bluuebunny/crossref_metadata_2025 huggingface dataset:
The impact of Epstein-Barr virus status on clinical outcome in diffuse large B-cell lymphoma
Authors: Park Sarah , Lee Jeeyun , Ko Young Hyeh , Han Arum , Jun Hyun Jung , Lee Sang Chul , Hwang In Gyu , Park Yeon Hee , Ahn Jin Seok , Jung Chul Won , Kim Kihyun , Ahn Yong Chan , Kang Won Ki , Park Keunchil , Kim Won Seog
Published: March 2007

To define prognostic impact of Epstein-Barr virus (EBV) infection in diffuse large B-cell lymphoma (DLBCL), we investigated EBV status in patients with DLBCL. In all, 380 slides from paraffin-embedded tissue were available for analysis by EBV-encoded RNA-1 (EBER) in situ hybridization, and 34 cases (9.0%) were identified as EBER-positive. EBER positivity was significantly associated with age greater than 60 years (P = .005), more advanced stage (P < .001), more than one extranodal involvement (P = .009), higher International Prognostic Index (IPI) risk group (P = .015), presence of B symptom (P = .004), and poorer outcome to initial treatment (P = .006). The EBER+ patients with DLBCL demonstrated substantially poorer overall survival (EBER+ vs EBER− 35.8 months [95% confidence interval (CI), 0-114.1 months] vs not reached, P = .026) and progression-free survival (EBER+ vs EBER− 12.8 months [95% CI, 0-31.8 months] vs 35.8 months [95% CI, 0-114.1 months], respectively (P = .018). In nongerminal center B-cell–like subtype, EBER in situ hybridization positivity retained its statistical significance at the multivariate level (P = .045). Nongerminal center B-cell–like patients with DLBCL with EBER positivity showed substantially poorer overall survival with 2.9-fold (95% CI, 1.1-8.1) risk for death. Taken together, DLBCL patients with EBER in situ hybridization+ pursued more rapidly deteriorating clinical course with poorer treatment response, survival, and progression-free survival.
Rapid transit in the immune cells: the role of mRNA turnover regulation
Authors: Khabar Khalid S A
Published: March 2007

There have been recent, significant advances about the role of mRNA turnover in controlling gene expression in immune cells. Post-transcriptional regulation of gene expression contributes to the characteristics of many of the processes underlying the immune response by ensuring early, rapid, and transient action. The emphasis of this review is on current work that deals with the regulation of mRNA decay during innate immunity against microbes and T cell activation as a model of the adaptive response.
Protection of CD8+ T cells from activation-induced cell death by IL-18
Authors: Li Wen , Kashiwamura Shin-ichiro , Ueda Haruyasu , Sekiyama Atsuo , Okamura Haruki
Published: March 2007

Role of IL-18 on proliferation and survival of CD8+ T cells, activated by immobilized anti-CD3 antibody (anti-CD3), was examined. Proliferation and survival of activated T cells, especially that of CD8+ T cells, were impaired by IL-18 deficiency [IL-18 knockout (KO)]. After 3 days of culture with anti-CD3, the number of living CD8+ T cells from IL-18KO mice was ∼25% of that from wild-type (WT) mice but was increased to the same level as WT cells by the addition of IL-18. The expression of IL-18 receptors (IL-18Rs), particularly IL-18Rβ chain, in naïve CD8+ T cells was very low but elevated after stimulation with anti-CD3. Blockade of IL-18R by anti-IL-18R antibody on activated WT CD8+ T cells resulted in reduction of living cells, suggesting that IL-18 promotes survival of proliferating CD8+ T cells. Levels of Bcl-2 in activated IL-18KO CD8+ T cells were lower than those in WT cells but were raised by exogenous IL-18. Blockade of IL-18R on WT CD8+ T cells decreased the expression of surface markers CD122 and CD94, which are related to cell viability, and the expression of these markers was increased by exogenous IL-18 in IL-18KO cells. These results suggest that IL-18 acts directly on activated CD8+ T cells through IL-18Rs and promotes their survival to expand the population.
Localization of hCAP-18 on the surface of chemoattractant-stimulated human granulocytes: analysis using two novel hCAP-18-specific monoclonal antibodies
Authors: Stie Jamal , Jesaitis Andrew V , Lord Connie I , Gripentrog Jeannie M , Taylor Ross M , Burritt James B , Jesaitis Algirdas J
Published: March 2007

The well-described antimicrobial and immunoregulatory properties of human cathelicidin antimicrobial protein 18 (hCAP-18) derive in part from the ability of its proteolytic fragment, LL-37 (a.k.a. CAP-37), to associate with activated immune and epithelial cells during inflammation. We now show a stable association between hCAP-18 and the cell surface of formyl-Met-Leu-Phe (fMLF)-stimulated neutrophils using two novel hCAP-18-specific mAb, H7 and N9, which recognize a single 16-kDa band, identified by N-terminal sequencing and mass spectrometry as hCAP-18. Phage display analysis of epitope-binding sites showed that both mAb probably recognize a similar five amino acid sequence near the C terminus of the prodomain. Immunoblot analysis of degranulated neutrophil supernatants resulted in mAb recognition of the 14-kDa prodomain of hCAP-18. Subcellular fractionation of unstimulated neutrophils on density gradients showed expected cosedimentation of hCAP-18 with specific granule lactoferrin (LF). fMLF stimulation resulted in an average 25% release of specific granule hCAP-18, with ∼15% of the total cellular hCAP-18 recovered from culture media, and ∼10% and ∼75%, respectively, codistributing with plasma membrane alkaline phosphatase and specific granule LF. Surface association of hCAP-18 on fMLF-stimulated neutrophils was confirmed by immunofluorescence microscopy and flow cytometry analysis, which also suggested a significant up-regulation of surface hCAP-18 on cytochalasin B-pretreated, fully degranulated neutrophils. hCAP-18 surface association was labile to 10 mM NaOH treatment but resistant to 1 M NaCl and also partitioned into the detergent phase following Triton X-114 solubilization, possibly suggesting a stable association with one or more integral membrane proteins. We conclude that fMLF stimulation promotes redistribution of hCAP-18 to the surface of human neutrophils.
SHP‐1 Tyrosine Phosphatase in Human Erythrocytes
Authors: BRAGADIN MARCANTONIO , ION‐POPA FLORINA , CLARI GIULIO , BORDIN LUCIANA
Published: April 2007

