bluuebunny/crossref_metadata_2025 huggingface dataset:
Does stage‐based smoking cessation advice in pregnancy result in long‐term quitters? 18‐month postpartum follow‐up of a randomized controlled trial
Authors: Lawrence Terry , Aveyard Paul , Cheng K. K. , Griffin Carl , Johnson Carol , Croghan Emma
Published: December 2004

Aims To evaluate the effect on quitting smoking at 18 months postpartum of smoking cessation interventions based on the Transtheoretical Model (TTM) delivered in pregnancy compared to current standard care. It has been claimed that TTM‐based interventions will continue to create quitters after the end of the intervention period.

Design Cluster randomized trial.

Setting Antenatal clinics in general practices in the West Midlands, UK.

Participants A total of 918 pregnant smokers originally enrolled in the trial, of which 393 women were followed‐up at 18 months postpartum.

Interventions One hundred general practices were randomized into the three trial arms. Midwives in these practices delivered three interventions: A (standard care), B (TTM‐based self‐help manuals) and C (TTM‐based self‐help manuals plus sessions with an interactive computer program giving individualized smoking cessation advice).

Measurements Self‐reported continuous and point prevalence abstinence since pregnancy.

Findings When combined together, there was a slight and not significant benefit for both TTM arms compared to the control, with an odds ratio (OR) 95% confidence interval (CI) of 1.20 (0.29–4.88) for continuous abstinence. For point prevalence abstinence, the OR (95%CI) was 1.15 (0.66–2.03). Seven of the 54 (13%) women who had quit at the end of pregnancy were still quit 18 months later, and there was no evidence that the TTM‐based interventions were superior in preventing relapse.

Conclusions The TTM‐based interventions may have shown some evidence of a short‐term benefit for quitting in pregnancy but no benefit relative to standard care when followed‐up in the longer‐term.
Matching of treatment‐resistant heroin‐dependent patients to medical prescription of heroin or oral methadone treatment: results from two randomized controlled trials
Authors: Blanken Peter , Hendriks Vincent M. , Koeter Maarten W. J. , Van Ree Jan M. , Van Den Brink Wim
Published: December 2004

Aims  To investigate which baseline patient characteristics of treatment‐resistant heroin addicts differentially predicted treatment response to medical heroin prescription compared to standard methadone maintenance treatment.

Design  Two open‐label randomized controlled trials; pooled data.

Setting  Methadone maintenance programmes and heroin treatment centres in six cities in the Netherlands.

Participants  Four hundred and thirty heroin addicts.

Intervention  Methadone plus injectable heroin or methadone plus inhalable heroin compared to methadone alone prescribed over 12 months: heroin maximum 1000 mg per day, methadone maximum 150 mg per day.

Main outcome measure  Dichotomous, multi‐domain response index, including validated indicators of physical health, mental status and social functioning.

Findings  Data of the inhalable and injectable heroin trials were pooled. Intention‐to‐treat analysis showed that treatment with medically prescribed heroin plus methadone was significantly more effective (51.8% response) than standard methadone maintenance treatment (28.7%) (95% CI of response difference: 14.1–32.2%). Multivariate logistic regression analyses showed that only one of all baseline characteristics was predictive of a differential treatment effect: patients who had previously participated in abstinence‐orientated treatment responded significantly better to heroin‐assisted treatment than to methadone treatment (61% versus 24%), while patients without experience in abstinence‐orientated treatment did equally well in heroin‐assisted or methadone maintenance treatment (39% and 38%, respectively).

Conclusions  The effect of heroin‐assisted treatment is not dependent on clinical characteristics, with the exception of previous abstinence‐orientated treatment: medical prescription of heroin is most effective for those patients who have previously participated in abstinence‐orientated treatment.
Non‐medical use of prescription stimulants among US college students: prevalence and correlates from a national survey
Authors: McCabe Sean Esteban , Knight John R. , Teter Christian J. , Wechsler Henry
Published: December 2004

Aims  To examine the prevalence rates and correlates of non‐medical use of prescription stimulants (Ritalin, Dexedrine or Adderall) among US college students in terms of student and college characteristics.

Design  A self‐administered mail survey.

Setting  One hundred and nineteen nationally representative 4‐year colleges in the United States.

Participants  A representative sample of 10 904 randomly selected college students in 2001.

Measurements  Self‐reports of non‐medical use of prescription stimulants and other substance use behaviors.

Findings  The life‐time prevalence of non‐medical prescription stimulant use was 6.9%, past year prevalence was 4.1% and past month prevalence was 2.1%. Past year rates of non‐medical use ranged from zero to 25% at individual colleges. Multivariate regression analyses indicated non‐medical use was higher among college students who were male, white, members of fraternities and sororities and earned lower grade point averages. Rates were higher at colleges located in the north‐eastern region of the US and colleges with more competitive admission standards. Non‐medical prescription stimulant users were more likely to report use of alcohol, cigarettes, marijuana, ecstasy, cocaine and other risky behaviors.

Conclusions  The findings of the present study provide evidence that non‐medical use of prescription stimulants is more prevalent among particular subgroups of US college students and types of colleges. The non‐medical use of prescription stimulants represents a high‐risk behavior that should be monitored further and intervention efforts are needed to curb this form of drug use.
Electronic gaming machines: are they the ‘crack‐cocaine’ of gambling?
Authors: Dowling Nicki , Smith David , Thomas Trang
Published: December 2004

Background  There is a general view that electronic gaming is the most ‘addictive’ form of gambling, in that it contributes more to causing problem gambling than any other gambling activity. As such, electronic gaming machines have been referred to as the ‘crack‐cocaine’ of gambling. While this analogy has popular appeal, it is only recently that the scientific community has begun to investigate its validity. In line with the belief that electronic gambling has a higher ‘addictive’ potential than other forms of gambling, research has also begun to focus on identifying the characteristics of gaming machines that may be associated with problem gambling behaviour.

