bluuebunny/crossref_metadata_2025 huggingface dataset:
Pharmacokinetic profile of lanreotide Autogel® in patients with acromegaly after four deep subcutaneous injections of 60, 90 or 120 mg every 28 days
Authors: Bronstein M. , Musolino N. , Jallad R. , Cendros J. M. , Ramis J. , Obach R. , Leselbaum A. , Catus F.
Published: October 2005

Objective  To investigate the pharmacokinetic profile of a prolonged release, aqueous Autogel® formulation of the somatostatin analogue lanreotide (Lan‐ATG).

Design  A phase II, randomized, double‐blind study, during which patients received 60, 90 or 120 mg Lan‐ATG for four fixed administrations at 28‐day intervals.

Patients  A total of 18 patients with acromegaly were recruited; six patients were randomized to each treatment.

Measurements  Lanreotide minimum concentration (Cmin), maximum serum concentration (Cmax) and area under the concentration–time curve during a dosing interval (AUCτ) were assessed after a single dose and at steady state (ss). Serum GH and IGF‐1 levels were assessed before each administration and at the end of the study.

Results  After a single administration, dose proportionality for Cmin,1, Cmax and AUCτ was demonstrated statistically. After repeated administrations, Lan‐ATG exhibited linear pharmacokinetics over the dose range and ss values of Cmin, Cmax and AUCτ increased in a dose‐dependent, linear manner. Mean Cmax,ss values were only two‐ to fourfold greater than Cmin,ss values, and there was good control over the entire release profile. Serum levels of GH and IGF‐1 declined over the course of the study and acromegaly symptoms improved. The treatment was well tolerated.

Conclusions  Lan‐ATG showed linear pharmacokinetic profiles over the three dose levels after both single and repeated dosing, no initial burst effect and good control over the entire release profile. Despite the absence of dose adaptation, four injections of Lan‐ATG were effective in lowering serum levels of GH and IGF‐1.
Investigating a trade‐off in root morphological responses to a heterogeneous nutrient supply and to flooding
Authors: JANSEN C. , VAN DE STEEG H. M. , DE KROON H.
Published: October 2005

Flood‐sensitive plant species are restricted to highly elevated sites in floodplains, but why flood‐tolerant plants do not grow at higher elevations is much less clear. We test the hypothesis that a trade‐off exists between flood‐tolerance and selective root placement in nutrient‐rich patches, a putatively important trait in the more competitive highly elevated sites.

Achillea ptarmica, Achillea millefolium, Rumex palustris, Rumex thyrsiflorus, Ranunculus repens, Ranunculus bulbosus, Festuca arundinacea and Festuca rubra were subjected to a drained, waterlogged or partially submerged treatment to test their flood‐tolerance. Within each species pair, the former are more tolerant to flooding while the latter are relatively flood‐sensitive. In another experiment, plants were grown in soil with either a homogeneous or a heterogeneous nutrient distribution. All species placed their roots selectively in the enriched patch, but overall the flood‐tolerant species were less selective than the flood‐sensitive ones. The wetland species R. palustris was an exception, with very high root plasticity in response to both flooding and nutrient heterogeneity.

The negative correlation between selective root placement and flood‐tolerance for seven out of eight species suggests that each of these traits has been selected for in its own environment. The exception of R. palustris indicates that there are no physiological or genetic trade‐offs involved in explaining this correlation. Species from more frequently flooded habitats were less able to respond morphologically to nutrient‐rich patches in the soil, and are therefore more likely to be outcompeted at the more highly elevated sites. Rumex palustris may use its ability to place roots selectively in nutrient‐enriched patches to benefit from the nutrients released during drained periods in its dynamic habitat.
Condition, reproduction and survival of barn swallows from Chernobyl
Authors: MØLLER A. P. , MOUSSEAU T. A. , MILINEVSKY G. , PEKLO A. , PYSANETS E. , SZÉP T.
Published: October 2005

We investigated the relationship between radiation arising from the fall‐out due to the explosion of the nuclear reactor at Chernobyl, Ukraine, and body condition, rate of reproduction and survival in a migratory passerine bird, the barn swallowHirundo rusticaL., by comparing a contaminated region and a control region (Kanev) during 6 years between 1991 and 2004.

The fraction of nonreproducing adults was on average 23% in Chernobyl compared with close to zero in Kanev and other European populations.

Body condition as estimated from body mass was similar in Chernobyl and Kanev. Although laying date did not differ significantly between the two regions, clutch was reduced by 7%, brood size by 14% and hatching success by 5% in the Chernobyl region relative to the control area.

Annual adult survival, estimated from mark–recapture analyses, was on average 28% in the Chernobyl region, but 40% in Kanev.

The relationships were generally confirmed in rank correlation analyses between response variables and ambient radiation levels in different colonies.

The overall findings are consistent with the hypothesis that radioactive contamination in the Chernobyl region has significant negative impact on rates of reproduction and survival of the barn swallow. We hypothesize that these effects are mediated by antioxidants and/or mutations.
Interspecific variation in antipredator behaviour leads to differential vulnerability of mule deer and white‐tailed deer fawns early in life
Authors: LINGLE SUSAN , PELLIS SERGIO M. , WILSON W. FINBARR
Published: October 2005

Ungulates are viewed as being highly susceptible to predation during the initial weeks or months of life. Yet aggressive defence by adult females is common in many ungulates and has the potential to reduce the vulnerability of the young significantly.

