bluuebunny/crossref_metadata_2025 huggingface dataset:
225 ADDITION OF EQUINE CHORIONIC GONADOTROPIN TO A TRADITIONAL FOLLICLE STIMULATING HORMONE PROTOCOL FOR SUPEROVULATION OF BOS TAURUS BEEF COWS
Authors: Davis R. L. , Arteaga A. , Hasler J. F.
Published: December 2011

This study examined the superovulatory responses of Bos taurus beef cows maintained in a commercial embryo transfer facility. Donors were superovulated 1 to 3 times each with either a traditional 8 injection FSH protocol (controls, n = 126) or 6 injections of FSH with the seventh or eighth FSH treatments replaced by 2 injections of eCG (treatment, n = 134). During the 5-month study, 132 donors were alternatively assigned to a control or treatment group for a single superovulation and an additional 62 animals were superovulated 2 (n = 58) or 3 times (n = 4) in a crossover design. Although 14 beef breeds were represented in the study, 87% of the cows were Angus, Red Angus, Polled Hereford, or Charolais. All donors were synchronized on Day 0 with a CIDR, 5 mg of oestradiol-17β and 100 mg of progesterone. Starting on Day 4 (p.m.), controls were injected twice daily for 4 days with descending doses of porcine FSH (Folltropin-V®, Bioniche Animal Health, Belleville, Ontario, Canada). Cows received 750 μg of cloprostenol (Estrumate®, Intervet Schering-Plough, Summit, NJ, USA) at the seventh FSH injection and the CIDR was removed at the eighth FSH injection. Based on previous experience with specific, individual animals, total FSH dose per donor ranged from 240 to 400 mg. However, 74% of treatments involved 380 mg for controls and 310 mg for treated donors that received eCG. In addition, donors that were superovulated more than once received the same FSH dose in the crossover, treatment-control design. In the treatment group, 200 IU of eCG (Pregnecol™ 6000, Bioniche Animal Health) was substituted for the seventh and eighth FSH injections. Inseminations were conducted on a timed AI basis, with one unit of semen 32 h and a second 48 h following CIDR removal. Results were analysed by ANOVA as shown in Table 1. Although more ova/embryos and unfertilized ova (UFO) were recovered in the control group, the control and treatment groups did not differ in the number of grade 1, 2, or 3 embryos or in the number of degenerate embryos. Previous superovulation studies in South America using eCG to replace the last 2 injections of FSH resulted in more total ova/embryos in Nelore cows but not heifers and in more embryos in Brangus and Sindhi cows. The mean embryo production for the control cows in this study was high and the addition of eCG in the protocol did not improve embryo production. Failure of eCG to increase the number of embryos for Bos taurus cows in this study compared with previous studies may be due to differences with Bos taurus versus Bos indicus breeds or differences in management factors between Canada and South America. The high response rate in the controls may also have contributed to the failure of any advantage of adding eCG to the treatment protocol.

Table 1.Mean numbers (± SEM) of ova and embryos recovered from Bos taurus females superovulated with 2 different protocols
51 CHANGING ROOSTER SPERM MEMBRANES TO FACILITATE CRYOPRESERVATION
Authors: Tarvis K. M. , Purdy P. H. , Graham J. K.
Published: December 2011

Cryopreservation damages rooster sperm membranes. Part of this damage is due to membrane transitioning from the fluid to the gel state as temperature is reduced. Some of this damage may be prevented by increasing membrane fluidity at low temperatures by incorporating cholesterol or unsaturated lipids into the membrane. Different concentrations of cholesterol-loaded cyclodextrins (CLC) and lipid-loaded cyclodextrins (LLC) containing 1,2-dilinoleoyl-sn-glycero-3-phosphocholine; 1,2-dilinoleoyl-rac-glycerol; and 1,2-dilinolenoyl-sn-glycero-3-phosphocholine were added to rooster sperm to determine if they improved cryopreservation. Osmotic stresses when cryoprotectants (CPA) are added to the cells before freezing and when the CPA are removed from cells after thawing also cause membrane damage. To minimize this damage, low molecular weight CPA with high membrane permeability were tested to determine their effectiveness for cryopreserving sperm. Rooster semen was collected from several birds, pooled and diluted to 800 million sperm mL–1 at 5°C in Lake's Low Temperature diluent (LLT). Sperm were treated with either LLC (0.25, 0.5, 1, 1.5, 2, 4 and 6 mg mL–1) or CLC (0.5, 1 and 2 mg mL–1) for 30 min. The sperm were diluted 1:1 with LLT containing 18% CPA, resulting in final CPA concentrations of 9%. The CPA tested were glycerol (G), methylacetamide (MA), dimethylformamide (DMF), methylformamide (MF) and ethylene glycol (EG). The sperm were frozen in liquid nitrogen vapor and stored in liquid nitrogen. Straws were thawed in 5°C water and sperm motility and membrane integrity analysed immediately. Sperm motility was measured using computer-assisted sperm analysis (CASA) and membrane integrity was analysed by flow cytometry using propidium iodide to detect cells with damaged membranes. Data were analysed by ANOVA and means separated using Student–Newman–Keuls multiple comparison test. Addition of LLC and CLC did improve sperm cryosurvival rates (P > 0.05). Using G as the CPA resulted in higher percentages of motile (54%) and viable (58%) sperm than MA (47 and 52%; P < 0.05), whereas DMF, EG and MF resulted in less than 45% motile cells (P < 0.05). In conclusion, altering sperm membrane composition using CLC and LLC did not improve post-thaw motility or viability in rooster sperm. Although MA did not protect the rooster sperm from cryodamage as effectively as G, future assays will need to determine the fertilizing capacity of sperm frozen using these CPA.
We thank CSU-CVBMS for funding support.
Plastid terminal oxidase 2 (PTOX2) is the major oxidase involved in chlororespiration in
Chlamydomonas
Authors: Houille-Vernes Laura , Rappaport Fabrice , Wollman Francis-André , Alric Jean , Johnson Xenie
Published: December 2011

