bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hormonal regulation of glucose clearance in lactating northern elephant seals (Mirounga angustirostris)
Authors: Fowler Melinda A. , Champagne Cory D. , Houser Dorian S. , Crocker Daniel E. 
Published: September 2008

SUMMARY
Northern elephant seals exhibit the rare strategy of fasting and lactating concomitantly. We investigated hormonal regulation of glucose clearance in northern elephant seals using glucose tolerance tests (GTT) performed early in lactation and again just prior to weaning. For comparison, identical measurements were made on separate females late in the molt fast. Serial blood samples were used to assess glucose clearance and hormone responses for 3 h post glucose injection. Plasma glucose remained elevated at the end of the sampling period in all groups. Glucose clearance rates were not significantly different among test groups. A significant insulin response was observed in early lactation, no significant response was observed late in lactation and an intermediate response was observed late in the molt fast. The insulin response to a glucose load decreased with adipose tissue proportions. Plasma glucagon decreased significantly following GTT in early and late lactation, although the magnitude of the depression was small in comparison to other species. Hypoinsulemia may be critical to facilitate net lipolysis late in lactation. Consistently low glucose clearance among test groups suggests insulin insensitivity within peripheral tissues. Glucagon suppression independent of insulin release suggests modification of the typical insulin–glucagon counter-regulation. These findings suggest that metabolic features of diabetic-like conditions may be adaptive in the context of long-term fasting.
Pelvic fin locomotor function in fishes: three-dimensional kinematics in rainbow trout (Oncorhynchus mykiss)
Authors: Standen E. M. 
Published: September 2008

SUMMARYThe paired pelvic fins in fishes have been the subject of few studies. Early work that amputated pelvic fins concluded that these fins had very limited, and mainly passive, stabilizing function during locomotion. This paper is the first to use three-dimensional kinematic analysis of paired pelvic fins to formulate hypotheses of pelvic fin function. Rainbow trout(Oncorhynchus mykiss) were filmed swimming steadily at slow speeds(0.13–1.36 BL s–1) and during manoeuvres(0.21–0.84 BL s–1) in a variable speed flow tank. Two high-speed cameras filmed ventral and lateral views simultaneously,enabling three-dimensional analysis of fin motion. During steady swimming,pelvic fins oscillate in a regular contralateral cycle. This cyclic oscillation appears to have active and passive components, and may function to dampen body oscillation and stabilize body position. During manoeuvres, pelvic fins move variably but appear to act as trimming foils, helping to stabilize and return the body to a steady swimming posture after a manoeuvre has been initiated. Fins on the inside of the turn move differently from those on the outside of the turn, creating an asymmetric motion. This paper challenges the understanding that pelvic fins have a limited and passive function by proposing three new hypotheses. First, pelvic fins in rainbow trout have complex three-dimensional kinematics during slow-speed steady swimming and manoeuvres. Second, pelvic fins are moved actively against imposed hydrodynamic loads. Third, pelvic fins appear to produce powered correction forces during steady swimming and trim correction forces during manoeuvres.
Consequences of buoyancy to the maneuvering capabilities of a foot-propelled aquatic predator, the great cormorant (Phalcrocorax carbo sinensis)
Authors: Ribak Gal , Weihs Daniel , Arad Zeev 
Published: September 2008

SUMMARY
Great cormorants are foot-propelled aquatic divers utilizing a region of the water column where their underwater foraging behavior is affected by their buoyancy. While swimming horizontally underwater, cormorants use downward lift forces generated by their body and tail to overcome their buoyancy. Here we assess the potential of this swimming strategy for controlling maneuvers in the vertical plane. We recorded the birds swimming through a submerged obstacle course and analyzed their maneuvers. The birds reduced swimming speed by only 12% to maneuver and were able to turn upward and then downward in the sagittal plane at a minimal turning radius of 32±4 cm (40% body length). Using a quasi-steady approach, we estimated the time-line for hydrodynamic forces and the force-moments produced while maneuvering. We found that the tail is responsible for the pitch of the body while motions of the body, tail, neck and feet generate forces normal (vertically) to the swimming direction that interact with buoyancy to change the birds' trajectory. Vertical maneuvers in cormorants are asymmetric in energy cost. When turning upward, the birds use their buoyancy but they must work harder to turn downward. Lift forces generated by the body were always directed ventrally. Propulsion improves the ability to make tight turns when the center of the turn is ventral to the birds. The neck produced only a small portion (10%) of the normal vertical forces but its length may allow prey capture at the end of pursuit, within the minimum turning radius.
Swimming kinematics and hydrodynamic imaging in the blind Mexican cave fish (Astyanax fasciatus)
Authors: Windsor Shane P. , Tan Delfinn , Montgomery John C. 
Published: September 2008

