bluuebunny/crossref_metadata_2025_split huggingface dataset:
Long‐term change in the phenology of spring phytoplankton: species‐specific responses to nutrient enrichment and climatic change
Authors: Thackeray S. J. , Jones I. D. , Maberly S. C. 
Published: February 2008

SummaryA number of studies have shown that spring biological events have advanced in recent decades, and concluded that these changes in phenology are driven by climatic change. Freshwater lakes are sensitive indicators of climate change, where direct effects of climate on physical processes can affect the seasonal timing of planktonic communities. However, many lake ecosystems have also experienced long‐term changes in other ecological pressures that could affect phenology.In this study, long‐term (1955–2003) physical, chemical and biological data from Windermere (UK) were analysed in order to assess the relative effects of a number of coincident pressures on the phenology of two spring diatom taxa. The analysis provides a detailed case study, highlighting the species‐specific drivers that affect the phenology of dominant members of the phytoplankton community.The results showed that, whilst the spring peak biomass of one taxon (Cyclotella) appeared to be advancing as a result of earlier thermal stratification, the advancement of the other (Asterionella) was closely linked with both progressive nutrient enrichment and lake warming. Furthermore, nutrient enrichment explained more variation in phenology than water temperature. Both taxa also reached their peak abundance earlier when the over wintering biomass at the end of the previous year was higher.Patterns of change in phenology and ecological pressures were markedly nonlinear in time, as were the effects of some drivers of seasonal timing. This highlighted a need to relax the restriction of linearity in our analyses of biological seasonality.Synthesis. Phenological shifts may be brought about by local processes, such as eutrophication, as well as by climate change. Even in the same ecosystem different mechanisms may alter the phenology of different species.
The genetic legacy of polyploid Bolivian Daphnia: the tropical Andes as a source for the North and South American D. pulicaria complex
Authors: MERGEAY JOACHIM , AGUILERA XIMENA , DECLERCK STEVEN , PETRUSEK ADAM , HUYSE TINE , DE MEESTER LUC 
Published: February 2008

AbstractWe investigated genetic variation in asexual polyploid members of the water flea Daphnia pulex complex from a set of 12 Bolivian high‐altitude lakes. We used nuclear microsatellite markers to study genetic relationships among all encountered multilocus genotypes, and combined this with a phylogenetic approach using DNA sequence data of three mitochondrial genes. Analyses of mitochondrial gene sequence divergence showed the presence of three very distinct clades that likely represent cryptic undescribed species. Our phylogenetic results suggest that the Daphnia pulicaria group, a complex of predominantly North American species that has diversified rapidly since the Pleistocene, has its origin in South America, as specific tests of topology indicated that all three South American lineages are ancestral to the North American members of this species group. A comparison between variation of nuclear and mitochondrial markers revealed that closely related polyploid nuclear genotypes sometimes belonged to very divergent mitochondrial lineages, while distantly related nuclear genotypes often belonged to the same mitochondrial lineage. This discrepancy suggests that these South American water fleas originated through reciprocal hybridization between different endemic, sexually reproducing parental lineages. It is also likely that polyploidy of the investigated lineages resulted from this hybridization. Nevertheless, no putative diploid parental lineages were found in the studied region.
Monoclonal antibodies reveal changes in predator efficiency with prey spatial pattern
Authors: GRIFFITHS GEORGIANNE J. K. , ALEXANDER COLIN J. , HOLLAND JOHN M. , KENNEDY PETER J. , PERRY JOE N. , SYMONDSON WILLIAM O. C. , WINDER LINTON 
Published: February 2008

AbstractSpatially explicit predator–prey interactions can alter the predatory potential of natural enemies augmented through conservation biological control. To test hypotheses regarding such interactions and predatory efficiency, we used a combination of molecular techniques and mark–release–recapture to study the foraging behaviour of a generalist carabid predator, Poecilus cupreus, in response to spatial patterns of its cereal aphid prey (Metapolophium dirhodum and Sitobion avenae). Beetle and aphid numbers were measured across two grids of sampling locations, within which aphid spatial pattern had been manipulated to generate patchy and more homogenous distributions. Aphid consumption was measured by enzyme‐linked immunosorbent assays (ELISA) of beetle gut contents, using an aphid‐specific monoclonal antibody. Movement and distribution patterns suggest that P. cupreus does not aggregate at, nor instigate prey‐taxis within, aphid patches. However, more than two‐thirds of the 2169 P. cupreus tested by ELISA had consumed aphids and the proportion of beetles containing aphid proteins was positively related to aphid density. Against expectation, the proportion of predators feeding on aphids was greatest where prey were homogenously distributed, and this was attributed to the loss of partial refuges for prey in aphid patches. The functional value of this type of uniform foraging strategy is ideally suited to early colonization of the crop habitat, when aphid numbers are low, before populations build up and form strong spatial patterns.
High genetic differentiation in the alpine plant Campanula alpina Jacq. (Campanulaceae): evidence for glacial survival in several Carpathian regions and long‐term isolation between the Carpathians and the Alps
Authors: RONIKIER M. , CIEŚLAK E. , KORBECKA G. 
Published: February 2008