By homology with the unique plastid terminal oxidase (PTOX) found in plants, two genes encoding oxidases have been found in the
Chlamydomonas
genome,
PTOX1
and
PTOX2
. Here we report the identification of a knockout mutant of
PTOX2
. Its molecular and functional characterization demonstrates that it encodes the oxidase most predominantly involved in chlororespiration in this algal species. In this mutant, the plastoquinone pool is constitutively reduced under dark-aerobic conditions, resulting in the mobile light-harvesting complexes being mainly, but reversibly, associated with photosystem I. Accordingly, the
ptox2
mutant shows lower fitness than wild type when grown under phototrophic conditions. Single and double mutants devoid of the cytochrome
b
6
f
complex and PTOX2 were used to measure the oxidation rates of plastoquinols via PTOX1 and PTOX2. Those lacking both the cytochrome
b
6
f
complex and PTOX2 were more sensitive to light than the single mutants lacking either the cytochrome
b
6
f
complex or PTOX2, which discloses the role of PTOX2 under extreme conditions where the plastoquinone pool is overreduced. A model for chlororespiration is proposed to relate the electron flow rate through these alternative pathways and the redox state of plastoquinones in the dark. This model suggests that, in green algae and plants, the redox poise results from the balanced accumulation of PTOX and NADPH dehydrogenase.
Myopathy caused by mammalian target of rapamycin complex 1 (mTORC1) inactivation is not reversed by restoring mitochondrial function
Authors: Romanino Klaas , Mazelin Laetitia , Albert Verena , Conjard-Duplany Agnès , Lin Shuo , Bentzinger C. Florian , Handschin Christoph , Puigserver Pere , Zorzato Francesco , Schaeffer Laurent , Gangloff Yann-Gaël , Rüegg Markus A.
Published: December 2011

Mammalian target of rapamycin complex 1 (mTORC1) is central to the control of cell, organ, and body size. Skeletal muscle-specific inactivation of mTORC1 in mice results in smaller muscle fibers, fewer mitochondria, increased glycogen stores, and a progressive myopathy that causes premature death. In mTORC1-deficient muscles, peroxisome proliferator-activated receptor gamma coactivator 1-α (PGC-1α), which regulates mitochondrial biogenesis and glucose homeostasis, is strongly down-regulated. Here we tested whether induction of mitochondrial biogenesis pharmacologically or by the overexpression of PGC-1α is sufficient to reverse the phenotype of mice deficient for mTORC1. We show that both approaches normalize mitochondrial function, such as oxidative capacity and expression of mitochondrial genes. However, they do not prevent or delay the progressive myopathy. In addition, we find that mTORC1 has a much stronger effect than PGC-1α on the glycogen content in muscle. This effect is based on the strong activation of PKB/Akt in mTORC1-deficient mice. We also show that activation of PKB/Akt not only affects glycogen synthesis but also diminishes glycogen degradation. Thus, our work provides strong functional evidence that mitochondrial dysfunction in mice with inactivated mTORC1 signaling is caused by the down-regulation of PGC-1α. However, our data also show that the impairment of mitochondria does not lead directly to the lethal myopathy.
Effectiveness of international environmental regimes: Existing knowledge, cutting-edge themes, and research strategies
Authors: Young Oran R.
Published: December 2011

International environmental regimes—especially those regimes articulated in multilateral environmental agreements—have been a subject of intense interest within the scientific community over the last three decades. However, there are substantial differences of opinion regarding the effectiveness of these governance systems or the degree to which they are successful in solving the problems leading to their creation. This article provides a critical review of the literature on this topic. It extracts and summarizes what is known about the effectiveness of environmental regimes in the form of a series of general and specific propositions. It identifies promising topics for consideration in the next phase of research in this field. Additionally, it comments on the research strategies available to pursue this line of analysis. The general conclusions are that international environmental regimes can and do make a difference, although often in conjunction with a number of other factors, and that a strategy of using a number of tools combined can help to improve understanding of the determinants of success.
The genomic binding sites of a noncoding RNA
Authors: Simon Matthew D. , Wang Charlotte I. , Kharchenko Peter V. , West Jason A. , Chapman Brad A. , Alekseyenko Artyom A. , Borowsky Mark L. , Kuroda Mitzi I. , Kingston Robert E.
Published: December 2011

Long noncoding RNAs (lncRNAs) have important regulatory roles and can function at the level of chromatin. To determine where lncRNAs bind to chromatin, we developed capture hybridization analysis of RNA targets (CHART), a hybridization-based technique that specifically enriches endogenous RNAs along with their targets from reversibly cross-linked chromatin extracts. CHART was used to enrich the DNA and protein targets of endogenous lncRNAs from flies and humans. This analysis was extended to genome-wide mapping of
roX2
, a well-studied ncRNA involved in dosage compensation in
Drosophila
. CHART revealed that
roX2
binds at specific genomic sites that coincide with the binding sites of proteins from the male-specific lethal complex that affects dosage compensation. These results reveal the genomic targets of
roX2
and demonstrate how CHART can be used to study RNAs in a manner analogous to chromatin immunoprecipitation for proteins.
Polycomb group proteins are required to couple seed coat initiation to fertilization
Authors: Roszak Pawel , Köhler Claudia
Published: December 2011

