bluuebunny/crossref_metadata_2025 huggingface dataset:
Can virtual fences be used to control grazing sheep?
Authors: Jouven M. , Leroy H. , Ickowicz A. , Lapeyronie P.
Published: February 2012

Virtual fences (VF) are based on sensory cues delivered to domestic animals with the aim of controlling their spatial behaviour without any physical barrier. VF represent an approach for controlling the distribution of free-ranging large herbivores in large rangeland areas where the implementation of human control or the use of physical fencing is made impossible by their cost, environmental concerns or specific regulations.
The potential of using VF for sheep was investigated by studying the spatial behaviour of groups of 5 or 32 ewes submitted to a commercial animal-borne VF device aimed at containing them in a defined area in a series of experiments. All tests were performed in pasture alleys virtually divided in their centre by a 4-m-wide warning/punishment zone). The ewes were introduced on one side of the zone, the other side being made attractive by the presence of tall grass (feed attractant), the presence of peers (social attractant) or being made unattractive by the presence of short grass (same feed as in the alley). In a first experiment, ewes were trained in groups of 5 with a feed attractant, following a 3-stage procedure: 30-min adaptation, 90-min training with a visual cue (three white strings above the wire of the VF) and 30-min test without a visual cue. In a second experiment, the test stage was repeated for each group with feed, social and zero attractants. In a third experiment, the test with feed attractant was performed with groups of 32 ewes comprising previously trained and equipped ewes mixed in different percentages of trained: naïve (untrained and unequipped) ewes (100 : 0, 75 : 25, 50 : 50 and 0 : 100%). One year later, this test was repeated with a feed attractant either close (30 m) or far (60 m) from the punishment zone. By increasing the distance to the feed attractant, it was anticipated that this would stimulate the conflict of motivation between feed and peers.
Ewes learned readily the concept of VF after a couple of contacts with the punishment zone. In the second experiment in the test with a social attractant, a few trained ewes penetrated the VF to re-associate with peers located in the pen opposite the VF. Expression of the behaviour to challenge or cross the punishment zone differed widely among individuals. In mixed groups, naïve ewes crossed the punishment zone and lead part of their trained peers across the punishment zone, regardless of the distance of the feed attractant from the punishment zone.
The results suggest that VF can be used to alter the distribution of grazing sheep within large fenced areas although they cannot replace conventional fences for absolute control.
Orientation selectivity and noise correlation in awake monkey area V1 are modulated by the gamma cycle
Authors: Womelsdorf Thilo , Lima Bruss , Vinck Martin , Oostenveld Robert , Singer Wolf , Neuenschwander Sergio , Fries Pascal
Published: February 2012

Gamma-band synchronization adjusts the timing of excitatory and inhibitory inputs to a neuron. Neurons in the visual cortex are selective for stimulus orientation because of dynamic interactions between excitatory and inhibitory inputs. We hypothesized that these interactions and hence also orientation selectivity vary during the gamma cycle. We determined for each spike its phase relative to the gamma cycle. As a function of gamma phase, we then determined spike rates and their orientation selectivity. Orientation selectivity was modulated by gamma phase. The firing rate of spiking activity that occurred close to a neuron's mean gamma phase of firing was most orientation selective. This stimulus-selective signal could best be conveyed to postsynaptic neurons if it were not corrupted by noise correlations. Noise correlations between firing rates were modulated by gamma phase such that they were not statistically detectable for the spiking activity occurring close to a neuron's mean gamma phase of firing. Thus, gamma-band synchronization produces spiking activity that carries maximal stimulus selectivity and minimal noise correlation in its firing rate, and at the same time synchronizes this spiking activity for maximal impact on postsynaptic targets.
Cultural adaptation, compounding vulnerabilities and conjunctures in Norse Greenland
Authors: Dugmore Andrew J. , McGovern Thomas H. , Vésteinsson Orri , Arneborg Jette , Streeter Richard , Keller Christian
Published: February 2012

Norse Greenland has been seen as a classic case of maladaptation by an inflexible temperate zone society extending into the arctic and collapse driven by climate change. This paper, however, recognizes the successful arctic adaptation achieved in Norse Greenland and argues that, although climate change had impacts, the end of Norse settlement can only be truly understood as a complex socioenvironmental system that includes local and interregional interactions operating at different geographic and temporal scales and recognizes the cultural limits to adaptation of traditional ecological knowledge. This paper is not focused on a single discovery and its implications, an approach that can encourage monocausal and environmentally deterministic emphasis to explanation, but it is the product of sustained international interdisciplinary investigations in Greenland and the rest of the North Atlantic. It is based on data acquisitions, reinterpretation of established knowledge, and a somewhat different philosophical approach to the question of collapse. We argue that the Norse Greenlanders created a flexible and successful subsistence system that responded effectively to major environmental challenges but probably fell victim to a combination of conjunctures of large-scale historic processes and vulnerabilities created by their successful prior response to climate change. Their failure was an inability to anticipate an unknowable future, an inability to broaden their traditional ecological knowledge base, and a case of being too specialized, too small, and too isolated to be able to capitalize on and compete in the new protoworld system extending into the North Atlantic in the early 15th century.
Reprogramming a module of the 6-deoxyerythronolide B synthase for iterative chain elongation
Authors: Kapur Shiven , Lowry Brian , Yuzawa Satoshi , Kenthirapalan Sanketha , Chen Alice Y. , Cane David E. , Khosla Chaitan
Published: February 2012

