authors: Quiroga Olivia , González Elma L.
Published: October 2004

The activity and subcellular distribution of carbonic anhydrase in a coccolithophorid alga, CCMP 299, was examined. The enzyme could not be detected in crude cell homogenates but was present at high specific activity (27.5 unit·mg−1 protein) in chloroplasts (density, 1.14 g·cm−3) isolated in a sucrose gradient. The carbonic anhydrase activity was sensitive to known inhibitors. Inhibition at 50% (I50) was obtained with concentrations of 4.60 mM and 2.65 mM for acetazolamide and NaN3, respectively. These levels are more consistent with patterns of inhibition previously observed for chloroplastic (as compared to periplasmic) carbonic anhydrase. In this organism, carbonic anhydrase was localized in the chloroplast stroma. These findings are discussed in terms of the relationship among dissolved inorganic carbon interconversions, photosynthesis, and calcification.
NUCLEAR BASIC PROTEINS FROM THE BINUCLEATE DINOFLAGELLATE PERIDINIUM FOLIACEUM (PYRROPHYTA)1
Authors: Morris Rodney L. , Fuller Christopher B. , Rizzo Peter J.
Published: October 2004

Histories of the endosymbiont nucleus of the binucleate dinoflagellate Peridinium foliaceum Stein were prepared from isolated nuclei and analyzed by peptide mapping, ammo acid composition, and two‐dimensional gel electrophoresis. Using these criteria, we identified the presence of two HI‐like histories and the core histones H3, H2A, H2B, and H4. These histones are similar but not identical to those of the endosymbiont nucleus of the bi‐nucleate dinoflagellate Peridinium balticum Levander.
STRUCTURE AND COTRANSCRIPTION OF THE PLASTID‐ENCODED rbcL. AND rbcS GENES OF PLEUROCHRYSIS CARTERAE (PRYMNESIOPHYTA)1
Authors: Fujiwara Shoko , Iwahashi Hitoshi , Someya Junichiro , Nishikawa Satoshi , Minaka Nobuhiro
Published: October 2004

Genes for the large (rbcL) and small (rbcS) subunits of ribulose‐1,5‐bisphosphate carboxylase/oxygenase (Rubisco) from the prymnesiophyte Pleurochrysis carterae (Braarud and Fagerl.) Christensen were isolated and characterized. The genes are located close to each other, separated by an intergenic region of 87 nucleotide base pairs. Southern and Northern blot analyses indicate that these genes are encoded by plastid DNA and cotranscribed, as in the Cryptophyta, Chromophyta, and Rhodophyta studied so far. The genes of Pleurochrysis show higher identities with those of the Cryptophyta, Chromophyta, Rhodophyta, and the α (Type I)‐ and β‐purple bacteria than with those of the Chlorophyta or Cyanophyta. The molecular Phylogenetic tree of rbcL genes suggests that the plastids of the Prymnesiophyta, Cryptophyta, and Chromophyta originated from those of the Rhodophyta, which agrees with the secondary endosymbiotic theory. Northern analysis of Pleurochrysis demonstrated that a certain amount of the transcript is possibly processed around the 3′ end rbcL. When cells were transferred from light to dark for 6 h, the amount of Rubisco messenger RNA (mRNA) was almost the same as in continuous light. This suggests that Rubisco mRNA is synthesized and/or stable even in the dark.
SURFACE MORPHOLOGY OF THE MARINE DINOFLAGELLATE SINOPHYSIS MICROCEPHALUS (DINOPHYCEAE) FROM A MANGROVE ISLAND. TWIN CAYS. BELIZE1
Authors: Faust Maria A.
Published: October 2004

