Some biological parameters of Sympiesis striatipes (Hym.: Eulophidae), an ectoparasitoid of the citrus leafminer Phyllocnistis citrella (Lep.: Gracillariidae)

The biological parameters of Sympiesis striatipes Ashmead, one of the most abundant hymenopterous ectoparasitoid of Phyllocnistis citrella Stainton in Ehime province of Japan, were studied under laboratory and field conditions. The mean immature developmental time and adult longevity at different temperatures (22 to 31°C), 50-70% RH and 12L: 12D photoperiod decreased as the temperature increased, and females survived longer than males. Offspring sex ratio from females provided with males was 84.7% males and 15.3% females. Presumably mated females began oviposition 2-3 days after emergence and continued up to 39 days. Each female laid a mean of 123.4 ± 13.97, and longevity reached 33.8 ± 1.5 days at 27 ± 1°C, 50-70% RH and 12L: 12D photoperiod. The intrinsic rate of natural increase (rm) was 0.312. Host feeding or stinging without oviposition killed 44.7 ± 4.2 host larvae per female parasitoid. Seventy five point eight percent of eggs were laid on third instar larva of host and the remainder on the prepupa. Under field conditions, superparasitism on the third instar larvae was 9.2% (n = 200) and up to 7 eggs per host were recorded. Under superparasitism lethal competition (n = 40), one adult parasitoid per host emerged from 87.5% of the samples and two adult parasitoids per host emerged from the rest. Superparasitism on prepupa was rare. The sex ratio (M: F) of the parasitoid oviposited on the third instar larvae of host and pupae was 2.2: 1.0, and 1.3: 3.0, respectively

Effect of interleukins response to ECM-induced acquisition of drug resistance in MCF-7 cells

Aim: To examine the effect of various components of extracellular matrix (ECM) on acquisition of drug resistance to taxol and camptothecin by breast carcinoma cell line MCF-7. Methods: Cancer cells were cultured on bovine serum albumin (BSA), vitronectin (VN), fibronectin (FN), collagen type I (COL-I), or Matrigel-coated plates with or without taxol (paclitaxel) or camptothecin treatment. The effect of anticancer drugs on cell growth was accessed by XTT assay, and the alterations of cellular morphology were examined by phase contrast microscopy. Immunofluorescence study was performed using monoclonal anti-b-tubulin antibody. Results: All cell lines showed a significant decrease in cell survival when treated with anticancer drugs without components of ECM, whereas survival rates of Caco-2, MCF-7 and NCI-H292 were significantly increased when cells were cultured on COL-I- and Matrigel-coated dishes after treatment with paclitaxel or camptothecin. MCF-7 cells showed and maintained a colony formation when cultured on the COL-I- and Matrigel-coated dish. Moreover, cytotoxicity (IC50) was decreased by taxol (paclitaxel) or camptothecin treatment during colony formation in MCF-7 cells, suggesting that morphological changes could increase survival of cells treated with anticancer drugs. Thick circumferential bundles of microtubules around the periphery of the cells and chromatin condensation was not observed for MCF-7 cells on COL-I- and Matrigel-coated dishes treated with paclitaxel. To confirm this, spheroid cells were prepared, and we found that cytotoxicity was decreased for these cells, and significantly increased when cells were co-cultured on Matrigel- or COL-I-coated upper wells. The effect of anticancer drugs on cell survival was efficiently inhibited by interleukin-6 (IL-6) and interleukin-8 (IL-8). Conclusions: Present results suggested that not only integrin-ECM interactions but also other factors such as IL-6 and IL-8 secreted by cancer cells, cultured on COL-I and Matrigel dishes, are involved in the acquisition of drug resistance by MCF-7.Цель: изучить влияние различных компонентов внеклеточного матрикса (ECM) на приобретение химиорезистентности к таксолу и камптотецину клетками линии карциномы молочной железы MCF-7. Методы: клетки культивировали на платах, покрытых бычьим сывороточным альбумином (BSA), витронектином (VN), фибронектином (FN), коллагеном I типа (COL-I) или матригелем, без и с добавлением таксола (паклитаксел) или камптотецина. Влияние противоопухолевых препаратов на рост клеток изучали с помощью XTT-теста, изменения клеточной морфологии отмечали в фазовом контрастном микроскопе. Иммунофлуоресцентным методом определяли экспрессию β-тубулина. Результаты: для всех клеточных линий показано существенное снижение выживаемости после культивирования с противоопухолевыми препаратами без компонентов ECM, в то время как уровень выживаемости клеток Caco-2, MCF-7 и NCI-H292 значительно возрос при культивировании с таксолом или камптотецином в чашках, покрытых COL-I и матригелем. Для клеток MCF-7 показано формирование и сохранение колоний при культивировании в чашках с COL-I и матригелем. Более того, цитотоксичность (IC50) таксола и во время колониеобразования клеток MCF-7 была снижена, что позволяет предположить, что морфологические изменения могут влиять на выживаемость клеток при культивировании с химиопрепаратом. Для клеток MCF-7, выращиваемых на чашках с COL-I и матригелем, не отмечали образования плотных периферических узлов микротрубочек и конденсации хроматина. Для подтверждения данного наблюдения проведены опыты с клетками, растущими в виде сфероидов. Показано, что цитотоксичность химиопрепаратов по отношению к этим клеткам снижалась и значительно повышалась при ко-культивировании с матригелем или COL-I в верхних камерах. Снижение выживаемости клеток под действием химиопрепаратов эффективно ингибировалось интерлейкином-6 (IL-6) и интерлейкином-8 (IL-8). Выводы: настоящие исследования показали, что не только интегрин-ECM-взаимодействия, но также и другие факторы, такие как IL-6 и IL-8, секретируемые опухолевыми клетками на чашках с COL-I и матригелем, участвуют в приобретении химиорезистентности опухолевыми клетками MCF-7

