bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of moisture regime and tree species composition on nitrogen cycling dynamics in hardwood forests of Mammoth Cave National Park, Kentucky, USA
Authors: Fabio Eric S. , Arthur Mary A. , Rhoades Charles C. 
Published: February 2009

Understanding how natural factors interact across the landscape to influence nitrogen (N) cycling is an important focus in temperate forests because of the great inherent variability in these forests. Site-specific attributes, including local topography, soils, and vegetation, can exert important controls on N processes and retention. Seasonal monitoring of N cycling dynamics was carried out for 2 years in deciduous forest stands that differed in soil moisture status and geologic substrate, and thus, in tree species composition to determine the effects of tree species composition, mediated by moisture and soil chemistry, on N cycling. Geologic substrate influenced soil and soil leachate chemistry but did not appear to affect N cycling in the upper 10 cm. Moisture status was strongly correlated with tree species composition, which was significantly related to N cycling parameters. Sugar maple was associated with high net nitrification rates and soil solution NO3 concentrations, whereas in oak stands nitrification was low and soil solution NO3 was at or near detection limits. Tree species composition in the understory suggests that sugar maple may be increasing in mesic sites and that oak regeneration in all sites is very limited, and a shift in species composition could result in changes to N retention and export.
Canopy tree growth responses following selection harvest in seven species varying in shade tolerance
Authors: Jones Trevor A. , Domke Grant M. , Thomas Sean C. 
Published: February 2009

We used tree ring measurements to investigate the temporal response of basal area increment (BAI) of canopy trees following selection harvests by sampling across a chronosequence of stands with known harvest dates in tolerant hardwood (Great Lakes – St. Lawrence) stands in central Ontario. Seven tree species of various shade tolerances ranged widely in their responses to reduced competition. The more shade-tolerant species responded more positively: shade-tolerant species showed an average increase in BAI of 35% 4–15 years postharvest compared with 16% for mid-tolerant species and –7.5% for intolerant species. All species showed a time-lag in postharvest growth responses, with maximum growth responses occurring between 3 and 15 years postharvest. Tree size was the most important factor determining the magnitude of BAI response, with smaller trees consistently responding more than larger trees. We suggest that higher growth responses to selection harvests among shade-tolerant species may contribute to declines in mid-tolerant species abundance in selection-managed stands. More broadly, interspecific variability in canopy tree responses to forest disturbance appears to follow patterns distinct from seedling and sapling responses, with important implications to forest community dynamics in both managed and unmanaged forests.
Forest floor fuel consumption and carbon emissions in Canadian boreal forest fires
Authors: de Groot W.J. , Pritchard J.M. , Lynham T.J. 
Published: February 2009

In many forest types, over half of the total stand biomass is located in the forest floor. Carbon emissions during wildland fire are directly related to biomass (fuel) consumption. Consumption of forest floor fuel varies widely and is the greatest source of uncertainty in estimating total carbon emissions during fire. We used experimental burn data (59 burns, four fuel types) and wildfire data (69 plots, four fuel types) to develop a model of forest floor fuel consumption and carbon emissions in nonpeatland standing-timber fuel types. The experimental burn and wildfire data sets were analyzed separately and combined by regression to provide fuel consumption models. Model variables differed among fuel types, but preburn fuel load, duff depth, bulk density, and Canadian Forest Fire Weather Index System components at the time of burning were common significant variables. The regression R2 values ranged from 0.206 to 0.980 (P < 0.001). The log–log model for all data combined explained 79.5% of the regression variation and is now being used to estimate annual carbon emissions from wildland fire. Forest floor carbon content at the wildfires ranged from 40.9% to 53.9%, and the carbon emission rate ranged from 0.29 to 2.43 kg·m–2.
Polymorphonuclear blood leukocytes and restenosis after intracoronary implantation of drug-eluting stentsThis article is one of a selection of papers from the NATO Advanced Research Workshop on Translational Knowledge for Heart Health (published in part 1 of a 2-part Special Issue).
Authors: Gabbasov Zufar A. , Kozlov Sergey G. , Lyakishev Anatoly A. , Saburova Olga S. , Smirnov Vladimir A. , Smirnov Vladimir N. 
Published: February 2009

