bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effect of staining on the monotonic tensile mechanical properties of human cortical bone
Authors: Kayacan Ramazan 
Published: September 2007

AbstractMicrodamage in the form of microcracks has been observed in cortical bone following in vivo and in vitro fatigue loading. It has been suggested that bone has an inherent ability to repair microdamage at physiological activity levels. If the biological remodelling and repair process cannot keep up with the rate of damage accumulation, as in ageing bone and in individuals such as athletes and military recruits, microdamage may accumulate even at physiological activity levels. Such microdamage accumulation is thought to contribute to stress and fragility fractures. It is therefore important to obtain quantitative data on the rate of damage accumulation so as to understand the etiology of skeletal fractures. Sequential labelling of microdamage using fluorochrome stains at different stages of mechanical loading is becoming standard for assessing damage evolution. Although verification of this staining technique is provided in the literature, it has not yet been reported if the stains change the mechanical properties of cortical bone. In this study, monotonic tensile tests were performed to investigate the effect of the staining on the monotonic tensile mechanical properties of cortical bone. Forty‐eight specimens were machined from human femora obtained from three male subjects, aged 52–55 years, and all 48 specimens were systematically divided into one control and three treatment groups. Specimens in the first (n = 12) and second treatment groups (n = 12) were stained with alizarin complexone and calcein (0.0005 m), respectively, for 16 h under 50 mmHg vacuum. Specimens in the third treatment group (n = 12) were kept in calcium‐supplemented saline solution under the same conditions of the first and second treatment groups. Specimens in the control group (n = 12) were removed from the freezer prior to testing and allowed to thaw at room temperature in saline solution. Differences among the mean values of the mechanical properties for four testing groups were determined by the Mann–Whitney test at a significance level of P < 0.05. The statistical results indicated that the chelating stains and the staining conditions have no significant effect on the mechanical properties of the cortical bone under monotonic tensile loading. This study demonstrated that microcrack labelling with the chelating stains under aforementioned conditions (stain concentration, staining time, etc.) is a reliable method in that staining cortical bone with alizarin complexone and calcein prior to testing does not affect tensile properties.
Influence of cardiac‐specific overexpression of insulin‐like growth factor 1 on lifespan and aging‐associated changes in cardiac intracellular Ca2+ homeostasis, protein damage and apoptotic protein expression
Authors: Li Qun , Ren Jun 
Published: September 2007

SummaryA fall in circulating levels of cardiac survival factor insulin‐like growth factor 1 (IGF‐1) contributes to cardiac aging. To better understand the role of IGF‐1 in cardiac aging, we examined the influence of cardiac IGF‐1 overexpression on lifespan, cardiomyocyte intracellular Ca2+ homeostasis, protein damage, apoptosis and expression of pro‐ and anti‐apoptotic proteins in young and old mice. Mouse survival rate was constructed by the Kaplan–Meier curve. Intracellular Ca2+ was evaluated by fura‐2 fluorescence. Protein damage was determined by protein carbonyl formation. Apoptosis was assessed by caspase‐8 expression, caspase‐3 and TUNEL (terminal deoxynucleotidyl transferase‐mediated dUTP nick‐end labeling) assay. Pro‐ and anti‐apoptotic proteins including Bax, p53, pp53, Bcl2, Omi/HtrA2, apoptosis repressor with caspase recruitment domain (ARC) and X‐linked inhibitor of apoptosis protein (XIAP) were assessed by Western blot. Aging decreased plasma in IGF‐1 levels, elevated myocyte resting intracellular Ca2+ levels, reduced electrically stimulated rise in intracellular Ca2+ and delayed intracellular Ca2+ decay associated with enhanced protein carbonyl formation, caspase‐8 expression and caspase‐3 activity in FVB mice, all of which with the exception of elevated resting intracellular Ca2+ were attenuated by IGF‐1. Aging up‐regulated expression of Bax, Bcl2 and ARC, down‐regulated XIAP expression and did not affect p53, pp53 and Omi/HtrA2. The IGF‐1 transgene attenuated or nullified aging‐induced changes in Bax, Bcl2 and XIAP. Our data suggest a beneficial role for IGF‐1 in aging‐induced survival, cardiac intracellular Ca2+ homeostasis, protein damage and apoptosis possibly related to pro‐ and anti‐apoptotic proteins.
Chronic calorie restriction increases susceptibility of laboratory mice (Mus musculus) to a primary intestinal parasite infection
Authors: Kristan Deborah M. 
Published: September 2007

