bluuebunny/crossref_metadata_2025 huggingface dataset:
The Role of Statin Drugs in the Management of the Peripheral Vascular Patient
Authors: Samson Russell H.
Published: July 2008

The impact of statin therapy on established vascular conditions and recurrent disease is most relevant for long-term care. Patients receiving statin therapy have been shown to experience less recurrent stenosis following carotid endarterectomy and stent angioplasty, reduced cardiac events following cardiac and noncardiac vascular surgery, and reduction in aneurysm development. In patients with peripheral arterial disease, claudication distance is increased, as well as patency rates following infrainguinal arterial bypass grafting. Of note, statins drugs may also prove beneficial in the prevention of certain cancers, Alzheimer's disease, and osteoporosis (all diseases frequently seen concurrently in the patient with peripheral arterial disease). As such, it is becoming all the more necessary that vascular surgeons remain informed about clinical research initiatives related to statin use and lipid management in general. The following is a review of lipid metabolism as it applies to statins as well as a review of the beneficial effects of statins.
Single-Center Experience of Caval Thrombectomy in Patients With Renal Cell Carcinoma With Tumor Thrombus Extension Into the Inferior Vena Cava
Authors: Wang Grace J. , Carpenter Jeffrey P. , Fairman Ronald M. , Jackson Benjamin M. , Malkowicz Bruce , Van Arsdalen Keith N. , Woo Edward Y.
Published: July 2008

The objective of this study is to describe a single-center experience of caval thrombectomy in patients with renal cell carcinoma (RCC) and tumor thrombus extension into the inferior vena cava (IVC). We retrospectively reviewed 23 patients undergoing radical nephrectomy with caval thrombectomy. Follow-up included an office visit and computed tomography scan. Statistical comparisons were made using 2-sample t tests. Patients' ages ranged from 32 to 83 years (mean, 62 years; 18 male, 5 female). Tumor size ranged from 3 to 21 cm (mean, 8.6 cm). Tumor thrombus staging was based on the Nevus classification: level I (2/23), II (6/23), III (13/26), IV (2/23). Tumor thrombi were removed by means of digital extraction (20), Fogarty embolectomy (2), or endarterectomy (1-caval wall invasion). Lateral venorrhaphy was used for IVC repair in all cases. Hepatic mobilization and suprahepatic clamping were necessary in 14 patients. Clamp times were significantly different between the suprahepatic (SH) and infrahepatic (IH) groups (15 vs 9.4 minutes, P < .012). Mean blood loss was also significantly different (3.2 L vs 2 L, P < .045). In the SH group, 2 patients developed postoperative atrial fibrillation and 2 patients died (respiratory failure; missed enterotomy). The IH group had no perioperative morbidity or mortality. Median followup was 15 months (range, 1—54 months). Follow-up imaging was available for 19/23 patients. Ninety-five percent of patients had a patent IVC (18). One SH patient developed an IVC stenosis/thrombosis 12 months postoperatively with successful thrombolysis and stenting. There was a 16% (3/19) recurrence rate in follow-up, with all patients demonstrating renal vascular invasion and high Fuhrman grade upon final pathologic evaluation. Caval thrombectomy can be performed safely during radical nephrectomy for RCC with tumor thrombus extension. The need for suprahepatic clamping is associated with longer clamp times, increased blood loss, and increased morbidity and mortality. Lateral venorrhaphy with primary repair avoids complicated caval reconstructions and results in high patency rates, despite a not insignificant recurrence rate.
The Intersection of Aestheticism and Administrative Placement at Payton High
Authors: McCray Carlos R. , Beachum Floyd D. , Richardson Hayward R.
Published: July 2008

This case is centered on the term aestheticism, the discrimination or bias against those who do not possess the most desired physical qualities. In this particular case, the authors have chosen to highlight how African American administrators might be selected, assigned, or appointed based on their physical attributes and characteristics. The authors have chosen to reintroduce the term aestheticism, which originally appeared in Victorian England in the mid-1800s. It had a connotation of an appreciation and dissemination of middle class beauty with regard to art and style. However, it is the authors' goal in this reintroduction of aestheticism to “ismatize” it as a potential “ism” that highlights a void regarding the covert and overt discrimination that many individuals face on a daily basis as result of physical appearances that are not directly related to their race, ethnicity, religion, or gender.
Differences in lymphocyte developmental potential between human embryonic stem cell and umbilical cord blood–derived hematopoietic progenitor cells
Authors: Martin Colin H. , Woll Petter S. , Ni Zhenya , Zúñiga-Pflücker Juan Carlos , Kaufman Dan S.
Published: July 2008

Hematopoietic progenitor cells derived from human embryonic stem cells (hESCs) develop into diverse mature hematopoietic lineages, including lymphocytes. Whereas functional natural killer (NK) cells can be efficiently generated in vitro from hESC-derived CD34+ cells, studies of T- and B-cell development from hESCs have been much more limited. Here, we demonstrate that despite expressing functional Notch-1, CD34+ cells from hESCs did not derive T cells when cocultured with OP9 cells expressing Delta-like 1, or in fetal thymus organ culture. hESC-derived CD34+ cells also did not produce B cells in vitro. In contrast, CD34+ cells isolated from UCB routinely generated T and B cells when cultured in the same conditions. Notably, both undifferentiated hESCs, and sorted hESC-derived populations with hematopoietic developmental potential exhibited constitutive expression of ID family genes and of transcriptional targets of stem cell factor–induced signaling. These pathways both inhibit T-cell development and promote NK-cell development. Together, these results demonstrate fundamental differences between hESC-derived hematopoietic progenitors and analogous primary human cells. Therefore, hESCs can be more readily supported to differentiate into certain cell types than others, findings that have important implications for derivation of defined lineage-committed populations from hESCs.
A multicenter prospective phase 2 randomized study of extracorporeal photopheresis for treatment of chronic graft-versus-host disease
Authors: Flowers Mary E. D. , Apperley Jane F. , van Besien Koen , Elmaagacli Ahmet , Grigg Andrew , Reddy Vijay , Bacigalupo Andrea , Kolb Hans-Jochem , Bouzas Luis , Michallet Mauricette , Prince H. Miles , Knobler Robert , Parenti Dennis , Gallo Jose , Greinix Hildegard T.
Published: July 2008

