bluuebunny/crossref_metadata_2025 huggingface dataset:
A pitcher injury risk assessment study analyzing composite, titanium, aluminum and wood softball bat performance
Authors: McDowell Mark , Ciocco Michael V.
Published: November 2006

Over the past few years, there has been a significant increase in the performance of softball bats from the Olympics down to the recreational level. It is theorized that the introduction of composite‐based material bats has been the largest contributor to the increase in batted‐ball performance, which directly corresponds to a decrease in available pitcher reaction time that can lead to an increase in injury potential. To test this theory, a controlled field‐test study comparing all of the different bat model types currently available was conducted. The performance of ten bat model types; two composite‐based, two titanium‐based, two aluminum‐based multi‐wall, two aluminum‐based single‐wall and two wood‐based bats were measured using 1686 N/0.64 cm (379 lbs/0.25”) compression softballs in order to calculate available pitcher reaction times when using a specific bat model type. Over 1000 Batted‐ball velocity measurements were analyzed using two calibrated radar devices and five experienced test subjects. The results of this study indicate that when titanium‐based or composite‐based softball bat performance results are compared to published safety studies in the sports of softball and baseball, available pitcher reaction times are unsafe, which can lead to a higher injury risk potential. The significance of this research is to provide experimental field‐test data on the possible safety risks to pitchers that can be used to reduce the injury potential and promote safety awareness in the sport of softball.
Running performance after adaptation to acutely intermittent hypoxia
Authors: Wood Matthew R. , Dowson Martin N. , Hopkins Will G.
Published: November 2006

To quantify the effects of adaptation to acutely intermittent hypoxia on running performance, we randomized 29 trained male hockey and soccer players in double‐blind fashion to altitude or placebo groups for 15 days of daily use of a functional or placebo hypoxic re‐breathing device. Each day's exposure consisted of alternately breathing stale and fresh air for 6 and 4 min respectively over 1 h. Oxygen saturation was monitored with pulse oximeters and progressively reduced in the hypoxia group (90% on Day 1, 77% on Day 15; equivalent to altitudes of ∼3600–6000 m above sea level). Performance tests were an incremental run to maximum speed followed by six maximal‐effort running sprints; tests were performed 1 day before, 3 days after, and 12 days after the 15‐day treatment. Relative to placebo, at 3 days post treatment the hypoxia group showed a mean increase in maximum speed of 2.0% (90% confidence limits, ±0.5%); sprint speed was relatively faster by 1.5% (±1.7%) in the first sprint through 7.0% (±1.5%) in the last; there were also substantial reductions in exercise lactate concentration and resting and exercise heart rate. Substantial effects on performance were still present 9 days later. Thus, adaptation to acutely intermittent hypoxia substantially improves high‐intensity running performance.
Discriminant analysis of game‐related statistics between basketball guards, forwards and centres in three professional leagues
Authors: Sampaio Jaime , Janeira Manuel , Ibáñez Sergio , Lorenzo Alberto
Published: November 2006

The aim of the present paper was to examine the differences in game‐related statistics between basketball guards, forwards and centres playing in three professional leagues: National Basketball Association (NBA, superior level) in the USA, Associación de Clubs de Baloncesto (ACB, one of the best European leagues) in Spain and Liga de Clubes de Basquetebol (LCB, inferior level) in Portugal. We reasoned that the knowledge of these differences could allow the coaches to better establish and monitor playing patterns and increase the effectiveness of the player recruitment process. Archival data was gathered for the 2000–2001 play‐off final series of the NBA (five games), ACB (three games) and LCB (four games). For players in each league, discriminant analysis was able to identify game‐related statistics that maximized mean differences between playing positions (p<0.05). The interpretation of the obtained discriminant functions was based on examination of the structure coefficients greater than ∣0.30∣. In the LCB league, centres and guards were discriminated mainly in terms of defensive tasks, with emphasis on blocks (structure coefficient, SC=0.35) and defensive rebounds (SC=0.43) and a de‐emphasis on unsuccessful 3‐point field‐goals (SC= − 0.37). In the ACB, centres and guards were discriminated by offensive tasks, with emphasis on assists (SC=0.52) and 3‐point field‐goals, both successful (SC=0.35) and unsuccessful (SC=0.35), and a de‐emphasis on offensive rebounds (SC= − 0.44). Finally, in the NBA league guards and centres were discriminated by offensive tasks, with emphasis on offensive rebounds (SC=0.31) and a de‐emphasis on assists (SC= − 0.37) and unsuccessful 3‐point field‐goals (SC= − 0.34). These three analyses provided high overall percentages of successful classification (86% for the LCB league, 74% for the ACB and 85% for the NBA). Generally, the players’ game‐related statistics varied according to playing position, probably because of the well‐known differences in the players’ anthropometric characteristics that conditioned the distance they play from the basket. Coaches can use these results to reinforce the importance of relying on different players’ contributions to team performance and evaluate players’ game performance according to their playing position. Conversely, these discriminant models could help in player recruitment and improve training programmes.
The surface measure and cone measure on the sphere of ℓ_{𝑝}ⁿ
Authors: Naor Assaf
Published: November 2006

We prove a concentration inequality for the

ℓ
q
n

\ell _q^n

norm on the

ℓ
p
n

\ell _p^n

sphere for

p
,
q
>
0

p,q>0

. This inequality, which generalizes results of Schechtman and Zinn (2000), is used to study the distance between the cone measure and surface measure on the sphere of

