bluuebunny/crossref_metadata_2025 huggingface dataset:
ORIGINAL ARTICLE: Diversity and biogeography of the Antarctic flora
Authors: Peat Helen J. , Clarke Andrew , Convey Peter
Published: August 2006

Aim  To establish how well the terrestrial flora of the Antarctic has been sampled, how well the flora is known, and to determine the major patterns in diversity and biogeography.

Location  Antarctica south of 60° S, together with the South Sandwich Islands, but excluding South Georgia, Bouvetøya and the periantarctic islands.

Methods  Plant occurrence data were collated from herbarium specimens and literature records, and assembled into the Antarctic Plant Database. Distributional patterns were analysed using a geographic information system. Biogeographical patterns were determined with a variety of multivariate statistics.

Results  Plants have been recorded from throughout the Antarctic, including all latitudes between 60° S and 86° S. Species richness declines with latitude along the Antarctic Peninsula, but there was no evidence for a similar cline in Victoria Land and the Transantarctic mountains. Multi‐dimensional scaling ordinations showed that the species compositions of the South Orkney, South Shetland Islands and the north‐western Antarctic Peninsula are very similar to each other, as are the floras of different regions in continental Antarctica. They also suggest, however, that the eastern Antarctic Peninsula flora is more similar to the flora of the southern Antarctic Peninsula than to the continental flora (with which it has traditionally been linked). The South Sandwich Islands have a flora that is very dissimilar to that in all Antarctic regions, probably because of their isolation and volcanic nature.

Main conclusions  The Antarctic flora has been reasonably well sampled, but certain areas require further floristic surveys. Available data do, however, allow for a number of robust conclusions. A diversity gradient exists along the Antarctic Peninsula, with fewer species (but not fewer higher taxa) at higher latitudes. Multi‐dimensional scaling ordination suggests three major floral provinces within Antarctica: northern maritime, southern maritime, and continental. Patterns of endemism suggest that a proportion of the lichen flora may have an ancient vicariant distribution, while most bryophytes are more recent colonists.
Sublingual Tolerance Induction with Antigen Conjugated to Cholera Toxin B Subunit Induces Foxp3+CD25+CD4+ Regulatory T Cells and Suppresses Delayed‐Type Hypersensitivity Reactions
Authors: Sun J.‐B. , Cuburu N. , Blomquist M. , Li B.‐L. , Czerkinsky C. , Holmgren J.
Published: August 2006

Although sublingual (s.l.) immunotherapy with selected allergens is safe and often effective for treating patients with allergies, knowledge of the immunological mechanisms involved remains limited. Can s.l. administration of antigen (Ag) induce peripheral immunological tolerance and also suppress delayed‐type hypersensitivity (DTH) responses? To what extent can s.l.‐induced tolerance be explained by the generation of Foxp3+CD25+CD4+ regulatory T cells (Treg)? This study addressed these questions in mice and compared the relative efficacy of administering ovalbumin (OVA) conjugated to cholera toxin B (CTB) subunit with administration of the same Ag alone. We found that s.l. administration of a single or even more efficiently three repeated 40‐μg doses of OVA/CTB conjugate suppressed T‐cell proliferative responses to OVA by cervical lymph node (CLN), mesenteric lymph node (MLN) and spleen cells and concurrently strongly increased the frequency of Ag‐specific Treg in CLN, MLN and spleen and also transforming growth factor‐β (TGF‐β) levels in serum. The CLN and splenic cells from OVA/CTB‐treated BALB/c mice efficiently suppressed OVA‐specific T‐cell receptor (TCR) transgenic (DO11.10) CD25−CD4+ effector T‐cell proliferation in vitro. Further, s.l. treatment with OVA/CTB completely suppressed OVA‐specific DTH responses in vivo and T‐cell proliferative responses in mice immunized subcutaneously with OVA in Freund's complete adjuvant. The intracellular expression of Foxp3 was strongly increased in OVA‐specific (KJ1‐26+) CD4+ T cells from OVA/CTB‐treated mice. Thus, s.l. administration of CTB‐conjugated Ag can efficiently induce peripheral T‐cell tolerance associated with strong increases in serum TGF‐β levels and in Ag‐specific Foxp3+CD25+CD4+ Treg cells.
Sjögren's Syndrome‐Like Disease of C57BL/6.NOD‐Aec1 Aec2 Mice: Gender Differences in Keratoconjunctivitis Sicca Defined by a Cross‐Over in the Chromosome 3 Aec1 Locus
Authors: Nguyen C. , Singson E. , Kim J.‐Y. , Cornelius J. G. , Attia R. , Doyle M. E. , Bulosan M. , Cha S. , Peck A. B.
Published: August 2006

Sjögren's syndrome (SjS) is a systemic autoimmune disease in which an immunological attack primarily against the salivary and lacrimal glands results in loss of acinar cell tissue and function leading to stomatitis sicca and keratoconjunctivitis sicca. In recent years, the NOD mouse has become an accepted model of SjS, exhibiting a spontaneously developing disease that strongly mimics the human condition. Two genetic regions, one on chromosome 1 (designated Aec2) and the second on chromosome 3 (designated Aec1) of NOD mice, have been shown to be necessary and sufficient to recapitulate SjS‐like disease in non‐susceptible C57BL/6 mice. Here we describe a newly derived strain, C57BL/6.NOD‐Aec1R1Aec2, in which a recombination in Aec1 has resulted in reducing this genetic region to less than 20 cM from 48.5 cM. Profiling of this recombinant inbred strain has revealed that male mice maintain a full SjS‐like disease, whereas female mice exhibit stomatitis sicca in the absence of detectable keratoconjunctivitis sicca. These data suggest SjS‐like disease in the NOD mouse shows gender‐specific regulation determined by autosomal genes.
Nosocomial infection in an eye hospital: incidence and occurrence patterns
Authors: Wang Zhenfang , Hu Shuying , Jiang Yuzhen , Dong Nuo , Lin Xiaofeng , Yu Ayong
Published: August 2006

Abstract

Purpose:  To describe the incidence and occurrence patterns of nosocomial infections in a large eye hospital over a 6‐year period.

