[Pachymic acid protects against Crohn's disease-like intestinal barrier injury and colitis in miceby suppressingintestinal epithelial cell apoptosis via inhibiting PI3K/AKT signaling]

OBJECTIVE

To investigate the effect of pachymic acid (PA) against TNBS-induced Crohn's disease (CD)-like colitis in mice and explore the possible mechanism.

METHODS

Twenty-four C57BL/6J mice were randomized equally into control group, TNBS-induced colitis model group and PA treatment group. PA treatment was administered via intraperitoneal injection at the daily dose of 5 mg/kg for 7 days, and the mice in the control and model groups were treated with saline. After the treatments, the mice were euthanized for examination of the disease activity index (DAI) of colitis, body weight changes, colon length, intestinal inflammation, intestinal barrier function and apoptosis of intestinal epithelial cells, and the expressions of TNF-α, IL-6 and IL-1β in the colonic mucosa were detected using ELISA. The possible treatment targets of PA in CD were predicted by network pharmacology. String platform and Cytoscape 3.7.2 software were used to construct the protein-protein interaction (PPI) network. David database was used to analyze the GO function and KEGG pathway; The phosphorylation of PI3K/AKT in the colonic mucosal was detected with Western blotting.

RESULTS

PA significantly alleviated colitis in TNBS-treated mice as shown by improvements in the DAI, body weight loss, colon length, and histological inflammation score and lowered levels of TNF-α, IL-6 and IL-1β. PA treatment also significantly improved FITC-dextran permeability, serum I-FABP level and colonic transepithelial electrical resistance, and inhibited apoptosis of the intestinal epithelial cells in TNBS-treated mice. A total of 248 intersection targets were identified between PA and CD, and the core targets included EGFR, HRAS, SRC, MMP9, STAT3, AKT1, CASP3, ALB, HSP90AA1 and HIF1A. GO and KEGG analysis showed that PA negatively regulated apoptosis in close relation with PI3K/AKT signaling. Molecular docking showed that PA had a strong binding ability with AKT1, ALB, EGFR, HSP90AA1, SRC and STAT3. In TNBS-treated mice, PA significantly decreased p-PI3K and p-AKT expressions in the colonic mucosa.

CONCLUSION

PA ameliorates TNBS-induced intestinal barrier injury in mice by antagonizing apoptosis of intestinal epithelial cells possibly by inhibiting PI3K/AKT signaling.

Biochemical toxicity and transcriptome aberration induced by dinotefuran in Bombyx mori

Dinotefuran is a third-generation neonicotinoid pesticide and is increasingly used in agricultural production, which has adverse effects on nontarget organisms. However, the research on the impact of dinotefuran on nontarget organisms is still limited. Here the toxic effects of dinotefuran on an important economic species and a model lepidopteran insect, Bombyx mori, were investigated. Exposure to different doses of dinotefuran caused physiological disorders or death. Cytochrome P450, glutathione S-transferase, carboxylesterase, and UDP glycosyl-transferase activities were induced in the fat body at early stages after dinotefuran exposure. By contrast, only glutathione S-transferase activity was increased in the midgut. To overcome the lack of sensitivity of the biological assays at the individual organism level, RNA sequencing was performed to measure differential expressions of mRNA from silkworm larvae after dinotefuran exposure. Differential gene expression profiling revealed that various detoxification enzyme genes were significantly increased after dinotefuran exposure, which was consistent with the upregulation of the detoxifying enzyme. The global transcriptional pattern showed that the physiological responses induced by dinotefuran toxicity involved multiple cellular processes, including energy metabolism, oxidative stress, detoxification, and other fundamental physiological processes. Many metabolism processes, such as carbon metabolism, fatty acid biosynthesis, pyruvate metabolism, and the citrate cycle, were partially repressed in the midgut or fat body. Furthermore, dinotefuran significantly activated the MAPK/CREB, CncC/Keap1, PI3K/Akt, and Toll/IMD pathways. The links between physiological, biochemical toxicity and comparative transcriptomic analysis facilitated the systematic understanding of the integrated biological toxicity of dinotefuran. This study provides a holistic view of the toxicity and detoxification metabolism of dinotefuran in silkworm and other organisms.

The Neuroanatomical Basis of Two Subcomponents of Rumination: A VBM Study

Rumination is a trait that includes two subcomponents, namely brooding and reflective pondering, respectively construed as maladaptive and adaptive response styles to negative experiences. Existing evidence indicates that rumination in general is associated with structural and functional differences in the anterior cingulate cortex (ACC) and the dorsal lateral prefrontal cortex (DLPFC). However, conclusive evidence on the specific neural structural basis of each of the two subcomponents is lacking. In this voxel-based morphometry study, we investigated the independent and specific neural structural basis of brooding and reflective pondering in 30 healthy young adults, who belonged to high or low brooding or reflective pondering groups. Consistent with past research, modest but significant positive correlation was found between brooding and reflective pondering. When controlling for reflective pondering, high-brooding group showed increased gray matter volumes in the left DLPFC and ACC. Further analysis on extracted gray matter values showed that gray matter of the same DLPFC and ACC regions also showed significant negative effects of reflective pondering. Taken together, our findings indicate that the two subcomponents of rumination might share some common processes yet also have distinct neural basis. In view of the significant roles of the left DLPFC and ACC in attention and self-related emotional processing/regulation, our findings provide insight into how the potentially shared and distinct cognitive, affective and neural processes of brooding and reflective pondering can be extended to clinical populations to further elucidate the neurobehavioral relationships between rumination and prefrontal abnormality.