Peripheral blood contents of osteonectin-positive progenitor cells and polymorphonuclear granulocytes were examined by flow cytometry in 38 patients after myocardial revascularisation with drug-eluting stents. Repeat coronary angiography performed 6–12 months after stent implantation revealed in-stent restenosis in 15 patients and its absence in 23 patients. The plasma levels of osteonectin-positive progenitor cells, neutrophils, and basophils did not differ in patients with and without restenosis. Eosinophil blood levels in patients with and without restenosis were 262 ± 68 and 124 ± 67 cells/µL (mean ± SD, p < 0.001), respectively. Only one of 19 patients (5%) with eosinophil content lower than the distribution median for the entire group developed restenosis, whereas in the group with eosinophil contents higher than the median (n = 19) restenosis occurred in 14 patients (74%, p < 0.001). Our findings suggest that the frequency of restenoses after stenting is related to high peripheral blood eosinophil content.
Oxytocin exerts protective effects on in vitro myocardial injury induced by ischemia and reperfusionThis article is one of a selection of papers from the NATO Advanced Research Workshop on Translational Knowledge for Heart Health (published in part 1 of a 2-part Special Issue).
Authors: Ondrejcakova Maria , Ravingerova Tatiana , Bakos Jan , Pancza Dezider , Jezova Daniela 
Published: February 2009

Among the cardiovascular pathologies, ischemic heart disease is a serious medical problem that can result in cardiac injury and (or) heart failure. The aim of the present study was to test the hypothesis that neuropeptide oxytocin induces cardioprotective effects on ischemia–reperfusion-induced myocardial damage. The functional parameters of isolated Langendorff-perfused rat hearts were recorded before and after global 25 min ischemia and subsequent reperfusion. The infarct size was determined by a computerized planimetric method. The results showed that oxytocin produced negative chronotropic effect even at low concentrations (90–125 nmol/L). Perfusion with oxytocin before ischemia resulted in significant reduction of the infarct size (p < 0.01), which was about 66% smaller than that in the control group. To evaluate the functional mechanisms involved, further experiments were performed under conditions of constant heart rate. The lower dose of oxytocin (90 nmol/L), which was ineffective in spontaneously beating hearts, induced a significant decrease of contractility. Elimination of the negative chronotropic effect of oxytocin prevented its cardioprotective action. In conclusion, our results demonstrated an attenuation of the infarct size in oxytocin-treated hearts, indicating a cardioprotective effect of oxytocin. The data suggest that the negative chronotropic action of oxytocin participates in its protective effects on ischemia–reperfusion-induced myocardial injury.
Transient receptor potential: a large family of new channels of which several are involved in cardiac arrhythmiaThis article is one of a selection of papers from the NATO Advanced Research Workshop on Translational Knowledge for Heart Health (published in part 1 of a 2-part Special Issue).
Authors: Vassort Guy , Alvarez Julio 
Published: February 2009

The transient receptor potential (TRP) family of ion channels comprises more than 50 cation-permeable channels expressed throughout the animal kingdom. TRPs can be grouped into 7 main subfamilies according to structural homology: the TRPC (canonical), TRPV (vanilloid), TRPM (melastatin), TRPP (polycystin), TRPML (mucolipin), TRPA (ankyrin), and TRPN (NO mechanopotential). During the past 20 years, the cloning and characterization after reexpression of most members of these cation channels have led to a plethora of data and more recently to some understanding of their roles in various cells and tissues. Specifically in the heart, TRPs are known to be involved in various diseases, including hypertrophy, heart failure, and arrhythmia. The later part of this review focuses on the potential contribution of TRPs to cardiac rhythm and their potential proarrhythmic effects. Furthermore, several neurotransmitters that activate the formation of diacylglycerol could modulate cardiac rhythm or, like ATP, induce arrhythmia.
Nuclear membrane receptors and channels as targets for drug development in cardiovascular diseasesThis article is one of a selection of papers from the NATO Advanced Research Workshop on Translational Knowledge for Heart Health (published in part 1 of a 2-part Special Issue).
Authors: Bkaily Ghassan , Avedanian Levon , Jacques Danielle 
Published: February 2009