Sinophysis microcephalus Nie and Wang 1944 is a nonphotosynthetic, tropical, benthic. dinophysoid dinoflagellate. I isolated it from floating detritus on a subtropical mangrove island. Twin Cays. Beleze, Central America, and describe its micromorphology from light and scanning electron micrographs. Cells of S. microcephalus are circular to subcircular and compressed laterally with a cell size of 42‐44 μm long and 33–35 μm wide and with a length /width ratio of 1.25–1.28. Areolae are numerous, 368–550 per valve, ranging in size from 0.75 to 2.0 μm. Pores are oblong and deeper at the valve's center and pentagonal‐shaped at the plate margin. The well‐defined cingulum is narrow and deeply incised with a smooth surface. The epitheca is small, moderately convex, and divided into two large, highly ornate, asymmetrical plate: the left and right epitheca I plates. The left epithecal plate bears two slightly curved, upright anterior projections located dorsally adjacent to the epithecal list, a relatively large opening, and three smaller openings compressed against the sagittal suture. The right plate contains a wide megacytic zone with two parallel ridges, a fairly large oblong opical pore in ventral position adjacent to the cingulum, and eight areolae each with a round, uniform‐sized pore opening. There are two long and narrow sulcal lists, gently convex with a smooth edge without structure or ribs. The left sulcal list has an ear‐shaped labe, a form of a primitive dinophysoid list. The megacytic zone is smooth and expands unevenly during cell division. The epitheca and sulcus distinguishes S. microcephalus from all examined Dinophysis.
GENOTYPIC VARIATION AND ALTERNATING DNA LEVELS AT CONSTANT CHROMOSOME NUMBERS IN THE LIFE HISTORY OF THE BROWN ALGA HAPLOSPORA GLOBOSA (TILOPTERIDALES)1
Authors: Kuhlenkamp Ralph , Müller Dieter G. , Whittick Alan
Published: October 2004

The brown algal order Tilopteridales contains three monospecific genera with reduced life histories, Which are assumed to have been derived form ancestors with oogamous reproduction and alternation of generations. The Newfoundland population of Haplospora globosa Kjellman still shows an alternation of gametophytes and sporophytes, but the chromosome Numbers remain equal because of parthenogenesis and apomeiosis, However, DNA fluorometry showed that the DNA level is twice as high in the Sporophytes as in the gametophytes, The DNA variation at constant chromosome numbers is presumably due to endomitosis combined with a law degree of polyteny. A genotypic variant of Haplospora is represented by the population at Helgoland (F.R.G.) where only sporophytes exist, Spores develop into sporophytes instead of gametophytes, and the plants have reduced chromosome number but the same DNA level as the Newfoundland sporophytes
PCR AMPLIFICATION OF NUCLEAR AND PLASTID GENES FROM ALGAL HERBARIUM SPECIMENS AND ALGAL SPORES1
Authors: Goff Lynda J. , Moon Debra A.
Published: October 2004

Plastid and nuclear ribosomal genes were amplified from an 11‐year‐old herbarium specimen using simple, rapid, nontoxic, and inexpensive methods. Gonimoblast tissue, isolated from either dried or fresh red algal cystocarps, was ground using the polyvalent, metal chelating resin Chelax 100. After boiling and centrifuging, the supernatant yielding enough DNA for 20 or more polymerase chain reactions. Using these methods, we also amplified plastid and nuclear genes from as few as two red algal spores. These methods should facilitate future studies of algal systematics, evolutionary biogeography, and phylogeny as well as studies of algal dispersal patterns and population biology.
COCCOLITH PRODUCTION AND DETACHMENT BY EMILIANIA HUXLEYI (PRYMNESIOPHYCEAE)1
Authors: Balch William M. , Kilpatrick Katherine , Holligan Patrick M. , Cucci Terry
Published: October 2004