Growth and photoluminescence of oriented MoSe2nanosheets produced by hot filament CVD

Oriented MoSe₂nanosheets with varying layers and structures were synthesized on silicon substrates by hot filament chemical vapour deposition in a nitrogen environment using MoO₃and Se powders as precursors.

Dose Proportionality and Pharmacokinetics of Eplerenone in Healthy Chinese Subjects

BACKGROUND

Eplerenone (CAS 107724-20-9) is the first highly selective aldosterone receptor blocker and is used worldwide for treatment of hypertension and heart failure.

OBJECTIVE

The objective of this study was to investigate the eplerenone pharmacokinetics in healthy Chinese subjects and assess the dose proportionality over the therapeutic dose range.

METHODS

A single-dose, randomized, 6-sequence, 3-treatment, 3-period crossover, open label study was conducted in 12 healthy Chinese subjects, who received 3 doses of eplerenone in random order (25, 50, 100 mg). The power model was used to evaluate the dose proportionality of eplerenone. The pharmacokinetic study of multiple-dose of eplerenone was also conducted.

RESULTS

After single-dose oral administration, the mean C max value increased from 489 to 1 641 ng/mL, and the mean AUC 0-t value increased from 3 030 to 10 893 ng/mL·h with an increase in dose from 25 to 100 mg, respectively. The mean value for terminal T 1/2 was approximate 3 h with no significant differences among different dose groups. Though dose proportionality of eplerenone was inconclusive in Chinese subjects over the dose range of 25-100 mg, the maximal proportionality dose range (ρ1) was 2.06 based on power model. Steady state could achieve within at least 4 days and no accumulation was observed after multiple-dose of eplerenone.

CONCLUSION

Dose proportionality was inconclusive in over the dose range of 25-100 mg; however, linear pharmacokinetics could be considered when dose ratio is no more than 2.06.

SNPs in Entire Mitochondrial Genome Sequences (≈15.4 kb) and cox1 Sequences (≈486 bp) Resolve Body and Head Lice From Doubly Infected People From Ethiopia, China, Nepal, and Iran But Not France

Some people host lice on the clothing as well as the head. Whether body lice and head lice are distinct species or merely variants of the same species remains contentious. We sought to ascertain the extent to which lice from these different habitats might interbreed on doubly infected people by comparing their entire mitochondrial genome sequences. Toward this end, we analyzed two sets of published genetic data from double-infections of body lice and head lice: 1) entire mitochondrial coding regions (≈15.4 kb) from body lice and head lice from seven doubly infected people from Ethiopia, China, and France; and 2) part of the cox1 gene (≈486 bp) from body lice and head lice from a further nine doubly infected people from China, Nepal, and Iran. These mitochondrial data, from 65 lice, revealed extraordinary variation in the number of single nucleotide polymorphisms between the individual body lice and individual head lice of double-infections: from 1.096 kb of 15.4 kb (7.6%) to 2 bps of 15.4 kb (0.01%). We detected coinfections of lice of Clades A and C on the scalp hair of three of the eight people from Nepal: one person of the two people from Kathmandu and two of the six people from Pokhara. Lice of Clades A and B coinfected the scalp hair of one person from Atherton, Far North Queensland, Australia. These findings argue for additional large-scale studies of the body lice and head lice of double-infected people.

Second-generation sequencing of entire mitochondrial coding-regions (∼15.4 kb) holds promise for study of the phylogeny and taxonomy of human body lice and head lice

The Illumina Hiseq platform was used to sequence the entire mitochondrial coding-regions of 20 body lice, Pediculus humanus Linnaeus, and head lice, P. capitis De Geer (Phthiraptera: Pediculidae), from eight towns and cities in five countries: Ethiopia, France, China, Australia and the U.S.A. These data (∼310 kb) were used to see how much more informative entire mitochondrial coding-region sequences were than partial mitochondrial coding-region sequences, and thus to guide the design of future studies of the phylogeny, origin, evolution and taxonomy of body lice and head lice. Phylogenies were compared from entire coding-region sequences (∼15.4 kb), entire cox1 (∼1.5 kb), partial cox1 (∼700 bp) and partial cytb (∼600 bp) sequences. On the one hand, phylogenies from entire mitochondrial coding-region sequences (∼15.4 kb) were much more informative than phylogenies from entire cox1 sequences (∼1.5 kb) and partial gene sequences (∼600 to ∼700 bp). For example, 19 branches had > 95% bootstrap support in our maximum likelihood tree from the entire mitochondrial coding-regions (∼15.4 kb) whereas the tree from 700 bp cox1 had only two branches with bootstrap support > 95%. Yet, by contrast, partial cytb (∼600 bp) and partial cox1 (∼486 bp) sequences were sufficient to genotype lice to Clade A, B or C. The sequences of the mitochondrial genomes of the P. humanus, P. capitis and P. schaeffi Fahrenholz studied are in NCBI GenBank under the accession numbers KC660761-800, KC685631-6330, KC241882-97, EU219988-95, HM241895-8 and JX080388-407.