Multimodular polyketide synthases (PKSs) have an assembly line architecture in which a set of protein domains, known as a module, participates in one round of polyketide chain elongation and associated chemical modifications, after which the growing chain is translocated to the next PKS module. The ability to rationally reprogram these assembly lines to enable efficient synthesis of new polyketide antibiotics has been a long-standing goal in natural products biosynthesis. We have identified a ratchet mechanism that can explain the observed unidirectional translocation of the growing polyketide chain along the 6-deoxyerythronolide B synthase. As a test of this model, module 3 of the 6-deoxyerythronolide B synthase has been reengineered to catalyze two successive rounds of chain elongation. Our results suggest that high selectivity has been evolutionarily programmed at three types of protein–protein interfaces that are present repetitively along naturally occurring PKS assembly lines.
Trafficking of protein into the recently established photosynthetic organelles of
Paulinella chromatophora
Authors: Nowack Eva C. M. , Grossman Arthur R.
Published: February 2012

Endosymbiotic acquisition of bacteria by a protist, with subsequent evolution of the bacteria into mitochondria and plastids, had a transformative impact on eukaryotic biology. Reconstructing events that created a stable association between endosymbiont and host during the process of organellogenesis—including establishment of regulated protein import into nascent organelles—is difficult because they date back more than 1 billion years. The amoeba
Paulinella chromatophora
contains nascent photosynthetic organelles of more recent evolutionary origin (∼60 Mya) termed chromatophores (CRs). After the initial endosymbiotic event, the CR genome was reduced to approximately 30% of its presumed original size and more than 30 expressed genes were transferred from the CR to the amoebal nuclear genome. Three transferred genes—
psaE
,
psaK1
, and
psaK2
—encode subunits of photosystem I. Here we report biochemical evidence that PsaE, PsaK1, and PsaK2 are synthesized in the amoeba cytoplasm and traffic into CRs, where they assemble with CR-encoded subunits into photosystem I complexes. Additionally, our data suggest that proteins routed to CRs pass through the Golgi apparatus. Whereas genome reduction and transfer of genes from bacterial to host genome have been reported to occur in other obligate bacterial endosymbioses, this report outlines the import of proteins encoded by such transferred genes into the compartment derived from the bacterial endosymbiont. Our study showcases
P
.
chromatophora
as an exceptional model in which to study early events in organellogenesis, and suggests that protein import into bacterial endosymbionts might be a phenomenon much more widespread than currently assumed.
Telomere maintenance and telomerase activity are differentially regulated in asexual and sexual worms
Authors: Tan Thomas C. J. , Rahman Ruman , Jaber-Hijazi Farah , Felix Daniel A. , Chen Chen , Louis Edward J. , Aboobaker Aziz
Published: February 2012

In most sexually reproducing animals, replication and maintenance of telomeres occurs in the germ line and during early development in embryogenesis through the use of telomerase. Somatic cells generally do not maintain telomere sequences, and these cells become senescent in adults as telomeres shorten to a critical length. Some animals reproduce clonally and must therefore require adult somatic mechanisms for maintaining their chromosome ends. Here we study the telomere biology of planarian flatworms with apparently limitless regenerative capacity fueled by a population of highly proliferative adult stem cells. We show that somatic telomere maintenance is different in asexual and sexual animals. Asexual animals maintain telomere length somatically during reproduction by fission or when regeneration is induced by amputation, whereas sexual animals only achieve telomere elongation through sexual reproduction. We demonstrate that this difference is reflected in the expression and alternate splicing of the protein subunit of the telomerase enzyme. Asexual adult planarian stem cells appear to maintain telomere length over evolutionary timescales without passage through a germ-line stage. The adaptations we observe demonstrate indefinite somatic telomerase activity in proliferating stem cells during regeneration or reproduction by fission, and establish planarians as a pertinent model for studying telomere structure, function, and maintenance.
Opposing effects of fructokinase C and A isoforms on fructose-induced metabolic syndrome in mice
Authors: Ishimoto Takuji , Lanaspa Miguel A. , Le MyPhuong T. , Garcia Gabriela E. , Diggle Christine P. , MacLean Paul S. , Jackman Matthew R. , Asipu Aruna , Roncal-Jimenez Carlos A. , Kosugi Tomoki , Rivard Christopher J. , Maruyama Shoichi , Rodriguez-Iturbe Bernardo , Sánchez-Lozada Laura G. , Bonthron David T. , Sautin Yuri Y. , Johnson Richard J.
Published: February 2012

Fructose intake from added sugars correlates with the epidemic rise in obesity, metabolic syndrome, and nonalcoholic fatty liver disease. Fructose intake also causes features of metabolic syndrome in laboratory animals and humans. The first enzyme in fructose metabolism is fructokinase, which exists as two isoforms, A and C. Here we show that fructose-induced metabolic syndrome is prevented in mice lacking both isoforms but is exacerbated in mice lacking fructokinase A. Fructokinase C is expressed primarily in liver, intestine, and kidney and has high affinity for fructose, resulting in rapid metabolism and marked ATP depletion. In contrast, fructokinase A is widely distributed, has low affinity for fructose, and has less dramatic effects on ATP levels. By reducing the amount of fructose for metabolism in the liver, fructokinase A protects against fructokinase C-mediated metabolic syndrome. These studies provide insights into the mechanisms by which fructose causes obesity and metabolic syndrome.
Distribution of fixed beneficial mutations and the rate of adaptation in asexual populations
Authors: Good Benjamin H. , Rouzine Igor M. , Balick Daniel J. , Hallatschek Oskar , Desai Michael M.
Published: February 2012

