bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of antiretroviral therapy on visfatin and retinol‐binding protein 4 in HIV‐infected subjects
Authors: Schindler K. , Haider D. , Wolzt M. , Rieger A. , Gmeinhart B. , Luger A. , Nowotny P. , Ludvik B.
Published: August 2006

Background  To determine circulating levels of adipocytokines, especially the recently characterized visfatin, and the fat‐derived factor retinol‐binding protein‐4 (RBP‐4) in HIV‐infected subjects and their respective changes following treatment with highly active antiretroviral therapy (HAART).

Materials and methods  Fourteen HIV‐positive, HAART‐naïve subjects were compared with 10 HIV‐negative healthy controls and reassessed after a 1‐year treatment with HAART. Plasma visfatin and RBP‐4 were determined by ELISA, whereas leptin and adiponectin by RIA. Body composition was measured with dual X‐ray absorptiometry (DXA). Homeostasis model assessment (HOMA‐IR) was assessed using insulin and glucose levels.

Results  Visfatin and RBP‐4 levels in HIV‐positive subjects were comparable with those of HIV‐negative controls before treatment with HAART. Treatment with HAART for 12 months resulted in a 6·9‐fold and 7·1‐fold increase of visfatin and RBP‐4 levels (+54·0 ± 9·7 ng mL−1, P < 0·0001 and +95·3 ± 31·7 ng mL−1, P < 0·01), respectively. Leptin (−2·7 ± 1·6 ng mL−1, P = 0·054) was unchanged and adiponectin (−2·8 ± 0·7 µg mL−1, P < 0·01) decreased. Changes of visfatin concentrations correlated significantly with the increases of RBP‐4 (r = 0·78, P = 0·001), fat‐free mass (FFM, r = 0·75, P < 0·05) and change of HOMA‐IR (r = 0·64, P < 0·05). Parameters of glucose metabolism and body fat mass were unchanged during the observation period.

Conclusions  Treatment with HAART induced a pronounced increase of plasma visfatin and RBP‐4 as well as a decrease of adiponectin in HIV‐infected patients on HAART. Although body weight, fat mass and parameters of glucose metabolism remained stable, the changes in the adipocytokines might herald subsequent alterations of these parameters.
Hearing loss in Fabry disease: data from the Fabry Outcome Survey
Authors: Hegemann S. , Hajioff D. , Conti G. , Beck M. , Sunder‐Plassmann G. , Widmer U. , Mehta A. , Keilmann A.
Published: August 2006

Background  Hearing loss is a common symptom in Fabry disease, but neither its natural course nor its aetiology has been defined precisely. The aim of this study was to provide a detailed epidemiological description of hearing impairment in patients in the Fabry Outcome Survey (FOS), which is the largest available database of Fabry patients.

Materials and methods  Questionnaires were completed by 566 Fabry patients, of whom 316 reported ear‐related symptoms. Pure‐tone audiograms from 86 patients, performed before starting enzyme replacement therapy, were analysed and compared with age‐ and sex‐specific normal values (International Organization for Standardization, ISO 7029).

Results  When compared to an age‐matched population (ISO 7029), 74% of patients had a threshold elevated above the 95th centile in at least one tested frequency. All frequencies were affected to a similar degree. However, only 14 patients (16%) were clinically affected by hearing impairment according to the age‐independent World Health Organization (WHO) classification (mean threshold at 0·5, 1 and 2 kHz worse than 25 dB). Hearing loss was sensorineural in 63 patients (73%) of whom 7 patients (8%) had also a conductive component. One patient had a purely conductive hearing loss. Episodes of sudden hearing loss seemed to occur more frequently than in the general population. Men were affected earlier and more severely than women.

Conclusions  Hearing in Fabry disease is significantly worse than in an age‐matched general population but leads to clinically relevant hearing impairment in only 16% of cases. It resembles accelerated presbycusis with an additional Fabry‐specific strial‐type hearing loss.
Autoantibody against β1‐adrenergic receptor and left ventricular remodeling changes in response to metoprolol treatment
Authors: Miao G. B. , Liu J. C. , Liu M. B. , Wu J. L. , Zhang G. , Chang J. , Zhang L.
Published: August 2006

Abstracts

Background  Autoantibodies specific for the β1‐adrenoceptor (β1‐AR) have been implicated in the pathology of congestive heart failure (CHF). We hypothesized that the presence of autoantibodies against β1‐AR (anti‐β1‐AR) is associated with left ventricular (LV) remodelling in response to metoprolol.

Materials and methods  Synthetic β1‐AR peptides served as the target antigen in an ELISA (enzyme‐linked immunosorbent assay) were used to screen the sera of 106 CHF patients. Patients were separated into positive (+) anti‐β1‐AR or negative (–) anti‐β1‐AR groups according to their anti‐β1‐AR reactivity. Echocardiography (ECG) was performed at baseline and after one year of metoprolol therapy in combination with standard treatment regime for CHF, that is, digoxin, diuretics and an ACEI (angiotensin‐converting enzyme inhibitor). The dose of metoprolol was doubled on a biweekly basis up to 50 mg × 2 daily (b.i.d./day) or attainment of maximum tolerated dose.