Laboratory experiments were performed with the prymnesiophyte Emiliania huxleyi (Lohm.) Hay and Mohler, strain 88E, to quantify calcification per cell, coccolith detachment, and effects of coccolith production on optical scattering of individual cells. 14C incorporation into attached and detached coccoliths was measured using a bulk filtration technique. 14C‐labeled cells also were sorted using a flow cytometer and analyzed for carbon incorporation into attached coccoliths. The difference between the bulk and flow cytometer analyses provided a 14C‐based estimate of the rate of production of detached coccoliths. Coccolith production and detachment were separated in time in batch cultures, with most detachment happening well after calcification had stopped. Accumulation of coccoliths was maximum at the end of logarithmic growth with 50–80 coccoliths per cell (three to five complete layers of coccoliths around the cells). Net accretion rates of coccoliths were on the order of 7 coccoliths· cell−1·d−1 while net detachment rates were as high as 15 coccoliths· cell−1·d−1 for stationary phase cells. Equal numbers of coccoliths were attached and detached early in logarithmic growth, and as cells aged, the numbers of detached coccoliths exceeded the attached ones by a factor of 6. Our results demonstrate pronounced charges of forward angle light scatter and 90° light scatter of cells as they grow logarithmically and enter stationary phase. Counts of loose coccoliths in batch cultures are consistent with the detachment of coccoliths in layers rather than individual coccoliths.
DIATOM ASSEMBLAGES AS INDICATORS OF LAKE TROPHIC STATUS IN SOUTHEASTERN ONTARIO LAKES1
Authors: Christie Catherine E. , Smol John P.
Published: October 2004

Canonical correspondence analysis (CCA) was used to explore the relationship between measured environmental variables and surficial diatom (Bacillariophyceae) assemblages in alkaline lakes from southeastern Ontario. Total nitrogen (TN), watershed area, alkalinity, and maximum depth each explain significant (P ≤ 0.05) directions of variance in the distribution of diatom taxa.

TN was highly correlated to total phosphorus (TP) (r = 0.92), chlorophylla(r = 0.86), and Secchi depth (r =0.77). When a series of CCAs were run with the first axis constrained to each of these variables in turn, the ratio of the eigenvalue of the first axis to that of the second axis (λ1/λ2) was highest for TN, indicating that TN best explained the distribution of the diatom assemblages in this set of lakes. Furthermore, results of Monte Carlo permutation tests indicated that these four variables did not act independently on the diatom assemblages. Therefore, TN was selected to represent these four closely related variables to infer lake trophic status.

Weighted‐averaging regression and calibration (with classical deshrinking) were used to develop transfer functions to infer TN from the relative abundances of 83 diatom taxa recovered from the surficial sediments of 51 lakes. There was a good correlation between diatom‐inferred TN concentrations and measured TN concentrations (r2= 0.75, n = 51).

The weighted‐averaging regression and calibration model was used to infer lake trophic status (represented by TN) from diatom assemblages presented in the sediments from Little Round Lake, Ontario. These data were used in conjunction with historical land‐use data in order to quantify the sequence and extent of nutrient enrichment related to human activity in the watershed area.
A SEARCH FOR SOME ANG1OSPERM HORMONES AND THEIR METABOLITES IN CAULERPA PASPALOIDES (CHLOROPHYTA)1
Authors: Jacobs William P.
Published: October 2004

The best available methods were used to search for an‐giosperm hormones in the green alga Caulerpa paspa‐loides (Bory) Greville. Solvent partitioning of methanol extracts led to acidic ethyl acetate fractions that it were run through high‐performance liquid chromatography. Each of the resulting 25 fractions was divided in half so that one half was tested in the dwarf rice or lettuce hypocotyl assays for gibberellins and the other half was methylated and silylated for capillary gas chromatography combined with computerized mass spectrometry. By comparing algal mass spectra with spectra in the extensive library of mass spectra and associated Kovats Retention Indices that MacMillan's Bristol group has amassed, indole‐3‐acetic acid's presence in the alga was confirmed and dioxindole‐3‐acetic acid was found. However, despite the presence of several peaks of gibberellin‐like activity in the bioassays, no gibberellin or gibberellin metabolite was found in the thousands of full mass spectra examined. The gibberellin‐like activity in the acidic ethyl acetate fractions was therefore presumably not from any gibberellin known from vascular plants.
AUTO‐, HETERO‐, AND MIXOTROPHIC GROWTH OF CHLAMYDOMONAS HUMICOLA (CMLOROIMIYCKAK) ON ACETATE1
Authors: Lalibertè Gilles , de la Noüie Joël
Published: October 2004

