bluuebunny/crossref_metadata_2025 huggingface dataset:
Lateral and anterior thalamic lesions impair independent memory systems
Authors: Mitchell Anna S. , Dalrymple-Alford John C.
Published: June 2006

Damage to the medial region of the thalamus, both in clinical cases (e.g., patients with infarcts or the Korsakoff’s syndrome) and animal lesion models, is associated with variable amnesic deficits. Some studies suggest that many of these memory deficits rely on the presence of lateral thalamic lesions (LT) that include the intralaminar nuclei, presumably by altering normal function between the striatum and frontal cortex. Other studies suggest that the anterior thalamic nuclei (AT) may be more critical, as a result of disruption to an extended hippocampal system. Here, highly selective LT and AT lesions were made to test the prediction that these two regions contribute to two different memory systems. Only LT lesions produced deficits on a preoperatively acquired response-related (egocentric) working memory task, tested in a cross-maze. Conversely, only AT lesions impaired postoperative acquisition of spatial working memory, tested in a radial maze. These findings provide the first direct evidence of a double dissociation between the LT and AT neural aggregates. As the lateral and the anterior medial thalamus influence parallel independent memory processing systems, they may each contribute to memory deficits, depending on lesion extent in clinical and experimental cases of thalamic amnesia.
ERK/MAPK regulates hippocampal histone phosphorylation following contextual fear conditioning
Authors: Chwang Wilson B. , O’Riordan Kenneth J. , Levenson Jonathan M. , Sweatt J. David
Published: June 2006

Long-term memory formation is regulated by many distinct molecular mechanisms that control gene expression. An emerging model for effecting a stable, coordinated pattern of gene transcription involves epigenetic tagging through modifications of histones or DNA. In this study, we investigated the regulation of histone phosphorylation in the hippocampus by the ERK/MAPK (extracellular signal-regulated kinase/mitogen-activated protein kinase) pathway. We found that activation of ERK/MAPK in vitro significantly increased histone H3 phosphorylation in hippocampal area CA1. Furthermore, we found that contextual fear conditioning in vivo leads to a rapid time-dependent increase in histone H3 phosphorylation in area CA1. This increase paralleled the time course of contextual fear-dependent activation of ERK, and was inhibited in vivo by a latent inhibition paradigm as well as by injection of an N-methyl-d-aspartic acid receptor (NMDA-R) antagonist. Finally, injection of an inhibitor of MEK (MAP kinase/ERK kinase), the unique dual-specificity kinase upstream of ERK, blocked the increase in histone H3 phosphorylation seen after contextual fear conditioning. These results demonstrate that changes in histone phosphorylation in the hippocampus are regulated by ERK/MAPK following a behavioral fear conditioning paradigm.
Purkinje cell loss by OX7-saporin impairs acquisition and extinction of eyeblink conditioning
Authors: Nolan Brian C. , Freeman John H.
Published: June 2006

The current study examined the effects of globally depleting Purkinje cells in the cerebellar cortex with the immunotoxin OX7-saporin on acquisition and extinction of delay eyeblink conditioning in rats. Rats were given OX7-saporin or saline 2 wk before the start of eyeblink conditioning. The rats that reached a performance criterion of two consecutive days with 80% or greater conditioned responses were given 5 d of extinction training followed by 2 d of reacquisition training. Rats that received infusions of OX7-saporin had 77.2%–97.9% Purkinje cell loss and exhibited impaired acquisition and extinction. The amount of Purkinje cell loss was correlated with the magnitude of the acquisition and extinction impairments. The highest correlations between Purkinje cell number and the rate of acquisition were in lobule HVI and the anterior lobe. The highest negative correlation between Purkinje cell number and the percentage of conditioned responses during extinction was in the anterior lobe. The results indicate that cerebellar Purkinje cells, particularly in the anterior lobe and lobule HVI, play significant roles in acquisition and extinction of eyeblink conditioning.
555. Ixia Tenuifolia
Authors: Duncan Graham
Published: June 2006

Summary. The history, taxonomy, distribution and cultivation requirements of the South AfricanIxia tenuifoliaVahl (Iridaceae) are discussed; a full botanical description and illustration are provided.
556. Polystachya Longiscapa
Authors: Cribb Phillip , King Kathleen
Published: June 2006

Summary.  Polystachya longiscapa Summerh. (Orchidaceae) is illustrated. A full description of the species is provided and its relationships are discussed. A detailed account of its cultivation at Kew is given.
557. Eucrosia Mirabilis
Authors: Mathew Brian , Lewis Gwilym
Published: June 2006

Summary.  Eucrosia mirabilis(Baker) Pax (Amaryllidaceae) is illustrated. A full description of the species is provided, its taxonomy and relationships are discussed and recommendations are made for its successful cultivation.
559. Sonchus Acaulis
Authors: Hind Nicholas
Published: June 2006

Summary.  Sonchus acaulis is described and illustrated. Its position within Sonchus subgenus Dendrosonchus is discussed along with its cultivation and historical uses in the Canary Islands.
Effect of naproxen on gastric acid secretion and gastric pH
Authors: RODRIGUEZ‐STANLEY S. , REDINGER N. , MINER P. B.
Published: June 2006

Background

The mechanisms for the non‐steroidal anti‐inflammatory drug‐induced inflammation in the stomach are unclear.

Aims

To determine if naproxen (Naprosyn, Roche, Nutley, NJ, USA) alters basal acid output, pentagastrin‐stimulated maximal acid output, or fasting gastrin.

