bluuebunny/crossref_metadata_2025_split huggingface dataset:
Role of bacteriophage SPP1 tail spike protein gp21 on host cell receptor binding and trigger of phage DNA ejection
Authors: Vinga Inês , Baptista Catarina , Auzat Isabelle , Petipas Isabelle , Lurz Rudi , Tavares Paulo , Santos Mário A. , São‐José Carlos 
Published: December 2011

SummaryBacteriophages recognize and bind specific receptors to infect suitable hosts. Bacteriophage SPP1 targets at least two receptors of the Bacillus subtilis cell envelope, the glucosylated wall teichoic acids and the membrane protein YueB. Here, we identify a key virion protein for YueB binding and for the trigger of DNA ejection. Extracts from B. subtilis‐infected cells applied to a YueB affinity matrix led to preferential capturing of gp21 from SPP1. To assess the significance of this interaction, we isolated mutant phages specifically affected in YueB binding. The mutants exhibited a very low inactivation rate and a strong defect to eject DNA when challenged with YueB. The phenotype correlated with presence of a single amino acid substitution in the gp21 carboxyl terminus, defining a region involved in YueB binding. Immunoelectron microscopy located the gp21 N‐terminus in the SPP1 cap and probably in the adjacent tail spike region whereas the gp21 C‐terminus was mapped further down in the spike structure. Antibodies against this part of gp21 interfered with the interaction of YueB with SPP1 and triggered DNA ejection. The gp21 C‐terminal region thus plays a central role in two early key events that commit the virus to deliver its genome into host cells.
Brh2 domain function distinguished by differential cellular responses to DNA damage and replication stress
Authors: Kojic Milorad , Holloman William K. 
Published: December 2011

SummaryMutants of the fungus Ustilago maydis defective in the RecQ helicase Blm are highly sensitive to killing by the DNA replication stressor hydroxyurea. This sensitivity or toxicity is dependent on the homologous recombination (HR) system and apparently results from formation of dead‐end HR DNA intermediates. HU toxicity can be suppressed by deletion of the gene encoding Brh2, the BRCA2 orthologue that serves to regulate HR by mediating Rad51 filament formation on single‐stranded DNA. Brh2 harbours two different DNA‐binding domains that contribute to HR function. DNA‐binding activity from a single domain is sufficient to provide Brh2 functional activity in HR, but to enable HU‐induced killing two functional DNA‐binding domains must be present. Despite this stringent requirement for dual functioning domains, the source of DNA‐binding domains is less critical in that heterologous domains can substitute for the native endogenous ones. The results suggest a model in which the nature of the DNA lesion is an important determinant in the functional response of Brh2 action.
A kinetoplastid‐specific kinesin is required for cytokinesis and for maintenance of cell morphology in Trypanosoma brucei
Authors: Hu Liu , Hu Huiqing , Li Ziyin 
Published: December 2011

SummaryKinesins are motor‐based transport proteins that play diverse roles in various cellular processes. The trypanosome genome lacks the homologues of many conserved mitotic kinesins, but encodes a number of trypanosome‐specific kinesins with unknown function. Here, we report the biochemical and functional characterization of TbKIN‐C, a trypanosome‐specific kinesin, which was initially identified through an RNAi screen for cytokinesis genes in T. brucei. TbKIN‐C possesses in vitro ATPase activity and associates with cytoskeletal tubulin microtubules in vivo. It is distributed throughout the cytoskeleton with a focal enrichment at the posterior end of the cell during early cell cycle stages. RNAi of TbKIN‐C resulted in distorted cell shape with an elongated posterior filled with tyrosinated tubulin microtubules. Silencing of TbKIN‐C impaired the segregation of organelles and cytoskeletal structures and led to detachment of the new flagellum and a small portion of the cytoplasm. We also show that RNAi of TbKIN‐C compromised cytokinesis and abolished the trans‐localization of TbCPC1, a subunit of the chromosomal passenger complex, from the central spindle to the initiation site of cytokinesis. Our results suggest an essential role of TbKIN‐C in maintaining cell morphology, likely through regulating microtubule dynamics at the posterior end of the cell.
First palaeomagnetic dating of ferricrete in New Caledonia: new insight on the morphogenesis and palaeoweathering of ‘Grande Terre’
Authors: Sevin Brice , Ricordel‐Prognon Caroline , Quesnel Florence , Cluzel Dominique , Lesimple Stéphane , Maurizot Pierre 
Published: December 2011