We observed naturally occurring predatory encounters between coyotesCanis latransSay and deer fawns to test the hypothesis that a difference in aggressive defence leads to the differential vulnerability of mule deerOdocoileus hemionusRafinesque and white‐tailed deerO. virginianusZimmermann fawns in summer, when fawns are 0–14 weeks in age. Whitetail fawns suffer higher levels of coyote predation than do mule deer fawns at that time. The two species of deer are similar in size, but are known to differ in their antipredator behaviour in winter when fawns are older.

Coyotes were less likely to attack mule deer than whitetail fawns they encountered, and were less likely to kill mule deer than whitetail fawns they attacked.

The presence of a mule deer, but not a whitetail, female with a fawn deterred coyotes from attacking the fawn. Once attacked, fawns of both species were less likely to be killed when females defended them, but mule deer females were far more likely to defend fawns.

Mule deer females defended fawns that were not their own offspring, including heterospecific fawns. Mule deer fawns were more likely to be defended if they had a larger number of females nearby when encountered. These observations raise the possibility that mule deer, and even whitetail, fawns may have improved survival in areas with higher densities of mule deer females.

These results show that higher levels of defence by mule deer females reduced the vulnerability of mule deer fawns, contributing to the lower predation rates reported for mule deer than for whitetail fawns of this age group.
Multiple predator effects in an intertidal food web
Authors: VAN SON THIJS CHRISTIAAN , THIEL MARTIN
Published: October 2005

We examined the effects of multiple predators from an intertidal boulder food web to test whether and how three different predator species affected the survival of a small amphipod species.

Predators were chosen because they differ in their foraging mode, two feeding at the bottom and in benthic refuges (nemertean and shrimp) and one in the water‐column (juveniles of a fish).

Mortality of amphipods was not affected by nemerteans, but was high in the presence of shrimp or fish. Highest mortalities were observed in predator‐combinations that contained both shrimp and fish. Amphipods responded to shrimp by escaping into the water column, while they avoided fish by remaining in the refuge. We conclude that predator‐specific defence causes conflicts for prey when both shrimp and fish are present.

Comparing observed effects of multiple predators with expected effects revealed risk enhancement for the shrimp + fish combination. A comparison of different predictive models revealed that the multiplicative model was most appropriate, although additive models may work well under certain conditions.

Based on known consumption‐ranges of the predators used, we conclude that nemerteans were saturated with prey while fish were far from their saturation point. A predator's functional response curve (prey consumption in relation to prey abundance) determines its impact on prey populations. This knowledge appears essential in order to predict whether prey organisms face risk enhancement, risk reduction or additive effects of multiple predators.
Older patients’ experience of dressing changes on venous leg ulcers: more than just a docile patient
Authors: Ebbeskog Britt , Emami Azita
Published: October 2005

Aim and objective.  The aim of this paper was to describe the lived experiences of older patients with venous leg ulcers, during dressing changes as out patients with a focus of their concerns about care interventions. Research on wound care management has focused on treatment of venous leg ulcer, wound assessments and the choice of dressing material. Few studies have focused on the patients’ experience of dressing changes.

Design.  Fifteen older people with verified venous leg ulcers were recruited in a metropolitan area of Sweden. Data were collected with research interviews in the form of dialogue.

Method.  Data were analysed with an interpretative phenomenological method developed by Benner.

Results.  Twelve women and three men participated. The themes were: ‘being cared for with a skilful touch’, ‘feelings of belonging, continuity and affinity’, and ‘being suppressed into a state where one loses control, leading to feelings of discomfort’. The participants’ experiences varied. Some were satisfied and felt that there was a mutual understanding between caregivers and patients, while others were dissatisfied and felt objectified. Understanding the patients as human beings and considering illness as lived experience helped the care providers to perform skilful wound care, in an atmosphere of mutual understanding.

Conclusion.  The patients suffering from venous leg ulcers wanted to feel worthy of wound treatment and to meet skilful, confident and gentle nurses in a sharing atmosphere. Nurses must be perceptive to the individual's bodily experience of the leg ulcer.

Relevance to clinical practice.  Wound care requires a multidimensional clinical approach that involves not only medical and technical care strategies of dressings and bandages, but also aspects that concern the situated‐based illness experience that persons suffering from leg ulcers may face.
Health Needs Instrument for hospitalized single‐living Taiwanese elders with heart disease: triangulation research design
Authors: Shih Shaw‐Nin , Gau Meei‐Ling , Kao Lo Chi‐Hui , Shih Fu‐Jin
Published: October 2005

Aim.  The aims of this study were (a) to explore the health needs of hospitalized Taiwanese older people with heart disease who live alone in the community; (b) to develop an instrument to assess their health needs and (c) to examine relationships among their health needs.

Design.  Three phases were involved in this between‐method triangulation design.

Methods.  The first phase explored the contextual content of the health needs from the perspectives of a purposive sampling of 34 subjects by the use of an explorative qualitative method. The second phase developed the Health Needs Instrument (HNI) and established its reliability and validity. The last phase implemented the instrument in a cohort and examined their appraisals of each type of health need as well as the relationships among different types of health needs.