ℓ
p
n

\ell _p^n

. In particular, we obtain a significant strengthening of the inequality derived by Naor and Romik (2003), and calculate the precise dependence of the constants that appeared there on

p
p

.
Every real ellipsoid in ℂ² admits CR umbilical points
Authors: Huang Xiaojun , Ji Shanyu
Published: November 2006

We prove that every real ellipsoid

M
⊂

C

2

M\subset \mathbb {C}^2

admits at least four umbilical points, which can be compared to the result of Webster that a generic real ellipsoid in

C

n

\mathbb {C}^n

with

n
≥
3

n\ge 3

does not admit any umbilical point.
On algebraic 𝜎-groups
Authors: Kowalski Piotr , Pillay Anand
Published: November 2006

We introduce the categories of algebraic

σ
\sigma

-varieties and

σ
\sigma

-groups over a difference field

(
K
,
σ
)

(K,\sigma )

. Under a “linearly

σ
\sigma

-closed" assumption on

(
K
,
σ
)

(K,\sigma )

we prove an isotriviality theorem for

σ
\sigma

-groups. This theorem immediately yields the key lemma in a proof of the Manin-Mumford conjecture. The present paper crucially uses ideas of Pilay and Ziegler (2003) but in a model theory free manner. The applications to Manin-Mumford are inspired by Hrushovski’s work (2001) and are also closely related to papers of Pink and Roessler (2002 and 2004).
Polarization of hippocampal neurons with competitive surface stimuli: contact guidance cues are preferred over chemical ligands
Authors: Gomez Natalia , Chen Shaochen , Schmidt Christine E
Published: November 2006

Neuronal behaviour is profoundly influenced by extracellular stimuli in many developmental and regeneration processes. Understanding neuron responses and integration of environmental signals could impact the design of successful therapies for neurodegenerative diseases and nerve injuries. Here, we have investigated the influence of localized extracellular cues on polarization (i.e. axon formation) of hippocampal neurons. Electron-beam lithography, microfabrication techniques and protein immobilization were used to create a unique system that provided simultaneous and independent chemical and physical cues to individual neurons. In particular, we analysed competitive responses between simultaneous stimulation with chemical ligands, including immobilized nerve growth factor and laminin, and contact guidance cues mediated by surface topography (i.e. microchannels). Contact guidance cues were preferred 70% of the time over chemical ligands by neurons extending axons, which suggests a stronger stimulation mechanism triggered by topography. This investigation contributes to the understanding of neuronal behaviour on artificial substrates, which is applicable to the creation of artificial environments for neural engineering applications.
Proteins from extremophiles as stable tools for advanced biotechnological applications of high social interest
Authors: Champdoré Marcella de , Staiano Maria , Rossi Mosè , D'Auria Sabato
Published: November 2006

Extremophiles are micro-organisms adapted to survive in ecological niches defined as ‘extreme’ for humans and characterized by the presence of adverse environmental conditions, such as high or low temperatures, extreme values of pH, high salt concentrations or high pressure. Biomolecules isolated from extremophiles possess extraordinary properties and, in particular, proteins isolated from extremophiles represent unique biomolecules that function under severe conditions, comparable to those prevailing in various industrial processes.

In this article, we will review some examples of recent applications of thermophilic proteins for the development of a new class of fluorescence non-consuming substrate biosensors for monitoring the levels of two analytes of high social interest, such as glucose and sodium.
Little left in the tank: metabolic scaling in marine teleosts and its implications for aerobic scope
Authors: Killen Shaun S , Costa Isabel , Brown Joseph A , Gamperl A. Kurt
Published: November 2006

Fish larvae are the world's smallest vertebrates, and their high rates of mortality may be partially owing to a very limited aerobic scope. Unfortunately, however, no complete empirical dataset exists on the relationship between minimal and maximal metabolism (and thus aerobic scope) for any fish species throughout ontogeny, and thus such an association is hard to delineate. We measured standard and maximal metabolism in three marine fish species over their entire life history, and show that while aerobic scope depends greatly on body size and developmental trajectory, it is extremely small during the early life stages (factorial aerobic scope≤1.5). Our findings strongly suggest that limited scope for aerobic activity early in life is likely to constrain physiological function and ultimately impact behaviour and possibly survival. Furthermore, our results have important implications for ecological models that incorporate metabolic scaling, and provide additional evidence against the existence of ‘universal’ scaling exponents.
Plants use macronutrients accumulated in leaf-cutting ant nests
Authors: Sternberg Leonel da S.L , Pinzon Maria Camila , Moreira Marcelo Z , Moutinho Paulo , Rojas Enith I , Herre Edward Allen
Published: November 2006

Leaf-cutting ants (
Atta
spp.) are known for their extensive defoliation in neo-tropical forests and savannahs. Debate about the costs and benefits of their activities has been largely dominated by their detrimental effects on agriculture and agroforestry. However, the large accumulation of nutrients and changes in soil properties near their nests might benefit plants growing near them. Here, we test whether trees use nutrients that accumulate in debris piles near, or refuse chambers within, leaf-cutting ant nests. At two tropical sites (a moist tropical forest site in Panama and a savannah site in Brazil), we fed leaves labelled with the stable isotope
15
N to two species of leaf-cutting ants (
Atta colombica
and
Atta laevigata
) and traced the stable isotope label in plants surrounding the two nests. Thus, we show that plants in both sites access resources associated with
Atta
nests. In addition, leaf tissue of trees near the nests labelled with
15
N had significantly higher calcium concentrations than those of distal, unlabelled conspecifics. It has been documented that calcium is a limiting macronutrient in tropical forests and savannahs.
Atta
may thus play an important ecological role through their long-distance transport, redistribution and concentration of critical macronutrients.
Insect walking is based on a decentralized architecture revealing a simple and robust controller
Authors: Cruse Holk , Dürr Volker , Schmitz Josef
Published: November 2006

Control of walking in rugged terrain requires one to incorporate different issues, such as the mechanical properties of legs and muscles, the neuronal control structures for the single leg, the mechanics and neuronal control structures for the coordination between legs, as well as central decisions that are based on external information and on internal states.

