bluuebunny/crossref_metadata_2025_split huggingface dataset:
How small is too small? Incubation of large eggs by a small host
Authors: Stewart Rebecca L.M. , Guigueno Mélanie F. , Sealy Spencer G. 
Published: October 2011

The Yellow Warbler ( Setophaga petechia (L., 1766)) is among the putative hosts of the Black-billed Cuckoo ( Coccyzus erythropthalmus (Wilson, 1811)), which is hypothesized to have once been an obligate brood parasite. Most parasites lay a small egg relative to their body size, possibly to prevent hosts from discriminating against the larger egg and to facilitate incubation. We tested whether warblers, which lay eggs ~17% of the volume of cuckoo eggs, could have potentially been suitable hosts of Coccyzus cuckoos by determining whether they accept and successfully incubate cuckoo-sized eggs. Warblers accepted 63% (n = 54) of cuckoo-sized eggs added into their nests and successfully incubated eggs as large as cuckoo eggs (surrogate American Robin ( Turdus migratorius L., 1766) eggs). This suggests that the lower limit to host size is not just related to egg size. Warblers are not ideal hosts because they rejected a high frequency of experimental eggs (37%). Nests from which eggs were rejected tended to have smaller volumes than nests at which eggs were accepted. The nest cups of warblers are oval, which may promote egg crowding more than round cups. Factors such as nest size, not host size, influence acceptance or rejection of large eggs by Yellow Warblers.
Changes in relative abundance of snowshoe hares (Lepus americanus) across a 265-year gradient of boreal forest succession
Authors: Hodson James , Fortin Daniel , Bélanger Louis 
Published: October 2011

Understory regeneration within canopy gaps in old-growth boreal forests may provide suitable habitat for wildlife typically associated with early-seral stages, leading to an increase in their abundance in late succession. We surveyed a chronosequence of postfire (17–265 years) and postharvest (3–63 years) stands in Canada’s eastern boreal forest to determine whether snowshoe hares ( Lepus americanus Erxleben, 1777) followed a bimodal abundance distribution with stand age that reflects changes in food and cover during postdisturbance succession. A strong peak in relative hare abundance occurred during the first 80 years of succession, with highest faecal pellet densities observed between 40 and 50 years after disturbance. Changes in hare abundance during this period were similar among fire- and clearcut-origin stands and closely tracked changes in lateral cover and vertical cover. Pellet density increased again in stands >180 years. Variation in hare abundance during late succession was partially mediated by gap dynamics, with highest pellet densities in stands occupied by an intermediate proportion of mortality-origin canopy gaps. Hares thus undergo rapid changes in abundance during early succession followed by a much longer period of subtle changes in density as stands develop old-growth structure. Shifting forest age-class distribution induced by forest management could therefore significantly alter regional spatiotemporal dynamics of snowshoe hares.
Encouraging participation in virtual communities through usability and sociability development
Authors: Lu Xianghua , Phang Chee Wei , Yu Jie 
Published: October 2011

Usability and sociability are two characteristics of a virtual community that are critical to its success. This study aims to explore how usability and sociability of virtual communities can be developed in order to encourage members' continuous participation in these communities. A theoretical model is proposed to explain the effects of factors related to usability and sociability on members' continuous participation through the motivational beliefs of perceived usefulness, perceived enjoyment and sense of belonging. Data was collected from members of five popular leisure-oriented virtual communities in China. The results show that both perceived enjoyment and sense of belonging impact members' continuous participation intention.
Among the usability-and sociability-related factors, we find that information service quality is the most critical factor that encourages members to continuously participate in virtual communities, while interaction support quality, incentive policy, and event organization also have positive effects on members' continuous participation intention via perceived enjoyment and sense of belonging. Surprisingly, leaders' involvement has no impact on members' continuous participation. Implications of the study's findings for both research and practice are discussed.
Examining Stools for Colon Cancer Prevention: What Are We Really Looking for?
Authors: Byers Tim 
Published: October 2011