Seed development in flowering plants is initiated after a double fertilization event leading to the formation of zygotic embryo and endosperm tissues surrounded by the maternally derived seed coat. Although the seed coat does not take part in the fertilization process it develops immediately after fertilization, implicating a signaling mechanism from zygotic tissues to the surrounding maternal tissues. We addressed the question of the underlying mechanisms repressing seed coat development before fertilization and initiating seed coat development after fertilization by analyzing combinations of mutants that initiate seed development in the absence of fertilization. We discovered that seed coat development is actively repressed before fertilization by dosage-sensitive Polycomb group proteins acting in maternal tissues surrounding the female gametophyte. This repression is relieved after fertilization by a signal that is formed by the sexual endosperm. Fertilization is required for signal formation, as asexually formed endosperm fails to effectively initiate seed coat development in mutants with uncompromised maternal Polycomb group function. Mutants for the MADS-box transcription factor AGL62 initiate embryo and endosperm formation but fail to develop a seed coat, implicating
AGL62
expression in the endosperm as a requirement for signal initiation. Together, our results provide evidence that fertilization of the central cell generates a signal that relieves Polycomb group-mediated repression in the surrounding maternal tissues to initiate seed coat formation.
The unfolded protein response supports cellular robustness as a broad-spectrum compensatory pathway
Authors: Thibault Guillaume , Ismail Nurzian , Ng Davis T. W.
Published: December 2011

Stress pathways monitor intracellular systems and deploy a range of regulatory mechanisms in response to stress. One of the best-characterized pathways, the unfolded protein response (UPR), is responsible for maintaining endoplasmic reticulum (ER) homeostasis. The highly conserved Ire1 branch regulates hundreds of gene targets by activating a UPR-specific transcription factor. To understand how the UPR manages ER stress, a unique genetic approach was applied to reveal how the system corrects disequilibria. The data show that the UPR can address a wide range of dysfunctions that are otherwise lethal if not for its intervention. Transcriptional profiling of stress-alleviated cells shows that the program can be modulated, not just in signal amplitude, but also through differential target gene expression depending on the stress. The breadth of the functions mitigated by the UPR further supports its role as a major mechanism maintaining systems robustness.
A nonreplicating subunit vaccine protects mice against lethal Ebola virus challenge
Authors: Phoolcharoen Waranyoo , Dye John M. , Kilbourne Jacquelyn , Piensook Khanrat , Pratt William D. , Arntzen Charles J. , Chen Qiang , Mason Hugh S. , Herbst-Kralovetz Melissa M.
Published: December 2011

Ebola hemorrhagic fever is an acute and often deadly disease caused by Ebola virus (EBOV). The possible intentional use of this virus against human populations has led to design of vaccines that could be incorporated into a national stockpile for biological threat reduction. We have evaluated the immunogenicity and efficacy of an EBOV vaccine candidate in which the viral surface glycoprotein is biomanufactured as a fusion to a monoclonal antibody that recognizes an epitope in glycoprotein, resulting in the production of Ebola immune complexes (EICs). Although antigen–antibody immune complexes are known to be efficiently processed and presented to immune effector cells, we found that codelivery of the EIC with Toll-like receptor agonists elicited a more robust antibody response in mice than did EIC alone. Among the compounds tested, polyinosinic:polycytidylic acid (PIC, a Toll-like receptor 3 agonist) was highly effective as an adjuvant agent. After vaccinating mice with EIC plus PIC, 80% of the animals were protected against a lethal challenge with live EBOV (30,000 LD50of mouse adapted virus). Surviving animals showed a mixed Th1/Th2 response to the antigen, suggesting this may be important for protection. Survival after vaccination with EIC plus PIC was statistically equivalent to that achieved with an alternative viral vector vaccine candidate reported in the literature. Because nonreplicating subunit vaccines offer the possibility of formulation for cost-effective, long-term storage in biothreat reduction repositories, EIC is an attractive option for public health defense measures.
A small molecule differentiation inducer increases insulin production by pancreatic β cells
Authors: Dioum Elhadji M. , Osborne Jihan K. , Goetsch Sean , Russell Jamie , Schneider Jay W. , Cobb Melanie H.
Published: December 2011

New drugs for preserving and restoring pancreatic β-cell function are critically needed for the worldwide epidemic of type 2 diabetes and the cure for type 1 diabetes. We previously identified a family of neurogenic 3,5-disubstituted isoxazoles (Isx) that increased expression of neurogenic differentiation 1 (NeuroD1, also known as BETA2); this transcription factor functions in neuronal and pancreatic β-cell differentiation and is essential for insulin gene transcription. Here, we probed effects of Isx on human cadaveric islets and MIN6 pancreatic β cells. Isx increased the expression and secretion of insulin in islets that made little insulin after prolonged ex vivo culture and increased expression of neurogenic differentiation 1 and other regulators of islet differentiation and insulin gene transcription. Within the first few hours of exposure, Isx caused biphasic activation of ERK1/2 and increased bulk histone acetylation. Although there was little effect on histone deacetylase activity, Isx increased histone acetyl transferase activity in nuclear extracts. Reconstitution assays indicated that Isx increased the activity of the histone acetyl transferase p300 through an ERK1/2-dependent mechanism. In summary, we have identified a small molecule with antidiabetic activity, providing a tool for exploring islet function and a possible lead for therapeutic intervention in diabetes.
Ets transcription factor Pointed promotes the generation of intermediate neural progenitors in
Drosophila
larval brains
Authors: Zhu Sijun , Barshow Suzanne , Wildonger Jill , Jan Lily Yeh , Jan Yuh-Nung
Published: December 2011