Walking in predictable environments and fast running, to a large degree, rely on muscle mechanics. Conversely, slow walking in unpredictable terrain, e.g. climbing in rugged structures, has to rely on neuronal systems that monitor and intelligently react to specific properties of the environment. An arthropod model system that shows the latter abilities is the stick insect, based on which this review will be focused.

An insect, when moving its six legs, has to control 18 joints, three per leg, and therefore has to control 18 degrees of freedom (d.f.). As the body position in space is determined by 6 d.f. only, there are 12 d.f. open to be selected. Therefore, a fundamental problem is as to how these extra d.f. are controlled. Based mainly on behavioural experiments and simulation studies, but also including neurophysiological results, the following control structures have been revealed. Legs act as basically independent systems. The quasi-rhythmic movement of the individual leg can be described to result from a structure that exploits mechanical coupling of the legs via the ground and the body. Furthermore, neuronally mediated influences act locally between neighbouring legs, leading to the emergence of insect-type gaits. The underlying controller can be described as a free gait controller. Cooperation of the legs being in stance mode is assumed to be based on mechanical coupling plus local positive feedback controllers. These controllers, acting on individual leg joints, transform a passive displacement of a joint into an active movement, generating synergistic assistance reflexes in all mechanically coupled joints. This architecture is summarized in the form of the artificial neural network,Walknet, that is heavily dependent on sensory feedback at the proprioceptive level. Exteroceptive feedback is exploited for global decisions, such as the walking direction and velocity.
Rhomboid proteins: conserved membrane proteases with divergent biological functions
Authors: Urban Sinisa
Published: November 2006

The rhomboid gene was discovered in Drosophila, where it encodes a seven transmembrane protein that is the signal-generating component of epidermal growth factor (EGF) receptor signaling during development. Although metazoan developmental regulators are rarely conserved outside the animal kingdom, rhomboid proteins are conserved in all kingdoms of life, but the significance of this remains unclear. Recent biochemical reconstitution and high-resolution crystal structures have provided proof that rhomboid proteins function as novel intramembrane proteases, with a serine protease-like catalytic apparatus embedded within the membrane bilayer, buried in a hydrophilic cavity formed by a protein ring. A thorough consideration of all known examples of rhomboid function suggests that, despite biochemical similarity in mechanism and specificity, rhomboid proteins function in diverse processes including quorum sensing in bacteria, mitochondrial membrane fusion, apoptosis, and stem cell differentiation in eukaryotes; rhomboid proteins are also now starting to be linked to human disease, including early-onset blindness, diabetes, and parasitic diseases. Regulating cell signaling is at the heart of rhomboid protein function in many, but not all, of these processes. Further study of these novel enzymes promises to reveal the evolutionary path of rhomboid protein function, which could provide insights into the forces that drive the molecular evolution of regulatory mechanisms.
MtHAP2-1 is a key transcriptional regulator of symbiotic nodule development regulated by microRNA169 in Medicago truncatula
Authors: Combier Jean-Philippe , Frugier Florian , de Billy Françoise , Boualem Adnane , El-Yahyaoui Fikri , Moreau Sandra , Vernié Tatiana , Ott Thomas , Gamas Pascal , Crespi Martin , Niebel Andreas
Published: November 2006

In the model legume Medicago truncatula, we identified a new transcription factor of the CCAAT-binding family, MtHAP2-1, for which RNA interference (RNAi) and in situ hybridization experiments indicate a key role during nodule development, possibly by controlling nodule meristem function. We could also show that MtHAP2-1 is regulated by microRNA169, whose overexpression leads to the same nodule developmental block as MtHAP2-1 RNAi constructs. The complementary expression pattern of miR169 and MtHAP2-1 and the phenotype of miR169-resistant MtHAP2-1 nodules strongly suggest, in addition, that the miR169-mediated restriction of MtHAP2-1 expression to the nodule meristematic zone is essential for the differentiation of nodule cells.
Combination chemotherapy followed by autologous stem cell transplant for enteropathy‐associated T cell lymphoma
Authors: Bishton Mark J. , Haynes Andrew P.
Published: November 2006

Enteropathy‐associated T cell lymphoma (EATL) is a rare entity associated with coeliac disease, with a poor prognosis due to perforation and gastro‐intestinal bleeding during treatment, and a high relapse risk. Six patients were treated with two cycles of IVE (ifosphamide, etoposide, epirubicin), followed by two cycles of high‐dose methotrexate (3 g/m2) with folinic acid rescue and a BEAM (carmustine, etoposide, cytarabine, melphalan) autograft. Enteral feeding was given throughout treatment. Four patients remain alive in complete remission at 1·83–4·32 years; two have relapsed. Given the historically poor outcome in these patients, this regimen appears very promising in the treatment of EATL.
Trinucleotide repeat dynamic mutation identifying susceptibility in familial and sporadic chronic lymphocytic leukaemia
Authors: Auer Rebecca L. , Dighiero Guillaume , Goldin Lynn R. , Syndercombe‐Court Denise , Jones Christopher , McElwaine Suzanne , Newland Adrian C. , Fegan Christopher D. , Caporaso Neil , Cotter Finbarr E.
Published: November 2006