Chronic graft-versus-host disease (cGVHD) is a major limitation of successful hematopoietic cell transplantation. The safety and efficacy of extracorporeal photopheresis (ECP) for 12 to 24 weeks together with standard therapy was compared with standard therapy alone in patients with cutaneous manifestations of cGVHD that could not be adequately controlled by corticosteroid treatment. The primary efficacy end point was a blinded quantitative comparison of percent change from baseline in Total Skin Score (TSS) of 10 body regions at week 12. Ninety-five patients were randomized to either ECP and standard therapy (n = 48) or standard therapy alone (n = 47). The median percentage improvement in TSS at week 12 was 14.5% for the ECP arm and 8.5% for the control arm (P = .48). The proportion of patients who had at least a 50% reduction in steroid dose and at least a 25% decrease from baseline in TSS was 8.3% in the ECP arm at week 12 and 0% in the control arm (P = .04). The nonblinded investigator assessment of skin complete or partial responses revealed a significant improvement in favor of ECP (P < .001). ECP was generally well tolerated. These results suggest that ECP may have a steroid-sparing effect in the treatment of cGVHD. Clinical trials registered at www.ClinicalTrials.gov as NCT00054613.
A dose-ranging study evaluating once-daily oral administration of the factor Xa inhibitor rivaroxaban in the treatment of patients with acute symptomatic deep vein thrombosis: the Einstein–DVT Dose-Ranging Study
Authors: Buller Harry R. , Lensing Anthonie W. A. , Prins Martin H. , Agnelli Giancarlo , Cohen Alexander , Gallus Alexander S. , Misselwitz Frank , Raskob Gary , Schellong Sebastian , Segers Annelise
Published: July 2008

We performed a randomized dose-ranging study, double-blind for rivaroxaban doses and open-label for the comparator (low-molecular-weight heparin followed by vitamin K antagonists) to assess the optimal dose of rivaroxaban for the treatment of deep vein thrombosis. A total of 543 patients with acute deep-venous thrombosis received rivaroxaban 20, 30, or 40 mg once daily or comparator. Treatment lasted for 84 days. The primary efficacy outcome was the 3-month incidence of the composite of symptomatic venous thromboembolic complications and asymptomatic deterioration in thrombotic burden as assessed by comparison of ultrasound and perfusion lung scanning at day 84 with baseline. The main safety outcome was the composite of major bleeding and clinically relevant nonmajor bleeding. A total of 449 (83%) of the 543 patients could be included in the per-protocol population. The primary efficacy outcome occurred in 6.1%, 5.4%, and 6.6% of the rivaroxaban 20-, 30-, and 40-mg treatment groups, respectively, and in 9.9% of those receiving standard therapy. The main safety outcome occurred in 5.9%, 6.0%, and 2.2% of the rivaroxaban 20-, 30-, and 40-mg treatment groups, respectively, and in 8.8% of those receiving standard therapy. These results with simple fixed-dose oral regimens justify phase 3 evaluations (www.ClinicalTrials.gov no.NCT00395772).
Development of methods for the genetic manipulation of Flavobacterium columnare
Authors: Staroscik Andrew M , Hunnicutt David W , Archibald Kate E , Nelson David R
Published: July 2008

Background

Flavobacterium columnare is the causative agent of columnaris disease, a disease affecting many freshwater fish species. Methods for the genetic manipulation for some of the species within the Bacteroidetes, including members of the genus Flavobacterium, have been described, but these methods were not adapted to work with F. columnare.

Results

As a first step toward developing a robust set of genetic tools for F. columnare, a protocol was developed to introduce the E. coli – Flavobacterium shuttle vector pCP29 into F. columnare strain C#2 by conjugal mating at an efficiency of 1.5 × 10-3 antibiotic-resistant transconjugants per recipient cell. Eight of eleven F. columnare strains tested were able to receive pCP29 using the protocol. pCP29 contains the cfxA and ermF genes, conferring both cefoxitin and erythromycin resistance to recipient cells. Selection for pCP29 introduction into F. columnare was dependent on cfxA, as ermF was found not to provide strong resistance to erythromycin. This is in contrast to other Flavobacterium species where ermF-based erythromycin resistance is strong. The green fluorescent protein gene (gfp) was introduced into F. columnare strains under the control of two different native Flavobacterium promoters, demonstrating the potential of this reporter system for the study of gene expression. The transposon Tn4351 was successfully introduced into F. columnare, but the method was dependent on selecting for erythromycin resistance. To work, low concentrations of antibiotic (1 μg ml-1) were used, and high levels of background growth occurred. These results demonstrate that Tn4351 functions in F. columnare but that it is not an effective mutagenesis tool due to its dependence on erythromycin selection. Attempts to generate mutants via homologous recombination met with limited success, suggesting that RecA dependent homologous recombination is rare in F. columnare.