Methods

Basal acid output and maximal acid output gastric aspirations were performed pre‐naproxen and 7 days post‐naproxen 500 mg b.d. in 24 healthy subjects. Volume, pH and acid mEq were determined. Fasting gastrin was obtained. Comparisons were made using paired t‐tests (α = 0.05).

Results

Dosing with naproxen did not statistically decrease mean pH of the basal acid output gastric fluid (3.3 vs. 3.1; N.S.) or the pentagastrin‐stimulated maximal acid output gastric fluid (2.7 vs. 2.6; N.S.). Basal acid output total volume was significantly decreased post‐naproxen (84 vs. 61 mL/h; P = 0.01), with no change in maximal acid output total volume (196 vs. 188 mL/h; N.S.). Basal acid output mean gastric acidity was significantly increased post‐naproxen (0.04 vs. 0.05 mEq/mL; P = 0.03), with no change in maximal acid output mean gastric acidity after naproxen (0.10 vs. 0.10; N.S.). Gastrin was not altered by dosing with naproxen.

Conclusions

Naproxen does not influence total acid secreted but does decrease basal gastric fluid volume, thereby increasing basal gastric acid concentration. These observations define one mechanism by which non‐steroidal anti‐inflammatory drugs may induce gastric injury.
Comparison of a monoclonal with a polyclonal antibody‐based enzyme immunoassay stool test in diagnosing Helicobacter pylori infection before and after eradication therapy
Authors: DOMÍNGUEZ J. , FORNÉ M. , BLANCO S. , PRAT C. , GALÍ N. , LATORRE I. , VIVER J. M. , AUSINA V.
Published: June 2006

Background

Detection of Helicobacter pylori antigen in stool samples has been a subject of controversy. However, it has been included in several clinical guidelines as a recommended non‐invasive testing procedure in dyspeptic patients.

Aim

To compare a monoclonal enzyme immunoassay for detection of H. pylori stool antigen (Amplified IDEIA HpStAR, DakoCytomation) with a polyclonal enzyme immunoassay (HpSA test, Premier Platinum HpSA, Meridian Diagnostics) in diagnosing infection and in determining H. pylori status after eradication treatment.

Methods

We evaluated stool samples of 198 patients diagnosed with H. pylori infection and of 41 patients without infection. The results of the monoclonal enzyme immunoassay HpStAR were compared with those of the polyclonal enzyme immunoassay HpSA.

Results

The sensitivity and specificity of HpStAR were 91.9% and 70.7%, while those of HpSA were 89.4% and 80.5%, respectively. In the 126 patients evaluated 6 weeks after eradication therapy, the overall agreement between urea breath test and HpStAR was 90.5% (P = 0.710) and between urea breath test and HpSA was 76.9% (P = 0.410).

Conclusions

HpStAR is a rapid and easy‐to‐perform test with similar sensitivity to HpSA in the diagnosis of H. pylori infection, although it had lower specificity. In contrast, HpStAR is more accurate after eradication therapy than HpSA.
Monocyte chemoattractant protein-1 (MCP-1) inhibits the intestinal-like differentiation of monocytes
Authors: Spoettl T , Hausmann M , Herlyn M , Gunckel M , Dirmeier A , Falk W , Herfarth H , Schoelmerich J , Rogler G
Published: June 2006

Monocytes (MO) migrating into normal, non-inflamed intestinal mucosa undergo a specific differentiation resulting in a non-reactive, tolerogenic intestinal macrophage (IMAC). Recently we demonstrated the differentiation of MO into an intestinal-like macrophage (MAC) phenotype in vitro in a three-dimensional cell culture model (multi-cellular spheroid or MCS model). In the mucosa of patients with inflammatory bowel disease (IBD) in addition to normal IMAC, a reactive MAC population as well as increased levels of monocyte chemoattractant protein 1 (MCP-1) is found. The aim of this study was to investigate the influence of MCP-1 on the differentiation of MO into IMAC. MCS were generated from adenovirally transfected HT-29 cells overexpressing MCP-1, macrophage inflammatory protein 3 alpha (MIP-3α) or non-transfected controls and co-cultured with freshly elutriated blood MO. After 7 days of co-culture MCS were harvested, and expression of the surface antigens CD33 and CD14 as well as the intracellular MAC marker CD68 was determined by flow-cytometry or immunohistochemistry. MCP-1 and MIP-3α expression by HT-29 cells in the MCS was increased by transfection at the time of MCS formation. In contrast to MIP-3α, MCP-1 overexpression induced a massive migration of MO into the three-dimensional aggregates. Differentiation of IMAC was disturbed in MCP-1-transfected MCS compared to experiments with non-transfected control aggregates, or the MIP-3α-transfected MCS, as indicated by high CD14 expression of MO/IMAC cultured inside the MCP-1-transfected MCS, as shown by immunohistochemistry and FACS analysis. Neutralization of MCP-1 was followed by an almost complete absence of monocyte migration into the MCS. MCP-1 induced migration of MO into three-dimensional spheroids generated from HT-29 cells and inhibited intestinal-like differentiation of blood MO into IMAC. It may be speculated that MCP-1 could play a role in the disturbed IMAC differentiation in IBD mucosa.
Effects of alveolar macrophage depletion on liposomal vaccine protection against respiratory syncytial virus (RSV)
Authors: Benoit A , Huang Y , Proctor J , Rowden G , Anderson R
Published: June 2006