Chronic lymphocytic leukaemia (CLL) has a strong hereditary component, but an understanding of predisposition genes is poor. Anticipation with familial CLL has been reported, although the molecular mechanism is unknown. Expansion of trinucleotide repeat sequences underlies anticipation observed in neurodegenerative disease. A polymerase chain reaction‐based assay was used to analyse the stability of ten CCG‐ and CAG‐trinucleotide repeat tracts in 18 CLL families and 140 patients with the sporadic form of the disease. The study suggests that anticipation, if it occurs in CLL, is not linked to CCG‐ and CAG‐repeat expansion, however, variation in repeat length at certain loci (FRA16A) may permit identification of susceptible family members. In addition, polymorphisms with prognostic significance were identified. These were high length (but not expanded) repeats at FRA11B (P = 0·01), ATXN1 (P = 0·032) and ATXN3 (P = 0·022), all associated with poor risk disease.
Altered expression of the tetraspanin CD81 on B and T lymphocytes during HIV-1 infection
Authors: Meroni L , Milazzo L , Menzaghi B , Mazzucchelli R , Mologni D , Morelli P , Broggini V , Adorni F , Galli M , Riva A
Published: November 2006

CD81 is a member of the tetraspan superfamily and plays a role in immune responses and in hepatitis C virus (HCV) pathogenesis. We analysed CD81 cell surface and mRNA expression in different lymphocytic subpopulations in human immunodeficiency virus (HIV)-1, HCV and dually infected subjects. CD81 cell surface expression was evaluated with fluorescence activated cell sorter (FACS) analysis; mRNA quantification was performed with semiquantitative polymerase chain reaction (PCR). CD81 cell surface expression on CD4+ T lymphocytes was significantly different by analysis of variance (anova) test (P < 0·001), with reduced expression in HIV-1+ patients. In B lymphocytes, higher cell surface expression was present in HIV-1, in HCV and in dually infected subjects compared to healthy controls. CD81 expression on B lymphocytes showed a positive correlation with plasma HIV-RNA. CD81 mRNA levels in B lymphocytes were significantly higher in HIV-1+ patients compared to healthy controls. The potential consequence of the down-regulation of CD81 in CD4+ cells during HIV-1 infection in conjunction with diverted CD28, CD4 and CD3 expression is the disruption of T cell function. Increased CD81 expression on B lymphocytes might explain the higher prevalence of lymphoproliferative disorders in HIV-1 and HCV infection. Up-regulation of CD81 mRNA on CD4+ T cells indicates that down-regulation of CD81 occurs at the post-transcriptional/translational level.
IL-10 produced by CD4+ and CD8+ T cells emerge as a putative immunoregulatory mechanism to counterbalance the monocyte-derived TNF-α and guarantee asymptomatic clinical status during chronic HTLV-I infection
Authors: Brito-Melo G E A , Peruhype-Magalhães V , Teixeira-Carvalho A , Barbosa-Stancioli E F , Carneiro-Proietti A B F , Catalan-Soares B , Ribas J G ,   GIPH, Martins-Filho O A
Published: November 2006

Although it is believed widely that distinct patterns of the host immune response are associated with the outcome of chronic human T cell lymphotropic virus type 1 (HTLV-I) infection toward asymptomatic or symptomatic neurodegenerative myelopathy (HAM/TSP), the exact mechanism underlying these immunological events still remains unknown. In this study, we have evaluated the cytokine pattern [interleukin (IL)-12, interferon (IFN)-γ, tumour necrosis factor (TNF)-α, IL-4 and IL-10] of innate and adaptive immunity cells present at the peripheral blood from non-infected (NI) and HTLV-I infected individuals [asymptomatic (AS), oligosymptomatic (OL) and HAM/TSP-HT], following in vitro short-term incubation in the absence/presence of phorbol myristate acetate (PMA) pan-leucocyte stimulation. In the absence of PMA stimulation, our data demonstrate that despite the overall immunological profile of AS mimicry that observed for NI, the high frequency of IL-12+ neutrophils and TNF-α+ monocytes are also a hallmark of this group of individuals. However, the outstanding positive correlation between the high frequency of TNF-α+ monocytes and high levels CD4+ IL-10+ and CD8+ IL-10+ T cells suggests the establishment of immunoregulatory mechanisms that guarantee their asymptomatic clinical status. On the other hand, OL and HT did not present any association between the high frequency and TNF-α+ neutrophils and monocytes and this immunoregulatory profile at their adaptive immunity cells. Upon PMA-index analysis, high levels of type 1 CD4+ T cells, as well as higher IFN-γ/IL-10 and TNF-α/IL-10 ratios, were observed in HT, and re-emphasize the role of Th1-cytokines from CD4+ cells to HTLV-I immunity and disease. Moreover, increasing frequency of CD8+ IFN-γ+ and CD8+ TNF-α+ cells were observed in the HT, which corroborates the marked inflammatory profile underlying this pathological condition and the role of CD8+ T cells in the pathogenesis of HAM/TSP.
The role of desmopressin in bilateral and simultaneous inferior petrosal sinus sampling for differential diagnosis of ACTH‐dependent Cushing's syndrome
Authors: Machado Marcio Carlos , De Sa Sandra Valeria , Domenice Sorahia , Fragoso Maria Candida B. Villares , Puglia Paulo , Pereira Maria Adelaide Albergaria , De Mendonça Berenice Bilharinho , Salgado Luiz Roberto
Published: November 2006

Objective   Bilateral inferior petrosal sinus sampling (BIPSS) with corticotrophin‐releasing hormone (CRH) stimulation is currently the gold standard test for the differential diagnosis of ACTH‐dependent Cushing's syndrome. Reports on the use of desmopressin in this approach are limited. The aim of this study was to evaluate the use of desmopressin during BIPSS in a cohort of patients with ACTH‐dependent Cushing's syndrome.

