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51.
Modulation of the immune system by genetically modified immunological effector cells is of potential therapeutic value in the treatment of malignancies. Interleukin-2 (IL-2) is a crucial cytokine which induces potent antitumor response. Cytokine-induced killer cells (CIK) have been described as highly efficient cytotoxic effector cells capable of lysing tumor cell targets and are capable of recognizing these cells in a non-MHC restricted fashion. Dendritic cells (DC) are the major antigen presenting cells. This study evaluated the antitumor effect of CIK cells which were non-virally transfected with IL-2 and co-cultured with pulsed and unpulsed DC. Human CIK cells generated from peripheral blood were transfected in vitro with plasmid encoding for the human IL-2. Transfection involved a combination of electrical parameters and a specific solution to deliver plasmid directly to the cell nucleus by using the Nucleofector(R) electroporation system. Nucleofection resulted in the production of IL-2 with a mean of 478.5 pg/106 cells (range of 107.6-1079.3 pg /106 cells/24 h) compared to mock transfected CIK cells (31 pg/106 cells) (P = 0.05). After co-culturing with DC their functional ability was assessed in vitro by a cytotoxicity assay. On comparison with non-transfected CIK cells co-cultured with DCs (36.5 +/- 5.3 %), transfected CIK cells co-cultured with DC had a significantly higher lytic activity of 58.5 +/- 3.2% (P = 0.03) against Dan G cells, a human pancreatic carcinoma cell line. 相似文献
52.
Gram-positive bacteria, such as Staphylococcus aureus, cause serious human illnesses through combinations of surface virulence factors and secretion of exotoxins. Our prior studies using the protein synthesis inhibitor clindamycin and signal transduction inhibitors glycerol monolaurate and α-globin and β-globin chains of hemoglobin indicate that their abilities to inhibit exotoxin production by S. aureus are separable from abilities to inhibit growth of the organism. Additionally, our previous studies suggest that inhibition of exotoxin production, in absence of ability to kill S. aureus and normal flora lactobacilli, will prevent colonization by pathogenic S. aureus, while not interfering with lactobacilli colonization. These disparate activities may be important in development of novel anti-infective agents that do not alter normal flora. We initiated studies to explore the exotoxin-synthesis-inhibition activity of hemoglobin peptides further to develop potential agents to prevent S. aureus infections. We tested synthesized α-globin chain peptides, synthetic variants of α-globin chain peptides, and two human defensins for ability to inhibit exotoxin production without significantly inhibiting S. aureus growth. All of these peptides were weakly or not inhibitory to bacterial growth. However, the peptides were inhibitory to exotoxin production with increasing activity dependent on increasing numbers of positively-charged amino acids. Additionally, the peptides could be immobilized on agarose beads or have amino acid sequences scrambled and still retain exotoxin-synthesis-inhibition. The peptides are not toxic to human vaginal epithelial cells and do not inhibit growth of normal flora L. crispatus. These peptides may interfere with plasma membrane signal transduction in S. aureus due to their positive charges. 相似文献
53.
A survey of growth responses of tissue-culture cells to vitamins and amino acids was undertaken to explore the potentialities of tissue culture in the assay of growth factors. An antagonist of the nutrient was included in each test system to improve its sensitivity. Addition of an antimetabolite was advantageous in the thiamine and phenylalanine assays. Tissue-culture assays of tryptophan and of phenylalanine supplemented with β-2-thienylalanine compared favorably with microbial assays, and may serve as confirmatory or supplementary test systems. The sensitivity of cultured tissue cells to minute amounts of a variety of physiologically active substances suggests their employment in hormone and toxic compound assays. 相似文献
54.
In recent years, human genetic research has developed rapidly, and the cost of sequencing and computational technology continues to decline. This research has also been pushed forward by a major organizational innovation: the development of large, open-access databases of human gene sequences or biospecimens known as community resource projects. This article describes a challenge for the governance of these projects: conceptions of population vary significantly across organizational contexts. This makes it difficult to manage risk appropriately, as measures intended to address hazards to one kind of population may be inadequate for others. Unstable conceptions of population may also make it difficult to identify the stakeholders interested in the governance of these projects. This argument is developed by examining two cases, the International HapMap Project and 1000 Genomes Project, which make use of at least six distinct conceptions of population in different organizational segments. 相似文献
55.
Jimena Laporta Tonia L. Peters Kathryn E. Merriman Chad M. Vezina Laura L. Hernandez 《PloS one》2013,8(2)
The aim of this experiment was to demonstrate the ability of feeding serotonin (5-HT; 5-hydroxytryptamine) precursors to increase 5-HT production during the transition from pregnancy to lactation and the effects this has on maternal energy metabolism in the liver and mammary gland. Pregnant rats (n = 45) were fed one of three diets: I) control (CON), II) CON supplemented with 0.2% 5-hydroxytryptophan (5-HTP) or III) CON supplemented with 1.35% L-tryptophan (L-TRP), beginning on d13 of pregnancy through d9 of lactation (d9). Serum (pre and post-partum), milk (daily), liver and mammary gland tissue (d9) were collected. Serum 5-HT was increased in the 5-HTP fed dams beginning on d20 of gestation and remained elevated through d9, while it was only increased on d9 in the L-TRP fed dams. 5-HT levels were increased in mammary gland and liver of both groups. Additionally, 5-HTP fed dams had serum and milk glucose levels similar to the CON, while L-TRP had decreased serum (d9) and milk glucose (all dates evaluated). Feeding 5-HTP resulted in increased mRNA expression of key gluconeogenic and glycolytic enzymes in liver and glucose transporters 1 and 8 (GLUT-1, -8) in the mammary gland. We demonstrated the location of GLUT-8 in the mammary gland both in the epithelial and vascular endothelial cells. Finally, phosphorylated 5′ AMP-activated protein kinase (pAMPK), a known regulator of intracellular energy status, was elevated in mammary glands of 5-HTP fed dams. Our results suggest that increasing 5-HT production during the transition from pregnancy to lactation increases mRNA expression of enzymes involved in energy metabolism in the liver, and mRNA abundance and distribution of glucose transporters within the mammary gland. This suggests the possibility that 5-HT may be involved in regulating energy metabolism during the transition from pregnancy to lactation. 相似文献
56.
