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991.
We have previously described the antitumor reactivity of tumor-draining lymph node (TDLN) cells after secondary activation with antibodies. In this report, we examined the effects of interleukin (IL)-12 and IL-18 on modulating the immune function of antibody-activated murine TDLN cells. TDLN cells were activated with anti-CD3/anti-CD28 monoclonal antibody followed by stimulation with IL-12 and/or IL-18. IL-18 in combination with IL-12 showed a synergistic effect in augmenting IFNgamma and granulocyte macrophage colony-stimulating factor secretion, whereas IL-18 alone had minimal effect. Concurrently, IL-18 prevented IL-12-stimulated TDLN cells from producing IL-10. The IL-12/IL-18-cultured TDLN cells therefore manifested cytokine responses skewed towards a Th1/Tc1 pattern. IL-12 and IL-18 stimulated CD4(+) TDLN cells and enhanced IFNgamma production by CD4(+) cells to a greater extent than by CD8(+) cells. Use of NF-kappaB p50(-/-) TDLN cells suggested the involvement of NF-kappaB in the IL-12/IL-18 polarization effect. Furthermore, a specific NF-kappaB inhibitor significantly suppressed IL-12/IL-18-induced IFNgamma secretion, thus confirming the requirement for NF-kappaB activation in IL-12/IL-18 signaling. In adoptive immunotherapy, IL-12- and IL-18-cultured TDLN cells infiltrated pulmonary tumor nodules and eradicated established tumor metastases more efficiently than T cells generated with IL-12 or IL-18 alone. Antibody depletion revealed that both CD4(+) and CD8(+) cells were involved in the tumor rejection induced by IL-12/IL-18-cultured TDLN cells. These studies indicate that IL-12 and IL-18 can be used to generate potent CD4(+) and CD8(+) antitumor effector cells by synergistically polarizing antibody-activated TDLN cells towards a Th1 and Tc1 phenotype.  相似文献   
992.
Cancer-stromal interaction is well known to play important roles during cancer progression. Recently we have demonstrated that bone marrow-derived vascular endothelial cells (BMD-VE) and myofibroblasts (BMD-MF) are recruited into the human pancreatic cancer cell line Capan-1 induced stroma. To assess the effect of the difference in cancer cell types on the recruitment of BMD-VE and BMD-MF, 10 kinds of human cancer cell line were implanted into the subcutaneous tissue of the immunodeficient mice transplanted with bone marrow of double-mutant mice (RAG-1-/- beta-gal Tg or RAG-1-/- GFP Tg). The recruitment frequency of BMD-VE (%BMD-VE) and BMD-MF (%BMD-MF), and tumor-associated parameters [tumor volume (TV), microvessel density (MVD) and stromal proportion (%St)] were measured. The correlation among them was analyzed. Although %BMD-VE and %BMD-MF varied (from 0 to 21.6%, 0 to 29.6%, respectively), depending on the cancer cell line, both parameters were significantly correlated with %St (p < 0.005). Furthermore %BMD-VE and %BMD-MF also significantly correlated (p < 0.005). In order to assess the effect of tumor growth sites on the recruitment of the cells of interest, a human pancreatic cancer cell line, Capan-1, was transplanted into 5 different sites: subcutaneous tissue, peritoneum, liver, spleen and lung. Tumors in the subcutaneous tissue and peritoneum induced desmoplastic stroma (%St = 22.7%, 19.5%, respectively) and contained BMD-VE (%BMD-VE = 21.6%, 16.5% respectively) and BMD-MF (%BMD-MF = 29.6%, 24.5%, respectively), but weak stromal induction without recruitment of BMD-VE or -MF was observed in the tumors at of the liver, spleen and lung (%St = 9.7%, 9.1%, 5.4%, respectively). cDNA microarray analysis identified the 29 genes that expression was especially up- or down-regulated in the cell line that induced an abundant stromal reaction. However they did not encoded the molecules that were directly involved in stromal cell recruitment (chemokines), differentiation (cytokines) or proliferation (growth factors). These results indicate that the recruitment of BMD-VE and -MF is required for stromal formation during cancer progression and that the cancer microenvironment is important in stromal reaction and the recruitment of BMD-VE and -MF.  相似文献   
993.
994.