SummaryLong‐term calorie restriction (CR) has numerous benefits; however, effects of CR on susceptibility to intact pathogens are not well understood. Because CR enhances immune function of laboratory mice (Mus musculus), it was hypothesized that mice subjected to CR would be less susceptible to experimental infections of the intestinal parasite Heligmosomoides bakeri. Furthermore, because H. bakeri must combat a greater host immune response by CR mice compared to fully fed mice, it also was also hypothesized that (i) worms living in CR hosts would have lower reproduction than worms from ad libitum‐fed mice, and (ii) CR mice would have a more female‐biased sex ratio as male worms may be more vulnerable to host immune response than female worms. Mice were subjected to CR for 6.7 months and were then infected with H. bakeri for one additional month. As expected, CR mice had equal or enhanced immune response (eosinophils and immunoglobin G1 production) to H. bakeri infection compared to ad libitum‐fed mice, and CR mice harbored a more female‐biased sex ratio than ad libitum‐fed mice. Contrary to predictions, CR mice had more worms than ad libitum‐fed mice and the worms from CR mice produced more eggs than worms from ad libitum‐fed mice. These data indicate that, despite the evidence that long‐term CR enhances traditional measures of immune function, CR may actually increase susceptibility to intact parasite infection. Furthermore, changes in worm reproduction and differential survival of male vs. female worms may influence host–parasite transmission dynamics during long‐term host CR.
Mitochondrial gene expression and increased oxidative metabolism: role in increased lifespan of fat‐specific insulin receptor knock‐out mice
Authors: Katic Masa , Kennedy Adam R. , Leykin Igor , Norris Andrew , McGettrick Aileen , Gesta Stephane , Russell Steven J. , Bluher Matthias , Maratos‐Flier Eleftheria , Kahn C. Ronald 
Published: September 2007

SummaryCaloric restriction, leanness and decreased activity of insulin/insulin‐like growth factor 1 (IGF‐1) receptor signaling are associated with increased longevity in a wide range of organisms from Caenorhabditis elegans to humans. Fat‐specific insulin receptor knock‐out (FIRKO) mice represent an interesting dichotomy, with leanness and increased lifespan, despite normal or increased food intake. To determine the mechanisms by which a lack of insulin signaling in adipose tissue might exert this effect, we performed physiological and gene expression studies in FIRKO and control mice as they aged. At the whole body level, FIRKO mice demonstrated an increase in basal metabolic rate and respiratory exchange ratio. Analysis of gene expression in white adipose tissue (WAT) of FIRKO mice from 6 to 36 months of age revealed persistently high expression of the nuclear‐encoded mitochondrial genes involved in glycolysis, tricarboxylic acid cycle, β‐oxidation and oxidative phosphorylation as compared to expression of the same genes in WAT from controls that showed a tendency to decline in expression with age. These changes in gene expression were correlated with increased cytochrome c and cytochrome c oxidase subunit IV at the protein level, increased citrate synthase activity, increased expression of peroxisome proliferator‐activated receptor γ coactivator 1α (PGC‐1α) and PGC‐1β, and an increase in mitochondrial DNA in WAT of FIRKO mice. Together, these data suggest that maintenance of mitochondrial activity and metabolic rates in adipose tissue may be important contributors to the increased lifespan of the FIRKO mouse.
Cerebrospinal Fluid Pressure and Venous Pressure in “Dynamite Headache” and Cluster Headache Attacks
Authors: Hannerz Jan , Greitz Dan 
Published: September 2007

SYNOPSISSix patients with episodic cluster headache were investigated as to blood pressure, heart rate, cerebrospinal fluid pressure (Pcsf) and frontal vein pressure (Pvf) during five nitroglycerin (NG) provoked attacks and one spontaneous attack. In a seventh studied patient the NG failed to provoke an attack. The earlier reported decrease of systolic blood pressure and increase of diastolic blood pressure and heart rate after NG administration were also found in these patients. The “dynamite headache” was related to the start and duration of an increase of the cerebrospinal fluid pressure. There was no relationship between the start or the maximum pain of the cluster headache attack and changes in Pcsf or Pvf. On breathing oxygen during a cluster headache attack, there was a decrease of Pcsf but in some patients a temporary increase of Pvf was observed, which possibly indicates that oxygen simultaneously attains constriction of arteries and veins.
Psychophysiological Response Patterns of Migraine Patients in Two Habituation Tests
Authors: Huber Dorothea , Henrich Gerhard , Gündel Harald 
Published: September 2007

