bluuebunny/crossref_metadata_2025 huggingface dataset:
The effect of fungicides for seed treatment on germination of barley
Authors: Stevanovic Vesna , Indjic Dusanka , Knezevic Branislav
Published: October 2009

The application of chemicals, such as fungicides for seed treatment, is one of the most reliable and perhaps most efficient measures for integrated preservation of crops, and its practicing has become a legal obligation for all seed producers. This investigation was carried out in the laboratory for seed quality and phytopathology of the Small Grains Research Center in Kragujevac. The objective was to establish the effect of fungicides on germination energy and seed germ inability (determined after treatments). Two varieties were tested due to a possibility of specific sensitivities of some varieties, so that the results acquired on one variety would not necessarily be valid for another one. Fungicides based on active ingredients from the triasol chemical group had different effects on the energy of germination of barley seeds. Applying Raxil S040-FS, the average germination of barley seeds was 79.3% for the variety Record, and 91.3% for the Grand variety. The variety Record achieved a lower value than the minimum for barley seed germination (88%) stipulated by the Rules on Seed Quality of Agricultural Crops. Regardless of barley type, the product Raxil S040-FS showed a statistically significant effect on the number of atypical seedlings and increase in the number of non-germinated seeds, compared to the control.
Gestational Diabetes Mellitus Resulting From Impaired β-Cell Compensation in the Absence of FoxM1, a Novel Downstream Effector of Placental Lactogen
Authors: Zhang Hongjie , Zhang Jia , Pope Christine F. , Crawford Laura A. , Vasavada Rupangi C. , Jagasia Shubhada M. , Gannon Maureen
Published: October 2009

OBJECTIVE

The objectives of the study were to determine whether the cell cycle transcription factor, FoxM1, is required for glucose homeostasis and β-cell mass expansion in maternal islets during pregnancy and whether FoxM1 is essential for placental lactogen (PL)-induced β-cell proliferation.

RESEARCH DESIGN AND METHODS

β-Cell mass, β-cell proliferation, and glucose homeostasis were assessed in virgin, pregnant, and postpartum mice with a pancreas-wide Foxm1 deletion (FoxM1Δpanc). Wild-type islets were cultured with or without PL and examined for Foxm1 induction. Transgenic mice overexpressing PL in β-cells were bred with FoxM1Δpanc mice, and β-cell proliferation was examined.

RESULTS

Foxm1 was upregulated in maternal islets during pregnancy. In contrast to controls, β-cell proliferation did not increase in pregnant FoxM1Δpanc females. Mutant islets showed increased Menin and nuclear p27. FoxM1Δpanc females developed gestational diabetes mellitus as pregnancy progressed. After parturition, euglycemia was restored in FoxM1Δpanc females, but islet size was significantly reduced. Strikingly, β-cell mass was normal in postpartum FoxM1Δpanc pancreata due to a combination of increased β-cell size and islet neogenesis. Evidence for neogenesis included increased number of endocrine clusters, increased proportion of smaller islets, and increased neurogenin 3 or insulin expression in cells adjacent to ducts. PL induced Foxm1 expression in cultured islets, and FoxM1 was essential for PL-mediated increases in β-cell proliferation in vivo.

CONCLUSIONS

FoxM1 is essential for β-cell compensation during pregnancy. In the absence of increased β-cell proliferation, neogenesis is induced in postpartum FoxM1Δpanc pancreata. Our results suggest that FoxM1 functions downstream of PL to mediate its effects on β-cell proliferation.
High-Throughput Assay for Modulators of Mitochondrial Membrane Potential Identifies a Novel Compound With Beneficial Effects on db/db Mice
Authors: Qiu Bei-Ying , Turner Nigel , Li Yuan-Yuan , Gu Min , Huang Meng-Wei , Wu Fang , Pang Tao , Nan Fa-Jun , Ye Ji-Ming , Li Jing-Ya , Li Jia
Published: October 2009

OBJECTIVE

Recently, several drugs have been shown to exert beneficial effects for metabolic syndrome through mild regulation of mitochondrial function. Hence, we explored a strategy of targeting mitochondrial function to improve glucose and lipid metabolism.

RESEARCH DESIGN AND METHODS

Mitochondrial membrane potential (Δψm) is a marker of mitochondrial function; therefore, we set up a high-throughput screening assay of Δψm in L6 myotubes. The effects of a selected lead compound were investigated in vitro and in vivo in relation to metabolic syndrome.

RESULTS

A novel small-molecule compound, C1, was identified through this high-throughput screening. C1 depolarized Δψm in L6 myotubes without cytotoxicity and led to increased cellular AMP-to-ATP ratio, activation of AMP-activated protein kinase (AMPK), and enhanced glucose uptake. It also stimulated the AMPK pathway in HepG2 cells, leading to decreased lipid content. Intriguingly, C1 inhibited respiration in L6 myotubes but did not affect respiration in isolated muscle mitochondria, suggesting that it may depolarize Δψm indirectly by affecting the supply of electron donors. Acute administration of C1 in C57BL/6J mice markedly increased fat oxidation and the phosphorylation of AMPK and acetyl-CoA carboxylase in the liver. In diabetic db/db mice, chronic administration of C1 significantly reduced hyperglycemia, plasma fatty acids, glucose intolerance, and the mRNA levels of phosphoenolpyruvate carboxykinase and glucose-6-phosphatase in the liver.