When large asexual populations adapt, competition between simultaneously segregating mutations slows the rate of adaptation and restricts the set of mutations that eventually fix. This phenomenon of interference arises from competition between mutations of different strengths as well as competition between mutations that arise on different fitness backgrounds. Previous work has explored each of these effects in isolation, but the way they combine to influence the dynamics of adaptation remains largely unknown. Here, we describe a theoretical model to treat both aspects of interference in large populations. We calculate the rate of adaptation and the distribution of fixed mutational effects accumulated by the population. We focus particular attention on the case when the effects of beneficial mutations are exponentially distributed, as well as on a more general class of exponential-like distributions. In both cases, we show that the rate of adaptation and the influence of genetic background on the fixation of new mutants is equivalent to an effective model with a single selection coefficient and rescaled mutation rate, and we explicitly calculate these effective parameters. We find that the effective selection coefficient exactly coincides with the most common fixed mutational effect. This equivalence leads to an intuitive picture of the relative importance of different types of interference effects, which can shift dramatically as a function of the population size, mutation rate, and the underlying distribution of fitness effects.
Adaptive coding of reward prediction errors is gated by striatal coupling
Authors: Park Soyoung Q. , Kahnt Thorsten , Talmi Deborah , Rieskamp Jörg , Dolan Raymond J. , Heekeren Hauke R.
Published: February 2012

To efficiently represent all of the possible rewards in the world, dopaminergic midbrain neurons dynamically adapt their coding range to the momentarily available rewards. Specifically, these neurons increase their activity for an outcome that is better than expected and decrease it for an outcome worse than expected, independent of the absolute reward magnitude. Although this adaptive coding is well documented, it remains unknown how this rescaling is implemented. To investigate the adaptive coding of prediction errors and its underlying rescaling process, we used human functional magnetic resonance imaging (fMRI) in combination with a reward prediction task that involved different reward magnitudes. We demonstrate that reward prediction errors in the human striatum are expressed according to an adaptive coding scheme. Strikingly, we show that adaptive coding is gated by changes in effective connectivity between the striatum and other reward-sensitive regions, namely the midbrain and the medial prefrontal cortex. Our results provide evidence that striatal prediction errors are normalized by a magnitude-dependent alteration in the interregional connectivity within the brain's reward system.
Fracture of crystalline silicon nanopillars during electrochemical lithium insertion
Authors: Lee Seok Woo , McDowell Matthew T. , Berla Lucas A. , Nix William D. , Cui Yi
Published: February 2012

From surface hardening of steels to doping of semiconductors, atom insertion in solids plays an important role in modifying chemical, physical, and electronic properties of materials for a variety of applications. High densities of atomic insertion in a solid can result in dramatic structural transformations and associated changes in mechanical behavior: This is particularly evident during electrochemical cycling of novel battery electrodes, such as alloying anodes, conversion oxides, and sulfur and oxygen cathodes. Silicon, which undergoes 400% volume expansion when alloying with lithium, is an extreme case and represents an excellent model system for study. Here, we show that fracture locations are highly anisotropic for lithiation of crystalline Si nanopillars and that fracture is strongly correlated with previously discovered anisotropic expansion. Contrary to earlier theoretical models based on diffusion-induced stresses where fracture is predicted to occur in the core of the pillars during lithiation, the observed cracks are present only in the amorphous lithiated shell. We also show that the critical fracture size is between about 240 and 360 nm and that it depends on the electrochemical reaction rate.
Enslaved African Women in Nineteenth-Century Iran: The Life of Fezzeh Khanom of Shiraz
Authors: Lee Anthony A.
Published: February 2012

Fezzeh Khanom (c. 1835–82), an African woman, was a slave of Sayyed ‘Ali-Mohammad of Shiraz, the Bab. Information about her life can be recovered from various pious Baha'i histories. She was honored, and even venerated by Babis, though she remained subordinate and invisible. The paper makes the encouraging discovery that a history of African slavery in Iran is possible, even at the level of individual biographies. Scholars estimate that between one and two million slaves were exported from Africa to the Indian Ocean trade in the nineteenth century, most to Iranian ports. Some two-thirds of African slaves brought to Iran were women intended as household servants and concubines. An examination of Fezzeh Khanom's life can begin to fill the gaps in our knowledge of enslaved women in Iran. The paper discusses African influences on Iranian culture, especially in wealthy households and in the royal court. The limited value of Western legal distinctions between slavery and freedom when applied to the Muslim world is noted.
aPKC phosphorylates JAM-A at Ser285 to promote cell contact maturation and tight junction formation
Authors: Iden Sandra , Misselwitz Steve , Peddibhotla Swetha S.D. , Tuncay Hüseyin , Rehder Daniela , Gerke Volker , Robenek Horst , Suzuki Atsushi , Ebnet Klaus
Published: February 2012