Abstract:  SHP‐1 is a SH2‐domain containing protein Tyr‐phosphatase expressed in hematopoietic cell lines, which is hypothesized to play a negative role in signal transduction. In human erythrocytes, the phospho‐Tyr level of proteins, mainly transmembrane band 3, is closely controlled by the antithetic activity of Tyr‐protein kinases and phosphatases, resulting in a dephosphorylated state. Only after particular stimuli, as with oxidizing agents, diamide or pervanadate, or thiol alkylating compound, N‐ethyl maleimide (NEM), Tyr‐phosphorylation of band 3 can be triggered, inhibiting Tyr‐phosphatase action and inducing erythrocyte membrane reorganization. We demonstrate that, in human erythrocytes, SHP‐1 is present in membranes from resting cells, but in 5% of the protein amount. Interestingly, this amount increases up to threefold following NEM treatment of intact cells, whereas diamide and pervanadate do not alter the normal protein location. In addition, SHP‐1 translocation from cytosol to membrane is not affected by band 3 P‐Tyr level, because it is not mediated by the SH2‐P‐Tyr recruitment mechanism, and localizes into the cytoskeletal compartment. Band 3 is the target of SHP‐1, which dephosphorylates Tyr 8, 21, and 904.
These findings support the idea that, in human erythrocytes, the normal level of Tyr‐phosphorylation of membrane protein, mainly band 3, must be downregulated. We hypothesize that the presence of both SHP‐2 and SHP‐1 ensures band 3 dephosphorylation in different conditions: SHP‐2, through interaction of its SH2 domain/s to P‐Tyr protein, is regulated by the band 3 Tyr‐phosphorylation level; SHP‐1 may be involved by simple membrane rearrangement.
Cardioprotective Action of Urocortin in Early Pre‐ and Postconditioning
Authors: CSEREPES BARBARA , JANCSÓ GÁBOR , GASZ BALÁZS , RÁCZ BOGLÁRKA , FERENC ANDREA , BENKÓ LÁSZLÓ , BORSICZKY BALÁZS , KÜRTHY MÁRIA , FERENCZ SANDOR , LANTOS JÁNOS , GÁL JÁNOS , ARATÓ ENDRE , MISETA ATTILA , WÉBER GYÖRGY , RÓTH ELIZABETH
Published: April 2007

Abstract:  Pre‐ and postconditioning are powerful endogenous adaptive phenomenon of the organism whereby different stimuli enhance the tolerance against various types of stress. Urocortin (Ucn), member of the corticotropin‐releasing factor (CRF) family has potent effects on the cardiovascular system. The aim of this article was to investigate the action of Ucn on cultured cardiomyocytes in the process of pre‐ and postconditioning. Isolated neonatal rat ventricular myocytes were preconditioned with adenosine, simulated ischemia, and Ucn (10‐min treatment followed by 10‐min reperfusion/recovery). For detecting the effect of alternative types of preconditioning, necrosis enzyme (lactate dehydrogenase [LDH]) release, vital staining (trypan blue), and ratio of apoptosis/necrosis were examined after cardiac cells were exposed to 3‐h sustained ischemia and 2‐h reperfusion. Same parameters were measured in the postconditioned groups (30‐ or 60‐min ischemia followed by postconditioning with 10‐min ischemic stimulus or Ucn and 2‐h reperfusion). Cells exposed to 3‐h ischemia followed by 2‐h reperfusion were shown as control. Our results show that LDH release a number of trypan blue‐stained dead cells and the ratio of apoptotized and necrotized cells was decreased in all preconditioned groups compared with control group. In postconditioned groups LDH content of culture medium, trypan blue‐positive cardiomyocytes, and the rate of apoptotic/necrotic cells was reduced contrasted with non‐postconditioned group. We can conclude that preconditioning with Ucn induced such a powerful cell protective effect as adenosine and ischemia. Furthermore, postconditioning with Ucn after 60‐min ischemia was more cardioprotective than ischemic postconditioning.
Dosage Effects of Ginkgolide B on Ethanol‐Induced Cell Death in Human Hepatoma G2 Cells
Authors: CHAN WEN‐HSIUNG , HSUUW YAN‐DER
Published: April 2007