Methods:  Medical records of 94 013 consecutive inpatients admitted to Zhongshan Ophthalmic Centre, Guangzhou, China, from 1996 to 2002, were reviewed. Demographic data and infection diagnoses were collected. Nosocomial infection was defined as an infection that was absent during preadmission assessments but detected at least 48 h after admission to the hospital, or occurred after surgical procedures performed within the hospital.

Results:  The cumulative incidence of nosocomial infections over a 6‐year period was 0.28%. The most common infections were acute conjunctivitis (45.5%) and upper respiratory tract infection (36.4%), followed by suppurative endophthalmitis (8.3%). Patients with acute conjunctivitis were predominantly adults aged from 15 to 59 years (60%), while patients with upper respiratory tract infection were predominantly children of 14 years or younger (74.0%), and those with endophthalmitis predominantly older persons 60 years or older (68.2%). Conditional pathogenic bacteria, mainly gram‐positive, were responsible for most suppurative endophthalmitis cases.

Conclusions:  Although nosocomial infection incidence is relatively low in this eye hospital, our data suggest that different subgroups of patients are prone to certain types of infection. Specific preventive strategies targeting different subgroups of inpatients may further reduce the infection incidence.
Immediate postoperative intraocular pressure measurements after trabeculectomy with releasable sutures
Authors: Mehta Jodhbir S , Maurino Vincenzo , Patel Hemankumar , Kirwin James , Murdoch Ian E
Published: August 2006

Abstract

Background:  To assess the practicality of same‐day intraocular pressure (IOP) review following trabeculectomy with releasable sutures. It is a prospective observational case series study.

Methods:  40 eyes of patients undergoing inpatient trabeculectomy for glaucoma optic neuropathy. IOP measurement at 2, 4, 8, 12 and 24 h following trabeculectomy with releasable sutures. Slit‐lamp microscopy documenting surgical complications.

Results:  Three patients required intervention within the first 24 h and four patients at 24 h because of raised IOP. Investigating pressure outcomes of low (<8 mmHg) and high (>21 mmHg) the sensitivity and specificity of IOP assessments at 2, 4, 8 and 12 h were compared with a ‘gold standard’ of IOP at 24 h postoperatively. False negative results persist at time periods for low IOP and are absent for high IOP only at 8 h postoperatively. There is a marked change in IOP over the first 24‐h period in some patients, both from high to low and from low to high levels.

Conclusions:  Same‐day review of trabeculectomy is not a practical proposition as a policy for a unit with present operative techniques. Indeed the finding of transient high pressures during the first 24 h in some cases suggests that in those patients for whom there is concern (mainly those with severe disc cupping at the time of surgery) at least one IOP check during the first 24 h postoperatively may be warranted in addition to the 24‐h postoperative check.
Role of mammalian sperm nuclear structure in fertilization and embryo development
Authors: KATAYOSE HARUO , TAKAYAMA TOMOKO , HAYASHI SHOUTAROU , SATO AKIRA
Published: August 2006

Although intact spermatozoon is successfully collected from infertile patients, repeated implantation failure or pregnancy loss are often experienced. Sperm nuclear defects have been thought to be one of the most important reasons for repeated assisted reproductive technology failure. In comparison with other mammalians, characteristic heterogeneity has been found in each mature human sperm nuclei, therefore it is necessary to investigate the significance between fertilization failure, developmental disability and structural abnormality of human sperm nuclei. Furthermore, if close relationships between the heterogeneity of human ejaculated sperm nuclei and DNA fragmentation are defined by analyzing sperm nucleoproteins, it would be clearly shown that impaired sperm chromatin leads to failure of embryo developmentin vitroorin vivo, so called late paternal effect on embryo development. It will be necessary in the near future to study the strategy for more novel methodology than those previously reported in terms of sperm selection. The present report reviews the roles of mammalian sperm nuclear structure, especially in humans, in fertilization and embryo development after the insemination procedure. (Reprod Med Biol 2006;5: 161–168)
Role of oocyte‐specific genes in the development of mammalian embryos
Authors: MINAMI NAOJIRO , TSUKAMOTO SATOSHI
Published: August 2006

Studies on oocyte‐specific genes are important in understanding the genetic pathways essential for folliculogenesis, oogenesis and early embryogenesis. Although the molecular mechanisms regulating oocyte growth and embryo development in mammals have partially been unraveled by gene knockout studies, many aspects concerning reproduction remain to be determined. Development of mammalian embryos starts with the fusion of sperm and egg. After fertilization, the first major developmental transition, maternal to zygotic transition, occurs at the specific stages of preimplantation development in each mammal. The transition is called zygotic gene activation (ZGA) or embryonic genome activation. The ZGA is one of the most important events that occur during preimplantation development; however, the mechanism of the event remains unknown. Because the development until the transition is maintained by maternally inherited proteins and transcripts stored in the oocytes, it is highly likely that these products play an important role in the initiation of ZGA. Several maternal‐effects genes that are specifically expressed in oocytes have been identified and their involvement in preimplantation development has been revealed. Therefore, to study oocyte‐specific gene regulation would help not only to understand the precise mechanisms of mammalian development, but also to show the mechanisms of reproductive disorders, such as premature ovarian failure and infertility. (Reprod Med Biol 2006; 5: 175–182)
Comparative study of Sperm Motility Analysis System and conventional microscopic semen analysis
Authors: KOMORI KAZUHIKO , TSUJIMURA AKIRA , ISHIJIMA SUMIO , TANJAPATKUL PHANU , FUJITA KAZUTOSHI , MATSUOKA YASUHIRO , TAKAO TETSUYA , MIYAGAWA YASUSHI , TAKADA SHINGO , OKUYAMA AKIHIKO
Published: August 2006

Background and Aim:  Conventional manual sperm analysis still shows variations in structure, process and outcome although World Health Organization (WHO) guidelines present an appropriate method for sperm analysis. In the present study a new system for sperm analysis, Sperm Motility Analysis System (SMAS), was compared with manual semen analysis based on WHO guidelines.

