bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thermoperiodic response and effect of photoperiod on thermoperiodic induction of diapause in Colaphellus bowringi
Authors: Wang Xiao‐Ping , Xue Fang‐Sen , Zhou Xing‐Miao , Lei Chao‐Liang 
Published: June 2007

AbstractThe effects of thermoperiods on diapause induction under continuous darkness (DD), continuous light (LL), and an L12:D12 photoperiod were investigated in the cabbage beetle, Colaphellus bowringi Baly (Coleoptera: Chrysomelidae), a short‐day species. Diapause could be induced by thermoperiod under both LL and DD; however, in the range of 24–30 °C, lower incidences of diapause were observed under LL than under DD. The critical cryophase was found to be dependent on the mean temperature of the thermoperiod applied. Although the thermoperiodic response pattern was similar under LL and DD, the incidence of diapause was higher under LL when the duration of the cryophase did not exceed 12 h. In contrast, when the duration of the cryophase was longer than 12 h, the incidence of diapause under LL was lower or equal to that under DD. When a thermoperiod of 24 °C (cryophase) and 28 °C (thermophase) was applied, the incidence of diapause was higher under LL than under DD, regardless of the duration of the cryophase. Thermoperiodic responses under a photoperiod of L12:D12 and under DD further revealed that induction of diapause was strongly influenced by the photophase temperature. Moreover, the incidence of diapause was lower when the thermophase coincided with the photophase than when the cryophase coincided with the photophase.
Bacterial challenge and eicosanoids act in plasmatocyte spreading
Authors: Kwon Hyeog Sun , Stanley David W. , Miller Jon S. 
Published: June 2007

AbstractWe report on experiments designed to more thoroughly document the roles of eicosanoids as crucial elements in cell spreading and on experiments designed to test the hypothesis that in vivo bacterial infections influence cell spreading on glass surfaces. We used hemocytes prepared from tobacco hornworms, Manduca sexta (L.) (Lepidoptera: Sphingidae) and four species of bacteria (Serratia marcescens, Escherichia coli, Bacillus subtilis, and Micrococcus luteus) in each experiment. Our protocols yielded several important points: (i) hemocytes prepared from hornworms at 15 and 60 min following infection with, separately, each of the four bacterial species were fundamentally altered in size (all less than the 15‐µm counting cut‐off) and none of the hemocytes exhibited cell‐spreading behavior; (ii) the influence of bacterial challenge on cell spreading declined with incubation time post‐challenge; (iii) conditioned medium (CM) prepared by exposing hemocytes to bacterial cells in vitro exerted a strong dose‐dependent influence on cell spreading. Specifically, plasmatocytes increased in length from about 38 µm with 2.5% CM to a maximum of about 54 µm at 100% CM; and (iv) the retarding influence of dexamethasone (an eicosanoid biosynthesis inhibitor) on cell spreading was reversed by arachidonic acid, prostaglandin H2, and CM. Taken together, these findings indicate that both bacterial infection and eicosanoids influence hemocyte‐spreading processes.
Effects of transgenic Bt cotton on insecticide use and abundance of two generalist predators
Authors: Sisterson Mark S. , Biggs Robert W. , Manhardt Nancy M. , Carrière Yves , Dennehy Timothy J. , Tabashnik Bruce E. 
Published: June 2007

AbstractConsiderable effort has been expended to determine if crops genetically engineered to produce Bacillus thuringiensis (Bt) toxins harm non‐target arthropods. However, if Bt crops kill target pests and thereby reduce insecticide use, this could benefit some non‐target arthropods. We analyzed data from 21 commercial cotton fields in Arizona to test the effects of Bt cotton on insecticide use and abundance of two non‐target arthropods, the generalist predators Chrysoperla carnea Stephens (Neuroptera: Chrysopidae) and Orius tristicolor (White) (Heteroptera: Anthocoridae). The number of insecticide sprays was more than double for non‐Bt cotton compared with Bt cotton that produced Cry1Ac. The abundance of both predators was negatively associated with the number of insecticide sprays, although significantly so for only one of two sampling periods for each species tested. With the effects of insecticides statistically removed, field type (Bt or non‐Bt cotton) did not affect the abundance of either predator. Accordingly, without adjusting for the effects of insecticide sprays, the abundance of C. carnea was higher in Bt cotton fields than in non‐Bt cotton fields, but significantly so during only one of two sampling periods. The abundance of O. tristicolor did not differ between field types, even without adjusting for effects of insecticide sprays. The results indicate that Bt crops can affect insecticide use, which in turn can affect the relative abundance of non‐target arthropods in Bt and non‐Bt fields. Thus, environmental impact assessment should incorporate analysis of the effects of transgenic crops on management practices, as well as evaluation of the direct effects of such crops.
Childrens'and Adolescents'Use of Diaries for Sickle Cell Pain
Authors: Maikler Virginia Egbert , Broome Marion E. , Bailey Patricia , Lea Gwen 
Published: June 2007