Little is known about the identities and roles of antigen-presenting cells upon exposure to antigens of respiratory syncytial virus (RSV). Here, we focused on elucidating the importance of alveolar macrophages in conferring protective immunity in mice administered a liposome-encapsulated recombinant fragment of the RSV G protein. Mice were depleted of alveolar macrophages by intranasal inoculation of liposome-encapsulated dichloromethylenediphosphonic acid (DMDP). Mice depleted of alveolar macrophages prior to immunization developed reduced levels of serum RSV-neutralizing antibody and showed dramatically impaired protection against RSV challenge. The severity of interstitial inflammation was also markedly reduced in macrophage-depleted mice. In conclusion, this study demonstrates a pivotal role for alveolar macrophages during exposure to liposome-encapsulated RSV antigen in initiating both protective and histopathological responses against RSV.
Glucocorticoid metabolism within superficial subcutaneous rather than visceral adipose tissue is associated with features of the metabolic syndrome in South African women
Authors: Goedecke J. H. , Wake D. J. , Levitt N. S. , Lambert E. V. , Collins M. R. , Morton N. M. , Andrew R. , Seckl J. R. , Walker B. R.
Published: June 2006

Objective  Glucocorticoid hyperactivity in adipose tissue, due to up‐regulation of local glucocorticoid reactivation by 11β‐hydroxysteroid dehydrogenase‐1 (11HSD1) or of glucocorticoid receptors (GR), may underpin susceptibility to the metabolic syndrome. This hypothesis has been tested extensively in subcutaneous adipose tissue (SAT) but inadequately in visceral adipose tissue (VAT). The aim of the study was therefore to examine expression of 11HSD1, GRα and hexose‐6‐phosphate dehydrogenase (H6PDH), which supplies cofactor for 11HSD1, in abdominal adipose tissue compartments and to characterize their relation to metabolic syndrome parameters.

Design and subjects  A cross‐sectional study including 26 premenopausal South African women.

Measurements  Biopsies were taken for measurement of mRNA levels by real‐time polymerase chain reaction (RT‐PCR) and 11HSD1 activity from VAT, and deep and superficial SAT compartments during elective surgery. Prior to surgery, blood pressure, blood lipid profile, body composition [by dual X‐ray absorptiometry (DEXA) scan], body fat distribution [by computed tomography (CT) scan], and glucose tolerance were determined.

Results  11HSD1 activity (P < 0·01) was higher in VAT than SAT, but 11HSD1 and GRα mRNA levels were not statistically different between compartments. 11HSD1 mRNA levels in superficial SAT correlated with VAT volume (R = 0·57, P < 0·01), insulin sensitivity calculated from the oral glucose tolerance test (OGTT) (R = –0·52, P < 0·016) and blood pressure (R = 0·48, P < 0·016). Apart from a correlation between deep SAT 11HSD1 activity and blood pressure (R = 0·72, P < 0·01), glucocorticoid action in deep SAT and VAT depots was not significantly associated with any metabolic syndrome parameters.

Conclusion  Increased capacity for glucocorticoid regeneration in superficial SAT but not VAT is associated with visceral adiposity and other features of the metabolic syndrome in women.
Genetic features of the X chromosome affect pubertal development and testicular degeneration in adolescent boys with Klinefelter syndrome
Authors: Wikström Anne M. , Painter Jodie N. , Raivio Taneli , Aittomäki Kristiina , Dunkel Leo
Published: June 2006

Objective To investigate how genetic features of the X chromosome influence growth, pubertal development and testicular degeneration in adolescent boys with Klinefelter syndrome (KS). Previous studies have suggested that genetic features of the X chromosome may contribute to the wide phenotypic variation in KS.

Design A prospective clinical study.

Patients Fourteen nonmosaic 47,XXY boys, aged 10–13·9 years.

Measurements The relationship of genetic features of the X chromosome, including parental origin of X chromosomes, the CAG repeat length of the androgen receptor (AR) gene, and X inactivation with progression of pubertal development, growth and testicular function in KS boys.

Results Paternal (47,XmXpY,n = 3) as compared to maternal (47,XmXmY,n = 11) origin of the supernumerary X chromosome was associated with a later onset of puberty. In 47,XmXpY patients, serum LH concentrations increased above 1·0 IU/l at 12·5 ± 0·6 years (mean ± SD), Tanner stage P2 occurred at 12·5 ± 0·7 years, and pubertal acceleration of growth was noted at 13·9 ± 1·4 years and peak velocity at 14·5 ± 0·8 years. All of these occurred 1·3–1·9 years later than in 47,XmXmY patients (P = 0·01–0·09). In 47,XmXmY subjects, CAG repeat length (range 17–26) correlated with age at which serum LH level first exceeded 1·0 IU/l (rs = 0·63,P = 0·06,n = 10) and testosterone 1·0 nmol/l (28·8 ng/dl) (rs = 0·78,P = 0·02,n = 10).

Conclusions Paternal origin of the supernumerary X chromosome is associated with later onset of puberty and longer CAG repeats of theARwith later pubertal reactivation of the pituitary–testicular axis in KS boys. Identifying genetic factors that affect the phenotype may lead to a better understanding of the pathogenesis of KS.
Sleep apnoea and quality of life in growth hormone (GH)‐deficient adults before and after 6 months of GH replacement therapy
Authors: Peker Y. , Svensson J. , Hedner J. , Grote L. , Johannsson G.
Published: June 2006

Objective  To investigate the sleep architecture and breathing as well as quality of life (QoL) in adults with GH deficiency (GHD) before and 6 months after GH replacement therapy.

Design  A prospective observational study.

Patients  Nineteen consecutive adults with GHD (11 men, eight women; mean age 53, range 21–73 years) were studied.