Abstract
Fecal immunochemical testing (FIT) is superior to guiac-based testing if we are looking for blood in stools, as it has better one-time colorectal cancer sensitivity and specificity and better patient acceptance. In this issue of the journal, Cai and colleagues (beginning on page 1572) and Khalid-de Bakker and colleagues (beginning on page 1563) present new information about the one-time test performance of FIT. FIT will have a growing appeal to providers and health care systems as resources for clinical preventive services shrink and as incentives to expand colorectal screening rates increase, but there are good reasons to be cautious about the temptation to organize new FIT screening programs. Colorectal screening has two potential objectives: To find cancers in an earlier, more-treatable stage and to find and remove adenomas to prevent cancers from forming in the first place. Because most adenomas, even advanced adenomas, do not bleed, tests designed to identify occult blood in the stool are better for detecting colorectal cancer, whereas direct endoscopic visualization of the colorectum is better for prevention. Even if advanced adenomas did commonly bleed, low compliance with repeat annual testing will seriously erode the benefit of FIT. Cancer Prev Res; 4(10); 1531–3. ©2011 AACR.
Induction of Vascular GTP-Cyclohydrolase I and Endogenous Tetrahydrobiopterin Synthesis Protect Against Inflammation-Induced Endothelial Dysfunction in Human Atherosclerosis
Authors: Antoniades Charalambos , Cunnington Colin , Antonopoulos Alexis , Neville Matt , Margaritis Marios , Demosthenous Michael , Bendall Jennifer , Hale Ashley , Cerrato Ruha , Tousoulis Dimitris , Bakogiannis Constantinos , Marinou Kyriakoula , Toutouza Marina , Vlachopoulos Charalambos , Leeson Paul , Stefanadis Christodoulos , Karpe Fredrik , Channon Keith M. 
Published: October 2011

Background—
The endothelial nitric oxide synthase cofactor tetrahydrobiopterin (BH4) is essential for maintenance of enzymatic function. We hypothesized that induction of BH4 synthesis might be an endothelial defense mechanism against inflammation in vascular disease states.

Methods and Results—

In Study 1, 20 healthy individuals were randomized to receive
Salmonella typhi
vaccine (a model of acute inflammation) or placebo in a double-blind study. Vaccination increased circulating BH4 and interleukin 6 and induced endothelial dysfunction (as evaluated by brachial artery flow-mediated dilation) after 8 hours. In Study 2, a functional haplotype (X haplotype) in the
GCH1
gene, encoding GTP-cyclohydrolase I, the rate-limiting enzyme in biopterin biosynthesis, was associated with endothelial dysfunction in the presence of high-sensitivity C-reactive protein in 440 coronary artery disease patients. In Study 3, 10 patients with coronary artery disease homozygotes for the
GCH1
X haplotype (XX) and 40 without the haplotype (OO) underwent
S Typhi
vaccination. XX patients were unable to increase plasma BH4 and had a greater reduction of flow-mediated dilation than OO patients. In Study 4, vessel segments from 19 patients undergoing coronary bypass surgery were incubated with or without cytokines (interleukin-6/tumor necrosis factor-α/lipopolysaccharide) for 24 hours. Cytokine stimulation upregulated
GCH1
expression, increased vascular BH4, and improved vasorelaxation in response to acetylcholine, which was inhibited by the GTP-cyclohydrolase inhibitor 2,4-diamino-6-hydroxypyrimidine.

Conclusions—

The ability to increase vascular
GCH1
expression and BH4 synthesis in response to inflammation preserves endothelial function in inflammatory states. These novel findings identify BH4 as a vascular defense mechanism against inflammation-induced endothelial dysfunction.
Tyrosine phosphorylated c-Cbl regulates platelet functional responses mediated by outside-in signaling
Authors: Buitrago Lorena , Langdon Wallace Y. , Sanjay Archana , Kunapuli Satya P. 
Published: October 2011

Abstractc-Cbl protein functions as an E3 ligase and scaffolding protein, where 3 residues, Y700, Y731, and Y774, upon phosphorylation, have been shown to initiate several signaling cascades. In this study, we investigated the role of these phospho-tyrosine residues in the platelet functional responses after integrin engagement. We observed that c-Cbl Y700, Y731 and Y774 undergo phosphorylation upon platelet adhesion to immobilized fibrinogen, which was inhibited in the presence of PP2, a pan-src family kinase (SFK) inhibitor, suggesting that c-Cbl is phosphorylated downstream of SFKs. However, OXSI-2, a Syk inhibitor, significantly reduced c-Cbl phosphorylation at residues Y774 and Y700, without affecting Y731 phosphorylation. Interestingly, PP2 inhibited both platelet-spreading on fibrinogen as well as clot retraction, whereas OXSI-2 blocked only platelet-spreading, suggesting a differential role of these tyrosine residues. The physiologic role of c-Cbl and Y731 was studied using platelets from c-Cbl KO and c-CblYF/YF knock-in mice. c-Cbl KO and c-CblYF/YF platelets had a significantly reduced spreading over immobilized fibrinogen. Furthermore, clot retraction with c-Cbl KO and c-CblYF/YF platelets was drastically delayed. These results indicate that c-Cbl and particularly its phosphorylated residue Y731 plays an important role in platelet outside-in signaling contributing to platelet-spreading and clot retraction.
Stereotactic Brachytherapy With Iodine-125 Seeds for the Treatment of Inoperable Low-Grade Gliomas in Children: Long-Term Outcome
Authors: Ruge Maximilian I. , Simon Thorsten , Suchorska Bogdana , Lehrke Ralph , Hamisch Christina , Koerber Friederike , Maarouf Mohammad , Treuer Harald , Berthold Frank , Sturm Volker , Voges Jürgen 
Published: October 2011

