bluuebunny/crossref_metadata_2025 huggingface dataset:
Long‐term treatment of gastro‐oesophageal reflux disease patients with frequent symptomatic relapses using rabeprazole: on‐demand treatment compared with continuous treatment
Authors: Bour B. , Staub J.‐L. , Chousterman M. , Labayle D. , Nalet B. , Nouel O. , Pariente A. , Tocque E. , Bonnot‐Marlier S.
Published: March 2005

Background : On‐demand treatment may be an alternative in the long‐term treatment of non‐severe gastro‐oesophageal reflux disease in patients with frequent symptomatic relapses.

Aim : To compare the efficacy of on‐demand treatment with rabeprazole 10 mg versus continuous treatment in the long‐term treatment of patients with frequent symptomatic relapses of mild to moderate gastro‐oesophageal reflux disease.

Methods : This randomized, open‐label study enrolled patients diagnosed with non‐erosive reflux disease or oesophagitis grade 1 or 2 (Savary–Miller classification) reporting frequent symptomatic relapses (requiring ≥2 courses of antisecretory therapy during the previous year), whose intensity is rated at least moderate (>2 on a 5‐point Likert scale). After a 4‐week selection phase with rabeprazole 10 mg once daily, patients reporting symptom relief (Likert score ≤2) were randomized to receive either rabeprazole 10 mg continuous treatment or on‐demand treatment for 6 months. The main evaluation criterion was the rate of symptom relief (scored on the Likert scale) after 6 months.

Results : One hundred and seventy‐six patients were enrolled in the 4‐week selection phase (men, 53%; mean age, 49 years; non‐erosive reflux disease, 36.4%; gastro‐oesophageal reflux disease 1, 53.4%; gastro‐oesophageal reflux disease 2, 10.2%). Rabeprazole relieved symptoms in 88.6% of patients. Of this group, 152 were randomized to the comparative phase to receive rabeprazole 10 mg continuous treatment (once daily) or on‐demand treatment (continuous treatment, n = 81; on‐demand treatment, n = 71). At month 6 (end point), the symptom relief rate was slightly higher for patients in the continuous treatment group compared with those in the on‐demand treatment group: 86.4% versus 74.6%, respectively. This difference was not statistically significant (P = 0.065). For the overall quality of life score, there was no difference between the continuous treatment and on‐demand treatment groups (86.25 and 84.94). Mean daily consumption of rabeprazole was significantly lower in the on‐demand treatment group versus the continuous treatment group (0.31 tablets versus 0.96 tablets; P < 0.0001).

Conclusion : On‐demand therapy with rabeprazole 10 mg provides an alternative to continuous therapy in patients with mild to moderate gastro‐oesophageal reflux disease suffering from frequent symptomatic relapses.
Systematic review and meta‐analysis: is 1‐week proton pump inhibitor‐based triple therapy sufficient to heal peptic ulcer?
Authors: Gisbert J. P. , Pajares J. M.
Published: March 2005

Aims : To systematically review the efficacy on ulcer healing of 1‐week combination of a proton pump inhibitor plus two antibiotics and to perform a meta‐analysis of randomized clinical trials to evaluate whether 7 days of proton pump inhibitor‐based triple therapy is sufficient to heal peptic ulcer.

Methods : Studies where 1‐week proton pump inhibitor‐based triple therapy was administered to heal peptic ulcer were included. Randomized clinical trials comparing the efficacy on ulcer healing of 7‐day proton pump inhibitor‐based triple therapy versus this same regimen but prolonging the proton pump inhibitor for several more weeks were included in the meta‐analysis. Electronic and manual bibliographical searches were conducted. Meta‐analysis was performed combining the odds ratios of the individual studies.

Results : Twenty‐four studies (2342 patients) assessed ulcer healing with 1‐week proton pump inhibitor‐based triple therapy. Mean healing rate was 86%, and 95% in Helicobacter pylori‐eradicated patients. Six studies (862 patients), were included in the meta‐analysis. Mean ulcer healing rate with a 7‐day treatment was 91% versus 92% when proton pump inhibitor was prolonged for 2–4 more weeks (odds ratio = 1.11; 95% confidence interval = 0.71–1.74).

Conclusion : In patients with peptic ulcer and H. pylori infection, prolonging therapy with proton pump inhibitor after a triple therapy for 7 days with a proton pump inhibitor and two antibiotics is not necessary to induce ulcer healing.
A phase 2 clinical trial of metformin as a treatment for non‐diabetic paediatric non‐alcoholic steatohepatitis
Authors: Schwimmer J. B. , Middleton M. S. , Deutsch R. , Lavine J. E.
Published: March 2005

Background : Children with non‐alcoholic steatohepatitis are insulin‐resistant and metformin has been proposed as a potential therapy. However, paediatric safety and efficacy data are absent.

Aim : To test the hypothesis that metformin therapy will safely improve markers of liver disease in paediatric non‐alcoholic steatohepatitis.

Methods : Single‐arm open‐label pilot study of metformin 500 mg twice daily for 24 weeks in non‐diabetic children with biopsy‐proven non‐alcoholic steatohepatitis.

Results : Ten obese children (mean body mass index 30.4) enrolled and completed the trial. Mean alanine aminotransferase and aspartate aminotransferase (AST) improved significantly (P < 0.01) from baseline (184, 114 U/L) to end of treatment (98, 68 U/L). Alanine aminotransferase normalized in 40% and AST normalized in 50% of subjects. Children demonstrated significant improvements in liver fat measured by magnetic resonance spectroscopy (30–23%, P < 0.01); insulin sensitivity measured by quantitative insulin sensitivity check index (0.294–0.310, P < 0.05); and quality of life measured by pediatric quality of life inventory 4.0 (69–81, P < 0.01).