ISSUES AND PURPOSE. To evaluate the characteristics of vaso‐occlusive episodes, home management of pain and its impact on the daily activities, and a diary as a method of data collection.DESIGN AND METHODS. Forty‐six adolescents and 75 children were asked to complete daily diaries during the intervention period of a larger study.RESULTS. Mild pain was recorded 95% of the time; moderate pain, 3%; and severe pain, 1%. The pattern and location of pain varied greatly. Adolescents used more interventions than did children. When pain intensity was mild, 80% of the children/adolescents maintained school, social, and home activities, but decreased play/sport activities. When pain intensity was high, they decreased their participation in all activities.PRACTICE IMPLICATIONS. Sickle cell pain episodes are unpredictable and highly variable. Diaries can enhance children's and adolescents’documentation and communication about their pain experiences.
Influence of pod maturity and level of domestication on biochemical components in wild and cultivated pigeonpea (Cajanus cajan)
Authors: Aruna R. , Rao D. Manohar , Reddy L.J. , Ramakrishnan S. Siva , Upadhyaya H.D. 
Published: June 2007

AbstractVariations in the trypsin inhibitors and lectin content in the developing pods of thirty accessions of Cajanus scarabaeoides, a wild relative of pigeonpea, from wide geographical locations and six cultivated genotypes were estimated at juvenile, immature and mature stages of pod development. Genotypes differed at all three stages for these two biochemical components. Total protein and trypsin inhibitor contents were higher in the wild accessions than in the cultivated genotypes. Although lectin content in the juvenile stage of pod development in the wild accessions ICPW 138 and ICPW 98 was highest, it was absent in the mature pods in both the cultivated and the wild genotypes. Very high broad‐sense heritability estimates indicated the possibility of involvement of few genes in the inheritance of these biochemical components, which could be easily introgressed into the elite agronomic background.
Uganda's Civil War and the Politics of ICC Intervention
Authors: Branch Adam 
Published: June 2007

The International Criminal Court‘s intervention into the ongoing civil war in northern Uganda evoked a chorus of confident predictions as to its capacity to bring peace and justice to the war-torn region. This optimism is unwarranted, however. The article analyzes the consequences for peace and justice of the ICC's intervention, dividing them into two categories: those resulting from the political instrumentalization of the ICC by the Ugandan government, and those resulting from the discourse and practice of the ICC as an institution of global law enforcement.As to the first, the article argues that the Ugandan government referred the conflict to the ICC in order to obtain international support for its militarization and to entrench, not resolve, the war; the ICC, in accepting the referral and prosecuting only the Lord‘s Resistance Army, has in effect chosen to pursue a politically pragmatic case even though doing so contravenes the interests of peace, justice, and the rule of law. As to the second, the article reveals the harmful effects that ICC intervention can have on the capacity for autonomous political organization and action among civilian victims of violence, specifically how it leads to depoliticization by promoting a political dependency mediated by international law. The article draws from this analysis disturbing implications about ICC interventions generally, and concludes by asking whether ICC practice may be reformed so as to avoid these negative consequences.
Acute resistance exercise increases skeletal muscle angiogenic growth factor expression
Authors: Gavin T. P. , Drew J. L. , Kubik C. J. , Pofahl W. E. , Hickner R. C. 
Published: June 2007