Measurements  An overnight sleep study was performed and the Minor Symptom Evaluation Profile (MSEP), Functional Outcome of Sleep Questionnaire (FOSQ), Short Form 36 (SF‐36) and Epworth Sleepiness Scale (ESS) questionnaires were applied at baseline and after the treatment period.

Results  For the whole group, there were no significant changes in mean total sleep time (TST; 370 min vs. 374 min), proportion of slow‐wave sleep (SWS; 17·8%vs. 18·4%) and rapid eye movement (REM) sleep (12·1%vs. 13·9%) on GH replacement. Mean apnoea–hypopnoea index (AHI) was high and remained unchanged (28·2/h before vs. 28·0/h following GH replacement). Twelve patients (63%) were found to have obstructive sleep apnoea (OSA; AHI ≥ 10/h) at baseline. Compared with GH‐deficient patients without OSA (AHI 3·9/h), the OSA patients (AHI 42·4/h) had less SWS (11·4%vs. 28·6%, P = 0·010) and REM sleep (10·1%vs. 15·5%, P = 0·036). A marginal increase was observed in REM sleep time (10·1% before vs. 12·7% after GH; P = 0·048) while SWS was unchanged in this group. Moreover, MSEP for General Well‐being and Responsiveness, FOSQ scores for General Productivity, Activity Level and Vigilance as well as SF‐36 domains for Vitality and Mental Health were improved.

Conclusions  Contrary to some previous observations in a smaller group of patients, our data suggest that GH therapy does not induce or aggravate OSA in GH‐deficient adults. Moreover, GH therapy may improve some of the QoL dimensions in these patients.
Multiple endocrine neoplasia type 1 (MEN 1) is associated with an increased prevalence of diabetes mellitus and impaired fasting glucose
Authors: McCallum Roland W. , Parameswaran Venkat , Burgess John R.
Published: June 2006

Objective  Multiple endocrine neoplasia type 1 (MEN 1) is an autosomal dominant syndrome characterized by primary hyperparathyroidism, pituitary neoplasia and foregut lineage neuroendocrine tumours. It has also been associated with premature cardiovascular death. As diabetes is a risk factor for increased cardiovascular mortality we investigated the prevalence and clinical correlates of glycaemic abnormalities in a large MEN 1 kindred.

Patients and design  The glycaemic status of 72 MEN 1 affected and 133 unaffected members of a single large MEN 1 pedigree was assessed. Fasting glucose results were categorized and compared using WHO criteria. Associations between glycaemic status and MEN 1 phenotype were assessed.

Results  Thirteen (18·1%) patients with MEN 1 compared to 5 (3·8%) control patients were diabetic (P < 0·001). Six (8·3%) MEN 1 patients had impaired fasting glucose compared to 4 (3%) of controls (P < 0·05). Of patients with MEN 1, uncontrolled hypercalcaemia (P < 0·05) and elevated serum gastrin (P < 0·05) were more common amongst patients diagnosed with abnormal glycaemia than those with normoglycaemia. There was a nonsignificant trend for elevated chromogranin A, pancreatic polypeptide, gastric inhibitory polypeptide (but not glucagon) and history of bronchopulmonary carcinoid in MEN 1 patients with elevated glycaemia.

Conclusions  Diabetes and impaired fasting glucose occur significantly more frequently amongst MEN 1 patients than controls and is associated with uncontrolled hyperparathyroidism and evidence of enteropancreatic hyperstimulation.
Angiomatoid variant of fibrous histiocytoma: a case report and review of literature
Authors: PRATIBHA R. , AHMED S.
Published: June 2006

Summary.  Fibrous histiocytomas by themselves are not very common in the head and neck region. Apart from considering the above fact, this report describes a unique and relatively rare variant of the neoplasm – the angiomatoid fibrous histiocytoma (AFH) which has a characteristic appearance and predilection for young individuals that occurred in the left lower border of the mandible in a 13‐year‐old girl.

Angiomatoid fibrous histiocytoma is a distinct fibrohistiocytic tumour of children and young adults that combines features of both fibrohistiocytic and vascular neoplasm. It is considered to be a tumour of intermediate malignancy because of its less aggressive course in contrast to the conventional malignant fibrous histiocytoma. The authors would like to stress upon the fact that clinicians should not overlook swellings that may not appear distinct visually and therefore consider it to be a part of normal anatomy, dismiss it as an anomaly with no significance, or treat it injudiciously, for ultimately it may prove to be a tumour that would require appropriate treatment and follow‐up.
Aggressive periodontitis in a 16‐year‐old Ghanaian adolescent, the original source of Actinobacillus actinomycetemcomitans strain HK1651 – a 10‐year follow up
Authors: HAUBEK D. , HAVEMOSE‐POULSEN A. , WESTERGAARD J.
Published: June 2006

Summary.  The highly leukotoxic JP2 clone of Actinobacillus actinomycetemcomitans is strongly associated with periodontitis in adolescents. Availability of the DNA sequence of the complete genome of A. actinomycetemcomitans strain HK1651, a representative strain of the JP2 clone (http://www.genome.ou.edu/act.html), has provided new possibilities in basic research regarding the understanding of the pathogenesis of A. actinomycetemcomitans in periodontitis. This case report describes the periodontal treatment of the original source of A. actinomycetemcomitans HK1651, a 16‐year‐old Ghanaian adolescent girl with aggressive periodontitis. The bacterial examination involved polymerase chain reaction analysis for presence of JP2 and non‐JP2 types of A. actinomycetemcomitans. The treatment, including periodontal surgery supplemented by antibiotics, arrested the progression of periodontitis for more than 10 years. Initially, infection by A. actinomycetemcomitans, including the JP2 clone, was detected at various locations in the oral cavity and was not limited to the periodontal pockets. Post‐therapy, the JP2 clone of A. actinomycetemcomitans disappeared, while the non‐JP2 types of A. actinomycetemcomitans remained a part of the oral microflora.
Effect of enamel preparation method on in vitro marginal microleakage of a flowable composite used as pit and fissure sealant
Authors: YOUSSEF M. N. , YOUSSEF F. A. , SOUZA‐ZARONI W. C. , TURBINO M. L. , VIEIRA M. M. F.
Published: June 2006

Summary.  Objectives.  The aim of this in vitro study was to evaluate the microleakage in occlusal surfaces, after preparation with Er:YAG laser and compared to the diamond‐bur conventional technique.