The PAR-3–atypical protein kinase C (aPKC)–PAR-6 complex has been implicated in the development of apicobasal polarity and the formation of tight junctions (TJs) in vertebrate epithelial cells. It is recruited by junctional adhesion molecule A (JAM-A) to primordial junctions where aPKC is activated by Rho family small guanosine triphosphatases. In this paper, we show that aPKC can interact directly with JAM-A in a PAR-3–independent manner. Upon recruitment to primordial junctions, aPKC phosphorylates JAM-A at S285 to promote the maturation of immature cell–cell contacts. In fully polarized cells, S285-phosphorylated JAM-A is localized exclusively at the TJs, and S285 phosphorylation of JAM-A is required for the development of a functional epithelial barrier. Protein phosphatase 2A dephosphorylates JAM-A at S285, suggesting that it antagonizes the activity of aPKC. Expression of nonphosphorylatable JAM-A/S285A interferes with single lumen specification during cyst development in three-dimensional culture. Our data suggest that aPKC phosphorylates JAM-A at S285 to regulate cell–cell contact maturation, TJ formation, and single lumen specification.
Aurora B controls kinetochore–microtubule attachments by inhibiting Ska complex–KMN network interaction
Authors: Chan Ying Wai , Jeyaprakash A. Arockia , Nigg Erich A. , Santamaria Anna
Published: February 2012

The KMN network (named according to the acronym for KNL1, Mis12, and Ndc80) and the more recently identified Ska complex (Ska1–3) have been shown to mediate kinetochore (KT)–microtubule (MT) attachments. How these two complexes cooperate to achieve stable end-on attachments remains unknown. In this paper, we show that Aurora B negatively regulates the localization of the Ska complex to KTs and that recruitment of the Ska complex to KTs depends on the KMN network. We identified interactions between members of the KMN and Ska complexes and demonstrated that these interactions are regulated by Aurora B. Aurora B directly phosphorylated Ska1 and Ska3 in vitro, and expression of phosphomimetic mutants of Ska1 and Ska3 impaired Ska KT recruitment and formation of stable KT–MT fibers (K-fibers), disrupting mitotic progression. We propose that Aurora B phosphorylation antagonizes the interaction between the Ska complex and the KMN network, thereby controlling Ska recruitment to KTs and stabilization of KT–MT attachments.
Indirect inhibition of 26S proteasome activity in a cellular model of Huntington’s disease
Authors: Hipp Mark S. , Patel Chetan N. , Bersuker Kirill , Riley Brigit E. , Kaiser Stephen E. , Shaler Thomas A. , Brandeis Michael , Kopito Ron R.
Published: February 2012

Pathognomonic accumulation of ubiquitin (Ub) conjugates in human neurodegenerative diseases, such as Huntington’s disease, suggests that highly aggregated proteins interfere with 26S proteasome activity. In this paper, we examine possible mechanisms by which an N-terminal fragment of mutant huntingtin (htt; N-htt) inhibits 26S function. We show that ubiquitinated N-htt—whether aggregated or not—did not choke or clog the proteasome. Both Ub-dependent and Ub-independent proteasome reporters accumulated when the concentration of mutant N-htt exceeded a solubility threshold, indicating that stabilization of 26S substrates is not linked to impaired Ub conjugation. Above this solubility threshold, mutant N-htt was rapidly recruited to cytoplasmic inclusions that were initially devoid of Ub. Although synthetically polyubiquitinated N-htt competed with other Ub conjugates for access to the proteasome, the vast majority of mutant N-htt in cells was not Ub conjugated. Our data confirm that proteasomes are not directly impaired by aggregated N-terminal fragments of htt; instead, our data suggest that Ub accumulation is linked to impaired function of the cellular proteostasis network.
A germinal center–independent pathway generates unswitched memory B cells early in the primary response
Authors: Taylor Justin J. , Pape Kathryn A. , Jenkins Marc K.
Published: February 2012

Memory B cells can be produced from the classical germinal center (GC) pathway or a less understood GC-independent route. We used antigen-based cell enrichment to assess the relative contributions of these pathways to the polyclonal memory B cell pool. We identified a CD38+ GL7+ B cell precursor population that differentiated directly into IgM+ or isotype-switched (sw) Ig+ memory B cells in a GC-independent fashion in response to strong CD40 stimulation. Alternatively, CD38+ GL7+ B cell precursors had the potential to become Bcl-6+ GC cells that then generated primarily swIg+ memory B cells. These results demonstrate that early IgM+ and swIg+ memory B cells are products of a GC-independent pathway, whereas later switched Ig+ memory B cells are products of GC cells.
Weight monitoring in patients with severe heart failure (WISH). A randomized controlled trial
Authors: Lyngå Patrik , Persson Hans , Hägg‐Martinell Ann , Hägglund Ewa , Hagerman Inger , Langius‐Eklöf Ann , Rosenqvist Mårten
Published: February 2012

Aims

This multicentre, randomized controlled trial hypothesized that daily electronic transmission of body weight to a heart failure (HF) clinic will reduce cardiac hospitalization in patients recently hospitalized with HF.