SUMMARYBlind Mexican cave fish (Astyanax fasciatus) lack a functioning visual system, and are known to use self-generated water motion to sense their surroundings; an ability termed hydrodynamic imaging. Nearby objects distort the flow field created by the motion of the fish. These flow distortions are sensed by the mechanosensory lateral line. Here we used image processing to measure detailed kinematics, along with a new behavioural technique, to investigate the effectiveness of hydrodynamic imaging. In a head-on approach to a wall, fish reacted to avoid collision with the wall at an average distance of only 4.0±0.2 mm. Contrary to previous expectation, there was no significant correlation between the swimming velocity of the fish and the distance at which they reacted to the wall. Hydrodynamic imaging appeared to be most effective when the fish were gliding with their bodies held straight, with the proportion of approaches to the wall that resulted in collision increasing from 11% to 73% if the fish were beating their tails rather than gliding as they neared the wall. The swimming kinematics of the fish were significantly different when swimming beside a wall compared with when swimming away from any walls. Blind cave fish frequently touched walls when swimming alongside them, indicating that they use both tactile and hydrodynamic information in this situation. We conclude that although hydrodynamic imaging can provide effective collision avoidance, it is a short-range sense that may often be used synergistically with direct touch.
Is a parallel elastic element responsible for the enhancement of steady-state muscle force following active stretch?
Authors: Bullimore S. R. , MacIntosh B. R. , Herzog W. 
Published: September 2008

SUMMARYFor over 50 years, it has been recognised that muscles from many different species of animals are able to generate a higher steady-state isometric force after active stretch than during a purely isometric contraction at the same length. This is known as `residual force enhancement' (rFE). The mechanism underlying this phenomenon remains controversial. One proposal is that an elastic element parallel to the cross-bridges becomes stiffer, or is engaged,when the muscle is activated and generates force when stretched. If this is indeed the sole mechanism, then rFE should be eliminated by subsequently shortening the muscle by a distance equal to or greater than the initial stretch. We tested this hypothesis using six intact single fibres from frog lumbrical muscle. The fibres were activated and stretched to generate rFE and then rapidly shortened by between 25% and 700% of the initial stretch distance. In contrast to previous reports, we found that rapid shortening induced a depression of subsequent isometric force. We used two methods to account for this force depression when calculating rFE, thereby obtaining upper and lower bounds for the true rFE. With both methods of calculation, rFE was significantly greater than zero when shortening distance was equal to stretch distance (P=0.0004 and P=0.03, respectively). Therefore, our hypothesis was not supported. We conclude that rFE is unlikely to be generated solely by a parallel elastic element.
Strong Interaction at the Palladium/Alumina Interface of Membrane during Hydrogen Permeation at Elevated Temperature
Authors: Okazaki Junya , Ikeda Takuji , Tanaka David A Pacheco , Tanco Margot A Llosa , Wakui Yoshito , Sato Koichi , Mizukami Fujio , Suzuki Toshishige M 
Published: September 2008

Abstract
Hydrogen flux through palladium membrane supported on α-alumina significantly decreased during permeation testing at elevated temperatures (650–850 °C). Strong interaction between palladium and α-alumina, i.e., formation of less hydrogen permeable palladium–aluminum alloy was suggested via reduction of alumina under hydrogen atmosphere at high temperature. Migration of aluminum to the membrane top surface might obstruct the dissociative adsorption of hydrogen molecules.
Synthesis of gem-Difluoroalkenes via β-Fluoride Elimination of Organorhodium(I)
Authors: Miura Tomoya , Ito Yoshiteru , Murakami Masahiro 
Published: September 2008