Amanda J. Brosnahan Joseph A. Merriman Wilmara Salgado-Pabón Bradley Ford Patrick M. Schlievert 《PloS one》2013,8(4)
The vaginal mucosa can be colonized by many bacteria including commensal organisms and potential pathogens, such as Staphylococcus aureus. Some strains of S. aureus produce the superantigen toxic shock syndrome toxin-1, which can penetrate the vaginal epithelium to cause toxic shock syndrome. We have observed that a female was mono-colonized with Enterococcus faecalis vaginally as tested in aerobic culture, even upon repeated culture for six months, suggesting this organism was negatively influencing colonization by other bacteria. In recent studies, we demonstrated an “outside-in” mechanism of cytokine signaling and consequent inflammation that facilitates the ability of potential pathogens to initiate infection from mucosal surfaces. Thus, we hypothesized that this strain of E. faecalis may make anti-inflammatory factors which block disease progression of more pathogenic organisms. E. faecalis MN1 inhibited interleukin-8 production from human vaginal epithelial cells in response to the vaginal pathogens Candida albicans, Gardnerella vaginalis, and Neisseria gonorrhoeae, as well as to toxic shock syndrome toxin-1. We further demonstrated that this organism secretes two tetramic acid compounds which appear responsible for inhibition of interleukin-8 production, as well as inhibition of T cell proliferation due to toxic shock syndrome toxin-1. Microbicides that include anti-inflammatory molecules, such as these tetramic acid compounds naturally produced by E. faecalis MN1, may be useful in prevention of diseases that develop from vaginal infections. 相似文献
57.
Cytotype regulation by telomeric P elements in Drosophila melanogaster: evidence for involvement of an RNA interference gene 总被引:1,自引:0,他引:1
P elements inserted at the left telomere of the X chromosome evoke the P cytotype, a maternally inherited condition that regulates the P-element family in the Drosophila germline. This regulation is completely disrupted in stocks heterozygous for mutations in aubergine, a gene whose protein product is involved in RNA interference. However, cytotype is not disrupted in stocks heterozygous for mutations in two other RNAi genes, piwi and homeless (spindle-E), or in a stock heterozygous for a mutation in the chromatin protein gene Enhancer of zeste. aubergine mutations exert their effects in the female germline, where the P cytotype is normally established and through which it is maintained. These effects are transmitted maternally to offspring of both sexes independently of the mutations themselves. Lines derived from mutant aubergine stocks reestablish the P cytotype quickly, unlike lines derived from stocks heterozygous for a mutation in Suppressor of variegation 205, the gene that encodes the telomere-capping protein HP1. Cytotype regulation by telomeric P elements may be tied to a system that uses RNAi to regulate the activities of telomeric retrotransposons in Drosophila. 相似文献
58.
Chen X Gorlov IP Ying J Merriman KW Kimmel M Lu C Reyes-Gibby CC Gorlova OY 《PloS one》2012,7(3):e32644
Background
Detection of early stage non-small cell lung cancer (NSCLC) is commonly believed to be incidental. Understanding the reasons that caused initial detection of these patients is important for early diagnosis. However, these reasons are not well studied.Methods
We retrospectively reviewed medical records of patients diagnosed with stage I or II NSCLC between 2000 and 2009 at UT MD Anderson Cancer Center. Information on suggestive LC-symptoms or other reasons that caused detection were extracted from patients'' medical records. We applied univariate and multivariate analyses to evaluate the association of suggestive LC-symptoms with tumor size and patient survival.Results
Of the 1396 early stage LC patients, 733 (52.5%) presented with suggestive LC-symptoms as chief complaint. 347 (24.9%) and 287 (20.6%) were diagnosed because of regular check-ups and evaluations for other diseases, respectively. The proportion of suggestive LC-symptom-caused detection had a linear relationship with the tumor size (correlation 0.96; with p<.0001). After age, gender, race, smoking status, therapy, and stage adjustment, the symptom-caused detection showed no significant difference in overall and LC-specific survival when compared with the other (non-symptom-caused) detection.Conclusion
Symptoms suggestive of LC are the number one reason that led to detection in early NSCLC. They were also associated with tumor size at diagnosis, suggesting early stage LC patients are developing symptoms. Presence of symptoms in early stages did not compromise survival. A symptom-based alerting system or guidelines may be worth of further study to benefit NSCLC high risk individuals. 相似文献59.
Alexander R Balasundaram A Batchelor M Brookings D Crépy K Crabbe T Deltent MF Driessens F Gill A Harris S Hutchinson G Kulisa C Merriman M Mistry P Parton T Turner J Whitcombe I Wright S 《Bioorganic & medicinal chemistry letters》2008,18(15):4316-4320
4-(1,3-Thiazol-2-yl)morpholine derivatives have been identified as potent and selective inhibitors of phosphoinositide 3-kinase. The SAR data of selected examples are presented and the in vivo profiling of compound 18 is shown to demonstrate the utility of this class of compounds in xenograft models of tumor growth. 相似文献
60.