AbstractAims:  Both aerobic and resistance exercise training promote skeletal muscle angiogenesis. Acute aerobic exercise increases several pro‐angiogenic pathways, the best characterized being increases in vascular endothelial growth factor (VEGF). We hypothesized that acute resistance exercise also increases skeletal muscle angiogenic growth factor [VEGF and angiopoietin (Ang)] expression.Methods:  Seven young, sedentary individuals had vastus lateralis muscle biopsies and blood drawn prior to and at 0, 2 and 4 h post‐resistance exercise for the measurement of VEGF; VEGF receptor [KDR, Flt‐1 and neuropilin 1 (Nrp1)]; Ang1 and Ang2; and the angiopoietin receptor – Tie2 expression. Resistance exercise consisted of progressive knee extensor (KE) exercise to determine one repetition maximum (1‐RM) followed by three sets of 10 repetitions (3 × 10) of KE exercise at 60–80% of 1‐RM.Results:  Resistance exercise significantly increased skeletal muscle VEGF mRNA and protein and plasma VEGF protein at 2 and 4 h. Resistance exercise increased KDR mRNA and Tie2 mRNA at 4 h and Nrp1 mRNA at 2 and 4 h. Skeletal muscle Flt‐1, Ang1, Ang2 and Ang2/Ang1 ratio mRNA were not altered by resistance exercise.Conclusions:  These findings suggest that acute resistance exercise increases skeletal muscle VEGF, VEGF receptor and angiopoietin receptor expression. The increases in muscle angiogenic growth factor expression in response to acute resistance exercise are similar in timing and magnitude with responses to acute aerobic exercise and are consistent with resistance exercise promoting muscle angiogenesis.
Intracellular signalling pathways in the vasoconstrictor response of mouse afferent arterioles to adenosine
Authors: Hansen P. B. , Friis U. G. , Uhrenholt T. R. , Briggs J. , Schnermann J. 
Published: June 2007

AbstractAims:  Adenosine causes vasoconstriction of afferent arterioles of the mouse kidney through activation of adenosine A1 receptors and Gi‐mediated stimulation of phospholipase C. In the present study, we further explored the signalling pathways by which adenosine causes arteriolar vasoconstriction.Methods and results:  Adenosine (10−7 m) significantly increased the intracellular calcium concentration in mouse isolated afferent arterioles measured by fura‐2 fluorescence. Pre‐treatment with thapsigargin (2 μm) blocked the vasoconstrictor action of adenosine (10−7 m) indicating that release of calcium from the sarcoplasmic reticulum (SR), stimulated presumably by IP3, is involved in the adenosine contraction mechanism of the afferent arteriole. In agreement with this notion is the observation that 2 aminoethoxydiphenyl borate (100 μm) blocked the adenosine‐induced constriction whereas the protein kinase C inhibitor calphostin C had no effect. The calcium‐activated chloride channel inhibitor IAA‐94 (30 μm) inhibited the adenosine‐mediated constriction. Patch clamp experiments showed that adenosine treatment induced a depolarizing current in preglomerular smooth muscle cells which was abolished by IAA‐94. Furthermore, the vasoconstriction caused by adenosine was significantly inhibited by 5 μm nifedipine (control 8.3 ± 0.2 μm, ado 3.6 ± 0.6 μm, ado + nifedipine 6.8 ± 0.2 μm) suggesting involvement of voltage‐dependent calcium channels.Conclusion:  We conclude that adenosine mediates vasoconstriction of afferent arterioles through an increase in intracellular calcium concentration resulting from release of calcium from the SR followed by activation of Ca2+‐activated chloride channels leading to depolarization and influx of calcium through voltage‐dependent calcium channels.
New Guinea Pig Model of Cryptococcal Meningitis
Authors: Kirkpatrick William R. , Najvar Laura K. , Bocanegra Rosie , Patterson Thomas F. , Graybill John R. 
Published: June 2007

ABSTRACT

We developed a guinea pig model of cryptococcal meningitis to evaluate antifungal agents. Immunosuppressed animals challenged intracranially with
Cryptococcus neoformans
responded to fluconazole and voriconazole. Disease was monitored by serial cerebrospinal fluid (CSF) cultures and quantitative organ cultures. Our model produces disseminating central nervous system disease and responds to antifungal therapy.
Large-Scale Surveillance of
Plasmodium falciparum crt
(
K76T
) in Northern Ghana
Authors: Ehrhardt Stephan , Eggelte Teunis A. , Kaiser Sarah , Adjei Lydia , Burchard Gerd D. , Anemana Sylvester D. , Bienzle Ulrich , Mockenhaupt Frank P. 
Published: June 2007

ABSTRACT

Surveillance of
Plasmodium falciparum crt
(
K76T
) [Pf
crt
(
K76T
)], a resistance marker of chloroquine and, limitedly, amodiaquine, in >4,000 children in northern Ghana revealed a prevalence of 79%. Pf
crt
(
K76T
) was heterogeneously distributed and associated with chloroquine use, low parasitemia, and the dry season. Widespread chloroquine resistance challenges the regional life span of amodiaquine as a partner drug in artemisinin combination therapy.
Peroxide Bond-Dependent Antiplasmodial Specificity of Artemisinin and OZ277 (RBx11160)
Authors: Kaiser Marcel , Wittlin Sergio , Nehrbass-Stuedli Angela , Dong Yuxiang , Wang Xiaofang , Hemphill Andrew , Matile Hugues , Brun Reto , Vennerstrom Jonathan L. 
Published: June 2007