Conclusion : Open‐label treatment with metformin for 24 weeks was notable for improvement in liver chemistry, liver fat, insulin sensitivity and quality of life. A large randomized‐controlled trial is needed to definitively determine the efficacy of metformin for paediatric non‐alcoholic steatohepatitis.
Missing gastric cancer in dyspepsia
Authors: Schmidt N. , Peitz U. , Lippert H. , Malfertheiner P.
Published: March 2005

Background : Dyspepsia is common in gastric cancer, but also in many benign conditions. European Helicobacter pylori Study Group and American Gastroenterological Association guidelines recommend endoscopy in dyspepsia for patients with alarm symptoms or at age >45 years. However, recommendations are controversial.

Aim : To investigate whether criteria for endoscopy in patients with dyspepsia are adequate to detect gastric cancer.

Methods : In 215 patients at initial diagnosis of gastric adenocarcinoma, symptoms were classified as alarm and non‐alarm. Cases were staged according to the TNM system. Stages T1–T3NxM0 were defined as potentially curable.

Results : Dyspepsia was present in 128 patients. Among patients with dyspepsia, 15 were ≤45 years and 41 denied alarm symptoms. The combination of both criteria excluded only three (2.3%) patients from endoscopy, but increasing the threshold to >50 and >55 years would have raised the rate of excluded patients to seven (5.5%) and 11 (8.6%). Only 53 potentially curable stages and 18 early gastric cancers occurred, but the tumour stage was not associated with dyspepsia duration, age threshold of 45 years, or alarm symptoms.

Conclusions : Our results support current European Helicobacter Study Group and American Gastroenterological Association criteria for endoscopy in patients with dyspepsia to detect gastric cancer. Regardless, most cancers are advanced at detection.
Proportion of various types of thyroid disorders among newborns with congenital hypothyroidism and normally located gland: a regional cohort study
Authors: Gaudino Rossella , Garel Catherine , Czernichow Paul , Léger Juliane
Published: March 2005

Objective  To determine the proportion of the various types of thyroid disorders among newborns detected by the neonatal TSH screening programme, with a normally located thyroid gland.

Patients and methods  Of the 882 575 infants screened in our centre between 1981 and 2002, 85 infants with a normally located gland had persistent elevation of serum TSH values (an incidence of 1/10 383). Six of these 85 patients were lost to follow‐up and were therefore excluded from the study. During follow‐up, patients were classified as having permanent or transient hypothyroidism.

Results  Among the 79 patients included in the study, transient (n = 30, 38% of cases) and permanent (n = 49, 62% of cases) congenital hypothyroidism (CH) was demonstrated during the follow‐up at the age of 0·7 ± 0·6 years and 2·6 ± 1·8 years (P < 0·0001), respectively. The proportion of premature births was significantly higher in the group with transient CH (57%) than in the group with permanent CH (2%) (P < 0·0001). A history of iatrogenic iodine overload was identified during the neonatal period in 69% of transient cases. Among permanent CH cases (n = 49), patients were classified as having a goitre (n = 27, 55% of cases), a normal sized and shaped thyroid gland (n = 14, 29% of cases) or a hypoplastic gland (n = 8, 16% of cases). The latter patients demonstrated global thyroid hypoplasia (n = 3), a right hemithyroid (n = 2), hypoplasia of the left lobe (n = 2), or asymmetry in the location of the two lobes (n = 1). Patients with a normal sized and shaped thyroid gland showed a significantly less severe form of hypothyroidism than those with a goitre or a hypoplastic thyroid gland (P < 0·0002). Among permanent CH cases, those with a goitre (n = 27) had an iodine organification defect (n = 10), Pendred syndrome (n = 1), a defect of thyroglobulin synthesis (n = 8), or a defect of sodium iodine symporter (n = 1), and in seven patients no aetiology could be determined. Among permanent cases with a normal sized and shaped thyroid gland (n = 14), a specific aetiology was found in only one patient (pseudohypoparathyroidism) and two patients had Down's syndrome. Among those with a globally hypoplastic gland, a TSH receptor gene mutation was found in two patients.

Conclusions  A precise description of the phenotype can enhance our understanding of various forms of neonatal hypothyroidism as well as their prevalence and management. It also helps to identify cases of congenital hypothyroidism of unknown aetiology, which will need to be investigated in collaboration with molecular biologists.
Supraphysiological growth hormone: less fat, more extracellular fluid but uncertain effects on muscles in healthy, active young adults
Authors: Ehrnborg Christer , Ellegård Lars , Bosaeus Ingvar , Bengtsson Bengt‐Åke , Rosén Thord
Published: March 2005

Objectives  To study the effects on body composition after 1 month's administration of supraphysiological doses of growth hormone (GH) in healthy, active young adults with normal GH‐IGF‐I axis.

Subjects and methods  Thirty healthy, physically active volunteers (15 men and 15 women), mean age 25·9 years (range 18–35), participated in this study, designed as a randomized, double‐blind, placebo‐controlled, parallel study with three groups (n = 10: five men and five women in each group). The groups comprised the following: placebo (P), GH 0·1 IU/kg/day [0·033 mg/kg/day] (GH 0·1) and GH 0·2 IU/kg/day [0·067 mg/kg/day] (GH 0·2).

Results  In the pooled group with active GH treatment (n = 20) the results showed significant increases: IGF‐I increased by 134% (baseline vs. after 1 month), body weight by 2·7%, fat free mass by 5·3%, total body water by 6·5% and extracellular water (ECW) by 9·6%. Body fat decreased significantly by 6·6%. No significant change in intracellular water was detected. The observed increase in fat free mass by 5·3% was explained by the ECW increase, indicating limited anabolic effects of the supraphysiological GH doses. Changes were noticeable in both genders, although more prominent in the male subjects. Fluid retention symptoms occurred in the majority of individuals.