Results  Ninety‐six patients completed final data analysis. Fifty‐four patients with (+) anti‐β1‐AR had greater improvements than 42 patients with (–) anti‐β1‐AR in LVEDD (left ventricular end‐diastolic dimension) (P < 0·01, from 69 ± 0·8 to 58·0 ± 0·5 mm vs. 69·0 ± 0·8–63·6 ± 0·9 mm) and LVESD (left ventricular end‐systolic dimension) (P < 0·01, from 57·1 ± 1·4 to 43·9 ± 0·8 mm vs. 56·2 ± 0·9–48·6 ± 1·0 mm), and LVEF (left ventricular ejection fraction) (P < 0·01, from 35·4 ± 1·3 to 49·8 ± 0·6% vs. 34·4 ± 1·0–44·3 ± 1·1%) by metoprolol therapy in combination with standard treatment regime for one year. Of the CHF patients with (+) anti‐β1‐AR, 65·4% responded to target metoprolol dose as compared to 21·4% of CHF patients without anti‐β1‐AR (P < 0·01). Response to target metoprolol dose occurred more rapidly in (+) anti‐β1‐AR than (–) anti‐β1‐AR of CHF patients (67·5 ± 2·4 vs. 100·8 ± 3·0 days, P < 0·01).

Conclusion  These results demonstrated that CHF patients with (+) anti‐β1‐AR had greater improvements in LV remodelling and heart function by metoprolol as compared to (–) anti‐β1‐AR patients. Moreover, patients with (+) anti‐β1‐AR have better tolerance to metoprolol therapy than patients without anti‐β1‐AR.
Genetic relationships among American species of the genus Prosopis (Mimosoideae, Leguminosae) inferred from ITS sequences: evidence for long‐distance dispersal
Authors: Bessega C. , Vilardi J. C. , Saidman B. O.
Published: August 2006

Aim  The genus Prosopis includes 44 species and has a pseudoamphitropical, disjunct distribution. We aimed to determine whether American Prosopis sections arose in North or South America, and to explain the current distribution of their species on the basis of their genetic relationships.

Location  South‐western USA, Mexico, Caribbean Antilles, Peru–Ecuador, central and northern Argentina, south‐western Argentina (Patagonia) and Cuyo, south‐western Asia and northern Africa.

Methods  Internal transcribed spacer fragments from 21 species of Prosopis were sequenced and the data were used to analyse the phylogenetic relationships using Microlobius and Mimosa as outgroups. Genetic distances were calculated to estimate the degree of divergence. Dispersal–vicariance (DIVA) analysis was conducted to help understand the biogeographical history of the genus.

Main conclusions  The sections Strombocarpa and Algarobia are not monophyletic. Prosopis argentina (section Monilicarpa) and the species of Algarobia are included in single clade. The phylogeny, DIVA analysis, and the pattern of genetic distances indicate that the ancestral area for the American species was wide, from south‐western USA to Central and northern Argentina. Successive vicariance events split this area, and long‐distance dispersal episodes (perhaps mediated by birds) led to recolonizations from North to South America, and vice versa.
Pre‐experimental stress in patients with irritable bowel syndrome: high cortisol values already before symptom provocation with rectal distensions
Authors: Walter S. A. , Aardal‐eriksson E. , Thorell L. H. , Bodemar G. , Hallböök O.
Published: August 2006

Abstract  Stress is known to affect symptoms of irritable bowel syndrome (IBS) probably by an alteration of visceral sensitivity. We studied the impact of maximal tolerable rectal distensions on cortisol levels in patients with IBS, chronic constipation and controls, and evaluated the effect of the experimental situation per se. In twenty‐four IBS patients, eight patients with chronic constipation and 15 controls salivary cortisol was measured before and after repetitive maximal tolerable rectal balloon distensions and at similar times in their usual environment. Rectal sensitivity thresholds were determined. IBS patients but not controls and constipation patients had higher cortisol levels both before and after the experiment compared with similar times on an ordinary day in their usual environment (P = 0.0034 and 0.0002). There was no difference in salivary cortisol level before compared with after rectal distensions. The IBS patients had significantly lower thresholds for first sensation, urge and maximal tolerable distension than controls (P = 0.0247, 0.0001 and <0.0001) and for urge and maximal tolerable distension than patients with constipation (P = 0.006 and 0.013). IBS patients may be more sensitive to expectancy stress than controls and patients with constipation according to salivary cortisol. Rectal distensions were not associated with a further significant increase in cortisol levels.
Genome‐scale Assessment of Molecular Pathology in Systemic Autoimmune Diseases using Microarray Technology: A Potential Breakthrough Diagnostic and Individualized Therapy‐design Tool
Authors: Centola M. , Frank M. B. , Bolstad A. I. , Alex P. , Szanto A. , Zeher M. , Hjelmervik T. O. , Jonsson R. , Nakken B. , Szegedi G. , Szodoray P.
Published: August 2006

Systemic autoimmune rheumatic diseases are of complex aetiology, characterized by an intricate interplay of various factors. A myriad of genes lies behind the heterogeneous manifestations of these diseases, and the overexpression and repression of particular genes form a specific gene‐expression profile (genetic fingerprints) that is characteristic to the given disease phenotype. Besides the description of various cell types by using gene‐expression profiling, the data should be directly applicable to the design of individual therapeutic protocols for patients suffering from various autoimmune diseases. In this review, we summarize the gene‐expression profile, various genetic signatures of different autoimmune diseases and give an overview on the possible interpretations of the data. The application of recent breakthroughs in high‐throughput molecular profiling technologies, such as microarray technology has been the basis for a revolution in biomedical research, as well as diagnostics and pharmaceutical development. It is easy to envision a day when personalized medicine, which is the diagnosis and treatment of a given patient with agents and procedures tailored to that patient's genetics, physiology and pathology, will become the standard of care.
Pax5 – a Critical Inhibitor of Plasma Cell Fate
Authors: Nera K.‐P. , Lassila O.
Published: August 2006