Materials and methods:  Samples from 30 infertility patients and 21 healthy volunteers were subjected to manual microscopic analysis and SMAS analysis, simultaneously. We compared these two methods with respect to sperm concentration and percent motility.

Results:  Sperm concentrations obtained by SMAS (Csmas) and manual microscopic analyses on WHO guidelines (Cwho) were strongly correlated (Cwho = 1.325 × Csmas; r = 0.95, P < 0.001). If we excluded subjects with Csmas values >30 × 106 sperm/mL, the results were more similar (Cwho = 1.022 × Csmas; r = 0.81, P < 0.001). Percent motility obtained by SMAS (Msmas) and manual analysis on WHO guidelines (Mwho) were strongly correlated (Mwho = 1.214 × Msmas; r = 0.89, P < 0.001).

Conclusions:  The data indicate that the results of SMAS and those of manual microscopic sperm analyses based on WHO guidelines are strongly correlated. SMAS is therefore a promising system for sperm analysis. (Reprod Med Biol 2006; 5: 195–200)
Crack growth predictions in a complex helicopter component under spectrum loading
Authors: NEWMAN J. C. , IRVING P. E. , LIN J. , LE D. D.
Published: August 2006

Fatigue crack growth predictions have been made on a helicopter round‐robin crack configuration. The crack configuration was a small corner defect at the edge of a large central hole in a flanged plate made of 7010 aluminium alloy and the component was subjected to a simulated helicopter spectrum loading. The crack growth rate data and the stress‐intensity factor (K) solution for the crack configuration were provided in the round‐robin. The FASTRAN life‐prediction code was used to predict fatigue crack growth under various load histories on the aluminium alloy, such as Rotorix and Asterix, on both compact tension C(T) specimens and the complex crack configuration. A BEASY three‐dimensional stress‐intensity factor solution for the round‐robin problem was also provided for this paper and is compared with the original K solution. Comparisons are made between measured and predicted fatigue crack growth lives for both crack configurations. The predicted lives for the C(T) specimens were 15–30% longer than the measured lives; and crack growth in the round‐robin configuration agreed very well in the early stages of crack growth, but the life was 30% short of the test results at the final crack length.
Bowel hematoma following an iliohypogastric‐ilioinguinal nerve block
Authors: FRIGON CHANTAL , MAI RYAN , VALOIS‐GOMEZ TERESA , DESPARMET JOËLLE
Published: August 2006

We report a case of a subserosal small bowel hematoma following an ilioinguinal‐iliohypogastric nerve block for an appendicectomy in a 6‐year‐old girl. The bowel hematoma was noted in the wall of the terminal ileum after opening the peritoneum. The hematoma was nonobstructing and the child remained asymptomatic. We discuss the technical aspects of this block.
Consumer identity and moral obligations in non‐plastic bag consumption: a dialectical perspective
Authors: Cherrier Hélène
Published: August 2006

According to many, we live in an era of autonomy, choice, enterprise and lifestyles. Consumers are active agents who exercise informed and autonomous responsibilities in relation to their values and concerns. This language shows the act of ethical consumption as a personal choice arising from individual concerns. In contrast to this liberal view, the conservatives claim that consumers need to obey prescriptive and proscriptive set of ethical norms in order to consume ethically. This study takes on a third approach and considers consumers both as subjects of moral obligations (the conservative view) and as actors of their life (the liberal view). The analysis of nine existential phenomenological interviews performed on consumers who use environmentally friendly bags for their grocery shopping shows how both liberal and conservative views are co‐productive in the development of ethical consumerism. The dialectical interplay between social norms and self‐identity evolves through time and context across ﬁve main components: community of meaning and support, emotional afﬁliation, localized access to political discourses, personalization of the practice and identity formation. All ﬁve elements are intertwined around the use of a symbolic possession at the level of local and mundane microsocial encounters.
STRATEGIES AND KINETICS OF PHOTOACCLIMATION IN THREE ANTARCTIC NANOPHYTOFLAGELLATES1
Authors: Buma Anita G. J. , Noordeloos Anja A. M. , Larsen Jacob
Published: August 2006

Three Antarctic nanophytoflagellates (two cryptophyte species and a Pyramimonas sp.) were compared for their capacity to phiotoacclimate and for their kinetic responses in changing photic environments. Division rate, cell size cellular fluorescence, and chlorophyll a content were measured steady and transient states of semi‐continuous cultures maintain at 1.0° C. Of all parameters tested, cell size was most affected by irradiance. Acclimation kinetics were modeled using a first‐order equation. Rates of change in cell size following shifts in irradiance were comparable with rates of change in chemical composition reported for temperate algae. Response rates of cellular in vivo red and orange fluorescence were lower. In many cases, however, responses could not be described by the first‐order kinetic model. Division rates remained high for approximately 3 days following a shift down in irradiance, after which new division rates were established. The nanoflagellates studied here appear to respond to small irradiance perturbations at low rates. However, they may fail to adapt and abrupt changes in photon flux density (PFD). When shade‐adapted (25 μmol, m−2, m−2, s−1) cells were exposed to high PFD (400 μmol, m−2, s−1) for 1–3 days, cell were incapable of readapting division rate and pigment content to the initial irradiance condition (25 μmol, m−2, s−1) for about 1 month following the shift‐down step. The ecological role of the kinetics of photoacclimation in nanophytoflagellate growth performance in Antarctic ecosystems is discussed.
EVIDENCE A PHOTOPROTECTIVE FOR SECONDARY CAROTENOIDS OF SNOW ALGAE1
Authors: Bidigare Robert. R. , Ondrusek Michael E. , Kennicutt Mahlon C. , Iturriaga Rodolfo , Harvey H. Rodger , Hoham Ronald W. , Macko Stephen. A.
Published: August 2006