Conclusion

The conjugation protocol developed as part of this study represents a significant first step towards the development of a robust set of genetic tools for the manipulation of F. columnare. The availability of this protocol will facilitate studies aimed at developing a deeper understanding of the virulence mechanisms of this important pathogen.
Pharmacological Switch in Aβ-Fiber Stimulation-Induced Spinal Transmission in Mice with Partial Sciatic Nerve Injury
Authors: Matsumoto Misaki , Xie Weijiao , Ma Lin , Ueda Hiroshi
Published: July 2008

Background:

We have previously demonstrated that different spinal transmissions are involved in the nociceptive behavior caused by electrical stimulation of Aβ-, Aδ- or C-fibers using a Neurometer® in naïve mice. In this study, we attempted to pharmacologically characterize the alteration in spinal transmission induced by partial sciatic nerve injury in terms of nociceptive behavior and phosphorylation of extracellular signal-regulated kinase (pERK) in the spinal dorsal horn.

Results:

Aβ-fiber responses (2000-Hz), which were selectively blocked by the AMPA/kainate antagonist CNQX in naïve mice, were hypersensitized but blocked by the NMDA receptor antagonists MK-801 and AP-5 in injured mice in an electrical stimulation-induced paw withdrawal (EPW) test. Although Aδ-fiber responses (250-Hz) were also hypersensitized by nerve injury, there was no change in the pharmacological characteristics of Aδ-fiber responses through NMDA receptors. On the contrary, C-fiber responses (5-Hz) were hyposensitized by nerve injury. Moreover, Aδ- and C-, but not Aβ-fiber stimulations significantly increased the number of pERK-positive neurons in the superficial spinal dorsal horns of naïve mice, and corresponding antagonists used in the EPW test inhibited this increase. In mice with nerve injury, Aβ- as well as Aδ-fiber stimulations significantly increased the number of pERK-positive neurons in the superficial spinal dorsal horn, whereas C-fiber stimulation decreased this number. The nerve injury-specific pERK increase induced by Aβ-stimulation was inhibited by MK-801 and AP-5, but not by CNQX. However, Aβ- and Aδ-stimulations did not affect the number or size of pERK-positive neurons in the dorsal root ganglion, whereas C-fiber-stimulation selectively decreased the number of pERK-positive neurons.

Conclusion:

These results suggest that Aβ-fiber perception is newly transmitted to spinal neurons, which originally receive only Aδ- and C-fiber-mediated pain transmission, through NMDA receptor-mediated mechanisms, in animals with nerve injury. This pharmacological switch in Aβ-fiber spinal transmission could be a mechanism underlying neuropathic allodynia.
Finger joint motion generated by individual extrinsic muscles: A cadaveric study
Authors: Nimbarte Ashish D. , Kaz Rodrigo , Li Zong-Ming
Published: July 2008

Background

Our understanding of finger functionality associated with the specific muscle is mostly based on the functional anatomy, and the exact motion effect associated with an individual muscle is still unknown. The purpose of this study was to examine phalangeal joints motion of the index finger generated by each extrinsic muscle.

Methods

Ten (6 female and 4 male) fresh-frozen cadaveric hands (age 55.2 ± 5.6 years) were minimally dissected to establish baseball sutures at the musculotendinous junctions of the index finger extrinsic muscles. Each tendon was loaded to 10% of its force potential and the motion generated at the metacarpophalangeal (MCP), proximal interphalangeal (PIP), and distal interphalangeal (DIP) joints was simultaneously recorded using a marker-based motion capture system.

Results

The flexor digitorum profundus (FDP) generated average flexion of 19.7, 41.8, and 29.4 degrees at the MCP, PIP, and DIP joints, respectively. The flexor digitorum superficialis (FDS) generated average flexion of 24.8 and 47.9 degrees at the MCP and PIP joints, respectively, and no motion at the DIP joints. The extensor digitorum communis (EDC) and extensor indicis proprius (EIP) generated average extension of 18.3, 15.2, 4.0 degrees and 15.4, 13.2, 3.7 degrees at the MCP, PIP and DIP joints, respectively. The FDP generated simultaneous motion at the PIP and DIP joints. However, the motion generated by the FDP and FDS, at the MCP joint lagged the motion generated at the PIP joint. The EDC and EIP generated simultaneous motion at the MCP and PIP joints.

Conclusion

The results of this study provide novel insights into the kinematic role of individual extrinsic muscles.
The Egg and I: Conception, Identity, and Abortion
Authors: Mills Eugene
Published: July 2008

Suppose you and I are “human beings” in the sense of human animals, members of the genus Homo. Given this supposition, this article argues first and foremost that (it's at least very plausible that) we originated not at the moment of our biological conception but either before or after. For biological conception is most plausibly seen as a momentous event in the continuing life of a preexisting organism—the egg—rather than a cataclysmic event ending one life and creating another. This article considers and rebuts the most likely challenges to this claim. This metaphysical point carries moral freight concerning abortion. This article surveys familiar “pro-life” principles and argues that if any of them raises moral qualms about the permissibility of aborting zygotic pregnancies, then these qualms apply equally (or at least almost equally) to the permissibility of contraception and abstinence. Hence no such principle provides a justification for condemning zygotic abortion while condoning abstinence or contraception.
On Specifying Truth-Conditions
Authors: Rayo Agustín
Published: July 2008