CONCLUSIONS

Our results demonstrate a novel small molecule that mildly depolarizes Δψm and is able to improve glucose and lipid metabolism to exert beneficial effects for metabolic syndrome. These findings suggest that compounds regulating mitochondrial function may have therapeutic potential for type 2 diabetes.
Age at Onset of Type 1 Diabetes in Parents and Recurrence Risk in Offspring
Authors: Harjutsalo Valma , Lammi Niina , Karvonen Marjatta , Groop Per-Henrik
Published: October 2009

OBJECTIVE

Our aim was to study the recurrence risk of type 1 diabetes in the offspring of parents with adult-onset (15–39 years) type 1 diabetes and to evaluate the transmission of diabetes within a continuum of parental age at onset of diabetes from childhood to adulthood.

RESEARCH DESIGN AND METHODS

Diabetes status of all offspring (n = 9,636) in two Finnish cohorts of parents with type 1 diabetes was defined until the end of year 2007. Cumulative incidences of type 1 diabetes among the offspring were estimated, and several factors contributing to the risk were assessed.

RESULTS

During 137,455 person-years, a total of 413 offspring were diagnosed with type 1 diabetes. The cumulative incidence by 20 years was 4.0% (95% CI 3.1–4.8) for the offspring of parents with adult-onset diabetes. The risk was equal according to the sex of the parents. The cumulative incidence decreased in parallel with the increase in age at onset of diabetes in the fathers. In the offspring of diabetic mothers, the risk was equal regardless of the age at onset of diabetes. However, the reduced risk in the maternal offspring was most pronounced in the daughters of the mothers with a diagnosis age <10 years.

CONCLUSIONS

Type 1 diabetes transmission ratio distortion is strongly related to the sex and age at onset of diabetes in the diabetic parents.
Chronic Peripheral Hyperinsulinemia in Type 1 Diabetic Patients After Successful Combined Pancreas-Kidney Transplantation Does Not Affect Ectopic Lipid Accumulation in Skeletal Muscle and Liver
Authors: Stadler Marietta , Anderwald Christian , Pacini Giovanni , Zbýň Štefan , Promintzer-Schifferl Miriam , Mandl Martina , Bischof Martin , Gruber Stephan , Nowotny Peter , Luger Anton , Prager Rudolf , Krebs Michael
Published: October 2009

OBJECTIVE

So far it is unclear whether chronic peripheral hyperinsulinemia per se might contribute to ectopic lipid accumulation and consequently insulin resistance. We investigated the effects of systemic instead of portal insulin release in type 1 diabetic patients after successful pancreas-kidney transplantation (PKT) with systemic venous drainage on the intracellular lipid content in liver and soleus muscle, endogenous glucose production (EGP), and insulin sensitivity.

RESEARCH DESIGN AND METHODS

In nine PKT patients and nine matching nondiabetic control subjects, intrahepatocellular lipids (IHCLs) and intramyocellular lipids (IMCLs) were measured using 1H nuclear magnetic resonance spectroscopy. Fasting EGP was measured using d-[6,6-2H2]glucose tracer dilution. A 3-h 75-g oral glucose tolerance test (OGTT) allowed us to assess kinetics of glucose, free fatty acids, insulin, and C-peptide concentrations in plasma and to calculate the clamp-like index (CLIX) for insulin sensitivity and the hepatic insulin resistance (HIR) index.

RESULTS

The PKT patients displayed approximately twofold increased fasting insulin (20 ± 6 vs. 9 ± 3 μU/ml; P < 0.0002) compared with that in nondiabetic control subjects and ∼10% increased fasting glucose (P < 0.02) concentrations, but during the OGTT areas under the concentration curves of C-peptide and insulin were similar. IHCL (PKT, 2.9 ± 2.5%; nondiabetic control subjects, 4.4 ± 6.6%), IMCL (PKT, 1.0 ± 0.4%; nondiabetic control subjects, 1.0 ± 0.5%), CLIX (PKT, 8 ± 2; nondiabetic control subjects, 7 ± 3), HIR (PKT, 25.6 ± 13.2; nondiabetic control subjects, 35.6 ± 20 [mg · min−1 · kg−1] × [μU/ml]), and EGP (PKT, 1.6 ± 0.2; nondiabetic control subjects, 1.7 ± 0.2 mg · min−1 · kg−1) were comparable between PKT patients and nondiabetic control subjects. IHCL was negatively correlated with CLIX in all participants (r = −0.55; P < 0.04).

CONCLUSIONS

Despite fasting peripheral hyperinsulinemia because of systemic venous drainage, type 1 diabetic patients after PKT show similar IHCL, IMCL, insulin sensitivity, and fasting EGP in comparison with nondiabetic control subjects. These results suggest that systemic hyperinsulinemia per se does not cause ectopic lipid accumulation in liver and skeletal muscle.
Nephrin Is Expressed on the Surface of Insulin Vesicles and Facilitates Glucose-Stimulated Insulin Release
Authors: Fornoni Alessia , Jeon Jongmin , Varona Santos Javier , Cobianchi Lorenzo , Jauregui Alexandra , Inverardi Luca , Mandic Slavena A. , Bark Christina , Johnson Kevin , McNamara George , Pileggi Antonello , Molano R. Damaris , Reiser Jochen , Tryggvason Karl , Kerjaschki Dontscho , Berggren Per-Olof , Mundel Peter , Ricordi Camillo
Published: October 2009

OBJECTIVE

Nephrin, an immunoglobulin-like protein essential for the function of the glomerular podocyte and regulated in diabetic nephropathy, is also expressed in pancreatic β-cells, where its function remains unknown. The aim of this study was to investigate whether diabetes modulates nephrin expression in human pancreatic islets and to explore the role of nephrin in β-cell function.