The use of confocal microscopy has shown that the nucleus plays an important role in excitation–contraction and excitation–secretion coupling of several excitable and nonexcitable cardiovascular cells. It has shown that the nuclear membranes, like the sarcolemmal membrane, possess ionic transporters as well as G protein-coupled receptors (GPCRs), which play a major role in modulating both cytosolic and nuclear ionic homeostasis and nuclear signalling. During spontaneous contraction of heart cells, the increase in cytosolic Ca2+was immediately followed by a transient increase in nuclear Ca2+. The nuclear Ca2+rise during excitation–contraction and excitation–secretion coupling was both dependent and independent of changes in cytosolic Ca2+. Nuclear membrane GPCRs, such as those of angiotensin II, neuropeptide Y, and ET-1, were functional and contributed to modulation of nuclear ionic homeostasis via direct and (or) indirect modulation of nuclear membrane ionic transporters such as channels, pumps, and exchangers. The signalling of nuclear membrane GPCRs may also contribute to modulation of gene expression, which may regulate proliferation and remodelling of cells and, indeed, life and death. Direct or indirect targeting of nuclear membrane ionic transporters and GPCRs may constitute a new target for drug action.
Isolated Type II Superior Labral Anterior Posterior Lesions
Authors: Neri Brian R. , Vollmer Emily A. , Kvitne Ronald S. 
Published: February 2009

Background Superior labral anterior posterior tears have been described as symptomatic lesions in shoulders of patients of varying ages. It is unknown if age affects clinical outcome of arthroscopic fixation of type II superior labral anterior posterior repairs. Hypothesis Clinical outcome of arthroscopic fixation of isolated type II superior labral anterior posterior tears differs between younger (<40 years) and older (≥40 years) patients. Study Design Cohort study; Level of evidence, 3. Methods Clinical results of arthroscopic fixation of isolated unstable type II superior labral anterior posterior repairs were compared between 25 patients younger than 40 years (group 1) and 25 patients aged 40 years or older (group 2). Patients with concomitant procedures, prior/subsequent shoulder surgeries, and use of non—suture anchor devices were excluded. Outcomes at a minimum 1-year follow-up were assessed using range of motion measurements and the American Shoulder and Elbow Surgeons questionnaire as compared with preoperative data. Ability and time to return to prior level of activity were assessed. Results At a mean 3-year follow-up, there were statistically significant improvements in American Shoulder and Elbow Surgeons scores for both groups (P < .0001) but no significant difference between final American Shoulder and Elbow Surgeons scores (group 1, 91; group 2, 87; P > .198). Both groups demonstrated good or excellent results in >80% of patients. A traumatic mechanism of injury (P = .0346) and presence of osteoarthritis (P = .0401) were independent factors resulting in significantly lower postoperative scores. There were statistically significant differences in preoperative and postoperative range of motion for internal rotation (group 1, P = .0321) and forward elevation (group 2, P = .0003). Return to prior level of activity was similar between younger and older age groups: 80% versus 74%. Time to return to sport was prolonged for group 2 (11.0 months) compared with group 1 (8.45 months). Patients without osteoarthritis were significantly more likely to return to previous levels of activity than were those who had osteoarthritis (P = .0044). Conclusion Good to excellent results and high return to prior level of activity can be expected for the majority of properly indicated patients who undergo isolated type II superior labral anterior posterior repairs, regardless of age. Subtle deficits in range of motion were experienced by both age groups; this did not seem to affect final outcomes. The presence of osteoarthritis was associated with lower American Shoulder and Elbow Surgeons scores and inability to return to prior level of activity. Time to return to activity was prolonged for the older group.
Force in the Achilles Tendon During Walking With Ankle Foot Orthosis
Authors: Fröberg Åsa , Komi Paavo , Ishikawa Masaki , Movin Tomas , Arndt Anton 
Published: February 2009