Aims and methods  This paper will review the different types of modern electronic gaming machines, and will use the introduction of gaming machines to Australia to examine the association between electronic gaming and problem gambling, with particular reference to the characteristics of modern electronic gaming machines.

Findings and conclusions  Despite overwhelming acceptance that gaming machines are associated with the highest level of problem gambling, the empirical literature provides inconclusive evidence to support the analogy likening electronic gaming to ‘crack‐cocaine’. Rigorous and systematic evaluation is required to establish definitively the absolute ‘addictive’ potential of gaming machines and the degree to which machine characteristics influence the development and maintenance of problem gambling behaviour.
Ultrase MT12 and Ultrase MT20 in the treatment of exocrine pancreatic insufficiency in cystic fibrosis: safety and efficacy
Authors: Konstan M. W. , Stern R. C. , Trout J. R. , Sherman J. M. , Eigen H. , Wagener J. S. , Duggan C. , Wohl M. E. B. , Colin P.
Published: December 2004

Background : Cystic fibrosis causes exocrine pancreatic insufficiency, leading to malabsorption. Supplemental pancreatic enzyme therapy alleviates the concomitant malnutrition experienced by cystic fibrosis patients. It is recognized that patients experience variations in clinical response to different brands of enzymes. This has prompted the US Food and Drug Administration to require that enzyme supplements be subjected to New Drug Applications.

Aim : To investigate the safety and efficacy of supplemental pancreatic enzyme therapy in cystic fibrosis subjects.

Methods : We compared two doses of one formulation of enteric‐coated pancreatic enzymes: Ultrase MT12 (12 000 lipase units per capsule) and Ultrase MT20 (20 000 lipase units per capsule), to placebo in two separate safety and efficacy studies.

Results : Mean total fat, protein and carbohydrate intake did not differ significantly between the groups. A significant difference in both fat and protein absorption occurred with the enzyme therapy groups. The Ultrase MT12 and Ultrase MT20 groups experienced a mean fat and protein absorption 79.4% and 83.8%, and 87.3% and 88.6%, respectively. No adverse events related to study drug were reported.

Conclusions : This study further supports the use of enzymes to treat pancreatic insufficiency in cystic fibrosis. Excellent fat and protein absorption was achieved with minimal adverse events and safe doses.
A prospective assessment of cytomegalovirus infection in active inflammatory bowel disease
Authors: de Saussure P. , Lavergne‐Slove A. , Mazeron M.‐C. , Alain S. , Matuchansky C. , Bouhnik Y.
Published: December 2004

Background:  The prevalence and clinical significance of cytomegalovirus infection is reportedly high in patients with refractory inflammatory bowel disease but is unknown in unselected patients with active disease.

Methods:  In patients admitted for active inflammatory bowel disease, we prospectively studied the presence and significance of cytomegalovirus infection using anti‐cytomegalovirus antibodies, cytomegalovirus viraemia and antigenaemia and cytomegalovirus inclusions and cytomegalovirus immunochemistry staining in ileocolonic biopsies.

Results:  A total of 64 patients were included (ulcerative colitis, n = 23; Crohn's disease, n = 41), 18 of whom had been on high‐dose oral steroids and 11 on immunosuppressants. Anti‐cytomegalovirus IgG and IgM were positive in 42 (66%) and 3 (5%) patients respectively. Blood or urine cytomegalovirus replication markers were found in 4 (6%) patients, all of whom had ulcerative colitis. Three patients had cytomegalovirus viraemia and received anti‐viral treatment with ganciclovir. Only one of these patients had cytomegalovirus antigenaemia and also associated biopsy‐proven cytomegalovirus colitis, probably as a primary cytomegalovirus infection. This patient is the only one who benefitted from anti‐viral therapy.

Conclusions:  Cytomegalovirus infection is infrequent in in‐patients with active inflammatory bowel disease. Systematic search of cytomegalovirus replication markers should not be performed. Isolated viraemia without associated antigenaemia or direct demonstration of cytomegalovirus in ileocolonic biopsies does not warrant anti‐viral therapy.
Intestinal permeability in patients with irritable bowel syndrome after a waterborne outbreak of acute gastroenteritis in Walkerton, Ontario
Authors: Marshall J. K. , Thabane M. , Garg A. X. , Clark W. , Meddings J. , Collins S. M. ,   for the WEL Investigators
Published: December 2004

Background : Post‐infectious irritable bowel syndrome is a common clinical phenomenon of uncertain aetiology.

Aim : To test the association between intestinal permeability and irritable bowel syndrome symptoms 2 years after a large waterborne outbreak of bacterial gastroenteritis.

Methods : Consecutive adults with Rome I irritable bowel syndrome and controls without irritable bowel syndrome attending a community clinic were enrolled. Intestinal permeability was measured as the ratio of fractional urinary excretions of lactulose and mannitol, and compared among cases vs. controls and predictors of abnormal intestinal permeability were assessed.

Results : A total of 218 subjects (132 irritable bowel syndrome cases and 86 non‐irritable bowel syndrome controls) completed the study protocol. About 27 (12%) had been diagnosed with the irritable bowel syndrome before the outbreak and 115 (53%) had been ill during the outbreak. Lactulose–mannitol ratios were increased among cases vs. controls (Mann–Whitney mean rank 118.8 vs. 95.3, P = 0.007), and cases were more likely to have a ratio >0.020 (P = 0.007). Among cases, those with increased intestinal permeability were more likely to report increased stool frequency. Both irritable bowel syndrome symptoms and male gender, but not diarrhoeal illness during the outbreak, were significant predictors of abnormal permeability.