Terra Nova, 24, 77–85, 2012AbstractComparing palaeolatitudes estimated from remanent magnetization data of ferricrete developed over laterite at two sites (Goro and Tiébaghi) against the apparent polar wandering path of Australia provides new time constraints for the peridotite weathering in New Caledonia. The Tiébaghi Massif of the West Coast klippes displays a single episode of ferricrete development during latest Oligocene times. By contrast, the Goro site in the southern part of the ‘Massif du Sud' reveals a more complex history with several episodes of ferricrete development from latest Oligocene to Pliocene–Quaternary times. These data have made it possible to constrain the post‐obduction geodynamics and associated morphogenesis of New Caledonia since related uplift probably prevented regolith development until latest Oligocene times. Moreover, the later uplift and deep erosion of the West Coast klippes during the Early Miocene probably prevented further regolith preservation.
Transgenic expression of human heme oxygenase‐1 in pigs confers resistance against xenograft rejection during ex vivo perfusion of porcine kidneys
Authors: Petersen Björn , Ramackers Wolf , Lucas‐Hahn Andrea , Lemme Erika , Hassel Petra , Queißer Anna‐Lisa , Herrmann Doris , Barg‐Kues Brigitte , Carnwath Joseph W. , Klose Johannes , Tiede Andreas , Friedrich Lars , Baars Wiebke , Schwinzer Reinhard , Winkler Michael , Niemann Heiner 
Published: December 2011

Petersen B, Ramackers W, Lucas‐Hahn A, Lemme E, Hassel P, Queißer A‐L, Herrmann D, Barg‐Kues B, Carnwath JW, Klose J, Tiede A, Friedrich L, Baars W, Schwinzer R, Winkler M, Niemann H. Transgenic expression of human heme oxygenase‐1 in pigs confers resistance against xenograft rejection during ex vivo perfusion of porcine kidneys. Xenotransplantation 2011; 18: 355–368. © 2011 John Wiley & Sons A/S.Abstract:Background:  The major immunological hurdle to successful porcine‐to‐human xenotransplantation is the acute vascular rejection (AVR), characterized by endothelial cell (EC) activation and perturbation of coagulation. Heme oxygenase‐1 (HO‐1) and its derivatives have anti‐apoptotic, anti‐inflammatory effects and protect against reactive oxygen species, rendering HO‐1 a promising molecule to control AVR. Here, we report the production and characterization of pigs transgenic for human heme oxygenase‐1 (hHO‐1) and demonstrate significant protection in porcine kidneys against xenograft rejection in ex vivo perfusion with human blood and transgenic porcine aortic endothelial cells (PAEC) in a TNF‐α‐mediated apoptosis assay.Methods:  Transgenic and non‐transgenic PAEC were tested in a TNF‐α‐mediated apoptosis assay. Expression of adhesion molecules (ICAM‐1, VCAM‐1, and E‐selectin) was measured by real‐time PCR. hHO‐1 transgenic porcine kidneys were perfused with pooled and diluted human AB blood in an ex vivo perfusion circuit. MHC class‐II up‐regulation after induction with IFN‐γ was compared between wild‐type and hHO‐1 transgenic PAEC.Results:  Cloned hHO‐1 transgenic pigs expressed hHO‐1 in heart, kidney, liver, and in cultured ECs and fibroblasts. hHO‐1 transgenic PAEC were protected against TNF‐α‐mediated apoptosis. Real‐time PCR revealed reduced expression of adhesion molecules like ICAM‐1, VCAM‐1, and E‐selectin. These effects could be abrogated by the incubation of transgenic PAECs with the specific HO‐1 inhibitor zinc protoporphorine IX (Zn(II)PPIX, 20 μm). IFN‐γ induced up‐regulation of MHC class‐II molecules was significantly reduced in PAECs from hHO‐1 transgenic pigs. hHO‐1 transgenic porcine kidneys could successfully be perfused with diluted human AB‐pooled blood for a maximum of 240 min (with and without C1 inh), while in wild‐type kidneys, blood flow ceased after ∼60 min. Elevated levels of d‐Dimer and TAT were detected, but no significant consumption of fibrinogen and antithrombin was determined. Microthrombi could not be detected histologically.Conclusions:  These results are encouraging and warrant further studies on the biological function of heme oxygenase‐I expression in hHO‐1 transgenic pigs in the context of xenotransplantation.
Protection of porcine endothelial cells against apoptosis with interleukin‐4
Authors: Black Sylvester M. , Benson Barbara A. , Idossa Damé , Vercellotti Gregory M. , Dalmasso Agustin P. 
Published: December 2011