Paired box protein 5 (Pax5) is essential for early B cell commitment as well as for B cell development, and continuous expression of Pax5 is required throughout the B cell lineage to maintain the functional identity of B cells. During B cell activation, Pax5 is downregulated before terminal differentiation into antibody‐secreting plasma cells, and enforced expression of Pax5 prevents plasmacytic development. Recently, loss of Pax5 was shown to result in the substantial transition to a plasma cell state, demonstrating a functionally significant role for Pax5 in the regulation of terminal B cell differentiation. Here we elucidate the current understanding about the function of Pax5 as a key inhibitor of plasma cell differentiation.
Role of Dendritic Cells in Sjögren's Syndrome
Authors: Vogelsang P. , Jonsson M. V. , Dalvin S. T. , Appel S.
Published: August 2006

Sjögren's syndrome (SS) is a chronic inflammatory and lymphoproliferative autoimmune disease of unknown aetiology. It is characterised by progressive mononuclear cell infiltration of the salivary and lacrimal glands and a decreased glandular secretion, resulting in dryness of the mouth and eyes (xerostomia and keratoconjunctivitis sicca, respectively). Dendritic cells (DC) are considered to be the most potent antigen‐presenting cells. Because of their central role in initiating an immune response while maintaining tolerance, impaired function of these cells might lead to the break of peripheral tolerance and initiation of immune responses to self‐antigens. This review will focus on the possible role of DC in SS.
An Optimized Method for the Functional Analysis of Human Regulatory T Cells
Authors: Oberg H.‐H. , Wesch D. , Lenke J. , Kabelitz D.
Published: August 2006

Naturally occurring regulatory T cells (Treg) suppress the activation of antigen‐responsive T cells in a cell contact‐dependent manner. In order to investigate the impact of soluble mediators and receptor–ligand interactions on the interplay between naive T cells and Treg, a reproducible suppressor cell assay which functions in the absence of additional feeder cells or antigen‐presenting cells is mandatory. Here, we describe such a method which is suited to study the modulation of responder T cell/Treg interactions in vitro. Treg were isolated from negatively purified total human CD4+ T cells by positive selection using anti‐CD25 monoclonal antibody (MoAb)‐coated Dynabeads followed by a detachment step. The remaining CD4+ CD25− responder T cells were cocultured with CD4+ CD25+ Treg in the presence of T‐cell Activation/Expansion Beads from Miltenyi Biotec pre‐coated with anti‐CD3 plus anti‐CD28 monoclonal antibody (MoAb). The optimal concentration for coating was 5 μg/ml for both MoAb. At this concentration, strong proliferation of responder T cells was elicited which was almost completely suppressed by Treg at 1:1 cell ratios. When higher concentrations of anti‐CD3/anti‐CD28 MoAb were used for coating, Treg also showed some degree of proliferation. The optimized suppressor assay proved to be highly reproducible and was used here to confirm the partial or complete reversal of Treg‐mediated T‐cell suppression by some cytokines (IL‐2, IL‐15), soluble IL‐6 receptor/IL‐6 fusion protein and recombinant GITR‐ligand. Furthermore, our data confirm that Treg do not need other cell types to suppress proliferation of CD4+ CD25− responder T cells.
The ghost of unbalanced species distribution data in geographical model predictions
Authors: Jiménez‐Valverde A. , Lobo J. M.
Published: August 2006

Unbalanced samples are considered a drawback in predictive modelling of species’ potential habitats, and a prevalence of 0.5 has been extensively recommended. We argue that unbalanced species distribution data are not such a problem from a statistical point of view, and that good models can be obtained provided that the right predictors and cut‐off to convert probabilities into presence/absence are chosen. The effects of unbalanced prevalence should not be confused with those of low‐quality data affected by false absences, low sample size, or unrepresentativeness of the environmental and spatial gradient. Finally, we point out the necessity of greater research effort aimed at improving both the quality of training data sets, and the processes of validating and testing of models.
Spread and current potential distribution of an alien grass, Eragrostis lehmanniana Nees, in the southwestern USA: comparing historical data and ecological niche models
Authors: Schussman Heather , Geiger Erika , Mau‐Crimmins Theresa , Ward Judy
Published: August 2006

The potential distribution of alien species in a novel habitat often is difficult to predict because factors limiting species distributions may be unique to the new locale. Eragrostis lehmanniana is a perennial grass purposely introduced from South Africa to Arizona, USA in the 1930s; by the 1980s, it had doubled its extent. Based on environmental characteristics associated with its introduced and native range, researchers believed that E. lehmanniana had reached the limits of its distribution by the early 1990s. We collected data on E. lehmanniana locations from various land management agencies throughout Arizona and western New Mexico and found new records that indicate that E. lehmanniana has continued to spread. Also, we employed two modelling techniques to determine the current potential distribution and to re‐investigate several environmental variables related to distribution. Precipitation and temperature regimes similar to those indicated by past research were the most important variables influencing model output. The potential distribution of E. lehmanniana mapped by both models was 71,843 km2 and covers a large portion of southeastern and central Arizona. Logistic regression (LR) predicted a potential distribution of E. lehmanniana more similar to this species current distribution than GARP based on average temperature, precipitation, and grassland species composition and recorded occurrences. Results of a cross‐validation assessment and extrinsic testing showed that the LR model performed as well or better than GARP based on sensitivity, specificity, and kappa indices.
Visual outcomes for optic nerve sheath fenestration in pseudotumour cerebri and related conditions
Authors: Chandrasekaran Sujatha , McCluskey Peter , Minassian Darwin , Assaad Nazih
Published: August 2006

Abstract

Background:  To determine the efficacy and safety of optic nerve sheath fenestration, and to identify factors predicting visual field (VF) and visual acuity (VA) in patients with progressive pseudotumour cerebri syndrome.