AbstractA survey of amplified fragment length polymorphism (AFLP) and chloroplast DNA (cpDNA) variation was conducted to elucidate the phylogeography of Campanula alpina, a key species of silicicolous alpine grasslands in the Carpathians with a disjunct distribution in the Eastern European Alps. The Carpathians experienced a different glacial history from the Alps: local glaciers were present only in the highest massifs, while alpine habitats extended over larger areas related to their present distribution in this region. We asked: (i) whether in the Carpathians a high‐mountain plant exhibits a complex phylogeographical structure or rather signatures of recent migrations, and (ii) whether the disjunct part of the species’ distribution in the Alps resulted from a recent colonization from the Carpathians or from a restricted expansion from separate Eastern Alpine refugia. Our study revealed a clear phylogeographical pattern in AFLPs supported by congruent groups of distinct cpDNA haplotypes. Highest genetic differentiation was observed between the Alps and the Carpathians, indicating a long‐term isolation between populations from these two mountain ranges. Further genetic division within the Carpathians suggests that current species’ distribution is composed of several groups which have been isolated from each other for a long period. One genetic break separates Western from Southeastern Carpathian material, which is in line with a classical biogeographical boundary. A further, strongly supported genetic group was identified at the southwestern edge of the Carpathian arch. In the Eastern Alps, genetic traces of glacial survival in separate refugial areas in the calcareous northern part and the siliceous central part were found.
EFFECTS OF VOLUME DEPLETION AND NaHCO3 LOADING ON THE EXPRESSION OF Na+/H+ EXCHANGER ISOFORM 3, Na+ : HCO COTRANSPORTER TYPE 1 AND NITRIC OXIDE SYNTHASE IN RAT KIDNEY
Authors: Ma Seong Kwon , Kang Joo Sam , Bae Eun Hui , Choi Chan , Lee JongUn , Kim Suhn Hee , Choi Ki Chul , Kim Soo Wan 
Published: February 2008

SUMMARY

The effects of volume depletion and NaHCO3 loading on the expression of Na+/H+ exchanger isoform 3 (NHE3), Na+ : cotransporter type 1 (NBC1) and neuronal (n) and inducible (i) isoforms of nitric oxide synthase (NOS) were determined in rat kidney.
Adult male Sprague‐Dawley rats were used. Rats were divided into four groups: (i) euvolaemic (EC); (ii) hypovolaemic (HC); (iii) euvolaemia with NaHCO3 loading (EB); and (iv) hypovolaemia with NaHCO3 loading (HB). The expression of NHE3, NBC1, nNOS and iNOS proteins was determined in the cortex of the kidney by immunoblotting and immunohistochemistry. Tissue content of nitric oxide (NO) metabolites (NOx) were also determined in the cortex using a colourimetric assay.
Compared with the EC group, the expression of NHE3 and NBC1 was increased in the HC group and decreased in the EB group. Comparing the EB and HB groups, the expression of NHE3 and NBC1 was higher in the latter group. The expression of NHE3 was decreased and that of NBC1 was increased in the HB group compared with the HC group. The NOx content and nNOS expression were decreased in the hypovolaemic (HC) and NaHCO3‐loaded (EB and HB) rats. Moreover, the expression of iNOS was decreased in the HB group compared with the other groups.
An altered volume status and NaHCO3 loading may affect the regulation of NHE3 and NBC1 in the kidney and the endogenous NO system may play a role in the observed effects.
STIMULATION OF OESTROGEN RECEPTOR‐EXPRESSING ENDOTHELIAL CELLS WITH OESTROGEN REDUCES PROLIFERATION OF COCULTURED VASCULAR SMOOTH MUSCLE CELLS
Authors: Odenlund Malin , Ekblad Eva , Nilsson Bengt‐Olof 
Published: February 2008