Conclusions  This is, to our knowledge, the first placebo‐controlled trial to show the effects of supraphysiological GH doses on body composition and IGF‐I levels in physically active and healthy individuals of both genders; the results indicate limited anabolic effects of GH with these supraphysiological doses. The role of GH as an effective anabolic doping agent is questioned.
Growth hormone replacement reduces C‐reactive protein and large‐artery stiffness but does not alter endothelial function in patients with adult growth hormone deficiency
Authors: McCallum Roland W. , Sainsbury Christopher A. R. , Spiers Angela , Dominiczak Anna F. , Petrie John R. , Sattar Naveed , Connell John M. C.
Published: March 2005

Hypopituitary patients have an increased risk of vascular mortality that may relate to growth hormone deficiency (GHD). We investigated the effects of 6 months of GH therapy on large‐ and small‐artery function and high‐sensitivity C‐reactive protein (hsCRP) in a cohort of GH‐deficient patients. Sixteen hypopituitary patients were randomized to 6 months of GH therapy or no treatment, then vice versa. hsCRP, 24‐h blood pressure (BP) and pulse wave velocity (PWV) were measured and resistance arteries were used to construct concentration–response curves to endothelium‐dependent and ‐independent agents. GH therapy increased IGF‐1 from 60 ± 7·2 to 167 ± 16·2 µg/l [confidence interval (CI) 94·9, 138·8, P < 0·001]. hsCRP declined after 6 months of GH from 3·8 ± 0·88 to 2·0 ± 0·49 mg/l (CI 0·73, 3·57, P = 0·006). Mean arterial BP fell from 91·7 ± 1·5 to 89·3 ± 1·2 mmHg (CI 0·81, 4·07, P = 0·005), as did PWV (8·1 ± 0·4 to 6.7 ± 0·5 m/s). The decline in PWV correlated with the decline in hsCRP (r = 0·68, P = 0·01). Resistance artery function was unchanged after GH therapy. GH replacement may lead to differentially altered production of vasorelaxant agents from the endothelium of large and small arteries. Reduction in vascular inflammation may be associated with reduced vascular risk.
Serum levels of sex hormone‐binding globulin (SHBG) are not associated with lower levels of non‐SHBG‐bound testosterone in male newborns and healthy adult men
Authors: De Ronde Willem , Van Der Schouw Yvonne T. , Pierik Frank H. , Pols Huibert A. P. , Muller Majon , Grobbee Diederick E. , Gooren Louis J. G. , Weber Rob F. A. , De Jong Frank H.
Published: March 2005

Objective   It is generally accepted that SHBG decreases the bioavailability and activity of testosterone (T). In in vitro experiments increased levels of SHBG will be associated with decreased levels of non‐SHBG bound testosterone (non‐SHBG‐T). However, in vivo SHBG can alter both production and clearance rates and thus plasma levels of T.

Design and patients   In order to study the effect of SHBG on the levels of non‐SHBG‐T in vivo in the presence of an active hypothalamo–pituitary–gonadal (HPG) axis we conducted a cross sectional study in 400 healthy adult men with an age range of 40–80 years and in 106 newborn boys.

Measurements   In both groups, regression coefficients (β) and partial correlation coefficients (r) were calculated for the relationship between SHBG and T or non‐SHBG‐T. Adult men were divided into age groups per decade (40–50 years, 51–60 years, 61–70 years and 71–80 years) to study possible differences in the impact of SHBG on the level of non‐SHBG‐T throughout ageing.

Results   Higher levels of SHBG were associated with higher levels of total testosterone in neonates (β = 0·02 ± 0·004, r = 0·44, P < 0·001) but not with non‐SHBG‐T (β = −0·001 ± 0·001, r = 0·05, P = 0·52). In adult men there was a significant age related increase in levels of SHBG and an age‐related decrease of both total and non‐SHBG‐T. Higher SHBG was strongly associated with higher total testosterone in all age groups (β = 0·26, 0·26, 0·26 and 0·23 for 40–50 years, 51–60 years, 61–70 years and 71–80 years, respectively, P < 0·001 for all age groups). Higher SHBG was not or only slightly associated with higher non‐SHBG‐T β = 0·02 (P = 0·32), β = 0·04 (P = 0·03), β = 0·04 (P = 0·02) and β = 0·02 (P = 0·16) for 40–50 years, 51–60 years, 61–70 years and 71–80 years, respectively.

Conclusions   In contrast to general belief, SHBG levels barely influence levels of non‐SHBG‐bound testosterone both in male newborns and healthy adult men: the influence, if any, is positive. Consequently the age related increase of SHBG does not account for the age related decline in non‐SHBG‐T in healthy adult men.
The expression of messenger RNA for ADP‐ribosyl cyclase in aldosterone‐producing adenomas
Authors: Takeda Yoshiyu , Usukura Mikiya , Yoneda Takashi , Oda Nobushige , Ito Yoko , Mabuchi Hiroshi
Published: March 2005

Objective  Cyclic ADP‐ribose (cADPR) has been reported to be as potent and powerful at releasing intracellular Ca2+ as inositol triphosphate (IP3). To determine whether the cADPR system plays a signalling role in angiotensin II (Ang II)‐induced aldosterone synthesis in the human adrenal gland, we investigated the effects of Ang II on ADP‐ribosyl cyclase activity in human adrenal cortical tissue. In addition, the expression of ADP‐ribosyl cyclase messenger RNA was evaluated in aldosterone‐producing adenomas (APAs) and compared with normal adrenal tissue and nonfunctioning adenomas.

