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28064. Urbanization causes shifts in species trait state frequencies

Creator:
Knapp, Sonja, Kühn, Ingolf, Wittig, Rüdiger, Ozinga, Wim A., Poschlod, Peter, and Klotz, Stefan
Type:
article and TEXT
Subject:
compositional data, plant traits, species distribution patterns, urban ecology, urban flora, and vascular plants
Language:
English
Description:
Urbanization is one of the most extreme forms of land transformation. It is supposed to change the frequencies of species trait states in species assemblages. We hypothesize that the flora of urban and rural areas differs in the frequency of trait states and ask which traits enable a plant to cope with the urban environment. We tested our hypothesis in Germany, which was divided into grid-cells of ca 130 km2. We distinguished urbanized (with more than 33% urban land use; n = 59), agricultural (with more than 50% agricultural land use; n = 1365) and semi-natural (with more than 50% forest and semi-natural land use; n = 312) grid-cells and calculated the proportions of plant species per trait state in each grid-cell. Multiple linear regressions explained the log-transformed ratio of one proportion to another with land use (urban, agricultural, semi-natural) and the environmental parameters (climate, topography, soils and geology). Additionally, linear mixed effect models accounted for the effects of land use and biogeography and differences in sample size of the three grid-cell types. Urbanized and rural areas showed clear differences in the proportion of trait states. Urbanized grid-cells had e.g., higher proportions of wind-pollinated plants, plants with scleromorphic leaves or plants dispersed by animals, and lower proportions of insect-pollinated plants, plants with hygromorphic leaves or plants dispersed by wind than other grid-cells. Our study shows that shifts in land use can change the trait state composition of plant assemblages. Far-reaching urbanization might consequently homogenize our flora with respect to trait state frequency.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/

28065. Urbanization effects on carabid diversity in boreal forests

Creator:
Venn, Stephen J., Kotze, D. Johan, and Niemelä, Jari
Type:
article, model:article, and TEXT
Subject:
Boreal forest, carabid beetles, urbanization, urban forests, and urban green space and urban-rural gradient
Language:
English
Description:
Carabid abundance, species richness and diversity were compared along an urban-rural gradient in Helsinki, Finland. Increased urbanization was found to result in significant reductions in species richness, though the reductions in abundance and diversity were not statistically significant. Forest habitat-specialist species were scarce in rural sites and virtually absent from urban and suburban sites. There was no evidence of higher diversity at intermediate disturbance levels (suburban sites), as predicted by the intermediate disturbance hypothesis. Species with flight ability and the ability to utilize open habitat were more predominant in urban and suburban sites. Flightless species were more predominant in rural and suburban sites. Carabid abundance data were sufficient to reveal the negative impact of urbanization, so similar studies could be conducted in regions where carabid taxonomy is poorly known. Species composition patterns do, however, provide invaluable information. To conclude, if biodiversity is to be maintained in urban areas, priority must be given to the provision of those habitat features which are essential for sensitive species, such as decaying wood and wet microhabitats. These must be incorporated into urban green networks in particular, if biodiversity and species other than common generalists are to benefit from them.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

28066. Uric acid contributes greatly to hepatic antioxidant capacity besides protein

Creator:
Mikami, T. and Sorimachi, M.
Type:
article, model:article, and TEXT
Subject:
uric acid, antioxidant, total-radical trapping antioxidant parameter, and allantoin
Language:
English
Description:
Uric acid is the end-product of purine nucleotide metabolism and an increase in uric acid concentration in the body results in hyperuricemia, ultimately leading to gout. However, uric acid is a potent antioxidant and interacts with reactive oxygen species (ROS) to be non-enzymatically converted to allantoin. Uric acid accounts for approximately 60 % of antioxidant capacity in the plasma; however, its contribution to tissue antioxidant capacity is unknown. In this study, the contribution of uric acid to tissue antioxidant capacity and its conversion to allantoin by scavenging ROS in tissue were examined. The results showed that a decrease in hepatic uric acid content via allopurinol administration significantly reduced hepatic total-radical trapping antioxidant parameter (TRAP) content in protein-free cytosol. Additionally, treating protein-free cytosol with uricase led to a further reduction of hepatic TRAP content. Allantoin was also detected in the solution containing protein-free cytosol that reacted with ROS. These findings suggest that in the absence of protein, uric acid contributes greatly to antioxidant capacity in the liver, where uric acid is converted to allantoin by scavenging ROS.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

28067. Uric acid levelis positively associated with NT-proBNP concentration in Slovak heart failure patients

Creator:
Sabaka, P., Dukat, A., Gajdosik, J., Caprnda, M., Bendzala, M., and Simko, F.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
uric acid, heart failure, NT-proBNP, confounding factors, and biochemical marker
Language:
English
Description:
Increased concentration of uric acid (UA) is positively associated with the clinical severity but negatively associated with the prognosis of heart failure (HF). However, data related to the association between UA concentration and N-terminal pro brain natriuretic peptide (NT-proBNP) are still lacking. The aim of the study was to analyze the relationships between UA, NT-proBNP, clearance of creatinine and NYHA function class and echocardiographic variables in the Slovak population of primary care patients diagnosed with HF. The association between UA and NT-proBNP was assessed by multivariate analysis. 848 patients (402 men, 446 women) with HF were included in the study. NT-proBNP correlated with UA in both men and women after adjustment based on age, BMI and glomerular filtration rate (r=0.263, p<0.0001; r=0.293, p<0.0001). UA concentration rose with the severity of the NYHA class and was significantly higher in patients with moderate and severe systolic dysfunctions as well as with diastolic dysfunction in the multivariate analysis. In conclusion, our study in Slovak population with HF has revealed a positive correlation between the concentration of UA and NT-proBNP, and the independency of this association on confounding factors. The results support the role of UA as a biochemical marker of HF severity and prognosis.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