Conclusions : Irritable bowel syndrome symptoms are associated with a subtle increase in intestinal permeability irrespective of prior gastroenteritis. This may improve understanding of the aetiology of both sporadic and post‐infectious irritable bowel syndrome.
Intravenous CDP870, a PEGylated Fab′ fragment of a humanized antitumour necrosis factor antibody, in patients with moderate‐to‐severe Crohn's disease: an exploratory study
Authors: Winter T. A. , Wright J. , Ghosh S. , Jahnsen J. , Innes A. , Round P.
Published: December 2004

Background : CDP870 is a PEGylated Fab′ fragment of a humanized monoclonal antibody that neutralizes tumour necrosis factor‐α.

Aim : To evaluate the safety and efficacy of a single intravenous dose of CDP870 or placebo over a 12‐week period in patients with moderate‐to‐severe Crohn's disease.

Methods : Ninety‐two adult patients with Crohn's disease (Crohn's Disease Activity Index: 220–450 points) were randomized to receive CDP870 [1.25 (n = 2), 5 (n =26), 10 (n = 17) or 20 mg/kg (n = 23)] or placebo (n = 24). Crohn's Disease Activity Index scores were determined at weeks 0, 2, 4, 8 and 12. The primary end‐point was the percentage of patients achieving clinical response [i.e. a decrease in Crohn's Disease Activity Index score ≥ 100 points or remission (Crohn's Disease Activity Index score: ≤150 points)] at week 4 in the intent‐to‐treat population.

Results : The percentage of patients achieving the primary end‐point was comparable across all treatment groups (56.0%, 60.0%, 58.8% and 47.8% for placebo, CDP870 5, 10 and 20 mg/kg, respectively). The remission rate at week 2 was 47.1% with CDP870 10 mg/kg vs. 16.0% for placebo (P = 0.041). All treatments were well‐tolerated: adverse events, reported by 43 patients treated with CDP870 and 15 patients treated with placebo, were mainly mild‐to‐moderate in intensity. There were no infusion reactions.

Conclusions : A single intravenous dose of CDP870 was well‐tolerated by patients with Crohn's disease. While no statistically significant difference in clinical response rates between CDP870 and placebo was observed, clinical benefit in terms of remission was demonstrated.
Granulocyteaphaeresis in steroid‐dependent inflammatory bowel disease: a prospective, open, pilot study
Authors: Domènech E. , Hinojosa J. , Esteve‐Comas M. , Gomollón F. , Herrera J. M. , Bastida G. , Obrador A. , Ruiz R. , Saro C. , Gassull M. A. ,   for the Spanish Group for the Study of Crohn's Disease and Ulcerative Colitis (GETECCU)
Published: December 2004

Background : Uncontrolled studies suggest that granulocyteaphaeresis might be useful in the management of active ulcerative colitis.

Aim : To assess the efficacy of granulocyteaphaeresis treatment in active steroid‐dependent inflammatory bowel disease.

Methods : We conducted a multicentre, prospective, open, pilot study in patients with steroid‐dependent inflammatory bowel disease. All patients were started on 60 mg/day of prednisone; after 1 week, a five‐session programme of granulocyteaphaeresis (once per week) was started. The steroid dose was tapered weekly if there was clinical improvement. Remission was defined as an inactive clinical activity index together with complete withdrawal of steroids at week 6. The patients were followed up for at least 6 months or until disease relapse.

Results : Twenty‐six patients (14 ulcerative colitis, 12 Crohn's disease) were included. More than a half had been previously treated with immunomodulators. Remission was achieved in 62 and 70% of ulcerative colitis and Crohn's disease, respectively. During a median follow‐up of 12.6 months, six of eight ulcerative colitis patients maintained their clinical remission; however, only one Crohn's disease patient remained in remission after the first 6 months of follow‐up.

Conclusions : Granulocyteaphaeresis is a safe treatment option in inflammatory bowel disease. A five‐session programme of granulocyteaphaeresis seems to be efficient in the treatment of steroid‐dependent ulcerative colitis, but not in Crohn's disease.
Genotype distribution of Candida albicans isolates by 25S intron analysis with regard to invasiveness
Authors: Karahan Z. C. , Güriz H. , Ağırbaşlı H. , Balaban N. , Göçmen J. S. , Aysev D. , Akar N.
Published: December 2004

The aim of this study was to genotype Candida albicans strains isolated from patients with invasive and non‐invasive deep‐seated infections. For this purpose, 301 C. albicans isolates (81 invasive and 220 non‐invasive) were genotyped by using specific PCR primers designed to span the transposable group I intron of the 25S rDNA gene. Fifty‐three of the 81 invasive isolates were genotype A (65.4%), eight were genotype B (9.9%) and 20 were genotype C (24.7%), while 98 of the 220 non‐invasive isolates were genotype A (44.6%), 46 were genotype B (20.9%) and 76 were genotype C (34.5%). Genotype A was more prevalent among invasive isolates and genotypes B and C were more prevalent among non‐invasive isolates (P = 0.0046). Genotypes D and E which represent C. dubliniensis were not found. These results indicate that there may be a relationship between C. albicans genotypes and invasiveness; genotype A being more invasive than others. The presence or absence of the transposable group I intron in the 25S rDNA gene may be important in determining the invasiveness of C. albicans.
Bullous tinea pedis in two children
Authors: Neri I. , Piraccini B. M. , Guareschi E. , Patrizi A.
Published: December 2004