SUMMARY

Oestrogen reduces vascular smooth muscle cell proliferation in mouse vascular injury models. Data on the antiproliferative effect of oestrogen in cultured vascular smooth muscle cells (VSMC) are less conclusive than those obtained in whole animal studies.
In the present study, we investigated the hypothesis that oestrogen‐induced attenuation of VSMC proliferation is facilitated by the presence of endothelial cells (EC) using a coculture system of EC and VSMC.
Treatment with a physiological concentration of oestrogen (17β‐estradiol (E2); 100 nmol/L) had no effect on fetal calf serum (FCS)‐stimulated DNA synthesis in either A7r5 VSMC or bEnd.3 EC. However, stimulation of bEnd. 3 cells with E2 in a coculture system of bEnd.3 and A7r5 cells reduced FCS‐induced DNA synthesis in A7r5 cells by approximately 45%. The nitric oxide synthase inhibitor NG‐nitro‐l‐arginine methyl ester (l‐NAME; 100 µmol/L) did not reverse the oestrogen‐induced attenuation of DNA synthesis. The antiproliferative effect of E2 may be mediated via either oestrogen receptor (ER) α, ERβ or both because the bEnd.3 cells expressed immunoreactivity for both ER subtypes.
These data show that ERα‐ and ERβ‐expressing endothelial cells, which are stimulated with a physiological concentration of oestrogen, release a factor(s) that arrests the proliferation of cocultured VSMC. Oestrogen‐induced attenuation of vascular smooth muscle cell proliferation is not prevented by l‐NAME, suggesting that a mechanism other than endothelial NO is involved.
THE AGE/RAGE AXIS IN DIABETES‐ACCELERATED ATHEROSCLEROSIS
Authors: Jandeleit‐Dahm Karin , Watson Anna , Soro‐Paavonen Aino 
Published: February 2008

SUMMARY

There is increasing evidence that advanced glycation end‐products (AGEs) and their interaction with the receptor RAGE play a pivotal role in atherosclerosis, in particular in the setting of diabetes.
Previous studies have shown that inhibition of AGE accumulation and RAGE expression in diabetes by either reduction of the formation of AGEs or cross‐link breakers was associated with reduced atherosclerosis and renal disease. Advanced glycation end‐products bind to RAGE, thereby leading to activation of a range of inflammatory and fibrotic pathways causing tissue injury. Different splice variants of RAGE exist, including a soluble form that lacks the intracellular domain and fails to induce signal transduction. Therapeutic approaches using soluble RAGE as a decoy binding protein for circulating AGE have been effective in preventing externally induced arterial injury and atherosclerosis in the absence and presence of diabetes.
In order to delineate the role of RAGE in vascular disease in more detail, it was necessary to create RAGE−/– mice, as well as transgenic mice overexpressing RAGE in endothelial cells. It was shown that RAGE overexpression was associated with increased vascular injury, nephropathy and retinopathy.
In contrast, RAGE deletion was associated with partial vascular protection, such as reduced neointima formation after arterial denudation, as well as protection from diabetic nephropathy. The present review summarizes the evidence for RAGE being a pro‐inflammatory and pro‐fibrotic receptor.
Further studies are needed to delineate the effect of RAGE deletion and overexpression in diabetic macrovascular disease. Based on these findings, RAGE could be a potential therapeutic target in combating inflammatory vascular diseases, including diabetes‐associated atherosclerosis.
Effect of seasonal changes in the photosynthates mannitol and laminaran on maturation of Ecklonia cava (Phaeophyceae, Laminariales) in Nishiki Bay, central Japan
Authors: Iwao Toyoki , Kurashima Akira , Maegawa Miyuki 
Published: February 2008

SUMMARYSeasonal changes in the contents of two photosynthates, namely, mannitol and laminaran, were investigated in Ecklonia cava Kjellman with reference to its maturation. The samples were collected from a depth of 8 m in Nishiki Bay, central Japan. The mannitol and laminaran contents in the bladelets were measured. We also determined the content of these photosynthates in the bladelets occupying different positions on the frond and in the sorus and non‐sorus portions of the bladelets. The maturation of sori initiated in July and peaked in October. The content of the two photosynthates in the bladelets was low in winter; this coincided with the active formation of new bladelets. Mannitol levels were high during the beginning of the maturation season in summer. Laminaran, in particular, was present in the bladelets only in summer. The laminaran content was higher in the sorus portions than in the non‐sorus ones; however, the mannitol content was almost equal in both portions. The laminaran content was high only in the bladelets just prior to maturation and in the mature bladelets at the beginning of the maturation season. These results suggested that mannitol and laminaran were important energy sources for the maturation of E. cava from summer to autumn, and laminaran in particular was closely associated with the maturation of reproductive structures.
Oligocarrageenans and tissue‐dependant oxidative burst in Solieria chordalis (Rhodophyceae, Gigartinales)
Authors: Ar Gall Erwan , Cornec Laurence , Deslandes Eric 
Published: February 2008

