bluuebunny/crossref_metadata_2025 huggingface dataset:
Repeated transsphenoidal pituitary surgery (TS) via the endoscopic technique: a good therapeutic option for recurrent or persistent Cushing's disease (CD)
Authors: Wagenmakers M. A. E. M. , Netea‐Maier R. T. , Van Lindert E. J. , Timmers H. J. L. M. , Grotenhuis J. A. , Hermus A. R. M. M.
Published: August 2008

Background No data on results of repeated transsphenoidal surgery via the endoscopic technique for patients with persistent or recurrent Cushing's disease are available.

Design and patients We retrospectively evaluated the remission rates and complications of repeated transsphenoidal surgery via the endoscopic technique in 14 patients with persistent (N = 6) or recurrent (N = 8) Cushing's disease treated in our centre between 1999 and 2007.

Main outcomes Remission was defined as the disappearance of symptoms of hypercortisolism with basal plasma cortisol level ≤ 50 nmol/l 24–48 h after glucocorticoid withdrawal and/or suppression of plasma cortisol level ≤ 50 nmol/l after 1 mg dexamethasone overnight within the first 3 months after transsphenoidal surgery.

Results With repeated endoscopic transsphenoidal surgery a remission rate of 10/14 (71%) was achieved. No patient had a relapse during a median follow‐up of 24 months. Cerebrospinal fluid leakage was the most frequent complication (6 patients) and 11 patients required hormonal substitution after surgery. The success of repeated transsphenoidal surgery could not be predicted by visualization of an adenoma on MRI before first or second surgery, histopathological confirmation of an ACTH secreting adenoma after first or second surgery, treatment with cortisol lowering agents before first or second surgery, the operation technique used during the first surgery, persistentvs.recurrent disease after the first surgery, age, gender and interval between the two surgeries.

Conclusion Repeated transsphenoidal surgery via the endoscopic technique is a good treatment option for selected patients with recurrent or persistent Cushing's disease following primary pituitary surgery.
Variant rs9939609 in the FTO gene is associated with obesity in an adult population from Spain
Authors: González‐Sánchez José L. , Zabena Carina , Martínez‐Larrad María T. , Martínez‐Calatrava María J. , Pérez‐Barba Milagros , Serrano‐Ríos Manuel
Published: August 2008

Objective  Recently independent studies, including genome‐wide scans, have shown that variation in the fat mass and obesity associated gene (FTO) were significantly associated with obesity in populations of European origin.

Design and methods  In this study we examined the association between rs9939609 FTO variant and obesity related parameters in a population based‐study of 732 unrelated individuals (46·9% males and 53·1% females; ages 35–74 years) from the province of Segovia in Central Spain (Castille).

Results  The AA genotype was significantly more frequent in obese individuals (defined as body mass index ≥ 30 kg/m2, n = 207; 80 males and 127 females) than in non‐obese (19·9%vs. 13·7%, P = 0·026). In addition to increased obesity, AA homozygous individuals had higher waist circumference than individuals with AT heterozygous and TT homozygous genotypes. The minor A‐allele of rs9939609 was associated with an increased odds ratio (OR) for obesity [OR 1·51, 95% confidence interval (CI) 1·10–2·12] as compared to the TT genotype. This difference was also statistically significant even after the adjustment for sex and age (OR 1·46, 95% CI 1·02–2·07).

Conclusions  Our results support the association of FTO gene variants with obesity, including parameters of visceral (abdominal) obesity, in an adult general population from Spain. Overall we confirm the previously reported association studies between variants in FTO gene and the risk of obesity.
Interleukin‐10–592C/A, –819C/T and –1082A/G promoter variants affect the susceptibility to nephropathy in Tunisian type 2 diabetes (T2DM) patients
Authors: Ezzidi Intissar , Mtiraoui Nabil , Kacem Maha , Mallat Samir G. , Mohamed Manel Ben Hadj , Chaieb Molka , Mahjoub Touhami , Almawi Wassim Y.
Published: August 2008

Background  The Interleukin (IL)‐10 polymorphic variants –1082G/A, –819C/T and –592C/A were linked with obesity, metabolic syndrome, and type 2 diabetes (T2DM). We investigated the hypothesis that IL‐10 promoter polymorphisms may be associated with the progression of diabetic nephropathy (DN).

Design  Case‐controlled study.

Patients  Study subjects comprised of 515 DN patients, and 402 normoalbuminuric (DWN) T2DM patients.

Measurements  IL‐10 genotyping was done by PCR‐based assays, and the contributions of the IL‐10 polymorphic variants to DN were analysed by haplotype analysis and multivariate regression analysis.

Results  Decreased prevalence of (mutant) –819T allele and –819C/T genotype was seen in DN patients; neither the –1082G/A nor the –592C/A polymorphism was associated with DN. Three‐loci haplotype (–1082GA/–819CT/–592CA) analysis identified GTC as DN‐protective haplotype. Multivariate regression analysis confirmed the association of GTC haplotype (P = 0·045; OR = 0·56, 95% CI: 0·31–0·99), and in addition identified GTA haplotype (P = 0·044; OR = 0·54, 95% CI: 0·30–0·98) as independent predictors of DN after controlling for a number of covariates (age, sex, BMI; hypertension, glucose, HbA1c, DN duration, total cholesterol, medications).