Abstract:  Ginkgolide B is a major active component of Ginkgo biloba extracts, which has been shown to confer anticancer effects by inducing apoptosis or inhibiting oxidative stress generation.
Ethanol induces a wide range of cellular toxicities, many of which have been linked to free radical generation. To further elucidate the cellular effects of ginkgolide B, we examined the dose–response effect of ginkgolide B on ethanol‐induced toxicity in human Hep G2 cells. TUNEL and MTT assays revealed that ethanol (50–400 mM) induced apoptotic cell death in human Hep G2 cells, and that this effect was inhibited by low (5–25 μM) doses of ginkgolide B, but enhanced by high (50–100 μM) doses of ginkgolide B. Additional experiments revealed that ethanol treatment directly increased intracellular oxidative stress; this effect was enhanced by high doses of ginkgolide B but decreased following treatment with low concentrations of ginkgolide B. The dose–response effects of ginkgolide B on reactive oxygen species (ROS) generation were directly correlated with cell apoptotic biochemical changes including c‐Jun N‐terminal kinase (JNK) activation, caspase‐3 activation, and DNA fragmentation. These results indicate that treatment dosage may determine the effect of ginkgolide B on ethanol‐induced ROS generation and cell apoptosis, and support the notion that an appropriate dosage of ginkgolide B may aid in decreasing the toxic effects of ethanol.
Attenuation of Aβ‐Induced Apoptosis of Plant Extract (Saengshik) Mediated by the Inhibition of Mitochondrial Dysfunction and Antioxidative Effect
Authors: CHEN CHU‐YUE , JANG JUNG‐HEE , PARK MI HYUN , HWANG SUNG JOO , SURH YOUNG‐JOON , PARK OCK JIN
Published: April 2007

Abstract:  Recently, considerable attention has been focused on dietary manipulation of oxidative and/or nitrosative damage on neuronal cells. In this article, a neuroprotective effect of plant (Saengshik) extracts was investigated. Rat pheochromocytoma (PC12), cells treated with β‐amyloid underwent apoptotic death as determined by positive in situ terminal end‐labeling (TUNEL staining), decreased mitochondrial transmembrane potential, and elevated caspase‐3 activity co‐occurring with enhanced MDA accumulation and the reduction of GSH levels. Saengshik pretreatment attenuated β‐amyloid‐induced apoptosis in PC12 cells possibly by inhibiting mitochondrial dysfunction and exerting antioxidant properties. Saengshik pretreatment inhibited the loss of mitochondrial membrane potentials and reduced the activation of caspase‐3. The in vitro antioxidant activities of Saengshik extracts were verified by the 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) method and superoxide dismutase (SOD) mimetic activity.
In β‐amyloid‐challenged PC12 cells, Saengshik prevented the production of ROS, decreased the level of MDA, and elevated GSH. The potential of Saengshik as one of the neuroprotective regimens has been suggested through this article, and the combination with defined pharmaceuticals or other dietary antioxidants may provide a better therapeutic or preventive advantage for the management of Alzheimer's disease.
The role of GW/P-bodies in RNA processing and silencing
Authors: Jakymiw Andrew , Pauley Kaleb M. , Li Songqing , Ikeda Keigo , Lian Shangli , Eystathioy Theophany , Satoh Minoru , Fritzler Marvin J. , Chan Edward K. L.
Published: March 2007

GW bodies, also known as mammalian P-bodies, are cytoplasmic foci involved in the post-transcriptional regulation of eukaryotic gene expression. Recently, GW bodies have been linked to RNA interference and demonstrated to be important for short-interfering-RNA- and microRNA-mediated mRNA decay and translational repression. Evidence indicates that both passenger and guide strands of short-interfering RNA duplexes can localize to GW bodies, thereby indicating that RNA-induced silencing complexes may be activated within these cytoplasmic centers. Formation of GW bodies appears to depend on both specific protein factors and RNA, in particular, microRNA. Work over the past few years has significantly increased our understanding of the biology of GW bodies, revealing that they are specialized cell components that spatially regulate mRNA turnover in various biological processes. The formation of GW bodies appears to depend on both specific protein factors and RNA, in particular, microRNA. Here, we propose a working model for GW body assembly in terms of its relationship to RNA interference. In this process, one or more heteromeric protein complexes accumulate in successive steps into larger ribonucleoprotein structures.
A vacuolar-type H+-ATPase and a Na+/H+exchanger contribute to intracellular pH regulation in cockroach salivary ducts
Authors: Hille Carsten , Walz Bernd
Published: March 2007

Cells of the dopaminergically innervated salivary ducts in the cockroach Periplaneta americana have a vacuolar-type H+-ATPase(V-ATPase) of unknown function in their apical membrane. We have studied whether dopamine affects intracellular pH (pHi) in duct cells and whether and to what extent the apical V-ATPase contributes to pHiregulation. pHi measurements with double-barrelled pH-sensitive microelectrodes and the fluorescent dye BCECF have revealed: (1) the steady-state pHi is 7.3±0.1; (2) dopamine induces a dose-dependent acidification up to pH 6.9±0.1 at 1 μmol l–1 dopamine, EC50 at 30 nmol l–1dopamine; (3) V-ATPase inhibition with concanamycin A or Na+-free physiological saline (PS) does not affect the steady-state pHi; (4)concanamycin A, Na+ -free PS and Na+/H+exchange inhibition with 5-(N-ethyl-N-isopropyl)-amiloride(EIPA) each reduce the rate of pHi recovery from a dopamine-induced acidification or an acidification induced by an NH4Cl pulse; (5)pHi recovery after NH4Cl-induced acidification is almost completely blocked by concanamycin A in Na+-free PS or by concanamycin A applied together with EIPA; (6) pHi recovery after dopamine-induced acidification is also completely blocked by concanamycin A in Na+-free PS but only partially blocked by concanamycin A applied together with EIPA. We therefore conclude that the apical V-ATPase and a basolateral Na+/H+ exchange play a minor role in steady-state pHi regulation but contribute both to H+extrusion after an acute dopamine- or NH4Cl-induced acid load.
Mechanics of cutting maneuvers by ostriches (Struthio camelus)
Authors: Jindrich Devin L. , Smith Nicola C. , Jespers Karin , Wilson Alan M.
Published: March 2007

