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41.
Coinfection with human immunodeficiency virus type-1 (HIV-1) and hepatitis C virus (HCV) is a global problem that is more prevalent in injection drug users because they have a higher risk for acquiring both viruses. The roles of inflammatory cytokines and oxidative stress were examined in HIV-1- and HCV-coinfected human hepatic cells. Morphine (the bioactive product of heroin), HIV-1 Tat and the MN strain gp120 (gp120(MN)) proteins, and X4 HIV-1(LAI/IIIB) and R5 HIV-1(SF162) isolates were used to study the mechanisms of disease progression in HCV (JFH1)-infected Huh7.5.1 cell populations. HCV increased tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) release and augmented production of reactive oxygen species (ROS), nitric oxide (NO), and 3-nitrotyrosine (3-NT) in Huh7.5.1 cells. Morphine preferentially affected R5-tropic, but not X4-tropic, HIV-1 interactions with Huh7.5.1 cells. HIV-1 proteins or isolates increased cytokine release in HCV-infected cells, while adding morphine to coinfected cells caused complex imbalances, significantly disrupting cytokine secretion depending on the cytokine, morphine concentration, exposure duration, and particular pathogen involved. Production of ROS, NO, and 3-NT increased significantly in HCV- and HIV-1-coexposed cells while exposure to morphine further increased ROS. The proteasome inhibitor MG132 significantly decreased oxyradicals, cytokine levels, and HCV protein levels. Our findings indicate that hepatic inflammation is increased by combined exposure to HCV and HIV-1, that the ubiquitin-proteasome system and NF-κB contribute to key aspects of the response, and that morphine further exacerbates the disruption of host defenses. The results suggest that opioid abuse and HIV-1 coinfection each further accelerate HCV-mediated liver disease by dysregulating immune defenses. 相似文献
42.
Christina R?hr Martin Kerick Axel Fischer Alexander Kühn Karl Kashofer Bernd Timmermann Andriani Daskalaki Thomas Meinel Dmitriy Drichel Stefan T. B?rno Anja Nowka Sylvia Krobitsch Alice C. McHardy Christina Kratsch Tim Becker Andrea Wunderlich Christian Barmeyer Christian Viertler Kurt Zatloukal Christoph Wierling Hans Lehrach Michal R. Schweiger 《PloS one》2013,8(7)
MiRNAs are discussed as diagnostic and therapeutic molecules. However, effective miRNA drug treatments with miRNAs are, so far, hampered by the complexity of the miRNA networks. To identify potential miRNA drugs in colorectal cancer, we profiled miRNA and mRNA expression in matching normal, tumor and metastasis tissues of eight patients by Illumina sequencing. We validated six miRNAs in a large tissue screen containing 16 additional tumor entities and identified miRNA-1, miRNA-129, miRNA-497 and miRNA-215 as constantly de-regulated within the majority of cancers. Of these, we investigated miRNA-1 as representative in a systems-biology simulation of cellular cancer models implemented in PyBioS and assessed the effects of depletion as well as overexpression in terms of miRNA-1 as a potential treatment option. In this system, miRNA-1 treatment reverted the disease phenotype with different effectiveness among the patients. Scoring the gene expression changes obtained through mRNA-Seq from the same patients we show that the combination of deep sequencing and systems biological modeling can help to identify patient-specific responses to miRNA treatments. We present this data as guideline for future pre-clinical assessments of new and personalized therapeutic options. 相似文献
43.
John L. Markley Ad Bax Yoji Arata C. W. Hilbers Robert Kaptein Brian D. Sykes Peter E. Wright Kurt Wüthrich 《Journal of biomolecular NMR》1998,12(1):1-23
The recommendations presented here are designed to support easier communication of NMR data and NMR structures of proteins and nucleic acids through unified nomenclature and reporting standards. Much of this document pertains to the reporting of data in journal articles; however, in the interest of the future development of structural biology, it is desirable that the bulk of the reported information be stored in computer-accessible form and be freely accessible to the scientific community in standardized formats for data exchange. These recommendations stem from an IUPAC-IUBMB-IUPAB inter-union venture with the direct involvement of ICSU and CODATA. The Task Group has reviewed previous formal recommendations and has extended them in the light of more recent developments in the field of biomolecular NMR spectroscopy. Drafts of the recommendations presented here have been examined critically by more than 50 specialists in the field and have gone through two rounds of extensive modification to incorporate suggestions and criticisms. 相似文献
44.