Conclusion  This study suggests that IL‐10 promoter polymorphism influence the risk of nephropathy in Tunisian T2DM patients.
The collapse of benthic macroalgal blooms in response to self‐shading
Authors: HIGGINS SCOTT N. , HECKY ROBERT E. , GUILDFORD STEPHANIE J.
Published: August 2008

1. Our goal was to use physiological indicators [photosynthesis–irradiance (P–I) response, nutrient status], population level feedbacks (self‐shading) and ambient environmental conditions (dissolved nutrients, light, temperature) to improve our understanding of the seasonal and spatial population dynamics ofCladophora.

2. Cladophoragrew in three distinct phases, rapid growth early in the season (May–July), a mid‐season population collapse (July–August) and autumn re‐growth. Across all sites and dates, mean net maximal photosynthesis [PM(NET)] was 6.9 ± 3.9 mg O2 g DM−1 h−1, and α was 0.055 ± 0.025 mg O2 g DM−1 μmphotons−1 m−2. Mean values for critical irradiance (ICR) and the half‐saturation light intensity (IK), were 42.9 ± 32.1 and 189.3 ± 123.8 μmphotons−1 m−2 s−1respectively.

3. At most sites growth was phosphorus‐limited. Values of α were significantly higher at a site influenced by a nutrient enriched river plume, where algal growth was phosphorus‐sufficient.

4. Photoinhibition was not apparent in any of our P–I experiments. Even if photoinhibition had been apparent duringin vitroP–I experiments, population level photosynthetic rates in the field would be little affected because intense self‐shading restricts inhibiting irradiances to the upper few mm–cm of the algal canopy.

5. Our physiological (P–I response) experiments contradicted previous assertions that high ambient temperatures, or nutrient deficiency, were primary causes of mid‐summer sloughing. In our study, sloughing occurred simultaneously at nutrient enriched and nutrient deficient sites, at temperatures well below critical values found duringin vitroexperiments, and our indicator of physiological condition (P–I response) remained unchanged leading up to, or immediately after, the sloughing event.

6. Self‐shading can reduce the convexity of the P–I response withinin vitroincubations, even when the amount of algal material is low. Our experiments used 0.08 g DM of algal material that formed clumpsc.1 cm thick. Under these conditions, we estimated negligible (<1%) effects on PM, a 12% reduction in apparent values of α, and 14% and 17% increases in values of the α‐dependent termsICRandIK,respectively.

7. Our results are consistent with the hypothesis that a population‐level negative feedback (self‐shading) is responsible for sloughing in dense macroalgal beds. Sloughing was probably inevitable once macroalgal bed density and thickness surpassed a critical threshold. Cells towards the base of the bed received insufficient light to maintain metabolic balance, began to decay and weaken, and became increasingly susceptible to physical detachment from shear stress.
Patterns in freshwater diatom taxonomic distinctness along an eutrophication gradient
Authors: LEIRA M. , CHEN G. , DALTON C. , IRVINE K. , TAYLOR D.
Published: August 2008

1. A variety of species richness measures have been used to assess the effects of environmental degradation on biodiversity. Such measures can be highly influenced by sample size, sampling effort, habitat type or complexity, however, and typically do not show monotonic responses to human impact. In addition to being independent of the degree of sampling effort involved in data acquisition, effective measures of biodiversity should reflect the degree of taxonomical relatedness among species within ecological assemblages and provide a basis for understanding observed diversity for a particular habitat type. Taxonomic diversity or distinctness indices emphasize the average taxonomic relatedness (i.e. degree of taxonomical closeness) between species in a community.

2. Eutrophication of freshwater ecosystems, mainly due to the increased availability of nutrients, notably phosphorus, has become a major environmental problem. Two measures of taxonomic distinctness (Average Taxonomic Distinctness and Variation in Taxonomic Distinctness) were applied to surface sediment diatoms from 45 lakes across the island of Ireland to examine whether taxonomic distinctness and nutrient enrichment were significantly related at a regional scale. The lakes span a range of concentrations of epilimnic total phosphorus (TP) and were grouped into six different types, based on depth and alkalinity levels, and three different categories according to trophic state (ultra‐oligotrophic and oligotrophic; mesotrophic; and eutrophic and hyper‐eutrophic).

3. The taxonomic distinctness measures revealed significant differences among lakes in the three different classes of trophic state, with nutrient‐rich lakes generally more taxonomically diverse than nutrient‐poor lakes. This implies that enrichment of oligotrophic lakes does not necessarily lead to a reduction in taxonomic diversity, at least as expressed by the indices used here. Furthermore, taxonomic distinctness was highly variable across the six different lake types regardless of nutrient level.

4. Results indicate that habitat availability and physical structure within the study lakes also exert a strong influence on the pattern of taxonomic diversity. Overall the results highlight problems with the use of taxonomic diversity measures for detecting impacts of freshwater eutrophication based on diatom assemblages.
Associations between cytokine/cytokine receptor single nucleotide polymorphisms and humoral immunity to measles, mumps and rubella in a Somali population
Authors: Dhiman N. , Ovsyannikova I. G. , Vierkant R. A. , Pankratz V. S. , Jacobson R. M. , Poland G. A.
Published: August 2008