Results.  The HNI encompasses the following five types of health needs: help in managing tangible things, psychological support, medical support, obtaining health information and participation in decision‐making. In the last phase, a purposive sample of 54 subjects (48 men and 6 women) with an average age of 75·3 years was obtained. Subjects’ health needs were ranked as obtaining health information (100%), participation in decision‐making (96%), managing tangible issues (87%), medical support (86%) and psychological support (67%). Detailed items for each type of health need were revealed. By examining the relationship between their health needs, the psychological needs in confronting the subjects’ physical discomfort had a significant correlation with medical support (r = 0·469, P < 0·01), with tangible needs after surgery or an invasive examination (r = 0·460, P < 0·01), with informational needs (r = 0·393, P = 0·034) and with tangible needs of maintaining daily living activities during the hospitalization period (r = 0·290, P = 0·034). The need for tangible help in maintaining daily living activities during the hospitalization period was significantly correlated with the need for medical support (r = 0·341, P = 0·012), with help in managing admissions and discharge procedures (r = 0·374, P = 0·05) and with help after an invasive examination or in the postsurgery period (r = 0·334, P = 0·013).

Conclusion.  Finally, a conceptual framework was developed to depict this phenomenon. With the help of this HNI, both Eastern and Western health care providers can be empowered to detect the complex health needs of this particular population earlier and more accurately in order to promote their well‐being as well as their health‐related quality of life.

Relevance to clinical practice.  Empowering nurse clinicians to assess health needs of hospitalized single‐living Taiwanese elders with heart disease.
Effects of a feeding skills training programme on nursing assistants and dementia patients
Authors: Chang Chia‐Chi , Lin Li‐Chan
Published: October 2005

Aims and objectives.  The purposes of this study were to develop a comprehensive feeding skills training programme for nursing assistants and to test the effects of this training programme on their knowledge, attitude and behaviour and the outcome of dementia patients including total eating time, food intake and feeding difficulty.

Background.  Dementia patients have a high probability of feeding problems that result in a substantial risk of malnutrition. Assisting residents with eating is a major task for nursing assistants and they require better training to provide adequate quality of nutritional care.

Design methods.  A quasi‐experimental study was conducted. Two convenience‐chosen dementia‐specialized long‐term care facilities in North Taiwan were randomly assigned into either a control or a treatment group. Sixty‐seven nursing assistants were enrolled (treatment: 31; control: 36). Twenty nursing assistants and the same number of dementia patients were observed during mealtime. The treatment group participated in a feeding skills training programme including three hours of in‐service classes and one hour of hands‐on training, whereas the control group did not receive any training.

Results.  The treatment group had significantly more knowledge (F = 47·7, P < 0·001), more positive attitude (F = 15·75, P = 0·001) and better behaviours (t = 6·0, P < 0·001) than the control group after the intervention. Dementia patients in the treatment group had significantly longer total eating time (t = 2·7, P < 0·05) and higher Edinburgh Feeding Evaluation in Dementia scores (more feeding difficulty) (t = 2·1, P < 0·05) than the control group. There was no significant difference on food intake between the two groups (t = 0·8, P = 0·49).

Conclusion.  This feeding skills training programme has been found to change nursing assistants’ knowledge, attitude, and behaviour as well as increasing the eating time for the dementia patients.

Relevance to clinical practice.  This study raises attention regarding on‐the‐job training for nursing assistants. Furthermore, the feeding problems among dementia patients should be further explored as well as the nutritional care.
Transference, counter‐transference and repetition: some implications for nursing practice
Authors: Jones Alun C
Published: October 2005

Aims.  This discussion paper offers an introductory text for nurses and explores the psychoanalytic ideas of transference, counter‐transference and repetition compulsion. Disguised case vignettes provide illustrations of the ideas as they might apply to nursing, including professional practice and occupational choice.

Background.  The literature suggests that transference can be a source of creativity as well as destructiveness and influence important communications with oneself and others including the choice of nursing and other health professions as an occupation. Recognizing possibilities of transference, counter‐transference along with repetitive patterns of behaviours, can help nurses of all specialities to address situations constructively by responding thoughtfully and appropriately.

Conclusion.  This discussion concludes with the suggestions that we know little about the motivational factors underlying nursing as an occupational preference; moreover, nursing does not have a culture of personal therapy. As such nurses are denied opportunities to understand the possible reasons underlying their occupational choice or gain experiential knowledge of interpersonal dynamics occurring between patients and colleagues.

Relevance to clinical practice.  Transference and counter‐transference are thought to have some bearing on all relationships. Forming a natural part of the way human beings relate to each other, transference and counter‐transference can bring about sincere human interest, caring and concern. However, there is also potential for disagreements. Recognizing the possible origins of relational difficulties can offer opportunities for professional development to nurses along with the benefits for health service users.
Influence of prolonged dalteparin treatment on coagulation, fibrinolysis and inflammation in unstable coronary artery disease
Authors: OLDGREN J. , FELLENIUS C. , BOMAN K. , JANSSON J.‐H. , NILSSON T. K. , WALLENTIN L. , SIEGBAHN A.
Published: October 2005

Background.  Unstable coronary artery disease (CAD) is a multi‐factorial disease involving thrombotic and inflammatory processes. Short‐term low molecular weight (LMW) heparin treatment reduces coagulation activity and clinical events. We investigated the influence of prolonged treatment on coagulation, fibrinolysis and inflammation.