We studied the strategies used by cursorial bipeds (ostriches) to maneuver during running. Eight ostriches were induced to run along a trackway and execute turns. Ground reaction forces and three-dimensional kinematics of the body and leg joints were simultaneously recorded, allowing calculation of joint angles and quasi-static net joint torques. Sidesteps, where the leg on the outside of the turn changes the movement direction, and crossovers using the inside leg, occurred with nearly equal frequency. Ostriches executed maneuvers using a simple control strategy that required minimal changes to leg kinematics or net torque production at individual joints. Although ostriches did use acceleration or braking forces to control body rotation, their morphology allowed for both crossovers and sidesteps to be accomplished with minimal net acceleratory/braking force production. Moreover, body roll and ab/adduction of the leg shifted the foot position away from the turn direction, reducing the acceleratory/braking forces required to prevent under-or over-rotation and aligning the leg with the ground reaction force.
Osmoregulation in elephant fishCallorhinchus milii(Holocephali), with special reference to the rectal gland
Authors: Hyodo Susumu , Bell Justin D. , Healy Jillian M. , Kaneko Toyoji , Hasegawa Sanae , Takei Yoshio , Donald John A. , Toop Tes
Published: March 2007

Osmoregulatory mechanisms in holocephalan fishes are poorly understood except that these fish are known to conduct urea-based osmoregulation as in elasmobranchs. We, therefore, examined changes in plasma parameters of elephant fish Callorhinchus milii, after gradual transfer to concentrated (120%) or diluted (80%) seawater (SW). In control fish, plasma Na and urea concentrations were about 300 mmol l–1 and 450 mmol l–1, respectively. These values were equivalent to those of sharks and rays, but the plasma urea concentration of elephant fish was considerably higher than that reported for chimaeras, another holocephalan. After transfer to 120% SW, plasma osmolality, urea and ion concentrations were increased, whereas transfer to 80% SW resulted in a fall in these parameters. The rises in ion concentrations were notable after transfer to 120% SW,whereas urea concentration decreased predominantly following transfer to 80%SW. In elephant fish, we could not find a discrete rectal gland. Instead,approximately 10 tubular structures were located in the wall of post-valvular intestine. Each tubular structure was composed of a putative salt-secreting component consisting of a single-layered columnar epithelium, which was stained with an anti-Na+,K+-ATPase serum. Furthermore,Na+,K+-ATPase activity in the tubular structures was significantly increased after acute transfer of fish to concentrated SW(115%). These results suggest that the tubular structures are a rectal gland equivalent, functioning as a salt-secreting organ. Since the rectal gland of elephant fish is well developed compared to that of Southern chimaera, the salt-secreting ability may be higher in elephant fish than chimaeras, which may account for the lower plasma NaCl concentration in elephant fish compared to other chimaeras. Since elephant fish have also attracted attention from a viewpoint of genome science, the availability of fish for physiological studies will make this species an excellent model in holocephalan fish group.
Annual changes in body mass and resting metabolism in captive barnacle geese (Branta leucopsis): the importance of wing moult
Authors: Portugal Steven J. , Green Jonathan A. , Butler Patrick J.
Published: March 2007

Many different physiological changes have been observed in wild waterfowl during the flightless stage of wing moult, including a loss of body mass. We aimed to determine whether captive barnacle geese (Branta leucopsis)would show the characteristic decrease in body mass during their wing moult,even though they had unlimited and unrestricted access to food. Fourteen captive geese were weighed at 1–2-week intervals for two complete years. During the flightless period of the moult, body mass decreased by approximately 25% from the pre-moult value. To understand the basis of this change, the rate of oxygen consumption was measured during daytime and nighttime at six points in the second year, and at three points (before,during and after wing moult) behavioural observations were made. Measurements of the rate of oxygen consumption showed an 80% increase above that of the nonmoulting periods of the year. We propose that metabolism was increased during moult because of the cost of feather synthesis. Although food was available, the captive birds chose not to forage and instead increased the proportion of time spent resting. It is likely that this behaviour in response to wing moult is a strategy to avoid predation in the wild. Thus, the innate nature of this behaviour has potential survival value for wild birds of this species. We conclude that the increase in metabolism led to the use of endogenous energy reserves because the birds reduced rather than increased their food intake rates, and as a result, the barnacle geese lost body mass during wing moult.
What comes first, the zebra finch or the egg: temperature-dependent reproductive, physiological and behavioural plasticity in egg-laying zebra finches
Authors: Salvante Katrina G. , Walzem Rosemary L. , Williams Tony D.
Published: March 2007