Evidence for Ixodes holocyclus (Acarina: Ixodidae) as a vector for human lyme Borreliosis infection in Australia

Ixodes holocyclus (Acarina: Ixodidae) and Ixodes cornuatus (Acarina: Ixodidae) are two tick species found in the more densely populated areas of Australia and are known to be the cause of the neurotoxic disease tick paralysis in humans and mammals. Borreliosis otherwise known as Lyme disease is an emerging infectious disease in humans in Australia. Borrelia burgdorferi sensu stricto (Spirochaetales: Spirochaetaceae) and sensu lato are closely related spirochetal species that are the causative agents of Lyme disease in humans. Clinical transmission of this tick-borne disease can be identified in several but not all cases by a characteristic rash known as erythema migrans. However, there has been no study of the tick vectors of this infection in Australia. We used morphological and molecular techniques to identify unequivocally the ticks on the patients of this study to be I. holocyclus and then show the presence of B. burgdorferi sensu stricto infection in erythema migrans biopsies. I. holocyclus has not previously been associated with erythema migrans or Lyme disease. Two patients presented to the lead author's medical practice with erythema migrans in mid and late 2012. The morphology and cytochrome oxidase 1 and ITS2 genes of the two ticks were studied. The skin at the attachment site was sampled by central biopsy for both real time and endpoint Borrelia polymerase chain reaction (PCR) analysis and subsequent sequencing. Morphologically, the two ticks were either I. holocyclus or I. cornuatus. Molecular studies and nucleotide sequencing revealed that both ticks were I. holocyclus. Real time and endpoint PCR on the central tissue biopsy samples returned positive results for B. burgdorferi DNA. Our results are evidence for transmission of B. burgdorferi sensu stricto species to humans by the tick I. holocyclus in Australia. I. holocyclus is commonly associated with human tick bites on virtually the entire eastern coastline of Australia.

Tumor-derived mural-like cells coordinate with endothelial cells: role of YKL-40 in mural cell-mediated angiogenesis

Tumor neo-vasculature is characterized by spatial coordination of endothelial cells with mural cells, which delivers oxygen and nutrients. Here, we explored a key role of the secreted glycoprotein YKL-40, a mesenchymal marker, in the interaction between endothelial cells and mesenchymal mural-like cells for tumor angiogenesis. Xenotransplantation of tumor-derived mural-like cells (GSDCs) expressing YKL-40 in mice developed extensive and stable blood vessels covered with more GSDCs than those in YKL-40 gene knockdown tumors. YKL-40 expressed by GSDCs was associated with increased interaction of neural cadherin/β-catenin/smooth muscle alpha actin; thus, mediating cell-cell adhesion and permeability. YKL-40 also induced the interaction of vascular endothelial cadherin/β-catenin/actin in endothelial cells (HMVECs). In cell co-culture systems, YKL-40 enhanced both GSDC and HMVEC contacts, restricted vascular leakage, and stabilized vascular networks. Collectively, the data inform new mechanistic insights into the cooperation of mural cells with endothelial cells induced by YKL-40 during tumor angiogenesis, and also enhance our understanding of YKL-40 in both mural and endothelial cell biology.

Shifts in reinforcement signalling while playing slot-machines as a function of prior experience and impulsivity

Electronic gaming machines (EGMs) offer significant revenue streams for mercantile gambling. However, limited clinical and experimental evidence suggests that EGMs are associated with heightened risks of clinically problematic patterns of play. Little is known about the neural structures that might mediate the transition from exploratory EGM play to the ‘addictive’ play seen in problem gamblers; neither is it known how personality traits associated with gambling activity (and gambling problems) influence reinforcement processing while playing EGMs. Using functional magnetic resonance imaging in healthy participants, we show that a single episode of slot-machine play is subsequently associated with reduced amplitudes of blood-oxygenation level-dependent signals within reinforcement-related structures, such as the ventral striatum and caudate nucleus, following winning game outcomes; but increased amplitudes of anticipatory signals within the ventral striatum and amygdala while watching the game reels spin. Trait impulsivity enhanced positive signals within the ventral striatum and amygdala following the delivery of winning outcomes but diminished positive signals following the experience of almost-winning (’near-misses’). These results indicate that a single episode of slot-machine play engages the well-characterised reinforcement-learning mechanisms mediated by ascending dopamine mesolimbic and mesostriatal pathways, to shift reward value of EGMs away from game outcomes towards anticipatory states. Impulsivity, itself linked to problem gambling and heightened vulnerability to other addictive disorders, is associated with divergent coding of winning outcomes and almost-winning experiences within the ventral striatum and amygdala, potentially enhancing the reward value of successful slot-machine game outcomes but, at the same time,modulating the aversive motivational consequences of near-miss outcomes.

Shifts in reinforcement signalling while playing slot-machines as a function of prior experience and impulsivity

Electronic gaming machines (EGMs) offer significant revenue streams for mercantile gambling. However, limited clinical and experimental evidence suggests that EGMs are associated with heightened risks of clinically problematic patterns of play. Little is known about the neural structures that might mediate the transition from exploratory EGM play to the 'addictive' play seen in problem gamblers; neither is it known how personality traits associated with gambling activity (and gambling problems) influence reinforcement processing while playing EGMs. Using functional magnetic resonance imaging in healthy participants, we show that a single episode of slot-machine play is subsequently associated with reduced amplitudes of blood-oxygenation-level-dependent signals within reinforcement-related structures, such as the ventral striatum and caudate nucleus, following winning game outcomes; but increased amplitudes of anticipatory signals within the ventral striatum and amygdala while watching the game reels spin. Trait impulsivity enhanced positive signals within the ventral striatum and amygdala following the delivery of winning outcomes but diminished positive signals following the experience of almost-winning ('near-misses'). These results indicate that a single episode of slot-machine play engages the well-characterised reinforcement-learning mechanisms mediated by ascending dopamine mesolimbic and mesostriatal pathways, to shift reward value of EGMs away from game outcomes towards anticipatory states. Impulsivity, itself linked to problem gambling and heightened vulnerability to other addictive disorders, is associated with divergent coding of winning outcomes and almost-winning experiences within the ventral striatum and amygdala, potentially enhancing the reward value of successful slot-machine game outcomes but, at the same time, modulating the aversive motivational consequences of near-miss outcomes.