Methods:  This retrospective observational case series studied 51 eyes of 32 patients with pseudotumour cerebri syndrome, by chart review and comparison of preoperative and postoperative examinations. Main outcome measures included VF, VA and complications.

Results:  Postoperative VF mean deviation scores improved (P = 0.03) within 6 months when compared with preoperative VF. Multiple regression analysis demonstrated that eyes with mean deviation ≥ −20 dB were associated with improved or stabilized VA at 6 months, odds ratio 7.5 and confidence interval (1.2, 46.1), P = 0.03. Eyes with VF defects outside 10° of fixation were associated with improved or stabilized VF at 6 months odds ratio 9.7, 95% confidence interval 1.1, 85.9, P = 0.04. Five patients developed self‐limiting complications from surgery.

Conclusions:  Optic nerve sheath fenestration is safe and effective in stabilizing or improving VF and VA in the short to medium term. Patients with mild VF loss improved following surgery, and patients with severe VF loss stabilized following surgery.
Prognostic indicators for open globe injury
Authors: Rofail Marc , Lee Graham A , O’Rourke Peter
Published: August 2006

Abstract

Background:  The purpose of the study is to identify factors predictive of outcome after open globe injury in 273 patients admitted to the Royal Brisbane Hospital, Queensland, Australia between 1992 and 2003.

Methods:  Data were collected retrospectively regarding demographic and geographical factors, injury circumstances, initial visual acuity (VA), injury parameters, details of initial and subsequent surgery, final best corrected VA and complications. Multivariate analysis using binary logistic regression was utilized to identify which factors were related to outcome.

Results:  83% of patients were male, with a mean age of 38.3 years. The mean duration of follow up was 16.6 months and 58% of patients (135 of 231) achieved an overall improvement in their vision. Forty‐one cases (15%) were enucleated, with half of these cases performed primarily. The prognostic factors indicating the likelihood of a VA of counting fingers or worse were poor initial VA, a large laceration >10 mm and the presence of a relative afferent pupil defect. Rural patients had a significantly worse final VA than city dwellers and had higher rates of endophthalmitis and enucleation.

Conclusions:  Assessment of prognostic factors at the time of presentation of an open globe injury enables realistic expectations of final visual outcome by the doctor and the patient. In order to improve outcomes in patients from rural areas, access to specialized eye services need to be upgraded.
Ophthalmology in proverbs and aphorisms
Authors: Mansour Ahmad M , Hamam Rola N , Mehio‐Sibai Abla
Published: August 2006

Abstract

After a comprehensive review of available texts and literature covering five millennia, the authors present a collection of ophthalmic proverbs and aphorisms with an examination of their applicability within current medical knowledge. A total of 74 ophthalmic proverbs and aphorisms were retrieved from 130 texts and divided into seven categories: (i) importance of vision (‘The eyes, like sentinels, hold the highest place in the body’); (ii) definition of blindness and anatomical observations (‘The eye is protected by the lashes, eyebrows, and orbit’); (iii) diseases of the eye such as presbyopia, sensitivity to light and dry eye (‘Tear in the eye is jewel’); (iv) the eye as a window of the body; (v) vulnerability of the eye (‘The eye cannot oppose an awl’); (vi) health behaviours and protection of sight (‘Be gentle with two: women and eyes’), and finally; and (vii) nutrition and vision (‘Carrots improve vision’). The majority of these proverbs and aphorisms can be used as a guide, not for prognosis, diagnosis or cure, but rather for ocular health promotion.
Impact of the malaria parasite on reproductive indices of male mice
Authors: RAJI YINUSA , AKINSOMISOYE OLUMIDE S. , AZEEZ MISTURA O.
Published: August 2006

Aim:  To investigate the impact and possible mechanism of action of the rodent malarial parasite on reproduction.

Methods:  Male albino mice were infected with 15, 30 and 45%Plasmodium berghei berghei through inoculation with 107 parasitized red blood cells. Each experiment had its own control that was not infected with P. berghei berghei. Mice infected with 15%P. berghei berghei were killed on days 0, 5, 10 and 15; those infected with 30%P. berghei berghei were killed on days 0, 3, 6 and 10; and those infected with 45%P. berghei berghei were killed on days 1–7 after infection. Caudal epididymal sperm motility, counts and morphology, body and wet organ weights and hematological indices were determined.

Results:  The results showed a progressive duration dependent decrease in sperm motility, sperm count and viability (P < 0.01) in parasitized mice. There were significant decreases in serum testosterone and increases in cortisol levels (P < 0.05) in the infected mice compared with the controls. There was also a progressive decrease (P < 0.05) in red blood cell count and packed cell volume. However, there was a progressive increase (P < 0.01) in white blood cell count and weight of the spleen and liver. There was no significant change in weight of the testis and epididymides.

Conclusion:  The results suggest that the malaria parasite could depress male fertility indices. (Reprod Med Biol 2006; 5: 201–209)
Effect of relaxin on motility, acrosome reaction and viability of cryopreserved boar spermatozoa
Authors: MIAH ABDUL GAFFAR , HOSSAIN MD SHAROARE , TAREQ KMA , SALMA UMMAY , HAMMANO KO‐ICHI , KOHSAKA TETSUYA , TSUJII HIROTADA
Published: August 2006

Background and Aims:   Relaxin has an important role in stimulating motility and the acrosome reaction (AR) of fresh boar spermatozoa. The objective of the present study was to determine whether relaxin can improve the motility, AR and viability of cryopreserved boar spermatozoa.