Relative growth rate, isocitrate lyase activity, chlorophyll, protein, lipid, and soluble carbohydrate contents were investigated in Chlamydomonas humicola Lucksch during auto‐, mixo‐, and heterotrnphic growth. Mixotrophic cells have a relative growth rate of 1.66 d –1as compared to 0.78 d –1 and 0.21 d –1 for hetero‐ and autotrophic cells, respectively. Addition of acetate to autotrophic cells resulted in an increase in cell dry weight during the first day, followed by a rapid decrease and stabilization at 40 pg·cell –1. Cellular yield of mixotrophu cells, on a dry weight basis, was 6.6 times that of heterotrophic cells and 21.9 limes that of autotrophic ones. After 4 d, mixotrophic cells were characterized by higher chlorophyll (3.6% dry weight [d.w.]) and protein (58.6% d.w.) contents and lower lipid (4.8% d.w.) and soluble carbohydrate (1.3% d.w.) contents than those of autotrophic (2.6% d.w. chlorophyll, 31.0% d.w. protein, 10.2% d.w. lipid, and 6.5% d.w. soluble carbohydrate) and heterotrophic (1.5% d.w. chlorophyll, 36.9% d.w. protein, 5.6% d.w. lipid, and 6.0% d.w. soluble carbohydrate) cells. The ratio of chlorophyll a/b was highest in heterotrophic cells due to lower chlorophyll b content. Isocitrate lyase activity, a key enzyme in ecetate assimitation, could not be detected in autotrophic cells. Addition of 10 mM acetate to the culture medium of hetero‐ and mixotrophic cells resulted in increased isocitrate lyase activity with a maximum after 24 h, followed by a decline in activity over a 7‐d period. After 7 d of growth, only 0.01 mM acetate was found in the culture medium of mixotrophic cells as compared to 3.2 mM in the medium of heterotrophic ones, from an initial concentration of 10 mM.
ALTERATIONS IN LIPID MOLECULAR SPECIES OF THE MARINE EUSTIGMA TOPHYTE NANNOCHLOROSIS SP.1
Authors: Sukenik Assaf , Yamaguchi Yuji , Livne Alexander
Published: October 2004

The molecular species of triacylglycerol and monogalactosyl diacylglycerol from the marine eustigmatophyte Nannochloropsis were analyzed by high‐performance liquid chromatography with a flame ionization detector. Four major molecular species of triacylglycerol composed of C 14:0, C 16:0, and C 16:1 fatty acids at different combinations were identified. Six molecular species of monogalactosyl diacylglycerol were detected. Three of them contained C 20:5 fatty acid in the sn‐1 position, and one component accommodated C 20:5 fatty acid in both the sn‐1 and sn‐2 positions. Variations in the relative distribution of the molecular species were further monitored in Nannochloropsis cultures grown under different irradiance levels and temperatures. The relative distribution of 16: 0/16:1/16:0 triacylglycerol increased in cells grown in high light and in high temperature. Variations in cellular fatty acid composition in Nannochloropsis grown under different environmental conditions of irradiance level and temperature were attributed to alterations in relative cellular content of lipid classes as well as in the relative composition of lipid class molecular species.
THE CORTICAL MICROTUBULAR CYTOSKELETON OF OXYRRHIS MARINA (DINOPHYCEAE) OBSERVED WITH IMMUNOFLUORESCENCE AND ELECTRON MICROSCOPY1
Authors: Roberts Keith R. , Rusche M. Losoff , Taylor F. J. R.
Published: October 2004