Tinea pedis is a dermatophytic infection with a high prevalence in adults and also occasionally observed in children. We report here two cases of bullous tinea pedis, one due to Trichophyton rubrum in a 6‐year‐old child and the second due to T. interdigitale in a 10‐year‐old child. We suggest that, despite the low prevalence of this infection in childhood, a potassium hydroxide test and a culture for fungi should always be performed when a child is examined for an inflammatory eruption of the feet.
Invasive aspergillosis with polyarthritis
Authors: Mekan S. F. , Saeed O. , Khan J. A.
Published: December 2004

We report a case of septic arthritis of multiple joints in an 18‐year‐old male caused by Aspergillus fumigatus. His initial presentation was of low‐grade fever followed by involvement of both knee and ankle joints. Later, there was also involvement of metacarpophalangeal joints. Diagnosis was based on biopsy and culture of the skin and joint lesions. The symptoms resolved readily under administration of itraconazole. We recommend that clinicians should be alerted of potential fungal etiology in cases of fever and chronic arthritis, which is unresponsive to conventional medical therapy.
In vitro evaluation of griseofulvin against clinical isolates of dermatophytes from Isfahan
Authors: Chadeganipour Mostafa , Nilipour Shahi , Havaei Asghar
Published: December 2004

Fifty dermatophyte isolates, recently obtained from clinical materials, belonging to Trichophyton mentagrophytes, T. verrucosum, Microsporum canis and Epidermophyton floccosum were examined for their susceptibility to griseofulvin. The minimum inhibitory concentration (MIC) values were obtained using the modified microdilution method. All 100% tested isolates had MIC geometric mean at a concentration between 0.43 and 0.95 μg ml−1 The MIC90s and MIC50s were 8 μg ml−1 and <0.25–1 μg ml−1 respectively. From all isolates, 12% including three T. verrucosum, one M. canis and two T. mentagrophytes isolates had MIC values out of the standardized range, therefore, they were considered as relatively griseofulvin‐resistant. At least some of the isolates tested might be difficult to eradicate in clinical terms with griseofulvin treatment in Isfahan.
Competitive interactions between retinal ganglion axons for tectal targets explain plasticity of retinotectal projection in the servomechanism model of retinotectal mapping
Authors: Honda Hisao
Published: December 2004

The mechanism of topographic mapping of retinal ganglion cells to the midbrain was previously elucidated by the servomechanism model, which is based on the fact that cells expressing Eph‐receptors respond specifically to surface expressing membrane‐bound ephrin‐ligands at a critical level. The retina has increased nasal‐to‐temporal gradient of Eph receptor‐density, and the optic tectum/superior colliculus has increased rostral‐to‐caudal gradient of membrane‐bound ephrin‐ligand. An axon from the retina has an identification tag of a certain level of Eph‐receptor density depending on its retinal position, and adheres to the site on the tectum/superior colliculus expressing ephrin‐ligands at a critical ligand‐density level. The servomechanism model rigidly defines positions of axon terminals on the midbrain. However, optic nerve regeneration experiments combined with halved retina or tectum show a plastic or flexible mapping (expansion, compression and transposition of tectal projections). To reconcile the discrepancy between the rigid model and the plastic behavior, competition between retinal axon terminals for a target site was introduced to the servomechanism. The servomechanism/competition model succeeded in computer simulations of the plastic mapping of retinal axons on the tectum. Recent experiments of upregulated ligand‐density on the tectum during nerve regeneration and the role of axonal competition are discussed.
Targeted disruption of the murine Plag1 proto‐oncogene causes growth retardation and reduced fertility
Authors: Hensen Karen , Braem Caroline , Declercq Jeroen , Van Dyck Frederik , Dewerchin Mieke , Fiette Laurence , Denef Carl , Van de Ven Wim J. M.
Published: December 2004

The pleomorphic adenoma gene 1 (Plag1) proto‐oncogene encodes a transcription factor and is implicated in human tumorigenesis via ectopic overexpression. No information is available about its developmental role. To address this, a Plag1–/– mouse strain was generated and it appears that Plag1‐deficient mice are viable. No anatomical differences are obvious at birth, except that the weight of Plag1–/– mice is significantly lower in comparison to control litter mates. This early growth retardation is maintained throughout adult life with proportionally smaller organs except for the disproportionally small seminal vesicles and ventral prostate; however, plasma testosterone levels in males were not affected. Furthermore, fertility of both male and female Plag1–/– is reduced. Northern blot analysis revealed that Plag1 is developmentally regulated with high overall fetal expression levels, which drop after birth. Furthermore, Plag1 is differentially expressed and is readily detectable in the reproductive organs and pituitary. Expression of growth regulatory Igf2, a known target gene of Plag1 in tumorigenesis, was not affected in Plag1–/– embryos and pups. The general morphology and histology of the size‐reduced pituitaries was not affected. Our results establish that Plag1 disruption in mouse differentially affects pre‐ and postnatal growth and development of organs, with reproductive repercussions.
INVERTEBRATE‐MEDIATED NUTRIENT LOADING INCREASES GROWTH OF AN INTERTIDAL MACROALGA1
Authors: Bracken Matthew E. S.
Published: December 2004