Methods:   Cryopreserved boar spermatozoa were thawed, washed and incubated at 37°C for 4 h in modified Beltsville thawing solution supplemented with 0, 20 or 40 ng/mL relaxin. Sperm motility, AR, viability, and incorporation and oxidation of 14C‐glucose were evaluated during 0–4 h of incubation.

Results:  The results show that the supplementation of relaxin (especially at 20 ng/mL) in the thawing solution improved sperm motility significantly (P < 0.05) at 1–3 h of incubation. The percentage of acrosome reacted live spermatozoa was improved significantly (P < 0.05) when the spermatozoa were treated with 20 ng/mL relaxin. Viability was not significantly (P > 0.05) improved by supplementation with relaxin. The rates of incorporation and oxidation of 14C‐glucose were increased in correlation with AR up to 4 h of incubation.

Conclusion:  We conclude that relaxin can improve the sperm motility and AR, and enhance the glucose metabolism of cryopreserved boar spermatozoa. (Reprod Med Biol 2006; 5: 215–220)
Globalization and sustainable consumption of shrimp: consumers and governance in the global space of flows
Authors: Oosterveer Peter
Published: August 2006

The ongoing process of globalization in food provision is transforming the relationships between producers and consumers as well as the conventional role of governments in regulating the environment. Consumers are increasingly concerned about the environmental and social impacts of food production in developing countries and many are willing to take action. Conceptualizing globalization as the coming about of the network society offers an adequate basis for analysing transitions in food governance including new ways of consumer involvement. The case of shrimp produced through aquaculture in Thailand and consumed worldwide shows how innovative food governance arrangements appear in the context of global modernity. Authority and power in such arrangements are shifting away from national governments and towards producers, processors, traders and consumers along the supply chain.
Understanding postorganic fresh fruit and vegetable consumers at participatory farmers’ markets in Ireland: reflexivity, trust and social movements
Authors: Moore Oliver
Published: August 2006

This paper examines how trusting relations between consumers and vendors of organic fresh fruits and vegetables (FFVs) in a particular type of farmers’ market (FM) in Ireland are established and maintained, and what the implications of this are. First, the food system is outlined, and then its attendant problems. These problems have led to various solutions, two of which are organic food and FMs. Then, the growth in these two areas is outlined, as is the accompanying growth in the academic literature on these two areas, some of which overlaps. Various pressures, including in particular the increasing distance food travels and disconnected stallholders and products at the FM, are suggested. In light of this, a need to apply an understanding of the reflexive consumer, trust and social movements is suggested. It is found that the consumers interviewed act reflexively by choosing to go to these FMs. They prioritize the trusting relationships built up through repeated personal contact at these FMs over and above organic certification. Along with and as part of this, they prioritize local, fresh, seasonal ‘chemical‐free’ FFVs over and above imported certified organic produce. Various aspects of collective identity formation, including modes of behaviour, objects and stories, and language, are involved in this process. These elements, to some extent, act as a buffer against the pressures of distance and disconnection. Along with this, the essential meaning of the word organic is, in this particular context, reconstructed to include various socio‐environmental values missing from some certified organic produce. The word postorganic is suggested. The main methodologies used are semistructured in‐depth interviews and participant observation.
Political consumerism between individual choice and collective action: social movements, role mobilization and signalling
Authors: Holzer Boris
Published: August 2006

The notion of political consumerism has two implications. First, consumers wield some kind of power that they can use to effect social change through the marketplace. Second, political consumerism refers to and somehow combines the rationalities of two subsystems, politics and the economy. Yet regarding their everyday, individualized shopping decisions, consumers do not appear to command a great deal of power. What kind of influence, then, can individual economic decisions have on producers? Is that influence robust enough to attribute power to consumers? And if consumers do indeed have power, how can we conceive the implied translation of political concerns into the monetary logic of the economy? An answer to those questions needs to take into account the societal context of political consumerism. This paper analyses how political consumerism relates to the functional differentiation of modern society and how social movements are fundamental to understanding it. Through what I shall call role mobilization, social movements turn the role sets of their supporters into transmission belts for political objectives, and by authoritatively communicating those objectives, they provide signals to producers, who otherwise would not know a great deal about their consumers’ preferences.
CHROMATIC REGULATION OF QUANTUM YIELDS FOR PHOTOSYSTEM II CHARGE SEPARATION, OXYGEN EVOLUTION, AND CARBON FIXATION IN HETEROCAPSA PYGMAEA (PYRROPHYTA)1
Authors: Kroon Bernd , Prézelin Barbara B. , Schofield Oscar
Published: August 2006

Operational and maximum quantum yields for system (PSII) charge separation, oxygen evolution, and carbon fixation were quantified and compared for Heterocapsa pygmaea Loeblich, Schmidt et Sherley populations chromatically adapted to white, green, blue, and red light. Significant variability in quantum yields was induced by chromatic adaptation alone or when chromatically adapted cells were suddenly exposed to biased light fields (i.e. white light). Results indicated a close coupling between the variability in quantum yields for PSII charge separation and oxygen evolution, but not between quantum yields for oxygen evolution and carbon fixation. But not between quantum yields for oxygen evolution and carbon fixation. The ability to regrlate and optimize light energy distribution between PSII and photosystem I (PSI) appears to be the mechanism underlying chromatic adaptation for PSII charge separation and oxygen evolution. Conceptually, the resulting impacts on PSI cyclic electron transport rates could account for observed variability in quantum yields for oxygen evolution and some variability in quantum yields for carbon fixation. Similarly, enzymatic processes associated with organic carbon synthesis appeared to be variably dependent on spectral growth irradiances and contributing to the observed variability in quantum yields for carbon fixation. The relevance of these findings to the in situ primary production is discussed.
THE RPS12 GENE IN SPROGYRA MAXIMA (CHLOROPHYTA) AND ITS EVOLUTIONARY SINGNIFICANCE1
Authors: Lew Kathey A. , Manhart James R.
Published: August 2006