Design   A retrospective case‐record study.

Patients   Fifty‐six patients with confirmed ACTH‐dependent Cushing's syndrome underwent BIPSS with desmopressin stimulation when presenting negative pituitary tumour imaging.

Measurements   Central to peripheral (CEN:PER) ACTH gradient, lateralization of the ACTH source and surgical tumour confirmation were evaluated.

Results   A CEN:PER ACTH gradient was found in 40 patients under basal conditions (CEN:PER ≥ 2) and in 47 patients after desmopressin stimulation (CEN:PER ≥ 3). Ectopic ACTH‐producing tumours (three lung carcinoid tumour, one thymus carcinoid tumour and one thymus hyperplasia) were confirmed in five out of nine patients without the CEN:PER ACTH gradient, and four cases were false negative for Cushing's disease. Lateralization (IPS:IPS ≥ 1·4) was observed in 80·8% of patients under basal conditions (38/47) and in 97·8% after desmopressin (46/47), and it was surgically confirmed in 78·7%. There were no false‐positive cases. Sensitivity and specificity were 92·1% and 100%, respectively.

Conclusions   Desmopressin improves the differential diagnosis of ACTH‐dependent Cushing's syndrome by amplifying the CEN:PER and IPS:IPS ACTH gradients, and is therefore a useful ACTH secretagogue in BIPSS.
Ultraviolet B screening potential is higher in two cosmopolitan moss species than in a co‐occurring Antarctic endemic moss: implications of continuing ozone depletion
Authors: DUNN JODIE L. , ROBINSON SHARON A.
Published: November 2006

Concentrations of UVB (ultraviolet B) absorbing pigments and anthocyanins were measured in three moss species, over a summer growing season in Antarctica. Pigment concentrations were compared with a range of climatic variables to determine if there was evidence that pigments were induced by UVB radiation, or other environmental parameters, and secondly if there were differences between species in their pigment responses. Significant seasonal differences in the potential UVB screening pigments were found, with the two cosmopolitan species Bryum pseudotriquetrum and Ceratodon purpureus appearing better protected from the potentially damaging effects of ozone depletion than the Antarctic endemic Schistidium antarctici. B. pseudotriquetrum accumulated the highest concentration of UVB screening pigments and showed positive associations between UVB radiation and both UVB absorbing and anthocyanin pigments. The negative associations between water availability measures and UVB absorbing and anthocyanin pigments also suggest that B. pseudotriquetrum is well protected in the desiccated state. This could offer B. pseudotriquetrum an advantage over the other species when high UVB radiation coincides with low temperatures and low water availability, thus limiting physiological activity and consequently, active photoprotective and repair mechanisms. As these pigments could act as either direct UVB screens or antioxidants, the results suggest that B. pseudotriquetrum is best equipped to deal with the negative effects of increased exposure to UVB radiation due to ozone depletion. The most exposed species, C. purpureus, has intermediate and stable concentrations of UVB absorbing pigments suggesting it may rely on constitutive UVB screens. Anthocyanin pigments were more responsive in this species and could offer increased antioxidant protection during periods of high UVB radiation. S. antarctici appears poorly protected and showed no evidence of any UV photoprotective response, providing additional evidence that this endemic is more vulnerable to climate change.
Habitual snoring is associated with elevated hemoglobin A1c levels in non‐obese middle‐aged adults
Authors: JOO SOONJAE , LEE SEUNGMIN , CHOI HUIMAHN A. , KIM JINKWAN , KIM EUNHEE , KIMM KUCHAN , KIM JEHYEONG , SHIN CHOL
Published: November 2006

Hemoglobin A1c (HbA1c) is an indicator of long‐term glycemic control. The purpose of this study was to determine whether habitual snoring is associated with increased HbA1c levels in non‐obese and normoglycemic middle‐aged men and women. A total of 6981 subjects (3362 men and 3619 women) aged 40–69 years from the Korean Health and Genome Study were examined for the study. Each participant received a comprehensive physical examination as well as a set of questions pertaining to demographic characteristics and snoring frequency. Habitual snoring was defined as a snoring frequency of ≥4 days week−1. After adjusting for age, abdominal obesity, and other confounding covariates, male habitual snorers showed a 1.69‐fold excess [95% confidence interval (CI) 1.30–2.19] odds of having a high HbA1c level. Similarly, premenopausal women with habitual snoring had a 2.31 times (95% CI 1.22–4.39) significantly higher odds of having elevated HbA1clevels compared with non‐snorers. This association was not found in postmenopausal women. Multivariate analysis revealed that male habitual snorers aged 40–50 had a 2.08‐fold excess (95% CI 1.40–3.09) risk of having an elevated HbA1c level. In male habitual snores over 50, the strength of association was attenuated. Our findings based on cross‐sectional data support a hypothesis that habitual snoring is associated with impaired glucose tolerance even in non‐obese and normoglycemic men and premenopausal women. However, as waist circumference as an index of abdominal obesity (visceral adiposity) in the present study may only partially represent the effect of visceral fat, there may be a residual confounding from visceral obesity in our result. Longitudinal follow‐up studies are necessary to confirm the association between sleep‐disordered breathing and impaired glucose tolerance and to examine the causal relationship in a healthy population without obesity and diabetes.
Age and individual variability in performance during sleep restriction
Authors: BLIESE PAUL D. , WESENSTEN NANCY J. , BALKIN THOMAS J.
Published: November 2006