Methods.  Thirty premolars were divided into three groups: I – high‐speed handpiece + 37% phosphoric acid; II – Er:YAG laser (350 mJ, 4 Hz and 112 J/cm2) + 37% phosphoric acid; and III – Er:YAG laser (350 mJ, 4 Hz and 112 J/cm2) + Er:YAG laser (80 mJ, 4 Hz, and 25 mJ/cm2). All cavities received the same adhesive system and were restored with flowable composite according to manufacturer's instructions. Teeth were submitted to thermal cycling and immersed in 50% silver nitrate solutions for 8 h in total darkness. Specimens were sectioned longitudinally in the bucco‐lingual direction, in slices of 1 mm thick. Each slice was immersed into photo developing solution and was photographed, and microleakage was scored from 0 to 7, by three calibrated examiners.

Results.  A statistically significant difference (P < 0·0001) was observed between Er:YAG laser prepared and etched specimens and those in the other groups.

Conclusions.  It can be concluded that no significant difference was noted between the two types of enamel preparation when etching was performed. Preparing and treating the enamel surface exclusively by Er:YAG laser resulted in the highest degree of leakage.
Asymmetric coexistence: bidirectional abiotic and biotic effects between goose barnacles and mussels
Authors: KAWAI TAKASHI , TOKESHI MUTSUNORI
Published: June 2006

Species coexistence depends on the net effect of interacting species, representing the sum of multiple interaction components that may act simultaneously and vary independently depending on ambient environmental conditions. Consequently, for a comprehensive understanding of the compound nature of species interactions and coexistence, a mechanistic approach that allows a separate evaluation of each interaction component is required.

Two sessile filter‐feeders, the goose barnacleCapitulum mitellaand the musselSeptifer virgatus, coexist on moderately wave‐exposed rocky shores in south‐western Japan. In the upper intertidal,Capitulumpositively influencedSeptifersurvivorship and growth through amelioration of thermal stress and of physical disturbance. On the other hand, these species are potential competitors as they have similar body sizes and modes of resource utilization. These opposite processes, facilitation and competition, are based on abiotic characteristics and biotic functions of the two species, respectively.

In order to quantify the bidirectional abiotic, biotic and net effects, a series of experimental manipulations was conducted involving the use of living neighbours with both abiotic and biotic effects, and artificial mimics to simulate abiotic effects without biotic effects.

Capitulumhad strong positive abiotic effects on the mussel survivorship in most experimental periods, while the biotic effect was negligible or weakly negative, suggesting that the net effect ofCapitulumon mussel survival was largely attributable to the abiotic effect. In contrast, a significantly negative biotic effect on the mussel growth rate was always present, though this was cancelled out by the larger, positive abiotic effect. In the case ofSeptifer, its abiotic and biotic effects on the survivorship of goose barnacles were negligible, while those on the growth rate showed temporal variation.

With respect to the relationship between species interaction and environmental conditions, the strength of abiotic facilitative effect ofCapitulumon mussel survival increased with increasing abiotic stress, while the strength of biotic effect was negligible or weakly negative. As regards the effects of mussels on goose barnacles, our study indicated no obvious relationship. These results point to the importance of decomposing interaction for an accurate, mechanistic understanding of species relations and coexistence.
Climate change and the origin of migratory pathways in the Swainson's thrush,Catharus ustulatus
Authors: Ruegg Kristen C. , Hijmans Robert J. , Moritz Craig
Published: June 2006

Aim To provide a spatially explicit model of how geographic distributions at the last glacial maximum (LGM) and post‐glacial colonization routes shaped current migratory pathways in the Swainson's thrush,Catharus ustulatus, a long‐distance migratory bird.

Location The Swainson's thrush breeds in boreal forest regions of the United States and Canada as well as in riparian woodlands along the Pacific coast of North America.

Methods Palaeodistribution modelling is combined with mtDNA phylogeography to predict the breeding range of the Swainson's thrush at the LGM. Quantitative environmental analysis and bioclimatic modelling are used to reconstruct the most likely post‐glacial colonization pathways. A maximum likelihood method for estimating growth rates is used to approximate the relative change in population size since the LGM.