This essay is a study of ontological commitment, focused on the special case of arithmetical discourse. It tries to get clear about what would be involved in a defense of the claim that arithmetical assertions are ontologically innocent and about why ontological innocence matters. The essay proceeds by questioning traditional assumptions about the connection between the objects that are used to specify the truth-conditions of a sentence, on the one hand, and the objects whose existence is required in order for the truth-conditions thereby specified to be satisfied, on the other. This allows one to set forth an assignment of truth-conditions to arithmetical sentences whereby nothing is required of the world in order for the truth-conditions of a truth of pure arithmetic to be satisfied. The essay then argues that such an assignment can be used to account for the a priori knowability of certain arithmetical truths.
New developments on gill innervation: insights from a model vertebrate
Authors: Jonz Michael G. , Nurse Colin A.
Published: July 2008

The fish gill is a highly specialized and complex organ that performs a variety of important physiological functions. In this article, we briefly review the innervation of important structures of the branchial region, such as the gill filaments, respiratory lamellae and pseudobranch, and discuss the physiological significance of this innervation within the context of homeostatic functions of the gill, such as oxygen sensing and ion regulation. Studies in zebrafish utilizing techniques of confocal microscopy and immunolabelling, with specific antibodies against neuronal markers, have recently led to the characterization of innervation patterns in the gills not attained with traditional techniques of histochemistry and electron microscopy. We will discuss the association of putative sensory nerve fibres with O2-chemoreceptive neuroepithelial cells and the implications of dual sensory pathways for cardiorespiratory and vascular control. In addition, the idea of the neural control of ion regulation in the gill based on the apparent innervation of mitochondria-rich cells, and the role of innervation in the pseudobranch, will be presented.
Long-term changes in the chlorophyll fluorescence of bleached and recovering corals from Hawaii
Authors: Rodrigues Lisa J. , Grottoli Andréa G. , Lesser Michael P.
Published: July 2008

Chlorophyll fluorescence has been used to predict and monitor coral bleaching over short timescales (hours to days), but long-term changes during recovery remain largely unknown. To evaluate changes in fluorescence during long-term bleaching and recovery, Porites compressa and Montipora capitata corals were experimentally bleached in tanks at 30°C for 1 month, while control fragments were maintained at 27°C. A pulse amplitude modulated fluorometer measured the quantum yield of photosystem II fluorescence (Fv/Fm) of the zooxanthellae each week during bleaching, and after 0, 1.5, 4 and 8 months recovery. M. capitata appeared bleached 6 days sooner than P. compressa, yet their fluorescence patterns during bleaching did not significantly differ. Changes in minimum (Fo), maximum(Fm) and variable (Fv) fluorescence throughout bleaching and recovery indicated periods of initial photoprotection followed by photodamage in both species, with P. compressa requiring less time for photosystem II (PS II) repair than M. capitata. Fv/Fm fully recovered 6.5 months earlier in P. compressa than M. capitata, suggesting that the zooxanthellae of P. compressa were more resilient to bleaching stress.
Quantifying avian sexual dichromatism: a comparison of methods
Authors: Armenta Jessica K. , Dunn Peter O. , Whittingham Linda A.
Published: July 2008

Recent advances in portable spectrophotometers have allowed researchers to collect quantitative, objective data on colour. There are few comparisons of the different methods used to summarize and analyse spectrophotometer data,however. Using colour data on over 900 species of birds, we compared three methods of calculating sexual dichromatism using spectrophotometer data. We also compared sexual dichromatism calculated from spectrophotometer data, in both the ultraviolet (UV) and bird-visible range, with human estimates of sexual dichromatism. We found that all three methods, principal component analysis, segment classification and colour discriminability, yielded essentially comparable estimates of dichromatism for our extensive sample of birds. Certain methods may be better suited to a particular study depending on the questions addressed and the specific colours examined. We found that human visual estimates of dichromatism were similar to spectrophotometer estimates of dichromatism in the bird-visible range; however, human visual estimates did not predict the extent of UV dichromatism. Therefore, the conclusions of previous studies that relied on human vision to assess sexual dichromatism should be reliable. It is not possible, however, to predict a prioriwhether a species exhibits UV dichromatism without spectrophotometer measurements.
Post-prandial alkaline tide in freshwater rainbow trout: effects of meal anticipation on recovery from acid–base and ion regulatory disturbances
Authors: Cooper C. A. , Wilson R. W.
Published: July 2008

The post-feeding alkaline tide (elevated blood pH and HCO3–) has been well characterised in air-breathing animals, but to date this phenomenon has only been demonstrated in one piscine species, a marine elasmobranch. We have investigated the acid–base and ion regulatory responses of a freshwater teleost to voluntary feeding as well as to involuntary filling of the stomach via an indwelling gastric intubation tube. One group of rainbow trout(Oncorhynchus mykiss) were fed a 1% body mass ration of homogenised food via the gastric intubation tube. Another group fed voluntarily on a 1% body mass ration. Blood samples were taken via dorsal aortic catheters from fish in both groups before feeding and over the subsequent 72 h. Trout fed via the gastric intubation tube exhibited post-prandial metabolic alkalosis of the blood (pH and plasma HCO3– increases of up to ∼0.2 pH units and 3 mmol l–1, respectively), that was more than twofold greater than the voluntary feeding fish, and took three times as long to recover (72 versus 24 h). Arterial PCO2 was unchanged in both groups indicating that freshwater trout do not retain CO2 to compensate for a post-prandial alkaline tide. Although excretion of HCO3– to the water increased post-prandially, NH4+ excretion followed a similar pattern, such that net acid equivalent fluxes were unaffected. Thus, sites other than the gills or kidney must be responsible for recovery of blood acid–base status, with intestinal HCO3–secretion being a likely candidate. In addition, fish fed via the gastric intubation tube experienced a large (17 mmol l–1) but acute (6 h) drop in plasma chloride and a very large (53%) and long lasting decline in plasma magnesium concentration, that were absent in voluntarily feeding fish. These results further indicate a potentially important role for neuro-endocrine mediated mechanisms when fish feed voluntarily, in promoting the earlier initiation of compensatory responses that regulate blood ion levels and acid–base status. This aspect should also be considered when interpreting studies on other aspects of post-prandial physiology, where force feeding by gavage is commonly used in preference to voluntary feeding.
The alkaline tide and ammonia excretion after voluntary feeding in freshwater rainbow trout
Authors: Bucking Carol , Wood Chris M.
Published: July 2008