The effect of sleep loss on reaction time (RT) performance varies as a function of age, with RTs of older subjects typically showing less decrement (relative to rested baseline) than those of younger subjects. In the current paper, we examined the nature of this relationship in a 7‐day sleep restriction study. The number of repeated measures made it possible to model both intra‐individual trajectories over days and individual differences in these trajectories. Results revealed (a) consistent individual differences in RT patterns over time after controlling for experimental design effects; (b) less cumulative RT decline among older individuals regardless of the degree of sleep restriction; and (c) consistent individual variability in performance patterns even after accounting for the effects of age.
Temazepam at high altitude reduces periodic breathing without impairing next‐day performance: a randomized cross‐over double‐blind study
Authors: NICKOL ANNABEL H. , LEVERMENT JULIETTE , RICHARDS PAUL , SEAL PHILIPPA , HARRIS GREG A. , CLELAND JENIFER , DUBOWITZ GERALD , COLLIER DAVID J. , MILLEDGE JAMES , STRADLING JOHN R. , MORRELL MARY J.
Published: November 2006

The aim of the study was to examine the efficacy and safety of temazepam on nocturnal oxygenation and next‐day performance at altitude. A double‐blind, randomized, cross‐over trial was performed in Thirty‐three healthy volunteers. Volunteers took 10 mg of temazepam and placebo in random order on two successive nights soon after arrival at 5000 m, following a 17‐day trek from 410 m. Overnight SaO2 and body movements, and next‐day reaction time, maintenance of wakefulness and cognition were assessed. Compared with placebo, temazepam resulted in a reduction in periodic breathing from a median (range) of 16 (0–81.3)% of the night to 9.4 (0–79.6)% (P = 0.016, Wilcoxon's signed‐rank test), associated with a small but significant decrease in mean nocturnal SaO2 from 78 (65–84)% to 76 (64–83)% (P = 0.013). There was no change in sleep latency (P = 0.40) or restlessness (P = 0.30). Temazepam had no adverse effect on next‐day reaction time [241 (201–380) ms postplacebo and 242 (204–386) ms post‐temazepam], maintenance of wakefulness (seven trekkers failed to maintain 40 min of wakefulness postplacebo, and four post‐temazepam), cognition or acute mountain sickness. At high altitude temazepam reduces periodic breathing during sleep without an adverse effect on next‐day reaction time, maintenance of wakefulness or cognition. The 2% reduction in mean SaO2 post‐temazepam is likely to be predominantly because of acclimatization, as by chance more trekkers took temazepam on the first night (19 versus 14). We conclude that at high altitude temazepam is effective in reducing periodic breathing, and is safe to use, without any adverse effect upon next‐day performance.
Interaction between FtsW and penicillin‐binding protein 3 (PBP3) directs PBP3 to mid‐cell, controls cell septation and mediates the formation of a trimeric complex involving FtsZ, FtsW and PBP3 in mycobacteria
Authors: Datta Pratik , Dasgupta Arunava , Singh Anil Kumar , Mukherjee Partha , Kundu Manikuntala , Basu Joyoti
Published: November 2006

In bacteria, biogenesis of cell wall at the division site requires penicillin‐binding protein 3 (PBP3) (or FtsI). Using pull‐down, bacterial two‐hybrid, and peptide‐based interaction assays, we provide evidence that FtsW of Mycobacterium tuberculosis (FtsWMTB) interacts with PBP3 through two extracytoplasmic loops. Pro306 in the larger loop and Pro386 in the smaller loop of FtsW are crucial for these interactions. Fluorescence microscopy shows that conditional silencing of ftsW in Mycobacterium smegmatis prevents cell septation and positioning of PBP3 at mid‐cell. Pull‐down assays and conditional depletion of FtsW in M. smegmatis provide evidence that FtsZ, FtsW and PBP3 of mycobacteria are capable of forming a ternary complex, with FtsW acting as a bridging molecule. Bacterial three‐hybrid analysis suggests that in M. tuberculosis, the interaction (unique to mycobacteria) of FtsZ with the cytosolic C‐tail of FtsW strengthens the interaction of FtsW with PBP3. ftsW of M. smegmatis could be replaced by ftsW of M. tuberculosis. FtsWMTB could support formation of the FtsZ–FtsW–PBP3 ternary complex in M. smegmatis. Our findings raise the possibility that in the genus Mycobacterium binding of FtsZ to the C‐tail of FtsW may modulate its interactions with PBP3, thereby potentially regulating septal peptidoglycan biogenesis.
The FOX hunting system: an alternative gain‐of‐function gene hunting technique
Authors: Ichikawa Takanari , Nakazawa Miki , Kawashima Mika , Iizumi Haruko , Kuroda Hirofumi , Kondou Youichi , Tsuhara Yumi , Suzuki Kumiko , Ishikawa Akie , Seki Motoaki , Fujita Miki , Motohashi Reiko , Nagata Noriko , Takagi Tomoko , Shinozaki Kazuo , Matsui Minami
Published: November 2006

We have developed a novel gain‐of‐function system that we have named the FOX hunting system (Full‐length cDNA Over‐eXpressing gene hunting system). We used normalized full‐length cDNA and introduced each cDNA into Arabidopsis by in planta transformation. About 10 000 independent full‐length Arabidopsis cDNAs were expressed independently under the CaMV 35S promoter in Arabidopsis. Each transgenic Arabidopsis contained on average 2.6 cDNA clones and was monitored under various categories such as morphological changes, fertility and leaf color. We found 1487 possible morphological mutants from 15 547 transformants. When 115 pale green T1 mutants were analyzed, 59 lines represented the mutant phenotypes in more than 50% of the T2 progeny. Characterization of two leaf color mutants revealed the significance of this approach. We also document mutants from several categories and their corresponding full‐length cDNAs.
Analysis of calcium spiking using a cameleon calcium sensor reveals that nodulation gene expression is regulated by calcium spike number and the developmental status of the cell
Authors: Miwa Hiroki , Sun Jongho , Oldroyd Giles E. D. , Allan Downie J.
Published: November 2006