Methods and results.  Serial blood samples were obtained from 555 of 2267 unstable CAD patients in the FRISC II study. Patients were treated with the LMW heparin dalteparin 120 IU kg−1 s.c. twice daily for 5–7 days and randomized to placebo (n = 285) or gender and weight‐adjusted doses of dalteparin (5000 or 7500 IU) twice daily (n = 270) for 3 months. Dalteparin persistently depressed coagulation activity with, when compared with placebo, lower median levels of factor VIIa (63 IU mL−1 vs. 84 IU mL−1), prothrombin fragment 1 + 2 (0.86 nmol L−1 vs. 1.09 nmol L−1) and D‐dimer (21 μg L−1 vs. 43 μg L−1) after 3 months, all P < 0.01. Reactivation of coagulation activity was observed after cessation of both short‐term and prolonged dalteparin treatment. Higher levels of tPA/PAI‐1 complex (11.7 μg L−1 vs. 6.5 μg L−1, P < 0.001) and von Willebrand factor (162% vs. 136%, P < 0.001) were found during prolonged dalteparin treatment. Interleukin‐6, C‐reactive protein and fibrinogen levels were unaffected by dalteparin treatment.

Conclusions.  Three months dalteparin treatment resulted in a sustained and pronounced reduction of coagulation activity, which corresponds to the observed reduction in death and myocardial infarction during the initial 6 weeks in the FRISC II study. The persistently elevated levels of tPA/PAI‐1 complex and von Willebrand factor might reflect effects on platelets and endothelial cells and thus contribute to the gradually decreased efficacy by prolonged dalteparin treatment in unstable CAD.
Effect of Exercise on Ovarian Morphology and Expression of Nerve Growth Factor and α1‐ and β2‐Adrenergic Receptors in Rats with Steroid‐Induced Polycystic Ovaries
Authors: Manni L. , Cajander S. , Lundeberg T. , Naylor A. S. , Aloe L. , Holmäng A. , Jonsdottir I. H. , Stener‐Victorin E.
Published: October 2005

Oestadiol valerate (EV)‐induced polycystic ovaries (PCO) in rats cause anovulation and cystic ovarian morphology. Denervation of ovarian sympathetic nerves restores ovulatory disruption. In the present study, we determined whether 5 weeks of voluntary exercise influence ovarian morphology and the expression of sympathetic markers in the EV‐induced PCO rat model. The effect of exercise on (i) ovarian morphology; (ii) mRNA and protein expression of nerve growth factor (NGF); and (iii) mRNA and number of ovarian‐expressing cells for the NGF receptor (p75 neurotrophin receptor) and the α1a‐, α1b‐, α1d‐ and β2‐adrenergic receptors (ARs) in rats with EV‐induced PCO was evaluated. PCO was induced by a single i.m. injection of EV, and controls were injected with oil alone in adult cycling rats. The rats were divided into four groups: (i) control (oil); (ii) exercise group (oil + exercise); (iii) a PCO group (EV); and (iv) a PCO exercise group (EV + exercise). The exercise and PCO exercise groups ran voluntarily for 5 weeks in computer‐monitored wheels placed in the cages where they were housed. The results obtained indicated that ovarian morphology was almost normalised in the PCO exercise group; NGF mRNA and protein concentrations were normalised in the PCO exercise group; high numbers of NGF receptor expressing cells in PCO ovaries were lowered by exercise; and the number of immunopositive cells of the different AR subtypes were all reduced after exercise in the PCO group, except for the α1b‐ and β2‐AR whereas the mRNA levels were unaffected, indicating transcriptional regulation. In conclusion, our data indicate a beneficial effect of regular exercise, as a modulator of ovarian sympathetic innervation, in the prevention and treatment of human PCOS.
Hepatic expression of the proliferative marker Ki‐67 and p53 protein in HBV or HCV cirrhosis in relation to dysplastic liver cell changes and hepatocellular carcinoma
Authors: Koskinas J. , Petraki K. , Kavantzas N. , Rapti I. , Kountouras D. , Hadziyannis S.
Published: October 2005