Objective.—To investigate the habituation response pattern of patients with migraine to a simple standard stressor and to a more complex performance‐dependent (achievement) stressor in three peripheral systems (electrodermal, vasomotor, and cardiovascular). We hypothesized that the migraine patients would show abnormal habituation in these peripheral systems, especially in response to achievement stimuli.Background.—Abnormal central habituation to repetitive stimuli has been reported frequently in patients with migraine. But little is known about habituation of the peripheral autonomic nervous system to stressors in these patients.Methods.—A total of 30 female migraineurs and 30 physically and mentally healthy women matched for age and social status participated in a simple habituation test (auditory stimuli) and an achievement habituation test (mental arithmetic).Results.—Habituation was impaired in the electrodermal (skin conductance response), vasomotor (pulse volume amplitude), and cardiovascular (heart rate response) systems during the mental arithmetic test (achievement stimuli) in the migraineurs as compared to the healthy controls. With the simple stressor (auditory stimuli), however, habituation was impaired in the vasomotor system only. Consistent with these findings were the participants' verbal reports, which indicated significantly more subjective tension in the migraine group than in the control group during the calculation test.Conclusion.—Our results suggest that the mental arithmetic (achievement) habituation paradigm is an important tool for demonstrating reduced habituation in several specific components of the autonomic nervous system. Further research is needed to target the covariance of central and autonomic nervous system habituation phenomena in migraine.
Naratriptan in the Preventive Treatment of Refractory Transformed Migraine: A Prospective Pilot Study
Authors: Sheftell Fred D. , Rapoport Alan M. , Tepper Stewart J. , Bigal Marcelo E. 
Published: September 2007

Objective.—To assess the efficacy, safety, and tolerability of daily naratriptan in the preventive treatment of transformed migraine (TM) refractory to previous first line therapies.Background.—Limited evidence suggests that the triptans can be used in the preventive treatment of refractory headaches.Design/Methods.—We included subjects from 18 to 65 years old, with TM, with or without medication overuse (Silberstein and Lipton, 1996). All participants had previously failed at least two preventive medications. Concomitant, preventive medications were allowed if on a stable dose. After the baseline period, all patients received naratriptan 2.5 mg bid. The treatment phase lasted 3 months. The primary endpoint was change in headache frequency per month. Safety assessment included monthly ECGs, complete ophthalmologic exam, and monthly blood tests. Statistical analyses were performed using the intent‐to‐treat (ITT) population. We also conducted per‐protocol (PP) analyses.Results.—Our ITT population consisted of 30 subjects (79% female, mean age of 46.5 years). Mean headache frequency per month at baseline was 27.1 days and a significant reduction of headache frequency was obtained in 1 month (20.4, P < .001), 2 months (18.9, P < .001), and 3 months (19.0, P < .001). HIT scores were 64.3 at baseline, 57.4 after 1 month (P < .001), 55.7 after 2 months (P < .01), and 60 at 3 months (P < .05). The mean number of days using rescue medication was reduced from 17.7 at baseline, to 9.7 at 3 months (P < .001). Our PP population consisted of 22 subjects, and 54% had fewer than 15 headaches per month at the end of the study (converted to an episodic pattern). No serious adverse events were reported. No significant changes were observed in blood pressure or in heart rate. ECGs and ophthalmologic exam were unchanged from baseline.Conclusions.—(1) Daily use of naratriptan provided good preventive efficacy in an important subset of subjects with TM refractory to other preventive treatments. (2) The tolerability of this treatment was excellent. (3) Over a short period of time (3 months), no serious adverse events were reported, nor significant changes were found in the ECG or ophthalmologic evaluation.
Species‐specific physiological response of dinoflagellates to quantified small‐scale turbulence1
Authors: Berdalet Elisa , Peters Francesc , Koumandou V. Lila , Roldán Cristina , Guadayol Òscar , Estrada Marta 
Published: September 2007