SUMMARYThe release of hydrogen peroxide by thallus fragments of the rhodophycean Solieria chordalis (C. Agardh) J. Agardh has been documented both in the presence and in the absence of oligosaccharides. Within 1 h, ramuli were able to release large amounts of peroxide in the absence of any chemical stress. Among potential elicitors tested, only degree of polymerization 1 (DP1) and DP7‐8 oligo‐iota‐carrageenans stimulated defense mechanisms in both axes and ramuli as shown by the occurrence of an oxidative burst. Chopping of the tissues had no effect on the intensity of the burst, therefore suggesting that mainly cortical cell layers were involved in the process. After 5 min incubation, a dose of 125 μg mL−1 of an oligomeric mixture containing a large proportion of DP1 units proved to be sufficient to obtain a maximal response. The intensity of the burst was significantly higher with isolated ramuli than with pieces of the axis, with outer peroxide accumulations reaching 200 nmol g−1 fresh weight of treated tissue. Altogether, our results show that S. chordalis is able to react to a simulated pathogen attack by an oxidative burst and that the capacity to carry out an oxidative burst is stronger in ramuli than in axes.
Sebdenia cerebriformis sp. nov. (Sebdeniaceae, Sebdeniales) from the south and western Pacific Ocean
Authors: N'Yeurt Antoine D.R. , Payri Claude E. 
Published: February 2008

SUMMARYA new species of red alga, Sebdenia cerebriformis N'Yeurt et Payri sp. nov. (Sebdeniaceae, Sebdeniales), is described from various localities in the south and western Pacific including Fiji, New Caledonia, the Solomon Islands, Vanuatu, and Indonesia (Java Sea). The new species is characterized by a ruffled thallus with multiple perennial stipitate holdfasts, large conspicuous inner cortical stellate cells, and a lax filamentous medulla.
Seasonal variation on size and chemical constituents of Sargassum sinicola Setchell et Gardner from Bahía de La Paz, Baja California Sur, Mexico
Authors: Rodríguez‐Montesinos Yoloxochitl Elizabeth , Arvizu‐Higuera Dora Luz , Hernández‐Carmona Gustavo 
Published: February 2008

SUMMARYInvestigation on seasonal variation in size and chemical constituents of Sargassum sinicola Setchell et Gardner from Bahía de La Paz, Baja California Sur, Mexico, was carried out from a control bed and compared with an experimental bed with artificial nutrients added. No significant differences were found between the control and experimental thalli for size or chemical composition, except for iodine and raw fiber. For control thalli the results were: size 7.5–56.0 cm, alginate yield 7.2–13.7%, viscosity 58.7–191.7 millipascal seconds (mPa s), mannitol 2.9–8.1%, raw fiber 5.5–7.5% and iodine 0.020–0.141%; while in the experimental thalli the size ranged from 7.5 to 80.3 cm and the alginate yield was 7.8–10.4%, viscosity 41.4–163.4 mPa s, mannitol 2.9–8.3%, raw fiber 5.9–10.7% and iodine 0.021–0.098%. These variations were related to its natural growth cycle, and showed reductions during the senescence period. Results suggest that S. sinicola is not affected by relatively low nutrient concentrations, and could be considered as raw material for alginate production.
Polymorphisms in the promoter region of the basic fibroblast growth factor gene and proliferative diabetic retinopathy in Caucasians with type 2 diabetes
Authors: Petrovič Mojca Globočnik , Krkovič Miha , Osredkar Joško , Hawlina Marko , Petrovič Daniel 
Published: February 2008