RESEARCH DESIGN AND METHODS

Nephrin expression in human pancreas and in MIN6 insulinoma cells was studied by Western blot, PCR, confocal microscopy, subcellular fractionation, and immunogold labeling. Islets from diabetic (n = 5) and nondiabetic (n = 7) patients were compared. Stable transfection and siRNA knockdown in MIN-6 cells/human islets were used to study nephrin function in vitro and in vivo after transplantation in diabetic immunodeficient mice. Live imaging of green fluorescent protein (GFP)-nephrin–transfected cells was used to study nephrin endocytosis.

RESULTS

Nephrin was found at the plasma membrane and on insulin vesicles. Nephrin expression was decreased in islets from diabetic patients when compared with nondiabetic control subjects. Nephrin transfection in MIN-6 cells/pseudoislets resulted in higher glucose-stimulated insulin release in vitro and in vivo after transplantation into immunodeficient diabetic mice. Nephrin gene silencing abolished stimulated insulin release. Confocal imaging of GFP-nephrin–transfected cells revealed nephrin endocytosis upon glucose stimulation. Actin stabilization prevented nephrin trafficking as well as nephrin-positive effect on insulin release.

CONCLUSIONS

Our data suggest that nephrin is an active component of insulin vesicle machinery that may affect vesicle-actin interaction and mobilization to the plasma membrane. Development of drugs targeting nephrin may represent a novel approach to treat diabetes.
Insulin Resistance Is Associated With Higher Intramyocellular Triglycerides in Type I but Not Type II Myocytes Concomitant With Higher Ceramide Content
Authors: Coen Paul M. , Dubé John J. , Amati Francesca , Stefanovic-Racic Maja , Ferrell Robert E. , Toledo Frederico G.S. , Goodpaster Bret H.
Published: October 2009

OBJECTIVE

We tested the primary hypotheses that sphingolipid and diacylglycerol (DAG) content is higher within insulin-resistant muscle and that the association between intramyocellular triglycerides (IMTG) and insulin resistance is muscle fiber type specific.

RESEARCH DESIGN AND METHODS

A nested case-control analysis was conducted in 22 obese (BMI >30 kg/m2) women who were classified as insulin-resistant (IR; n = 12) or insulin-sensitive (IS; n = 10), determined by hyperinsulinemic-euglycemic clamp (>30% greater in IS compared with IR, P < 0.01). Sphingolipid and DAG content was determined by high-performance liquid chromatography–tandem mass spectrometry. Fiber type–specific IMTG content was histologically determined. Gene expression was determined by quantitative PCR.

RESULTS

Total (555 ± 53 vs. 293 ± 54 pmol/mg protein, P = 0.004), saturated (361 ± 29 vs. 179 ± 34 pmol/mg protein, P = 0.001), and unsaturated (198 ± 29 vs. 114 ± 21 pmol/mg protein, P = 0.034) ceramides were higher in IR compared with IS. DAG concentrations, however, were similar. IMTG content within type I myocytes, but not type II myocytes, was higher in IR compared with IS subjects (P = 0.005). Insulin sensitivity was negatively correlated with IMTG within type I myocytes (R = −0.51, P = 0.026), but not with IMTG within type II myocytes. The proportion of type I myocytes was lower (41 vs. 59%, P < 0.01) in IR subjects. Several genes involved in lipid droplet and fatty acid metabolism were differentially expressed in IR compared with IS subjects.

CONCLUSIONS

Human skeletal muscle insulin resistance is related to greater IMTG content in type I but not type II myocytes, to greater ceramide content, and to alterations in gene expression associated with lipid metabolism.
Low Muscle Glycogen and Elevated Plasma Free Fatty Acid Modify but Do Not Prevent Exercise-Induced PDH Activation in Human Skeletal Muscle
Authors: Kiilerich Kristian , Gudmundsson Mikkel , Birk Jesper B. , Lundby Carsten , Taudorf Sarah , Plomgaard Peter , Saltin Bengt , Pedersen Per A. , Wojtaszewski Jorgen F.P. , Pilegaard Henriette
Published: October 2009

OBJECTIVE

To test the hypothesis that free fatty acid (FFA) and muscle glycogen modify exercise-induced regulation of PDH (pyruvate dehydrogenase) in human skeletal muscle through regulation of PDK4 expression.

RESEARCH DESIGN AND METHODS

On two occasions, healthy male subjects lowered (by exercise) muscle glycogen in one leg (LOW) relative to the contra-lateral leg (CON) the day before the experimental day. On the experimental days, plasma FFA was ensured normal or remained elevated by consuming breakfast rich (low FFA) or poor (high FFA) in carbohydrate, 2 h before performing 20 min of two-legged knee extensor exercise. Vastus lateralis biopsies were obtained before and after exercise.

RESULTS

PDK4 protein content was ∼2.2- and ∼1.5-fold higher in LOW than CON leg in high FFA and low FFA, respectively, and the PDK4 protein content in the CON leg was approximately twofold higher in high FFA than in low FFA. In all conditions, exercise increased PDHa (PDH in the active form) activity, resulting in similar levels in LOW leg in both trials and CON leg in high FFA, but higher level in CON leg in low FFA. PDHa activity was closely associated with the PDH-E1α phosphorylation level.