Interleukin-6 receptor α is co-localised with melanin-concentrating hormone in human and mouse hypothalamus

Interleukin (IL)-6 deficient mice develop mature-onset obesity. Furthermore, i.c.v. administration of IL-6 increases energy expenditure, suggesting that IL-6 centrally regulates energy homeostasis. To investigate whether it would be possible for IL-6 to directly influence the energy homeostasis via hypothalamic regulation in humans and rodents, we mapped the distribution of the ligand binding IL-6 receptor α (IL-6Rα) in this brain region. In the human hypothalamus, IL-6Rα-immunoreactivity was detected in perikarya and first-order dendrites of neurones. The IL-6Rα-immunoreactive (-IR) neurones were observed posterior to the level of the interventricular foramen. There, IL-6Rα-IR neurones were located in the lateral hypothalamic, perifornical, dorsal and posterior hypothalamic areas, the hypothalamic dorsomedial nucleus and in the zona incerta. In the caudal part of the hypothalamus, the density of the IL-6Rα-IR neurones gradually increased. Double-labelling immunofluorescent studies demonstrated that IL-6Rα immunoreactivity was localised in the same neurones as the orexigenic neuropeptide, melanin-concentrating hormone (MCH). By contrast, IL-6Rα-immunoreactivity was not observed in the orexin B-IR neurones. To determine whether the observed expression of IL-6Rα is evolutionary conserved, we studied the co-localisation of IL-6Rα with MCH and orexin in the mouse hypothalamus, where IL-6Rα-immunoreactivity was present in numerous MCH-IR and orexin-IR neurones. Our data demonstrate that the MCH neurones of the human hypothalamus, as well as the MCH and orexin neurones of the mouse hypothalamus, contain IL-6Rα. This opens up the possibility that IL-6 influences the energy balance through the MCH neurones in humans, and both MCH and orexin neurones in mice.

Mitochondrial genomes of parasitic arthropods: implications for studies of population genetics and evolution

Over 39000 species of arthropods parasitize humans, domestic animals and wildlife. Despite their medical, veterinary and economic importance, most aspects of the population genetics and evolution of the vast majority of parasitic arthropods are poorly understood. Mitochondrial genomes are a rich source of markers for studies of population genetics and evolution. These markers include (1) nucleotide sequences of each of the 37 mitochondrial genes and non-coding regions; (2) concatenated nucleotide sequences of 2 or more genes; and (3) genomic features, such as gene duplications, gene rearrangements, and changes in gene content and secondary structures of RNAs. To date, the mitochondrial genomes of over 700 species of multi-cellular animals have been sequenced entirely, however, only 24 of these species are parasitic arthropods. Of the mitochondrial genome markers, only the nucleotide sequences of 4 mitochondrial genes,cox1,cob,rrnSandrrnL, have been well explored in population genetic and evolutionary studies of parasitic arthropods whereas the sequences of the other 33 genes, and various genomic features have not. We review current knowledge of the mitochondrial genomes of parasitic arthropods, summarize applications of mitochondrial genes and genomic features in population genetic and evolutionary studies, and highlight prospects for future research.

Extraordinary number of gene rearrangements in the mitochondrial genomes of lice (Phthiraptera: Insecta)

The arrangement of genes in the mitochondrial (mt) genomes of most insects is the same, or near-identical, to that inferred to be ancestral for insects. We sequenced the entire mt genome of the small pigeon louse, Campanulotes bidentatus compar, and part of the mt genomes of nine other species of lice. These species were from six families and the three main suborders of the order Phthiraptera. There was no variation in gene arrangement among species within a family but there was much variation in gene arrangement among the three suborders of lice. There has been an extraordinary number of gene rearrangements in the mitochondrial genomes of lice!

The mitochondrial genomes of soft ticks have an arrangement of genes that has remained unchanged for over 400 million years

There are two major groups of ticks: soft ticks and hard ticks. The hard ticks comprise the prostriate ticks and the metastriate ticks. The mitochondrial (mt) genomes of one species of prostriate tick and two species of metastriate ticks had been sequenced prior to our study. The prostriate tick has the ancestral arrangement of mt genes of arthropods, whereas the two metastriate ticks have rearrangements of eight genes and duplicate control regions. However, the arrangement of genes in the mt genomes of soft ticks had not been studied. We sequenced the mt genomes of two species of soft ticks, Carios capensis and Ornithodoros moubata, and a metastriate tick, Haemaphysalis flava. We found that the soft ticks have the ancestral arrangement of mt genes of arthropods, whereas the metastriate tick, H. flava, shares the rearrangements of mt genes and duplicate control regions with the other two metastriate ticks that have previously been studied. Our study indicates that gene rearrangements and duplicate control regions in mt genomes occurred once in the most recent common ancestor of metastriate ticks, whereas the ancestral arrangement of arthropods has remained unchanged for over 400 million years in the lineages leading to the soft ticks and the prostriate ticks.

Crystallization and preliminary X-ray crystallographic studies of a macromolecular antitumour antibiotic, C1027

C1027 is a macromolecular antitumour antibiotic produced by Streptomyces globispourus C1027 and consists of an apoprotein and a non-protein labile chromophore. Little is known about how the thermally unstable chromophore is stabilized by the apoprotein. The purified C1027 was monodisperse according to dynamic light-scattering measurements and crystallized in two different crystal forms from two different starting conditions using the vapour-diffusion method. Condition I yielded hexagonal prism crystals having space group P3(1)/P3(2) and unit-cell parameters a = b = 66.8, c = 55.4 A. Diffraction data were collected to 2.1 A resolution using an in-house Rigaku rotating Cu anode X-ray generator. Another condition produced rod-like crystals with space group P3(1)21/P3(2)21 and unit-cell parameters a = b = 55.15, c = 55.87 A. A data set to 1.8 A resolution was collected from a rod-like crystal using a MAR CCD detector at the SRS synchrotron source.