AbstractBackground:  Basic fibroblast growth factor (bFGF) expression is implicated in proliferative diabetic retinopathy (PDR). The aim of this study was to investigate the association of genetic polymorphisms (−553T/A, −834T/A and −921C/G) in the promoter region of the bFGF gene with PDR in patients with type 2 diabetes. The second aim was to determine whether serum levels of bFGF are affected by genetic factors.Methods:  In this cross‐sectional case–control study 313 unrelated Caucasians (Slovene population) with type 2 diabetes mellitus were enrolled: 206 patients with PDR and the control group of 107 subjects with type 2 diabetes of duration of more than 10 years who had no clinical signs of diabetic retinopathy. We analysed serum bFGF levels in 78 subjects with type 2 diabetes and 25 subjects without diabetes.Results:  The AT genotype of the −553T/A polymorphism was present in 31 (15.0%) PDR patients and in seven (6.5%) controls (P = 0.03, odds ratio = 2.0, 95% confidence interval = 1.0–3.9). The AT genotype of the −834T/A polymorphism was present in 12 (5.8%) PDR patients and in 15 (14.0%) controls (P = 0.01, odds ratio = 0.4, 95% confidence interval = 0.2–0.8). Significantly higher bFGF serum levels were demonstrated in diabetics with the AT genotype of the −553 polymorphism compared with diabetics with the TT genotype, whereas the −834 and −921 polymorphisms failed to affect serum bFGF levels.Conclusions:  We may conclude that the AT genotype of the 553 T/A polymorphism was associated with PDR in Caucasians with type 2 diabetes, therefore it might be used as a genetic marker of PDR in Caucasians, whereas carriage of the AT genotype of the −834 T/A polymorphism might decrease PDR risk.
Delirium among elderly general medical patients in a New Zealand hospital
Authors: Holden J. , Jayathissa S. , Young G. 
Published: February 2008

AbstractBackground:  Overseas studies suggest that delirium is a common and serious health problem of hospitalized elderly. There is very little information in New Zealand.Aims:  To study prospectively the frequency and effect of delirium on a cohort of elderly general medical patients.Methods:  Over 2 months, 317 patients were admitted to general medical wards; 70% were aged 65 years and above. These patients were screened for delirium. Comparisons were made between the delirious and non‐delirious patients.Results:  Fifty‐six of the 216 patients screened had delirium. The prevalence and incidence of delirium were 23.4 and 5.7%, respectively. Thirty‐one per cent of delirious patients had a previous history of dementia; 48% of delirious patients had multiple precipitants, most commonly infections. Delirium was associated with higher complication rates – 94 versus 39% in the non‐delirious patients – and a doubling in the length of hospital stay. Over 50% of delirious patients required increased supports on discharge with a general trend towards higher frequency of institutionalization. The presence of delirium was associated with increased use of neuroleptic medications, special nursing care, cot sides and restraints. A non‐significant trend towards increased mortality was seen in the delirious group.Conclusions:  Delirium is a common health problem in elderly patients, associated with multiple adverse outcomes. This study highlighted the prognostic importance of diagnosing delirium. Recommendations included improved health professional education, development of guidelines including rational use of neuroleptic medication and measures to improve follow up for these patients.
Prevalence, detection and drug treatment of hypertension in a rural Australian population: the Greater Green Triangle Risk Factor Study 2004–2006
Authors: Janus E. D. , Bunker S. J. , Kilkkinen A. , Namara K. Mc , Philpot B. , Tideman P. , Tirimacco R. , Laatikainen T. K. , Heistaro S. , Dunbar J. A. 
Published: February 2008

AbstractBackground:  Hypertension is an important risk factor for cardiovascular disease; however, limited findings are available on its detection and management in rural Australia.Aim:  To assess the prevalence, awareness and treatment of hypertension in a rural South‐East Australian population.Methods:  Three cross‐sectional surveys in Limestone Coast, Corangamite Shire and Wimmera regions during 2004–2006 using a random population sample (n = 3320, participation rate 49%) aged 25–74 years. Blood pressure was measured by trained nurses. Information on history of hypertension and medication was obtained by questionnaires. Hypertension was defined as systolic blood pressure ≥140 mmHg and/or diastolic blood pressure ≥90 mmHg and/or on antihypertensive drug treatment.Results:  Overall, one‐third of participants had hypertension; of these, two‐thirds, 54% (95% confidence interval (CI) 47–60) of men and 71% (95% CI 65–77) of women, were aware of their condition. Half of the participants with hypertension were treated and nearly half of these were controlled. Both treatment and control were more common in women (60%, 95% CI 54–67 and 55%, 95% CI 47–64) compared with men (42%, 95% CI 36–49 and 35%, 95% CI 26–44). Monotherapy was used by 55% (95% CI 48–61) of treated hypertensives. Angiotensin‐converting enzyme inhibitors were the most frequently used class of antihypertensive drugs in men, whereas angiotensin‐converting enzyme inhibitors, angiotensin receptor antagonists and diuretics were all widely used among women.Conclusion:  This study emphasizes suboptimal detection and treatment of hypertension, especially in men, in rural Australia.