A stochastic model of Echinococcus multilocularis transmission in Hokkaido, Japan, focusing on the infection process

Echinococcus multilocularis causes human alveolar echinococcus. In Japan, high prevalence of E. multilocularis among the fox population has been reported throughout Hokkaido. Accordingly, control measures, such as fox hunting and the distribution of bait containing Praziquantel, have been conducted. This study developed a transmission model for individuals in the fox population and included a stochastic infection process to assess the prevalence of E. multilocularis. To make our model realistic, we used the worm burden for each individual in the fox population. We assumed that the worm burden depends on the number of protoscoleces in a predated vole and the number of infection experiences. We carried out stochastic simulations with 1,000 trials for the situations of Koshimizu and Sapporo, Hokkaido, Japan. The distribution of the worm burden among foxes obtained using the model agreed with dissection data. The simulation indicates that a careful choice of season is necessary for an effective distribution of Praziquantel-containing bait. A stochastic model for E. multilocularis, which can assess the range of the prevalence in the fox population, would be helpful in analyzing their complex life-cycle and also in designing control strategies.</p

Interleukin-6 gene (IL-6): a possible role in brain morphology in the healthy adult brain

Background: Cytokines such as interleukin 6 (IL-6) have been implicated in dual functions in neuropsychiatric disorders. Little is known about the genetic predisposition to neurodegenerative and neuroproliferative properties of cytokine genes. In this study the potential dual role of several IL-6 polymorphisms in brain morphology is investigated. Methodology: In a large sample of healthy individuals (N = 303), associations between genetic variants of IL-6 (rs1800795; rs1800796, rs2069833, rs2069840) and brain volume (gray matter volume) were analyzed using voxel-based morphometry (VBM). Selection of single nucleotide polymorphisms (SNPs) followed a tagging SNP approach (e.g., Stampa algorigthm), yielding a capture 97.08% of the variation in the IL-6 gene using four tagging SNPs. Principal findings/results: In a whole-brain analysis, the polymorphism rs1800795 (−174 C/G) showed a strong main effect of genotype (43 CC vs. 150 CG vs. 100 GG; x = 24, y = −10, z = −15; F(2,286) = 8.54, puncorrected = 0.0002; pAlphaSim-corrected = 0.002; cluster size k = 577) within the right hippocampus head. Homozygous carriers of the G-allele had significantly larger hippocampus gray matter volumes compared to heterozygous subjects. None of the other investigated SNPs showed a significant association with grey matter volume in whole-brain analyses. Conclusions/significance: These findings suggest a possible neuroprotective role of the G-allele of the SNP rs1800795 on hippocampal volumes. Studies on the role of this SNP in psychiatric populations and especially in those with an affected hippocampus (e.g., by maltreatment, stress) are warranted.Bernhard T Baune, Carsten Konrad, Dominik Grotegerd, Thomas Suslow, Eva Birosova, Patricia Ohrmann, Jochen Bauer, Volker Arolt, Walter Heindel, Katharina Domschke, Sonja Schöning, Astrid V Rauch, Christina Uhlmann, Harald Kugel and Udo Dannlowsk