Progesterone receptor antagonists Org 31710 and RU 486 increase apoptosis in human periovulatory granulosa cells

OBJECTIVE

To investigate if progesterone receptor (PR)-mediated effects are involved in regulating the susceptibility to apoptosis in LH receptor-stimulated human luteinizing granulosa cells.

DESIGN

Laboratory study.

SETTING

Göteborg University and an in vitro fertilization laboratory of a university hospital.

PATIENT(S)

Women undergoing oocyte retrieval for in vitro fertilization after ovulation induction with gonadotropins.

INTERVENTION(S)

Luteinizing granulosa cells were isolated from follicular aspirates after oocyte removal. The cells were treated with or without RU 486 (1 microM-100 microM), Org 31710 (1 microM-100 microM), progesterone (1 nM-10 microM), dexamethasone (0.5 microM-100 microM), dihydrotestosterone (1 nM-25 microM), RU 486 (10 microM-100 microM) + dexamethasone (50 microM), and picrotoxin (1 microM-100 microM) and were cultured under serum-free conditions.

MAIN OUTCOME MEASURE(S)

Measurement of caspase-3 activity; detection of internucleosomal DNA fragmentation using gel electrophoresis and fluorospectrophotometry; progesterone analysis of spent medium.

RESULT(S)

Addition of the PR antagonists RU 486 or Org 31710 in vitro to human luteinizing granulosa cells caused an increase in caspase-3 activity and a dose-dependent increase in internucleosomal DNA fragmentation. No effect on DNA fragmentation was seen after addition of dexamethasone, dihydrotestosterone, or picrotoxin.

CONCLUSION(S)

Nuclear PR-mediated effects are involved in regulating the susceptibility to apoptosis in LH receptor-stimulated human luteinizing granulosa cells.

E1A inhibition of radiation-induced NF-kappaB activity through suppression of IKK activity and IkappaB degradation, independent of Akt activation

Activation of the transcription factor nuclear factor kappaB (NF-kappaB) has been implicated in the protection of cells from apoptosis. We have shown previously that the adenovirus type 5 E1A sensitizes cells to radiation-induced apoptosis by inhibiting NF-kappaB activity. However, the exact mechanism of inhibition is not known. In this study, we compared the activity of inhibitor of nuclear factor-kappaB (IkappaB) kinase (IKK) and the degradation of IkappaBalpha in E1A transfectants and parental human cancer cells after ionizing radiation treatment. We found that radiation-induced IKK activity and IkappaBalpha degradation were inhibited in the E1A transfectants. Recently, Akt has been implicated in NF-kappaB activation. To test whether Akt is regulated by E1A and is involved in radiation-induced NF-kappaB activity, we examined the phosphorylation status of Akt in the E1A transfectants and parental cells and in irradiated cells. The results indicated that radiation induced Akt phosphorylation and that E1A inhibited basal but not radiation-induced Akt phosphorylation. We additionally examined radiation-induced NF-kappaB activity in cells stably transfected with a dominant-negative, inactive Akt and in parental cancer cells treated with a phosphatidylinositol 3-kinase inhibitor, wortmannin. We found that dominant-negative Akt and wortmannin did not block radiation-induced NF-kappaB activity. Thus, our results suggest that inhibition of IKK activity and IkappaB degradation is the predominant mechanism for E1A-mediated inhibition of radiation-induced NF-kappaB activity and that radiation-induced Akt activation cannot be inhibited by E1A and is likely independent of radiation-induced NF-kappaB activity.

p202, an interferon-inducible protein, mediates multiple antitumor activities in human pancreatic cancer xenograft models

p202, an IFN-inducible protein, interacts with certain transcriptional activators leading to transcriptional repression. p202 expression has been associated with inhibition of cancer cell growth in vitro and in vivo. To examine a potential p202-mediated antitumor activity in pancreatic cancer, we used both ectopic and orthotopic xenograft models and demonstrated that p202 expression is associated with multiple antitumor activities that include inhibition of tumor growth, reduced tumorigenicity, prolonged survival, and remarkably, suppression of metastasis and angiogenesis. In vitro invasion assay also showed that p202-expressing pancreatic cancer cells are less invasive than those without p202 expression. That observation was supported by the findings that p202-expressing tumors showed reduced expression of angiogenic markers, such as interleukin 8 and vascular endothelial growth factor, and p202-expressing pancreatic cancer cells have reduced level of matrix metalloproteinase-2 activity, a secreted protease activity important for metastasis. Importantly, we demonstrated a treatment efficacy by using p202/SN2 liposome complex in a nude mice xenograft model, suggesting a feasibility of using the p202/SN2 liposome in future preclinical gene therapy experiments. Together, our results strongly suggest that p202 expression mediates multiple antitumor activities against pancreatic cancer and may provide a scientific basis for developing a p202-based gene therapy in pancreatic cancer treatment.

p27 Kip1 inhibits HER2/neu-mediated cell growth and tumorigenesis

HER2/neu, a receptor tyrosine kinase oncogene, promotes mitogenic growth and transformation of cancer cells. We previously identified that its oncogenic signals down-regulate the cyclin-dependent kinase inhibitor p27 Kip1, which is defined as a haplo-insufficient tumor suppressor. Here, we applied the human p27 gene as a novel anticancer agent for HER2/neu-overexpressing cells under the control of a tetracycline (tet)-regulated gene expression system. Overexpression of p27 inhibits HER2/neu-activated CDK2 activity, cell proliferation, and transformation. Most significantly for clinical application, p27 expression in HER2/neu-overexpressing cells can be regulated in vivo and reduce the tumor volume in a tumor model. The findings demonstrate the applicability of employing p27 in HER2/neu-associated cancer gene therapy.