The str operon consists fo four genes in eubacteria. Portions of his operon are conserved in the chloroplast genomes of green algae and land plants. In land plant chloroplasts, the str operon comprises only two genes, rps12 and rps7, and is arranged in a trans‐spliced state. Since no other previously studied chloroplast genome contains this arrangement, and because the charophyte lineage is the sister group of land plants, we chose to look for this arrangement in the Charophyceae. The two str genes, rps12 and rps7, present in the chloroplasts of Spirogyra maxima Hanssall, were identified by hybridization of a Southern blot and requenced. The results indicate that Spirogyra contains a str operon almost identical to that of land plant chloroplasts. Based upon the structure of the operon in other chloroplasts and eubacterial genomes, the trans‐spliced state most likely evolved early within the charophyte lineage.
MOLECULAR ANALYSIS REVEALS CRYPTIC DIVERSITY IN PORPHYRA (RHODOPHYTA)1
Authors: Stiller John W. , Waaland J. Robert
Published: August 2006

The small subunit ribosomal RNA (SSU rRNA) gene was amplified from 15 species of the red alga Porphyra and digested with restriction enzymes to generate data for species identification. The subset of species selected for phylogenetic analysis was P. cuneiforms (Setchell et Hus) Krishnamurthy, P. nereocystis anderson, P. schizophylla Hollenberg et Abbott, P. thuretii Setchell et Dawson and Porphyra 1674. Bangia sp. was used as an out‐group. Restriction sites were mapped and used as characters in parsimony and maximum likelihood analysis. The phylogenetic hypotheses generated were compared statistically to possible alternative phylogenies based on traditional morphological taxonomic characters. The results indicate that the current subgenera in Porphyra do not represent monophyletic groups and that traditional morphological and ecological taxonomic characters alone may not be adequate for definitive species identification and cannot be relied on as an indication of Porphyra have large insertions in the SSU gene that are apparently splicesd from the final SSU rRNA molecule. The possible character, distribution and potential significance of these putative introns are discussed.
PREDICTING DESICCATION STRESS IN MICROSCOPIC ORGANISMS THE USE OF AGAROSE BEADS TO DETERMINE EVAPORATION WITHIN AND BETWEEN INTERTIDAL MICROHABITATS1
Authors: Brawley Susan H. , Johnson Ladd E.
Published: August 2006

We describe an easy and inexpensive way to determine whether intertidal microhabitats remain wet during tidal emersion. This new technique uses agarose beads (120 üm diameter when fully hydrated) that shrink in a graded fashion as they dry. The agarose beads allow variability in surface wetness to be gauged over distances of less than 1 mm. Describe this parameter of microclimate is important in order to predict the likelihood and spatial pattern of survival of settled larvae, reproductive propagules, and other microscopic stages in the life histories of organisms growing in intertidal and other water‐stressed environments. For the brown seaweed Pelvetia fastigiata (J. Ag.) DeToni (Fucales, Phaeophyta), the use of agarose beads demonstrated that survival of zygotes during tidal emersion was highes at those sites that remain damp. Temperature alone was found to be an unreliable measure of wetness within a single microhabitat (e.g. red algal turf).
RELATIONSHIP BETWEEN NUCLEOSIDE DIPHOSPHATE KINASE ACTIVITY AND LIGHT‐LIMITED GROWTH RATE IN THE MARINE DIATOM THALASSIOSIRA PSEUDONANA (BACILLARIOPHYCEAE)1
Authors: Berges John A. , Harrison Paul J.
Published: August 2006

Light‐limited cultures of the marine diatom Thalassiosira pseudonana (Hustedt) Hasle and Heimdal (3H clone) were grown over a range of growth rates between 0.06 and 1.64 d−1. Variations in cell volume, cell quotas of carbon, nitrogen, and protein, and maximal activity of the enzyme nucleoside diphosphate kinase (NDPK) were measured and examined as a function of growth rate. NDPK from T. pseudonana showed Km values of 0.24 and 0.68 mM for thymidine 5′‐diphosphate and adenosine 5′‐triphosphate (ATP), respectively, which are similar to those found for NDPK from a variety of organisms, from bacteria to mammals. An apparent activation enthalpy of 3.52 kCal·mol−1 was determined from Arrhenius plots. No thermodynamic transition points were noted over a temperature range from 10° to 25°C. NDPK activity was significantly correlated with growth rate but not with cell volume, carbon, nitrogen, or protein; for interspecific comparisons, normalization of enzyme activity to cell number may be most meaningful. NDPK activity per cell versus growth rate followed a U‐shaped relationship, being relatively constant between 0.5 and 1.0 d−1 and rising at higher and lower growth rates. Over this range, enzyme activity may be regulated by substrate concentration (ATP or other nucleoside triphosphates) or by adenylate energy charge. At higher growth rates where energy charge and substrate concentrations are probably high, changes in enzyme concentration appear to be required. The reasons for a rise in enzyme activity at low growth rate is unclear. Simultaneous measurement of nucleoside di‐ and triphosphate levels alongside NDPK measurements may help clarify the relationship, but these preliminary experiments indicate that NDPK is of limited usefulness as an index of in situ growth rate.
INTRACELLULAR LOCALIZATION OF THE TASTE/ODOR METABOLITE 2‐METHYLISOBORNEOL IN OSCILLATORIA LIMOSA (CYANOPHYTA)1
Authors: Bafford Richard A. , Seagull Robert W. , Chung Si‐Yin , Millie David F.
Published: August 2006