Rhizobium‐made Nod factors induce rapid changes in both Ca2+ and gene expression. Mutations and inhibitors that abolish Nod‐factor‐induced Ca2+ spiking block gene induction, indicating a specific role for Ca2+ spiking in signal transduction. We used transgenic Medicago truncatula expressing a ‘cameleon’ Ca2+ sensor to assess the relationship between Nod‐factor‐induced Ca2+ spiking and the activation of downstream gene expression. In contrast to ENOD11 induction, Ca2+ spiking is activated in all root‐hair cells and in epidermal or pre‐emergent root hairs cells in the root tip region. Furthermore, cortical cells immediately below the epidermal layer also show slow Ca2+ spiking and these cells lack Nod‐factor‐induced ENOD11 expression. This indicates a specialization in nodulation gene induction downstream of Nod‐factor perception and signal transduction. There was a gradient in the frequency of Ca2+ spiking along the root, with younger root‐hair cells having a longer period between spikes than older root hairs. Using a Ca2+‐pump inhibitor to block Ca2+ spiking at various times after addition of Nod factor, we conclude that about 36 consecutive Ca2+ spikes are sufficient to induce ENOD11–GUS expression in root hairs. To determine if the length of time of Ca2+ spiking or the number of Ca2+ spikes is more critical for Nod‐factor‐induced ENOD11 expression, jasmonic acid (JA) was added to reduce the rate of Nod‐factor‐induced Ca2+ spiking. This revealed that even when the period between Ca2+ spikes was extended, an equivalent number of Ca2+ spikes were required for the induction of ENOD11. However, this JA treatment did not affect the spatial patterning of ENOD11–GUS expression suggesting that although a minimal number of Ca2+ spikes are required for Nod‐factor‐induced gene expression, other factors restrict the expression of ENOD11 to a subset of responding cells.
Co‐expression of the stress‐inducible zinc finger homeodomain ZFHD1 and NAC transcription factors enhances expression of the ERD1 gene in Arabidopsis
Authors: Tran Lam‐Son Phan , Nakashima Kazuo , Sakuma Yoh , Osakabe Yuriko , Qin Feng , Simpson Sean D. , Maruyama Kyonoshin , Fujita Yasunari , Shinozaki Kazuo , Yamaguchi‐Shinozaki Kazuko
Published: November 2006

The ZFHD recognition sequence (ZFHDRS) and NAC recognition sequence (NACRS) play an important role in the dehydration‐inducible expression of the Arabidopsisthaliana EARLY RESPONSIVETO DEHYDRATION STRESS 1 (ERD1) gene. Using the yeast one‐hybrid system, we isolated a cDNA encoding the ZFHD1 transcriptional activator that specifically binds to the 62 bp promoter region of ERD1, which contains the ZFHDRS. Both in vitro and in vivo analyses confirmed specific binding of the ZFHD1 to ZFHDRS, and the expression of ZFHD1 was induced by drought, high salinity and abscisic acid. The DNA‐binding and activation domains of ZFHD1 were localized on the C‐terminal homeodomain and N‐terminal zinc finger domain, respectively. Microarray analysis of transgenic plants over‐expressing ZFHD1 revealed that several stress‐inducible genes were upregulated in the transgenic plants. Transgenic plants exhibited a smaller morphological phenotype and had a significant improvement of drought stress tolerance. Using the yeast two‐hybrid system, we detected an interaction between ZFHD1 and NACRS‐binding NAC proteins. Moreover, co‐over‐expression of the ZFHD1 and NAC genes restored the morphological phenotype of the transgenic plants to a near wild‐type state and enhanced expression of ERD1 in both Arabidopsis T87 protoplasts and transgenic Arabidopsis plants.
Polymorphisms of the Bcl‐2 family member bfl‐1 in children with atopic dermatitis
Authors: Gray Andrew , Stewart Helen , Pravica Vera , Fryer Anthony A. , Lenney Warren , Hutchinson Ian V. , Arkwright Peter D.
Published: November 2006

T lymphocytes accumulating in the skin of patients with atopic dermatitis (AD) have a prolonged survival and are key mediators of this inflammatory disease. The anti‐apoptotic bfl‐1 gene is unique in that it is the only member of the Bcl‐2 family that is transcriptionally regulated by inflammatory cytokines and might therefore be important in promoting the survival of effector T cells in patients with AD. The aim of this study was to determine whether polymorphisms in the bfl‐1 gene are associated with a predisposition to childhood AD. Four bfl‐1 gene, single nucleotide polymorphisms (SNPs) were studied by ARMS‐PCR in 105 Caucasian children with moderately severe AD and 110 non‐atopic adult controls. In addition to the known polymorphisms of exon 1 (+141*A/G, +202*G/T, +303*A/G), we described a novel polymorphism in the promoter region of the gene (−1182*G/C). We found a significant difference in bfl‐1 +141 genotype [OR (95% CI) 5.1 (1.0–25.2)], as well as bfl‐1−1182:+141:+202:+303 G:A:G:A/G:A:G:A diplotype frequencies [3.5 (1.0–12.2)] in AD (p < 0.05). The study thus provides evidence for an association between bfl‐1 polymorphisms and the genetic predisposition to AD.
Comparison of structural damage caused by Russian wheat aphid (Diuraphis noxia) and Bird cherry‐oat aphid (Rhopalosiphum padi) in a susceptible barley cultivar, Hordeum vulgare cv. Clipper
Authors: Saheed Sefiu Adekilekun , Botha Christiaan Edward Johannes , Liu Lin , Jonsson Lisbeth
Published: November 2006