The cortical microtubular cytoskeleton of Oxyrrhis marina Dujardin was investigated using indirect immunofluorescence and transmission electron microscopy. The cortical microtubular cytoskeleton is unlike that of other previously examined dinoflagellates because all cortical microtubules are oriented longitudinally and do not attach or abut tranverse microtubular arrays. This difference is considered along with other morphological and cytological variables as indicative of Oxyrrhis's phylogenetic position relative to the Dinophyceae.
MUCILAGE PROCESSING AND SECRETION IN THE GREEN ALGA CLOSTERIUM. II. ULTRASTRUCTURE AND IMMUNOCYTOCHEMISTRY1
Authors: Domozych David S. , Domozych Catherine Rogers
Published: October 2004

We conducted an ultrastructural and immunocytochemical analysis of the subcellular components involved in mucilage secretion in Closterium. In conventionally fixed cells, the mucilage vesicle appears dense‐cored with an electron‐dense center surrounded by radiating fibrils. In freeze‐substituted cells, the vesicles are highly osmiophilic. These mucilage vesicles are produced from peripheral swellings of the trans face cisternae of the Golgi apparatus (GA). The vesicles apparently move from the GA, found in cytoplasmic depressions between lobes of the plastid, to the sub‐plasma membrane peripheral cytoplasm. Here, they become associated with components of the peripheral cytoskeletal network. The mucilage is ultimately released through flask‐shaped pores in the cell wall.
STRUCTURE AND PHYSIOLOGY OF THE HAPTONEMA IN CHRYSOCHROMULINA (PRYMNESIOPHYCEAE). I. FINE STRUCTURE OF THE FLAGELLAR/HAPTONEMATAL ROOT SYSTEM IN C. ACANTHA AND C. SIMPLEX1
Authors: Gregson Andrew J. , Green J. C. , Leadbeater Barry S. C.
Published: October 2004

The intracellular structural relationships between the flagella and haptonema in Chrysochromulina acantha Leadbeater & Manton (Prymnesiophyceae) were studied in detail and a reconstruction is presented. Three micro‐tubular roots are associated with the flagellar apparatus. The largest, consisting of a sheet of approximately 20 microtubules, has its origins at the base of the left basal body. The main body of microtubules passes over the surface of a mitochondrion toward the left chloroplast and apparently terminates at a pair of microtubules oriented perpendicularly to it. Four microtubules diverge from the sheet and pass behind the left basal body. Two other roots–one consisting of a 2 + 2 + 1 arrangement of microtubules, the other of a single microtubule only—are associated with the right basal body. The two basal bodies are connected by distal and proximal fibers, and they are linked also to the base of the haptonema, three fibers extending from the haptonemal base to the right basal body, one only to the left. An additional fiber extending from the right basal body passes between the left basal body and the base of the haptonema, terminating at the largest microtubular root. Lateral extensions link this fiber to both the left basal body and the haptonematal base. Negative staining of isolated root systems of C. simplex Estep et al. shows that the arrangement of microtubules and fibrous connections is similar to that in C. acantha. The root system of C. acantha is compared to those of other members of the Prymnesiophyceae.
STRUCTURE AND PHYSIOLOGY OF THE HAPTONEMA IN CHRYSOCHROMULINA (PRYMNESIOPHYCEAE). II. MECHANISMS OF HAPTONEMATAL COILING AND THE REGENERATION PROCESS1
Authors: Gregson Andrew J. , Green J. C. , Leadbeater Barry S. C.
Published: October 2004