We genotyped a Somali population (n = 85; age ≤30 years) for 617 cytokine and cytokine receptor single nucleotide polymorphisms (SNPs) using Illumina GoldenGate genotyping to determine associations with measles, mumps and rubella immunity. Overall, 61 significant associations (P ≤ 0.01) were found between SNPs belonging to cytokine receptor genes regulating T helper (Th)1 (IL12RB2, IL2RA and B) and Th2 (IL4R and IL10RB) immunity, and cytokine (IL1B, TNFA, IL6 and IFNB1) and cytokine receptor (IL1RA, IFNAR2, IL18R1, TNFRSF1A and B) genes regulating innate immunity and variations in antibody levels to measles, mumps and/or rubella. SNPs within two major inflammatory cytokine genes, TNFA and interleukin (IL) 6, showed associations with measles‐specific antibodies. Specifically, the minor allele variant of rs1799964 (TNFA −1211 C>T) was associated with primarily seronegative values (median enzyme immunoassay index values ≤0.87; P = 0.002; q = 0.23) in response to measles disease and/or vaccination. A heterozygous variant CT for rs2069849 (IL6 +4272C>T; Phe201Phe) was also associated with seronegative values and a lower median level of antibody response to measles disease and/or vaccination (P = 0.004; q = 0.36) or measles vaccination alone (P = 0.008). Several SNPs within the coding and regulatory regions of cytokine and cytokine receptor genes showed associations with mumps and rubella antibody levels but were less informative as strong linkage disequilibrium patterns and lower frequencies for minor alleles were observed among these SNPs. Our study identifies specific SNPs in innate immune response genes that may play a role in modulating antibody responses to measles vaccination and/or infection in Somali subjects.
Ozone‐induced changes in photosynthesis and photorespiration of hybrid poplar in relation to the developmental stage of the leaves
Authors: Bagard Matthieu , Le Thiec Didier , Delacote Emilien , Hasenfratz‐Sauder Marie‐Paule , Banvoy Jacques , Gérard Joëlle , Dizengremel Pierre , Jolivet Yves
Published: August 2008

Young poplar trees (Populus tremula Michx. × Populus alba L. clone INRA 717‐1B4) were subjected to 120 ppb of ozone for 35 days in phytotronic chambers. Treated trees displayed precocious leaf senescence and visible symptoms of injury (dark brown/black upper surface stippling) exclusively observed on fully expanded leaves. In these leaves, ozone reduced parameters related to photochemistry (Chl content and maximum rate of photosynthetic electron transport) and photosynthetic CO2 fixation [net CO2 assimilation, Rubisco (ribulose‐1,5‐bisphosphate carboxylase oxygenase) activity and maximum velocity of Rubisco for carboxylation]. In fully expanded leaves, the rate of photorespiration as estimated from Chl fluorescence was markedly impaired by the ozone treatment together with the activity of photorespiratory enzymes (Rubisco and glycolate oxidase). Immunoblot analysis revealed a decrease in the content of serine hydroxymethyltransferase in treated mature leaves, while the content of the H subunit of the glycine decarboxylase complex was not modified. Leaves in the early period of expansion were exempt from visible symptoms of injury and remained unaffected as regards all measured parameters. Leaves reaching full expansion under ozone exposure showed potential responses of protection (stimulation of mitochondrial respiration and transitory stomatal closure). Our data underline the major role of leaf phenology in ozone sensitivity of photosynthetic processes and reveal a marked ozone‐induced inhibition of photorespiration.
Suppression of SERK gene expression affects fungus tolerance and somatic embryogenesis in transgenic lettuce
Authors: Santos M. O. , Romano E. , Vieira L. S. , Baldoni A. B. , Aragão F. J. L.
Published: August 2008

The Somatic embryogenesis receptor‐like kinase (SERK) gene plays an important role in plant somatic and zygotic embryogenesis induction. The gene encodes an LRR‐containing receptor‐like kinase protein. Studies have been carried out focusing on different aspects of its function, but definitive conclusions on its role are far from being reached. SERK expression is generally detected in cells in which somatic or zygotic embryogenesis has been triggered. Transgenic lettuce lines were produced to silence the endogenous SERK gene using antisense RNA. The average number of seeds per flower in the R1 and R2 generations was similar for both transgenic and non‐transgenic lines. However, a reduction in the number of viable grained seeds was observed in four studied transgenic lines. Endogenous SERK expression analysis revealed the absence of detectable LsSERK gene transcripts in three transgenic lines, which presented a reduction in their ability to form in vitro somatic embryonic structures. In addition, transgenic lines showed enhanced susceptibility to the pathogenic fungus Sclerotinia sclerotiorum, when compared to control plants. The results support the idea that SERK genes might not only be involved in plant growth and development, but probably also in a general mechanism of biotic and abiotic stress perception.
Sex‐specific physiological, allocation and growth responses to water availability in the subdioecious plant Honckenya peploides
Authors: Sánchez‐Vilas J. , Retuerto R.
Published: August 2008