Abstract
Treatment of α-(trifluoromethyl)styrenes with arylboronic esters and MeMgCl in the presence of a rhodium(I) catalyst affords gem-difluoroalkenes. The reaction proceeds through the addition of arylrhodium(I) species across the electron-deficient carbon–carbon double bond and the subsequent β-fluoride elimination.
The Rhythms of Life: An Appreciation of Michelangelo Antonioni, Extreme Aesthete of the Real
Authors: Williams James S. 
Published: September 2008

Abstract
This essay assesses Antonioni's oeuvre in its totality, focusing in particular on its constant negotiation of two extremes: documentary and melodrama. The essay argues that Antonioni's is a visionary project which, by achieving a genuine encounter between art and technology, extends an earlier tradition of the European avant-garde.
Heritage, Commerce, and Museal Display: Toward a New Typology of Historical Exhibition in the United States
Authors: Gordon Tammy S. 
Published: September 2008

Abstract
Recent social and economic trends in the United States, most importantly the increased marketability of local heritage and the national dialogue on identity, have contributed to the proliferation of historical exhibits in the United States, often in nonmuseum spaces like retail and service settings. Scholarship on historical exhibition, however, has largely focused on exhibits in large, professionalized museums. Dividing exhibit types into categories of academic, corporate, community, entrepreneurial, and vernacular, this article explores the diverse ways in which the exhibition medium emerges from different settings, social conditions, and epistemologies.
“United We Commemorate”: The Kentucky Pioneer Memorial Association, James Isenberg, and Early Twentieth-Century Heritage Tourism
Authors: Moore William D. 
Published: September 2008

Abstract
The Kentucky Pioneer Memorial Association created an innovative tourist attraction in Harrodsburg, Kentucky, between 1910 and 1935. Led by James L. Isenberg, a boosterist entrepreneur, the KPMA reconstituted the cabin in which Lincoln's parents were married, reconstructed a settlers' stockade, established a museum, secured governmental funding, and forged a coalition in support of heritage tourism. The KPMA indicates that historic preservation and development in the early twentieth century were not exclusively the domains of patricians retreating to a pre-industrial past to mitigate change. Isenberg, a descendent of recent immigrants, established his site as an economic engine for his community.
Noggin Enhances Dopamine Neuron Production from Human Embryonic Stem Cells and Improves Behavioral Outcome After Transplantation into Parkinsonian Rats
Authors: Chiba Shunmei , Lee Young Mook , Zhou Wenbo , Freed Curt R. 
Published: September 2008

Abstract
Symptoms of Parkinson's disease have been improved by transplantation of fetal dopamine neurons recovered from aborted fetal tissue, but tissue recovery is difficult. Human embryonic stem cells may provide unlimited cells for transplantation if they can be converted to dopamine neurons and survive transplantation into brain. We have found that the bone morphogenic protein antagonist Noggin increased the number of dopamine neurons generated in vitro from human and mouse embryonic stem cells differentiated on mouse PA6 stromal cells. Noggin effects were seen with either early (for mouse, days 0–7, and for human, days 0–9) or continuous treatment. After transplant into cyclosporin-immunosuppressed rats, human dopamine neurons improved apomorphine circling in direct relation to the number of surviving dopamine neurons, which was fivefold greater after Noggin treatment than with control human embryonic stem cell transplants differentiated only on PA6 cells. We conclude that Noggin promotes dopamine neuron differentiation and survival from human and mouse embryonic stem cells.
Disclosure of potential conflicts of interest is found at the end of this article.
Soluble Flt-1 Regulates Flk-1 Activation to Control Hematopoietic and Endothelial Development in an Oxygen-Responsive Manner
Authors: Purpura Kelly A. , George Sophia H.L. , Dang Stephen M. , Choi Kyunghee , Nagy Andras , Zandstra Peter W. 
Published: September 2008