Black SM, Benson BA, Idossa D, Vercellotti GM, Dalmasso AP. Protection of porcine endothelial cells against apoptosis with interleukin‐4. Xenotransplantation 2011; 18: 343–354. © 2011 John Wiley & Sons A/S.Abstract:Background: Apoptosis is crucial for tissue development and homeostasis, and insufficient apoptosis is pivotal in cancer pathogenesis. Apoptosis may also be important in tissue injury and in this case, it is of interest to induce protection against apoptosis. In organ transplantation, apoptosis has been implicated in acute vascular rejection (AVR); in xenotransplantation, the inducers of apoptosis of relevance in AVR, such as tumor necrosis factor‐α (TNF‐α), also cause endothelial cell (EC) activation. We have previously shown that interleukin (IL)‐4 and IL‐13 induced protection in porcine ECs against activation and apoptosis triggered by TNF‐α. Now we define signaling processes activated by IL‐4 in porcine ECs and mechanisms required for IL‐4‐induced protection against apoptosis.Methods: Porcine aortic ECs were used as primary cultures or as virus‐induced immortalized cells derived from galactosyl transferase‐deficient (Gal−/−) or wild‐type pigs. ECs were stimulated with porcine IL‐4, either extrinsically or transduced with recombinant adenovirus (adeno) IL‐4, and analyzed using immunoblotting. Apoptosis was induced with TNF‐α plus cycloheximide and assessed using neutral red uptake or flow cytometry. The role of various signaling proteins in IL‐4‐induced protection was established using pharmacologic inhibitors and siRNA downregulation of protein expression.Results: IL‐4 induced similar degrees of phosphorylation of STAT6 in all 3 types of ECs, and STAT6 was phosphorylated through Jak3. IL‐4 induced phosphorylation of Bad through Jak3. Stimulation of ECs with IL‐4 caused protection of ECs against apoptosis with an absolute requirement of Jak3/STAT6 activation and major participation of mammalian target of rapamycin complex 2 (mTORC2), Akt, and extracellular signal‐regulated kinase 1/2. IL‐4 caused no increase in EC levels of protective proteins hemoxygenase‐1, inhibitor of apoptosis protein, heat shock protein 70, Bcl‐2, and Bcl‐xL. ECs transduced with adenoIL‐4 exhibited strong and durable protection from apoptosis. Gal−/−ECs were as susceptible to induction of protection with IL‐4 as wild‐type ECs.Conclusions: IL‐4 induces activation of Jak3/STAT6 and phosphorylation of Bad in porcine ECs, ultimately resulting in effective protection of the ECs from apoptosis. Delineation of downstream signals activated by IL‐4 that are required for induction of protection suggests possible sites of intervention to design effective therapeutic agents. This is of interest because substances such as IL‐4 have pleiotropic effects and cannot be used directly due to potential deleterious effects. Inducing resistance to apoptosis in porcine vascular endothelium may be important to facilitate xenograft survival and accommodation.
Thrombocytopenia after pig‐to‐baboon liver xenotransplantation: where do platelets go?
Authors: Ezzelarab Mohamed , Ekser Burcin , Gridelli Bruno , Iwase Hayato , Ayares David , Cooper David K.C. 
Published: December 2011