Avian reproduction is generally timed to synchronize chick-rearing with periods of increased food abundance. Consequently, the energetically demanding period of egg production may coincide with periods of lower food availability,fluctuating temperature and more unstable weather. Little is known about the physiological mechanisms underlying temperature-induced variation in egg production. We therefore examined the influence of low ambient temperature(7°C vs 21°C) on reproductive output (e.g. egg mass, clutch size, laying interval, laying rate), daily food consumption and lipid variables in zebra finches Taeniopygia guttata. When faced with egg production at 7°C, laying zebra finches increased energy intake by 12.67 kJ day–1, and were thus able to maintain body condition (e.g. body mass, fat and muscle score) and circulating triacylglyceride at levels comparable to those at 21°C. However, when producing eggs at 7°C,females took longer to initiate egg laying (6.5 vs 6.1 days at 21°C), and ultimately laid fewer eggs (5.5 vs 6.0 eggs) at a slower rate (0.90 eggs day–1vs 0.95 eggs day–1). These temperature-related declines in reproductive output were accompanied by decreases in modal (from 36.6 at 21°C to 24.3 nm at 7°C) and median very low density lipoprotein (VLDL) particle diameter (from 29.6 to 26.4 nm) and in the proportion of VLDL particles that were capable of passing through the pores in the ovary to access the developing ovarian follicles (i.e. particles with diameters between 25 and 44 nm; from 45.90% to 32.55%). However, variation in reproductive output was not related to any static concentration or structural measure of VLDL. Therefore,other temperature-dependent mechanisms must be involved in the physiological processes that regulate reproductive output of passerine birds at low ambient temperatures.
The aerodynamic benefit of wing–wing interaction depends on stroke trajectory in flapping insect wings
Authors: Lehmann Fritz-Olaf , Pick Simon
Published: March 2007

Flying insects may enhance their flight force production by contralateral wing interaction during dorsal stroke reversal (`clap-and-fling'). In this study, we explored the forces and moments due to clap-and-fling at various wing tip trajectories, employing a dynamically scaled electromechanical flapping device. The 17 tested bio-inspired kinematic patterns were identical in stroke amplitude, stroke frequency and angle of attack with respect to the horizontal stroke plane but varied in heaving motion. Clap-and-fling induced vertical force augmentation significantly decreased with increasing vertical force production averaged over the entire stroke cycle, whereas total force augmentation was independent from changes in force produced by a single wing. Vertical force augmentation was also largely independent of forces produced due to wing rotation at the stroke reversals, the sum of rotational circulation and wake capture force. We obtained maximum (17.4%) and minimum(1.4%) vertical force augmentation in two types of figure-eight stroke kinematics whereby rate and direction of heaving motion during fling may explain 58% of the variance in vertical force augmentation. This finding suggests that vertical wing motion distinctly alters the flow regime at the beginning of the downstroke. Using an analytical model, we determined pitching moments acting on an imaginary body of the flapping device from the measured time course of forces, the changes in length of the force vector's moment arm,the position of the centre of mass and body angle. The data show that pitching moments are largely independent from mean vertical force; however,clap-and-fling reinforces mean pitching moments by approximately 21%, compared to the moments produced by a single flapping wing. Pitching moments due to clap-and-fling significantly increase with increasing vertical force augmentation and produce nose-down moments in most of the tested patterns. The analytical model, however, shows that algebraic sign and magnitude of these moments may vary distinctly depending on both body angle and the distance between the wing hinge and the animal's centre of mass. Altogether, the data suggest that the benefit of clap-and-fling wing beat for vertical force enhancement and pitch balance may change with changing heaving motion and thus wing tip trajectory during manoeuvring flight. We hypothesize that these dependencies may have shaped the evolution of wing kinematics in insects that are limited by aerodynamic lift rather than by mechanical power of their flight musculature.
Take-off and landing forces and the evolution of controlled gliding in northern flying squirrelsGlaucomys sabrinus
Authors: Paskins Keith E. , Bowyer Adrian , Megill William M. , Scheibe John S.
Published: March 2007

Flying squirrels are well known for their ability to glide between trees at the top of a forest canopy. We present experimental performance and behavioural evidence that flight in flying squirrels may have evolved out of a need to control landing forces. Northern flying squirrels were filmed jumping from a horizontal branch to a much larger vertical pole. These were both slightly compliant (less than 1.9 mm N–1), and instrumented using strain gauges so that forces could be measured. Take-off and landing forces were both positively correlated with horizontal range between 0.5 and 2.5 m (r=0.355 and r=0.811, respectively, P<0.05), but not significantly different to each other at each range tested. Take-off forces ranged from 1 to 10 bodyweights, and landing forces were between 3 and 10 bodyweights. Glide angles increased rapidly with horizontal range, approaching 45° at 3 m, above which they gradually decreased, suggesting that northern flying squirrels are optimised for long distance travel. We show that northern flying squirrels initiate full gliding posture at ranges of less than 1 m, without landing any higher than an equivalent ballistic projectile. However, this gliding posture enables them to pitch upwards, potentially stalling the wing, and spreads the landing reaction force over all four extended limbs. At steeper approach angles of close to 45°, flying squirrels were unable to pitch up sufficiently and landed forelimbs first, consequently sustaining higher impact forces. We investigate four hypotheses to explain the origin of flight in these animals and conclude that the need to reduce landing impact forces was most likely to have stimulated the development of aerial control in flying squirrels.
The effect of decoupling olfactory and visual stimuli on the foraging behavior ofManduca sexta
Authors: Goyret Joaquín , Markwell Poppy M. , Raguso Robert A.
Published: March 2007