Abstract
Vascular endothelial growth factor (VEGF) and the vascular endothelial growth factor receptors (VEGFRs) regulate the development of hemogenic mesoderm. Oxygen concentration-mediated activation of hypoxia-inducible factor targets such as VEGF may serve as the molecular link between the microenvironment and mesoderm-derived blood and endothelial cell specification. We used controlled-oxygen microenvironments to manipulate the generation of hemogenic mesoderm and its derivatives from embryonic stem cells. Our studies revealed a novel role for soluble VEGFR1 (sFlt-1) in modulating hemogenic mesoderm fate between hematopoietic and endothelial cells. Parallel measurements of VEGF and VEGFRs demonstrated that sFlt-1 regulates VEGFR2 (Flk-1) activation in both a developmental-stage-dependent and oxygen-dependent manner. Early transient Flk-1 signaling occurred in hypoxia because of low levels of sFlt-1 and high levels of VEGF, yielding VEGF-dependent generation of hemogenic mesoderm. Sustained (or delayed) Flk-1 activation preferentially yielded hemogenic mesoderm-derived endothelial cells. In contrast, delayed (sFlt-1-mediated) inhibition of Flk-1 signaling resulted in hemogenic mesoderm-derived blood progenitor cells. Ex vivo analyses of primary mouse embryo-derived cells and analysis of transgenic mice secreting a Flt-1-Fc fusion protein (Fc, the region of an antibody which is constant and binds to receptors) support a hypothesis whereby microenvironmentally regulated blood and endothelial tissue specification is enabled by the temporally variant control of the levels of Flk-1 activation.
Disclosure of potential conflicts of interest is found at the end of this article.
IFATS Collection: Fibroblast Growth Factor-2-Induced Hepatocyte Growth Factor Secretion by Adipose-Derived Stromal Cells Inhibits Postinjury Fibrogenesis Through a c-Jun N-Terminal Kinase-Dependent Mechanism
Authors: Suga Hirotaka , Eto Hitomi , Shigeura Tomokuni , Inoue Keita , Aoi Noriyuki , Kato Harunosuke , Nishimura Satoshi , Manabe Ichiro , Gonda Koichi , Yoshimura Kotaro 
Published: September 2008

Abstract
Adipose-derived stem/stromal cells (ASCs) not only function as tissue-specific progenitor cells but also are multipotent and secrete angiogenic growth factors, such as hepatocyte growth factor (HGF), under certain circumstances. However, the biological role and regulatory mechanism of this secretion have not been well studied. We focused on the role of ASCs in the process of adipose tissue injury and repair and found that among injury-associated growth factors, fibroblast growth factor-2 (FGF-2) strongly promoted ASC proliferation and HGF secretion through a c-Jun N-terminal kinase (JNK) signaling pathway. In a mouse model of ischemia-reperfusion injury of adipose tissue, regenerative changes following necrotic and apoptotic changes were seen for 2 weeks. Acute release of FGF-2 by injured adipose tissue was followed by upregulation of HGF. During the adipose tissue remodeling process, adipose-derived 5-bromo-2-deoxyuridine-positive cells were shown to be ASCs (CD31−CD34+). Inhibition of JNK signaling inhibited the activation of ASCs and delayed the remodeling process. In addition, inhibition of FGF-2 or JNK signaling prevented postinjury upregulation of HGF and led to increased fibrogenesis in the injured adipose tissue. Increased fibrogenesis also followed the administration of a neutralizing antibody against HGF. FGF-2 released from injured tissue acts through a JNK signaling pathway to stimulate ASCs to proliferate and secrete HGF, contributing to the regeneration of adipose tissue and suppression of fibrogenesis after injury. This study revealed a functional role for ASCs in the response to injury and provides new insight into the therapeutic potential of ASCs.
Long‐Term Clinical Results on the Use of Bone‐Replacement Grafts in the Treatment of Intrabony Periodontal Defects. Comparison of the Use of Autogenous Bone Graft Plus Calcium Sulfate to Autogenous Bone Graft Covered With a Bioabsorbable Membrane
Authors: Orsini Marco , Orsini Giovanna , Benlloch Dunia , Aranda Juan Jose , Sanz Mariano 
Published: September 2008