Ezzelarab M, Ekser B, Gridelli B, Iwase H, Ayares D, Cooper DKC. Thrombocytopenia after pig‐to‐baboon liver xenotransplantation: where do platelets go? Xenotransplantation 2011; 18: 320–327. © 2011 John Wiley & Sons A/S.Abstract:Background:  In baboons with orthotopic pig liver xenografts, profound thrombocytopenia was observed within 1 h after reperfusion. Assessment of the fate of platelets may shed light on the underlying mechanisms leading to thrombocytopenia and may allow preventive therapies to be introduced.Methods:  Platelet–white blood cell (WBC) aggregation was studied in two baboons that received orthotopic liver xenografts from α1,3‐galactosyltransferase gene‐knockout pigs transgenic for human CD46 (GTKO/CD46). Percentages of CD42a‐positive platelet aggregates with WBC‐subtypes were determined by flow cytometry, and absolute numbers (per mm3) were calculated. Platelet aggregates in the liver xenografts were identified by immunofluorescence and electron microscopy. Mean platelet volume (MPV) was determined before and after transplantation.Results:  After pig liver reperfusion, profound thrombocytopenia was associated with aggregation of platelets with WBC‐subtypes. Increasing aggregation of platelets with WBC‐subtypes was detected throughout the post‐transplant period until the recipient was euthanized. Significant negative correlation was found between platelet counts in the blood and aggregation of platelets with monocytes (P < 0.01) and neutrophils (P < 0.01), but not with lymphocytes. MPV remained within the normal range. Two hours after reperfusion, platelet and fibrin deposition were already detected in the liver xenografts by immunofluorescence and by electron microscopy.Conclusions:  Following liver xenotransplantation, the early disappearance of platelets from the circulation was at least in part due to their aggregation with circulating WBC, which may augment their deposition in the liver xenograft and native lungs. Prevention of platelet aggregation with monocytes and neutrophils is likely beneficial in reducing their subsequent sequestration in the liver xenograft and native organs.
Does Weather or Site Characteristics Influence the Ability of Scavengers to Locate Food?
Authors: Ruzicka Rebekah E. , Conover Michael R. 
Published: December 2011

AbstractOlfactory predators and scavengers rely on odors to locate food, and they forage primarily at night. We hypothesized that weather (e.g. wind speed, humidity, and temperature), vegetation, and landscape features affect the dissipation of odors in the atmosphere and, thus, impact the foraging efficiency of olfactory predators. We tested this hypothesis by assessing what conditions were correlated with the persistence of bait along the dike surrounding Willard Bay Reservoir, Utah. We distributed 124 chicken eggs and 199 dead European starlings (Sturnus vulgaris) as bait over 21 separate occasions spanning from May 21, 2009, to August 18, 2009. We used timers to record the time of consumption and cameras to identify which species ate the bait. Sixty‐six eggs and 87 dead European starlings were consumed. The bait was consumed mostly at night (83%) and by striped skunks (Mephitis mephitis), raccoons (Procyon lotor), and red foxes (Vulpes vulpes). We used nest survival models in program MARK to determine which covariates influenced bait persistence. We tested nine variables and found that bait persistence was influenced by section of the dike, time since study initiation, temperature, humidity, and wind speed but not bait type (egg or dead European starling), terrain, or visual cover. How quickly scavengers were able to locate food, which was inversely related to rates of bait persistence, decreased with higher temperatures and wind speeds and increased with higher humidity. Our results support the hypothesis that weather and micro‐habitat characteristics impact the ability of olfactory predators and scavengers to locate food.
Infanticide and Population Growth in the Bank Vole (Myodes glareolus): The Effect of Male Turnover and Density
Authors: Opperbeck Annika , Ylönen Hannu , Klemme Ines 
Published: December 2011