Design  ADP‐ribosyl cyclase activity was measured in crude membrane fractions of human adrenocortical tissues with Ang II or with Ang II plus the Ang II receptor (AT1R) antagonist losartan or plus the AT2R antagonist PD123319. The effect of 8‐bromo‐cADPR on Ang II‐induced aldosterone production from adrenal tissue was estimated. The expression of ADP‐ribosyl cyclase, CYP11B2 and AT1R mRNA was measured in APAs, nonfunctioning adenomas, adjacent adrenal tissue and normal adrenal tissue.

Measurements  ADP‐ribosyl cyclase activity was measured by using high‐performance liquid chromatography (HPLC) and [3H] NAD+. mRNA expression was measured by competitive reverse‐transcription polymerase chain reaction (RT‐PCR).

Results  Ang II (10−7 and 10−8 mol/l) significantly increased ADP‐ribosyl cyclase activity in a dose‐dependent manner. This increase was inhibited by pretreatment with losartan but not with PD123319. Treatment with 8‐bromo‐cADPR (50 µmol/l) reduced Ang II‐induced aldosterone secretion. ACTH did not significantly increase the enzyme activity. The expression of ADP‐ribosyl cyclase, CYP11B2 and AT1R mRNA was increased in APAs compared with that of nonfunctioning adenomas, adjacent adrenal tissue or normal adrenal tissue.

Conclusions  These results demonstrated the existence of a signalling pathway from the Ang II receptor to ADP‐ribosyl cyclase in the human adrenal gland and suggest that the cADP‐ribose signalling system might play an important role in the pathogenesis of APAs.
Herbivory, time since introduction and the invasiveness of exotic plants
Authors: CARPENTER DAVID , CAPPUCCINO NAOMI
Published: March 2005

We tested the enemy release hypothesis for invasiveness using field surveys of herbivory on 39 exotic and 30 native plant species growing in natural areas near Ottawa, Canada, and found that exotics suffered less herbivory than natives.

For the 39 introduced species, we also tested relationships between herbivory, invasiveness and time since introduction to North America. Highly invasive plants had significantly less herbivory than plants ranked as less invasive. Recently arrived plants also tended to be more invasive; however, there was no relationship between time since introduction and herbivory.

Release from herbivory may be key to the success of highly aggressive invaders. Low herbivory may also indicate that a plant possesses potent defensive chemicals that are novel to North America, which may confer resistance to pathogens or enable allelopathy in addition to deterring herbivorous insects.
Pre‐dispersal predation of Taraxacum officinale (dandelion) seed
Authors: HONEK ALOIS , MARTINKOVA ZDENKA
Published: March 2005

Pre‐dispersal predation of seeds of Asteraceae has been studied in species where ripening seed is present on plants for long periods but rarely in those where seed maturation is ephemeral and density of consumers is therefore unlikely to keep pace with changes in seed availability.

We therefore followed predation of dandelion (Taraxacum officinale) seeds by the larvae of Glocianus punctiger and Olibrus bicolor and predicted that both abundance of seed consumers and seed damage will be indirectly proportional to inflorescence availability, and that overall seed damage will be less than in species with longer lived inflorescences.

We counted the number of dandelion capitula m−2, number of larvae capitulum−1 and percentage of damaged seeds at 10 sites, where the flowering time and densities of dandelions differed. The counts were made in 2002 and 2003, at half‐weekly (April–May) or weekly (June–August) intervals.

Abundance of both species of consumer varied among dandelion patches, and with change in availability of dandelion capitula. Numbers of larvae capitulum−1 were high early and late, when few capitula were available, but decreased at the time of peak flowering when there were many capitula. Production of ready‐to‐pupate larvae m−2 of a species at a site was similar in successive years, but values for O. bicolor and G. punctiger were not correlated.

Seed damage paralleled the abundance of consumer larvae, with early and late flowers suffering most. A linear relationship correcting for lost seeds, predicted 30% damage when there were five larvae capitulum−1, below levels reported for species of Asteraceae with persistent inflorescences.

The intensity of pre‐dispersal seed predation is directly proportional to the abundance of seed consumer species and indirectly proportional to the availability of maturing capitula. Consequently, in species with ephemeral, synchronized flowering, where seed is available for only a short time, the majority of plants lose only a small proportion to predators. Although those flowering earlier or later than the peak will suffer a much higher risk, the low overall level of damage is unlikely to influence population biology.
The Human MT1 Melatonin Receptor Stimulates cAMP Production in the Human Neuroblastoma Cell Line SH‐SY5Y Cells Via a Calcium‐Calmodulin Signal Transduction Pathway
Authors: Schuster C. , Williams L. M. , Morris A. , Morgan P. J. , Barrett P.
Published: March 2005

Melatonin regulates circadian and seasonal physiology via melatonin receptors expressed in the brain. However, little is known about the signal transduction mechanisms that mediate the action of melatonin in neuronal cells. To begin to address this issue, we expressed the human MT1 receptor in the human neuroblastoma SH‐SY5Y cell line. In this cell line, melatonin acutely stimulated cAMP synthesis through a calcium‐calmodulin dependent pathway. This stimulatory effect was independent of an interaction with Gi or Gs G proteins and dependent upon internal calcium stores. Melatonin also potentiated forskolin‐activated cAMP synthesis. Differentiation of the neuroblastoma cells with retinoic acid to the neuronal phenotype did not alter the ability of melatonin to acutely stimulate cAMP. These data may be relevant to the neuronal action of melatonin and highlight the importance of the cellular context of expression of melatonin and other G protein‐coupled receptors.
Oestrogen and Testosterone Modulate the Firing Activity of Dorsal Raphe Nucleus Serotonergic Neurones in Both Male and Female Rats
Authors: Robichaud M. , Debonnel G.
Published: March 2005