Even in nitrogen‐replete ecosystems, microhabitats exist where local‐scale nutrient limitation occurs. For example, coastal waters of the northeastern Pacific Ocean are characterized by high nitrate concentrations associated with upwelling. However, macroalgae living in high‐zone tide pools on adjacent rocky shores are isolated from this upwelled nitrate for extended periods of time, leading to nutrient limitation. When high‐intertidal pools are isolated during low tide, invertebrate‐excreted ammonium accumulates, providing a potential nitrogen source for macroalgae. I quantified the influence of mussels (Mytilus californianus Conrad) on ammonium accumulation rates in tide pools. I then evaluated the effects of ammonium loading by mussels on nitrogen assimilation and growth rates of Odonthalia floccosa (Esp.) Falkenb., a common red algal inhabitant of pools on northeastern Pacific rocky shores. Odonthalia was grown in artificial tide pool mesocosms in the presence and absence of mussels. Mesocosms were subjected to a simulated tidal cycle mimicking emersion and immersion patterns of high‐intertidal pools on the central Oregon coast. In the presence of mussels, ammonium accumulated more quickly in the mesocosms, resulting in increased rates of nitrogen assimilation into algal tissues. These increased nitrogen assimilation rates were primarily associated with higher growth rates. In mesocosms containing mussels, Odonthalia individuals added 41% more biomass than in mesocosms without mussels. This direct positive effect of mussels on macroalgal biomass represents an often overlooked interaction between macroalgae and invertebrates. In nutrient‐limited microhabitats, such as high‐intertidal pools, invertebrate‐excreted ammonium is likely an important local‐scale contributor to macroalgal productivity.
THE INVASIVE GENUS ASPARAGOPSIS (BONNEMAISONIACEAE, RHODOPHYTA): MOLECULAR SYSTEMATICS, MORPHOLOGY, AND ECOPHYSIOLOGY OF FALKENBERGIA ISOLATES1
Authors: Chualáin Fionnuala Ní , Maggs Christine A. , Saunders Gary W. , Guiry Michael D.
Published: December 2004

The genus Asparagopsis was studied using 25 Falkenbergia tetrasporophyte strains collected worldwide. Plastid (cp) DNA RFLP revealed three groups of isolates, which differed in their small subunit rRNA gene sequences, temperature responses, and tetrasporophytic morphology (cell sizes). Strains from Australia, Chile, San Diego, and Atlantic and Mediterranean Europe were identifiable as A. armata Harvey, the gametophyte of which has distinctive barbed spines. This species is believed to be endemic to cold‐temperate waters of Australia and New Zealand and was introduced into Europe in the 1920s. All isolates showed identical cpDNA RFLPs, consistent with a recent introduction from Australia. Asparagopsis taxiformis (Delile) Trevisan, the type and only other recognized species, which lacks spines, is cosmopolitan in warm‐temperate to tropical waters. Two clades differed morphologically and ecophysiologically and in the future could be recognized as sibling species or subspecies. A Pacific/Italian clade had 4–8° C lower survival minima and included a genetically distinct apomictic isolate from Western Australia that corresponded to the form of A. taxiformis originally described as A. sanfordiana Harvey. The second clade, from the Caribbean and the Canaries, is stenothermal (subtropical to tropical) with some ecotypic variation. The genus Asparagopsis consists of two or possibly three species, but a definitive taxonomic treatment of the two A. taxiformis clades requires study of field‐collected gametophytes.
SINGLE‐CELL PULSE AMPLITUDE MODULATION FLUORESCENCE MEASUREMENTS OF THE GIANT DIATOM ETHMODISCUS (BACILLARIOPHYCEAE)1
Authors: Villareal Tracy A.
Published: December 2004

Diurnal changes in effective yield (ΔF:Fm′), rapid light curves (RLCs), and induction/dark recovery time series were measured on individual cells of the giant diatom Ethmodiscus Castracane using active fluorescence (pulse amplitude modulation fluorometry). Unlike the co‐occurring diatom Hemiaulus and bulk phytoplankton, there was no observable diurnal down‐regulation of yield or relative electron transport rates in Ethmodiscus. Yields were constant at or near maximum values (0.7–0.8). Increases in ΔF:Fm′ during the initial actinic levels are consistent with dark nonphotochemical quenching mechanisms. Sustained actinic illumination (660 μmol photon·m−2·s−1) resulted in a ΔF:Fm′ of 0.2–0.3, but rapid recovery to near‐maximum values occurred in subsequent dark periods. Such recovery occurred even after exposure to full sunlight for 28 min, but not at 60 min. Thus, the lack of diurnal down‐regulation in Ethmodiscus is apparent, not real, and is an artifact of the time scale of sample extraction from net tows. These positively buoyant cells showed no evidence of routine photodamage, probably due to mixing and reduction in the average light exposure. The general patterns seen in RLCs from light‐and dark‐adapted higher plants are significantly different from those observed in Ethmodiscus. These results suggest that active fluorescence characteristics require careful examination to differentiate habitat‐ and taxon‐specific characteristics from light‐history effects. It is unclear whether the rapid recovery seen in Ethmodiscus is unique. The differences seen between Hemiaulus and Ethmodiscus from the same samples suggest that changes in community yield values measured in countertop systems could be the result of species replacement in addition to experimental or environmental perturbations.
CAROTENOID COMPOSITIONS OF CLADOPHORA BALLS (AEGAGROPILA LINNAEI) AND SOME MEMBERS OF THE CLADOPHORALES (ULVOPHYCEAE, CHLOROPHYTA): THEIR TAXONOMIC AND EVOLUTIONARY IMPLICATION1
Authors: Yoshii Yukie , Hanyuda Takeaki , Wakana Isamu , Miyaji Kazuyuki , Arai Shogo , Ueda Kunihiko , Inouye Isao
Published: December 2004