Within an appetitive context, Manduca sexta, a nectivorous nocturnal hawkmoth, can be attracted by a range of stimuli including floral volatiles and visual display, carbon dioxide and water vapor. Several studies on this and other flower-visiting insects have shown how olfactory and visual stimulation play (or do not play) a role in attraction and feeding. Nevertheless, these studies have consistently manipulated stimuli in a`presence–absence' manner. Here, we experimentally decoupled the presentation of both stimuli spatially and temporally in a wind tunnel, rather than entirely eliminating either one, and found that the decision-making process based on these stimuli is more flexible and complex than previously asserted. Manduca sexta was most responsive when both cues were present and emanated from the same source. When stimuli were spatially separated, responsiveness levels were comparable to those elicited by a single stimulus. However, transient olfactory stimulation either before or after visually guided approach (temporal decoupling) enhanced responsiveness to an odorless visual target. Additionally, searching times were increased by either a transient olfactory stimulation before take-off or by having the flower model spatially separated from the odor source tracked by the moths. Finally,in a dual-choice experiment, moths showed a strong bias for the visual display over the odor plume, suggesting the former to be the ultimate indicator of a nectar source. Our manipulation of floral cues shows that the feeding behavior of M. sexta, and probably of other nectivorous insects, is based not only on the sensory stimulation per se but also on the temporal and spatial pattern in which these stimuli are perceived.
Pregnancy block by MHC class I peptides is mediatedviathe production of inositol 1,4,5-trisphosphate in the mouse vomeronasal organ
Authors: Thompson Roger N. , McMillon Ronald , Napier Audrey , Wekesa Kennedy S.
Published: March 2007

The vomeronasal organ (VNO) has evolved to link an animal's behavior to its environment in a highly species-specific fashion. In mice, it is thought to be the primary sensory system responsible for the detection of pheromones. Pheromones regulate a variety of responses including mate recognition in the context of selective pregnancy failure. MHC (major histocompatibility complex)class I peptides have been identified as compounds that elicit the pregnancy block effect via the VNO. However, the transduction cascade of these molecules is unknown and it is not known if the production of these compounds are androgen dependent. By using male urine and MHC peptides, we show that female mice treated with MHC peptides (in urine or PBS) and urine from castrated males or juvenile mice of different haplotypes respond to the Bruce Effect paradigm in a manner equivalent to female mice exposed to whole urine. In addition to providing new evidence that urine from castrated or juvenile males and MHC peptides can induce pregnancy block, we show correlation of the effect with an increase in inositol 1,4,5-trisphosphate.
Parameters influencing the dissolved oxygen in the boundary layer of rainbow trout (Oncorhynchus mykiss) embryos and larvae
Authors: Ciuhandu Cosima S. , Wright Patricia A. , Goldberg Jeffrey I. , Stevens E. Don
Published: March 2007

We investigated the influence of oxygen demand (developmental stage) and supply (hypoxia, water flow rate, the chorion and body movements) on the oxygen concentration within the boundary layer next to the chorion of embryos or skin of larvae of rainbow trout (Oncorhynchus mykiss). Oxygen microelectrodes were used to measure dissolved oxygen (DO) within the boundary layer of trout embryos and larvae. As the embryos and larvae developed, the DO gradient and the thickness of the boundary layer increased. The DO concentration within the boundary layer next to the chorion or skin surface decreased as the DO concentration in the free-stream water decreased. A decrease in water flow rate increased the magnitude of the gradient and thickness of the boundary layer. In normoxia, the DO in the perivitelline fluid inside the chorion was 16±3.0% saturation at 31 days post fertilization, indicating that the chorion was a significant barrier to oxygen diffusion. The number of body movements did not change when embryos were exposed to hypoxia before hatching, but after hatching, hypoxia resulted in a decrease in body movements of the larvae. Taken together, our data indicate that the oxygen boundary layer around trout embryos and larvae depends on both the oxygen demand and supply. The factors that significantly impacted boundary layer oxygen were developmental stage, free-stream oxygen levels, water flow rate, and the presence of the chorion.
Regulation of feeding behaviour and locomotor activity bytakeoutinDrosophila
Authors: Meunier Nicolas , Belgacem Yesser Hadj , Martin Jean-René
Published: March 2007

The hormonal regulation of feeding behaviour is well known in vertebrates,whereas it remains poorly understood in insects. Here, we report that the takeout gene is an essential component of nutritional homeostasis in Drosophila. takeout encodes a putative juvenile hormone (JH)binding protein and has been described as a link between circadian rhythm and feeding behaviour. However, the physiological role of takeout and its putative link to JH remain unknown. In this study, we show that takeout (to1) flies failed to adapt their food intake according to food availability and that most defects could be genetically rescued. When food is abundant, to1 are hyperphagic, yielding to hypertrophy of the fat body. When food reappears after a starvation period, to1 flies do not increase their food intake as much as wild-type flies. This defect in food intake regulation is partly based on the action of Takeout on taste neurons, because the sensitivity of to1 gustatory neurons to sugars does not increase after starvation, as in wild-type neurons. This lack of regulation is also evident at the locomotor activity, which normally increases during starvation, a behaviour related to food foraging. In addition, to1 flies lack sexual dimorphism of locomotor activity,which has previously been linked to the JH circulating level. Moreover,application of the JH analog methoprene rescues the phenotype. These results suggest that takeout plays a central role as a feeding regulator and may act by modulating the circulating JH level.
Social domination increases neuronal survival in the brain of juvenile crayfishProcambarus clarkii
Authors: Song Cha-Kyong , Johnstone Laurel M. , Schmidt Manfred , Derby Charles D. , Edwards Donald H.
Published: March 2007