Heterocyclic amines are known to be important environmental carcinogens in several organs including the colon. The aim of this study was to induce colonic epithelial malignancies within a short-term period and analyze the expression of cycooxygenase (COX)-2, inducible nitric oxide synthase (iNOS) and beta-catenin, and mutations of beta-catenin gene in induced tumors. Male Crj: CD-1 mice were given a single i.g. administration (200 mg/kg body wt) of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) or 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) followed by 2% dextran sodium sulfate (DSS) in the drinking water for a week. The expression of beta-catenin, COX-2 and iNOS was immunohistochemically assessed in colonic epithelial lesions and the beta-catenin gene mutations in colonic adenocarcinomas induced were analyzed by the single strand conformation polymorphism method, restriction enzyme fragment length polymorphism and direct sequencing. At week 16, a high incidence of colonic neoplasms with dysplastic lesions developed in mice that received PhIP and DSS, but only a few developed in those given MeIQx and DSS. Immunohistochemically, the adenocarcinomas induced were all positive for three proteins. All seven adenocarcinomas induced by PhIP and DSS have mutations. The findings suggest that DSS exerts powerful tumor-promoting effects on PhIP-initiated colon carcinogenesis in mice and this mouse model is useful for investigating environment-related colon carcinogenesis within a short-term period.  相似文献   
995.

Background  

Influenza vaccination recently has been recommended for children 6–23 months old, but is not currently recommended for routine use in non-high-risk older children. Information on disease impact, costs, benefits, risks, and community preferences could help guide decisions about which age and risk groups should be vaccinated and strategies for improving coverage. The objective of this study was to measure preferences and willingness-to-pay for changes in health-related quality of life associated with uncomplicated influenza and two rarely-occurring vaccination-related adverse events (anaphylaxis and Guillain-Barré syndrome) in children.  相似文献   
996.
Tendency of isolated bacteria from infections in general surgery during the period from April 2003 to March 2004 were investigated in a multicenter study in Japan, and the following results were obtained. In this series, 455 strains including 14 strains of Candida spp. were isolated from 191(75.2%) of 254 patients with surgical infections. Two hundred and thirty-nine strains were isolated from primary infections, and 216 strains were isolated from postoperative infections. From primary infections, anaerobic Gram-positive bacteria and aerobic Gram-negative bacteria were predominant, while aerobic Gram-positive bacteria were predominant from postoperative infections. The isolation rate of aerobic Gram-positive bacteria, such as Enterococcus spp. and Staphylococcus aureus were higher from both types of infections. Among anaerobic Gram-positive bacteria, the isolation rate of Peptostreptococcus spp. was the highest from both types of infections. Among aerobic Gram-negative bacteria, Escherichia coli was the most predominantly isolated from primary infections, followed by Klebsiella pneumoniae, Enterobacter cloacae and Pseudomonas aeruginosa in this order, and from postoperative infections, E. coli was the most predominantly isolated, followed by P. aeruginosa, E. cloacae, and K. pneumoniae. Among anaerobic Gram-negative bacteria, the isolation rate of Bacteroides fragilis group was the highest from both types of infections. The isolation rate of anaerobic Gram-positive bacteria from primary infections and that of aerobic Gram-positive bacteria from postoperative infections were high in the last several years. In this series, we noticed no vancomycin-resistant Gram-positive cocci, but a few strains of moderately arbekacin-resistant MRSA. Carbapenm-resistant P. aeruginosa was seen in less than 10 per cents. Last year we noticed that there were cefazolin-resistant E. coli producing extended spectrum beta-lactamase, but there was no highly cefazolin-resistant E. coli in this year. In the next series, increase of both anaerobic bacteria and Enterococcus spp. should be carefully followed up.  相似文献   
997.
The susceptibilities of bacteria to fluoroquinolones (FQs), especially levofloxacin, and other antimicrobial agents were investigated using 11,475 clinical isolates collected in Japan during 2002. Methicillin susceptible staphylococci, Streptococcus pyogenes, Streptococcus pneumoniae, Moraxella catarrhalis, the family of Enterobactericeae, Haemophilus influenzae and Acinetobacter spp. exhibited stable and high susceptibilities to FQs. The rate of FQs-resistant MRSA was 80 approximately 90%, being markedly higher than that of FQs-resistant MSSA. The FQs-resistance rate of MRCNS was also higher than that of MSCNS, however, it was lower than that of MRSA. No FQs-resistant clinical isolates of Salmonella spp. were detected in any of the surveys. Thirteen of Escherichai coli 696 isolates, 8 of Klebsiella pneumoniae 630 isolates and 33 of Proteus mirabilis 373 isolates produced extended-spectrum beta-lactamase (ESBL), furthermore 6 of 13 in E. coli, 1 of 8 in K. pneumoniae and 14 of 31 ESBL-producing isolates, and in P. mirabilis were FQs resistant. Attention should be focused in the future on the emergence of ESBL in relation to FQs resistance. The rate of FQs-resistant P. aeruginosa isolated from urinary tract infection (UTI) was 40 approximately 60%, while 15 approximately 25% of isolates from respiratory tract infection (RTI) were resistant. IMP-1 type metallo beta-lactamase producing organisms were found in 49 of P. aeruginosa 1,095 isolates, 7 of S. marcescens 586 isolates and 4 of Acinetobacter spp. 474 isolates, respectively. Glycopeptide-resistant enterococci or S. aureus was not found.  相似文献   
998.