The monoterpene derivative, 2‐methylisoborneol (MIB), is produced by many blue‐green algae and often is responsible for the “musty” taste/odor in aquaculturally raised finfish and potable water supplies. Although previous researchers have suggested that taste/odor metabolites are partitioned among cell constituents and that coregulation with pigment biosynthesis occurs, no structural evidence for these hypotheses exists. MIB was localized in cells of Oscillatoria limosa (Roth) Agardh at the ultrastructural level using standard gold‐labeled antibody techniques. There was no apparent relationship between age of the cells and MIB synthesis; cells that were and were not undergoing active division had similar amounts of MIB label. There was no consistent partitioning of MIB label within cells. However, occasionally, specific label was observed along photosynthetic lamellae, suggesting a potential linkage of MIB synthesis and/or binding to the pigment systems.
FLAVODOXIN EXPRESSION AS AN INDICATOR OF IRON LIMITATION IN MARINE DIATOMS1
Authors: Roche Julie La , Murray Helen , Orellana Mónica , Newton Jan
Published: August 2006

We have prevously shown that a marine chlorophyte expressed flavodoxin under iron limitation but not under other nutrient stress conditions. Here we use polyclonal antiserum raised against the diatom Phaeodactylum tricornutum Bohlin to show that a similar response is observed in this species. Using our antibody, western blotting techniques, and standard colorimetric detection (4‐chloro‐1‐naphthol), we can detect at least a 25–50‐fold increase in flavodoxin in iron‐depleted compared to iron‐replete cells. In iron‐limited batch cultures of P. tricornulum, flavodoxin accumulation was inversely proportional to growth rate and was not detectable in cultures containing initially more than 750 nm of iron. We demonstrated that the accumulation of flavodoxin under iron stress is widespread among marine diatoms and that it may be possible to use the presence or absence of flavodoxin in natural marine diatom assemblages to detect iron limitation. However, our polyclonal antisera appears to be specific for diatoms and did not cross‐react with Synechococcus sp., Micromonas pusilla (Butcher) Manton et Parke, Dunaliella tertiolecta Butcher, Chlorella sp., Emiliania huxleii (Lohm.) Hay et Parke, or Isochrysis galbana Parke. A reverse bioassay experiment was conducted with natural phytoplankton assemblages containing mainly diatoms from Long Island Sound and in shelf waters near Cape Hatteras, two areas not suspected to be iron‐limited. Although flavodoxin was not detected in situ in these areas, natural populations of diatoms driven into iron limitation expres.sed flavodoxin. Flavodoxin was detected in mats of the diatom Rhizosolenia castracanei Cleve collected from the Equatorial Pacific during a JGOFS cruise in 1992, consistent with the hypothesis that iron may be limiting in this high‐nutrient, low‐chlorophyll region.
ACCLIMATION OF THE PHOTOSYNTHETIC APPARATUS OF PALMARIA PALMATA (RHODOPHYTA) TO LIGHT QUALITIES THAT PREFERENTIALLY EXCITE PHOTOSYSTEM I OR PHOTOSYSTEM II1
Authors: Sagert Sigrid , Schubert Hendrik
Published: August 2006

Acclimation of the photosynthetic apparatus to light absorbed primarily by phycobilisomes (which transfer energy predominantly to photosystem II) or absorbed by chlorophyll a (mainly present in the antenna of photosystem I) was studied in the macroalga Palmaria palmata L. In addition, the influence of blue and yellow light, exciting chlorophyll a and phycobilisomes, respectively, ivas investigated. All results were compared to a white light control. Complementary chromatic adaptation in terms of an enhanced ratio of phycoerythrin to phycocyanin under green light conditions was observed. Red light (mainly absorbed by chlorophyll a) and green light (mainly absorbed by phycobilisomes) caused an increase of the antenna system, which was not preferentially excited. Yellow and blue light led to intermediate states comparable to each other and white light. Growth was reduced under all light qualities in comparison to white light, especially under conditions preferably exciting phycobilisomes (green light‐adapted algae had a 58% lower growth rate compared to white light‐adapted algae). Red and blue light‐adapted algae showed maximal photosynthetic capacity with white light excitation and significantly lower values with green light excitation. In contrast, green and yellow light‐adapted algae exhibited comparable photosynthetic capacities at all excitation wavelengths.

Low‐temperature fluorescence emission analysis showed an increase of photosystem II emission in red light‐adapted algae and a decrease in green light‐adapted algae. A small increase of photosystem I emission teas also found in green light‐adapted algae, but this was much less than the photosystem II emission increase observed in red light‐adapted algae (both compared to phycobilisome emission). Efficiency of energy transfer from phycobilisomes to photosystem II was higher in red than in green light‐adapted algae. The opposite was found for the energy transfer efficiency from phycobilisomes to photosystem I.

Zeaxanthin content increased in green and blue light‐adapted algae compared to red, white, and yellow light‐adapted algae.