AbstractOne major intrinsic factor affecting recruitment of young into a population is infanticide, the killing of conspecific young by adult males. It occurs in most mammal species, like our study species the bank vole (Myodes glareolus), and is widely accepted as an adaptive behavior, which may increase male fitness via nutritional gain, decreased competition, or an increased access to mates. A turnover of males in a population increases the risk of infanticide owing to a disruption of social structures. In a controlled field study, we tested the effects of total male turnover and density on juvenile recruitment and female space use in experimental bank vole populations. Juvenile recruitment declined significantly in low‐density populations with male turnover, while growth of high‐density populations seemed unaffected. The females’ spatial behavior seemed unaffected by both male turnover and density. Our results suggest that male infanticide may considerably affect population growth and it is more likely to do so at lower densities.
Evaluation of a peanut collection for shell‐colour traits in two diverse soil types
Authors: Hovav Ran , Badani Hana , Ginzberg Idit , Chedvat Ilan , Brand Yael , Galili Shmuel 
Published: December 2011

With 4 figures and 3 tablesAbstractIn the in‐shell peanut market, consumers favour the bright yellow shells characteristic of peanuts grown in sandy soils. Expanding cultivation of commercial varieties into areas with heavier soils has led to a less desirable brown tint, and reduced crop marketability. To overcome this, we evaluated a collection of 97 genotypes for shell colour when grown in sandy or semi‐red soils to identify genotypes that have bright shells when grown in heavier soils. Residual maximum likelihood analyses of spectrophotometer‐based parameters indicated significant genotype × soil interaction effects for all of the examined colour variables: brightness, red and yellow. In the heavier soil, there was also a significant correlation between maturity and the red variable. The pods of several early‐maturing genotypes, mainly from the fastigiata group, had similar or better scores in the heavier soil than in the sandy soil. We did not observe any significant correlations between colour variables and other important pod traits, aside from maturity and shell thickness, highlighting the potential for introducing desirable pod colour into local cultivars to be grown in heavy soils.
Molecular cytogenetic identification of a wheat‐Aegilops geniculata Roth spontaneous chromosome substitution and its effects on the growth and physiological responses of seedlings to osmotic stress
Authors: Landjeva Svetlana , Kocheva Konstantina , Karceva Tania , Sepsi Adél , Molnár István , Schneider Annamária , Ganeva Ganka , Georgiev Georgi , Molnár‐Láng Márta 
Published: December 2011

With 6 figures and 1 tableAbstractThe karyotypic constitution of a wheat‐Aegilops geniculata 2Mg(2A) disomic substitution line, isolated from backcross progenies of a wheat‐Ae. geniculata amphiploid, was determined using multicolour fluorescence in situ hybridization and genomic in situ hybridization. The ability of the 2Mg chromosome to compensate for wheat chromosome 2A was studied in relation to phenotypic traits and the growth and physiological responses of seedlings to polyethylene glycol (PEG)‐induced osmotic stress. Plants of the substitution line had altered spike and seed morphologies, increased tillering, moderately reduced productivity and maintained better seedling growth in stress conditions. PEG treatment caused severe stress, resulting in considerable water loss from the leaves. Under this stress, the substitution line retained better leaf water status and suffered less oxidative damage than the wheat parent, as indicated by higher relative water content and lower malondialdehyde accumulation. These changes were consistent with more sustained membrane stability in the substitution line, evidenced by the lower value of the membrane injury index and the less‐prominent increase in ion efflux from the apoplast.
Characteristics of Bovine Oocytes with Different Meiotic Competence in Terms of Their Mitochondrial Status and Expression of Nuclear‐Encoded Factors
Authors: Machatkova M , Jeseta M , Hulinska P , Knitlova D , Nemcova L , Kanka J 
Published: December 2011