Numerous gene rearrangements in the mitochondrial genome of the wallaby louse, Heterodoxus macropus (Phthiraptera)

The complete arrangement of genes in the mitochondrial (mt) genome is known for 12 species of insects, and part of the gene arrangement in the mt genome is known for over 300 other species of insects. The arrangement of genes in the mt genome is very conserved in insects studied, since all of the protein-coding and rRNA genes and most of the tRNA genes are arranged in the same way. We sequenced the entire mt genome of the wallaby louse, Heterodoxus macropus, which is 14,670 bp long and has the 37 genes typical of animals and some noncoding regions. The largest noncoding region is 73 bp long (93% A+T), and the second largest is 47 bp long (92% A+T). Both of these noncoding regions seem to be able to form stem-loop structures. The arrangement of genes in the mt genome of this louse is unlike that of any other animal studied. All tRNA genes have moved and/or inverted relative to the ancestral gene arrangement of insects, which is present in the fruit fly Drosophila yakuba. At least nine protein-coding genes (atp6, atp8, cox2, cob, nad1-nad3, nad5, and nad6) have moved; moreover, four of these genes (atp6, atp8, nad1, and nad3) have inverted. The large number of gene rearrangements in the mt genome of H. macropus is unprecedented for an arthropod.

A ferroelectric liquid crystal conglomerate composed of racemic molecules

We describe the design and synthesis of a ferroelectric liquid crystal composed of racemic molecules. The ferroelectric polarization results from spontaneous polar symmetry breaking in a fluid smectic. The ferroelectric phase is also chiral, resulting in the formation of a mixture of macroscopic domains of either handedness at the isotropic-to-liquid crystal phase transition. This smectic liquid crystal is thus a fluid conglomerate. Detailed investigation of the electrooptic and polarization current behavior within individual domains in liquid crystal cells shows the thermodynamically stable structure to be a uniformly tilted smectic bow-phase (banana phase), with all layer pairs homochiral and ferroelectric (SmC(S)P(F)).

Inhibition of angiogenesis and induction of apoptosis are involved in E1A-mediated bystander effect and tumor suppression

Adenovirus type 5 E1A has been implicated in mediation of tumor suppression. Preclinical gene therapy studies have additionally shown that complete growth suppression can be achieved by incomplete transfer of E1A into tumors, suggesting that a bystander effect may also be associated with E1A. In this study, we investigated the E1A-mediated bystander effect and the mechanisms that may be associated with it. By s.c. inoculating nude mice with a mixture of E1A transfectants and parental cells, we found that the E1A transfectants exhibited a bystander effect on inhibition of tumor growth. We further showed that E1A mediated suppression of angiogenesis and induction of apoptosis in the tumors, likely contributing to the bystander effect. In addition, coculture of E1A transfectants and parental cells in a Transwell unit led to growth retardation and apoptosis mediated by the supernatant in the parental cells, indicating that a secreted factor may also contribute to the bystander effect. Taken together, our results suggested that E1A mediates a bystander effect on tumor suppression by inhibiting angiogenesis and inducing apoptosis.

Gene transfer of the neuronal NO synthase isoform to cirrhotic rat liver ameliorates portal hypertension

Reduced production of nitric oxide (NO) in the cirrhotic liver results from a defect in hepatic endothelial cell nitric oxide synthase (ecNOS) and appears to contribute to the high intrahepatic resistance and portal hypertension typical of cirrhosis. Therefore, we postulated that targeting a heterologous NOS isoform to sinusoidal endothelial cells or other perisinusoidal cells, such as hepatic stellate cells, would counter the defect in NO production and reduce resistance to blood flow. Recombinant adenovirus (Ad) carrying the neuronal NOS gene (nNOS) targeted liver sinusoidal endothelial cells, stellate cells, and hepatocytes more efficiently than the corresponding cells in cirrhotic livers, but transduction rates were substantial even in cirrhotic animals. Expression of nNOS in each liver cell type, whether from normal or injured liver, caused increased NO production and inhibited endothelin-1-induced contractility of perisinusoidal stellate cells. Finally, in 2 different in vivo models of cirrhosis and portal hypertension, transduction of livers with recombinant Ad.nNOS significantly reduced intrahepatic resistance and portal pressure. The data highlight the feasibility of gene transfer to diseased liver and hepatic cells and demonstrate the potential of a novel therapy for portal hypertension caused by cirrhosis.

The ets protein PEA3 suppresses HER-2/neu overexpression and inhibits tumorigenesis

Because HER-2/neu overexpression is important in cancer development, we looked for a method of suppressing the cell transformation mediated by HER-2/neu overexpression. We have identified that the DNA-binding protein PEA3, which is encoded by a previously isolated gene of the ets family, specifically targeted a DNA sequence on the HER-2/neu promoter and downregulated the promoter activity. Expression of PEA3 resulted in preferential inhibition of cell growth and tumor development of HER-2/neu-overexpressing cancer cells. This is a new approach to targeting HER-2/neu overexpression and also provides a rationale to the design for repressors of diseases caused by overexpression of pathogenic genes.

[Studies on schedules for human rabies immunization]

OBJECTIVES

To study the feasibility of interferon (INF) plus an immunization schedule of two dose-two dose-one dose (2 - 2 - 1) of rabies vaccine and a simple 2 - 2 - 1 schedule, and to explore immune regulation mechanism of INF.