Snow algae occupy a unique habitat in high altitude and polar environments. These algae are often subject to extremes in nutrient availability, acidity, solar irradiance, desiccation, and ambient temperature. This report documents the accumulation of secondary carotenoids by snow algae in response to the availability of nitrogenous nutrients. Unusually large accumulations of astaxanthin esters in extra‐chloroplastic lipid globules produce the characteristics red pigmentation typical of some snow algae (e.g. Chlamydomonas nivalis (Bauer) Wille). Consequently these compounds greatly reduce the amount of light available for absorption by the light‐harvesting pigment‐protein complexes, thus potentially limiting photoinhibition and photodamage caused by intense solar radiation. The esterification of astaxnthin with fatty acids represents a possible mechanism by which this chromophore can be concentrated within cytoplasmic globules to maximize its photoprotective efficiency.
THE FINE STRUCTURE AND SCALE FORMATION OF CHRYSOLEPIDOMONAS DENDROLEPIDOTA GEN. ET. SP. NOV.(CHRYSOLEPIDOMONADACEAE FAM. NOV., CHRYSOPHYCEAE)1
Authors: Peters Michael C. , Andresen Robert A.
Published: August 2006

Chrysolepidomonas gen. nov. is described for single‐celled monads with two flagella, a single chloroplast, and distinctive canistrate and dendritic scales. The type species, Chrysolepidomonas dendrolepidota sp. nov., is described for the first time. The canistrate scales bear eight “bumps” on the top surface, and the dendriticscales have a tapered base with a quatrifid tip. These organic scales are formed in the Golgi apparatus and storred in a scale reservoir. The scale reservoir is bounded on two sides by the R1 and R2 in microtubular roots of the basal apparatus. The cyst (=stomatocyst, statospore) forms endogenously by means of a silica deposition vesicle. The outer cyst surface is smooth, and the pore region is unornamented. Two other organisms bearing canistrate and dendritic scales, previously assigned to the genus Sphaleromants, are transferred to the genus Chrysolepidomonas. They are C.angalica sp. nov. and C. marine(Pienaar) comb. nov. The distinguishing features of Chrysolepidomonas and Sphaleromantis are discussed. A new family, Chrysolepidomonadceae fam. noc., is described for flagellates covered with organic scales.
RHYTHMIC SETTLING BEHAVIOR IN PYRAMIMONAS PARKEAE (PRASINOPHYCEAE)1
Authors: Griffin Neil J. , Aken Mark E.
Published: August 2006

Pyramimonas parkeae Norris et Pearson was examined for evidence of a settling rhythm while growing in laboratory culture. The alga settled rhythmically in a diet cycle when kept in a regularly alternating light‐dark cycle. Cells moved out of suspension when settling and attached themselves to the sides and base of the culture vessel. Although rhythmic settling was inhibited in constant dim light (LL), it continued in constant darkness for 4 days with a period of approximately 24 h. The settling rhythm was temperature‐compensated and could be reset by 6‐h exposures to light. These observations demonstrate that the settling behavior of P. parkeae is controlled by an endogenous circadian oscillator. Regular low temperature pulses every 12 h removed the inhibition caused by LL and this points to the possible role of temperature changes as stimuli entraining the circadian settling rhythm of P. parkeae.
MACROMOLECULES EXUDED BY SYMBIOTIC DINOFLAGELLATES IN CULTURE: AMINO ACID AND SUGAR COMPOSITION1
Authors: Markell Douglas A. , Trench Robert K.
Published: August 2006

Five species of symbiotic dinoflagellates in culture exude water‐soluble glycoconjugates. Recovered glycoconjugates of three of the five species were composed of more carbohydrate than protein. The uronic acid content of three algal species that infect scyphistomae of the jellyfish Cassiopeia were higher than those of the two species that do not infect. Analyses of hydrolysates by high‐performance liquid chromatography indicated that the protein components were rich in aspartic acid (asparagine), glutamic acid (glutamine), serine, glycine, leucine, and threonine and contain proline and lysine. Histidine and methionine, when present, were in low concentration. Other sugars detected were glucose and galactose and their respective amines, ribose, mannose, and fucose. Neither sialic acid nor arabinose was detected. The release of glycoconjugates by symbiotic dinoflagellates appears to be a general phenomenon. Some components of these macromolecules could serve as signals that pass between symbionts and hosts, while other components, assuming host digestion, could be a source of previously undetected essential amino acids.
BLUE LIGHT PHOTOREACTIVATION IN ULTRAVIOLET‐IRRADIATED YOUNG SPOROPHYTES OF ALARIA ESCULENTA AND LAMINARIA SACCHARINA (PHAEOPHYTA)1
Authors: Han Taejun , Kain (Jones) Joanna M.
Published: August 2006

Exposure of ultraviolet (UV)‐irradiated young sporophytes of Alaria esculenta (L.) Grev. and Laminaria saccharina (L.) Lamour. to visible light resulted in recovery from UV damage that would otherwise cause much higher mortality. For this photoreactivation, blue light was highly effective, whereas negligible reactivation was produced in green or red light. The blue quantum requirements for a 50% response were 1.9 mol·m−2 in A. esculenta and 1.2 mol·m−2 in L. saccharina, which were comparable to those reported for other blue light responses requiring high energy found in brown algae.
DISTRIBUTION AND SYSTEMATICS OF FRESHWATER CERAMIALES (RHODOPHYTA) IN NORTH AMERICA1
Authors: Sheath Robert G. , Vis Morgan L. , Cole Kathleen M.
Published: August 2006