Methods and results

A total of 344 patients were randomized to either an intervention group (IG) or a control group (CG). Of the 319 patients included in the final analysis, the mean age was 73 years (SD 10.2), 75% were males, and 57% had a left ventricular ejection fraction (LVEF) <30%. Patients in both groups were recommended to weigh themselves daily and, in the case of sudden weight gain >2 kg in 3 days, to contact the HF clinic. Patients in the IG were given an electronic scale and the weight was automatically transmitted to and monitored at the HF clinic. No significant differences were found for the primary endpoint, cardiac re‐hospitalization [70/153 CG, 70/166 IG; hazard ratio (HR) 0.90, 95% confidence interval (CI) 0.65–1.26, P = 0.54], or for the secondary endpoints, which included all‐cause hospitalization (84/153 CG, 79/166 IG; HR 0.83, 95% CI 0.61–1.13, P = 0.24), death from any cause (8/153 CG, 5/166 IG; HR 0.57, 95% CI 0.19–1.73, P = 0.32), or the composite endpoint of cardiac hospitalization and death from any cause (78/153 CG, 75/166 IG; HR 0.90, 95% CI 0.65–1.26, P = 0.54). Subgroup analyses did not show any benefits for patients in the IG despite their more frequent monitoring; 398 occasions compared with 30 occasions in the CG.

Conclusion

Daily electronic transmission of body weight and monitoring three times a week did not decrease hospitalization or death in HF patients followed up at a HF clinic.
Subclassification and Biochemical Analysis of Plant Papain-Like Cysteine Proteases Displays Subfamily-Specific Characteristics
Authors: Richau Kerstin H. , Kaschani Farnusch , Verdoes Martijn , Pansuriya Twinkal C. , Niessen Sherry , Stüber Kurt , Colby Tom , Overkleeft Hermen S. , Bogyo Matthew , Van der Hoorn Renier A.L.
Published: February 2012

Papain-like cysteine proteases (PLCPs) are a large class of proteolytic enzymes associated with development, immunity, and senescence. Although many properties have been described for individual proteases, the distribution of these characteristics has not been studied collectively. Here, we analyzed 723 plant PLCPs and classify them into nine subfamilies that are present throughout the plant kingdom. Analysis of these subfamilies revealed previously unreported distinct subfamily-specific functional and structural characteristics. For example, the NPIR and KDEL localization signals are distinctive for subfamilies, and the carboxyl-terminal granulin domain occurs in two PLCP subfamilies, in which some individual members probably evolved by deletion of the granulin domains. We also discovered a conserved double cysteine in the catalytic site of SAG12-like proteases and two subfamily-specific disulfides in RD19A-like proteases. Protease activity profiling of representatives of the PLCP subfamilies using novel fluorescent probes revealed striking polymorphic labeling profiles and remarkably distinct pH dependency. Competition assays with peptide-epoxide scanning libraries revealed common and unique inhibitory fingerprints. Finally, we expand the detection of PLCPs by identifying common and organ-specific protease activities and identify previously undetected proteases upon labeling with cell-penetrating probes in vivo. This study provides the plant protease research community with tools for further functional annotation of plant PLCPs.
Basics of skin structure and function in elasmobranchs: a review
Authors: Meyer W. , Seegers U.
Published: February 2012

In contrast to the bony fishes, particularly the teleosts, the integument of elasmobranchs is rather unknown. Therefore, a description of the basic structural and functional features of shark and ray skin is given, based on a review of the literature and published or unpublished findings of the authors. The latter aspect makes it possible to document in more detail the specific structure of the skin layers regarding, particularly, the epidermis and its cell spectrum, the more or less robust dermis with its specific features, the very special scales with their derivates and the sophisticated sensoric integumental equipment. As far as possible, all important structures are discussed including their typical biological functions and results from applied scientific work. To some extent the information given is evaluated as compared with the much broader knowledge from the Osteichthyes.
A global review of species‐specific shark‐fin‐to‐body‐mass ratios and relevant legislation
Authors: Biery L. , Pauly D.
Published: February 2012

In this review, shark‐fin‐to‐body‐mass ratios, which have been legislated by several countries as a means of regulating and monitoring shark fisheries, have been compiled and reviewed. Observed and legislated wet‐fin‐mass‐to‐round‐mass (Mfw:Mr) ratios have been collected for 50 species and eight countries. Wet to dry‐fin mass conversion factors have also been reviewed. Existing shark fishery legislation was compiled by political entity and regional fishery management organizations (RFMO). The mean observed Mfw:Mr ratio for all species was 3·0%, but actual fin to body‐mass ratios varied considerably by species and location. Species‐specific mean ratios ranged from 1·1 to 10·9%, and estimated mean ratios ranged from 1·5 to 6·1% by country, depending on fin‐cutting practices and the mix of exploited species. The mean conversion factor for wet to dry‐fin mass was 0·43. Shark‐related legislation was found to exist in 37 countries and the 22 maritime members of the European Union, and shark‐related regulations have been designated by nine RFMOs. Results suggest that currently regulated ratios may not be appropriate for all species and fin‐cutting practices, and regulations based on generalized ratios for all sharks may be inadequate. Alternative policies may be necessary for the effective management of global shark fisheries.
Effects of body mass and temperature on routine metabolic rate of juvenile largemouth bronze gudgeon Coreius guichenoti
Authors: Luo Y. P. , Wang Q. Q.
Published: February 2012

The effects of body mass (M) and temperature (T) on routine metabolic rate (mR) were assessed in the largemouth bronze gudgeon Coreius guichenoti, from Three Gorges Reservoir, Yangtze River, China. The mR increased with increasing M by factors (b‐value in the equation mR = aMb) of 0·843, 0·800, 0·767, 0·788 and 0·822 at 10, 15, 20, 25 and 30° C, respectively. A significant interaction between M and T on mR was observed. The variation in the b‐value at different T suggests that the b‐values were not consistent with the universal allometric exponent 0·75. After controlling for M, the relationship between the normalized standard metabolic rate (mS, mg O2 kg−1 h−1) and T was described by an exponential equation: mS = 9·89e(0·093T). The results indicate that the effects of M on mR depend on T. The increased water temperature induced by dam construction on the Yangtze River may cause a marked increase in energy demand by this species, with potential ecological consequences.
Blue shark Prionace glauca fin‐to‐carcass‐mass ratios in Spain and implications for finning ban enforcement
Authors: Santana‐Garcon J. , Fordham S. , Fowler S.
Published: February 2012