The axoneme in the free part of the haptonema in Chrysochromulina acantha Leadbeater & Manton and C. simplex Estep et al. consists of seven single microtubules, except in the extreme distal swelling where, in C. simplex, there are only three microtubules. In the extended haptonema, the microtubules are arranged in a ring though they are not evenly spaced, the gap between two of the microtubules being larger than that between any other neighboring pairs. In the coiled haptonema, rearrangement of the microtubules occurs so that the ring becomes distorted and the microtubules form two superposed arcs. A sliding microtubule mechanism is considered as a means by which haptonematal movement might be affected, and this is discussed in relation to the fine structure of both embedded material and negatively stained demembranated cells. We show that haptonematal coiling is dependent on the presence of calcium ions and that an external concentration of between 10−6 and 10−7 M Ca2+ is the threshold below which the frequency of coiling on cell death is reduced. The results of experiments using ethylene bis‐(oxyethylenenitrilo)‐tetracetic acid (EGTA) and lanthanum ions to control extracellular and intracellular Ca2+ concentrations are discussed in terms of both external free calcium and intracellular pools. We also show that haptonematal regeneration following excision begins with a short lag phase. This is followed by a period of rapid growth, decreasing after approximately 4 h. Full haptonematal regrowth is not achieved until after 12–15 h. The rate of haptonematal regeneration is strongly affected when the flagella are regenerating simultaneously. These observations are interpreted in terms of competition for intracellular precursors.
THE PHYCOBILISOME β18 SUBUNIT GENE OF ALLOPHYCOCYANIN IS LOCATED ON THE PLASTID GENOME IN AGLAOTHAMNION NEGLECTUM(RHODOPHYTA) AND CO TRANSCRIBED WITH AN UNIDENTIFIED OPEN READING FRAME1
Authors: Apt Kirk E. , Grossman Arthur R.
Published: October 2004

The gene encoding the β18 subunit of allophycocyanin (apcF) is on the plaqstid genome of the red alga Aglaothamnion neglectum Feldman‐Mazoyer. Immediately 31apcF and on the same transcript is a second open reading frame (ORF100) with homology (49% amino acid identity) to a gene tentatively identified as apcC in Cyanidium caldarium Geitler. The predicted amino acid sequence of the apcF gene product is 36% identical to analogous polypeptides from cyanobacteria. The apcF and ORF100 genes are clustered with other genes encoding phycobilisome polypeptides, which include the genes for the rod‐core linker polypeptide and the α and β subunits of phycoerythrin.
PHYSIOLOGICAL COMPARISON OF THE ISOMORPHIC LIFE HISTORY PHASES OF THE HIGH INTERTIDAL ALGA ENDOCLADIA MURICATA (RHODOPHYTA)1
Authors: Britting Susan A. , Chapman David J.
Published: October 2004

The isomorphic phases of Endocladia muricata (Post. & Rupr.) J. Ag. Were compared for photosynthetic and respiratory difference in response to a variety of environmental manipulations. Photosynthetic light response during submergence at 15° C and the pattern of respiratory recovery following prolonged emergence (3 h) at either 15° or 30° C were similar between gametophytes and tetrasporophytes. The phases showed the same ability to photosynthesize and respire during emergence at each temperature tested (15°, 25°, and 35° C, fully hydrated thalli) and at various desiccation state (measured at 25° C only). Submerged rates of photosynthesis following prolonged emergence at 15° and 30° C were, however slightly greater (17%) for tetrasporophytes as compared to gametophytes.

Regardless of the life history phase, plants incubated at 15° C during emergence recovered more completely than plants incubated at 30° C. Photosynthetic recovery after 1 h in plants incubated at 15° C often “spiked” and yielded rates as great as 185% of pretreatment rates. Increased photosynthetic rates during recovery were absent for the 30° C incubations. The initial photosynthetic recovery of plants collected from the upper limits of distribution was greater than that of plants collected from the lower limits. Recovered rates of respiration were highly variable over time. Respiration often exceeded pretreatment values more then threefold, and the elevated rates were sustained for 12 h. Photosynthesis and respiration in air were comparable to rates in seawater and varied slightly with increasing temperature. Photosynthetic and respiratory rates also decreased with increasing tissue water loss.