Twenty‐five freshwater populations of Ceramiales were collected in North America, 24 of which were from the tropical rainforest region of Central America and the Caribbean. The streams tended to be moderate in mean current velocity (X̄= 23.3 cm·S−1) and maximum width (X̄= 6.3 m) but high in temperature (X̄= 23.1°C), pH (X̄= 7.9), and specific conductance (X̄= 320 μS·cm−1). Three Bostrychia species were restricted to the Caribbean islands: B. moritziana (Sonder ex Kütz.) J. Ag. (syn. B. cornigera Mont. and B. radicans f. moliforme Post), with ecorticate indeterminate axes, monosiphonous ultimate branches, and cladohaptera; B. radicans (Mont.) Mont. (syn. B. leprieurii Mont and B. rivularis Harv.), with ecorticate and polysiphonous axes throughout and cladophaptera; and B. tenella (Lamour.) J. Ag., with corticate indeterminate axes, monosiphonous ultimate branches, and peripherohaptera. Ballia prieurii Kütz. was found in Belize and Costa Rica and was characterized by rebranched determinate laterals, opposite branching, and long apical cells (X̄= 61 μm) and axial cells (X̄= 43 μm). Caloglossa leprieurii (Mont.) J. Ag. was localized in Puerto Rico while. C. ogasawaerensis Okam. was collected only in Costa Rica. The two species were separated by site of branching (midrib vs. margin) and blade width (X̄= 384 vs. 861 μm). Polysiphonia subtilissima Mont. from Florida and Jamaica had four pericentral cells, no cortication, rhizoids arising from pericentral cells, and branches initiated at trichoblast scars.
PHYSIOLOGICAL RESPONSES TO TEMPERATURE AND IRRADIANCE IN SPIROGYRA (ZYGNEMATALES, CHAROPHYCEAE)1
Authors: Graham James M. , Lembi Carole A. , Adrian Holly L. , Spencer David F.
Published: August 2006

Spirogyra Link (1820) is an anabranched filamentous green alga that forms free‐floating mats in shallow waters. It occurs widely in static waters such as ponds and ditches, sheltered littoral areas of lakes, and stow‐flowing streams. Field observations of its seasonal distribution suggest that the 70‐μm‐wide filament form of Spirogyra should have a cool temperature and high irradiance optimum for net photosynthesis. Measurements of net photosynthesis and respiration were marie at 58 combinations of tight and temperature in a controlled environment facility. Optimum conditions were 25°C and 1500 μmol photons m−2 s−1, at which net photosynthesis averaged 75.7 mg O2 gdm−1 h−1. Net photosynthesis was positive at temperatures from 5° to 35°C at most irradiances except at combinations of extremely low irradiances and high temperatures (7 and 23 μmol photons m−2 s−1 at 30°C and 7, 23, and 35 μmol photons m−2 s−1 at 35°C). Respiration rates increased with both temperature and prior irradiance. Light‐enhanced respiration rates were significantly greater than dark respiration rates following irradiances of 750 μmol photons m−2 s−1 or greater. Polynomials were fitted to the data to generate response surfaces; such response surfaces can be used to represent net photosynthesis and respiration in ecological models. The data indicate that the alga can tolerate the cool water and high irradiances characteristic of early spring but cannot maintain positive net photosynthesis under conditions of high temperature and low light (e.g. when exposed to self‐shading).
PIGMENTS OF BATHYCOCCUS PRASINOS (PRASINOPHYCEAE): METHODOLOGICAL AND CHEMOSYSTEMATIC IMPLICATIONS1,2
Authors: Egeland Einar Skarstad , Johnsen Geir , Eikrem Wenche , Throndsen Jahn , Liaaen‐Jensen Synnøve
Published: August 2006

Bathycoccus prasinos Eikrem et Throndsen exhibited a complex carotenoid distribution pattern including the carotenes β,β‐carotene (0.8% of total carotenoids) and β, ° Carotene (0.4%) and several xanthophylls. These were prasinoxanthin (49% of total carotenoids), micromonal (16%), neoxanthin (14%), uriolide (7%), violaxanthin (0.8%), 31‐dehydrouriolide (0.8%), dihydrolutein (0.1%), two partly characterized esterified carotenols (together 10%), and five minor unidentified carotenols (together 2%). The identifications were based on high‐performance liquid chromatography (HPLC), thin‐layer chromatography (TLC), visible spectroscopy (VIS), and mass spectra (MS) and in part on 1H nuclear magnetic resonance (NMR), circular dichroism (CD), and chemical derivatization. The carotenoid composition of B. prasinos was related to that of other prasinoxanthin / uriolide / micromonal‐producing prasinophytes (Mantoniella squamata, Micromonas pusilla, and Pseudoscourfieldia marina). The relative distribution of chlorophylls (w/w) were chlorophyll a (chl a; 63%), chl b (31%), and an unknown chl c‐like chlorophyll (7%) with spectral characteristics similar to magnesium 2,4‐divinylphaeoporphyrin a, monomethyl ester, compatible with other prasinophytes. The chemosystematic data and ultrastructural characteristics for the order Mamiellales are discussed. We conclude that HPLC studies alone are insufficient for the identification and characterization of the carotenoids, including the minor carotenoids essential for biosynthetic/chemosystematic considerations.
ISOLATION, PURIFICATION, AND CHARACTERIZATION OF DMSP LYASE (DIMETHYLPROPIOTHETIN DETHIOMETHYLASE (4.4.1.3)) FROM THE RED ALGA POLYSIPHONIA PANICULATA1
Authors: Nishiguchi Michele K. , Goff Lynda J.
Published: August 2006