Main conclusions The palaeodistribution models are concordant with the Swainson's thrush mtDNA phylogeography, suggesting that the inland and coastal groups were geographically isolated in eastern (inland) and western (coastal) regions at the LGM. Estimates of change in population size based on genetic data are remarkably consistent with estimates of change in range size, suggesting that the coastal group has undergone a 2‐ to 3‐fold demographic and range expansion, while the inland group has undergone a 6‐ to 12‐fold demographic and range expansion since the LGM. Bioclimatic analyses strongly support the hypothesis that populations expanding out of the east into previously glaciated areas in the west were undergoing a natural extension of their range by tracking the changes in climatic conditions. The combination of bioclimatic and molecular analyses is consistent with the idea that coastal and inland groups expanded from separate eastern and western regions after the LGM and that the current migratory pathway of the inland group retraces its post‐glacial colonization route.
The recent history and population structure of fiveMandarinasnail species from subtropical Ogasawara (Bonin Islands, Japan)
Authors: DAVISON ANGUS , CHIBA SATOSHI
Published: June 2006

The effect of Pleistocene climate change on the organisms of tropical and subtropical regions is rather poorly understood. We therefore studied the land snail genusMandarina(Bradybaenidae) of oceanic Ogasawara (Bonin Islands, Japan), with the aim of using population genetic data to understand their recent history. Our analysis of a mitochondrial 16S ribosomal RNA region from more than 600 snails in five ground‐living species suggests that populations on the small islands of Mukoujima, Anejima, Imotojima and Meijima, as well as on the low‐lying southern and central parts of Hahajima, have probably undergone recent bottlenecks followed by subsequent expansions. Except between the main island of Hahajima and Mukouijima, there is almost no evidence for gene flow among islands even though the islands were connected repeatedly by land bridges through the Pleistocene. Within islands the population structure is severe, suggestive of a long‐term, low level of gene flow (FSTis frequently greater than 0.5 among geographically close populations). Finally, there is a marked genetic patchiness, meaning that genetically close populations are sometimes separated by genetically distant populations. These patterns could be a consequence of expansion from bottlenecks, low active dispersal and founder effects caused by rare long‐distance migrants. Unfortunately, the exact nature of the refugia and bottlenecks remains unknown because the palaeoclimate of this region is poorly understood. Dating the population size changes is also challenging because the molecular clock is uncertain. We suggest, however, that arid conditions or deforestation induced by decreased atmospheric CO2may have been the main factor in determining population size.
The Aspergillus nidulans F‐box protein GrrA links SCF activity to meiosis
Authors: Krappmann Sven , Jung Nadja , Medic Branka , Busch Silke , Prade Rolf A. , Braus Gerhard H.
Published: June 2006

Cellular differentiation relies on precise and controlled means of gene expression that act on several levels to ensure a flexible and defined spatio‐temporal expression of a given gene product. In our aim to identify transcripts enriched during fruiting body formation of the homothallic ascomycete Aspergillus (Emericella) nidulans, the grrA gene could be identified in a negative subtraction hybridization screening procedure. It encodes a protein similar to fungal F‐box proteins, which function as substrate receptors for ubiquitin ligases, and that is highly related to the Saccharomyces cerevisiae regulatory protein Grr1p. Expression studies confirmed induction of grrA transcription and expression of its gene product during cleistothecial development of A. nidulans. Functional complementation of a yeast grr1Δ mutant was achieved by overexpression of the grrA coding sequence. A grrAΔ deletion mutant resembles the wild‐type in hyphal growth, asexual sporulation, Hülle cell formation or development of asci‐containing cleistothecia, but is unable to produce mature ascospores due to a block in meiosis as demonstrated by cytological staining of cleistothecial contents. Our results specify a particular involvement of the E3 ubiquitin ligase SCFGrrA in meiosis and sexual spore formation of an ascomyceteous fungus and shed light on the diverse functions of ubiquitin‐proteasome‐mediated protein degradation in eukaryotic development.
Identification of novel genomic islands coding for antigenic pilus‐like structures in Streptococcus agalactiae
Authors: Rosini Roberto , Rinaudo Cira Daniela , Soriani Marco , Lauer Peter , Mora Marirosa , Maione Domenico , Taddei Annarita , Santi Isabella , Ghezzo Claudia , Brettoni Cecilia , Buccato Scilla , Margarit Immaculada , Grandi Guido , Telford John L.
Published: June 2006

We have recently reported the presence of covalently linked pilus‐like structures in the human pathogen, Group B Streptococcus (GBS). The pilus operon codes for three proteins which contain the conserved amino acid motif, LPXTG, associated with cell wall‐anchored proteins together with two genes coding for sortase enzymes. Analysis of the eight sequenced genomes of GBS has led to the identification of a second, related genomic island of which there are two variants, each containing genes coding for proteins with LPXTG motifs and sortases. Here we show that both variant islands also code for pilus‐like structures. Furthermore, we provide a thorough description and characterization of the genomic organization of the islands and the role of each protein in the assembly of the pili. For each pilus, polymerization of one of the three component proteins is essential for incorporation of the other two proteins into the pilus structure. In addition, two sortases are required for complete pilus assembly, each with specificity for one of the pilus components. A component protein of one of the newly identified pili is also a previously identified protective antigen and a second component of this pilus is shown to confer protection against GBS challenge. We propose that pilus‐like structures are important virulence factors and potential vaccine candidates.
Origin inactivation in bacterial DNA replication control
Authors: Paulsson Johan , Chattoraj Dhruba K.
Published: June 2006

Initiation of DNA replication is a highly regulated process in all organisms. Proteins that are required to recruit DNA polymerase – initiator proteins – are often used to regulate the timing or frequency of initiation in the cell cycle by limiting either their own synthesis or availability. Studies of the Escherichia coli chromosome and of bacterial plasmids with iterated initiator binding sites (iterons) have revealed that, in addition to initiator limitation, replication origin inactivation is used to prevent replication that is untimely or excessive. Our recent studies of plasmid P1 revealed that this additional mode of control becomes a requirement when initiator availability is limited only by autoregulation. Thus, although initiator limitation appears to be a well‐conserved and central mode of replication control, optimal replication might require additional control mechanisms. This review gives examples of how the multiple mechanisms can act synergistically, antagonistically or be partially redundant to guarantee low frequency events. The lessons learned are likely to help understand many other regulatory systems in the bacterial cell.
Light activates the degradation of PIL5 protein to promote seed germination through gibberellin in Arabidopsis
Authors: Oh Eunkyoo , Yamaguchi Shinjiro , Kamiya Yuji , Bae Gabyong , Chung Won‐Il , Choi Giltsu
Published: June 2006