Turbulence has been shown to alter different aspects of the physiology of some dinoflagellates. The response appears to be species‐specific and dependent on the experimental design and setup used to generate small‐scale turbulence. We examined the variability of the response of three dinoflagellate species to the turbulence, following the same experimental design used by Berdalet (1992) on Akashiwo sanguinea (Hirasaka) Ge. Hansen et Moestrup (=Gymnodinium nelsonii G. W. Martin). In all experiments, turbulence was generated by an orbital shaker at 100 rpm, which corresponded on bulk average, to dissipation rates (ε, quantified using an acoustic Doppler velocimeter) of ≈2 cm2 · s−3. Turbulence did not appreciably affect Gymnodinium sp., a small dinoflagellate. However, Alexandrium minutum Halim and Prorocentrum triestinum J. Schiller exhibited a reduced net growth rate (33% and 28%, respectively) when shaken during the exponential growth phase. Compared to the still cultures, the shaken treatments of A. minutum and P. triestinum increased the mean cell volume (up to 1.4‐ and 2.5‐fold, respectively) and the mean DNA content (up to 1.8‐ and 5.3‐fold, respectively). Cultures affected by turbulence recovered their normal cell properties when returned to still conditions. The swimming speed of the cells exposed to agitation was half that of the unshaken ones. Overall, the response of A. minutum and P. triestinum was similar, but with lower intensity, to that observed previously on A. sanguinea. We found no clear trends related to taxonomy or morphology.
The role of altruistic behavior, empathetic concern, and social responsibility motivation in blood donation behavior
Authors: Steele Whitney Randolph , Schreiber George B. , Guiltinan Anne , Nass Catharie , Glynn Simone A. , Wright David J. , Kessler Debra , Schlumpf Karen S. , Tu Yongling , Smith James W. , Garratty George ,   Retrovirus Epidemiology Donor Study
Published: September 2007

BACKGROUND:Blood donation can be described as a prosocial behavior, and donors often cite prosocial reasons such as altruism, empathy, or social responsibility for their willingness to donate. Previous studies have not quantitatively evaluated these characteristics in donors or examined how they relate to donation frequency.STUDY DESIGN AND METHODS:As part of a donor motivation study, 12,064 current and lapsed donors answered questions used to create an altruistic behavior, empathetic concern, and social responsibility motivation score for each donor. Analysis of variance was used to compare mean scores by demographics and donor status and to determine the influence of each variable on the mean number of donations in the past 5 years.RESULTS:The mean score for each prosocial characteristic appeared high, with lower scores in male and younger donors. Higher altruistic behavior and social responsibility motivation scores were associated with increased past donation frequency, but the effects were minor. Empathetic concern was not associated with prior donation. The largest differences in prior donations were by age and donor status, with older and current donors having given more frequently.CONCLUSION:Most blood donors appear to have high levels of the primary prosocial characteristics (altruism, empathy, and social responsibility) commonly thought to be the main motivators for donation, but these factors do not appear to be the ones most strongly related to donation frequency. Traditional donor appeals based on these characteristics may need to be supplemented by approaches that address practical concerns like convenience, community safety, or personal benefit.
Blood transfusions in children: a multi‐institutional analysis of practices and complications
Authors: Slonim Anthony D. , Joseph Jill G. , Turenne Wendy M. , Sharangpani Aditi , Luban Naomi L.C. 
Published: September 2007