Summary.  To evaluate hepatic expression of the nuclear proliferative marker Ki‐67 and the p53 oncoprotein in hepatitis B virus (HBV)/HCV cirrhosis in relation to dysplastic liver cell changes and hepatocellular carcinoma (HCC). We studied needle liver biopsies from 107 patients with cirrhosis and no HCC (52 HBV, 55 HCV) who had been assessed for protocol studies, and 57 cirrhotic patients with HCC (40 HBV, 17 HCV). We evaluated small and large cell dysplastic changes along with the expression of Ki‐67 and p53 by immunohistochemistry. The labelling index (LI) was defined as the proportion (%) of positive‐stained nuclei of the 500 measured. Large and small cell dysplastic changes were observed in 12 and 9% of specimens respectively. Only small cell changes were associated with Ki‐67 expression. Ki‐67 LI was 5.50 ± 5.7 in cirrhosis (13.90 ± 3.84 in those with small cell dysplastic changes vs 4.64 ± 4.98 in those without, P < 0.01), 10.2 ± 5.95 in cirrhosis with HCC (P < 0.05) and 18.56 ± 10 in HCC (P < 0.01). Neither the presence of small cell dysplastic changes nor the expression of Ki‐67 was related to severity or aetiology of cirrhosis. Expression of p53 was observed in 30% of the non‐tumorous and in 53% of the neoplastic tissue obtained from patients with HCC, with no differences between HCV and HBV. Ki‐67 and p53 expression was associated with the tumour grade (P < 0.001). Our observations clearly demonstrate the association between the proliferation activity and the morphological changes in the cirrhotic liver from the non‐dysplastic to dysplastic lesion to HCC. They also support the hypothesis that p53 alterations are a rather late event in carcinogenesis and related to HCC grade. And finally, they suggest that the final steps of hepatocarcinogenesis are common and independent of the aetiology of the chronic viral infection.
The −670A > G polymorphism in the promoter region of the FAS gene is associated with necrosis in periportal areas in patients with chronic hepatitis C
Authors: Aguilar‐Reina J. , Ruiz‐Ferrer M. , Pizarro Mª. A. , Antiñolo G.
Published: October 2005

Summary.  Evidence suggests that apoptosis of liver cells may play a significant role in the pathogenesis of hepatitis C virus (HCV) infection. One of the best characterized apoptotic pathway is that mediated by the death receptor Fas. Fas expression has been found to be up‐regulated on hepatocytes in chronic HCV infection, particularly in periportal areas. Recently, two polymorphisms have been identified in the promotor region of the FAS gene, −1377G > A and −670A > G. We have evaluated the involvement of these variants in the susceptibility to HCV infection, the severity of liver damage and progression of fibrosis in chronic hepatitis C. A cohort of 197 patients with chronic hepatitis C and 100 controls were analysed for both polymorphisms by Fluorescence Resonance Energy Transfer using specific probes and the LightcyclerTM system. In addition, liver biopsies were taken in 167 patients and scored using the Knodell classification system. We have found that the allele frequencies and the distribution of both polymorphisms do not differ significantly in the HCV cohort and in the control population. Thus, none of the polymorphisms seems to be related with susceptibility to HCV infection. However, we have examined the possible association between the two variants and the grade of necroinflammatory activity and the stage of fibrosis and we have detected an under‐representation of the −670A > G variant among those patients with higher Knodell's scores (P = 0.049) and necroinflammatory activity (P = 0.036). The −670A allele was associated with higher levels of periportal necrosis (P = 0.012). In conclusion, our findings suggest an association between the −670A > G polymorphism and the grade of necrosis in periportal areas in patients with chronic hepatitis C.
Multiple origin of metallicolous populations of the pseudometallophyte Arabidopsis halleri (Brassicaceae) in central Europe: the cpDNA testimony
Authors: PAUWELS MAXIME , SAUMITOU‐LAPRADE PIERRE , HOLL ANNE CATHERINE , PETIT DANIEL , BONNIN ISABELLE
Published: October 2005

The population structure of the pseudo‐metallophyte herb, Arabidopsis halleri, was studied using Polymerase Chain Reaction‐Restriction Fragment Length Polymorphism (PCR–RFLP) on chloroplast DNA (cpDNA). The history of metallicolous (M) populations showing increased zinc tolerance was investigated. Eight primer‐enzyme combinations out of 72 tested were applied to a total of 625 individuals from 28 widespread populations, 14 of them being M. Eleven distinct chlorotypes were found: five were common to nonmetallicolous (NM) and M populations, whereas six were only observed in one edaphic type (five in NM and one in M). No difference in chlorotype diversity between edaphic types was detected. Computed on the basis of chlorotype frequencies, the level of population differentiation was high but remained the same when taking into account levels of molecular divergence between chlorotypes. Isolation by distance was largely responsible for population differentiation. Geographically isolated groups of M populations were more genetically related to their closest NM populations than to each other. Our results suggest that M populations have been founded separately from distinct NM populations without suffering founding events and that the evolution towards increased tolerance observed in the distinct M population groups occurred independently.
Local forest environment largely affects below‐ground growth, clonal diversity and fine‐scale spatial genetic structure in the temperate deciduous forest herb Paris quadrifolia
Authors: JACQUEMYN HANS , BRYS REIN , HONNAY OLIVIER , HERMY MARTIN , ROLDÁN‐RUIZ ISABEL
Published: October 2005