Intermediate neural progenitor (INP) cells are transient amplifying neurogenic precursor cells generated from neural stem cells. Amplification of INPs significantly increases the number of neurons and glia produced from neural stem cells. In
Drosophila
larval brains, INPs are produced from type II neuroblasts (NBs,
Drosophila
neural stem cells), which lack the proneural protein Asense (Ase) but not from Ase-expressing type I NBs. To date, little is known about how Ase is suppressed in type II NBs and how the generation of INPs is controlled. Here we show that one isoform of the Ets transcription factor Pointed (Pnt), PntP1, is specifically expressed in type II NBs, immature INPs, and newly mature INPs in type II NB lineages. Partial loss of PntP1 in genetic mosaic clones or ectopic expression of the Pnt antagonist Yan, an Ets family transcriptional repressor, results in a reduction or elimination of INPs and ectopic expression of Ase in type II NBs. Conversely, ectopic expression of PntP1 in type I NBs suppresses Ase expression the NB and induces ectopic INP-like cells in a process that depends on the activity of the tumor suppressor Brain tumor. Our findings suggest that PntP1 is both necessary and sufficient for the suppression of Ase in type II NBs and the generation of INPs in
Drosophila
larval brains.
Biogenesis of a novel compartment for autophagosome-mediated unconventional protein secretion
Authors: Bruns Caroline , McCaffery J. Michael , Curwin Amy J. , Duran Juan M. , Malhotra Vivek
Published: December 2011

The endoplasmic reticulum (ER)–Golgi-independent, unconventional secretion of Acb1 requires many different proteins. They include proteins necessary for the formation of autophagosomes, proteins necessary for the fusion of membranes with the endosomes, proteins of the multivesicular body pathway, and the cell surface target membrane SNARE Sso1, thereby raising the question of what achieves the connection between these diverse proteins and Acb1 secretion. In the present study, we now report that, upon starvation in Saccharomyces cerevisiae, Grh1 is collected into unique membrane structures near Sec13-containing ER exit sites. Phosphatidylinositol 3 phosphate, the ESCRT (endosomal sorting complex required for transport) protein Vps23, and the autophagy-related proteins Atg8 and Atg9 are recruited to these Grh1-containing membranes, which lack components of the Golgi apparatus and the endosomes, and which we call a novel compartment for unconventional protein secretion (CUPS). We describe the cellular proteins required for the biogenesis of CUPS, which we believe is the sorting station for Acb1’s release from the cells.
Subunit-dependent modulation of septin assembly: Budding yeast septin Shs1 promotes ring and gauze formation
Authors: Garcia Galo , Bertin Aurelie , Li Zhu , Song Yi , McMurray Michael A. , Thorner Jeremy , Nogales Eva
Published: December 2011

Septins are conserved guanosine triphosphate–binding cytoskeletal proteins involved in membrane remodeling. In budding yeast, five mitotic septins (Cdc3, Cdc10, Cdc11, Cdc12, and Shs1), which are essential for cytokinesis, transition during bud growth from a patch to a collar, which splits into two rings in cytokinesis and is disassembled before the next cell cycle. Cdc3, Cdc10, Cdc11, and Cdc12 form an apolar octameric rod with Cdc11 at each tip, which polymerizes into straight paired filaments. We show that Shs1 substitutes for Cdc11, resulting in octameric rods that do not polymerize into filaments but associate laterally, forming curved bundles that close into rings. In vivo, half of shs1Δ mutant cells exhibit incomplete collars and disrupted neck filaments. Importantly, different phosphomimetic mutations in Shs1 can either prevent ring formation or promote formation of a gauzelike meshwork. These results show that a single alternative terminal subunit is sufficient to confer a distinctive higher-order septin ultrastructure that can be further regulated by phosphorylation.
TAK1 in brain endothelial cells mediates fever and lethargy
Authors: Ridder Dirk A. , Lang Ming-Fei , Salinin Sergei , Röderer Jan-Peter , Struss Marcel , Maser-Gluth Christiane , Schwaninger Markus
Published: December 2011

Systemic inflammation affects the brain, resulting in fever, anorexia, lethargy, and activation of the hypothalamus–pituitary–adrenal axis. How peripheral inflammatory signals reach the brain is still a matter of debate. One possibility is that, in response to inflammatory stimuli, brain endothelial cells in proximity to the thermoregulatory centers produce cyclooxygenase 2 (COX-2) and release prostaglandin E2, causing fever and sickness behavior. We show that expression of the MAP kinase kinase kinase TAK1 in brain endothelial cells is needed for interleukin 1β (IL-1β)–induced COX-2 production. Exploiting the selective expression of the thyroxine transporter Slco1c1 in brain endothelial cells, we generated a mouse line allowing inducible deletion of Tak1 specifically in brain endothelium. Mice lacking the Tak1 gene in brain endothelial cells showed a blunted fever response and reduced lethargy upon intravenous injection of the endogenous pyrogen IL-1β. In conclusion, we demonstrate that TAK1 in brain endothelial cells induces COX-2, most likely by activating p38 MAPK and c-Jun, and is necessary for fever and sickness behavior.
Pruritus Vulvae
Authors: Thoroughgood Vasandhara
Published: December 2011