Background: Many clinical investigations have demonstrated the benefits of different regenerative approaches in the treatment of infrabony defects. The aim of this investigation was to evaluate the results obtained with the combination of autogenous bone grafting plus calcium sulfate and to compare this outcome with the results obtained using autogenous bone grafting with a bioabsorbable membrane.Methods: Twelve subjects participated in this split‐mouth trial. Twelve 2‐ or 3‐wall periodontal defects were treated with a combination of autogenous bone grafting plus calcium sulfate (test) and were compared to 12 defects treated with autogenous bone grafting with a bioabsorbable membrane (control). Before surgery, subjects were instructed in oral hygiene techniques, and scaling and root planing were completed. Surgery was identical for both groups except for the regenerative material. After healing, subjects followed a periodontal maintenance program. Probing depth (PD), clinical attachment level, and bleeding on probing were recorded at baseline, 6 months, and 6 years.Results: There were no statistical differences between test and control defects at baseline. At 6 months, there was a PD reduction of 4.3 ± 1.0 mm in the control group and 4.4 ± 1.1 mm in the test group. There was a clinical attachment gain of 3.5 ± 1.1 mm in the control group and 3.6 ± 1.0 mm in the test group. At 6 years, there was a PD reduction of 3.3 ± 1.0 mm in the control group and 4.2 ± 1.2 mm in the test group. There was a clinical attachment gain of 2.6 ± 1.2 mm in the control group and 2.4 ± 1.1 mm in the test group. Differences between treatment groups were not statistically significant at 6 months or 6 years.Conclusion: Both therapies led to significant short‐ and long‐term improvements in the outcome variables assessed.
Estrogen Regulates Expression of Osteoprotegerin and RANKL in Human Periodontal Ligament Cells Through Estrogen Receptor Beta
Authors: Liang Li , Yu Ji‐feng , Wang Yan , Ding Yin 
Published: September 2008

Background: The function of periodontal ligament (PDL) cells may be affected by estrogen. PDL cells synthesize the receptor activator of nuclear factor‐kappa B ligand (RANKL) and its decoy receptor, namely, osteoprotegerin (OPG), which directly controls osteoclastogenesis. The primary aim of this study was to investigate how estrogen affects the expression of OPG and RANKL in human PDL (hPDL) cells.Methods: We used a short interfering RNA technique to inhibit estrogen receptor beta (ERβ) expression in hPDL cells; the cells were cultured with a saturating concentration of 17β‐estradiol (10−7 M) for 48 hours. Changes in the expression of OPG and RANKL were determined by reverse transcription‐polymerase chain reaction and supported by Western blot analysis.Results: Estradiol caused an increase in OPG expression and decreased RANKL expression in hPDL cells. However, it had no effect on the expression of OPG and RANKL in hPDL–siERβ (the short interfering RNA to block ER β) cells.Conclusion: Estrogen may play an important role in exerting antiresorptive effects on alveolar bone, at least in part, by increasing the expression level of OPG versus that of RANKL via ERβ in hPDL cells.
Resolution of Oral Lesions After Tobacco Cessation
Authors: Shibly Othman , Cummings K. Michael , Zambon Joseph J. 
Published: September 2008

Background:Dentists and other health care professionals are familiar with the impact of tobacco on oral and general health. However, oral health care professionals do not often provide tobacco‐cessation counseling to their patients, thus reflecting a significant disconnect between research and clinical practice. This report demonstrates the benefits of tobacco cessation in resolving oral lesions and improving overall periodontal and oral health.Methods:A 51‐year‐old white male presented to the University at Buffalo, School of Dental Medicine clinic requesting an oral and periodontal examination as part of a presurgical protocol prior to cardiac surgery. A review of the patient's history from a health questionnaire revealed that he was using smokeless tobacco every day. An oral examination revealed several white lesions (5 × 10 mm) on the maxillary right and left labial mucosa. The patient was provided with tobacco‐cessation counseling as well as oral hygiene instructions and professional dental prophylaxis.Results:An oral examination 2 weeks after tobacco cessation revealed complete resolution of the oral lesions and overall improvement of periodontal and oral health.Conclusion:Although the findings presented in this article are based only on a single case report, the improvement in the patient's oral health after cessation of tobacco use was dramatic and reinforces the belief that tobacco‐cessation counseling should be a routine component of the standard of care for tobacco‐using patients.