This study examines the processing of fins from blue sharks Prionace glauca caught by the Spanish longline fleet and landed in Vigo, Spain, and implications of these practices for enforcing the E.U. ban on shark finning, which relies on a maximum fin‐to‐carcass‐mass ratio. Two major sources of variability in fin‐to‐carcass ratios are quantified and discussed: (1) the fin set (type and number of fins retained from each shark) and (2) the cutting method used to separate fins from carcasses. The significant differences in fin‐to‐carcass‐mass ratios between fin sets or cutting procedure demonstrates that the ratio limit is problematic and, conclusively, in order to facilitate proper enforcement, fishermen should be required to land all sharks with the fins still naturally attached to the bodies.
Predictors of the 2‐year recurrence and persistence of alcohol dependence
Authors: Boschloo Lynn , Vogelzangs Nicole , van den Brink Wim , Smit Johannes H. , Beekman Aartjan T. F. , Penninx Brenda W. J. H.
Published: February 2012

Aims  To identify independent risk factors of the recurrence of alcohol dependence (AD) in people with a remitted disorder at baseline and persistence of AD in people with a current disorder at baseline.

Design  Prospective cohort study with assessments at baseline and 2‐year follow‐up.

Setting  Recruitment from the general population, primary care and out‐patient mental health‐care services.

Participants  People with remitted AD (n = 253) and current AD (n = 135).

Measurements  Recurrence and persistence of AD during 2‐year follow‐up were established using the Composite International Diagnostic Interview (CIDI) interview based on DSM‐IV. Logistic regression analyses were performed to explore the role of potential risk factors (i.e. baseline severity of alcohol problems, measures for depression and anxiety, socio‐demographics, vulnerability factors and addiction‐related factors) as independent predictors of a negative course.

Findings  Overall recurrence and persistence rates of AD were 14.6 and 40.7%, respectively, and were highly conditional on the severity of alcohol problems [adjusted odds ratio (OR) per standard deviation (SD) increase: OR = 3.64, 95% confidence interval (CI): 2.21–6.01 and OR = 2.12, 95% CI: 1.32–3.40, respectively). Severity of depressive/anxiety symptoms was an additional independent predictor of the recurrence of AD, whereas male gender and high education were significant independent risk factors of the persistence of AD.

Conclusions   Alcohol dependence has a dynamic course, with only moderate levels of diagnostic stability. Both recurrence and persistence of alcohol dependence are highly dependent on severity of baseline alcohol problems, whereas severity of depressive/anxiety symptoms predicts only the recurrence of alcohol dependence. Both measures may be useful in identifying people at an increased risk of a negative course and who could be targeted by prevention strategies.
Youth with disabilities' perspectives of the environment and participation: a qualitative meta‐synthesis
Authors: Kramer J. M. , Olsen S. , Mermelstein M. , Balcells A. , Liljenquist K.
Published: February 2012

Meta‐syntheses can enhance our knowledge regarding the impact of the environment on the participation of youth with disabilities and generate theoretical frameworks to inform policy and best practices. The purpose of this study was to describe school‐aged youth with disabilities' perspectives regarding the impact of the environment and modifications on their participation. A meta‐synthesis systematically integrates qualitative evidence from multiple studies. Six databases were searched and 1287 citations reviewed for inclusion by two independent raters; 15 qualitative articles were selected for inclusion. Two independent reviewers evaluated the quality of each study and coded the results section. Patterns between codes within and across articles were examined using a constant comparative approach. Environments may be more or less inclusive for youth with disabilities depending upon others' understanding of individual abilities and needs, youth involvement in decisions about accommodations, and quality of services and policies. Youth implemented strategies to negotiate environmental barriers and appraised the quality of their participation based on the extent to which they engaged alongside peers. This meta‐synthesis generated a framework illustrating the relationship between the environment, modifications and participation, and provided a conceptualization of participation grounded in the lived experiences of youth with disabilities. Findings reveal gaps in current knowledge and highlight the importance of involving youth with disabilities in decision making.
Effects of oestrogen and testosterone therapy on serum metabolites in postmenopausal women
Authors: Zang Hong , Moritz Thomas , Norstedt Gunnar , Hirschberg Angelica L. , Tollet‐Egnell Petra
Published: February 2012

Objectives

Metabolite profiles of body fluids or tissue extracts can be regarded as important indicators of physiological or pathological states. Whether hormone‐specific alterations of the serum metabolome can be identified using this technique has not been tested yet. The aim of this study was to investigate metabolic responses during hormone therapy in postmenopausal women by a nontargeted metabolomics approach.

Methods

Sixty naturally postmenopausal women were randomly assigned to treatment with testosterone undecanoate 40 mg every second day; estradiol valerate 2 mg daily; or the combination of both. Serum metabolites were determined by gas chromatography‐mass spectrometry (GC‐MS) before and after 3 months of treatment. Metabolites affected by the treatment were identified and correlated with changes in insulin sensitivity and lipid profiles.