Women are twice as likely to suffer from mood disorders than men. Moreover, a growing body of evidence suggests a reciprocal modulation between sex steroids and the serotonin (5‐HT) system. A previous study from our laboratory has shown that the progesterone metabolites 5β‐pregnane‐3,20‐dione (5β‐DHP) and 5α‐pregnan‐3α‐ol,20‐one (3α,5α‐THP), as well as dehydroepiandrosterone (DHEA), increase the firing activity of dorsal raphe nucleus (DRN) 5‐HT neurones in female rats. The present study was undertaken to assess the effects of these steroids in male rats, as well as the effects of testosterone and 17β‐oestradiol (17β‐E) in both sexes, and finally to evaluate gender differences in the modulation of the 5‐HT neuronal firing activity by these different neuroactive steroids. Male rats were treated i.c.v., for 7 days, with a dose of 50 µg/kg/day of one of the following steroids: progesterone, 5β‐DHP, 3α,5α‐THP, DHEA, testosterone, 17β‐hydroxy‐5α‐androstan‐3‐one (5α‐DHT) and 17β‐E. Some rats also received a 3‐day administration of testosterone (50 µg/kg/day, i.c.v). Females were treated in the same fashion with testosterone and 17β‐E. Extracellular unitary recordings of 5‐HT neurones, obtained in vivo in the DRN of these rats, revealed that testosterone and 17β‐E increased the firing activity of 5‐HT neurones in both males and females. In males, the effect of testosterone could already be seen after 3 days of treatment. Neither castration nor any treatment with other steroids significantly modified the firing rate of male 5‐HT neurones. Taken together with previous findings, the results of the present study indicate both similarities and differences between sexes in the modulation of 5‐HT neurones by some steroids. This could prove important in understanding gender differences in mood disorders.
The unique structure of archaeal ‘hami’, highly complex cell appendages with nano‐grappling hooks
Authors: Moissl Christine , Rachel Reinhard , Briegel Ariane , Engelhardt Harald , Huber Robert
Published: March 2005

Proteinaceous, hair‐like appendages known as fimbriae or pili commonly extend from the surface of prokaryotic cells and serve important functions such as cell adhesion, biofilm formation, motility and DNA transfer. Here we show that a novel group of archaea from cold, sulphidic springs has developed cell surface appendages of an unexpectedly high complexity with a well‐defined base‐to‐top organization. It represents a new class of filamentous cell appendages, for which the term ‘hamus’ is proposed. Each archaeal cell is surrounded by a halo of about 100 hami, which mediate strong adhesion of the cells to surfaces of different chemical composition. The hami are mainly composed of 120 kDa subunits and remained stable in a broad temperature and pH range (0–70°C; 0.5–11.5). Electron microscopy and cryo‐electron tomography revealed that the hamus filament possesses a helical basic structure. At periodic distances, three prickles emanate from the filament, giving it the character of industrially produced barbwire. At its distal end the hami carry a tripartite, barbed grappling hook (60 nm in diameter). The architecture of this molecular hook is reminiscent of man‐made fishhooks, grapples and anchors. It appears that nature has developed a perfect mechanical nano‐tool in the course of biological evolution, which also might prove useful in the field of nanobiotechnology.
Co‐regulation of Salmonella enterica genes required for virulence and resistance to antimicrobial peptides by SlyA and PhoP/PhoQ
Authors: Navarre William Wiley , Halsey Thomas A. , Walthers Don , Frye Jonathan , McClelland Michael , Potter Jennifer L. , Kenney Linda J. , Gunn John S. , Fang Ferric C. , Libby Stephen J.
Published: March 2005

Analysis of the transcriptome of slyA mutant Salmonella enterica serovar Typhimurium revealed that many SlyA‐dependent genes, including pagC, pagD, ugtL, mig‐14, virK, phoN, pgtE, pipB2, sopD2, pagJ and pagK, are also controlled by the PhoP/PhoQ regulatory system. Many SlyA‐ and PhoP/PhoQ‐co‐regulated genes have functions associated with the bacterial envelope, and some have been directly implicated in virulence and resistance to antimicrobial peptides. Purified His‐tagged SlyA binds to the pagC and mig‐14 promoters in regions homologous to a previously proposed ‘SlyA‐box’. The pagC promoter lacks a consensus PhoP binding site and does not bind PhoP in vitro, suggesting that the effect of PhoP on pagC transcription is indirect. Stimulation of pagC expression by PhoP requires SlyA. Levels of SlyA protein and mRNA are not significantly changed under low‐magnesium PhoP‐inducing conditions in which pagC expression is profoundly elevated, however, indicating that the PhoP/PhoQ system does not activate pagC expression by altering SlyA protein concentration. Models are proposed in which PhoP may control SlyA activity via a soluble ligand or SlyA may function as an anti‐repressor to allow PhoP activation. The absence of almost all SlyA‐activated genes from the Escherichia coli K12 genome suggests that the functional linkage between the SlyA and PhoP/PhoQ regulatory systems arose as Salmonella evolved its distinctive pathogenic lifestyle.
Synthesis and evaluation of a new series of peptide‐based endothelin receptor antagonists
Authors: Dong J. , Han H. , Geng B. , Li X. , Gong Z. , Liu K.
Published: March 2005