CONCLUSIONS

Muscle glycogen and plasma FFA attenuate exercise-induced PDH regulation in human skeletal muscle in a nonadditive manner. This might be through regulation of PDK4 expression. The activation of PDH by exercise independent of changes in muscle glycogen or plasma FFA suggests that exercise overrules FFA-mediated inhibition of PDH (i.e., carbohydrate oxidation), and this may thus be one mechanism behind the health-promoting effects of exercise.
Hippocampal Volumes in Youth With Type 1 Diabetes
Authors: Hershey Tamara , Perantie Dana C. , Wu Jenny , Weaver Patrick M. , Black Kevin J. , White Neil H.
Published: October 2009

OBJECTIVE

Hippocampal neurons in adult animals and humans are vulnerable to severe hypoglycemia and hyperglycemia. Effects are hypothesized to be exacerbated during development, but existing studies on developing human brains are limited. We examined whether hypoglycemia or hyperglycemia experienced during brain development in humans affects hippocampal volumes.

RESEARCH DESIGN AND METHODS

We analyzed T1-weighted magnetic resonance images in 95 youth with type 1 diabetes and 49 sibling control subjects aged 7–17 years. Youth with diabetes were categorized as having 0 (n = 37), 1–2 (n = 41), or 3 or more (3+; n = 17) prior severe hypoglycemic episodes. Hyperglycemia exposure was estimated from median lifetime A1C, weighted for duration of diabetes. Stereologic measurements of hippocampal volumes were performed in atlas-registered space to correct for whole brain volume.

RESULTS

Greater exposure to severe hypoglycemia was associated with larger hippocampal volumes (F [3,138] = 3.6, P = 0.016; 3+ larger than all other groups, P < 0.05). Hyperglycemia exposure was not associated with hippocampal volumes (R2 change = 0.003, F [1,89] = 0.31, P = 0.58, semipartial r = 0.06; one outlier removed for high median A1C), and the 3+ severe hypoglycemia group still had larger hippocampal volumes after controlling for age of onset and hyperglycemia exposure (main effect of hypoglycemia category, F [2,88] = 6.4, P = 0.002; 3+ larger than all other groups, P < 0.01).

CONCLUSIONS

Enlargement of the hippocampus may reflect a pathological reaction to hypoglycemia during brain development, such as gliosis, reactive neurogenesis, or disruption of normal developmental pruning.
Cloud point extraction and preconcentration of gold in geological matrices prior to flame atomic absorption determination
Authors: El-Naggar Wifky , Lasheen Taysseer , Nouh El-Said , Ghonaim Ahmed
Published: October 2009

Brilliant green was used as a complexing agent in cloud point extraction (CPE) and applied for selective preconcentration of trace amounts of gold in geological matrices. The analyte in the initial aqueous solution was acidified with hydrochloric acid (0.1 M) and octylphenoxypolyethoxyethanol (Triton X-114) was added as a surfactant. After phase separation, based on the cloud point separation of the mixture, the surfactant rich phase was diluted with methanol and the analyte determined in the surfactant rich phase by flame atomic absorption spectrometry (FAAS). After optimization of the complexation and extraction conditions, a preconcentration factor of 31 was obtained for only 10 mL of sample. The analytical curve was linear in the range of 3–1000 ng mL−1 and the limit of detection was 1.5 ng mL−1. The proposed method was applied to the determination of gold in geological samples.
Metalloantibiotics: Synthesis, characterization and antimicrobial evaluation of bismuth-fluoroquinolone complexes against Helicobacter pylori
Authors: Shaikh Anwar , Giridhar Rajani , Megraud Francis , Yadav Mange
Published: October 2009

Metalloantibiotics: Synthesis, characterization and antimicrobial evaluation of bismuth-fluoroquinolone complexes againstHelicobacter pylori

Novel organometallic compounds have been prepared by complexing the fluoroquinolones, norfloxacin, ofloxacin, ciprofloxacin, sparfloxacin, lomefloxacin, pefloxacin and gatifloxacin, with bismuth. The complexes were characterized by UV, IR, atomic absorption spectroscopy, elemental analysis, differential scanning calorimetry, thermogravimetric analysis and mass spectrometry. Their antibacterial potential againstHelicobacter pyloriand other microorganisms was investigated. These compounds were found to possess strong activity againstHelicobacter pyloriwith a minimum inhibitory concentration of 0.5 mg L-1. They also exhibited moderate activity againstEscherichia coli, Staphylococcus aureus, Bacillus pumilusandStaphylococcus epidermidis.These bismuth-fluoroquinolone complexes have the potential to be developed as drugs againstH. pylorirelated ailments.
Catalytic performances of cross-linking humic acids supported Pd/Ni bimetallic catalyst for heck reaction
Authors: Xu Qijie , Zhang Lei , Shi Wenzhong , Cui Yuanchen
Published: October 2009

Catalytic performances of cross-linking humic acids supported Pd/Ni bimetallic catalyst for heck reaction

The cross-linking humic acids (CL-HAs), epichlorohydrin as the cross-linking reagent and the supported Pd/Ni bimetallic catalysts (CL-HAs-Pd/Ni) were prepared and characterized by IR, AAS, XPS, TEM. The effects of reaction time, temperature, base, solvent and the amount of catalyst on the properties of the catalyst were studied. These catalysts could catalyze the Heck reaction of aryl halides and substituted aryl halides with acrylic acids or styrene successfully; the yields were all above 95%.
Gait Variability Detects Women in Early Postmenopause With Low Bone Mineral Density
Authors: Palombaro Kerstin M. , Hack Laurita M. , Mangione Kathleen Kline , Barr Ann E. , Newton Roberta A. , Magri Francesca , Speziale Theresa
Published: October 2009

Background

Women in early postmenopause and with low bone mineral density (BMD) may exhibit early markers for physical frailty as a result of sarcopenia and osteopenia.