Pruritus vulvae refers to persistent vulval itching and affects up to 1 in 10 women at some point in their life. Frequently, there is a delay in seeking medical advice, and women often self-medicate with over-the-counter preparations before seeing their GP. These preparations may exacerbate the problem further. As pruritus vulvae has a wide range of causes, a careful history and examination are essential. Management involves both general measures to reduce itching as well as those targeted at the specific cause. This article summarizes the common causes of pruritus vulvae and an approach to assessment and management.
Detecting areas of endemism with a taxonomically diverse data set: plants, mammals, reptiles, amphibians, birds, and insects from Argentina
Authors: Szumik Claudia , Aagesen Lone , Casagranda Dolores , Arzamendia Vanesa , Baldo Diego , Claps Lucía E. , Cuezzo Fabiana , Díaz Gómez Juan M. , Di Giacomo Adrián , Giraudo Alejandro , Goloboff Pablo , Gramajo Cecilia , Kopuchian Cecilia , Kretzschmar Sonia , Lizarralde Mercedes , Molina Alejandra , Mollerach Marcos , Navarro Fernando , Nomdedeu Soledad , Panizza Adela , Pereyra Verónica V. , Sandoval María , Scrocchi Gustavo , Zuloaga Fernando O.
Published: December 2011

The idea of an area of endemism implies that different groups of plants and animals should have largely coincident distributions. This paper analyses an area of 1152 000 km2, between parallels 21 and 32°S and meridians 70 and 53°W to examine whether a large and taxonomically diverse data set actually displays areas supported by different groups. The data set includes the distribution of 805 species of plants (45 families), mammals (25 families), reptiles (six families), amphibians (five families), birds (18 families), and insects (30 families), and is analysed with the optimality criterion (based on the notion of endemism) implemented in the program NDM/VNDM. Almost 50% of the areas obtained are supported by three or more major groups; areas supported by fewer major groups generally contain species from different genera, families, or orders.

© The Willi Hennig Society 2011.
Downregulating hypoxia‐inducible factor‐2α improves the efficacy of doxorubicin in the treatment of hepatocellular carcinoma
Authors: He Changjun , Sun Xue‐Pu , Qiao Haiquan , Jiang Xian , Wang Dongdong , Jin Xiangguo , Dong Xuesong , Wang Jizhou , Jiang Hongchi , Sun Xueying
Published: December 2011

The hypoxic microenvironment inside solid tumors, including hepatocellular carcinoma (HCC), is a major cause of tumor resistance to chemotherapy. The recently identified hypoxia‐inducible factor (HIF)‐2 executes the hypoxia response. Its expression feature and transcriptional targets indicate a possible dominance of HIF‐2 in regulating genes in HCC. The aim of the present study was to determine whether transfection of siRNA targeting HIF‐2α could enhance the efficacy of doxorubicin, the most commonly used drug in the treatment of HCC. Transfection of HIF‐2 siRNA into human HCC cells downregulated the expression of HIF‐2α, vascular endothelial growth factor (VEGF), transforming growth factor (TGF)‐α, and cyclin D1, but had little effect on the expression of HIF‐1α, fms‐related tyrosine kinase‐1 (Flt‐1), the glucose transporter (GLUT)‐1, and lactate dehydrogenase A (LDHA). Doxorubicin itself only downregulated VEGF expression. Furthermore, HIF‐2 siRNA inhibited proliferation, induced cell cycle arrest at the G0/G1 phase, and acted synergistically with doxorubicin to inhibit the growth of human HCC cells in vitro. Transfection of HIF‐2 siRNA also downregulated tumoral expression of HIF‐2α, VEGF, TGF‐α, and cyclin D1 in vivo, and acted synergistically with doxorubicin to suppress the growth of HepG2 tumors established in immunodeficient mice by inhibiting cell proliferation, tumor angiogenesis and microvessel perfusion. The results of the present study suggest that targeting HIF‐2α with siRNA warrants investigation as a potential strategy to enhance the efficacy of doxorubicin in the treatment of HCC. (Cancer Sci 2012; 103: 528–534)
Carbon monoxide, generated by heme oxygenase‐1, mediates the enhanced permeability and retention effect in solid tumors
Authors: Fang Jun , Qin Haibo , Nakamura Hideaki , Tsukigawa Kenji , Shin Takashi , Maeda Hiroshi
Published: December 2011