Paris quadrifolia (herb Paris) is a long‐lived, clonal woodland herb that shows strong differences in local population size and shoot density along an environmental gradient of soil and light conditions. This environmentally based structuring may be mediated by differences in clonal growth and seedling recruitment through sexual reproduction. To study the interrelationship between environmental conditions and spatial patterns of clonal growth, the spatial genetic structure of four P. quadrifolia populations growing in strongly contrasting sites was determined. In the first place, plant excavations were performed in order to (i) determine differences in below‐ground growth of genets, (ii) investigate connectedness of ramets and (iii) determine total genet size. Although no differences in internode length were found among sites, clones in moist sites were much smaller (genets usually consisted of 1–3 interconnected shoots, most of them flowering) than genets in dry sites, which consisted of up to 15 interconnected shoots, the majority of which were vegetative. Further, amplified fragment length polymorphism (AFLP) markers were used. Clonal diversity was higher in populations located in moist and productive ash–poplar forests compared to those found in drier and less productive mixed forest sites (G/N: 0.27 and 0.14 and Simpson's D: 0.84 and 0.75, respectively). Patterns of spatial population genetic structure under dry conditions revealed several large clones dominating the entire population, whereas in moist sites many small genets were observed. Nevertheless, strong spatial genetic structure of the genet population was observed. Our results clearly demonstrate that patterns of clonal diversity and growth form of P. quadrifolia differ among environments. Limited seedling recruitment and large clone sizes due to higher connectedness of ramets explain the low clonal diversity in dry sites. In moist sites, higher levels of clonal diversity and small clone sizes indicate repeated seedling recruitment, whereas strong spatial genetic structure suggests limited seed dispersal within populations.
A genetic similarity rule determines arthropod community structure
Authors: BANGERT R. K. , TUREK R. J. , REHILL B. , WIMP G. M. , SCHWEITZER J. A. , ALLAN G. J. , BAILEY J. K. , MARTINSEN G. D. , KEIM P. , LINDROTH R. L. , WHITHAM T. G.
Published: October 2005

We define a genetic similarity rule that predicts how genetic variation in a dominant plant affects the structure of an arthropod community. This rule applies to hybridizing cottonwood species where plant genetic variation determines plant–animal interactions and structures a dependent community of leaf‐modifying arthropods. Because the associated arthropod community is expected to respond to important plant traits, we also tested whether plant chemical composition is one potential intermediate link between plant genes and arthropod community composition. Two lines of evidence support our genetic similarity rule. First, in a common garden experiment we found that trees with similar genetic compositions had similar chemical compositions and similar arthropod compositions. Second, in a wild population, we found a similar relationship between genetic similarity in cottonwoods and the dependent arthropod community. Field data demonstrate that the relationship between genes and arthropods was also significant when the hybrids were analysed alone, i.e. the pattern is not dependent upon the inclusion of both parental species. Because plant–animal interactions and natural hybridization are common to diverse plant taxa, we suggest that a genetic similarity rule is potentially applicable, and may be extended, to other systems and ecological processes. For example, plants with similar genetic compositions may exhibit similar litter decomposition rates. A corollary to this genetic similarity rule predicts that in systems with low plant genetic variability, the environment will be a stronger factor structuring the dependent community. Our findings argue that the genetic composition of a dominant plant can structure higher order ecological processes, thus placing community and ecosystem ecology within a genetic and evolutionary framework. A genetic similarity rule also has important conservation implications because the loss of genetic diversity in one species, especially dominant or keystone species that define many communities, may cascade to negatively affect the rest of the dependent community.
Hidden diversity and host specificity in cycliophorans: a phylogeographic analysis along the North Atlantic and Mediterranean Sea
Authors: OBST MATTHIAS , FUNCH PETER , GIRIBET GONZALO
Published: October 2005

In order to elucidate the evolutionary history and the population structure of the members of the phylum Cycliophora, which live commensally on three species of lobsters, we studied sequence variation in the mitochondrial gene cyctochromecoxidase subunit I. Overall 242 sequences from 16 locations on both coasts of the North Atlantic, including the North Sea and the Mediterranean, were analysed, revealing 28 haplotypes, with a maximum sequence divergence of 16.6%. Total genetic diversity was high (h = 0.8322, π = 0.0898), as it was for the commensals onHomarus americanus(17 haplotypes,h = 0.7506, π = 0.0504). However, it was low for commensals onNephrops norvegicus(6 haplotypes,h = 0.3899, π = 0.0035), and intermediate for cycliophorans onHomarus gammarus(5 haplotypes,h = 0.3020, π = 0.0140). Although two of the host lobsters co‐inhabit the coastal waters of Europe, a strong genetic structure (78.45% of the observed genetic variation) was detected among populations on all host species, indicating the existence of a reproductively isolated species on each lobster. In addition, genetic structure over long distances exists among populations on each host species. Such patterns can be explained by the limited dispersal ability of the cycliophoran chordoid larva. Demographic and phylogenetic analyses suggest old and possibly cryptic populations present onH. americanusandH. gammarus, while the latter may have experienced recent bottlenecks, perhaps during Pleistocene glaciations. Populations onN. norvegicusappear to be of recent origin.
Life history correlates of inbreeding depression in mandrills (Mandrillus sphinx)
Authors: CHARPENTIER M. , SETCHELL J. M. , PRUGNOLLE F. , WICKINGS E. J. , PEIGNOT P. , BALLOUX F. , HOSSAERT‐MCKEY M.
Published: October 2005