Angiosperm seeds integrate various environmental signals, such as water availability and light conditions, to make a proper decision to germinate. Once the optimal conditions are sensed, gibberellin (GA) is synthesized, triggering germination. Among environmental signals, light conditions are perceived by phytochromes. However, it is not well understood how phytochromes regulate GA biosynthesis. Here we investigated whether phytochromes regulate GA biosynthesis through PIL5, a phytochrome‐interacting bHLH protein, in Arabidopsis. We found that pil5 seed germination was inhibited by paclobutrazol, the ga1 mutation was epistatic to the pil5 mutation, and the inhibitory effect of PIL5 overexpression on seed germination could be rescued by exogenous GA, collectively indicating that PIL5 regulates seed germination negatively through GA. Expression analysis revealed that PIL5 repressed the expression of GA biosynthetic genes (GA3ox1 and GA3ox2), and activated the expression of a GA catabolic gene (GA2ox) in both PHYA‐ and PHYB‐dependent germination assays. Consistent with these gene‐expression patterns, the amount of bioactive GA was higher in the pil5 mutant and lower in the PIL5 overexpression line. Lastly, we showed that red and far‐red light signals trigger PIL5 protein degradation through the 26S proteasome, thus releasing the inhibition of bioactive GA biosynthesis by PIL5. Taken together, our data indicate that phytochromes promote seed germination by degrading PIL5, which leads to increased GA biosynthesis and decreased GA degradation.
Functionally redundant SHI family genes regulate Arabidopsis gynoecium development in a dose‐dependent manner
Authors: Kuusk Sandra , Sohlberg Joel J. , Magnus Eklund D. , Sundberg Eva
Published: June 2006

Gene duplication events, and the subsequent functional divergence of duplicates, are believed to be important evolutionary agents, driving morphological diversification. We have studied the structural and functional diversification of members of a plant‐specific gene family in Arabidopsis thaliana by analysing mutant phenotypes, expression patterns and phylogeny. The SHI gene family comprises ten members that encode proteins with a RING finger‐like zinc finger motif. We show that, despite being highly divergent in sequence, except in two conserved regions, many of the SHI‐related genes are partially redundant in function and synergistically promote gynoecium, stamen and leaf development in Arabidopsis. Gynoecia of the loss‐of‐function sty1‐1 mutant display subtle morphological defects, and, although mutations in the related STY2, SHI, SRS3, SRS4, SRS5, SRS7 and LRP1 genes have no apparent effect on gynoecium development, the sty1‐1 mutant phenotype is gradually enhanced in double, triple, quadruple and quintuple mutant combinations, suggesting a remarkably extensive functional conservation within the family, which appears to be based on dosage dependency and protection against dominant negative mutations. In multiple mutant lines, all marginal tissues in the apical part of the gynoecium are dramatically reduced or missing, and our data indicate that SHI family members may promote formation of these tissues downstream of the transcriptional co‐repressor LEUNIG (LUG).
Adverse side‐effects to biological agents
Authors: Pichler W. J.
Published: June 2006

Biological agents‐like cytokines, monoclonal antibodies and fusion proteins are widely used in anti‐inflammatory and tumour therapy. They are highly efficient in certain diseases, but can cause a great variety of adverse side‐effects. Based on the peculiar features of biological agents a new classification of these adverse side‐effects of biological agents is proposed – related but clearly distinct from the classification of side‐effects observed with chemicals and drugs. This classification differentiates five distinct types, namely clinical reactions because of high cytokine levels (typeα), hypersensitivity because of an immune reaction against the biological agent (β), immune or cytokine imbalance syndromes (γ), symptoms because of cross‐reactivity (δ) and symptoms not directly affecting the immune system (ɛ). This classification could help to better deal with the clinical features of these side‐effects, to identify possible individual and general risk factors and to direct research in this novel area of medicine.
Comparison of two methods for exhaled breath condensate collection
Authors: Soyer O. U. , Dizdar E. A. , Keskin O. , Lilly C. , Kalayci O.
Published: June 2006

Background:  Exhaled breath condensate (EBC) is a noninvasive method to obtain samples from fluids lining the respiratory surfaces. Even though various methods and devices are now available, the relative efficiency of these methods for recovering airway mediators and characterizing EBC has not been established.

Aim:  To compare the volume, pH, lipid mediator, and protein concentrations in EBCs collected by two commonly used commercially available devices, RTubeTM and ECoScreen.

Methods:  Exhaled breath condensates were obtained consecutively using the RTubeTM and ECoScreen methods from 30 healthy, nonallergic adults. Samples were immediately placed on dry ice after collection. pH was measured after argon deaeration. Cysteinyl leukotrienes (cys‐LTs) were measured as a representative lipid mediator and eotaxin as the protein mediator by using enzyme‐linked immunosorbent assay.

Results:  The mean volume of samples obtained with ECoScreen (1880 ± 116 μl) was significantly higher than that obtained with RTubeTM (1405 ± 82 μl) (P < 0.001). Concentrations of both cys‐LTs [205.4 pg/ml (65.5–472.3) with ECoScreen vs 21.6 (11.87–152.2) with RTubeTM, P < 0.001] and eotaxin [17.0 pg/ml (11.4–22.4) with ECoScreen vs 11.7 (10.5–13.5) with RTubeTM, P = 0.01] were significantly higher in samples collected with ECoScreen than with RTubeTM. There was no significant difference between the pH measurements.