Polysiphonia paniculata Montagne is an intertidal red alga known to produce large amounts of the compound dimethylsulfoniopropionate (DMSP). Conversion of this substrate into dimethylsulfide is accomplished in P, paniculata by an enzyme called DMSP lyase (dimethylpropiothetin dethiomethyla.se (4.4.1.3)). DMSP lyase has been purified and characterized from P. paniculata. Enzymie activity is found in two different proteins: the larger with a molecular weight of 9.26 ± 104 daltons and the smaller with a molecular weight of 3.65 ± 104 daltons. Specific activity of the enzyme is 526 μmols min−1mg−1 for the smaller protein a nd 263 μmols min −1 mg−1 for the la rger protein. The Michaelis‐Menten constant (Km) is 72.8 μM ± 17.15 and the vmax is 1.62 μmols min−1± 0.928 for the 92.6‐kDa protein. The p1 of the larger protein is 5.8 and 5.9 for the smaller protein. Interaction with cysteine protease inhibitors L‐trans‐epoxysuccinyl‐leucylamido (4‐guanidino)‐butane, dithiobis‐(2‐nitrobenzoate), or N‐ethylmaleimide inactivated enzyme activity. The presence of either magnesium or calcium with DMSP lyase enhanced activity al concentrations between 20 and 40 μM but had little effect above these levels. Addition of the divalent chelators ethylenebis(oxyethylenenitrilo) tetraacetic acid and ethylenediaminetetraacetate decreased activity of the enzyme, but activity was restored when either chelator was removed and magnesium or calcium was added to the enzyme.
THE FUCUS (PHAEOPHYCEAE) SPERM RECEPTOR FOR EGGS. I. DEVELOPMENT AND CHARACTERISTICS OF A BINDING ASSAY1
Authors: Wright Philip J. , Green Jonathan R. , Callow James A.
Published: August 2006

To explore the molecular basis of egg‐sperm recognition in the brown alga, Fucus serratus L., we developed an in vitro binding assay involving egg plasma membrane vesicles (PMVs) and proteins contained in a KCl extract of sperm. Binding between the two components was measured using biotinylated PMVs followed by the addition of streptavidin conjugated to alkaline phosphatase and the appropriate substrate. Biotinylation did not affect the ability of egg PMVs to inhibit fertilization in a species‐preferential manner. Binding of labeled egg PMVs to the sperm KCl extract was saturable and competable with unlabeled PMVs but was not species‐specific. Protease treatment of the KCl extract abolished binding, whereas periodate had no effect, suggesting that sperm protein rather than carbohydrate was involved. Preincubation of the sperm extract with sulfated polysaccharides (e.g. fucoidan and ascophyllan) inhibited binding of egg plasma membranes. Sulfation seems to be important for this effect since desulfated fucoidan was far less effective at blocking binding. Polysaccharides which inhibited binding also inhibited fertilization. Overall, the results indicate that at least some aspects of binding between Fucus sperm and eggs are mediated by a protein(s) derived from sperm which recognizes sulfated glycoconjugates on the egg plasma membrane.
SEXUAL DIFFERENTIATION OF GRIFFITHSIA (CERAMIALES, RHODOPHYTA): NUCLEAR PLOIDY LEVEL OF MIXED‐PHASE PLANTS IN G. JAPONICA1
Authors: Lee Yoo Kyung , Choi Han‐Gu , Hong Choo Bong , Kyu Lee In
Published: August 2006

Mixed‐phase plants of Griffithsia japonica Okamura spontaneously occurred in a laboratory culture. Four female plants produced tetrasporangia and spermatangia in addition to their normal female reproductive structures (bisexual/mixed‐phase plants), and four male plants produced tetrasporangia as well as spermatangia (male/mixed‐phase plants). To determine the nuclear ploidy level of these mixed‐phase plants, relative nuclear sizes of male, female, tetrasporangial, and mixed‐phase plants were measured using a microscopic image analysis system. Haploid gametophytes could be distinguished from diploid tetrasporophytes by relative nuclear sizes, with the later having nuclei twice the size of the former. Relative nuclear sizes of the mixed‐phase plants were similar to those of the haploid plants. Thus, the mixed‐phase plants were determined to be haploid. Haploid mixed‐phase plants of G. japonica have a potential to produce male, female and tetrasporangial reproductive structures. Sex determination models are discussed to explain “haploid” mixed‐phase phenomena in red algae.
Native and subunit molecular mass and quarternary structure of the hemoglobin from the primitive branchiopod crustacean Triops cancriformis
Authors: Rousselot Morgane , Jaenicke Elmar , Lamkemeyer Tobias , Harris J. Robin , Pirow Ralph
Published: August 2006