Inbreeding depression reflects the negative consequences of increased homozygosity at genes that affect fitness. We investigate inbreeding depression in a semi‐free‐ranging colony of mandrills (Mandrillus sphinx), using high‐quality pedigree data, comprising five maternal generations and 20 years of morphological and demographic data. We examine the relationship between inbreeding coefficients and four fitness correlates: two growth parameters (mass and height for age) and longevity in both sexes, and age at first conception in females. Inbreeding was correlated with both growth parameters, but only in females, with inbred females being smaller than noninbred females. Inbreeding was also correlated significantly with age at first conception, with inbred females giving birth earlier in life than noninbred females. We suggest that sex‐biased maternal investment may explain this sex‐differential response to inbreeding, although the lack of a significant association between inbreeding and growth in males may also be due to the provisioned nature of the colony. The surprising relationship between age at first conception and inbreeding may be related to smaller adult size in inbred females, or to their being less able to escape from male sexual coercion.
Conflicting patterns of mitochondrial and nuclear DNA diversity in Phylloscopus warblers
Authors: BENSCH STAFFAN , IRWIN DARREN E. , IRWIN JESSICA H. , KVIST LAURA , ÅKESSON SUSANNE
Published: October 2005

Molecular variation is often used to infer the demographic history of species, but sometimes the complexity of species history can make such inference difficult. The willow warbler, Phylloscopus trochilus, shows substantially less geographical variation than the chiffchaff, Phylloscopus collybita, both in morphology and in mitochondrial DNA (mtDNA) divergence. We therefore predicted that the willow warbler should harbour less nuclear DNA diversity than the chiffchaff. We analysed sequence data obtained from multiple samples of willow warblers and chiffchaffs for the mtDNA cytochrome b gene and four nuclear genes. We confirmed that the mtDNA diversity among willow warblers is low (π = 0.0021). Sequence data from three nuclear genes (CHD‐Z, AFLP‐WW1 and MC1R) not linked to the mitochondria demonstrated unexpectedly high nucleotide diversity (π values of 0.0172, 0.0141 and 0.0038) in the willow warbler, on average higher than the nucleotide diversity for the chiffchaff (π values of 0.0025, 0.0017 and 0.0139). In willow warblers, Tajima's D analyses showed that the mtDNA diversity, but not the nuclear DNA diversity, has been reduced relative to the neutral expectation of molecular evolution, suggesting the action of a selective sweep affecting the maternally inherited genes. The large nuclear diversity seen within willow warblers is not compatible with processes of neutral evolution occurring in a population with a constant population size, unless the long‐term effective population size has been very large (Ne > 106). We suggest that the contrasting patterns of genetic diversity in the willow warbler may reflect a more complex evolutionary history, possibly including historical demographic fluctuations or historical male‐biased introgression of nuclear genes from a differentiated population of Phylloscopus warblers.
Comparative population structure of Cynopterus fruit bats in peninsular Malaysia and southern Thailand
Authors: CAMPBELL POLLY , SCHNEIDER CHRISTOPHER J. , ADNAN ADURA M. , ZUBAID AKBAR , KUNZ THOMAS H.
Published: October 2005

The extent to which response to environmental change is mediated by species‐specific ecology is an important aspect of the population histories of tropical taxa. During the Pleistocene glacial cycles and associated sea level fluctuations, the Sunda region in Southeast Asia experienced concurrent changes in landmass area and the ratio of forest to open habitat, providing an ideal setting to test the expectation that habitat associations played an important role in determining species’ response to the opportunity for geographic expansion. We used mitochondrial control region sequences and six microsatellite loci to compare the phylogeographic structure and demographic histories of four broadly sympatric species of Old World fruit bats in the genus, Cynopterus. Two forest‐associated species and two open‐habitat generalists were sampled along a latitudinal transect in Singapore, peninsular Malaysia, and southern Thailand. Contrary to expectations based on habitat associations, the geographic scale of population structure was not concordant across ecologically similar species. We found evidence for long and relatively stable demographic history in one forest and one open‐habitat species, and inferred non‐coincident demographic expansions in the second forest and open‐habitat species. Thus, while these results indicate that Pleistocene climate change did not have a single effect on population structure across species, a correlation between habitat association and response to environmental change was supported in only two of four species. We conclude that interactions between multiple factors, including historical and contemporary environmental change, species‐specific ecology and interspecific interactions, have shaped the recent evolutionary histories of Cynopterus fruit bats in Southeast Asia.
DnaA coordinates replication initiation and cell cycle transcription in Caulobacter crescentus
Authors: Hottes Alison K. , Shapiro Lucy , McAdams Harley H.
Published: October 2005

The level of DnaA, a key bacterial DNA replication initiation factor, increases during the Caulobacter swarmer‐to‐stalked transition just before the G1/S transition. We show that DnaA coordinates DNA replication initiation with cell cycle progression by acting as a global transcription factor. Using DnaA depletion and induction in synchronized cell populations, we have analysed global transcription patterns to identify the differential regulation of normally co‐expressed genes. The DnaA regulon includes genes encoding several replisome components, the GcrA global cell cycle regulator, the PodJ polar localization protein, the FtsZ cell division protein, and nucleotide biosynthesis enzymes. In cells depleted of DnaA, the G1/S transition is temporally separated from the swarmer‐to‐stalked cell differentiation, which is normally coincident. In the absence of DnaA, the CtrA master regulator is cleared by proteolysis during the swarmer‐to‐stalked cell transition as usual, but DNA replication initiation is blocked. In this case, expression of gcrA, which is directly repressed by CtrA, does not increase in conjunction with the disappearance of CtrA until DnaA is subsequently induced, showing that gcrA expression requires DnaA. DnaA boxes are present upstream of many genes whose expression requires DnaA, and His6‐DnaA binds to the promoters of gcrA, ftsZ and podJ in vitro. This redundant control of gcrA transcription by DnaA (activation) and CtrA (repression) forms a robust switch controlling the decision to proceed through the cell cycle or to remain in the G1 stage.
Evidence for novel processing of the anaerobically inducible dicistronic focA‐pfl mRNA transcript in Escherichia coli
Authors: Sawers R. Gary
Published: October 2005