Abstract:  Novel peptide‐based endothelin (ET) receptor antagonists were designed and synthesized in our laboratory. BQ‐485, HIM‐CO‐Leu‐d‐Trp‐d‐Trp‐OH, was selected as the leading compound. The primary structures of these new tripeptides were ABO‐CO‐Leu‐d‐Trp‐d‐AA(X)‐OH. The introduction of unnatural aromatic amino acids into these tripeptides was useful in the structure–activity relationship studies. Among the 20 tripeptides, 16 of them showed high activities against the contraction of rat aortic smooth muscles induced by ET‐1.
Binding of endomorphin‐2 to μ‐opioid receptors in experimental mouse mammary adenocarcinoma
Authors: Fichna J. , Do‐Rego J.‐C. , Mirowski M. , Costentin J. , Janecka A.
Published: March 2005

Abstract:  Endomorphin‐2 (Tyr‐Pro‐Phe‐Phe‐NH2) binds with high affinity and selectivity to the μ‐opioid receptor. In the present study, [125I]endomorphin‐2 has been used to characterize μ‐opioid‐binding sites on transplantable mouse mammary adenocarcinoma cells. Cold saturation experiments performed with [125I]endomorphin‐2 (1 nm) show biphasic binding curves in Scatchard coordinates. One component represents high affinity and low capacity (Kd = 18.79 ± 1.13 nm, Bmax = 635 ± 24 fmol/mg protein) and the other shows low affinity and higher capacity (Kd = 7.67 ± 0.81 μm, Bmax = 157 ± 13 pmol/mg protein) binding sites. The rank order of agonists competing for the [125I]endomorphin‐2 binding site was [d‐1‐Nal3]morphiceptin > endomorphin‐2 ≫ [d‐Phe3]morphiceptin > morphiceptin > [d‐1‐Nal3]endomorphin‐2, indicating binding of these peptides to μ‐opioid receptors. The uptake of 131I‐labeled peptides administered intraperitoneally to tumor‐bearing mice was also investigated. The highest accumulation in the tumor was observed for [d‐1‐Nal3]morphiceptin, which reached the value of 8.19 ± 1.14% dose/g tissue.
Influence of Water Stress on the Chemical Composition of Seeds of Two Lupins (Lupinus albus and Lupinus mutabilis)
Authors: Carvalho I. S. , Chaves M. , Pinto Ricardo C.
Published: March 2005

We have performed chemical proximate analysis and determined the carbohydrate profile of mature seeds of Lupinus albus, cv. Rio Maior and Lupinus mutabilis, cv. Potosi plants, either well watered (ww) or subjected to a water‐stress period (imposed from the 15th to 35th day after anthesis). Protein content from lupin seeds was 450 and 320 g kg−1 of seed on dry weight basis, for ww plants, respectively, of L. albus and L. mutabilis. Water stress did not affect protein content. The oil content of ww plants was about 120 g kg−1 of seed dry weight for L. albus and 180 g kg−1 of seed dry weight for L. mutabilis. Water stress reduced those values of half. The sugar content was about 90 g kg−1 for L. albus and 50 g kg−1 of seed dry weight for L. mutabilis, in ww plants. Water stress led to an increase in sugar content to 200 and 130 g kg−1 of seed dry weight, respectively, for L. albus and L. mutabilis. The α‐galactosides amounted to 70 % of the total sugars (raffinose being 30 % and stachyose, 40 %) and sucrose was about 20 % of the total sugars. Water stress increased total carbohydrates and increased the sucrose/α‐galactoside ratio, although reducing raffinose content and increasing sucrose content.
Seed Priming Increases Crop Yield Possibly by Modulating Enzymes of Sucrose Metabolism in Chickpea
Authors: Kaur S. , Gupta A. K. , Kaur N.
Published: March 2005

The number of seeds and seed yield per plant were higher in chickpea crops raised from water and mannitol (4 %) primed seeds in comparison with the control non‐primed crops. In primed plants, an enhanced acid invertase activity in the apical part of the main stem and the part immediately below it at 100 and 130 days after sowing (DAS) might result in an increased availability of hexoses to these plant parts. In addition, decreased acid invertase activity at the point of initiation of branches and in the internodes of stem observed in primed plants indicated restricted hydrolysis of sucrose during its transport through the stem, resulting in its more supply to the actively growing sinks. The activities of sucrose‐cleaving enzymes, i.e. invertase and sucrose synthase (SS) in podwall of primed plants were higher at 110 DAS. At 140 DAS, a stage of rapid seed filling, increased activities of SS and sucrose phosphate synthase (SPS) were observed in seeds of primed plants. Increased SPS activity in seeds of primed crop could meet the increased assimilate requirements of the developing seeds. Higher activity of SS in seeds of primed crop may facilitate seed filling. These data suggest that enzymes of sucrose metabolism play an important role in increasing the yield of chickpea crops raised from primed seeds.
Alternate Row Spacing and Plant Density Effects on Forage and Dry Matter Yield of Corn Hybrids (Zea mays L.)
Authors: Turgut I. , Duman A. , Bilgili U. , Acikgoz E.
Published: March 2005