Objective

The purpose of this study was to determine whether women in early postmenopause and with low BMD exhibit decreased physical performance and differences in gait variability and fall and fracture rates.

Design

This study was an observational cohort design with participants assigned to groups on the basis of BMD status.

Methods

Fifty-four women, 31 with low BMD and 23 with normal BMD, participated. This study was conducted in a university research facility. Physical performance was measured by assessment of dynamic balance (timed backward tandem walk test), strength (handheld dynamometry of isometric quadriceps muscle force production), and free gait speed. Gait variability was assessed on the basis of the coefficient of variation for temporal-spatial gait characteristics. Falls and fractures were assessed for the year after initial testing.

Results

Significant between-group differences were found for step time and stance time variability.

Limitations

The limitations of this study included group assignment on the basis of the results of the most recent bone density scan within the preceding 2 years.

Conclusions

Women in early postmenopause and with low BMD exhibited increased gait variability in step time and stance time but did not exhibit differences in balance, strength, or gait speed. Gait variability may be more sensitive for detecting differences in women in early postmenopause and with or without low BMD than more typical measures of physical performance.
Factors Affecting Predation of Red Foxes Vulpes vulpes on Brown Hares Lepus europaeus During the Breeding Season in Poland
Authors: Panek Marek
Published: October 2009

The aim of my study was to estimate the effect of brown hare Lepus europaeus density, vole abundance and habitat diversity on the occurrence of hares in the diet of red fox Vulpes vulpes during the breeding season in agricultural landscapes. I used the average number of adult hares found among food remains scattered around a number of breeding dens of foxes (10–24/year), and analysed its temporal variation during 1997–2006 in an area located in western Poland; furthermore, I analysed the spatial variation based on results from 21 areas in various other regions of the country. Spring hare density, vole abundance index (logarithm of the number of burrow entrances/km) and habitat diversity (number of structural elements/km) were estimated using line transects of 20–61 km. In the low hare density area (5–10 individuals/km2) in western Poland, the number of hares/fox den was influenced by hare density rather than by vole abundance. In the various areas with high hare densities (11–28 individuals/km2), multiple regression analysis showed a positive effect of hare density (R2=40%) and a negative effect of vole abundance index (R2=24%) on the number of hares/fox den, whereas the effect of habitat diversity index (R2=13%) was only close to being significant. In the case of low hare density range (1–10 individuals/km2), the number of hares/fox den decreased with the habitat diversity index (R2=56%). Therefore, proper habitat management in agricultural areas should lead to a reduction of red fox pressure on brown hare, especially in areas with low‐density hare populations.
Separating Wild from Domestic American Mink Neovison vison Based on Skull Morphometries
Authors: Tamlin Ashley L. , Bowman Jeff , Hackett David F.
Published: October 2009

Domestication can change animal traits such as skull size and shape. Given that domestic American mink Neovison vison may escape from farms within the native range of wild mink, we were interested in determining whether 1) skull characteristics differed between wild and domestic mink, and 2) free ranging mink in Ontario had skull features characteristic of domestic animals. Contrary to previous research, we found no effect of domestication on braincase volume or muzzle length in mink. We did, however, find that skulls of domestic mink were larger than those of wild mink and that domestic skulls had narrowed postorbital constrictions (POC). A model using both condylobasal length (CBL) and POC correctly classified the origin of 100% of male skulls and 90% of female skulls in an external data set. A POC‐only model was less successful, however, correctly classifying 68% and 70% of male and female skulls, respectively. In a field application of the two‐term model, only one of 109 skulls was identifed as being of farm origin. With the POC‐only model, however, 12 skulls were classified as being from domestic animals. Where size differences are expected (for example, with recently escaped animals), the model should be effective for identifying domestic mink. However, the utility of CBL and POC for identifying domestic‐origin or hybrid animals that have been born in the wild depends on a key uncertainty, namely, the extent to which these traits have a genetic basis.
Wildlife Community Patterns in Relation to Landscape Structure and Environmental Gradients in a Swedish Boreal Ecosystem
Authors: Wallgren Märtha , Bergström Roger , Danell Kjell , Skarpe Christina
Published: October 2009

Many environmental patterns that may have profound effects on wildlife communities occur at the landscape scale, e.g. habitat fragmentation, human demography and distribution of various resources. In order to understand how alterations of such patterns could influence e.g. wildlife species occurrences and community composition, it is important to first study these relationships empirically and at the appropriate scale. We surveyed the wildlife community in a boreal ecosystem in central Sweden using pellet group counts, while walking ‘wildlife triangles’. Our main aim was to investigate how the distribution of medium‐ and large‐sized wild mammals and large‐sized forest birds were affected by environmental variables at the landscape scale. In 2001–2003, pellet groups of mammals and forest birds were counted on 211 triangular routes with a perimeter of 4+4+4 km. The pellet groups which had accumulated after leaf fall were counted in spring. The environmental properties of each triangle, including information on latitude, altitude, infrastructure, land cover, forest type and forest stage, were determined using GIS maps. Statistical analyses involved mainly ordination (Principal Component Analysis, PCA). Significant environmental variables explaining the wildlife community composition and distribution in the boreal ecosystem were altitude, clear‐felling and infrastructure. Our conclusion, however, is that most boreal mammal and forest bird species are habitat generalists and show little spatial pattern in distributions at the landscape scale. This indicates that habitat selectiveness probably occurs at a local scale in the boreal forest. Ultimately, our conclusion provides important direction for e.g. conservation measures and wildlife management.
The Development of a Molecular Assay to Distinguish Droppings of Black Grouse Tetrao tetrix from those of Capercaillie Tetrao urogallus and Red Grouse Lagopus Lagopus Scoticus
Authors: A'Hara Stuart W. , Hancock Mark , Piertney Stuart B. , Cottrell Joan E.
Published: October 2009