The gender of dimorphic plant species is often affected by ecophysiological variables. Differences have been interpreted as a response of the sexes to meet specific resource demands associated with reproduction. This study investigated whether sex‐specific variations in ecophysiological traits in response to water availability determine the performance of each sex in different habitats, and therefore promote extreme spatial segregation of the sexes in the subdioecious plant, Honckenya peploides. Twenty‐seven plants of each sex were individually potted in dune sand and assigned randomly to one of three water treatments. Well‐watered plants were watered daily to field capacity, whereas plants in the moderate and high‐water stress treatments received 40% and 20%, respectively, of the water given to well‐watered plants. Photochemical efficiency, leaf spectral properties and components of relative growth rate (leaf area ratio and net assimilation rate) were measured. Photochemical efficiencies integrated over time were higher in male than in female plants. Water deficit decreased maximum quantum yield in female plants more rapidly than in male plants, but female plants (unlike male plants) had recovered to initial values by the end of the experiment. Maximum quantum yield in male plants was more affected by water stress than in female plants, indicating that male plants were more susceptible to photoinhibition. The two sexes did not differ in growth rate, but male plants invested a higher proportion of their biomass in leaves, had a higher leaf area per unit biomass and lower net assimilation rate relative to female plants. Female plants had a higher water content and succulence than male plants. Differences in stomatal density between the sexes depended on water availability. The results suggest that the two sexes of H. peploides have different strategies for coping with water stress. The study also provides evidence of sex differences in allocation traits. We conclude that between‐sex differences in ecophysiological and allocation traits may contribute to explain habitat‐related between‐sex differences in performance and, therefore, the spatial segregation of the sexes.
Isolation of Resistance Gene Analogues from Flowering Dogwood (Cornus florida L.)
Authors: Shi Ainong , Kantartzi Stella K. , Mmbaga Margaret , Chen Pengyin
Published: August 2008

Cloned resistance (R) genes from a broad range of plant species are known to share similarities in DNA sequences and structural motifs. Oligonucleotide primers, designed to conserved regions of nucleotide binding site (NBS) motifs within previously cloned pathogen resistance genes, were used to amplify resistance gene analogues (RGAs) from dogwood. Twenty eight unique dogwood RGA sequences were identified and subdivided into 11 groups on the basis of nucleic acid sequence‐identity of approximately 70% or greater. Phylogenetic analysis of the predicted amino acid sequences grouped the RGAs into three distinct classes from which several subgroups were delineated based on nucleic acid sequences. Gene database searches with the consensus protein sequences of each of the three classes and respective subgroups of dogwood RGAs revealed their conserved NBS domains and homology to RGAs and known resistance genes from a variety of plant genera. Given the complete lack of knowledge regarding molecular organization of R genes in dogwood, the cloned RGAs described here may be useful as probes to map, characterize, and manipulate R genes of the dogwood genome.
Exfoliative cytology as a rapid diagnostic tool for lobomycosis
Authors: Talhari Carolina , Chrusciak‐Talhari Anette , De Souza João Vicente Braga , Araújo José Ribamar , Talhari Sinésio
Published: August 2008

Lobomycosis is a common subcutaneous mycosis in South America. It is caused by Lacazia loboi. We report two cases of lobomycosis which were diagnosed by exfoliative cytology without any special staining. We highlight this diagnostic tool as a simple, low‐cost, painless, non‐invasive and fast method for the diagnosis of lobomycosis.
Trichosporon asahii as a prospective pathogen in solid organ transplant recipients
Authors: Netsvyetayeva I. , Swoboda‐Kopeć E. , Paczek L. , Fiedor P. , Sikora M. , Jaworska‐Zaremba M. , Blachnio S. , Luczak M.
Published: August 2008

Trichosporon spp. is not an important factor of mycotic infections in immunocompetent patients. It may be a cause of invasive mycoses with a high mortality rate in patients undergoing solid organ transplantation. We have analysed the antifungal agents' susceptibility of Trichosporon asahii and its frequency of occurrence as a prospective etiological agent of infections in liver, kidney and simultaneous pancreas–kidney transplant recipients. Clinical specimens (urine, blood, peritoneal fluid and swabs) were obtained from patients hospitalised in the Institute of Transplantation Medicine, Department of General and Transplantation Surgery, Medical University of Warsaw in 2005 and 2006. Microbiological tests were performed in Mycological Laboratory, Department of Microbiology, Medical University of Warsaw. A total of 475 strains of yeast‐like fungi were isolated from clinical specimens taken from 263 liver, kidney and simultaneous pancreas–kidney transplant recipients and from 26 organ donors. Trichosporon asahii was found in 26 clinical samples taken from 18 patients and one organ donor. Positive cultures were obtained from 22 urine samples, one stoma fluid, one wound swab, one tracheal aspirate and one ejaculate. Isolates of Trichosporon asahii were found in 6% of total positive mycological cultures in the solid organ transplant recipients. Among cultured strains, 11 isolates were resistant to fluconazole, four to itraconazole and three of them demonstrated resistance to amphotericin B.
Identification and analysis of four candidate symbiosis genes from ‘Chlorochromatium aggregatum’, a highly developed bacterial symbiosis
Authors: Vogl Kajetan , Wenter Roland , Dreßen Martina , Schlickenrieder Martina , Plöscher Matthias , Eichacker Lutz , Overmann Jörg
Published: August 2008

The consortium ‘Chlorochromatium aggregatum’ currently represents the most highly developed interspecific association between prokaryotes. It consists of green sulfur bacteria, so‐called epibionts, which surround a central, motile, chemotrophic bacterium. Four putative symbiosis genes of the epibiont were recovered by suppression subtractive hybridization and bioinformatics approaches. These genes are transcribed constitutively and do not occur in the free‐living relatives of the epibiont. The haemagglutinin‐like putative gene products of open reading frames (ORFs) Cag0614 and Cag0616 are unusually large and contain repetitive regions and RGD tripeptides. Cag0616 harbours two βγ‐crystalline Greek key motifs. Cag1920 codes for a putative haemolysin whereas the gene product of Cag1919 is a putative RTX‐like protein. Based on detailed analyses of Cag1919, the C‐terminal amino acid sequence comprises six repetitions of the motif GGXGXD predicted to form a Ca2+‐binding beta roll. Intact ‘C. aggregatum’ consortia disaggregated upon the addition of EGTA or pyrophosphate, but stayed intact in the presence of various lectine‐binding sugars or proteolytic enzymes. Unlike other RTX toxins, a gene product of Cag1919 could not be detected by 45Ca2+ autoradiography, indicating a low abundance of the corresponding protein in the cells. The RTX‐type C‐terminus coded by Cag1919 exhibited a significant similarity to RTX modules of various proteobacterial proteins, suggesting that this putative symbiosis gene has been acquired via horizontal gene transfer from a proteobacterium.
Endosymbioses between bacteria and deep‐sea siboglinid tubeworms from an Arctic Cold Seep (Haakon Mosby Mud Volcano, Barents Sea)
Authors: Lösekann Tina , Robador Alberto , Niemann Helge , Knittel Katrin , Boetius Antje , Dubilier Nicole
Published: August 2008