The anaerobically inducible dicistronic focA‐pfl operon is transcribed from three co‐ordinately regulated promoters that are located 5′ of the operon. Remarkably, the 5′ ends of four further highly abundant operon‐internal transcripts are located within the focA gene, with a fifth transcript mapping in the intergenic region between focA and pfl. The findings of this study demonstrate that the bulk of these five operon‐internal transcripts are the result of processing. Processing was independent of the broad‐spectrum endoribonucleases associated with mRNA turnover and still occurred when the upstream regulatory region of the operon was replaced with two different heterologous promoters recognized by Escherichia coli core RNA polymerase, including the tetP promoter. However, when the T7Φ10 promoter was introduced upstream of the focA‐pfl operon, mainly full‐length transcript and a minor amount of two processing products were observed. T7 RNA polymerase mutants that exhibit reduced elongation speed did not restore the wild‐type transcript‐processing pattern. Moreover, processing was independent of focA translation. Taken together, these data suggest that processing of the focA‐pfl transcripts occurs by a novel mechanism that might require the action of E. coli core RNA polymerase.
A mutation affecting ASCORBATE PEROXIDASE 2 gene expression reveals a link between responses to high light and drought tolerance
Authors: ROSSEL JAN BART , WALTER PHILIPPA B. , HENDRICKSON LUKE , CHOW WAH SOON , POOLE ANDREW , MULLINEAUX PHILIP M. , POGSON BARRY J.
Published: October 2005

Molecular analyses of plants have revealed a number of genes whose expression changes in response to high light (HL), including the H2O2 scavenger, ASCORBATE PEROXIDASE 2 (APX2). We carried out a screen in Arabidopsis thaliana for lesions that alter HL‐induced expression of APX2 to identify components in abiotic stress signalling pathways. High light was used as it can be instantaneously applied or removed and accurately measured. We identified a number of alx mutations causing altered APX2 expression. Here we describe the gain‐of‐function mutant, alx8, which has constitutively higher APX2 expression and higher levels of foliar abscisic acid (ABA) than wild type. In fact, exogenous ABA increased APX2 expression and the APX2 promoter contains ABA response elements. Furthermore, we have shown that HL stress increases ABA in wild‐type plants, implicating ABA in the regulation of HL‐inducible genes. The alx8 mutant is drought tolerant, exhibits improved water‐use efficiency and a number of drought‐tolerance genes are upregulated. Additionally, alx8 demonstrates the complexity of ABA‐dependent and ABA‐independent transcriptional networks as some components in both pathways are upregulated in alx8. This study provides evidence for common steps in drought and HL stress response pathways.
Using continuous stable isotope measurements to partition net ecosystem CO2 exchange
Authors: ZHANG JIANMIN , GRIFFIS TIMOTHY J. , BAKER JOHN M.
Published: October 2005

Ecosystem‐scale estimation of photosynthesis and respiration using micrometeorological techniques remains an important, yet difficult, challenge. In this study, we combined micrometeorological and stable isotope methods to partition net ecosystem CO2 exchange (FN) into photosynthesis (FA) and respiration (FR) in a corn–soybean rotation ecosystem during the summer 2003 corn phase. Mixing ratios of 12CO2 and 13CO2 were measured continuously using tunable diode laser (TDL) absorption spectroscopy. The dynamics of the isotope ratio of ecosystem respiration (δR), net ecosystem CO2 exchange (δN) and photosynthetic discrimination at the canopy scale (Δcanopy) were examined. During the period of full canopy closure, FN was partitioned into photosynthesis and respiration using both the isotopic approach and the conventional night‐time‐derived regression methodology. Results showed that δR had significant seasonal variation (−32 to −11‰) corresponding closely with canopy phenology. Daytime δN typically varied from −12 to −4‰, while Δcanopy remained relatively constant in the vicinity of 3‰. Compared with the regression approach, the isotopic flux partitioning showed more short‐term variations and was considerably more symmetric about FN. In this experiment, the isotopic partitioning resulted in larger uncertainties, most of which were caused by the uncertainties in δN and the daytime estimate of δR. By sufficiently reducing these uncertainties, the tunable diode laser (TDL)–micrometeorological technique should yield a better understanding of the processes controlling photosynthesis, respiration and ecosystem‐scale discrimination.
Anterior chest wall protrusion as initial presentation of chronic granulomatous disease: a case report
Authors: Mamishi Setareh , Fattahi Fatemeh , Radmanesh Alireza , Mahjoub Fatemeh , Pourpak Zahra
Published: October 2005

Chronic granulomatous disease (CGD) is a rare primary immunodeficiency disease characterized by recurrent life‐threatening bacterial and fungal infections. We report a 4‐month‐old girl with CGD, was firstly presented with an anterior chest wall protrusion because of an aspergillosis mass.