Many branchiopod crustaceans are endowed with extracellular, high‐molecular‐weight hemoglobins whose exact structural characteristics have remained a matter of conjecture. By using a broad spectrum of techniques, we provide precise and coherent information on the hemoglobin of one of the phylogenetically ‘oldest’ extant branchiopods, the tadpole shrimp Triops cancriformis. The hemoglobin dissociated under reducing conditions into two subunits, designated TcHbA and TcHbB, with masses of 35 775 ± 4 and 36 055 ± 4 Da, respectively, determined by ESI‐MS. Nonreducing conditions showed only two disulfide‐bridged dimers, a homodimer of TcHbA, designated D1 (71 548 ± 5 Da), and the heterodimer D2 (71 828 ± 5 Da). Carbamidomethylation of free SH groups revealed the presence of three cysteines per subunit and indicated one intrasubunit and one intersubunit disulfide bridge. Ultracentrifugation and light‐scattering experiments under nondenaturating conditions yielded mass estimates that suggested an uneven number of 17 subunits forming the native hemoglobin. This unrealistic number resulted from the presence of two size classes (16‐mer and 18‐mer), which were recognized by native PAGE and Ferguson plot analysis. ESI‐MS revealed three hemoglobin isoforms with masses of 588.1 kDa, 662.0 kDa, and 665.0 kDa. The 16‐mer and the smaller 18‐mer species are supposed to be composed of TcHbA only, given the dominance of this subunit type in SDS/PAGE. Transmission electron microscopy of negatively stained specimens showed a population of compact molecules with geometrical extensions of 14, 16 and 9 nm. The proposed stoichiometric model of quarternary structure provides the missing link to achieve a mechanistic understanding of the structure–function relationships among the multimeric arthropodan hemoglobins.
Development of an immunological technique for identifying multiple predator–prey interactions in a complex arthropod assemblage
Authors: Hagler J.R.
Published: August 2006

A simplified but highly effective approach for the post‐mortem evaluation of predation on several targeted members of an arthropod assemblage that does not require the development of pest‐specific enzyme‐linked immunosorbent assay (ELISA) (e.g. pest‐specific monoclonal antibodies) or PCR assays (DNA primers) is described. Laboratory feeding studies were conducted to determine if predation events could be detected from predators that consumed prey marked with foreign protein. I determined that large and small rabbit immunoglobulin G (IgG)‐marked prey can be detected by a rabbit‐IgG‐specific ELISA in the guts of chewing and piercing–sucking type predators. I then conducted multifaceted inclusion and exclusion field cage studies to qualify the degree of interguild and intraguild predation occurring among a complex arthropod assemblage during four separate light phase treatments. The field cages contained an arthropod assemblage consisting of 11 or 12 species of predaceous arthropods and three pest species. The three pests introduced into the cages included third instar Trichoplusia ni marked with rabbit IgG, third instar Lygus hesperus marked with chicken IgG and Pectinophora gossypiella sentinel egg masses. The inclusion cages allowed foraging fire ants, Solenopis xyloni, to freely enter the cages while the exclusion cages contained barriers that prevented ant entry. The results obtained using the conventional inclusion/exclusion field cage methodology revealed that there was substantial interguild and intraguild predation occurring on the majority of the arthropods in the assemblage, particularly in those cages that included ants. I then precisely identified which predators in the assemblage were feeding on the three targeted pests by conducting three post‐mortem gut content analyses on each individual predator (1503 individuals) in the assemblage. Specifically, P. gossypiella egg predation events were detected using an established P. gossypiella‐egg‐specific ELISA, and third instar T. ni and L. hesperus predation events were detected using rabbit‐IgG‐specific and chicken‐IgG‐specific ELISAs, respectively. Generally, the gut ELISAs revealed that Collops vittatus, Spanagonicus albofasciatus and Geocoris punctipes readily preyed on P. gossypiella eggs; Nabis alternatus, Zelus renardii and spiders (primarily Misumenops celer) readily preyed on marked L. hesperus nymphs, and spiders, S. albofasciatus and N. alternatus readily preyed on T. ni larvae. Furthermore, the cage methods and the post‐mortem predator gut ELISAs revealed very few distinctive patterns of predation with regard to the light cycle the assemblage was exposed to.
Nickel levels in arthropods associated with Ni hyperaccumulator plants from an ultramafic site in New Caledonia
Authors: BOYD ROBERT S. , WALL MICHAEL A. , JAFFRÉ TANGUY
Published: August 2006

Arthropods (mainly insects) were collected from a forest site that contained at least six species of Ni hyperaccumulators. Whole body Ni analysis was performed for 12 arthropod taxa, two of which were studied at different life cycle stages. We found two Nitolerant insects. The pentatomid heteropteran Utana viridipuncta, feeding on fruits of the Ni hyperaccumulator Hybanthus austrocaledonicus, contained a mean of 2 600 μNi/g in nymphs and 750 μNi/g in adults. The tephritid fly Bactrocera psidii, feeding on pulp of Sebertia acuminata fruits that contained 6 900 μNi/g, contained 420 μNi/g as larvae that had evacuated their guts and significantly less (65 μNi/g) as adults. European honeybees (Apis mellifera) visiting flowers of the Ni hyperaccumulator H. austrocaledonicus contained significantly more Ni (8‐fold more) than those collected from flowers of Myodocarpus fraxinifolius, a non‐hyperaccumulator. Our results show that some insects feed on Ni hyperaccumulator plants and that their feeding mobilizes Ni into local food webs.
Impact of transgenic Bacillus thuringiensis cotton on a non‐target pest Tetranychus spp. in northern China
Authors: MA XIAO‐MU , LIU XIAO‐XIA , ZHANG QING‐WEN , LI JI‐JUN , REN AI‐MIN
Published: August 2006

Field studies were carried out to evaluate the effect of two transgenic cotton varieties (SGK321 carrying Cry1A+CpTI and DP99B carrying Cry1Ac) and the conventional variety (shiyuan321‐parental line of SGK321) on spider mites, Tetranychus spp. from 2002 to 2004. In 2002, this experiment included three treatments: Bt cotton field (SGK321) treated with acaricides against spider mites, untreated non‐Bt cotton field (Shiyuan321), and untreated Bt cotton field (SGK321). In 2003–2004, there are four types of treatments after a new transgenic Bt cotton variety, DP99B (non‐chemical control), was added into the experiments. The results showed that there were no significant difference in densities of spider mites among Bt without acaricides and non‐Bt without acaricides cotton fields, nor was there a significant difference in damage of spider mites to cotton among these treatments (P > 0.1). However, there are significant differences (P < 0.05) in densities of spider mites and damage caused by spider mites between cotton fields with and without acaricides. Acaricide significantly reduced the densities of spider mites in Bt cotton (P < 0.05). These results suggest that Bt cotton has no effect on spider mites populations. However, spider mites have the potential for severe damage in Bt cotton fields. Acaricides are essential tools in controlling cotton spider mites in northern China.
Effects of seed type and bruchid genotype on the performance and oviposition behavior of Zabrotes subfasciatus (Coleoptera: Bruchidae)
Authors: CAMPAN ERICK D. M. , BENREY BETTY
Published: August 2006