Photosynthetic pigments were analyzed by HPLC for 27 samples of the Cladophorales (Ulvophyceae, Chlorophyta). The carotenoid compositions of the examined algae were classified into three types based on the final compound of biosynthesis of the α‐carotene branch: lutein type, characterized by containing lutein as a major carotenoid and lacking loroxanthin and siphonaxanthin; loroxanthin type, characterized by containing loroxanthin and lacking siphonaxanthin; and siphonaxanthin type, characterized by containing siphonaxanthin. We constructed molecular phylogenetic tree of the species examined in the present study using 18S rRNA gene sequences and mapped the carotenoid types of the species onto the tree. The molecular phylogenetic analysis divided the Cladophorales into two major clades, clade 1 and Aegagropila‐clade (clade 2), and divided clade 1 into subclade 1‐1 and subclade 1‐2. All the examined species positioned in the Aegagropila‐clade and those of the subclade 1‐1 belonged to the loroxanthin type, whereas both lutein type and siphonaxanthin type appeared only in the subclade 1‐2. The clades delineated by molecular phylogenetic analysis were congruent with distribution of the carotenoid types, indicating that the carotenoid types are of taxonomic significance in the Cladophorales. Considering the distribution pattern of these carotenoid types and minimum state changes in the Cladophorales, we concluded that the loroxanthin type was the primitive (plesiomorphic) state and the siphonaxanthin type and lutein type appeared in the subclade 1‐2 as advanced (apomorphic) state within this order and suggested that the cladophoralean siphonaxanthin type would have been secondarily acquired.
INTENSE GRAZING AND PREY‐DEPENDENT GROWTH OF PFIESTERIA PISCICIDA (DINOPHYCEAE)1
Authors: Lin Senjie , Mulholland Margaret R. , Zhang Huan , Feinstein Timothy N. , Jochem Frank J. , Carpenter Edward J.
Published: December 2004

Grazing and growth of Pfiesteria piscicida (Pfiest) were investigated using batch and cyclostat cultures with Rhodomonas sp. (Rhod) as prey. Observed maximum growth rates (1.4 d−1) and population densities (2 × 105 cells·mL−1) corresponded to values predicted by Monod functions (1.76 d−1; 1.4 × 105 cells·mL−1). In batch cultures under a range of prey‐to‐predator ratios (0.1:1 to 180:1) and prey concentrations (1000–71,000 cells·mL−1), Rhodomonas sp. was always depleted rapidly and P. piscicida concentrations increased briefly. The rate of Rhodomonas sp. depletion and the magnitude of P. piscicida population maxima depended on the prey‐to‐predator ratio and prey concentration. Starvation resulted in cell cycle arrest at G1 and G2+M and ultimately the demise of both P. piscicida and Rhodomonas sp. populations, demonstrating the dependence of P. piscicida on the supply of appropriate prey. The depletion of Rhodomonas sp. populations could be attributed directly to grazing, because P. piscicida did not exert detectable inhibitory effects on the growth of Rhodomonas sp. but grazed intensely, with maximum grazing rates>10 Rhod·Pfiest−1·d−1 and with no apparent threshold prey abundance for grazing. The results suggest that 1) the abundance of appropriate prey may be an important factor regulating P. piscicida abundance in nature, 2) P. piscicida may control prey population, and 3) high growth and grazing potentials of P. piscicida along with cell cycle arrest may confer survival advantages.
FIRST EVIDENCE OF PALYTOXIN ANALOGUES FROM ANOSTREOPSIS MASCARENENSIS(DINOPHYCEAE) BENTHIC BLOOM IN SOUTHWESTERN INDIAN OCEAN1
Authors: Lenoir Séverine , Ten‐Hage Loïc , Turquet Jean , Quod Jean‐Pascal , Bernard Cécile , Hennion Marie‐Claire
Published: December 2004

Benthic dinoflagellates of the genusOstreopsisSchmidt are common in tropical and subtropical water, and some species produce toxins potentially involved in human intoxication events. A benthic bloom ofOstreopsis mascarenensisQuod was observed near Rodrigues Island during a survey of benthic dinoflagellates in the southwestern Indian Ocean. The morphology ofO. mascarenensiswas studied by LM and SEM. Preliminary screening of a crude extract of anO.mascarenensisbloom revealed neurotoxicity in mice similar to that induced by palytoxin. After partition of the crude extract, the highest toxicity was retained in the butanol‐soluble fraction, which retained hemolytic activity suggestive of palytoxin analogues. Two new toxins, mascarenotoxin‐A and ‐B, were resolved from this fraction by HPLC coupled to a diode array detector. The closed mass spectrum profile and fragmentation pattern obtained by advanced nano–electrospray ionization quadrupole time‐of‐flight mass spectrometry between purified toxins and a reference palytoxin confirmed the mascarenotoxins as palytoxin analogues. These results were confirmed by tandem mass spectrometry with the identification of specific fragment ionm/z327. An on‐line liquid chromatography protocol coupled to tandem mass spectrometry was developed for detection of these palytoxin analogues. The present study describes the first purification, chemical, and toxicological characterization of new palytoxin analogues isolated from a benthic bloom ofO. mascarenensis. These results suggest thatO. mascarenensis, which is largely distributed in the southwestern Indian Ocean, could be a source of palytoxin poisoning in this tropical area.
MORPHOLOGICAL CHANGES DURING AKINETE GERMINATION IN CYLINDROSPERMOPSIS RACIBORSKII (NOSTOCALES, CYANOBACTERIA)1
Authors: Moore David , McGregor Glenn B. , Shaw Glen
Published: December 2004