ContentThe present study was designed to characterize bovine oocytes with different meiotic competence and atresia levels in terms of their mitochondrial status. Oocyte subpopulations were recovered either from medium (MF) or small (SF) follicles and categorized as healthy, light‐atretic and mid‐atretic according to oocyte morphology. Mitochondrial activity, morphology and distribution, adenosine triphosphate (ATP) content and expression of mitochondrial transcription factor A (TFAM) and nuclear respiratory factor 1 (NRF1) were assessed before (GV) and after (MII) maturation. The data were related to follicular size regardless of or with regard to oocyte atresia. Regardless of atresia, the MF subpopulation showed a significantly higher mitochondrial activity and frequency of oocytes with granulated mitochondria at GV and clustered mitochondria at MII than the SF subpopulation. With regard to atresia, mitochondrial activity decreased from healthy to mid‐atretic oocytes in both MF and SF subpopulations at GV, but in the SF subpopulation at MII, the mitochondrial activity and frequency of oocytes with clustered mitochondria were significantly higher in light‐atretic than in healthy oocytes. The light‐atretic oocytes also produced more ATP than healthy ones in both SF and MF subpopulations. However, a significantly higher relative abundance of mRNA TFAM was found in SF than MF subpopulations at GV, and this difference remained in mid‐atretic oocytes at MII. It can be concluded that meiotic competence and atresia level influence mitochondrial status of immature bovine oocytes. After maturation, healthy oocytes from medium follicles and light‐atretic oocytes from small follicles were more developed in terms of mitochondrial status than the other oocytes.
Low expression of DAB2IP contributes to malignant development and poor prognosis in hepatocellular carcinoma
Authors: Zhang Xiaojing , Li Ning , Li Xianzheng , Zhao Wei , Qiao Yudan , Liang Li , Ding Yanqing 
Published: December 2011

AbstractBackground and Aim:  DOC‐2/DAB2 interactive protein gene (DAB2IP) is a novel member of the Ras GTPase‐activating protein family and plays a tumor suppressive role in cancer progression, but its function in hepatocellular carcinoma (HCC) remains unclear. This aims of this study were to analyze the clinicopathological features of DAB2IP expression in HCC, and to determine the effect of DAB2IP on HCC cell behaviors in vitro.Methods:  The expression of DAB2IP was detected in hepatocyte cell line and HCC cell lines by real‐time reverse transcription‐polymerase chain reaction and western blot. DAB2IP expression was then examined in 120 cases of clinical paraffin‐embedded HCC tissue by immunohistochemistry (IHC). 3‐(4,5)‐dimethylthiahiazo (‐z‐y1)‐3,5‐di‐ phenytetrazoliumromide (MTT) method and in vitro invasive assay were finally performed to evaluate the effect of DAB2IP depletion on cell proliferation or invasion of HCC cells.Results:  DAB2IP expression was lower in HCC cell lines or tissues than in hepatocyte cell lines, adjacent cirrhotic livers or normal livers (P < 0.05). Its expression was positively correlated with tumor size (P = 0.01). Patients with lower DAB2IP expression had shorter overall survival time (P = 0.013). DAB2IP suppresses proliferation and invasion of HCC cells in vitro.Conclusion:  DAB2IP is a valuable marker for progression of HCC patients. Downregulation of DAB2IP is associated with poor prognosis in HCC patients. DAB2IP silence alone is sufficient to promote HCC cell proliferation and invasion in vitro.