Results are discussed in comparison to published data on unicellular red algae and cyanobacteria.
THE FLAGELLAR DEVELOPMENT CYCLE OF THE UNIFLAGELLATE PELAGOMONAS CALCEOLATA (PELAGOPHYCEAE)1
Authors: Heimann Kirsten , Andersen Robert A. , Wetherbee Richard
Published: August 2006

Vegetative cells of Pelagomonas calceolata Andersen & Saunders were confirmed to possess a reduced flagellar apparatus, consisting of a single basal body/flagellum that is not accompanied by either flagellar roots or a barren basal body. Just prior to division, the parental flagellum retracts (or is abscised) as two new basal bodies/flagella arise de novo. During cytokinesis the parental basal body segregates with a new basal body/flagellum, briefly producing a progeny cell typical of other known uniflagellates (i.e. containing a basal body/flagellum and accompanying barren basal body). The parental basal body then disintegrates or “transforms” out of existence, leaving both progeny cells with a single basal body/flagellum (i.e. neither progeny cell possesses any vestige of a mature flagellum/basal body). Pelagomonas calceolata belongs to a lineage of chromophyte algae characterized by having a reduced flagellar apparatus, but it is the only known species, not only in this lineage but among all eukaryotes, to have undergone the complete elimination of the mature flagellum /basal body.
THE FUCUS (PHAEOPHYCEAE) SPERM RECEPTOR FOR EGGS. II. ISOLATION OF A BINDING PROTEIN WHICH PARTIALLY ACTIVATES EGGS1
Authors: Wright Philip J. , Callow James A. , Green Jonathan R.
Published: August 2006

An in vitro binding assay involving egg plasma membrane vesicles (PMVs) of Fucus serratus L. and proteins contained in a KCl extract of sperm has been used to identify a sperm protein involved in egg binding. High‐performance gel filtration (HPGF) separated the sperm KCl extract into several major fractions, and a protein (apparent M, 60 kDa) was identified as being involved in binding to the egg PMVs. This protein ran on denaturing sodium dodecyl sulfate (SDS)gels with an apparent molecular weight of 27 kDa. This suggests that either the native form of the protein is a dimer or the molecular weight on HPGF is an artifact caused by high ionic strength buffer promoting hydrophobic interactions. When KCl‐sol‐uble proteins were separated by SDS‐polyacrylamide gel electrophoresis (PAGE), blotted onto nitrocellulose, and incubated with biotinylated egg PMVs, these bound to a band at 27 kDa, confirming the role of this protein. Addition of the Fucus sperm extract or HPGF fractions containing the binding protein to eggs in the absence of sperm induced the release of polysaccharides onto the egg cell surface. This labeling was patchy, in contrast to the uniform release of polysaccharides observed when sperm were added to eggs. The monoclonal antibody (MAb) FS17 was raised against the 27‐kDa sperm protein. It labeled the sperm body and both flagella by immunofluorescence, though the sperm had to he permeabilized to observe labeling, suggesting that the epitope recognized is not exposed at the cell surface. Addition of FS17 to the KCl extract in the binding assay reduced subsequent binding of egg PMVs. Removal of the 27‐kDa protein recognized by FS17 from the sperm extract prevented the binding of egg PMVs in the binding assay and the triggering of the patchy release of polysaccharides when added to eggs. Overall the results suggest that the 27‐kDa sperm protein is involved in binding to the egg plasma membrane and can trigger partial activation of the egg.
DIFFERENTIAL DISPLAY OF TISSUE‐SPECIFIC MESSENGER RNAs IN PORPHYRA PERFORATA (RHODOPHYTA) THALLUS1
Authors: Hong Yong‐Ki , Sohn Chul Hyun , Polne‐Fuller Miriam. , Gibor Aharon
Published: August 2006

Various tissue‐specific markers in differentiated regions of the Porphyra perforata J. Agardh thallus were identified by comparing the differential display derived from RNA polymerase chain reaction (RNA‐PCR) with arbitrary primers. Total RNA was extracted by the LiCl‐guanidinium method from six regions of differentiated thallus: male tissue, female tissue, patch tissue, vegetative dividing tissue, vegetative non‐dividing tissue, and holdfast tissue. First‐strand cDNA was synthesized by reverse transcription of total RNA with random hexamers and amplified by PCR with arbitrary primers. The morphologically distinct regions of the differentiated tissue revealed the presence of tissue‐specific differential display of gene expression.
MORPHOLOGY AND PAEDOGAMOUS SEXUAL REPRODUCTION IN CHLOROGONIUM CAPILLATUM SP. NOV. (VOLVOCALES, CHLOROPHYTA)1
Authors: Nozaki Hisayoshi , Watanabe Makoto M. , Aizawa Kenichi
Published: August 2006

Morphology and sexual reproduction in Chlorogonium capillatum Nozaki, Watanabe & Aizawa sp. nov. (Volvocales, Chlorophyta) originating from Miyatoko Mire, Japan, were studied under controlled laboratory conditions. Vegetative cells of this new species were fusiform with blunt anterior and posterior ends, and they had a massive parietal chloroplast and numerous contractile vacuoles distributed throughout the protoplast. Several to many pyrenoids were randomly distributed in the chloroplast, but they disappeared under the light microscope when grown photoheterotrophically. During asexual reproduction, the first division took place transversely without a preceding rotation of the parental protoplast. In sexual reproduction, the parental protoplast divided successively to form 32 or 64 small, biflagellate isogametes. After gametogenesis, the gametes did not escape from the parental cell (gametangial) wall, within which pairs of the adjoining gametes fused to form quadriflagellate zygotes. Such zygotes were then released from the parental cell wall and developed into hypnozygotes, which at maturity developed numerous thin spines or hairs on the zygote wall. On zygote germination, four biflagellate germ cells were released from the zygote wall separately. This type of gametic union, “paedogamy,” has not previously been described in the green algae except for Chlorococcum echinozygotum Starr. Chlorogonium capillatum can be clearly distinguished from other described species of Chlorogonium by its numerous contractile vacuoles and blunt anterior and posterior ends in vegetative cells as well as by its unique sexual reproduction, in which paedogamous conjugation occurs, and numerous thin spines or hairs that develop on the hypnozygote walls.