The occurrence of the cyanobacterium Cylindrospermopsis raciborskii (Woloszynska) Seenayya and Subba Raju is a global water quality issue. The misidentification of C. raciborskii in the past is a major concern for water quality users, considering the reported cases of human and livestock poisonings associated with the cyanobacterium. Many of the available taxonomic descriptions for this species provide little or no detail of the morphology of early developmental phases that may assist with identification. Therefore, typifying the morphological changes throughout the entire life cycle for such a species requires urgent attention. In this study, five distinct morphological phases identified using a new culturing technique are reported for the process of akinete germination in C. raciborskii. Before the terminal emergence of three to four cell germlings through a ruptured akinete envelope (phase 3), mature akinetes (phase 1) elongated and the endospore separated from the akinete envelope (phase 2). After the association with the envelope was lost, four‐cell germlings (phase 4a) matured into young trichomes of more than four cells (phase 4b). Throughout the process of germination, internal granular structures decreased in size and were irregular in shape in germlings and young trichomes. The culturing technique, which used a Sedgwick‐Rafter cell, was successful in its application but was limiting in that the development of young trichomes after phase 4b could not be monitored.
DETERMINING THE AFFINITIES OF SALT MARSH FUCOIDS USING MICROSATELLITE MARKERS: EVIDENCE OF HYBRIDIZATION AND INTROGRESSION BETWEEN TWO SPECIES OFFUCUS(PHAEOPHYTA) IN A MAINE ESTUARY1
Authors: Wallace Aaron L. , Klein Anita S. , Mathieson Arthur C.
Published: December 2004

The high degree of morphological plasticity displayed by species of the brown algal genusFucusL. is well documented. Such variation is especially pronounced for those estuarine taxa lacking holdfasts (termed ecads) that often bear little resemblance to the attached species from which they are derived. To better understand the systematics of salt marsh fucoids, we developed a suite of four microsatellite‐containing loci capable of distinguishing betweenF. vesiculosusL. andF. spiralisL. The genetic markers were used to determine the relationships of the fucoid ecadsF. vesiculosusecadvolubilis(Hudson) Turner and a muscoides‐likeFucusin the Brave Boat Harbor (ME, USA) estuary. Ecad populations had 2‐ to 3‐fold higher levels of heterozygosity than attached populations ofF. vesiculosusandF. spiralis. Further, ecads were “intermediate” betweenF. vesiculosusandF. spiralisin their allele frequencies and genotype composition. Our data indicate that populations of muscoides‐likeFucusin Brave Boat Harbor mainly consist of F1hybrids betweenF. vesiculosusandF. spiralis, whereasF. vesiculosusecadvolubilismay arise through backcrosses betweenF. vesiculosusand other fertile hybrids. Finally, our data support the hypothesis that introgression has occurred between attached populations ofF. vesiculosusandF. spiralis.
STRUCTURAL CHARACTERIZATION OF THE TERMINAL DOMAINS OF LINEAR PLASMID‐LIKE DNA FROM THE GREEN ALGA ERNODESMIS (CHLOROPHYTA)1
Authors: La Claire John W. , Wang Jingshan
Published: December 2004

Terminal regions of linear plasmid‐like DNA molecules from chloroplasts of the green alga Ernodesmis verticillata (Kützing) Børgesen were cloned and structurally characterized. Phosphorylation experiments with polynucleotide kinase indicated the presence of a 5′‐phosphate, but the data did not reveal any protective protein(s) at the 5′ end. To characterize the 3′ end of these molecules, homopolymer‐ (poly(G)‐) tailed molecules were annealed to and cloned into a linearized vector that was poly(C) tailed with terminal deoxynucleotidyl transferase. Sequencing analyses verified the heterogeneous nature of the molecules. Two distinct clones displayed extensive terminal inverted repeats (TIRs) at the 3′ end (94 and 433 nt). Shorter TIRs (3–6 nt) were identified at the 3′ end of most clones, which may serve to protect the ends. In fact, exonuclease III and λ exonuclease digested the plasmid‐like DNAs only after heat denaturation, signifying that conformational changes due to such treatment potentially make the 3′ and 5′ ends (respectively) susceptible to degradation. Multiple tandem and direct repeats were evident near the 3′ ends. A consensus sequence of 18+ nt was discovered in nearly every clone opposite the poly(G) tail, suggesting that this sequence has structural and/or functional significance. Pair‐wise sequence comparisons and the presence of repeats indicated that these novel molecules may be highly recombinant.
Repetitive Intraoperative Dislocation During Transvenous Left Ventricular Lead Implantation:
Authors: DE COCK CAREL C. , JESSURUN EMILE R. , ALLAART C.A. , VISSER CEES A.
Published: December 2004

Dislocation of the transvenous left ventricular lead has been reported in a substantial number of patients selected for cardiac resynchronization therapy. We describe a novel technique using a retained guidewire in patients with repetitive intraoperative dislocation to stabilize the lead in its final position. Pacing and sensing parameters between patients in whom the retained guidewire technique was used (n = 6) were not significantly different as compared to the group of patients (n = 67) without this technique during a 6‐month follow‐up. No dislocations were observed in the group of patients with the retained guidewire technique and fluoroscopic evaluation did not reveal (minor) dislocation. This technique might be considered for patients with repetitive intraoperative left ventricular lead dislocation.
Time Course and Predictors of Autonomic Dysfunction After Ablation of the Slow Atrioventricular Nodal Pathway
Authors: MARKOWITZ STEVEN M. , CHRISTINI DAVID J. , STEIN KENNETH M. , MITTAL SUNEET , IWAI SEI , SLOTWINER DAVID J. , LERMAN BRUCE B.
Published: December 2004