Purpose Resection is generally considered the gold standard for treatment of low-grade (WHO grades I and II) gliomas (LGGs) in childhood. However, approximately 30% to 50% of these tumors are inoperable because of their localization in highly eloquent brain areas. A few reports have suggested stereotactic brachytherapy (SBT) with implantation of iodine-125 (125I) seeds as a safe and effective local treatment alternative. This single-center study provides a summary of the long-term outcome after SBT in one of the largest reported patient series. Patients and Methods All pediatric patients treated with SBT (125I seeds; cumulative therapeutic dose 50-65 Gy within 9 months) by our group for LGG with follow-up of more than 6 months were included. Clinical and radiologic outcome, time to progression, and overall survival were evaluated. Prognostic factors (age, sex, Karnofsky performance score, tumor volume, and histology) for survival and disease progression were investigated. Results In all, 147 of 160 pediatric patients treated with SBT (from 1982 through 2009) were analyzed in detail. Procedure-related mortality was zero, and the 30-day morbidity was transient and low (5.4%). Survival rates at 5 and 10 years were 93%, and 82%, respectively, with no significant difference between WHO grades I and II tumors (median follow-up, 67.1 ± 57.7 months). Twenty-one (14.8%) of 147 patients presented with tumor relapse. The remaining 126 patients revealed complete response in 24.6%, partial response in 31.0%, and stable disease in 29.6%. Neurologic status improved (57.8%) or remained stable (23.0%). None of the evaluated factors had significant impact on the study's end points except tumor volume more than 15 mL, which caused significantly higher rates of tumor recurrence (P < .05). Conclusion We demonstrate that SBT represents a safe, minimally invasive, and highly effective local treatment option for pediatric patients with inoperable LGG WHO grades I and II.
Plasma Platelet-Activating Factor–Acetyl Hydrolase Activity and the Levels of Free Forms of Biomarker of Lipid Peroxidation in Cerebrospinal Fluid of Patients With Aneurysmal Subarachnoid Hemorrhage
Authors: Hirashima Yutaka , Doshi Masaru , Hayashi Nakamasa , Endo Shunro , Akazawa Yoko , Shichiri Mototada , Yoshida Yasukazu 
Published: October 2011

AbstractBackground:Free radicals and lipid peroxidation are thought to be related to the vasospasm generation after subarachnoid hemorrhage (SAH). Plasma platelet-activating factor-acetyl hydrolase (PAF-AH) degrades phospholipids with an oxidatively modified fatty acyl chain.Objective:To compare plasma PAF-AH activity and free forms of biomarker of lipid peroxidation in cerebrospinal fluid (CSF) between patients with and without symptomatic vasospasm (SVS) after SAH.Methods:The identification of PAF-AH in CSF was performed by Western blotting. The genotype at position 279 of the plasma PAF-AH gene was determined. The activities of PAF-AH and the levels of free 8-iso-prostaglandin F2α (free isoPs), free hydroxyoctadecadienoic acid (free HODE), and free hydroxyeicosatetraenoic acid (free HETE) in CSF were measured.Results:The PAF-AH in CSF was confirmed to be only the plasma type. The genotype of the plasma PAF-AH was not different between patients with and without SVS. Free isoPs, free HODE, and free HETE showed higher values in patients without SVS in 0 to 4 days and 5 to 9 days after SAH. The PAF-AH activity also was higher in patients without SVS in 0 to 4 days and 5 to 9 days after SAH. The associations between PAF-AH activity and free isoPs, and between PAF-AH activity and free HODE were significant.Conclusion:Oxidized lipids of lipoproteins and blood cell membranes produced by reactive oxygen species in CSF when SAH occurs may be the main source of lipid peroxidation. Plasma PAF-AH can hydrolyze oxidized phospholipids, and may attenuate the spreading of lipid peroxidation and participate in defense mechanisms against vasospasm after SAH.
Anatomical Study on the “Perforator-free Zone”: Reconsidering the Proximal Superior Cerebellar Artery and Basilar Artery Perforators
Authors: Garcia-Gonzalez Ulises , Cavalcanti Daniel D. , Agrawal Abhishek , Spetzler Robert F. , Preul Mark C. 
Published: October 2011

Abstract

Background:
The proximal superior cerebellar artery (pSCA) is often considered a perforator-free area. Precise anatomical knowledge of this region clarifies the pathophysiology underlying posterior fossa ischemic syndromes and helps avoid treatment-related complications.