Background Ankle foot orthoses are used for postoperative treatment of Achilles tendon ruptures and decrease calf muscle electromyography activity during walking. Hypothesis Achilles tendon load decreases with increased restriction of dorsiflexion and is associated with decreased triceps surae activity. Study Design Controlled laboratory study. Methods In 8 subjects, the maximum force and rate of force development in the Achilles tendon were measured with an optic fiber technique, and the activity of the gastrocnemius, soleus, and tibialis anterior muscles was recorded using electromyography. Trial conditions were walking barefoot and wearing an ankle-foot orthoses set in 3 different positions: (1) locked at 20° of plantar flexion and with free plantar flexion but restricted dorsiflexion to (2) 10° plantar flexion and (3) 10° dorsiflexion, respectively. The design of the ankle foot orthoses did not provide heel support when fixed in a plantarflexed position. Results Maximum Achilles tendon force was highest at the ankle-foot orthoses setting of 20° plantar flexion (3.1 times body weight) and decreased to 2.1 times body weight during barefoot walking ( P < .01). The rate of Achilles tendon force showed an increasing trend with less-restricted dorsiflexion. Soleus activity was 52% of mean barefoot walking activity at 3 20° plantar flexion ( P < .001) and then increased as dorsiflexion was less restricted. Conclusion Weightbearing in ankle-foot orthoses when dorsiflexion is restricted beyond neutral may result in increased forces in the Achilles tendon compared with barefoot walking, despite reduced electromyography activity in the triceps surae and decreased rate of force development. Clinical Relevance If patients bear full weight in an ankle-foot orthoses locked at 20° plantar flexion without heel support, the maximum force in the tendon may exceed that encountered during barefoot walking.
Arthroscopic Treatment of Isolated Type II SLAP Lesions
Authors: Boileau Pascal , Parratte Sebastien , Chuinard Christopher , Roussanne Yannick , Shia Derek , Bicknell Ryan 
Published: February 2009

Background Overhead athletes report an inconsistent return to their previous level of sport and satisfaction after arthroscopic SLAP lesion repair. Hypothesis Arthroscopic biceps tenodesis offers a viable alternative to the repair of an isolated type II SLAP lesion. Study Design Cohort study; Level of evidence, 3. Methods Twenty-five consecutive patients operated for an isolated type II SLAP lesion between 2000 and 2004 were evaluated at a mean of 35 months postoperatively (range, 24-69). Patients with associated instability, rotator cuff rupture, posterosuperior impingement, or previous shoulder surgery were excluded. Ten patients (10 men) with an average age of 37 years (range, 19-57) had a SLAP repair performed with suture anchors. Fifteen patients (9 men and 6 women) with an average age of 52 years (range, 28-64) underwent arthroscopic biceps tenodesis performed with an absorbable interference screw. Arthroscopic diagnosis and treatment were performed by a single experienced shoulder surgeon, and all patients were reviewed by an independent examiner. Results In the repair group, the Constant score improved from 65 to 83 points; however, 60% (6 of 10) of the patients were disappointed because of persistent pain or inability to return to their previous level of sports participation. In the tenodesis group, the Constant score improved from 59 to 89 points, and 93% (14/15) were satisfied or very satisfied. Thirteen patients (87%) were able to return to their previous level of sports participation following biceps tenodesis, compared with only 20% (2 of 10) after SLAP repair (P = .01). Four patients with failed SLAP repairs underwent subsequent biceps tenodesis, resulting in a successful outcome and a full return to their previous level of sports activity. Conclusion Arthroscopic biceps tenodesis can be considered an effective alternative to the repair of a type II SLAP lesion, allowing patients to return to a presurgical level of activity and sports participation. The results of biceps reinsertion are disappointing compared with biceps tenodesis. Furthermore, biceps tenodesis may provide a viable alternative for the salvage of a failed SLAP repair. As the age of the 2 treatment groups differed, these findings should be confirmed by future studies.
Patient Perceptions on the Use of Advance Directives and Life Prolonging Technology
Authors: Clements John M. 
Published: February 2009