Conclusion:  Compared with RTubeTM, collection of exhaled breath by ECoScreen allows larger volumes to be collected and detects protein and lipid mediators with greater sensitivity. These differences in mediator recovery may be due to the differences in the collection temperature.
Meal Size Effects on Antipredator Behavior of Hatchling Trinket Snakes, Elaphe helena
Authors: Mehta Rita S.
Published: June 2006

Current foraging models limit the decision‐making process of animals to the food searching and consuming phase. The post‐consummatory phase of feeding may influence optimal meal size for some species as a morphologic change often results from feeding. In snakes, a single prey item can lead to abrupt increases in body mass, thus influencing locomotor performance. Identifying factors affecting locomotor performance can help predict behaviors that should maximize an animal's chance of evading predators. Although many snakes ingest large percentages of their body mass, not much work has examined the post‐consummatory effects of ingesting bulky prey differing in relative mass. I examined the locomotor performance and antipredator tactics of hatchling trinket snakes (Elaphe helena) after subjecting snakes to mice prey varying by relative mass differences of 20–35%, 50–59% or 70–79% of an individual hatchling's body mass. Snakes in treatment groups were compared with snakes in a control group (0%). Meal size‐affected locomotor parameters such as burst speed, endurance, and endurance times for hatchlings that ingested 50–59% and 70–79% of their body mass (p < 0.001). Recent feeding also affected the types of antipredator modes employed. Hatchlings in the 0% and 20–35% treatments exhibited behaviors that were categorized as active and threatening, while hatchlings in the 50–59% and 70–79% treatments exhibited stationary, neutral, and cryptic behaviors. Although snakes may become more reclusive following a meal, this study demonstrates that relative prey mass affects the ability of hatchling trinket snakes to flee from a predator. In turn, these results suggest that the post‐consummatory effects of foraging should be considered in optimal foraging models for organisms that consume a substantial portion of their body mass during a single feeding.
Treatment of isolated systolic hypertension in diabetes mellitus type 2
Authors: Os Ingrid , Gudmundsdottir Helga , Kjeldsen Sverre E. , Oparil Suzanne
Published: June 2006

Age‐related arterial stiffness is more pronounced in diabetics compared to non‐diabetics, which could explain the prevalence of isolated systolic hypertension (ISH, systolic blood pressure ≥140 mmHg and diastolic blood pressure <90 mmHg) being approximately twice that of the general population without diabetes. Large‐scale interventional outcome trials have also shown that diabetics usually have higher pulse pressure and higher systolic blood pressure than non‐diabetics. Advanced glycation end‐product formation has been implicated in vascular and cardiac complications of diabetes including loss of arterial elasticity, suggesting possibilities for new therapeutic options. With increasing age, there is a shift to from diastolic to systolic blood pressure and pulse pressure as predictors of cardiovascular disease. This may affect drug treatment as different antihypertensive drugs may have differential effects on arterial stiffness that can be dissociated from their effects on blood pressure. While thiazide diuretics are associated with little or no change in arterial stiffness despite a robust antihypertensive effect, angiotensin converting enzyme inhibitors, angiotensin II receptor blockers and calcium‐channel blockers have been shown to reduce arterial stiffness. However, combination therapy is nearly always necessary to obtain adequate blood pressure control in diabetics. There are no randomized controlled trials looking specifically at treatment of ISH in diabetics. Recommendations regarding treatment of ISH in diabetes mellitus type 2 are based on extrapolation from studies in non‐diabetics, post‐hoc analyses and prespecified subgroup analysis in large‐scale studies, and metaanalysis. These analyses have clearly demonstrated that blood pressure lowering in ISH confers improved prognosis and reduced cardiovascular and renal outcomes in both diabetics and non‐diabetics.
RESEARCH AND DEVELOPMENT IN SMALL AND MEDIUM‐SIZED ENTERPRISES: THE ROLE OF FINANCIAL CONSTRAINTS AND PUBLIC FUNDING
Authors: Czarnitzki Dirk
Published: June 2006

This paper presents microeconometric evidence on financing constraints for research and development activities in German small‐ and medium‐sized firms (SME). Special attention is paid to the role of public research and development (R&D) subsidies. For this purpose SMEs in West and East Germany are compared because these regions are very different in their supply of public R&D funding. The empirical evidence suggests that West German SMEs are financially constrained in their R&D activities by both internal and external resources. In East Germany, firms are not sensitive to external constraints, possibly due to high public R&D subsidies. The results show that R&D in East Germany is to a large extent driven by public subsidies and that the usual financial market mechanisms are dysfunctional with respect to R&D in this region.
U.S. Supreme Court Decision Making, Case Salience, and the Attitudinal Model
Authors: UNAH ISAAC , HANCOCK ANGE‐MARIE
Published: June 2006

Does case salience condition the role of ideological preferences in the decisions of U.S. Supreme Court justices? Does the attitudinal model of judicial behavior hold equally true in high salience and low salience cases? In this article, we analyze the role of case salience as a moderating influence on the explanatory capacity of the attitudinal model and test the strength of the model in high salience versus low salience contexts. Using civil rights votes during forty‐seven Supreme Court terms, from 1953 through 2000, we find that the attitudinal model is sensitive to case salience and that justices rely significantly more on ideological preferences when deciding high salience cases than low salience ones. Our findings represent an important qualification to the attitudinal model.