Siboglinid tubeworms do not have a mouth or gut and live in obligate associations with bacterial endosymbionts. Little is currently known about the phylogeny of frenulate and moniliferan siboglinids and their symbionts. In this study, we investigated the symbioses of two co‐occurring siboglinid species from a methane emitting mud volcano in the Arctic Ocean (Haakon Mosby Mud Volcano, HMMV): Oligobrachia haakonmosbiensis (Frenulata) and Sclerolinum contortum (Monilifera). Comparative sequence analysis of the host‐specific 18S and the symbiont‐specific 16S rRNA genes of S. contortum showed that the close phylogenetic relationship of this host to vestimentiferan siboglinids was mirrored in the close relationship of its symbionts to the sulfur‐oxidizing gammaproteobacterial symbionts of vestimentiferans. A similar congruence between host and symbiont phylogeny was observed in O. haakonmosbiensis: both this host and its symbionts were most closely related to the frenulate siboglinid O. mashikoi and its gammaproteobacterial symbiont. The symbiont sequences from O. haakonmosbiensis and O. mashikoi formed a clade unaffiliated with known methane‐ or sulfur‐oxidizing bacteria. Fluorescence in situ hybridization indicated that the dominant bacterial phylotypes originated from endosymbionts residing inside the host trophosome. In both S. contortum and O. haakonmosbiensis, characteristic genes for autotrophy (cbbLM) and sulfur oxidation (aprA) were present, while genes diagnostic for methanotrophy were not detected. The molecular data suggest that both HMMV tubeworm species harbour chemoautotrophic sulfur‐oxidizing symbionts. In S. contortum, average stable carbon isotope values of fatty acids and cholesterol of −43‰ were highly negative for a sulfur oxidizing symbiosis, but can be explained by a 13C‐depleted CO2 source at HMMV. In O. haakonmosbiensis, stable carbon isotope values of fatty acids and cholesterol of −70‰ are difficult to reconcile with our current knowledge of isotope signatures for chemoautotrophic processes.
Use of benzoate as an electron acceptor by Syntrophus aciditrophicus grown in pure culture with crotonate
Authors: Mouttaki Housna , Nanny Mark A. , McInerney Michael J.
Published: August 2008

In methanogenic environments, the main fate of benzoate is its oxidization to acetate, H2 and CO2 by syntrophic associations of hydrogen‐producing benzoate degraders and hydrogen‐using methanogens. Here, we report the use of benzoate as an electron acceptor. Pure cultures of S. aciditrophicus simultaneously degraded crotonate and benzoate when both substrates were present. The growth rate was 0.007 h−1 with crotonate and benzoate present compared with 0.025 h−1 with crotonate alone. After 8 days of incubation, 4.12 ± 0.50 mM of cyclohexane carboxylate and 8.40 ± 0.61 mM of acetate were formed and 4.0 ± 0.04 mM of benzoate and 4.8 ± 0.5 mM of crotonate were consumed. The molar growth yield was 22.7 ± 2.1 g (dry wt) of cells per mol of crotonate compared with about 14.0 ± 0.1 g (dry wt) of cells per mol of crotonate when S. aciditrophicus was grown with crotonate alone. Cultures grown with [ring‐13C]‐benzoate and unlabelled crotonate initially formed [ring‐13C]‐labelled cyclohexane carboxylate. No 13C‐labelled acetate was detected. In addition to cyclohexane carboxylate, 13C‐labelled cyclohex‐1‐ene carboxylate was detected as an intermediate. Once almost all of the benzoate was gone, carbon isotopic analyses showed that cyclohexane carboxylate was formed from both labelled and non‐labelled metabolites. Glutarate and pimelate were also detected at this time and carbon isotopic analyses showed that each was made from a mixture labelled and non‐labelled metabolites. The increase in molar growth yield with crotonate and benzoate and the formation of [ring‐13C]‐cyclohexane carboxylate from [ring‐13C]‐benzoate in the presence of crotonate are consistent with benzoate serving as an electron acceptor.
Global distribution and diversity of coral‐associated Archaea and their possible role in the coral holobiont nitrogen cycle
Authors: Siboni Nachshon , Ben‐Dov Eitan , Sivan Alex , Kushmaro Ariel
Published: August 2008