We investigated the potential acid–base and nitrogenous waste excretion challenges created by voluntary feeding in freshwater rainbow trout,with particular focus on the possible occurrence of an alkaline tide (a metabolic alkalosis created by gastric HCl secretion during digestion). Plasma metabolites (glucose, urea and ammonia) were measured at various time points before and after voluntary feeding to satiation (approximately 5% body mass meal of dry commercial pellets), as was the net flux of ammonia and titratable alkalinity to the water from unfed and fed fish. Arterial blood, sampled by indwelling catheter, was examined for post-prandial effects on pH, plasma bicarbonate and plasma CO2 tension. There was no significant change in plasma glucose or urea concentrations following feeding, whereas plasma ammonia transiently increased, peaking at threefold above resting values at 12 h after the meal and remaining elevated for 24 h. The increased plasma ammonia was correlated with an increase in net ammonia excretion to the water, with fed fish significantly elevating their net ammonia excretion two- to threefold between 12 and 48 h post feeding. These parameters did not change in unfed control fish. Fed fish likewise increased the net titratable base flux to the water by approximately threefold, which resulted in a transition from a small net acid flux seen in unfed fish to a large net base flux in fed fish. Over 48 h, this resulted in a net excretion of 13 867 μmol kg–1more base to the external water than in unfed fish. The arterial blood exhibited a corresponding rise in pH (between 6 and 12 h) and plasma bicarbonate (between 3 and 12 h) following feeding; however, no respiratory compensation was observed, as PaCO2 remained constant. Overall, there was evidence of numerous challenges created by feeding in a freshwater teleost fish, including the occurrence of an alkaline tide, and its compensation by excretion of base to the external water. The possible influence of feeding ecology and environmental salinity on these challenges, as well as discrepancies in the literature, are discussed.
Size- and age-dependent changes in adductor muscle swimming physiology of the scallopAequipecten opercularis
Authors: Philipp Eva E. R. , Schmidt Maike , Gsottbauer Carina , Sänger Alexandra M. , Abele Doris
Published: July 2008

The decline of cellular and especially mitochondrial functions with age is,among other causes, held responsible for a decrease in physiological fitness and exercise capacity during lifetime. We investigated size- and age-related changes in the physiology of exercising specimens of the short lived swimming scallop Aequipecten opercularis (maximum life span 8 to 10 years)from the Isle of Man, UK. A. opercularis swim mainly to avoid predators, and a decrease in swimming abilities would increase the risk of capture and lower the rates of survival. Bigger (older) individuals were found to have lower mitochondrial volume density and aerobic capacities (citrate synthase activity and adenylates) as well as less anaerobic capacity deduced from the amount of glycogen stored in muscle tissue. Changes in redox potential, tissue pH and the loss of glutathione in the swimming muscle during the exercise were more pronounced in young compared to older individuals. This indicates that older individuals can more effectively stabilize cellular homeostasis during repeated exercise than younger animals but with a possible fitness cost as the change in physiology with age and size might result in a changed escape response behaviour towards predators.
Differences in the sleep architecture of forager and young honeybees(Apis mellifera)
Authors: Eban-Rothschild Ada D. , Bloch Guy
Published: July 2008

Honeybee (Apis mellifera) foragers are among the first invertebrates for which sleep behavior has been described. Foragers (typically older than 21 days) have strong circadian rhythms; they are active during the day, and sleep during the night. We explored whether young bees (∼3 days of age), which are typically active around-the-clock with no circadian rhythms, also exhibit sleep behavior. We combined 24-hour video recordings,detailed behavioral observations, and analyses of response thresholds to a light pulse for individually housed bees in various arousal states. We characterized three sleep stages in foragers on the basis of differences in body posture, bout duration, antennae movements and response threshold. Young bees exhibited sleep behavior consisting of the same three stages as observed in foragers. Sleep was interrupted by brief awakenings, which were as frequent in young bees as in foragers. Beyond these similarities, we found differences in the sleep architecture of young bees and foragers. Young bees passed more frequently between the three sleep stages, and stayed longer in the lightest sleep stage than foragers. These differences in sleep architecture may represent developmental and/or environmentally induced variations in the neuronal network underlying sleep in honeybees. To the best of our knowledge,this is the first evidence for plasticity in sleep behavior in insects.
Branchial expression and localization of SLC9A2 and SLC9A3 sodium/hydrogen exchangers and their possible role in acid–base regulation in freshwater rainbow trout (Oncorhynchus mykiss)
Authors: Ivanis G. , Esbaugh A. J. , Perry S. F.
Published: July 2008