Joy H. Meserve Jessica C. Nelson Kurt C. Marsden Jerry Hsu Fabio A. Echeverry Roshan A. Jain Marc A. Wolman Alberto E. Pereda Michael Granato 《PLoS genetics》2021,17(6)
The acoustic startle response is an evolutionarily conserved avoidance behavior. Disruptions in startle behavior, particularly startle magnitude, are a hallmark of several human neurological disorders. While the neural circuitry underlying startle behavior has been studied extensively, the repertoire of genes and genetic pathways that regulate this locomotor behavior has not been explored using an unbiased genetic approach. To identify such genes, we took advantage of the stereotypic startle behavior in zebrafish larvae and performed a forward genetic screen coupled with whole genome analysis. We uncovered mutations in eight genes critical for startle behavior, including two genes encoding proteins associated with human neurological disorders, Dolichol kinase (Dolk), a broadly expressed regulator of the glycoprotein biosynthesis pathway, and the potassium Shaker-like channel subunit Kv1.1. We demonstrate that Kv1.1 and Dolk play critical roles in the spinal cord to regulate movement magnitude during the startle response and spontaneous swim movements. Moreover, we show that Kv1.1 protein is mislocalized in dolk mutants, suggesting they act in a common genetic pathway. Combined, our results identify a diverse set of eight genes, all associated with human disorders, that regulate zebrafish startle behavior and reveal a previously unappreciated role for Dolk and Kv1.1 in regulating movement magnitude via a common genetic pathway. 相似文献
45.
Margaret A. Johnson Maurice W. Southworth Francine B. Perler Kurt Wüthrich 《Biomolecular NMR assignments》2007,1(1):19-21
The backbone and side chain resonance assignments of a precursor of the KlbA intein from Methanococcus jannaschii have been determined, based on triple-resonance experiments with the uniformly [13C,15N]-labeled protein. 相似文献
46.
Immune mechanisms in 2 strains of Salmo salar (Baltic salmon from River Ume Alv in Sweden and East Atlantic salmon from River Skjern? in Denmark) infected with the monogenean ectoparasite Gyrodactylus salaris were elucidated by molecular tools (real-time PCR). The gene expression in the fins (the preferred microhabitat of the parasite) of the susceptible but responding Swedish salmon was compared to the expression in the fins of the highly susceptible and nonresponding East Atlantic salmon. Experimental infections confirmed that both the Swedish and the Danish salmon allowed initial propagation of the parasite on the fins for a few weeks. Baltic salmon subsequently activated a response from Day 28 and limited the parasite population to a few parasites per host within the following weeks. In contrast, the Danish salmon did not respond and experienced a continuing increase in the parasite load during the same period, which reached several hundreds of parasites per host. RNA was isolated from fins of the 2 salmon strains during the course of infection and subsequent real-time PCR showed an increased expression of INFgamma, Mx and MHC I genes in Baltic salmon fins during large segments of the response phase. No upregulation of these genes could be detected in susceptible salmon. No increase in immunoglobulin genes was seen in any of the fish strains, which supports the notion that antibodies are not involved in the response. Further, the work suggests that cellular factors could at least partly contribute to the anti-parasitic response in Baltic salmon. 相似文献
47.
Deborah Merrick Tao Ting Lukas Kurt Josef Stadler Janet Smith 《BMC developmental biology》2007,7(1):65
Background
Fibre type specification is a poorly understood process beginning in embryogenesis in which skeletal muscle myotubes switch myosin-type to establish fast, slow and mixed fibre muscle groups with distinct function. Growth factors are required to establish slow fibres; it is unknown how fast twitch fibres are specified. Igf-2 is an embryonically expressed growth factor with established in vitro roles in skeletal muscle. Its localisation and role in embryonic muscle differentiation had not been established. 相似文献48.