Results

Treatment‐dependent and hormone‐specific effects on serum metabolites were observed, ranging between 69% reduction and 184% increase, but the metabolites that best explained the differences could not be structurally identified. Effects on annotated metabolites were less associated with clinical parameters as compared to established serum markers for adverse lipid and carbohydrate metabolism, such as cholesterol and triglycerides. However, cystine, lysine and tyrosine were shown to change in correlation with insulin sensitivity and high‐density lipoprotein cholesterol levels in response to testosterone, indicating that those responses were somehow related to each other.

Conclusions

Oestrogen‐ and androgen‐specific alterations in the serum metabolome could be identified using GC‐MS, reflecting hormone‐specific effects on whole body metabolism. New knowledge regarding steroid‐mediated metabolic responses within different tissues might be obtained using a similar approach on tissue extracts.
Regenerative pulmonary medicine: potential and promise, pitfalls and challenges
Authors: Anversa Piero , Perrella Mark A. , Kourembanas Stella , Choi Augustine M. K. , Loscalzo Joseph
Published: February 2012

Eur J Clin Invest 2012

Background  Chronic lung diseases contribute significantly to the morbidity and mortality of the population. There are few effective treatments for many chronic lung diseases, and even fewer therapies that can arrest or reverse the progress of the disease.

Design  In this review, we present the current state of regenerative therapies for the treatment of chronic lung diseases. We focus on endothelial progenitor cells, mesenchymal stem cells, and endogenous lung stem/progenitor cells; summarize the work to date in models of lung diseases for each of these therapies; and consider their potential benefits and risks as viable therapies for patients with lung diseases.

Conclusions  Cell‐based regenerative therapies for lung diseases offer great promise, with preclinical studies suggesting that the next decade should provide the evidence necessary for their ultimate application to our therapeutic armamentarium.
Omnivory, vertical food‐web structure and system productivity: stable isotope analysis of freshwater planktonic food webs
Authors: FRANCE ROBERT L.
Published: February 2012

1. The energetic hypothesis proposes that the vertical structure of food webs should increase in height with increasing system productivity. I measured the trophic positions and extent of trophic separation between the invertebrate planktivores Mysis relicta and Chaoborus spp. and their putative zooplankton prey along a gradient of lake productivity with the use of stable nitrogen isotopes.

2. In lakes of low productivity, these planktivores were found to be herbivorous, becoming omnivorous at intermediate lake productivities, and only able to be truly zooplanktivorous as lakes approached mesotrophy. A subsequent secondary analysis of literature data revealed that the strength of top‐down trophic cascades among these organisms increased with lake productivity as reflected by relationships between the abundance of planktivores and that of phytoplankton.

3. Increased omnivory under conditions of low productivity, effectively shortening the vertical structure of food webs as predicted by the energetic hypothesis, may produce increased community stability.
The effects of nutrient enrichment on a freshwater meiofaunal assemblage
Authors: RISTAU KAI , FAUPEL MICHAEL , TRAUNSPURGER WALTER
Published: February 2012

1. The effects of eutrophication on phytoplankton, zooplankton and fish in lakes are well known. By contrast, little is known about the response of the zoobenthos to nutrient enrichment, while smaller organisms, such as the meiofauna, have for the most part been neglected.

2. In a long‐term (16 months) microcosm experiment, we assessed the effects of five levels of nutrients [total phosphorus (TP), 7–250 μg L−1; nitrate, 2–8 mg L−1] on a freshwater meiofaunal assemblage and on nematode diversity in particular.

3. Within the first 8 months, meiofaunal succession was only weakly affected, whereas, during the last 4 months, nutrient addition influenced most of the main taxa, with a concomitant change in the assemblage structure.

4. The density of the numerically dominant nematodes decreased upon nutrient enrichment, whereas ostracods became more numerous. Other taxa, including copepods, reached a maximum at intermediate nutrient levels or, in case of oligochaetes, were almost unaffected by nutrient enrichment. However, the changes in the density of the main taxa were usually insufficient to alter their biomass. Consequently, meiofaunal biomass was remarkably unresponsive to nutrient addition, while meiofaunal density displayed a unimodal relationship, with a peak at a TP concentration of 30 μg L−1. In addition, nematode species richness decreased significantly with increasing nutrient concentrations.

5. We hypothesise that the response of meiofaunal taxa to nutrients is attributable to the development of primary producers, which shifted with enrichment from low densities of edible diatoms and unicellular green algae to large standing stocks of inedible forms, such as Lemna minor and Cladophora spp.
Periprostatic lymph node metastasis in prostate cancer and its clinical significance
Authors: Deng Fang‐Ming , Mendrinos Savvas E , Das Kasturi , Melamed Jonathan
Published: February 2012

Deng F‐M, Mendrinos S E, Das K & Melamed J  (2012) Histopathology 60, 1004–1008 Periprostatic lymph node metastasis in prostate cancer and its clinical significance

Aims:  To evaluate the potential of periprostatic lymph node (LN) as a staging indicator, particularly with the use of methods for enhanced detection of micrometastasis.