Experiments were conducted on adult rainbow trout (Oncorhynchus mykiss) to test the hypothesis that SLC9 Na+/H+exchangers (SLC9A2, NHE2; and SLC9A3, NHE3) on the gill epithelium are localized specifically to a subset of mitochondria-rich cells (MRCs) that are unable to bind peanut lectin agglutinin (PNA). This cell type, termed the PNA– MRC, is a sub-type of MRC believed to function in Na+ uptake and acid excretion. A technique using biotinylated PNA was used to distinguish between the PNA– and PNA+MRCs on fixed gill sections. In contrast to expectations, both NHE2 (mRNA) and NHE3 (protein) were confined to cells enriched with Na+/K+-ATPase and capable of binding PNA. Thus, in trout, NHE2 and NHE3 are localized to PNA+ MRCs, the cells previously believed to be responsible for Cl– uptake and base excretion. Levels of mRNA for NHE2, the predominant isoform in the gill, were increased during 72 h of hypercapnic acidosis; NHE3 mRNA and protein levels were unaffected. Because plasma cortisol levels were increased during hypercapnia (from 35.3±9.4 to 100.1±30.9 ng ml–1), the effects of experimentally elevated cortisol levels on NHE expression were investigated. The elevation of plasma cortisol using intraperitoneal implants caused a significant increase in NHE2 mRNA expression without affecting NHE3 mRNA or protein abundance. Thus, we suggest that NHE2 contributes to acid–base regulation during hypercapnia owing to its transcriptional regulation by cortisol. The finding of NHE expression in PNA+ MRCs is discussed with reference to current models of ionic and acid–base regulation in teleost fish.
In vivoregulation of rainbow trout lipolysis by catecholamines
Authors: Magnoni Leonardo , Vaillancourt Eric , Weber Jean-Michel
Published: July 2008

Lipolysis provides fatty acids that support key life processes by functioning as membrane components, oxidative fuels and metabolic signals. It is commonly measured as the rate of appearance of glycerol(Ra glycerol). Its in vivo regulation by catecholamines has been thoroughly investigated in mammals, but little information is available for ectotherms. Therefore, the goals of this study were, first, to characterize the effects of the catecholamines norepinephrine(NE) and epinephrine (Epi) on the lipolytic rate of intact rainbow trout(Oncorhynchus mykiss) and, second, to determine whether the plasma glycerol concentration is a reliable index of Ra glycerol. Our results show that baseline Ra glycerol (4.6±0.4μmol kg–1 min–1) is inhibited by NE(–56%), instead of being stimulated, as in mammals, whereas Epi has the same activating effect in both groups of vertebrates (+167%). NE-induced inhibition of fish lipolysis might play a particularly important role during aquatic hypoxia, when survival often depends on regulated metabolic depression. The plasma glycerol concentration is a poor predictor of Ra glycerol, and it should not be used as an index of lipolysis. Trout maintain a particularly high baseline lipolytic rate because only 13% of the fatty acids provided are sufficient to support total energy expenditure, whereas the remaining fatty acids must undergo reesterification(87%).
Insulin regulates the expression of several metabolism-related genes in the liver and primary hepatocytes of rainbow trout (Oncorhynchus mykiss)
Authors: Plagnes-Juan Elisabeth , Lansard Marine , Seiliez Iban , Médale Françoise , Corraze Geneviève , Kaushik Sadasivam , Panserat Stéphane , Skiba-Cassy Sandrine
Published: July 2008

Rainbow trout have a limited ability to use dietary carbohydrates efficiently and are considered to be glucose intolerant. Administration of carbohydrates results in persistent hyperglycemia and impairs post-prandial down regulation of gluconeogenesis despite normal insulin secretion. Since gluconeogenic genes are mainly under insulin control, we put forward the hypothesis that the transcriptional function of insulin as a whole may be impaired in the trout liver. In order to test this hypothesis, we performed intraperitoneal administration of bovine insulin to fasted rainbow trout and also subjected rainbow trout primary hepatocytes to insulin and/or glucose stimulation. We demonstrate that insulin was able to activate Akt, a key element in the insulin signaling pathway, and to regulate hepatic metabolism-related target genes both in vivo and in vitro. In the same way as in mammals, insulin decreased mRNA expression of gluconeogenic genes, including glucose 6-phosphatase (G6Pase),fructose 1,6-bisphosphatase (FBPase) and phosphoenolpyruvate carboxykinase (PEPCK). Insulin also limited the expression of carnitine palmitoyltransferase 1 (CPT1), a limiting enzyme of fatty acid β-oxidation. In vitro studies revealed that, as in mammals,glucose is an important regulator of some insulin target genes such as the glycolytic enzyme pyruvate kinase (PK) and the lipogenic enzyme fatty acid synthase (FAS). Interestingly, glucose also stimulates expression of glucokinase (GK), which has no equivalent in mammals. This study demonstrates that insulin possesses the intrinsic ability to regulate hepatic gene expression in rainbow trout, suggesting that other hormonal or metabolic factors may counteract some of the post-prandial actions of insulin.
The elusive crypt olfactory receptor neuron: evidence for its stimulation by amino acids and cAMP pathway agonists
Authors: Vielma Alex , Ardiles Alvaro , Delgado Luz , Schmachtenberg Oliver
Published: July 2008

Crypt olfactory receptor neurons (ORNs) are a third type of chemosensory neuron along with ciliated and microvillous ORNs in the olfactory epithelium of fishes, but their functional role is still unknown. To investigate their odorant response properties and possible transduction pathways, we recorded crypt ORN activity with calcium imaging and the patch clamp technique in its cell-attached mode in combination with odorant and agonist stimulation. Bile salts and putative fish pheromones did not elicit responses with either method, but the cells frequently responded to amino acids, with excitation and intracellular calcium signals. 8Br-cAMP and IBMX plus forskolin stimulated over 40% of crypt ORNs and triggered calcium signals in a similar percentage. Furthermore, crypt ORNs were immunoreactive to an antiserum against adenylate cyclase III. Together, these data suggest the presence of a cAMP transduction pathway, which might transduce odorants such as amino acids.
Context-dependent olfactory enhancement of optomotor flight control inDrosophila
Authors: Chow Dawnis M. , Frye Mark A.
Published: July 2008