BACKGROUND: Blood product transfusions are a valuable health‐care resource. Guidelines for transfusion exist, but variability in their application, particularly in children, remains. The risk factors that threaten transfusion safety are well established, but because their occurrence in children is rare, single‐institution studies have limited utility in determining the rates of occurrence. An epidemiologic approach that investigates blood transfusions in hospitalized children may help improve our understanding of transfused blood products in this vulnerable population.STUDY DESIGN AND METHODS: This was a nonconcurrent cohort study of pediatric patients not more than 18 years of age hospitalized from 2001 to 2003 at 35 academic children's hospitals that are members of the Pediatric Health Information System (PHIS).RESULTS: A total of 51,720 (4.8%) pediatric patients received blood product transfusions during the study period. Red blood cells (n = 44,632) and platelets (n = 14,274) were the two most frequently transfused products. The rate of transfusions was highest among children with neutropenia, agranulocytosis, and sickle cell crisis. Asian and American Indian patients had important differences in the rate of blood transfusions and their complications. Resource use in terms of length of stay and costs were higher in patients who received transfusion. Of those patients who received transfusions, 492 (0.95%) experienced a complication from the administered blood product. This accounted for a rate of complications of 10.7 per 1,000 units transfused.CONCLUSIONS: The administration of blood products to children is a common practice in academic children's hospitals. Complications associated with these transfused products are rare.
A multicenter pilot‐randomized controlled trial of the feasibility of an augmented red blood cell transfusion strategy for patients treated with induction chemotherapy for acute leukemia or stem cell transplantation
Authors: Webert Kathryn E. , Cook Richard J. , Couban Stephen , Carruthers Julie , Lee Ker‐Ai , Blajchman Morris A. , Lipton Jeffrey H. , Brandwein Joseph M. , Heddle Nancy M. 
Published: September 2007

BACKGROUND: Anemia may be an important factor contributing to an increased risk of bleeding, particularly in patients with thrombocytopenia.STUDY DESIGN AND METHODS: A multicenter, single‐blinded pilot randomized controlled trial (RCT) was performed to evaluate the feasibility of conducting a larger RCT to determine the effect of the hemoglobin (Hb) concentration on bleeding risk. Patients with acute leukemia receiving induction chemotherapy or those undergoing stem cell transplantation were assigned to one of two treatment groups: standard transfusion strategy (transfusion of 2 units of red blood cells [RBCs] when their Hb level was less than 80 g/L) or an augmented transfusion strategy (transfusion of 2 units of RBCs when their Hb level was less than 120 g/L).RESULTS: Sixty patients were enrolled: 29 in the control group and 31 in the experimental group. The proportions of patients experiencing clinically significant bleeding and the time to first bleed were not significantly different between the control and experimental groups. The experimental group received more RBC transfusions (transfusions/patient‐day) than the control group (0.233 vs. 0.151; relative risk, 1.56; 95% confidence interval, 1.16‐2.10; p = 0.003). The proportion of patient‐days with platelet (PLT) transfusions was not different between the experimental and control groups. The mean number of donor exposures (PLT and RBC transfusions) was not different between experimental and control groups. Bleeding symptoms were systematically documented.CONCLUSION: This pilot study thus indicated that it would be feasible to enroll the required number of patients to enable the performance of a large RCT to investigate the effect of Hb on bleeding risk in thrombocytopenic patients.
Proteomic analysis of supernatant from pooled buffy‐coat platelet concentrates throughout 7‐day storage
Authors: Glenister Kristen M. , Payne Katherine A. , Sparrow Rosemary L. 
Published: September 2007

BACKGROUND: The platelet (PLT) storage lesion remains incompletely understood. To gain a greater insight into the PLT storage lesion, a proteomic analysis of supernatant from leukofiltered pooled buffy‐coat PLT concentrates (PCs) was undertaken.STUDY DESIGN AND METHODS: PCs were prepared in PLT additive solution and stored according to standard blood bank procedures. Supernatant samples were collected throughout 7 days of storage. Maps of supernatant proteins were generated by two‐dimensional (2D) gel electrophoresis and mass spectrometry. Cytokine antibody microarrays and enzyme‐linked immunosorbent assay were used to investigate bioactive molecules.RESULTS: The 2D gel maps of PC supernatant proteins displayed many features of plasma protein maps. Several storage‐induced protein changes were identified including modifications to major plasma proteins. PLT‐derived proteins were also identified, including tremlike transcript 1 and integrin‐linked kinase, which may influence PLT–endothelium interactions. Cytokine antibody microarrays revealed a number of bioactive proteins that have not been previously associated with PCs produced for transfusion, such as brain‐derived neurotrophic factor (BDNF). The concentration of PLT‐derived cytokines including BDNF, CXCL7, epidermal growth factor, PLT‐derived growth factor (PDGF), and CCL5 significantly increased during storage of PCs. Extended storage from Day 5 to Day 7 caused significantly increased levels of BDNF, PDGF, and CCL5 in PC supernatant.CONCLUSION: Proteomic techniques provide valuable new insight into the effects of storage on PCs and the contribution of soluble proteins to the development of the PLT storage lesion and recipient responses to PLT transfusion.