Diversity, distribution and genetic comparison of Archaea associated with the surface mucus of corals from three genera, namely Acanthastrea sp., Favia sp. and Fungia sp., from the Gulf of Eilat, Israel and from Heron Island, Australia were studied. Sequencing of the 16S rRNA gene of the coral‐associated Archaea revealed dominance of Crenarchaeota (79%, on average). In this phylum, 87% of the sequences were similar (≥ 97%) to the Thermoprotei, with 76% of these being similar (≥ 97%) to the ammonium oxidizer, Nitrosopumilus maritimus. Most of the coral‐associated euryarchaeotal sequences (69%) were related to marine group II, while other euryarchaeotal clades were found to be related to anaerobic methanotrophs (8%), anaerobic nitrate reducers (i.e. denitrification, 15%) and marine group III (8%). Most of the crenarchaeotal and euryarchaeotal coral‐associated 16S rRNA gene sequences from Heron Island (61%) and from the Gulf of Eilat (71%) were closely related (≥ 97%) to sequences previously derived from corals from the Virgin Islands. Analysis of archaeal amoA sequences obtained from the fungiid coral, Fungia granulosa, divided into three clades, all related to archaeal sequences previously obtained from the marine environment. These sequences were distantly related to amoA sequences previously found in association with other coral species. Preliminary experiments suggest that there is active oxidation of ammonia to nitrite in the mucus of F. granulosa. Thus, coral‐associated Archaea may contribute to nitrogen recycling in the holobiont, presumably by acting as a nutritional sink for excess ammonium trapped in the mucus layer, through nitrification and denitrification processes.
“I've also experienced loss and fear”: Effects of prior similar experience on empathy
Authors: EKLUND JAKOB , ANDERSSON‐STRÅBERG TERESIA , HANSEN ERIC M.
Published: August 2008

Although it is frequently argued that empathy is increased by similar experiences, this idea has rarely been tested. This study investigated the relationship between empathy and prior similar experience. Participants read four different stories and rated the degree of empathy they felt. They also reported the extent to which they had prior similar experience of the events in the stories. We found that these self‐reports of prior similar experience increased empathy for the persons in the stories. Similar experience may be an important situational antecedent for feeling empathy for another person. Pointing out similarities among experiences may be a fruitful means of training empathy.
Neural correlates of variable working memory load across adult age and skill: Dissociative patterns within the fronto‐parietal network
Authors: NYBERG LARS , DAHLIN ERIKA , STIGSDOTTER NEELY ANNA , BÄCKMAN LARS
Published: August 2008

We examined neural changes related to variations in working memory load by using an n‐back task with three levels and functional magnetic resonance imaging. Younger adults were divided into high‐ and low‐performing groups (Young‐High; Young‐Low) and compared with older adults. Relative to Young‐High, capacity‐constraints in working memory were apparent between load 1–2 for the elderly and between load 2–3 for Young‐Low. Capacity‐constraints in neural activity followed this pattern by showing a monotonically increasing response in parietal cortex and thalamus for Young‐High, whereas activity leveled off at 1‐back for the elderly and at 2‐back for Young‐Low. The response in dorsal frontal cortex followed a similar pattern with the addition that the magnitude of activation differed within capacity limitations (Old > Young at 1‐back; Young‐Low > Young‐High at 2‐back). These findings indicate that an important determinant of WM capacity is the ability to keep the frontal cortex adequately engaged in relation to current task demands.
TYPES OF AGRARIAN REFORM AND THEIR CONTRADICTIONS: THE CASE OF CHILE*
Authors: Kay Cristobal
Published: August 2008

The purpose of this article is to analyze the limitations and contradictions of agrarian reforms. Basically two types of agrarian reforms are distinguished: reformist and radical. Both types are analysed by drawing on the Chilean experience. The aims and the implementation of each type of agrarian reform are presented before proceeding to their assessment. The contradictions which emerge between the economic, social and political consequences of the two types of agrarian reform are highlighted. Finally the analysis of the peasants' estates seizures in the Melipilla region during the Allende government shows the high degree of organization and class consciousness achieved by the peasantry, but above all it reveals the limitations and contradictions of the “Chilean road to Socialism”.

Le but de cet article est d'analyser les limites et les contradictions des réformes agraires. Fondamentalement, deux types de réformes agraires sont distingués: le type réformiste et le type radical. Ces deux types sont analysés sur la base de l'expérience chilienne. L'appréciation de chaque type de réforme agraire est précédée par une présentation de ses buts et de sa mise en oeuvre. Les contradictions entre les conséquences économiques, sociales et politiques des deux types de réformes sont mises en évidence. Finalement l'analyse des occupations de propriétés foncières par les paysans dans le région de Melipilla sous le gouvernement Allende révèle le haut degré d'organisation et de conscience de classe atteint par la classe paysanne. Mais elle révèle surtout les limites de la ≪voie chilienne vers le socialisme≫.

Absicht dieses Artikels ist es, die Grenzen und Widersprüche von Agrarreformen zu analysieren. Grundsätzlich können zwei Typen unterschieden werden: der reformistische und der radikale. Beide Typen werden am Beispiel der chilenischen Erfahrung untersucht. Die Ziele und die Durchführung jedes Typs werden vor der eigentlichen Analyse erläutert.