Irrigated field experiments were conducted in the Marmara region of Turkey in 2002 and 2003 to compare alternate 40 : 25 cm row spacings and conventional 65 cm with four different plant densities (65 000, 85 000, 105 000 and 125 000 plants ha−1) of three corn hybrids (DK‐585, ADA 95–10 and C‐955) in some morphological traits and forage and dry matter yield. Morphological traits such as plant height, leaf per plant, stem diameter, ear per plant and ear percentage were measured, forage and dry matter yield was also determined in this study. Hybrids, row spacings and plant densities significantly affected some morphological traits, forage and dry matter yield at 0.01 level. Later maturing hybrids tended to produce taller and thicker stemmed plants. Row spacings and plant densities did not affect plant height. Average stem diameter increased significantly with population density. Row spacings did not influence leaf number, whereas leaf number increased slightly with plant density. On average, all corn plants had slightly more than 1.0 ear per plant in our experiment. Row spacings and plant densities did not affect significantly number of ear per plant. Early maturing DK‐585 had the highest ear percentage whilst late maturing C‐955 lowest. Yields usually increased with hybrid maturity. When averaged across years, row spacings and plant densities, late maturing C‐955 performed significantly better in forage and dry matter yield in all experimental years and combined years. The studies showed favourable advantage for alternate 40 : 25 cm rows over conventional 65 cm row spacings at all plant densities. Average forage and dry matter yields were greater for alternate 40 : 25 cm row spacings than for 65 cm row spacings. However, strong hybrid × row spacing interactions for both forage and dry matter yield were detected.
Neural basis of fear conditioning induced by video clip: Positron emission tomography study
Authors: DORONBEKOV TALANT K. , TOKUNAGA HIROMASA , IKEJIRI YOSHITAKA , KAZUI HIROAKI , HATTA NAOKI , MASAKI YOSHIHIRO , OGINO ATSUSHI , MIYOSHI NORIKO , OKU NAOHIKO , NISHIKAWA TAKASHI , TAKEDA MASATOSHI
Published: March 2005

Abstract  In patients with post‐traumatic stress disorder (PTSD), re‐experiencing the trauma is often induced by external cues in the environment. The cues, which were emotionally neutral for the patients before the traumatic event, become fearful ones after the event. This phenomenon is considered to be associated with fear conditioning. The paradigm was set up so that the emotionality changes in the patients with PTSD would be reproduced, and the regional cerebral blood flow (rCBF) measured with positron emission tomography (PET) was compared during exposure to the same stimuli before and after acquisition of fear conditioning. Ten healthy male subjects were asked to look at some emotionally neutral photos, then to watch a video with fearful content that also contained images similar to that presented in the photos, and afterwards to look at the photos again. Five of the 10 subjects felt that the object in the photos was more fearful after watching the video than before, and they were considered to have acquired fear conditioning. In those five subjects, the rCBF in the right amygdala and the left posterior cingulate gyrus after acquisition of fear conditioning significantly increased relative to the rCBF before conditioning. Thus, these regions seem to have a critical role in fear conditioning.
Quality of life of schizophrenic patients living in the community: The relationships with personal characteristics, objective indicators and self‐esteem
Authors: KUNIKATA HIROKO , MINO YOSHIO , NAKAJIMA KAZUO
Published: March 2005

Abstract  The relationship of personal characteristics, objective indicators, and self‐esteem to quality of life (QOL) was investigated cross‐sectionally in 73 Japanese schizophrenic patients, and the question of how objective conditions affect subjective evaluation was evaluated. Depressive mood and uncooperativeness were negatively correlated with self‐esteem, and self‐esteem was positively correlated with QOL. Self‐esteem was considered to directly affect QOL, and depressive mood and uncooperativeness to affect QOL via self‐esteem. Findings suggest that, in order to improve the QOL of schizophrenia patients, interventions to help alleviate psychiatric symptoms (e.g. depressive mood, uncooperativeness) must be utilized. A change in Japanese society itself must occur so that the consequences of stigma may be reduced and patient coping skills improved.
Effect of removing a dominant competitor, Akodon azarae (Rodentia, Sigmodontinae) on community and population parameters of small rodent species in Central Argentina
Authors: BUSCH MARÍA , BILENCA DAVID N. , CITTADINO EMILIO A. , CUETO G. R.
Published: March 2005

Abstract  We studied the effect of removing Akodon azarae (Muridae, Sigmodontinae) on community and demographic parameters of rodent species in crop field borders of Central Argentina. We applied three replicated treatments: enclosure and removal of A. azarae, enclosure without removal, and a control without removal or enclosure. We conducted 14 monthly capture–mark–recapture samplings between October 1988 and March 1990. During the study period we observed an increase in Mus domesticus (Muridae, Murinae) abundance in removal areas. Other species did not respond to A. azarae removal. When A. azarae was removed, M. domesticus appeared to be competitively dominant over the remaining species of the community, increasing its relative abundance. Reproductive parameters of M. domesticus were more sensitive to treatments than survival parameters.
Distributions of lizard species across edges delimiting open‐forest and sand‐mined areas
Authors: BRAGG JASON G. , TAYLOR JENNIFER E. , FOX BARRY J.
Published: March 2005

Abstract  The distributions of lizards across habitat edges delimiting open‐forest and regenerating sand‐mined areas as a function of distance from the edge were studied at Tomago, New South Wales, Australia. Pitfall‐trapping was used to survey lizards across the northern edges of four forest fragments, to determine if lizards displayed characteristic responses across the edge, and whether these could be explained by the different habitat conditions. At each site, 11 equally spaced drift fences (each parallel to the edge) were arranged in a transect running perpendicular to the edge, and stretching 50 m into each habitat type. Captures of Amphibolurus muricatus (Agamidae) decreased substantially across the edge from the mine‐path to the forest so that it was identified as a mine‐path specialist lizard species. Captures of two skink species decreased across the mine‐path before reaching the edge, and were not caught (Ctenotus taeniolatus) or were seldom caught (Ctenotus robustus) in the forest, so they were identified as mine‐path specialist, edge avoiding, lizard species. Captures of Lampropholis delicata (Scincidae) increased across edges into the forest, consistent with the expectation for a forest specialist. Regression analyses indicated the responses to edges of three lizard species (A. muricatus, C. robustus and C. taeniolatus) were negatively correlated with canopy cover (probably due to its influence on temperature, as captures of A. muricatus and C. robustus were also correlated positively with mean daily temperature). In addition, the response of C. robustus correlated negatively with a vegetation factor (dense, even vegetation in the first 50 cm from ground level). The response of L. delicata correlated positively with understorey height. We have identified edge response strategies for four species of lizards across edges delimiting temperate open‐forest and mined areas, and identified habitat and microclimate variables that may have driven these responses.
Epiphytic ferns and bryophytes of Tasmanian tree‐ferns: A comparison of diversity and composition between two host species
Authors: ROBERTS NINA R. , DALTON PATRICK J. , JORDAN GREGORY J.
Published: March 2005