Sensing and following the chemical plume of food odors is a fundamental challenge faced by many organisms. For flying insects, the task is complicated by wind that distorts the plume and buffets the fly. To maintain an upwind heading, and thus stabilize their orientation in a plume, insects such as flies and moths make use of strong context-specific visual equilibrium reflexes. For example, flying straight requires the regulation of image rotation across the eye, whereas minimizing side-slip and avoiding a collision require regulation of image expansion. In flies, visual rotation stabilizes plume tracking, but rotation and expansion optomotor responses are controlled by separate visual pathways. Are olfactory signals integrated with optomotor responses in a manner dependent upon visual context? We addressed this question by investigating the effect of an attractive food odor on active optomotor flight control. Odorant caused flies both to increase aerodynamic power output and to steer straighter. However, when challenged with wide-field optic flow, odor resulted in enhanced amplitude rotation responses but reduced amplitude expansion responses. For both visual conditions, flies tracked motion signals more closely in odor, an indication of increased saliency. These results suggest a simple search algorithm by which olfactory signals improve the salience of visual stimuli and modify optomotor control in a context-dependent manner, thereby enabling an animal to fly straight up a plume and approach odiferous objects.
Differential roles of p38-MAPK and JNKs in mediating early protection or apoptosis in the hyperthermic perfused amphibian heart
Authors: Gaitanaki Catherine , Mastri Michalis , Aggeli Ioanna-Katerina S. , Beis Isidoros
Published: July 2008

In the present study the activation of p38 mitogen-activated protein kinase(p38-MAPK) and c-Jun N-terminal kinases (JNKs) by hyperthermia was investigated in the isolated perfused Rana ridibunda heart. Hyperthermia (42°C) was found to profoundly stimulate p38-MAPK phosphorylation within 0.5 h, with maximal values being attained at 1 h[4.503(±0.577)-fold relative to control, P<0.01]. JNKs were also activated under these conditions in a sustained manner for at least 4 h[2.641(±0.217)-fold relative to control, P<0.01]. Regarding their substrates, heat shock protein 27 (Hsp27) was maximally phosphorylated at 1 h [2.261(±0.327)-fold relative to control, P<0.01] and c-Jun at a later phase [3 h: 5.367(±0.081)-fold relative to control, P<0.001]. Hyperthermia-induced p38-MAPK activation was found to be dependent on the Na+/H+ exchanger 1 (NHE1) and was also suppressed by catalase (Cat) and superoxide dismutase (SOD), implicating the generation of reactive oxygen species (ROS). ROS were also implicated in the activation of JNKs by hyperthermia, with the Na+/K+-ATPase acting as a mediator of this effect at an early stage and the NHE1 getting involved at a later time point. Finally, JNKs were found to be the principal mediators of the apoptosis induced under hyperthermic conditions, as their inhibition abolished poly(ADP-ribose)polymerase (PARP) cleavage after 4 h at 42°C. Overall, to our knowledge,this study highlights for the first time the variable mediators implicated in the transduction of the hyperthermic signal in the isolated perfused heart of an ectotherm and deciphers a potential salutary effect of p38-MAPK as well as the fundamental role of JNKs in the induced apoptosis.
Poly(vinylspirobifluorene): Synthesis and Properties of a Novel Styrenic Polymer
Authors: Ishiwari Fumitaka , Kawasaki Shinichi , Koyama Yasuhito , Takata Toshikazu
Published: July 2008

Synthesis and properties of a new class of styrenic polymer are reported. The radical polymerization of 2-vinyl-9,9′-spirobifluorene yielded high molecular weight poly(vinylspirobifluorene) with high thermal stability and high solubility, which gave a self-standing transparent film with high refractive index.
Facile Preparation of Highly Luminescent InP Nanocrystals by a Solvothermal Route
Authors: Li Chunliang , Ando Masanori , Murase Norio
Published: July 2008

Monodisperse InP nanocrystals were prepared by a facile one-pot solvothermal route via the pyrolysis reaction between indium chloride and tris(dimethylamino)phosphine at relatively low temperatures (150–180 °C). The InP nanocrystals after size-selective precipitation had a well-crystallized zinc blende structure, a narrow size distribution, and distinguishable absorption peaks. Application of HF treatment in combination with photoetching increased their emission efficiency to 58% while their emission wavelengths were tunable from green to red.
Chiral Tetrafluorobenzobarrelenes as Highly Efficient Ligands for the Rhodium-catalyzed Asymmetric 1,4-Addition of Arylboronic Acids
Authors: Nishimura Takahiro , Nagaosa Makoto , Hayashi Tamio
Published: July 2008

New C2-symmetric chiral diene ligands bearing a tetrafluorobenzobarrelene framework and (−)-menthyl groups as chiral auxiliaries were prepared through [4 + 2] cycloaddition of 1,4-bis((−)-menthoxymethyl)benzene with tetrafluorobenzyne. The diene ligands realized the rhodium-catalyzed asymmetric addition of arylboronic acids to α,β-unsaturated carbonyl compounds giving β-arylcarbonyl compounds in high yields with high enantioselectivity.
Lithium Cuprate (Li2CuO2): A New Possible Ceramic Material for CO2 Chemisorption
Authors: Palacios-Romero Luis M , Pfeiffer Heriberto
Published: July 2008