Expression of osterix Is Regulated by FGF and Wnt/β-Catenin Signalling during Osteoblast Differentiation

Osteoblast differentiation from mesenchymal cells is regulated by multiple signalling pathways. Here we have analysed the roles of Fibroblast Growth Factor (FGF) and canonical Wingless-type MMTV integration site (Wnt/β-Catenin) signalling pathways on zebrafish osteogenesis. We have used transgenic and chemical interference approaches to manipulate these pathways and have found that both pathways are required for osteoblast differentiation in vivo. Our analysis of bone markers suggests that these pathways act at the same stage of differentiation to initiate expression of the osteoblast master regulatory gene osterix (osx). We use two independent approaches that suggest that osx is a direct target of these pathways. Firstly, we manipulate signalling and show that osx gene expression responds with similar kinetics to that of known transcriptional targets of the FGF and Wnt pathways. Secondly, we have performed ChIP with transcription factors for both pathways and our data suggest that a genomic region in the first intron of osx mediates transcriptional activation. Based upon these data, we propose that FGF and Wnt/β-Catenin pathways act in part by directing transcription of osx to promote osteoblast differentiation at sites of bone formation

The Herpesvirus Associated Ubiquitin Specific Protease, USP7, Is a Negative Regulator of PML Proteins and PML Nuclear Bodies

The PML tumor suppressor is the founding component of the multiprotein nuclear structures known as PML nuclear bodies (PML-NBs), which control several cellular functions including apoptosis and antiviral effects. The ubiquitin specific protease USP7 (also called HAUSP) is known to associate with PML-NBs and to be a tight binding partner of two herpesvirus proteins that disrupt PML NBs. Here we investigated whether USP7 itself regulates PML-NBs. Silencing of USP7 was found to increase the number of PML-NBs, to increase the levels of PML protein and to inhibit PML polyubiquitylation in nasopharyngeal carcinoma cells. This effect of USP7 was independent of p53 as PML loss was observed in p53-null cells. PML-NBs disruption was induced by USP7 overexpression independently of its catalytic activity and was induced by either of the protein interaction domains of USP7, each of which localized to PML-NBs. USP7 also disrupted NBs formed from some single PML isoforms, most notably isoforms I and IV. CK2α and RNF4, which are known regulators of PML, were dispensable for USP7-associated PML-NB disruption. The results are consistent with a novel model of PML regulation where a deubiquitylase disrupts PML-NBs through recruitment of another cellular protein(s) to PML NBs, independently of its catalytic activity

Fibroblast growth factor signalling controls nervous system patterning and pigment cell formation in Ciona intestinalis

During the development of the central nervous system (CNS), combinations of transcription factors and signalling molecules orchestrate patterning, specification and differentiation of neural cell types. In vertebrates, three types of melanin-containing pigment cells, exert a variety of functional roles including visual perception. Here we analysed the mechanisms underlying pigment cell specification within the CNS of a simple chordate, the ascidian Ciona intestinalis. Ciona tadpole larvae exhibit a basic chordate body plan characterized by a small number of neural cells. We employed lineage-specific transcription profiling to characterize the expression of genes downstream of fibroblast growth factor signalling, which govern pigment cell formation. We demonstrate that FGF signalling sequentially imposes a pigment cell identity at the expense of anterior neural fates. We identify FGF-dependent and pigment cell-specific factors, including the small GTPase, Rab32/38 and demonstrated its requirement for the pigmentation of larval sensory organs