Abstract  Ferns, bryophytes and lichens are the most diverse groups of plants in wet forests in south‐eastern Australia. However, management of this diversity is limited by a lack of ecological knowledge of these groups and the difficulty in identifying species for non‐experts. These problems may be alleviated by the identification and characterization of suitable proxies for this diversity. Epiphytic substrates are potential proxies. To evaluate the significance of some epiphytic substrates, fern and bryophyte assemblages on a common tree‐fern species, Dicksonia antarctica (soft tree‐fern), were compared with those on a rare species, Cyathea cunninghamii (slender tree‐fern), in eastern Tasmania, Australia. A total of 97 fern and bryophyte species were recorded on D. antarctica from 120 trunks at 10 sites, and 64 species on C. cunninghamii from 39 trunks at four of these sites. The trunks of C. cunninghamii generally supported fewer species than D. antarctica, but two mosses (particularly Hymenodon pilifer) and one liverwort showed significant associations with this host. Several other bryophytes and epiphytic ferns showed an affinity for the trunks of D. antarctica. Species assemblages differed significantly between both sites and hosts, and the differences between hosts varied significantly among sites. The exceptionally high epiphytic diversity associated with D. antarctica suggests that it plays an important ecological role in Tasmanian forests. Evidently C. cunninghamii also supports a diverse suite of epiphytes, including at least one specialist species.
Fire frequency and biodiversity conservation in Australian tropical savannas: implications from the Kapalga fire experiment
Authors: ANDERSEN ALAN N. , COOK GARRY D. , CORBETT LAURIE K. , DOUGLAS MICHAEL M. , EAGER ROBERT W. , RUSSELL‐SMITH JEREMY , SETTERFIELD SAMANTHA A. , WILLIAMS RICHARD J. , WOINARSKI JOHN C. Z.
Published: March 2005

Abstract  Every year large proportions of northern Australia's tropical savanna landscapes are burnt, resulting in high fire frequencies and short intervals between fires. The dominant fire management paradigm in these regions is the use of low‐intensity prescribed fire early in the dry season, to reduce the incidence of higher‐intensity, more extensive wildfire later in the year. This use of frequent prescribed fire to mitigate against high‐intensity wildfire has parallels with fire management in temperate forests of southern Australia. However, unlike in southern Australia, the ecological implications of high fire frequency have received little attention in the north. CSIRO and collaborators recently completed a landscape‐scale fire experiment at Kapalga in Kakadu National Park, Northern Territory, Australia, and here we provide a synthesis of the effects of experimental fire regimes on biodiversity, with particular consideration of fire frequency and, more specifically, time‐since‐fire. Two recurring themes emerged from Kapalga. First, much of the savanna biota is remarkably resilient to fire, even of high intensity. Over the 5‐year experimental period, the abundance of most invertebrate groups remained unaffected by fire treatment, as did the abundance of most vertebrate species, and we were unable to detect any effect of fire on floristic composition of the grass‐layer. Riparian vegetation and associated stream biota, as well as small mammals, were notable exceptions to this general resilience. Second, the occurrence of fire, independent of its intensity, was often the major factor influencing fire‐sensitive species. This was especially the case for extinction‐prone small mammals, which have suffered serious population declines across northern Australia in recent decades. Results from Kapalga indicate that key components of the savanna biota of northern Australia favour habitat that has remained unburnt for at least several years. This raises a serious conservation concern, given that very little relatively long unburnt habitat currently occurs in conservation reserves, with most sites being burnt at least once every 2 years. We propose a conservation objective of increasing the area that remains relatively long unburnt. This could be achieved either by reducing the proportion of the landscape burnt each year, or by setting prescribed fires more strategically. The provision of appropriately long unburnt habitat is a conservation challenge for Australia's tropical savanna landscapes, just as it is for its temperate forests.
Host associations of the strangler fig Ficus watkinsiana in a subtropical Queensland rain forest
Authors: MALE TIMOTHY DAVID , ROBERTS GUINNEVERE ELLEN
Published: March 2005

Abstract  The distribution of epiphytic organisms is limited by the availability of, and dispersal to suitable hosts. We examined the distribution of a hemi‐epiphytic strangler fig, Ficus watkinsiana (Moraceae) in Cooloola National Park (Queensland, Australia), in order to determine whether this species exhibits a preference for certain host species and why. We assessed host bark roughness and flakiness, fruit type, and size to explain the observed distribution of F. watkinsiana. We surveyed over 1900 potential host trees of the 30 most common forest canopy species and found that host size measured by diameter at breast height accounted for most variation in fig prevalence (Binary Logistic Regression log‐likelihood = −588.178, G = 314.494, d.f. = 1, P < 0.005). After controlling for host size, F. watkinsiana prevalence still differed significantly between host species (χ2 = 54.612, d.f. = 24, P < 0.005), a difference that was only partly explained by variation in the bark roughness of host trunks. These results suggest that variation in the rate at which tree species host strangler figs are primarily related to individual tree size – figs may simply be more likely to colonize and thrive upon host species that grow larger.