Die Widersprüche, welche zwischen den wirtschaftlichen, sozialen und politischen Konsequenzen der zwei Typen von Agrarreformen sichtbar werden, werden stark hervorgehoben. Abschließend zeigt die Analyse der Beschlagnahmung des bäuerlichen Grundbesitzes in der Melipilla‐Region während der Zeit der Allende‐Regierung den hohen Grad der Organisation und des Klassenbewußtseins unter den Bauern, aber vor allem auch offenbart sie die Grenzen und Widersprüche des “Chilenischen Weges des Sozialismus”.
Fitting Stochastic Volatility Models in the Presence of Irregular Sampling via Particle Methods and the EM Algorithm
Authors: Kim Jeongeun , Stoffer David S.
Published: August 2008

Abstract. Stochastic volatility (SV) models have become increasingly popular for explaining the behaviour of financial variables such as stock prices and exchange rates, and their popularity has resulted in several different proposed approaches to estimating the parameters of the model. An important feature of financial data, which is commonly ignored, is the occurrence of irregular sampling because of holidays or unexpected events. We present a method that can handle the estimation problem of SV models when the sampling is somewhat irregular. The basic idea of our approach is to combine the expectation‐maximization (EM) algorithm with particle filters and smoothers in order to estimate parameters of the model. In addition, we expand the scope of application of SV models by adopting a normal mixture, with unknown parameters, for the observational error term rather than assuming a log‐chi‐squared distribution. We address the problems by using state–space models and imputation. Finally, we present simulation studies and real data analyses to establish the viability of the proposed method.
Break Detection for a Class of Nonlinear Time Series Models
Authors: Davis Richard A. , Lee Thomas C. M. , Rodriguez‐Yam Gabriel A.
Published: August 2008

Abstract.  This article considers the problem of detecting break points for a nonstationary time series. Specifically, the time series is assumed to follow a parametric nonlinear time‐series model in which the parameters may change values at fixed times. In this formulation, the number and locations of the break points are assumed unknown. The minimum description length (MDL) is used as a criterion for estimating the number of break points, the locations of break points and the parametric model in each segment. The best segmentation found by minimizing MDL is obtained using a genetic algorithm. The implementation of this approach is illustrated using generalized autoregressive conditionally heteroscedastic (GARCH) models, stochastic volatility models and generalized state‐space models as the parametric model for the segments. Empirical results show good performance of the estimates of the number of breaks and their locations for these various models.
Uniform limit theorems for the integrated periodogram of weakly dependent time series and their applications to Whittle's estimate
Authors: Bardet Jean‐Marc , Doukhan Paul , León José Rafael
Published: August 2008

Abstract.  We prove uniform convergence results for the integrated periodogram of a weakly dependent time series, namely a strong law of large numbers and a central limit theorem. These results are applied to Whittle's parametric estimation. Under general weak‐dependence assumptions, the strong consistency and asymptotic normality of Whittle's estimate are established for a large class of models. For instance, the causal θ‐weak dependence property allows a new and unified proof of those results for autoregressive conditionally heteroscedastic (ARCH)(∞) and bilinear processes. Non‐causal η‐weak dependence yields the same limit theorems for two‐sided linear (with dependent inputs) or Volterra processes.
Automating construction of a domain ontology using a projective adaptive resonance theory neural network and Bayesian network
Authors: Chen Rung‐Ching , Chuang Cheng‐Han
Published: August 2008

Abstract: Research on semantic webs has become increasingly widespread in the computer science community. The core technology of a semantic web is an artefact called an ontology. The major problem in constructing an ontology is the long period of time required. Another problem is the large number of possible meanings for the knowledge in the ontology. In this paper, we present a novel ontology construction based on artificial neural networks and a Bayesian network. First, we collected web pages related to the problem domain using search engines. The system then used the labels of the HTML tags to select keywords, and used WordNet to determine the meaningful keywords, called terms. Next, it calculated the entropy value to determine the weight of the terms. After the above steps, the projective adaptive resonance theory neural network clustered the collected web pages and found the representative term of each cluster of web pages using the entropy value. The system then used a Bayesian network to insert the terms and complete the hierarchy of the ontology. Finally, the system used a resource description framework to store and express the ontology results.
Contact dermatitis in car repair workers
Authors: Attwa E , El‐Laithy N
Published: August 2008

Background  Occupational contact dermatitis (OCD) is a common skin disorder with a poor prognosis.

Objectives  The objectives of this study were to (1) estimate the prevalence of CD among car repair workers, (2) study some risk factors associated with CD, and (3) conduct an intervention skin care education program.

Subjects and methods  A cross‐sectional study was conducted in 87 car repair workers with regular and direct exposure to chemicals at the industrial zone in Zagazig City, Egypt and 76 unexposed assembly booksellers. All workers were subjected to a questionnaire and clinical examination, and those who were diagnosed clinically as CD were patch tested. Intervention study with a skin care education program was carried out on 47 car repair workers. Re‐evaluation of the intervention group after 5 months was done.

Results  The total prevalence of CD among car repair workers (18.4%) was significantly higher compared with their controls (3.9%), with the highest prevalence among car mechanics (24.1%) and painters (20.7%); 16.1% of them reported recurrent dermatitis in the last 12 months. Nickel accounted for most positive patch test reactions (33.3%). A significant association was noticed between the prevalence of CD and age, smoking, atopic background and duration of work. After the intervention study, a significantly higher knowledge level about CD was reported.

Conclusion  The most important risk factors for OCD among the car repair workers are atopic background and long duration of work. Skin care education program is an important tool for prevention of CD and control of exposure to substances hazardous to the skin.

Conflicts of interest

None declared
Breaking bad news of cancer to people with learning disabilities
Authors: McEnhill Linda S
Published: August 2008

Accessible summary

When some one gets cancer the doctor, most times, tells them about it and does not keep it a secret.

Because this can be very upsetting, the government pays for special training to help doctors and nurses to do this well.

The training does not include anything about the needs of people with learning disabilities.