28068. Uridine - an indicator of post-exercise uric acid concentration and blood pressure

Creator:
Dudzinska, W., Lubkowska, A., Dolegowska, B., Suska, M., and Janiak, M.
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, kyselina močová, krevní tlak, tělesná cvičení, uric acid, blood pressure, exercises, uridine, 14, and 612
Language:
English
Description:
Studies have shown that uridine concentration in plasma may be an indicator of uric acid production in patients with gout. It has been also postulated that uridine takes part in blood pressure regulation. Since physical exercise is an effective tool in treatment and prevention of cardio-vascular diseases that are often accompanied by hyperuricemia and hypertension, it seemed advisable to attempt to evaluate the relationship between oxypurine concentrations (Hyp, Xan and UA) and that of Urd and BP after physical exercise in healthy subjects. Sixty healthy men (17.2±1.71 years, BMI 23.2±2.31 kg m-2, VO2max 54.7±6.48 ml kg-1 min-1) took part in the study. The subjects performed a single maximal physical exercise on a bicycle ergometer. Blood for analyses was sampled three times: immediately before exercise, immediately after exercise, and in the 30th min of rest. Concentrations of uridine and hypoxanthine, xanthine and uric acid were determined in whole blood using high-performance liquid chromatography. We have shown in this study that the maximal exercise-induced increase of uridine concentration correlates with the post-exercise increase of uric acid concentration and systolic blood pressure. The results of our study show a relationship between uridine concentration in blood and uric acid concentration and blood pressure. We have been the first to demonstrate that a maximal exercise-induced increase in uridine concentration is correlated with the post-exercise and recovery-continued increase of uric acid concentration in healthy subjects. Thus, it appears that uridine may be an indicator of post-exercise hyperuricemia and blood pressure., W. Dudzinska, A. Lubkowska, B. Dolegowska, M. Suska, M. Janiak., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

28069. Urinary lipocalins in Mastomys coucha

Creator:
Daniszová, Kristina, Janotová, Kateřina, Jedelský, Petr L., Stopka, Pavel, and Dvořáková-Hortová, Kateřina
Type:
article and TEXT
Subject:
Major Urinary Protein and chemical communication
Language:
English
Description:
The presence of large amounts of proteins in mammal urine is usually associated with a pathological condition and indicates serious renal lesions. However, there are few species with obligate proteinuria indicating that they must derive some benefit from this condition. Urinary proteins have been most extensively studied in the house mouse and the rat, and findings to date indicate that their function in intraspecific communication is complex and not yet fully understood. Other proteins of the same protein family as MUPs have been also found in urine of some other rodent species, and still less is known about these. In this study we demonstrate the existence of urinary lipocalins in Mastomys coucha for the first time. Our results support the hypothesis that urinary proteins may play an important role in chemical communication, and level of polymorphism of these proteins in different rodents may help us to understand their specific function.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/

28070. Urinary urea nitrogen excretion during the hyperinsulinemic euglycemic clamp in type 1 diabetic patients and healthy subjects

Creator:
Pavel Wohl, Eva Krušinová, Marta Klementová, Petr Wohl, Simona Kratochvílová, and Terezie Pelikánová
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, diabetologie, inzulín, kalorimetrie, diabetology, insulin, calorimetry, substrate utilization, urinary urea nitrogen excretion, glycemic clamp, indirect calorimetry, 14, and 612
Language:
English
Description:
The hyperinsulinemic euglycemic clamp (HEC) combined with indirect calorimetry (IC) is used for estimation of insulin-stimulated substrate utilization. Calculations are based on urinary urea nitrogen excretion (UE), which is influenced by correct urine collection. The aims of our study were to improve the timing of urine collection during the clamp and to test the effect of insulin on UE in patients with type 1 diabetes (DM1; n=11) and healthy subjects (C; n=11). Urine samples were collected (a) over 24 h divided into 3-h periods and (b) before and during two-step clamp (1 and 10 mIU.kg-1.min-1; period 1 and period 2) combined with IC. The UE during the clamp was corrected for changes in urea pool size (UEc). There were no significant differences in 24-h UE between C and DM1 and no circadian variation in UE in either group. During the clamp, serum urea decreased significantly in both groups (p<0.01). Therefore, UEc was significantly lower as compared to UE not adjusted for changes in urea pool size both in C (p<0.001) and DM1 (p<0.001). While UE did not change during the clamp, UEc decreased significantly in both groups (p<0.01). UEc during the clamp was significantly higher in DM1 compared to C both in period 1 (p<0.05) and period 2 (p<0.01). The UE over 24 h and UEc during the clamp were statistically different in both C and DM1. We conclude that urine collection performed during the clamp with UE adjusted for changes in urea pool size is the most suitable technique for measuring substrate utilization during the clamp both in DM1 and C. Urine collections during the clamp cannot be replaced either by 24-h sampling (periods I-VII) or by a single 24-h urine collection. Attenuated insulin-induced decrease in UEc in DM1 implicates the impaired insulin effect on proteolysis. and Obsahuje bibliografii a bibliografické odkazy
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

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