Introduction: Use of advance directives is underutilized despite the Patient Self Determination Act of 1990. This study was undertaken to determine use and opinions of advance directives by patients at a multidisciplinary. Methods: Institutional Review Board—approved prospective survey of patients age 18 and over. Results: Of 306 participants, 77 (25.2%) had a durable power of attorney and 45 (14.7%) had living wills. Of these, 226 (73.9%) responded that it was important to make health care wishes known to their doctor. Only 36 (15.9%) had done so. A total of 266 (86.9%) felt it was important to discuss health care wishes with their family and only 160 (60.1%) had done so. Conclusions: While adequately describing use and attitudes toward advance directives, it is significant to note that patients believe their wishes for end-of-life care will be honored; however, they fail to take the necessary steps to guarantee this.
Nf1 haploinsufficiency and Icsbp deficiency synergize in the development of leukemias
Authors: Koenigsmann Jessica , Rudolph Cornelia , Sander Sandrine , Kershaw Olivia , Gruber Achim D. , Bullinger Lars , Schlegelberger Brigitte , Carstanjen Dirk 
Published: February 2009

AbstractLoss of neurofibromin or interferon consensus sequence binding protein (Icsbp) leads to a myeloproliferative disorder. Transcription of NF1 is directly controlled by ICSBP. It has been postulated that loss of NF1 expression resulting from loss of transcriptional activation by ICSBP contributes to human hematologic malignancies. To investigate the functional cooperation of these 2 proteins, we have established Icsbp-deficient mice with Nf1 haploinsufficiency. We here demonstrate that loss of Icsbp and Nf1 haploinsufficiency synergize to induce a forced myeloproliferation in Icsbp-deficient mice because of an expansion of a mature myeloid progenitor cell. Furthermore, Nf1 haploinsufficiency and loss of Icsbp contribute synergistically to progression of the myeloproliferative disorder toward transplantable leukemias. Leukemias are characterized by distinct phenotypes, which correlate with progressive genetic abnormalities. Loss of Nf1 heterozygosity is not mandatory for disease progression, but its occurrence with other genetic abnormalities indicates progressive genetic alterations in a defined subset of leukemias. These data show that loss of the 2 tumor suppressor genes Nf1 and Icsbp synergize in the induction of leukemias.
Inverse Langmuir method for oligonucleotide microarray analysis
Authors: Mulders Geert CWM , Barkema Gerard T , Carlon Enrico 
Published: February 2009

Abstract

Background
An algorithm for the analysis of Affymetrix Genechips is presented. This algorithm, referred to as the Inverse Langmuir Method (ILM), estimates the binding of transcripts to complementary probes using DNA/RNA hybridization free energies, and the hybridization between partially complementary transcripts in solution using RNA/RNA free energies. The balance between these two competing reactions allows for the translation of background-subtracted intensities into transcript concentrations.

Results
To validate the ILM, it is applied to publicly available microarray data from a multi-lab comparison study. Here, microarray experiments are performed on samples which deviate only in few genes. The log2 fold change between these two samples, as obtained from RT-PCR experiments, agrees well with the log2 fold change as obtained with the ILM, indicating that the ILM determines changes in the expression level accurately. We also show that the ILM allows for the identification of outlying probes, as it yields independent concentration estimates per probe.

Conclusion
The ILM is robust and offers an interesting alternative to purely statistical algorithms for microarray data analysis.