The enhanced permeability and retention (EPR) effect is a unique pathophysiological phenomenon of solid tumors that sees biocompatible macromolecules (>40 kDa) accumulate selectively in the tumor. Various factors have been implicated in this effect. Herein, we report that heme oxygenase‐1 (HO‐1; also known as heat shock protein 32) significantly increases vascular permeability and thus macromolecular drug accumulation in tumors. Intradermal injection of recombinant HO‐1 in mice, followed by i.v. administration of a macromolecular Evans blue–albumin complex, resulted in dose‐dependent extravasation of Evans blue–albumin at the HO‐1 injection site. Almost no extravasation was detected when inactivated HO‐1 or a carbon monoxide (CO) scavenger was injected instead. Because HO‐1 generates CO, these data imply that CO plays a key role in vascular leakage. This is supported by results obtained after intratumoral administration of a CO‐releasing agent (tricarbonyldichlororuthenium(II) dimer) in the same experimental setting, specifically dose‐dependent increases in vascular permeability plus augmented tumor blood flow. In addition, induction of HO‐1 in tumors by the water‐soluble macromolecular HO‐1 inducer pegylated hemin significantly increased tumor blood flow and Evans blue–albumin accumulation in tumors. These findings suggest that HO‐1 and/or CO are important mediators of the EPR effect. Thus, anticancer chemotherapy using macromolecular drugs may be improved by combination with an HO‐1 inducer, such as pegylated hemin, via an enhanced EPR effect. (Cancer Sci 2012; 103: 535–541)
Benthic resources are the key to Daphnia middendorffiana survival in a high arctic pond
Authors: CAZZANELLI MATTEO , FORSSTRÖM LAURA , RAUTIO MILLA , MICHELSEN ANDERS , CHRISTOFFERSEN KIRSTEN S.
Published: December 2011

1. Shallow arctic lakes and ponds have simple and short food webs, but large uncertainties remain about benthic–pelagic links in these systems. We tested whether organic matter of benthic origin supports zooplankton biomass in a pond in NE Greenland, using stable isotope analysis of carbon and nitrogen in the pond itself and in a 13C‐enrichment enclosure experiment. In the latter, we manipulated the carbon isotope signature of benthic algae to enhance its isotopic discrimination from other potential food sources for zooplankton.

2. The cladoceran Daphnia middendorffiana responded to the 13C‐enrichment of benthic mats with progressively increasing δ13C values, suggesting benthic feeding. Stable isotope analysis also pointed towards a negligible contribution of terrestrial carbon to the diet of D. middendorffiana. This agreed with the apparent dominance of autochthonous dissolved organic matter in the pond revealed by analysis of coloured dissolved organic matter.

3. Daily net production by phytoplankton in the pond (18 mg C m−2 day−1) could satisfy only up to half of the calculated minimum energy requirements of D. middendorffiana (35 mg C m−2 day−1), whereas benthic primary production alone (145 mg C m−2 day−1) was more than sufficient.

4. Our findings highlight benthic primary production as a major dietary source for D. middendorffiana in this system and suggest that benthic organic matter may play a key role in sustaining pelagic secondary production in such nutrient‐limited high arctic ponds.
The effect of natural substrates on jump height in click‐beetles
Authors: Ribak Gal , Reingold Sonia , Weihs Daniel
Published: December 2011

1. Inverted click‐beetles (Elateridae) jump to right themselves, providing enough energy to launch the body many body lengths into the air.

2. We tested whether the apparently redundant jump energy could be an adaptation for jumping from compliant surfaces that absorb energy, in the natural habitat. Jump height was measured in beetles jumping from natural substrates and from an apparatus we designed, allowing them to adjust the level of jump energy attenuated by the substrate.

3. Jump height was dramatically reduced (by c. 75%) when jumping from leaves that covered approximately half of the study site. In the remaining area, jumping for righting was either not required or not substantially attenuated. Therefore, the available power for jumping results in low jumps that are barely sufficient for righting when jumping from compliant surfaces covering c. 50% of the natural habitat.

4. The decrease in jump height was correlated with the amount of work absorbed by the substrate. We therefore conclude that the beetles do not adjust the muscle work invested in jumping to adjust for changes in substrate stiffness.

5. Scaling considerations of the jumping mechanics suggest that substrate compliance becomes a bigger problem for larger beetles.

6. The effect of substrate compliance needs to be taken into account while addressing the functional ecology of jumping animals.
Interactive responses of old‐field plant growth and composition to warming and precipitation
Authors: Hoeppner Susanne S. , Dukes Jeffrey S.
Published: December 2011

As Earth's atmosphere accumulates carbon dioxide (CO2) and other greenhouse gases, Earth's climate is expected to warm and precipitation patterns will likely change. The manner in which terrestrial ecosystems respond to climatic changes will in turn affect the rate of climate change. Here we describe responses of an old‐field herbaceous community to a factorial combination of four levels of warming (up to 4 °C) and three precipitation regimes (drought, ambient and rain addition) over 2 years. Warming suppressed total production, shoot production, and species richness, but only in the drought treatment. Root production did not respond to warming, but drought stimulated the growth of deeper (> 10 cm) roots by 121% in 1 year. Warming and precipitation treatments both affected functional group composition, with C4 grasses and other annual and biennial species entering the C3 perennial‐dominated community in ambient rainfall and rain addition treatments as well as in warmed treatments. Our results suggest that, in this mesic system, expected changes in temperature or large changes in precipitation alone can alter functional composition, but they have little effect on total herbaceous plant growth. However, drought limits the capacity of the entire system to withstand warming. The relative insensitivity of our study system to climate suggests that the herbaceous component of old‐field communities will not dramatically increase production in response to warming or precipitation change, and so it is unlikely to provide either substantial increases in forage production or a meaningful negative feedback to climate change later this century.
Robust heat‐inducible gene expression by two endogenous hsp70‐derived promoters in transgenic Aedes aegypti
Authors: Carpenetti T. L. G. , Aryan A. , Myles K. M. , Adelman Z. N.
Published: December 2011