Li2CuO2 was used for the CO2 chemisorption process. Li2CuO2 was thermally treated under a flux of CO2, dynamically (from 25 to 1000 °C) and isothermically. The results clearly showed that Li2CuO2 is able to chemisorb CO2 in a wider range of temperatures than those presented by other lithium ceramics. Therefore, this ceramic may become a new option as CO2 captor.
Hydration Is an Important Factor to Regulate Thermodynamic Stability of a DNA Duplex under Molecular Crowding Conditions
Authors: Koumoto Kazuya , Ochiai Hirofumi , Sugimoto Naoki
Published: July 2008

By using a DNA duplex, (5′-GTTACTATATGA-3′/5′-TCATATAGTAAC-3′) under molecular crowding conditions, it was revealed that hydration plays a significant role in the stability of the duplex, in contrast to viscosity and dielectric constant which have little effect.
Bulk Heterojunction Organic Photovoltaic Cell Fabricated with a p-Type Conjugated Star-shaped Molecule
Authors: Lee Tae Wan , Kim Dae Cheol , Kang Nam Su , Yu Jae Woong , Cho Min Ju , Kim Kyung Hwan , Choi Dong Hoon
Published: July 2008

A new multibranched crystalline molecule was synthesized through Horner–Emmons reactions using hexyl-substituted thiophene-based carbaldehydes as dendrons and benzene-1,2,4,5-tetramethylphosphonic acid octaethyl ester as the core unit. The molecule was employed to fabricate organic photovoltaic (OPV) cells with methanofullerene [6,6]-phenyl C61-butyric acid methyl ester (PCBM). Poly(3-hexylthiophene) (P3HT) was also used as a dopant to improve the film quality and power conversion efficiency. As a result, the short-circuit current density and open circuit voltage were increased when P3HT was added into 4(HPBT) and PCBM dyad, resulting in a higher power conversion efficiency of around 0.6%.
Three-Dimensional Analysis of Carbon Nanofibers by Cross-sectional TEM Observations
Authors: Ogihara Hitoshi , Takenaka Sakae , Yamanaka Ichiro , Tanabe Eishi , Genseki Akira , Koki Jun , Otsuka Kiyoshi
Published: July 2008

Cross-sectional TEM images of carbon nanofibers formed through methane decomposition over Ni/SiO2 catalysts were observed by using an ultramicrotome. The TEM images indicated that carbon nanofibers have regular hexagonal prism structures.
Synthesis of Highly Conjugated Arylpropenylidene-1,3-diazin-2-ones via Paterno–Büchi Reaction by Photoreaction of 5-Fluoro-1,3-dimethyluracil with 1-Methoxynaphthalenes
Authors: Seki Koh-ichi , Aizawa Kazuya , Sugaoi Tatsuyuki , Kimura Masayuki , Ohkura Kazue
Published: July 2008

In contrast to photoreactions of 5-fluoro-1,3-dimethyluracil (5-FDMU) with various naphthalenes including 2-methoxynaphthalenes that proceeds in a manner to give ethenoquinazolines through 1,4-cycloaddition, UV-irradiation of a mixture of 5-FDMU and naphthalenes with a methoxy group at C-1 gave rise to the formation of novel cycloadducts, methyl 2-[(1E)-3-(5-fluoro-1,3-dimethyl-2-oxo-1,3-dihydropyrimidin-4-ylidene)prop-1-enyl]benzoates, derived from the novel aromatic Paterno–Büchi type cycloaddition, followed by a concomitant disruption of the initially formed oxetane moiety.
One-dimensional Arrangement of Plasmonic Nanoparticle Chains by Marangoni Flow and Meniscus Recession
Authors: Kang Youngjong
Published: July 2008

Flexible Au nanoparticle chains were spontaneously aligned into a linear structure at several hundred micrometer scale during evaporation process. 1D alignment was achieved by using Marangoni flow and sequential meniscus recession. Evaporation speed and the incline of substrate strongly affected the resulting structures.
Near Infrared Spectroscopy for the Control of Osmo-Air Dehydrated Apple Rings
Authors: Barzaghi Stefania , Gobbi Serena , Torreggiani Danila , Tornielli Cristina , Giangiacomo Roberto
Published: July 2008

The aim of this work was to investigate the feasibility of near infrared (NIR) spectroscopy both in quantifying the residual water content of osmo-air dehydrated apple rings and in differentiating them on the basis of the sugar solution used in the osmotic pretreatment so identifying the osmotic syrup used. In order to achieve this, a set of products obtained by different processing conditions was created. Apple rings were dipped for different lengths of time (30, 60 and 90 min) in three different sugar solutions at the same water activity (aw = 0.90): sucrose (59% wt /wt), maltose (62% wt /wt) and a mixture (53% wt /wt) of fructose, glucose and sucrose having the same composition as apple. Air drying was then performed at different temperatures (70°, 80°, 90°C) and the obtained osmo-air dehydrated apple rings were packed in polypropylene film under vacuum in order to avoid water absorption phenomena. NIR spectra, in the range 10,000–4000 cm−1, were recorded directly on packed apple rings using a FT-NIR spectrometer equipped with fiber optic probe. In calibrating the residual water content the coefficient of determination (R2) was 0.93, the RPD value was 3.33 and RER value was 13.79, which could be considered, for our purposes, suitable for controlling the dehydration process. Moreover, applying a classification statistic method on NIR data, such as PLS discrimination analysis, it was also possible to identify correctly which sugar solution was used in the osmotic pre-treatment independently of the conditions used. Two-dimensional correlation analysis was also carried out, in order to investigate how the ratios between the main constituents, sugars and water, involved in the osmo-air dehydration varied as a function of the process variable used.