ABSTRACTUsing nonperoxidic analogs of artemisinin and OZ277 (RBx11160), the strong in vitro antiplasmodial activities of the latter two compounds were shown to be peroxide bond dependent. In contrast, the weak activities of artemisinin and OZ277 against six other protozoan parasites were peroxide bond independent. These data support the iron-dependent artemisinin alkylation hypothesis.
Emergence of KPC-2 and KPC-3 in Carbapenem-Resistant
Klebsiella pneumoniae
Strains in an Israeli Hospital
Authors: Leavitt Azita , Navon-Venezia Shiri , Chmelnitsky Inna , Schwaber Mitchell J. , Carmeli Yehuda 
Published: June 2007

ABSTRACT

Carbapenem resistance due to KPC has rarely been observed outside the United States. We noticed a sharp increase in carbapenem-resistant
Klebsiella pneumoniae
strains possessing KPC in Tel Aviv Medical Center from 2004 to 2006. Sixty percent of the isolates belonged to a single clone susceptible only to gentamicin and colistin and carried the
bla
KPC-3
gene, while almost all other clones carried the
bla
KPC-2
gene. This rapid dissemination of KPC outside the United States is worrisome.
Effect of Fluoroquinolone Treatment on Growth of and Toxin Production by Epidemic and Nonepidemic
Clostridium difficile
Strains in the Cecal Contents of Mice
Authors: Adams Daniel A. , Riggs Michelle M. , Donskey Curtis J. 
Published: June 2007

ABSTRACT

Several recent outbreaks of
Clostridium difficile
-associated disease (CDAD) have been attributed to the emergence of an epidemic strain with increased resistance to fluoroquinolone antibiotics. Some clinical studies have suggested that fluoroquinolones with enhanced antianaerobic activity (i.e., gatifloxacin and moxifloxacin) may have a greater propensity to induce CDAD than ciprofloxacin and levofloxacin do. We examined the effects of subcutaneous fluoroquinolone treatment on in vitro growth of and toxin production by epidemic and nonepidemic
C. difficile
isolates in cecal contents of mice and evaluated the potential for these agents to inhibit fluoroquinolone-susceptible isolates during treatment. When
C. difficile
isolates were inoculated into cecal contents collected 2 days after the final antibiotic dose, gatifloxacin and moxifloxacin promoted significantly more growth and toxin production than ciprofloxacin and levofloxacin did. During treatment, gatifloxacin and moxifloxacin inhibited growth of fluoroquinolone-susceptible but not fluoroquinolone-resistant isolates. Ciprofloxacin and levofloxacin promoted growth of
C. difficile
when administered at higher doses (i.e., 20 times the human dose in mg/kg of body weight), and levofloxacin inhibited growth of fluoroquinolone-susceptible, but not fluoroquinolone-resistant,
C. difficile
isolates when administered in combination with ceftriaxone. Thus, fluoroquinolones with enhanced antianaerobic activity (i.e., gatifloxacin and moxifloxacin) promoted
C. difficile
growth to a greater extent than did ciprofloxacin and levofloxacin in this model. However, our findings suggest that fluoroquinolones may exert selective pressure favoring the emergence of epidemic fluoroquinolone-resistant
C. difficile
strains by inhibiting fluoroquinolone-susceptible but not fluoroquinolone-resistant isolates during treatment and that agents such as levofloxacin or ciprofloxacin can exert such selective pressure when administered in combination with antibiotics that disrupt the anaerobic microflora.
Helicobacter pyloriInfection Induces Oxidative Stress and Programmed Cell Death in Human Gastric Epithelial Cells
Authors: Ding Song-Ze , Minohara Yutaka , Fan Xue Jun , Wang Jide , Reyes Victor E. , Patel Janak , Dirden-Kramer Bernadette , Boldogh Istvan , Ernst Peter B. , Crowe Sheila E. 
Published: June 2007