Thus, only slight differences in physiological performance were observed between phases and individuals collected from different vertical positions. Metabolic differences were transient and apparent only under experimental conditions that modeled extreme environmental conditions.
ANTARCTIC CYANOBACTERIA: LIGHT, NUTRIENTS, AND PHOTOSYNTHESIS IN THE MICROBIAL MAT ENVIRONMENT1
Authors: Vincent Warwick F. , Castenholz Richard W. , Downes Malcolm T. , Howard‐Williams Clive
Published: October 2004

The microenvironmental and photosynthetic characteristics of Antarctic microbial mats were measured in a series of ponds near McMurdo Sound. As elsewhere in Antarctica, these cold‐water benthic communities were dominated by oscillatoriacean cyanobacteria. Despite large variations in mat thickness, surface morphology, and color, all of the communities had a similar pigment organization, with a surface carotenoid‐rich layer that overlaid a deep chlorophyll maximum (DCM) enriched in phycocyanin as well as chlorophyll a. Spectroradiometric analyses showed that the DCM population inhabited an orange‐red shade environment. In several of the mats, the deep‐living trichomes migrated up to the surface of the mat within 2 h in response to a 10‐fold decrease in surface irradiance. The euphotic layer of the mats was supersaturated in oxygen and contained ammonium and dissolved reactive phosphorus concentrations in excess of 100 mg N·m−3 or P·m−3. Integral photosynthesis by core samples was saturated at low irradiances and varied two‐ to threefold throughout the continuous 24‐h radiation cycle. Oxygen microelectrode analyses showed that the photosynthetic rates were slow to negligible near the surface and maximal in the DCM. These compressed, nutrient‐rich euphotic zones have some properties analogous to planktonic systems, but the integrated photosynthetic responses of the community reflect the strong self‐shading within the mat and physiological dominance by the motile, DCM populations.
INDUCTION OF SPECIFIC PROTEINS IN EUKARYOTIC ALGAE GROWN UNDER IRON‐, PHOSPHORUS‐, OR NITROGEN‐DEFICIENT CONDITIONS1
Authors: La Roche Julie , Geider Richard J. , Graziano Lisa M. , Murray Helen , Lewis Kerith
Published: October 2004

What limits phytoplankton growth in nature? The answer is elusive because of methodological problems associated with bottle incubations and nutrient addition experiments. We are investigating the possibility that antibodies to proteins repressed by a specific nutrient can be used as probes to indicate which nutrient limits photosynthetic carbon fixation in the ocean. The diatom Phaeodactylum tricornutum Bohlin and the chlorophyte Dunaliella tertiolecta Butcher were grown in batch cultures in artificial seawater and f/2 nutrient lacking either phosphorus, iron, or nitrogen. Chlorosis was induced by nutrient limitation in both species with the exception of phosphorus‐limited D. tertiolecta. The synthesis and appearance of specific proteins were followed by labeling with 14C‐bicarbonate. Nutrient limitation in general leads to a decrease in the quantum efficiency of photosystem II, suggesting that deficiency of any nutrient affects the photosynthetic apparatus to some degree: however, the effect of nitrogen and iron limitation on quantum efficiency is more severe than that of phosphorus. A crude fractionation of the soluble and membrane proteins demonstrated that the large proteins induced under limitation by phosphorus and iron were associated with the membranes. However, small iron‐repressible proteins were located in the soluble fraction. Isolation with anion‐exchange chromatography and N‐terminal sequencing of iron‐repressible, 23‐kDa Proteins from D. tertiolecta, P. tricornutum, and Chaetoceros gracilis revealed that these small soluble proteins have strong homology with the N‐terminal sequence of flavodoxins from Azotobacter and Clostridium. The identity of the flavodoxin from D. tertiolecta was confirmed by immunodetection using antiflavodoxin raised against Chlorella. Flavodoxin was detected only under iron deprivation and was absent from nitrogen‐and phosphorus‐limited algae. Flavodoxin is a prime candidate for a molecular probe of iron limitation in the ocean. The requirements to confirm its utility in nature are discussed.