The Russian wheat aphid (RWA, (Diuraphis noxia) and the Bird cherry‐oat aphid (BCA, (Rhopalosiphum padi L.) cause severe damage to grain crops, including barley. An investigation of the effects of these aphids on a susceptible cultivar revealed that BCA‐infested barley plants remained healthy looking for 2 weeks after feeding commenced. In contrast, signs of stress and damage, including chlorosis and leaf necrosis were evident in RWA‐infested plants. Our study suggests that damage to the vascular tissue because of sustained feeding by BCA was not as extensive as that caused by RWA. In addition, there is a marked difference in the salivary secretion pattern within xylem elements punctured by aphids tapping the xylem for water. RWA deposit electron‐dense, amorphous to smooth saliva, which completely encases the inner walls of affected elements, and saliva encases pit membranes between xylem elements, and between xylem vessels and xylem parenchyma. Xylem tapped by BCA contained more granular saliva, which apparently does not occlude vessel wall apertures or the pit membranes to the same extent, as was observed with RWA. Damage to phloem tissue, including phloem parenchyma elements, sieve tube–companion cell (CC–ST) complexes as well as thick‐walled ST, was extensive. Plasmodesmata between phloem parenchyma elements as well as pore plasmodesmata between the CC and ST were occluded by callose. We conclude that severe, perhaps permanent damage to conducting elements in RWA‐infested leaves may be responsible for the detrimental chlorosis and necrosis symptoms. These symptoms are absent in BCA‐infested plants.
The significance of Arabidopsis AAA proteases for activity and assembly/stability of mitochondrial OXPHOS complexes
Authors: Marta Kolodziejczak , Marta Gibala , Adam Urantowka , Hanna Janska
Published: November 2006

The Arabidopsis genome encodes four mitochondrially localized adenosine 5′‐triphosphate‐dependent metalloproteases called FtsH or AAA proteases. All of them span the inner mitochondrial membrane but the catalytic site of two of them (AtFtsH4 and AtFtsH11) faces the intermembrane space, while AtFtsH3 and AtFtsH10 face the matrix. We used a combination of blue‐native polyacrylamide gel electrophoresis and histochemical staining to reveal the consequences of the loss of one of mitochondrial FtsHs on the efficiency of the oxidative phosphorylation system in Arabidopsis mitochondria. To address this issue, we have selected homozygous lines of respective transferred DNA (T‐DNA) insertional mutants. A decrease in the activity of complexes I and V but not complex IV was observed in the ftsh mutants, except for the mutant lacking functional FtsH11. The reduced activity of complexes I and V was well correlated with a decreased protein level of these complexes. Western blots experiments using specific antibodies against complex V subunits showed a significant reduction of these subunits only in the ftsh4 mutant. Taken together, our results reveal a role of FtsH3, FtsH4 and FtsH10 proteases in the biogenesis of a plant oxidative phosphorylation system.
The transfer of a gene conferring resistance to scald (Rhynchosporium secalis) from Hordeum bulbosum into H. vulgare chromosome 4HS
Authors: Pickering R. , Ruge‐Wehling B. , Johnston P. A. , Schweizer G. , Ackermann P. , Wehling P.
Published: November 2006

Scald is a serious foliar disease that infects barley (Hordeum vulgare L.) causing reduced yields and adversely affecting quality. A means to combat the disease is to breed cultivars that possess genetic resistance. However, all known resistance alleles have so far originated from within the primary genepool of barley. This reliance on H. vulgare and H. vulgare ssp. spontaneum as resistance sources may encourage virulent forms of the pathogen to become established. To broaden the genetic base of cultivated barley and provide novel resistances to many diseases we have used a species from the secondary genepool of barley, H. bulbosum, in a resistance‐breeding programme. In this study we describe the development and trialling of a scald‐resistant recombinant line derived from a hybrid between H. vulgare and H. bulbosum. The scald resistance is simply inherited and located on the short arm of barley chromosome 4 (4HS).
QTL analysis of quality traits in the spring wheat cross RL4452 × ‘AC Domain’
Authors: McCartney C. A. , Somers D. J. , Lukow O. , Ames N. , Noll J. , Cloutier S. , Humphreys D. G. , McCallum B. D.
Published: November 2006

Wheat grain quality is a complex group of traits of tremendous importance to wheat producers, end‐users and breeders. Quantitative trait locus (QTL) analysis studied the genetics of milling, mixograph, farinograph, baking, starch and noodle colour traits in the spring wheat population RL4452/‘AC Domain’. Forty‐seven traits were measured on the population and 99 QTLs were detected over 18 chromosomes for 41 quality traits. Forty‐four of these QTLs mapped to three major QTL clusters on chromosomes 1B, 4D, and 7D. Fourteen QTLs mapped near Glu‐B1, 20 QTLs mapped near a major plant height QTL on chromosome 4D, and 10 QTLs mapped near a major time to maturity QTL on chromosome 7D. Large QTLs were detected for grain and flour protein content, farinograph absorption, mixograph parameters, and dietary fibre on chromosome 2BS. QTLs for yellow alkaline noodle colour parameter L* mapped to chromosomes 5B and 5D, while the largest QTL for the b* parameter mapped to 7AL.