Counts of faecal droppings are a useful approach for the non‐invasive monitoring of species presence and abundance. However, for game birds, it is often difficult to determine unequivocally the species origin of the droppings. Here, we compare the utility of two molecular approaches which exploit variation in the cytochrome b region of mitochondrial DNA to distinguish the droppings of black grouse Tetrao tetrix from those of red grouse Lagopus lagopus scoticus and capercaillie Tetrao urogallus. A sensitive detection method is required as DNA extracts from droppings tend to yield poor quality DNA in low copy number. The first approach adopted a real‐time PCR method in which primers were used to amplify a small fragment in the mitochondrial cytochrome b region, and fluorogenic probes complementary to species‐specific SNPs were designed. The success of this test was compared with that of conventional, end point PCR followed by DNA sequencing of a 346 bp mitochondrial cytochrome b region containing the shorter sequence used in the real‐time PCR test. In samples which produced results with both the real‐time and sequencing approaches, the results were always in agreement. However, the sequencing approach, when used in conjunction with hot‐start Taq PCR, proved superior as it worked in a greater number of samples than the real‐time method. The length of clear sequence generated allowed secure identification based on several species‐specific SNPs. The development of a molecular approach based on a commercially available DNA extraction kit followed by off‐site sequencing now offers a secure method of identifying the species origin of field‐collected grouse droppings and requires only basic knowledge of molecular techniques and inexpensive molecular equipment.
Fluctuating Asymmetry in elk Cervus elaphus Antlers is Unrelated to Environmental Conditions in the Greater Yellowstone Ecosystem
Authors: Eggeman Scott L. , Hebblewhite Mark , Cunningham Julie , Hamlin Ken
Published: October 2009

Fluctuating asymmetry (FA) is a measure of the deviation from perfect bilateral symmetry, and has been used across mammals as a reliable indicator of environmental stress during growth and development. Antler size and symmetry can be an indicator of individual fitness and social rank among ungulates such as the North American elk Cervus elaphus. When environmental conditions are favourable, ungulates allocate additional resources to antler development to increase secondary sexual traits and enhance reproduction. We tested whether there was an appreciable change in antler length and the number of points as extreme climatic conditions (e.g. heavy snow and drought) reduced the nutritional condition of elk using 8,690 antler measurements collected at hunter check stations in south‐central Montana surrounding the Greater Yellowstone Ecosystem (GYE) during 1982–2006. We also hypothesized that FA in elk antlers would increase at high elk density because of density‐dependent competition for food. We developed a priori general linear models of FA expressed as a function of climate covariates, elk density and relevant ecological interactions between the variables. In contrast to previous studies, especially of European ungulates, our results show little support for strong effects of climate or density on FA in length or the number of points. Thus, North American elk do not appear to respond to environmental variation by varying allocation to antler growth, instead they show stronger age‐related effects on FA.
Comparison of Grizzly Bear Ursus arctos Demographics in Wilderness Mountains Versus a Plateau with Resource Development
Authors: Ciarniello Lana M. , Boyce Mark S. , Seip Dale R. , Heard Douglas C.
Published: October 2009

We studied migration, birth rate and death rate of 59 grizzly bears Ursus arctos on a plateau (N = 29) with extensive forestry activities, and adjacent relatively undeveloped mountains (N = 30) during 1998–2003, to examine population parameters and/or limiting factors that might have contributed to a large difference in grizzly bear density between landscapes. Female bears in our low‐density area (i.e. plateau) were heavier, in better condition, and more often accompanied by cubs than their mountain counterparts. Survival rates were comparable for adult bears but were significantly lower for subadult bears on the plateau. All deaths of bears which lived on the plateau for which cause of death was identified were human‐caused as compared with one of three in the mountains. Plateau bear deaths were highest in fall coinciding with people hunting other species. Density‐dependent factors appeared to be more important to mountain bear demographics, whereas bears on the plateau appeared to be limited by human‐caused bear mortality. Forest harvest did not appear to have negative effects on reproductive parameters of female bears, but associated towns and roads allowed for high human‐caused bear mortality. We did not record female dispersal between landscapes leading us to conclude that dispersal from the mountains is unlikely to offset human‐caused mortality on the plateau.
Nesting Ecology of Greater Sage‐Grouse Centrocercus urophasianus at the Eastern Edge of their Historic Distribution
Authors: Herman‐Brunson Katie M. , Jensen Kent C. , Kaczor Nicholas W. , Swanson Christopher C. , Rumble Mark A. , Klaver Robert W.
Published: October 2009