METHODS

For an IFN plus 2 - 2 - 1 schedule, 5.0, 5.0 and 2.5 I.U. of primary hamster kidney cell rabies vaccine (PHKCV) were injected on the 1st, 7th and 14th day, respectively, and 0.2 million I.U. of IFN-alpha on the 1st day simultaneously. For a simple 2 - 2 - 1 schedule, only 5.0, 5.0 and 2.5 I.U. PHKCV were injected on the 1st, 7th and 14th day, respectively. And, for controls, a routine schedule recommended by WHO was used.

RESULTS

On the 7th day after immunization, their geometric mean titer (GMT) of antibody was 1.71, 1.57 and 1.21 for the above three schedule groups, respectively; on the 14th day, 62.77, 58.79 and 28.96; on the 45th day, 76.64, 72.90 and 62.22. Conversion rate of antibody was 85.00%, 61.11% and 65.00%, respectively on the 7th day, and was 100.00% for all on the 14th day. Proportion of those with protective antibody level was 10.00%, 0.00% and 0.00%, respectively for the three schedule groups, on the 7th day; 100.00%, 100.00% and 95.00%, on the 14th day; and was 100.00% for all on the 45th day. Proportion of those with antibody titer more than 1:1 was 55.00%, 33.33% and 20.00%, respectively, on the 7th day. Adverse reaction rate was 0.00% - 55.00%, without significant difference between three schedule groups.

CONCLUSIONS

Lower dose of IFN could enhance the effect of immune response to rabies vaccine. IFN plus 2 - 2 - 1 rabies vaccine schedule was better than that of simple 2 - 2 - 1 schedule, while the later was better than the routine schedule.

E1A-mediated paclitaxel sensitization in HER-2/neu-overexpressing ovarian cancer SKOV3.ip1 through apoptosis involving the caspase-3 pathway

HER-2/neu-overexpressing breast cancer cells are more resistant to the chemotherapeutic agent paclitaxel (Taxol) than low-HER-2/neu-expressing breast cancer cells, and the adenoviral type 5 EIA can down-regulate HER-2/neu overexpression. Therefore, in this study, we asked (a) whether EIA might sensitize response to paclitaxel in human HER-2/neu-overexpressing ovarian cancer cells, and, if so, what is the mechanism responsible; and (b) whether this enhanced chemosensitivity would translate into a therapeutic effect in an ovarian cancer xenograft model. Consequently, we demonstrated that: (a) adenovirus type 5 E1A could enhance the sensitivity of paclitaxel in paclitaxel-resistant HER-2/neu-overexpressing human ovarian cancer cells in vitro by inducing apoptosis, (b) this induction was heavily dependent on activation of the caspase-3 pathway, and (c) nude mice bearing i.p. HER-2/neu-overexpressing human ovarian cancer cells and treated with both paclitaxel and E1A gene therapy survived significantly longer than did mice treated only with paclitaxel or E1A gene therapy. Thus, we concluded that the E1A gene enhanced both the in vitro and in vivo sensitivity of paclitaxel in paclitaxel-resistant HER-2/ neu-overexpressing ovarian cancer SKOV3.ipl cells. Because a Phase I clinical trial using E1A gene targeted to HER-2/neu down-regulation has recently been completed, the current study also provided a scientific basis to further develop a novel therapy that combines paclitaxel and E1A gene therapy and its testing in a Phase II trial.

E1A sensitizes cells to tumor necrosis factor-induced apoptosis through inhibition of IkappaB kinases and nuclear factor kappaB activities

The adenovirus E1A protein has been implicated in increasing cellular susceptibility to apoptosis induced by tumor necrosis factor (TNF); however, its mechanism of action is still unknown. Since activation of nuclear factor kappaB (NF-kappaB) has been shown to play an anti-apoptotic role in TNF-induced apoptosis, we examined apoptotic susceptibility and NF-kappaB activation induced by TNF in the E1A transfectants and their parental cells. Here, we reported that E1A inhibited activation of NF-kappaB and rendered cells more sensitive to TNF-induced apoptosis. We further showed that this inhibition was through suppression of IkappaB kinase (IKK) activity and IkappaB phosphorylation. Moreover, deletion of the p300 and Rb binding domains of E1A abolished its function in blocking IKK activity and IkappaB phosphorylation, suggesting that these domains are essential for the E1A function in down-regulating IKK activity and NF-kappaB signaling. However, the role of E1A in inhibiting IKK activity might be indirect. Nevertheless, our results suggest that inhibition of IKK activity by E1A is an important mechanism for the E1A-mediated sensitization of TNF-induced apoptosis.

Collagen-homology domain 1 deletion mutant of Shc suppresses transformation mediated by neu through a MAPK-independent pathway

Shc proteins are implicated in coupling receptor tyrosine kinase to the mitogen-activated protein kinase (MAPK) pathway by recruiting Grb2/SOS to the plasma membrane. To better understand the role of Shc in the oncogenesis by point-mutation activated neu (p185*), we transfected a Shc mutant (ShcdeltaCHI), which lacks the Grb2 binding site Y317 by deletion of collagen-homology domain 1, into p185*-transformed NIH3T3 cells. The cellular transformation phenotypes were found to be largely suppressed by expression of ShcdeltaCH1. Although ShcdeltaCH1 still retained another Grb2 binding site (Y239/240), we did not detect its physical association with Grb2. We also found that ShcdeltaCH1 could associate with p185*; however, this association did not interfere with the endogenous Shc-p185* interaction or the Shc-Grb2 interaction. In addition, p185*-mediated MAPK and Elk activation likewise were not inhibited by ShcdeltaCH1 expression. Taken together, these data demonstrate that ShcdeltaCH1 suppresses the transformation induced by activated neu through a MAPK-independent pathway, indicating that Shc may be involved in other signal pathway(s) critical for cellular transformation in addition to the MAPK pathway.