The effect of different bean varieties on the performance of the bruchid beetle Zabrotes subfasciatus Boheman (Coleoptera: Bruchidae), was determined by using wild and cultivated seeds of the genus Phaseolus. Results showed that the quality of the host plant affected the performance and the oviposition behavior of female beetles. Overall, bruchid performance was higher on cultivated seeds than on wild seeds. It was also found that the oviposition behavior and the performance of their offspring differed between females that originated from wild versus cultivated seeds. We also demonstrated the importance of a genetic component in bruchid performance: longevity, fecundity, larval development, adult size, and the sex ratio of the progeny varied according to their maternal lineage (‘familyrsquo;). For example, on the same host type, some females laid twice as many eggs as females from other ‘familiesrsquo;, and the sex ratio among the offspring correlated with that of their mother. Thus, the performance and behavior of Z. subfasciatus are not only affected by environmen tal factors such as the quality of the seeds on which they develop, but also have a genetic basis which can counterbalance a less suitable quality of the host plant. For a crop pest such as Z. subfasciatus, its ability to survive and adapt on host plants of differing quality may be an important attribute to consider for pest management.
Relationship between systemic nitric oxide metabolites and cyclic GMP in healthy male volunteers
Authors: Metzger I. F. , Sertorio J. T. C. , Tanus‐Santos J. E.
Published: August 2006

Aim:  Nitric oxide (NO) is an endogenous mediator of many physiological processes, many of which are mediated by cyclic guanosine 3′,5′‐monophosphate (cGMP). Much effort has been made to validate clinical markers of NO production or bioavailability. While the measurement of plasma nitrate, nitrite, and cGMP concentrations have been suggested to reflect endogenous production of NO, there is no study showing whether there is correlation between these three markers. In the present study, we investigate whether there is correlation between the plasma concentrations of nitrate, nitrite, and cGMP in a relatively homogeneous group of 141 healthy subjects.

Methods:  Venous blood samples were collected from healthy male subjects and plasma aliquots were then immediately removed and stored at −70 °C until analysed in duplicate for their nitrite and nitrate content using ozone‐based chemiluminescence assays. Plasma cGMP levels were determined by using a commercial enzyme immunoassay.

Results:  While we found no significant correlation between plasma nitrite and nitrate concentrations (P = 0.747), or between plasma nitrate and cGMP concentrations (P = 0.221), a significant positive correlation was found between plasma cGMP and nitrite concentrations (P = 0.017, rs = 0.270).

Conclusions:  The significant correlation we found between plasma nitrite and cGMP concentrations is consistent with the notion that nitrite or cGMP concentrations in plasma may be useful clinical markers of NO formation in healthy subjects.
Distortion-product otoacoustic emission suppression growth in normal and noise-exposed rabbits
Authors: Porter Christopher A. , Martin Glen K. , Stagner Barden B. , Lonsbury-Martin Brenda L.
Published: August 2006

This study investigated noise-induced changes in suppression growth (SG) of distortion product otoacoustic emissions (DPOAEs). Detailed measurements of SG were obtained in rabbits as a function of f2 frequencies at four primary-tone levels. SG measures were produced by using suppressor tones (STs) presented at two fixed distances from f2. The magnitude of suppression was calculated for each ST level and depicted as contour plots showing the amount of suppression as a function of the f2 frequency. At each f2, SG indices included slope, suppression threshold, and an estimate of the tip-to-tail value. All suppression measures were obtained before and after producing a cochlear dysfunction using a monaural exposure to a 2-h, 110-dB SPL octave-band noise centered at 2kHz. The noise exposure produced varying amounts of cochlear damage as revealed by changes in DP-grams and auditory brainstem responses. However, average measures of SG slopes, suppression thresholds, and tip-to-tail values failed to mirror the mean DP-gram loss patterns. When suppression-based parameters were correlated with the amount of DPOAE loss, small but significant correlations were observed for some measures. Overall, the findings suggest that measures derived from DPOAE SG are limited in their ability to detect noise-induced cochlear damage.
Testing the odontocete acoustic prey debilitation hypothesis: No stunning results
Authors: Benoit-Bird Kelly J. , Au Whitlow W. L. , Kastelein Ronald
Published: August 2006

The hypothesis that sounds produced by odontocetes can debilitate fish was examined. The effects of simulated odontocete pulsed signals on three species of fish commonly preyed on by odontocetes were examined, exposing three individuals of each species as well as groups of four fish to a high-frequency click of a bottlenose dolphin [peak frequency (PF) 120kHz, 213-dB peak-to-peak exposure level (EL)], a midfrequency click modeled after a killer whale’s signal (PF 55kHz, 208-dB EL), and a low-frequency click (PF 18kHz, 193-dB EL). Fish were held in a 50-cm diameter net enclosure immediately in front of a transducer where their swimming behavior, orientation, and balance were observed with two video cameras. Clicks were presented at constant rates and in graded sweeps simulating a foraging dolphin’s “terminal buzz.” No measurable change in behavior was observed in any of the fish for any signal type or pulse modulation rate, despite the fact that clicks were at or near the maximum source levels recorded for odontocetes. Based on the results, the hypothesis that acoustic signals of odontocetes alone can disorient or “stun” prey cannot be supported.