Lun He Kurt J. Isselbacher Jack R. Wands Howard M. Goodman Chiaho Shih Andrea Quaroni 《In vitro cellular & developmental biology. Plant》1984,20(6):493-504
Summary A human hepatocellular carcinoma cell line (FOCUS—Friendship of China and United States) was derived from a patient with primary
hepatocellular carcinoma. This cell line has been in continuous culture over an 18-mo period. The morphological and ultrastructural
features of FOCUS are consistent with its neoplastic hepatocellular orgin. FOCUS cells contain aspartate aminotransferase
and glucose-6-phosphatase activity. In addition, α1-antitrypsin, fibrinogen, alpha fetoprotein, and carcinoembryonic antigens were detectble in the cytoplasm of the cultured
cells by immunochemical staining techniques. The karyotype of the FOCUS cell is human in origin and it contains human DNA
sequences as detected by molecular hybridization analysis. The FOCUS cells do not show evidence of density-dependent inhibition
of growth under confluent conditions. Repeated growth curves over an 18-mo period were identical, revealing a doubling time
of 42 to 48 h. The malignant potential of FOCUS cells was further demonstrated by their ability to lead to gross tumor formation
after subcutaneous infection into nude mice. From one of the solid tumors grown in nude mice, recultured cell lines have been
established and found to have properties identical to the original FOCUS cell line. This FOCUS cell line represents an additional
model for further investigation of tumor specific antigens and the relationship between hepatitis B virus (HBV) and hepatocellular
carcinoma. Preliminary molecular characterization has indicated the existence of integrated HBV sequences within the FOCUS
genome. 相似文献
49.
Kurt?J.?A.?Vanhoutte Doekele?G.?StavengaEmail author 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2005,191(5):461-473
The visual pigments in the compound eye of the comma butterfly, Polygonia c-album, were investigated in a specially designed epi-illumination microspectrophotometer. Absorption changes due to photochemical conversions of the visual pigments, or due to light-independent visual pigment decay and regeneration, were studied by measuring the eye shine, i.e., the light reflected from the tapetum located in each ommatidium proximal to the visual pigment-bearing rhabdom. The obtained absorbance difference spectra demonstrated the dominant presence of a green visual pigment. The rhodopsin and its metarhodopsin have absorption peak wavelengths at 532 nm and 492 nm, respectively. The metarhodopsin is removed from the rhabdom with a time constant of 15 min and the rhodopsin is regenerated with a time constant of 59 min (room temperature). A UV rhodopsin with metarhodopsin absorbing maximally at 467 nm was revealed, and evidence for a blue rhodopsin was obtained indirectly. 相似文献
50.
Butler DK All O Goffena J Loveless T Wilson T Toenjes KA 《Fungal genetics and biology : FG & B》2006,43(8):573-582
The opportunistic fungal pathogen Candida albicans can grow as yeast, pseudohyphae or true hyphae. C. albicans can switch between these morphologies in response to various environmental stimuli and this ability to switch is thought to be an important virulence trait. In Saccharomyces cerevisiae, the Grr1 protein is the substrate recognition component of an SCF ubiquitin ligase that regulates cell cycle progression, cell polarity and nutrient signaling. In this study, we have characterized the GRR1 gene of C. albicans. Deletion of GRR1 from the C. albicans genome results in a highly filamentous, pseudohyphal morphology under conditions that normally promote the yeast form of growth. Under hypha-inducing conditions, most cells lacking GRR1 retain a pseudohyphal morphology, but some cells appear to switch to hyphal-like growth and express the hypha-specific genes HWP1 and ECE1. The C. albicans GRR1 gene also complements the elongated cell morphology phenotype of an S. cerevisiae grr1Delta mutant, indicating that C. albicans GRR1 encodes a true orthologue of S. cerevisaie Grr1. These results support the hypothesis that the Grr1 protein of C. albicans, presumably as the F-box subunit of an SCF ubiquitin ligase, has an essential role in preventing the switch from the yeast cell morphology to a pseudohyphal morphology. 相似文献