Olfactory cues are among the sensory inputs that crayfish use in establishing dominance hierarchies. Throughout their lives, new neurons are continuously added into brain cell clusters 9 and 10, which contain somata of olfactory local and projection interneurons, respectively. Using markers for DNA synthesis (bromodeoxyuridine) and mitosis (phospho-histone-3), we tested juvenile crayfish (Procambarus clarkii) to examine effects of pairwise social experience on proliferation and survival of cells in these brain regions. Proliferating and mitotic cells appeared within restricted neurogenic areas in both clusters and in `tails' extending from them. These tails, embedded in tubulin-positive strands, are linked by a patch of cells. Neither cell proliferation nor mitotic activity was affected by social dominance. Cell survival of neuronal precursors was affected by dominance:compared to dominants, subordinates had fewer newborn cells surviving in cluster 9 after 14 days of social experience. Social experience also affected body growth rate, but the effect of social experience on neurogenesis remained when differences in body growth rate were statistically controlled. We conclude that social domination enhances survival of new olfactory interneuronal precursors compared to social subordination but not compared to social isolation.
The role of calcium and magnesium in the concrete tubes of the sandcastle worm
Authors: Sun ChengJun , Fantner Georg E. , Adams Jonathan , Hansma Paul K. , Waite J. Herbert
Published: March 2007

Sandcastle worms Phragmatopoma californica build mound-like reefs by sticking together large numbers of sand grains with cement secreted from the building organ. The cement consists of protein plus substantial amounts of calcium and magnesium, which are not invested in any mineral form. This study examined the effect of calcium and magnesium depletion on the structural and mechanical properties of the cement. Divalent ion removal by chelating with EDTA led to a partial collapse of cement architecture and cement dislodgement from silica surfaces. Mechanical properties examined were sand grain pull-out force, tube resistance to compression and cement adhesive force. EDTA treatment reduced sand grain pull-out forces by 60% and tube compressive strength by 50% relative to controls. EDTA lowered both the maximal adhesive force and energy dissipation of cement by up to an order of magnitude. The adhesiveness of calcium- and magnesium-depleted cement could not be restored by re-exposure to the ions. The results suggest that divalent ions play a complex and multifunctional role in maintaining the structure and stickiness of Phragmatopoma cement.
Development of New Semiconducting Materials for Durable High-performance Air-stable Organic Field-effect Transistors
Authors: Takimiya Kazuo , Kunugi Yoshihito , Otsubo Tetsuo
Published: April 2007

New thiophene- and selenophene-fused aromatic compounds were successfully developed as high-performance semiconducting materials for organic field-effect transistors (OFETs). Among them, the most advanced compounds designed on consideration of structure–function relationship showed durable air-stable FET performance. This article highlights the research strategy and development of these superior compounds as well as the molecular factors for the improvement of mobility, sensitivity, and stability, which are very informative for the design of practical semiconductors.
Perinatal Risk Factors for Hospitalization for Pneumococcal Disease in Childhood: A Population-Based Cohort Study
Authors: Mahon Barbara E. , Ehrenstein Vera , Nørgaard Mette , Pedersen Lars , Rothman Kenneth J. , Sørensen Henrik T.
Published: April 2007

OBJECTIVE. The objective of this study was to examine the relation of factors that are present at birth to subsequent hospitalization for childhood pneumococcal disease.

METHODS. We conducted a cohort study of all singletons born in 3 counties in western Denmark from 1980 through 2001, using population-based registries to obtain data on pregnancy- and birth-related variables and hospitalizations through age 12. We calculated incidence rates of pneumococcal disease hospitalization overall and within strata of study variables and used Poisson regression to estimate rate ratios for pneumococcal disease hospitalization while accounting for other birth characteristics.

RESULTS. Among 338504 eligible births, 1052 children were later hospitalized for pneumococcal disease. Pneumonia accounted for most hospitalizations (81.9%). The pneumococcal disease hospitalization rate was highest among 7- to 24-month-olds, followed by 0- to 6-month-olds and 25- to 60-month-olds. The highest rates, typically over 200 hospitalizations per 100 000 person-years, were in 0- to 6- and 7- to 24-month-old children who were born preterm or with low birth weight, a low 5-minute Apgar score, or birth defects. The hospitalization rate was lower for first-born children at 0 to 6 months but not at older ages. At older ages, hospitalization rates were not substantially different for children whose mothers smoked during pregnancy, but at 0 to 6 months, the rate was higher for children of multiparous nonsmokers than for others. Adjusted rate ratios were elevated across all age categories for several variables, including low birth weight, presence of birth defects, and low 5-minute Apgar. For several others, including preterm birth, maternal multiparity, age ≤20 years, and non-Danish/European Union citizenship, adjusted rate ratios were elevated only for 0- to 6-month-olds.