Objective:
To anatomically evaluate perforating branches arising from the pSCA and the upper basilar artery (BA).

Methods:
Forty-four SCAs from 20 cadaveric heads were examined to determine patterns of the pSCA; its morphometry for medial and lateral branches; and frequency, number, diameter, distribution, and vascular territory of perforators arising from the pSCA and rostral BA.

Results:
SCA arose as a single trunk in 36 sides (90%): mean diameter at origin was 1.38 mm; mean length was 14.± 6 7.9 mm. Ninety-nine pSCA perforator branches were present in 82% of specimens (mean, 2.3 ± 1.6; range, 0-7 perforators/side). Of these, 59% were direct, belonging to the interpeduncular group in 85% of cases; 28% were short circumflex, belonging to lateral and medial pontine group; and 13% were long circumflex, reaching the medullary perforation zone (basal cerebellar group). Median distance to the first perforator was 2.0 mm (range, 0.1–15 mm). There were 132 perforator branches in the last centimeter of the BA.

Conclusion:
The pSCA should not be regarded as a perforator-free area. Although the pSCA territories likely overlap with the posterior cerebral artery, BA, and anterior inferior cerebellar artery, the pSCA segment cannot be surgically manipulated with impunity.
Comparison of FDG-PET/CT and bone scintigraphy for detection of bone metastases in breast cancer
Authors: Hahn Steffen , Heusner Till , Kümmel Sherko , Köninger Angelika , Nagarajah James , Müller Stefan , Boy Christian , Forsting Michael , Bockisch Andreas , Antoch Gerald , Stahl Alexander 
Published: October 2011

Background Bone scintigraphy is the standard procedure for the detection of bone metastases in breast cancer patients. FDG-PET/CT has been reported to be a sensitive tool for tumor staging in different malignant diseases. However, its accuracy for the detection of bone metastases has not been compared to bone scintigraphy. Purpose To compare whole-body FDG-PET/CT and bone scintigraphy for the detection of bone metastases on a lesion basis in breast cancer patients. Material and Methods Twenty-nine consecutive women (mean age 58 years, range 35-78 years) with histologically proven breast cancer were assessed with bone scintigraphy and whole-body FDG-PET/CT. Twenty-one patients (72%) were suffering from primary breast cancer and eight patients (28%) were in aftercare with a history of advanced breast cancer. Both imaging procedures were assessed for bone metastases by a radiologist and a nuclear medicine physician. Concordant readings between bone scintigraphy and FDG-PET/CT were taken as true. Discordant readings were verified with additional MRI imaging in all patients and follow-up studies in most patients. Results A total of 132 lesions were detected on bone scintigraphy, FDG-PET/CT or both. According to the reference standard, 70/132 lesions (53%) were bone metastases, 59/132 lesions (45%) were benign, and three lesions (2%) remained unclear. The sensitivity of bone scintigraphy was 76% (53/70) compared to 96% (67/70) for FDG-PET/CT. The specificity of bone scintigraphy and FDG-PET/CT was 95% (56/59) and 92% (54/59), respectively. According to the reference standard bone metastases were present in eight out of the 29 patients (28%), whereas 20 patients (69%) were free of bone metastases. One (3%) patient had inconclusive readings on both modalities as well as on MRI and follow-up studies. Bone scintigraphy and FDG-PET/CT correctly identified seven out of eight patients with bone metastases and 20 out of 20 patients free of metastases. Conclusion On a lesion-basis whole-body FDG-PET/CT is more sensitive and equally specific for the detection of bone metastases compared with bone scintigraphy.
Classification of persistent primitive trigeminal artery (PPTA): a reconsideration based on MRA
Authors: Weon Young Cheol , Choi Seong Hoon , Hwang Jae Cheol , Shin Shang Hun , Kwon Woon-Jung , Kang Byeong Seong 
Published: October 2011