Greater sage‐grouse Centrocercus urophasianus populations in North Dakota declined approximately 67% between 1965 and 2003, and the species is listed as a Priority Level 1 Species of Special Concern by the North Dakota Game and Fish Department. The habitat and ecology of the species at the eastern edge of its historical range is largely unknown. We investigated nest site selection by greater sage‐grouse and nest survival in North Dakota during 2005 – 2006. Sage‐grouse selected nest sites in sagebrush Artemisia spp. with more total vegetative cover, greater sagebrush density, and greater 1‐m visual obstruction from the nest than at random sites. Height of grass and shrub (sagebrush) at nest sites were shorter than at random sites, because areas where sagebrush was common were sites in low seral condition or dense clay or clay‐pan soils with low productivity. Constant survival estimates of incubated nests were 33% in 2005 and 30% in 2006. Variables that described the resource selection function for nests were not those that modeled nest survival. Nest survival was positively influenced by percentage of shrub (sagebrush) cover and grass height. Daily nest survival decreased substantially when percentage of shrub cover declined below about 9% and when grass heights were less than about 16 cm. Daily nest survival rates decreased with increased daily precipitation.
Treatment of metastatic spinal tumors by percutaneous vertebroplasty versus percutaneous vertebroplasty combined with interstitial implantation of 125I seeds
Authors: Yang Zuozhang , Yang Dakuan , Xie Lin , Sun Yuqing , Huang Yunchao , Sun Hongpu , Liu Pengjie , Wu Zhongxiong
Published: October 2009

Background: As the most frequent bone metastasis, spinal metastases cause severe pain and damage to vertebral bodies such as spinal osteolytic destruction and compression fractures. To avoid the trauma and complications of open surgery, a minimally invasive procedure, percutaneous vertebroplasty (PVP), has recently been developed to treat metastatic spinal tumors.

Purpose: To analyze the treatment outcomes of metastatic spinal tumors by percutaneous vertebroplasty (PVP) alone or PVP combined with interstitial implantation of 125I seeds.

Material and Methods: 80 patients with metastatic spinal tumors were randomized to receive PVP alone (40 cases) or PVP combined with 125I seed implantation (40 cases). Digital subtraction angiography (DSA)-guided vertebroplasty was performed under local anesthesia, and acrylic bone cement was injected into the vertebra through a bone trocar to the center of the lesion, with or without simultaneous interstitial implantation of 125I seeds.

Results: At 6-month follow-up, PVP combined with 125I seed implantation resulted in zero cases with complete relief (CR), 36 with partial relief (PR), four with no changes (NC), and zero with progression of disease (PD), while PVP alone without seed implantation resulted in 0 CR, 31 PR, 7 NC, and 2 PD. While the combined-treatment group and the single-PVP group showed overall clinical benefit rates without significant difference (100% and 95.0%, respectively), their visual analogue pain scales (VAS; 2.26±1.05 and 5.41±0.94, respectively) and Karnofsky performance scores (KPS; 92.5±7.1 and 87.7±7.3, respectively) were significantly different after treatment ( P = 0.028 and P = 0.009, respectively). Patients in both groups had 1-year follow-up, and the mean time to tumor progression (TTP) was 9.0 and 8.9 months, respectively (not significant).

Conclusion: PVP is a minimally invasive procedure with small wounds and minor complications. It is effective in the alleviation of pain in metastatic spinal tumor patients, and its clinical outcomes can be enhanced by the combination of interstitial implantation of 125I seeds.
Maximizing the extent of tumor resection during transsphenoidal surgery for pituitary macroadenomas: can endoscopy replace intraoperative magnetic resonance imaging?
Authors: Theodosopoulos Philip V. , Leach James , Kerr Robert G. , Zimmer Lee A. , Denny Amanda M. , Guthikonda Bharat , Froelich Sebastien , Tew John M.
Published: October 2009

Object

Endoscopic approaches to pituitary tumors have become an effective alternative to traditional microscopic transsphenoidal approaches. Despite a proven potential to decrease unexpected residual tumor, intraoperative MR (iMR) imaging is infrequently used even in the few operating environments in which such technology is available. Its use is prohibitive because of its cost, increased complexity, and longer operative times. The authors assessed the potential of intrasellar endoscopy to replace the need for iMR imaging without sacrificing the maximum extent of resection.

Methods

In this retrospective study, 27 consecutive patients underwent fully endoscopic resection of pituitary macroadenomas. Intrasellar endoscopy was used to determine the presence of residual tumor within the sella turcica and tumor cavity. Intraoperative MR imaging was used to identify rates of unexpected residual tumor and the need for further tumor resection.

Results

Intraoperative estimates of the extent of tumor resection were correct in 23 patients (85%). Of 4 patients with unacceptable tumor residuals, 3 underwent further tumor resection. After iMR imaging, the rate of successful completion of the planned extent of resection increased to 26 patients (96%). Rates of both endocrinopathy reversal and postoperative complications were consistent with previously published results for microscopic and endoscopic resection techniques.

Conclusions

The findings in this study provided quantitative evidence that intrasellar endoscopy has significant promise for maximizing the extent of tumor resection and is a useful adjunct to surgical approaches to pituitary tumors, particularly when iMR imaging is unavailable. A larger prospective study on the extent of resection following endoscopic transsphenoidal surgery would strengthen these findings.
Association of a younger age with an increased risk of angiographic and symptomatic vasospasms following subarachnoid hemorrhage
Authors: Magge Suresh N. , Chen H. Isaac , Ramakrishna Rohan , Cen Liyi , Chen Zhen , Elliott J. Paul , Winn H. Richard , Le Roux Peter D.
Published: October 2009

Object

Vasospasm is a leading cause of morbidity and death following aneurysmal subarachnoid hemorrhage (SAH). It is important to predict which patients are at risk for vasospasm so that interventions can be made. There are several potential risk factors for vasospasm, one of which is age. However, the effect of age on vasospasm, particularly symptomatic vasospasm, remains controversial.