Regulation of endothelin-1 synthesis by endothelin-converting enzyme-1 during wound healing

Endothelin-1 (ET-1) is involved in the pathogenesis of a number of diseases, including wound healing. In cirrhosis, the wounding response of the liver, circulating ET-1 levels are elevated; moreover, ET-1 has potent effects on hepatic stellate cells, the key effectors of cirrhosis. In this study, we have examined the regulatory role of ECE-1, a critical enzyme involved in ET-1 synthesis, in the two major cellular sources of hepatic ET-1. ET-1 release from normal hepatic endothelial cells was 25-fold higher than that from normal stellate cells. However, after liver injury, ET-1 release was increased in stellate cells but markedly decreased in endothelial cells. The two major isoforms of ECE-1, ECE-1alpha/1beta, made up 80% and 20%, respectively, of total ECE-1 in both stellate and endothelial cells. Following liver injury, ECE-1alpha mRNA was decreased by 44.2% in stellate cells, and by 16.1% in endothelial cells. ECE-1beta mRNA expression remained unchanged after injury. In contrast to ECE-1 mRNA, ECE-1 protein expression was increased by 43.9% in stellate cells but decreased in endothelial cells, while relative ECE-1 enzymatic activity was unchanged. In mRNA stability experiments, the half-life of ECE-1alpha mRNA in normal stellate cells was 13 h compared with 38 h in cells from injured livers. Thus, during hepatic wound healing, differential regulation of ECE-1 mRNA and protein appears to be critical in controlling ET-1 production.

Inhibition of nuclear factor-kappaB activity is involved in E1A-mediated sensitization of radiation-induced apoptosis

The adenoviral E1A protein has been implicated in the potentiation of apoptosis induced by various external stimuli, but the exact mechanism of that potentiation is not clear. In this study, we compared the sensitivity to ionizing gamma-irradiation of E1A transfectants with that of parental cells in a human ovarian cancer cell line (SKOV3.ip1); we found that the E1A transfectants became sensitive to radiation-induced apoptosis. Recently, activation of the transcription factor nuclear factor-kappaB (NF-kappaB) has been shown to play a key role in the anti-apoptotic pathway of radiation-induced apoptosis. In an attempt to determine whether NF-kappaB was involved in the E1A-mediated sensitization of radiation-induced apoptosis, we found that radiation-induced activation of NF-kappaB occurred in the parental cells but was blocked in the E1A transfectants. Furthermore, parental cells cotransfected with NF-kappaB and E1A were better protected from undergoing apoptosis upon irradiation than those transfected with E1A alone. Thus, our results suggest that inhibition of NF-kappaB activation by E1A is a plausible mechanism for E1A-mediated sensitization of radiation-induced apoptosis.

Spontaneous formation of macroscopic chiral domains in a fluid smectic phase of achiral molecules

A smectic liquid-crystal phase made from achiral molecules with bent cores was found to have fluid layers that exhibit two spontaneous symmetry-breaking instabilities: polar molecular orientational ordering about the layer normal and molecular tilt. These instabilities combine to form a chiral layer structure with a handedness that depends on the sign of the tilt. The bulk states are either antiferroelectric-racemic, with the layer polar direction and handedness alternating in sign from layer to layer, or antiferroelectric-chiral, which is of uniform layer handedness. Both states exhibit an electric field-induced transition from antiferroelectric to ferroelectric.

Coincubation of rat renal proximal tubules with hepatic subcellular fractions potentiates the effects of para-aminophenol

Treatment of rats with para-aminophenol (PAP) (300 mg/kg ip) produced decreases in renal nonprotein sulfhydryl (NPSH) content, oxygen consumption, and adenine nucleotide concentrations 2-4 hr following administration. In contrast, incubation of rat renal tubules with up to 1 mm PAP for 4 hr produced inconsistent changes in renal tubules. This discrepancy suggested that extrarenal metabolism of PAP may be involved in PAP bioactivation and nephrotoxicity. We designed the present studies to test the hypothesis that hepatic metabolism of PAP potentiates the effects of PAP on renal tubules. Incubation of renal tubules with 0.5 mm PAP and 10 mg protein from hepatic postmitochondrial supernatant (S9 fraction) in the absence of glutathione (GSH) for 4 hr did not alter renal oxygen consumption or adenine nucleotide metabolite concentrations. We observed no changes when we incubated tubules with 0.5 mm PAP and 1 mm GSH in the absence of hepatic S9 fraction. However, incubation of renal tubules with 0.5 mm PAP, 1 mm GSH, and 10 mg hepatic S9 protein for 4 hr significantly decreased renal oxygen consumption and adenosine triphosphate and total nucleotide concentrations. These data suggest that the effects of PAP in renal tubules may be potentiated by enzymatic metabolism of PAP, possibly involving oxidation and GSH conjugation. From experiments using hepatic microsomes or cytosol instead of S9 fraction, we found that changes were produced when we incubated tubules with PAP in the presence of hepatic microsomes, but not cytosol. These data suggest that hepatic microsomal metabolism of PAP may contribute to the production of changes in renal tubules in vitro. PAP-induced changes in renal proximal tubules were prevented when we included a beta-nicotinamide adenine dinucleotide phosphate (NADPH) generating system in the incubation medium. The protective effect of NADPH persisted when microsomes were inactivated by incubation with 1-aminobenzotriazole, a cytochrome P450 inhibitor. These data suggest that cytochrome P450-dependent oxidation is not involved in the production or prevention of PAP-induced changes in renal tubules. The enzyme(s) responsible for PAP bioactivation and the mechanism(s) by which NADPH protects renal tubules from PAP-induced decrements in oxygen consumption and adenine nucleotide concentrations are currently unclear.