Aedes aegypti is an important vector of the viruses that cause dengue fever, dengue haemorrhagic fever and yellow fever. Reverse genetic approaches to the study of gene function in this mosquito have been limited by the lack of a robust inducible promoter to allow precise temporal control over a protein‐encoding or hairpin RNA transgene. Likewise, investigations into the molecular and biochemical basis of vector competence would benefit from the ability to activate an antipathogen molecule at specific times during infection. We have characterized the ability of genomic sequences derived from two Ae. aegypti heat shock protein 70 (hsp70) genes to drive heat‐inducible expression of a reporter in both transient and germline transformation contexts. AaHsp70‐luciferase transcripts accumulated specifically after heat shock, and displayed a pattern of rapid induction and decay similar to endogenous AaHsp70 genes. Luciferase expression in transgenic Ae. aegypti increased by ∼25–50‐fold in whole adults by 4 h after heat‐shock, with significant activity (∼20‐fold) remaining at 24 h. Heat‐induced expression was even more dramatic in midgut tissues, with one strain showing a ∼2500‐fold increase in luciferase activity. The AaHsp70 promoters described could be valuable for gene function studies as well as for the precise timing of the expression of antipathogen molecules.
Factors influencing Dutch practice nurses’ intention to adopt a new smoking cessation intervention
Authors: Leitlein Lisa , Smit Eline Suzanne , de Vries Hein , Hoving Ciska
Published: December 2011

leitlein l., smit e.s., de vries h. & hoving c. (2012) Factors influencing Dutch practice nurses’ intention to adopt a new smoking cessation intervention. Journal of Advanced Nursing68(10), 2185–2194.

Aims.  This article is a report of a study that aimed to identify factors influencing practice nurses’ and nurse practitioners’ intention to adopt a new smoking cessation intervention.

Background.  Although effective smoking cessation interventions exist and practice nurses can offer a considerable resource in advertising patients to quit smoking, due to several reasons the majority of practice nurses do not implement these interventions.

Methods.  A cross‐sectional study was undertaken among Dutch practice nurses and nurse practitioners working in general practices (n = 139) using electronic questionnaires. Data were collected from January until March in 2009. T‐tests were used to compare adopters with non‐adopters about their predisposing and motivational factors. Logistic regression analyses were conducted to assess the variation in intention explained by these factors.

Results.  The majority of practice nurses did not intend to adopt the new intervention (n = 85; 61·2%). More practice nurses than nurse practitioners intended to adopt the intervention. Attitude and perceived social norms were found to be positively correlated with the intention to adopt the intervention whereas satisfaction with current smoking cessation activities was found to be negatively correlated.

Conclusion.  Important associations were found between profession, attitude, social norms and satisfaction, and the intention to adopt the new smoking cessation intervention. Practice nurses who do not intend to adopt need to be persuaded of the advantages of adopting. Perceived social norms need to be restructured and before presenting the intervention to a general practice current smoking cessation activities should be determined to increase the intervention’s compatibility with these current practices.
Leaf ageing promotes the shift in defence tactics in Mallotus japonicus from direct to indirect defence
Authors: Yamawo Akira , Suzuki Nobuhiko , Tagawa Jun , Hada Yoshio
Published: December 2011

1. Most plant species rely upon multiple lines of defence that develop or change functions with leaf age. To date, the effects of leaf age on multiple defence traits have been insufficiently elucidated. For Mallotus japonicus (Euphorbiaceae), we report a shift from direct to indirect defence against herbivory. That shift occurs gradually during leaf ageing.

2. First, the densities of trichomes and pellucid dots, the numbers of extrafloral nectaries (EFNs) and pearl bodies, and the number of ants on leaves of M. japonicus were examined in the field at weekly intervals. Secondly, herbivore species and the degree of herbivory were examined. Thirdly, the effects of ants on herbivore exclusion were investigated experimentally in the field. Finally, to confirm the effectiveness of trichomes and pellucid dots for defence against two herbivore species [the adult flea beetle, Aphthona strigosa (Coleoptera: Chrysomelidae), and the inchworm, Ascotis selenaria (Lepidoptera: Geometridae)], both young and middle‐aged leaves were tested using laboratory bioassay.

3. On newly emerged leaves, densities of trichomes and pellucid dots were extremely high, but they decreased rapidly with leaf age. The respective quantities of EFNs that were actually secreting nectar, the pearl bodies, and the ants on middle‐aged leaves were greater than those on leaves of other ages. On M. japonicus, we found 11 herbivorous insects, among which Ap. strigosa and As. selenaria were the principal herbivores.

4. The damaged leaf areas of ant‐excluded plants were much larger than those of control plants. Most herbivory was attributable to As. selenaria. Laboratory bioassay revealed that against Ap. strigosa and small As. selenaria larvae, trichomes and pellucid dots in young leaves functioned well, although those in middle‐aged leaves did not.

5. Synthesis. Young M. japonicus leaves are defended against herbivores through the use of direct defence traits such as trichomes and pellucid dots. However, the plant uses indirect defence traits for middle‐aged leaves. This shift from direct defence to indirect defence with leaf ageing supports the ‘optimal defence theory’: plants have evolved multiple defence traits to maximize their fitness.
Detailed three‐dimensional visualization of resilin in the exoskeleton of arthropods using confocal laser scanning microscopy
Authors: MICHELS J. , GORB S.N.
Published: December 2011