CONCLUSIONS. This large cohort study of hospitalization for childhood pneumococcal disease clarifies the roles of some gestation and birth factors while raising new questions about how these factors work.
Patient and Hospital Characteristics Associated With Length of Stay and Hospital Charges for Pediatric Sports-Related Injury Hospitalizations in the United States, 2000–2003
Authors: Yang Jingzhen , Peek-Asa Corinne , Allareddy Veerasathpurush , Phillips George , Zhang Ying , Cheng Gang
Published: April 2007

OBJECTIVES. The objectives of this study were to describe the patient and hospital characteristics of pediatric sports injury hospitalization and to determine the hospital characteristics that are associated with length of stay and total hospital charges (per discharge).

METHODS. Children who were aged 5 to 18 years and had a diagnosis of a sports injury in the Nationwide Inpatient Sample between 2000 and 2003 were included. National estimates of pediatric sports injury hospitalization, including the average and median of length of stay and total hospital charges, were computed. The relationship of hospital characteristics to length of stay and total hospital charges were assessed using linear regression, adjusting for patient characteristics and sample weight.

RESULTS. A total of 7979 pediatric sports injury hospitalizations among children who were aged 5 to 18 were identified during 4 years, approximately 10000 per year, nationwide. More than half of the hospitalizations were attributed to fractures. The mean and median of length of stay for pediatric sports injuries was 2.4 and 1.1 days, respectively. When weighted, the estimated total hospital charges for sports injury hospitalizations among 5- to 18-year-olds were $485 million during 4 years, with a steady increase each year. Urban hospitals had 46.1% higher total hospital charges than rural hospitals. Hospitals in the western United States had significantly greater total hospital charges than those in other regions.

CONCLUSIONS. The findings provide an empirical basis for future research on the magnitude of sports-related injuries that result in hospitalization among children. More research is needed to identify contributing factors that are associated with length of stay and total hospital charges for sports injury hospitalization. Intervention efforts also should be directed toward preventing severe sports injuries and to reducing the hospitalization and cost.
Antiviral Therapy and Prophylaxis for Influenza in Children
Authors:   Committee on Infectious Diseases
Published: April 2007

This Clinical Report was retired March 2014.

Antiviral agents are available that are safe and effective for the treatment and prophylaxis of influenza virus infections in children. The neuraminidase inhibitors (oseltamivir [Tamiflu] and zanamivir [Relenza]) are preferred agents because of current widespread resistance to the adamantanes (amantadine [Symmetrel] and rimantadine [Flumadine]). Therapy should be provided to children with influenza infection who are at high risk of severe infection and to children with moderate-to-severe influenza infection who may benefit from a decrease in the duration of symptoms. Prophylaxis should be provided (1) to high-risk children who have not yet received immunization and during the 2 weeks after immunization, (2) to unimmunized family members and health care professionals with close contact with high-risk unimmunized children or infants who are younger than 6 months, and (3) for control of influenza outbreaks in unimmunized staff and children in an institutional setting. Testing of current H5N1 avian influenza virus isolates, the potential agents of pandemic influenza, suggests susceptibility to oseltamivir and zanamivir. Because no prospective data exist on the efficacy of these agents in humans for H5N1 strains, the dosage and duration of therapy in adults and children may differ from those documented to be effective for epidemic influenza strains.
Effects of acid treatment and composting on bones used as fertilizer
Authors: Kovács D. , Kardos G. , Füleky G.
Published: April 2007

The aim of the work was to analyse the compostable properties of bone powder produced via different treatment methods and industrial conditions, and to study their effect on plant growth and phosphorus uptake. The bones were treated in water with different temperatures, bone-water ratios and treatment times. Further treatment was carried out with citric, nitric and sulphuric acid with different concentrations, temperatures, bone-water ratios and treatment times. Industrial bone powder was composted under model industrial conditions.The available phosphorus content of these materials was estimated using ryegrass (
Lolium perenne
) as indicator plant in a climatic chamber.The water-soluble phosphorus content of the bones increased in the citric acid and sulphuric acid treatment, depending on the water treatment conditions and the acid concentration. This increase amounted to about 30 times (0.32–8.51 mg/100 mg) compared to the water treatment.The results of the plant test demonstrated that the phophorus content of treated bone powder and compost was readily available to plants. The phosphorus content of the compost was available over a longer period.
Correlation analysis of yields and related physiological variables in twelve generations of durum wheat
Authors: Sharma S. , Sharma Y.
Published: April 2007

The experimental material comprised three crosses, namely Cocorit 71 × A-9-30-1, HI 8062 × JNK-4W-128 and Raj 911 × DWL 5002, generated from six diverse parents. Twelve populations of each of these three crosses revealed that sufficient genetic variation was recorded among generations for all the traits in three crosses. The results of a correlation study demonstrated that the grain yield per plant was significantly and positively associated with peduncle area and flag leaf area in the cross Cocorit 71 × A-9-30-1. However, the spike area had poor correlation with grain yield. In the cross HI 8062 × JNK-4W-128, grain yield per plant was positively associated with peduncle area and spike area, whereas flag leaf area showed a positive but weak association with grain yield. In the cross Raj 911 × DWL 5002, grain yield per plant was positively associated with all three physiological traits studied, indicating that improvement in grain yield may be made by these traits in this material. Peduncle area appeared to be the most important trait in the present study because of its association with grain yield in all three crosses. Although flag leaf area and spike area showed a positive association with grain yield in all three crosses, their relative magnitudes and significance changed from one cross to the other. Correlation studies revealed that selection for peduncle area would lead to high yield in durum wheat. However, due consideration should also be given to flag leaf area and spike area during the selection of plants for further tangible advances in grain yield in durum owing to their positive association with grain yield.