Background Persistent primitive trigeminal artery (PPTA) is the most common permanent carotid-basilar anastomosis. Magnetic resonance angiography (MRA) has become the primary non-invasive imaging technique for evaluation of cerebral vascular anatomy and can provide detailed 3D imaging of intracranial vessels. Purpose To evaluate the usefulness of MRA for the detection of PPTA and to re-classify its variations based on the embryologic types of PcomA and its relationship with the basilar artery and its branches. Material and Methods Of the total 7329 patients who underwent MRA at our institution from March 2008 through November 2010, we retrospectively analyzed the MRAs of 24 patients with a PPTA. Special attention was given to defining the relationship of the PPTA and the basilar artery with PcomA and to determine the site of origin, size, and course of the PPTA. The PPTA classification included five types based on their anatomic relationship to the neighboring arteries. Clinical features and associated vascular anomalies are also described. Results Twenty-four (17 women and seven men, 34 ~ 81 years of age, mean age 59.67 years) of the 7329 patients had a PPTA (0.33 %). Eleven cases (45.8%) were classified as type 1, three (12.5%) as type 2, five (20.8%) as type 3, one (4.2%) as type 4, and four (16.7%) as type 5b. Fifteen PPTAs (62.5%) were located on the left side and nine were located (37.5%) on the right side. The basilar artery proximal to the insertion of the PPTA showed severe to moderate hypoplasia in 13 cases (54%). Nine intracranial artery aneurysms were detected in seven (29%) of the 24 study patients. Conclusion This study revealed five types of PPTA and necessitates an adjustment of the previous classification of PPTA on the basis of our MRA examinations. A PPTA should be considered by both the clinician and the radiologist who interpret MR angiography.
Effect of growth hormone and melatonin on the brain: from molecular mechanisms to structural changes
Authors: Kireev Roman A. , Cuesta Sara , Vara Elena , Tresguerres Jesus A.F. 
Published: October 2011

AbstractAging of the brain causes important reductions in quality of life and has wide socio-economic consequences. An increase in oxidative stress, and the associated inflammation and apoptosis, could be responsible for the pathogenesis of aging associated brain lesions. Melatonin has neuroprotective effects, by limiting the negative effects of oxygen and nitrogen free radicals. Growth hormone (GH) might exert additional neuro-protective and or neurogenic effects on the brain. The molecular mechanisms of the protective effects of GH and melatonin on the aging brain have been investigated in young and old Wistar rats. A reduction in the total number of neurons in the hilus of the dentate gyrus was evident at 24 months of age and was associated with a significant increase in inflammation markers as well as in pro-apoptotic parameters, confirming the role of apoptosis in its reduction. Melatonin treatment was able to enhance neurogenesis in old rats without modification of the total number of neurons, whereas GH treatment increased the total number of neurons without enhancing neurogenesis. Both GH and melatonin were able to reduce inflammation and apoptosis in the hippocampus. In conclusion, neuroprotective effects demonstrated by GH and melatonin in the hippocampus were exerted by decreasing inflammation and apoptosis.
Influence of Birth Weight on Internalizing Traits Modulated by Serotonergic Genes
Authors: Broekman Birit F. P. , Chan Yiong Huak , Goh Liang , Fung Daniel , Gluckman Peter D. , Saw Seang Mei , Meaney Michael J. 
Published: October 2011

OBJECTIVE:Fetal growth predicts childhood behavioral problems associated with brain serotonergic systems. We hypothesized that allelic variations in genes involved in serotonergic function would moderate associations between birth weight (BW) and internalizing traits in childhood.METHODS:The Child Behavior Checklist was administered to 545 healthy Singaporean children at 8 to 12 years. BW, corrected for gestational age, and candidate single-nucleotide polymorphisms (SNPs) in the TPH2, HTR2A, and SCL6A4 genes were investigated.RESULTS:There was no significant main effect of BW on internalizing T scores (F = 1.08; P = .36). After multiple corrections, significant main effects on internalizing T scores were found for HTR2A rs2296972 (adjusted: F = 2.85; P = .019) and HTR2A rs6313 (adjusted: F = 5.91; P = .0002). Significant interactions were found between BW and SNPs for the TPH2 gene (rs2171363: P = .008; rs7305115: P = .007) and the HTR2A gene (rs2770304: P = .001; rs6313: P = .026) for internalizing T scores. The CC genotype of TPH2 rs2171363, GG genotype of TPH2 rs7305115, CC genotype of HTR2A rs2770304, and CC genotype of HTR2A rs6313 were associated with reduced internalizing scores for children born in the quartile above the midpoint. No significant main effects or interactions were found for SCL6A4 SNPs.CONCLUSIONS:These findings suggest that sequence variations in genes involved in serotonergic functions modulate relationships between BW and internalizing traits and might be candidates for plasticity mechanisms that determine individual differences in responses to environmental influences over the course of development.