ABSTRACTHelicobacter pyloriinfection is associated with altered gastric epithelial cell turnover. To evaluate the role of oxidative stress in cell death, gastric epithelial cells were exposed to various strains ofH. pylori, inflammatory cytokines, and hydrogen peroxide in the absence or presence of antioxidant agents. Increased intracellular reactive oxygen species (ROS) were detected using a redox-sensitive fluorescent dye, a cytochromecreduction assay, and measurements of glutathione. Apoptosis was evaluated by detecting DNA fragmentation and caspase activation. Infection withH. pylorior exposure of epithelial cells to hydrogen peroxide resulted in apoptosis and a dose-dependent increase in ROS generation that was enhanced by pretreatment with inflammatory cytokines. Basal levels of ROS were greater in epithelial cells isolated from gastric mucosal biopsy specimens fromH. pylori-infected subjects than in cells from uninfected individuals.H. pyloristrains bearing thecagpathogenicity island (PAI) induced higher levels of intracellular oxygen metabolites than isogeniccagPAI-deficient mutants.H. pyloriinfection and hydrogen peroxide exposure resulted in similar patterns of caspase 3 and 8 activation. Antioxidants inhibited both ROS generation and DNA fragmentation byH. pylori. These results indicate that bacterial factors and the host inflammatory response confer oxidative stress to the gastric epithelium duringH. pyloriinfection that may lead to apoptosis.
Relative Importance of T-Cell Subsets in Monocytotropic Ehrlichiosis: a Novel Effector Mechanism Involved inEhrlichia-Induced Immunopathology in Murine Ehrlichiosis
Authors: Ismail Nahed , Crossley Emily C. , Stevenson Heather L. , Walker David H. 
Published: June 2007

ABSTRACTInfection with gram-negative monocytotropicEhrlichiastrains results in a fatal toxic shock-like syndrome characterized by a decreased number ofEhrlichia-specific CD4+Th1 cells, the expansion of tumor necrosis factor alpha (TNF-α)-producing CD8+T cells, and the systemic overproduction of interleukin-10 (IL-10) and TNF-α. Here, we investigated the role of CD4+and CD8+T cells in immunity toEhrlichiaand the pathogenesis of fatal ehrlichiosis caused by infection with low- and high-dose (103and 105bacterial genomes/mouse, respectively) ehrlichial inocula. The CD4+T-cell-deficient mice showed exacerbated susceptibility to a lethal high- or low-dose infection and harbored higher bacterial numbers than did wild-type (WT) mice. Interestingly, the CD8+T-cell-deficient mice were resistant to a low dose but succumbed to a high dose ofEhrlichia. The absence of CD8+T cells abrogated TNF-α and IL-10 production, reduced tissue injury and bacterial burden, restored splenic CD4+T-cell numbers, and increased the frequency ofEhrlichia-specific CD4+Th1 cells in comparison to infected WT mice. Although fatal disease is perforin independent, our data suggested that perforin played a critical role in controlling bacterial burden and mediating liver injury. Similar to WT mice, mortality of infected perforin-deficient mice was associated with CD4+T-cell apoptosis and a high serum concentration of IL-10. Depletion of IL-10 restored the number of CD4+and CD8+T cells in infected WT mice. Our data demonstrate a novel mechanism of immunopathology in which CD8+T cells mediateEhrlichia-induced toxic shock, which is associated with IL-10 overproduction and CD4+T-cell apoptosis.
Pertussis Toxin Utilizes Proximal Components of the T-Cell Receptor Complex To Initiate Signal Transduction Events in T Cells
Authors: Schneider Olivia D. , Weiss Alison A. , Miller William E. 
Published: June 2007

ABSTRACTPertussis toxin (PTx) is an AB5toxin produced by the human pathogenBordetella pertussis. Previous work demonstrates that the five binding (B) subunits of PTx can have profound effects on T lymphocytes independent of the enzymatic activity of the A subunit. Stimulation of T cells with holotoxin (PTx) or the B subunit alone (PTxB) rapidly induces signaling events resulting in inositol phosphate accumulation, Ca2+mobilization, interleukin-2 (IL-2) production, and mitogenic cell growth. Although previous reports suggest the presence of PTx signaling receptors expressed on T cells, to date, the receptor(s) and membrane proximal signaling events utilized by PTx remain unknown. Here we genetically and biochemically define the membrane proximal components utilized by PTx to initiate signal transduction in T cells. Using mutants of the Jurkat T-cell line deficient for key components of the T-cell receptor (TCR) pathway, we have compared stimulation with PTx to that of anti-CD3 monoclonal antibody (MAb), which directly interacts with and activates the TCR complex. Our genetic data in combination with biochemical analysis show that PTx (via the B subunit) activates TCR signaling similar to that of anti-CD3 MAb, including activation of key signaling intermediates such as Lck, ZAP-70, and phospholipase C-γ1. Moreover, the data indicate that costimulatory activity, as provided by CD28 ligation, is required for PTx to fully stimulate downstream indicators of T-cell activation such as IL-2 gene expression. By illuminating the signaling pathways that PTx activates in T cells, we provide a mechanistic understanding for how these signals deregulate immune system functions duringB. pertussisinfection.