Some people with learning disabilities were asked whether the doctor had told them when they were ill, and most of them said ‘no’.

Learning disability staff need to help doctors and nurses understand how to speak to people with learning disabilities. People with learning disabilities need to understand about their illness and be involved in decisions about their treatment.

Since the 1970s, medical staff have routinely disclosed the diagnosis of cancer to their patients. However, this has often been carried out unskilfully causing distress to the patient and impairing their ability to comply with treatment. In response, the government has invested in ‘Advanced Communication Skills training’ for oncology staff. Despite the subsequent advances made in communicating with the general public, this article will show that a small‐scale audit of people with learning disabilities demonstrated that often doctors do not communicate directly with people with learning disabilities about serious illness. It will also suggest that, the current ‘breaking bad news’ models do not meet the communication needs of people with learning disabilities. This article explores the findings of the audit and its implications for practice and ends by sign posting to useful resources for communicating the bad news of a life‐threatening illness to people with learning disabilities.
Doing research on people with learning disabilities, cancer and dying: ethics, possibilities and pitfalls
Authors: Tuffrey‐Wijne Irene , Bernal Jane , Hollins Sheila
Published: August 2008

Accessible summary

We have done research about cancer, death and dying. People with learning disabilities who had cancer were in our studies. This paper is about making sure that our research is ethical. This means that we don’t want to cause any harm (or make people upset) when we do the research. We ask:

How do we find people to be in our studies?

What should we do if people cannot understand the research they are in?

What should we do if people do not want us to use a made‐up name in our writing?

What should we do if, during the research, we see that people with learning disabilities are not treated right?

What is the relationship with the researcher? Is the researcher a nurse, a helper or a friend?

There has been increasing recognition of the fact that people with learning disabilities can and should be involved as active participants in research. However, in the area of cancer and palliative care, they continue to be protected and excluded from contributing to expanding our knowledge base and the shaping of care provision. This paper explores the issues involved in including people with learning disabilities as participants in research around cancer, death and dying. It stems from the authors’ own experience of conducting research around cancer and palliative care, where people with learning disabilities were the key informants. Methodological issues include the choice of methodology and problems around recruiting a sample. Ethical issues include informed consent, participants’ requests to forego anonymity, observation of sub‐optimal care and issues around the boundaries between the roles of researcher and clinician.
Frank Clark
Authors: Holman Andrew
Published: August 2008

Professor Frank Clark has always worked with people with learning disabilities in some way.

He helped a lot of people move out of hospitals and live a better life.

He has also made sure that many people with learning disabilities get equal health care.

Frank has worked in a hospice where people also got equal care and services when they were dying or had someone they knew die.
MINERO‐PETROGRAPHIC AND GEOCHEMICAL CHARACTERIZATION OF ‘GRECO SCRITTO’ MARBLE FROM CAP DE GARDE, NEAR HIPPO REGIUS (ANNABA, ALGERIA)*
Authors: ANTONELLI F. , LAZZARINI L. , CANCELLIERE S. , DESSANDIER D.
Published: August 2008

This work presents the results of the first mineralogical, petrographical and geochemical characterization of the marble quarried from the Cap de Garde headland, not far from Annaba (Algeria). This site is traditionally held by archaeologists to be the main source of supply of the so‐called ‘greco scritto’ marble, which was much used by the Romans for architectural and decorative–ornamental purposes, locally from the first century bc, and in Rome and central and southern Italy from the late Flavian period until the fourth century ad. The databank relating to the quarried material, created here for the first time, is used to establish the origin of ‘greco scritto’ found in six important Roman cities of North Africa: Hippo Regius and Cuicul (Djemila), in Algeria; Volubilis, in Morocco; Cyrene, in Libya; and Carthage and Utica in Tunisia. The results of this archaeometric study support the hypothesis (already put forward by authors) that the ‘greco scritto’used in the Roman Mediterranean originated from different sites, and suggest the existence of a number of North African quarries, also in the vicinity of Annaba.
Primetime Spin: Media Bias and Belief Confirming Information
Authors: Burke Jeremy
Published: August 2008

This paper develops a model of media bias in which rational agents acquire all their news from the source that is most likely to confirm their prior beliefs. Despite only wishing to make the correct decision, agents act as if they enjoy receiving news that supports their preconceptions. By exclusively gathering information from a source biased towards his prior, there is little chance an agent will be persuaded to change his mind. Moreover, it is shown that even an unbiased agent prefers to receive biased news as it is unlikely to produce conflicting reports. The media caters to the informational demands of consumers and accordingly slants its reporting. It is shown that competition may not decrease bias, but may actually enhance it. Finally, even when it increases bias, competition may improve welfare by expanding the market for news.
THE PERFORMANCE OF THE 1980S CALIFORNIA INSURANCE AND LIABILITY REFORMS
Authors: Viscusi W. Kip , Born Patricia
Published: August 2008

Abstract: The authors examine the impact of Proposition 103. They contend that Proposition 103 reforms did not come at the expense of insurer profitability. Rather than exhibiting a decline in profitability following the adoption of Proposition 103, there was a substantial improvement in profitability which remains quite high relative to the rest of the country.
EXPENSE RATIOS ACROSS INSURANCE DISTRIBUTION SYSTEMS: AN ANALYSIS BY LINE OF BUSINESS
Authors: Regan Laureen
Published: August 2008

Abstract: The author examines whether independent agency insurers are more expensive to operate than direct writers in personal auto insurance, workers compensation, or general liability.