Resilin is a rubber‐like protein found in the exoskeleton of arthropods. It often contributes large proportions to the material of certain structures in movement systems. Accordingly, the knowledge of the presence and distribution of resilin is essential for the understanding of the functional morphology of these systems. Because of its specific autofluorescence, resilin can be effectively visualized using fluorescence microscopy. However, the respective excitation maximum is in the UV range, which is not covered by the lasers available in most of the modern commercial confocal laser scanning microscopes. The goal of this study was to test the potential of confocal laser scanning microscopy (CLSM) in combination with a 405 nm laser to visualize and analyse the presence and distribution of resilin in arthropod exoskeletons. The results clearly show that all resilin‐dominated structures, which were visualized successfully using wide‐field fluorescence microscopy (WFM) and a ‘classical’ UV excitation, could also be visualized efficiently with the proposed CLSM method. Furthermore, with the application of additional laser lines CLSM turned out to be very appropriate for studying differences in the material composition within arthropod exoskeletons in great detail. As CLSM has several advantages over WFM with respect to detailed morphological imaging, the application of the proposed CLSM method may reveal new information about the micromorphology and material composition of resilin‐dominated exoskeleton structures leading to new insights into the functional morphology and biomechanics of arthropods.
Dehydroepiandrosterone Sulphate: Action and Mechanism in the Brain
Authors: Dong Y. , Zheng P.
Published: December 2011

Dehydroepiandrosterone sulphate (DHEAS) is synthesised from dehydroepiandrosterone by the enzyme sulphotransferase. DHEAS is one of the most important neurosteroids in the brain. The concentration of DHEAS in the brain is sometimes higher than peripheral system. At the cellular level, DHEAS has been shown to modulate a variety of synaptic transmission, including cholinergic, GABAergic dopaminergic and glutamatergic synaptic transmission. In addition to the effect on the release of a number of neurotransmitters, DHEAS could also modulate the activity of postsynaptic receptors. DHEAS has been found to have multiple important effects on brain functions, such as memory enhancing, antidepressant and anxiolytic effects, and may have relationships with many brain diseases.
Two distinct RNA‐dependent RNA polymerases are required for initiation and amplification of RNA silencing in the basal fungus Mucor circinelloides
Authors: Calo Silvia , Nicolás Francisco E. , Vila Ana , Torres‐Martínez Santiago , Ruiz‐Vázquez Rosa M.
Published: December 2011

RNA‐dependent RNA polymerases (RdRPs) play key roles in the RNA silencing pathway in a number of organisms. They have been involved in the production of double‐stranded RNA (dsRNA) molecules that initiate the silencing mechanism as well as in the amplification of the silencing signal. The roles of RdRPs from fungi in these processes are poorly described compared with other eukaryotes. RNA silencing in the zygomycete Mucor circinelloides exhibits uncommon features, such as induction by self‐replicative sense transgenes and an amplification process associated with two size classes of antisense small interfering RNAs (siRNAs). To investigate the function of fungal RdRP proteins in initiation and amplification of silencing we have cloned and characterized two different rdrp genes in M. circinelloides. Functional analysis of rdrp‐ disruption mutants indicates that rdrp‐1 is essential for initiation of silencing by sense transgenes by producing antisense RNA transcripts derived from the transgene, but it is not necessary for amplification of the silencing signal, whereas rdrp‐2 is required for efficient accumulation of the two different classes of secondary siRNAs regardless the nature of the trigger. Our results provide evidence for a functional diversification of M. circinelloides rdrp genes in different steps of the same RNA silencing pathway.
Gene expression is differently affected by pimecrolimus and betamethasone in lesional skin of atopic dermatitis
Authors: Jensen J. M. , Scherer A. , Wanke C. , Bräutigam M. , Bongiovanni S. , Letzkus M. , Staedtler F. , Kehren J. , Zuehlsdorf M. , Schwarz T. , Weichenthal M. , Fölster‐Holst R. , Proksch E.
Published: December 2011

To cite this article: Jensen JM, Scherer A, Wanke C, Bräutigam M, Bongiovanni S, Letzkus M, Staedtler F, Kehren J, Zuehlsdorf M, Schwarz T, Weichenthal M, Fölster‐Holst R, Proksch E. Gene expression is differently affected by pimecrolimus and betamethasone in lesional skin of atopic dermatitis. Allergy 2012; 67: 413–423.

Background:  Topical corticosteroids and calcineurin inhibitors are well‐known treatments of atopic dermatitis (AD) but differ in their efficacy and side effects. We recently showed that betamethasone valerate (BM) although clinically more efficient impaired skin barrier repair in contrast to pimecrolimus in AD.

Objective:  This study elucidates the mode of action of topical BM and pimecrolimus cream in AD.

Methods:  Lesional AD skin samples after topical treatment with either BM or pimecrolimus were subjected to gene expression profile analysis.

Results:  Betamethasone valerate resulted in a significant reduction in mRNA levels of genes encoding markers of immune cells and inflammation, dendritic cells, T cells, cytokines, chemokines, and serine proteases, whereas pimecrolimus exerted minor effects only. This corroborates the clinical finding that BM reduces inflammation more effectively than pimecrolimus. Genes encoding molecules important for skin barrier function were differently affected. Both BM and pimecrolimus normalized the expression of filaggrin and loricrin. BM, but not pimecrolimus, significantly reduced the expression of rate‐limiting enzymes for lipid synthesis and the expression of involucrin and small proline‐rich proteins, which covalently bind ceramides. This may explain the lack of restoration of functional stratum corneum layers observed after BM treatment.

Conclusion:  The gene expression profiles are consistent with our previous findings that corticosteroids may exert a more potent anti‐inflammatory effect but may impair the restoration of the skin barrier. Corticosteroids are still the main treatment for severe and acutely exacerbated AD; pimecrolimus may be preferable for long‐term treatment and stabilization.