Methods and results:  We retrieved cases with periprostatic LN from radical prostatectomy specimens accrued between 1997 and 2007 at our institution. Twenty‐one (0.8%) of 2663 radical prostatectomy specimens had periprostatic LNs (total number of LNs = 22). LN size ranged from 0.8 to 4.7 mm. Most of the periprostatic LNs were located close to the posterior base. Seven (32%) of 22 LNs were involved by metastatic prostate cancer (PCa), including five detected on routine haematoxylin and ceosin slides and an additional two detected only by immunohistochemistry. Cases with periprostatic LNs had a significantly higher metastatic rate (29%; six of 21) compared to those with pelvic LNs sampled at radical prostectatomy in our institution (1.9%). When compared to cases with negative periprostatic LNs (n = 15), the tumour characteristics of cases with metastatic periprostatic LNs (n = 6) included higher tumour volume, Gleason score, stage and a greater propensity for prostate‐specific antigen (PSA) recurrence.

Conclusions:  Despite their infrequent identification, periprostatic LNs if detected in the radical prostatectomy specimen should be evaluated with greater scrutiny (step sections and/or immunohistochemical studies) to evaluate their prognostic potential.
Hepatocellular adenoma in glycogen storage disorder type I: a clinicopathological and molecular study
Authors: Sakellariou Stratigoula , Al‐Hussaini Hussa , Scalori Astrid , Samyn Marianne , Heaton Nigel , Portmann Bernard , Tobal Khalid , Quaglia Alberto
Published: February 2012

Sakellariou S, Al‐Hussaini H, Scalori A, Samyn M, Heaton N, Portmann B, Tobal K & Quaglia A

(2012) Histopathology 60, E58–E65

Hepatocellular adenoma in glycogen storage disorder type I: a clinicopathological and molecular study

Aims:  Glycogen storage disease type I is a metabolic disorder resulting from deficiency of the glucose‐6‐phosphate complex. Long‐term complications include the development of hepatocellular adenoma (HCA). In this retrospective study, our aim was to reclassify according to geno‐phenotypic characteristics nodular lesions identified in hepatectomy specimens of such patients transplanted between 1998 and 2008 at our institution.

Methods and results:  Clinicopathological data of seven consecutive transplanted patients with glycogen storage disease type I were reviewed. Liver nodules were re‐examined histologically and by immunohistochemistry. Molecular analysis was performed additionally in a case with specific features. Four patients had multiple tumours. We concluded that 26 of 38 nodules available for study had features of inflammatory hepatocellular adenomas, seven comprised adenomas not otherwise specified and five were found to be focal nodular hyperplasia.

Conclusions:  Further studies are needed to clarify the pathogenesis of hepatocellular adenomas in glycogen storage disease; in particular to determine whether they share abnormal metabolic pathways with inflammatory adenomas in the general population. Testing for acute phase proteins may be a helpful tool in the early detection of HCA in such patients. Finally, there is a need to further define their risk of malignant transformation, in relation to age and possible cofactors.
Elevated expression of astrocyte elevated gene‐1 (AEG‐1) is correlated with cisplatin‐based chemoresistance and shortened outcome in patients with stages III–IV serous ovarian carcinoma
Authors: Li Cong , Li Yinghong , Wang Xiaochuan , Wang Zhenyu , Cai Jianping , Wang Lihua , Zhao Yulan , Song Hongtao , Meng Xiangning , Ning Xiaoming , Xu Chunlin , Lin Mei , Li Lejing , Geng Jingshu
Published: February 2012

Li C, Li Y, Wang X, Wang Z, Cai J, Wang L, Zhao Y, Song H, Meng X, Ning X, Xu C, Lin M, Li L & Geng J  (2012) Histopathology 60, 953–963

Elevated expression of astrocyte elevated gene‐1 (AEG‐1) is correlated with cisplatin‐based chemoresistance and shortened outcome in patients with stages III–IV serous ovarian carcinoma

Aims:  To correlate astrocyte elevated gene‐1 (AEG‐1) expression with the clinicopathological features and outcome of patients with stages III–IV ovarian serous carcinoma, and to clinically assess the involvement of AEG‐1 in acquired cisplatin resistance.

Methods and results:  The frequency and intensity of immunohistochemical AEG‐1 expression increased in a step‐wise fashion from normal to chemosensitive to chemoresistant tissues. These observations were confirmed by Western blot analysis. AEG‐1 expression level was correlated with lymph nodal metastasis, histological differentiation, residual tumour size and response to primary chemotherapy. Five‐year progression‐free survival (PFS) and overall survival (OS) rates were lower in the high‐expression group than that in the low‐expression group. AEG‐1 overexpression was an independent but poor prognostic factor in the OS and PFS of these patients, as determined by multivariate Cox regression analysis. Multivariate logistic regression analysis revealed that the presence of cisplatin‐based chemoresistance was significantly associated with expression level of AEG‐1 and the degree of residual disease (P = 0.0001 and P = 0.0027, respectively).

Conclusion:  Our findings indicate that tumour AEG‐1 overexpression is associated with poor prognosis and cisplatin resistance in advanced serous ovarian cancer.
The future of testis research is turning 6! Six years of International Network for Young Researchers in Male Fertility
Authors: Tüttelmann F. , De Gendt K. , Amaral A. , Giachini C C. , Welsh M. , Blomberg Jensen M. , Nurmio M. , Wahlgren A. , Stukenborg J. B.
Published: February 2012

The ‘International Network for Young Researchers in Male Fertility’ has now turned 6 years old and offers a platform that stimulates scientific exchange as well as the development of international cooperation for young researchers. We report on our scope and the exciting achievements, amongst others, the continually increasing number of participants and the growing success of our annual meetings.