The antibacterial activity of meropenem (MEPM) and other parenteral antibiotics against clinical isolates of 907 strains of Gram-positive bacteria, 1790 strains of Gram-negative bacteria, and 192 strains of anaerobic bacteria obtained from 30 medical institutions during 2004 was measured. The results were as follows; 1. MIC90 of MEPM for almost all of enterobacteriaceae and Haemophilus influenzae were 4-fold to 32-fold lower than those of other carbapenems. MEPM was more active than other carbapenem antibiotics against Gram-negative bacteria, especially against enterobacteriaceae and H. influenzae. MEPM were active against most of the species tested in Gram-positive and anaerobic bacteria, except for multi-drug resistant strains including methicillin-resistant Staphylococcus aureus. 2. As for Pseudomonas aeruginosa, imipenem (IPM) showed high cross-resistant rate againt meropenem-resistant P. aeruginosa (87.9%). MEPM showed low cross-resistant rate both againt IPM-resistant P. aeruginosa (49.2%) and ciprofloxacin-resistant P. aeruginosa (38.0%). 3. The proportion of extended-spectrum beta-lactamase (ESBL) strains was 3.1% (4 strains) in Escherichia coli, 8.0% (2 strains) in Citrobacter koseri, 2.5% (3 strains) in Klebsiella pneumoniae, 2.5% (2 strains) in Enterobacter cloacae, 0.9% (1 strains) in Serratia marcescens, and 2.2% (2 strains) in Proteus mirabilis. The proportion of metallo-beta-lactamase strains was 1.6% (5 strains) in P. aeruginosa. 4. Of all species tested, Peptostreptococcus spp. was the only species, which MIC90 of MEPM was more than 4-fold higher than that in our previous study using clinical isolates during 2002 (0.25 microg/ml --> 1 microg/ml). Therefore, there is almost no siginificant decrease in susceptibility of clinical isolates to meropenem. In conclusion, the results from this surveillance study suggest that MEPM retains its potent and broad antibacterial activity and therefore is a clinically useful carbapenem at present, 9 years after available for commercial use.  相似文献   
999.
1 A novel muscarinic receptor antagonist, solifenacin succinate, inhibited specific binding of [N-methyl-(3)H]-scopolamine ([(3)H]-NMS) in the mouse bladder, submaxillary gland and heart in a concentration-dependent manner. This inhibitory effect was greatest in the submaxillary gland, followed by the bladder and heart. 2 After oral administration of oxybutynin (76.1 micromol kg(-1)) or solifenacin (62.4, 208 micromol kg(-1)), a significant dose- and time-dependent increase in K(D) values for specific [(3)H]-NMS binding was seen in the bladder, prostate, submaxillary gland, heart, colon and lung, compared with control values. The increase in K(D) induced by oxybutynin in each tissue reached a maximum 0.5 h after oral administration and then rapidly declined, while that induced by solifenacin was greatest 2 h after administration and was maintained for at least 6 or 12 h, depending on the dose. The muscarinic receptor binding of oral solifenacin was slower in onset and of a longer duration than that of oxybutynin. 3 Plasma concentrations of oxybutynin and its active metabolite (N-desethyl-oxybutynin, DEOB) were maximum 0.5 h after its oral administration and then declined rapidly. Oral solifenacin persisted in the blood for longer than oxybutynin. 4 Pilocarpine-induced salivary secretion in mice was significantly reduced by oral administration of solifenacin and was completely abolished 0.5 h after oral oxybutynin. Although the suppression induced by solifenacin was more persistent than that due to oxybutynin, the antagonistic effect of solifenacin on the dose-response curves to pilocarpine was significantly weaker than that of oxybutynin. It is concluded that oral solifenacin persistently binds to muscarinic receptors in tissues expressing the M(3) subtype, such as the bladder.  相似文献   
1000.
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