Methods

Three hundred ninety-one patients were retrospectively identified from a prospective observational database of patients with SAH who had been admitted to a single center. Demographic and clinical data were recorded, and cerebral angiograms obtained at admission and between 5 and 10 days later were compared. The relationship between age and angiographic and symptomatic vasospasms was examined using logistic regression techniques.

Results

Mild (86 patients), moderate (69 patients), severe (56 patients), and no angiographic vasospasms (180 patients) were documented by comparing admission and follow-up angiograms in each patient. Symptomatic vasospasm was identified in 69 patients (17.6%). Angiographic vasospasm was more frequent as age decreased. Except in patients < 30 years old, the frequency of symptomatic vasospasm also increased with decreasing age (p = 0.0001). After adjusting for variables known to be associated with vasospasm, an advanced age was associated with a reduced incidence of any angiographic vasospasm (OR 0.96, 95% CI 0.94–0.97), severe angiographic vasospasm (OR 0.96, 95% CI 0.95–0.98), and symptomatic vasospasm (OR 0.98, 95% CI 0.96–0.99).

Conclusions

Results in this study show that a younger age is associated with an increased incidence of angiographic and symptomatic vasospasm.
Greenland ice-sheet volume sensitivity to basal, surface and initial conditions derived from an adjoint model
Authors: Heimbach Patrick , Bugnion Véronique
Published: October 2009

We extend the application of control methods to a comprehensive three-dimensional thermomechanical ice-sheet model, SICOPOLIS (SImulation COde for POLythermal Ice Sheets). Lagrange multipliers, i.e. sensitivities, are computed with an exact, efficient adjoint model that has been generated from SICOPOLIS by rigorous application of automatic differentiation. The case study uses the adjoint model to determine the sensitivity of the total Greenland ice volume to various control variables over a 100 year period. The control space has of the order 1.2 × 106 elements, consisting of spatial fields of basal flow parameters, surface and basal forcings and initial conditions. Reliability of the adjoint model was tested through finite-difference perturbation calculations for various control variables and perturbation regions, ascertaining quantitative inferences of the adjoint model. As well as confirming qualitative aspects of ice-sheet sensitivities (e.g. expected regional variations), we detect regions where model sensitivities are seemingly unexpected or counter-intuitive, albeit ‘real’ in the sense of actual model behavior. An example is inferred regions where sensitivities of ice-sheet volume to basal sliding coefficient are positive, i.e. where a local increase in basal sliding parameter increases the ice-sheet volume. Similarly, positive (generally negative) ice temperature sensitivities in certain parts of the ice sheet are found, the detection of which seems highly unlikely if only conventional perturbation experiments had been used. The object of this paper is largely a proof of concept. Available adjoint-code generation tools now open up a variety of novel model applications, notably with regard to sensitivity and uncertainty analyses and ice-sheet state estimation or data assimilation.
Svalbard surge dynamics derived from geometric changes
Authors: Sund Monica , Eiken Trond , Hagen Jon Ove , Kääb Andreas
Published: October 2009

Geometric changes on a sample of Svalbard glaciers were studied using subtraction of repeat digital terrain models to determine early surge-stage dynamics. Changes in surface features were also analyzed. A number of new surges were found for glaciers not known to have surged previously. The surge development could be followed through three stages, of which the first two had not been previously described in Svalbard. The first two stages are mainly identified from glacier thickness changes and showed little visual evidence. In stage 1, initial surface lowering was found in the upper part of the glacier, followed by a thickening further down-glacier in stage 2. Stage 3 represents the period of well-developed surge dynamics that is usually reported. Some surges ceased at stage 2 as a partial surge and never developed into a fully active surge. These partial surges could be misinterpreted as rapid response to climate change. The results of this study further support previous findings that the majority of Svalbard glaciers are of surge type.
Surge propagation constrained by a persistent subglacial conduit, Bakaninbreen–Paulabreen, Svalbard
Authors: Benn Douglas I. , Kristensen Lene , Gulley Jason D.
Published: October 2009

Glacier surges tend to be initiated in relatively small regions, then propagate down-glacier, up-glacier and/or across-glacier. The processes controlling patterns and rates of surge propagation, however, are incompletely understood. In this paper, we focus on patterns of surge propagation in two confluent glaciers in Svalbard, and examine possible causes. One of these glaciers, Bakaninbreen, surged in 1985–95. The surge propagated ∽7 km down-glacier, but did not cross the medial moraine onto the other glacier, Paulabreen. When Paulabreen surged between 2003 and 2005, the surge wave travelled several km down-glacier, but its lateral boundary stayed very close to the medial moraine. The confluent glaciers formerly extended into a fjord, and bathymetric mapping and historical observations show that an active subglacial conduit has existed between Bakaninbreen and Paulabreen since at least the early 20th century. The existence of a persistent subglacial conduit below the medial moraine was confirmed when we entered and mapped a Nye channel at the confluence of Bakaninbreen and Paulabreen. We argue that the conduit acts as a barrier to surge propagation. If pressurized water below one branch of the glacier system reaches the conduit, water can be readily evacuated, preventing its propagation into the other branch.