Withdrawal of parasympathetic tone has been reported after ablation in the posteroseptal right atrium and has been attributed to injury of vagal efferent fibers. The purpose of this study was to assess the time course and predictors of autonomic dysfunction after slow pathway ablation. In 30 patients with AV nodal reentrant tachycardia, time‐ and frequency‐domain measures of heart rate variability (HRV) were measured before, 30 minutes after, and 1 day after slow pathway ablation. There were significant reductions in mean RR interval (724 ± 163 vs 836 ± 164 ms, P < 0.05), SD of RR intervals (29 ± 17 vs 40 ± 18 ms, P < 0.05), root mean squared difference (15 ± 8 vs 29 ± 17 ms, P < 0.05), and high frequency power (4.1 ± 0.4 vs 4.5 ± 0.6 log10ms2, P < 0.05) 30 minutes after ablation. However, these parameters returned to baseline 1 day after ablation. Multivariate regression identified isoproterenol dose during the diagnostic study (P = 0.02) and radiofrequency duration (P = 0.02) as statistically significant predictors of heart rate change (R2= 0.45). These findings suggest that changes in autonomic tone after ablation in the posteroseptal right atrium are transitory and resolve within 1 day of the procedure. These short‐term changes may be related to procedural variables rather than direct injury to vagal efferent fibers.
Left Ventricular Malposition of Pacemaker Lead in Chagas' Disease
Authors: CHUN JULIAN K.R. , BODE FRANK , WIEGAND UWE K.H.
Published: December 2004

A 52‐year‐old Argentinian woman presented with third‐degree AV block due to seropositive chronic stage of Chagas' disease. Subsequently, a DDD pacemaker was implanted. Interestingly, a postoperative chest X ray suggested left ventricular lead misplacement, an ECG showed a paced RBBB. Echocardiography confirmed suspected lead malposition in the left ventricle with perforation of a large aneurysm of the interatrial septum that might be related to Chagas' disease. The ventricular lead was successfully repositioned in the right ventricle. Therefore, to avoid lead malposition in Chagas' disease structural cardiac defects should always be ruled out before operation. If a paced RBBB indicates malposition, different fluoroscopic projections should be used to verify lead position.
A Rare Cause of Complete Heart Block After Transdermal Botanical Treatment for Psoriasis
Authors: WOJTYNA WOJCIECH , ENSELEIT FRANK
Published: December 2004

We report the case of a 59‐year‐old man with a new 3° AV block with a history of psoriasis. After implantation of a definitive DDDR pacemaker, the patient reported a transdermal self‐medication with an extract of Nerium oleander for the treatment of his psoriasis. The pharmacological, epidemiological, and clinical features are discussed in brief.
The effects of nutrient variation and age on the resistance of three winter-dormant white birch species to mammalian herbivores
Authors: Laitinen Jaana , Rousi Matti , Tahvanainen Jorma , Henttonen Heikki , Heinonen Jaakko
Published: December 2004

In this study, we investigated variation in the resistance of winter-dormant white birch species (Betula resinifera Britt., Betula pendula Roth, and Betula platyphylla Sukatchev var. japonica Hara) at different ontogenetic phases to mountain hares (Lepus timidus L.) and field voles (Microtus agrestis L.). The birches were grown for 4 years in outdoor pots and in a field experiment at different nutrient levels. The species differed in their overall levels of resistance to mountain hares and in their resistance responses at different nutrient levels. The exotic species, B. resinifera and B. platyphylla, were more resistant than the native B. pendula. Variation in resistance to voles between and within species at different fertilizer levels was less pronounced. The resistance response of white birches to hares seems to be related to their ontogeny, as well as to the nutrient status of the soil. At high nutrient supply, young birch seedlings achieve good growth and high resistance, with no tradeoff between growth and resistance, but the effect of fertilization on resistance stabilizes in aging trees. Before we can arrive at any general conclusions about the resistance responses of trees in variable environmental conditions, the effect of ontogeny must be considered, as well as differences between plant genotypes.
Statistical methods for estimating historical fire frequency from multiple fire-scar data
Authors: Reed William J , Johnson Edward A
Published: December 2004

This paper considers the statistical analysis of fire-interval charts based on fire-scar data. Estimation of the fire interval (expected time between scar-registering fires at any location) by maximum likelihood is presented. Because fires spread, causing a lack of independence in scar registration at distinct sites, an overdispersed binomial model is used, leading to a two-variable quasi-likelihood function. From this, point estimates, standard errors, and approximate confidence intervals for fire interval and related quantities can be derived. Methods of testing for the significance of spatial and temporal differences are also discussed. A simple example using artificial data is given to illustrate the computational steps involved, and an analysis of real fire-scar data is presented.
Linking tree rings, summer aridity, and regional fire data: an example from the boreal forests of the Komi Republic, East European Russia
Authors: Drobyshev Igor , Niklasson Mats
Published: December 2004

To evaluate the potential use of tree-ring data as a proxy for fire activity at the scale of a large boreal region, we analyzed a set of regional tree-ring chronologies of Siberian larch (Larix sibirica L.), a spatially implicit annual fire record, and monthly climate data for the Komi Republic for the period 19501990. In most years, annually burned area was below 0.001% of the republic's forested area and reached up to 0.7% during fire-prone years. Principal components (PC) of summer aridity resolved 64.2% of the annual variation in the number of fires, 12.2% in the average fire size, and 59.2% in the annually burned area. In turn, tree-ring PCs explained 65.2% of variation in fire-related weather PCs. Dendrochronological reconstruction of the annual number of fires and of the log-transformed annually burned area predicted 27.0% and 40.1% of the high-frequency variance of these variables, respectively. Coefficient of efficiency, a measure of reconstruction usefulness, reached 0.081 (number of fires) and 0.315 (annual area burned), supporting the obtained index as a realistic proxy for regional fire activity. Decadal variation in coefficient of efficiency values suggested improved monitoring accuracy since 1960 and more effective fire suppression during the last studied decade (19801990).