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991.
Purpose: We examined whether bone marrow-derived dendritic cells (DCs) could induce antitumor immunity when a chemotherapeutic drug was added. Methods: CT26 (a murine colon cancer cell line syngeneic with BALB/c) and CT26-bearing mice were treated with mitomycin C (MMC) intraperitoneally (i.p.). Next, mice immunized with a coinjection of DCs and MMC-treated CT26 (i.p.) were given an intradermal inoculation of CT26. Finally, CT26-bearing mice were treated with MMC (i.p.) with or without DCs, given peritumorally. Results: Although the inoculated tumor was not rejected in the control mice, CT26 was rejected in 50% of the mice injected with MMC alone. Apoptosis was observed in the MMC-treated CT26 cells in vitro and in vivo. Immunization with DCs and apoptotic CT26 cells, but not with apoptotic CT26 alone, gave protection against tumor challenge in 7 of 13 mice. A significantly higher level of cytotoxic T-cell activity and interferon-γ production was seen in the protected mice. When MMC (i.p.) treatment was followed by peritumoral DC injection in the CT26-bearing mice, remarkable therapeutic effects were observed. Conclusion: DCs can collaborate with chemotherapy-induced apoptotic tumor cells and elicit improved antitumor immunity, probably through the acquisition of tumor-associated antigens from apoptotic tumor cells. Received: January 7, 2002 / Accepted: September 3, 2002 Acknowledgments. We thank Dr. Kazuo Kinoshita for his useful advice on using flow cytometry. This research was partly supported by the Ministry of Education, Culture, Sports, Science and Technology (No. 11671160). Reprint requests to: S. Yamasaki  相似文献   
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We report a case of rare multiple internal resorptions. Etiology of multiple internal resorptions is unknown. Interestingly, the patient had an atopic dermatitis, which is possibly related to multiple and rapid internal resorptions.  相似文献   
995.
Objective Pretargeting with radioactivity has significantly improved tumor to normal tissue radioactivity ratios over conventional antibody imaging in both animal studies and clinical trials. This laboratory is investigating DNA analogues such as phosphorodiamidate morpholinos (MORFs) for pretargeting using technetium-99m (99mTc) for detection. However, the unique properties of fluorescence activation and quenching combined with oligomers with their unique properties of hybridization may be particularly useful when used together for pretargeting with optical detection. The use of linear fluorophore-conjugated oligomer duplexes have been little used in animals, and to our knowledge, have not previously been considered for pretargeting applications. Methods A MORF/cDNA pair was selected such that when hybridized, the fluorescence of the Cy5.5-conjugated 25 mer MORF (Cy5.5–MORF25) is inhibited with a BHQ3-conjugated 18 mer complementary DNA (BHQ3–cDNA18). The short BHQ3–cDNA18 was selected to dissociate in the presence of a long cMORF25 in the pretargeted tumor, thus releasing the inhibitor from the Cy5.5 emitter. In this manner, the Cy5.5 fluorescence will be inhibited everywhere but in the target. The dissociation was first examined in vitro by adding the duplex to the cMORF25 both in solution and immobilized on polystyrene microspheres and by surface plasmon resonance (SPR). Thereafter, biotinylated cMORF25 immobilized on streptavidin polystyrene microspheres were administered intramuscularly in one thigh of hairless SKH-1 mice as target while an identical weight of the identical microspheres but without the cMORF25 was administered in the contralateral thigh as control. The animals then received IV the Cy5.5–MORF25/BHQ3–cDNA18 duplex or equal molar dosage of single-chain Cy5.5–MORF25 and were imaged. Results The SPR studies showed that the immobilized cDNA18 rapidly captured the flowing MORF25 to provide a duplex with a slow dissociation rate constant. Furthermore, when cMORF25 was next allowed to flow over the now immobilized duplex, the cDNA18 was unable to prevent dissociation of the heteroduplex and the formation and release of the cMORF25-MORF25 homoduplex. Images of animals obtained soon after receiving the Cy5.5–MORF25 singlet showed intense whole body fluorescence obscuring the target thigh. However, only 5 minutes after receiving the Cy5.5–MORF25/BHQ3–cDNA18 duplex, the target thigh was clearly visible along with only the kidneys. Conclusions This first study of optical pretargeting provides a proof of concept that oligomer pretargeting found to be useful with radioactivity detection is applicable with fluorescent detection as well. In addition, our results demonstrate that by using linear oligomers for optical pretargeting, chain lengths (and base sequences) may be manipulated to provide duplexes with stabilities and fluorescence inhibition optimized for pretargeting and other in vivo applications of optical imaging.  相似文献   
996.
Polymorphism p53 codon-72 and invasive cervical cancer: a meta-analysis.   总被引:4,自引:0,他引:4  
OBJECTIVES: Although some studies have reported that the arginine isoform on codon 72 of p53 increases the susceptibility to invasive cervical cancer, such data remain controversial. The objective of this study was to quantitatively summarize the evidence for such a relationship. METHODS: Our data sources consisted of a MEDLINE search of the literature published before December 2002, bibliography review, and expert consultation. Thirty-seven studies met the inclusion criteria. Information on sample size, study design, Hardy-Weinberg equilibrium, and method of genotype determination was abstracted by two reviewers using a standardized protocol. The overall odds ratio (OR) of the p53 gene on invasive cervical cancer was estimated using the Mantel-Haenzel method. RESULTS: The overall OR (95% confidence interval) for cervical cancer among those with the homozygous mutant (Arg/Arg) was 1.2 (1.1-1.3, P=0.001) compared with those with the heterozygous mutant (Arg/Pro). By a cellular type of cervical cancer, the overall OR among those with Arg/Arg was statistically significant in adenocarcinomas (1.7, 1.1-2.6, P=0.024), but not in squamous cell carcinomas (1.1, 0.9-1.2, P=0.960), compared with Pro/Pro. Compared with Arg/Pro, the OR among those with Arg/Arg was statistically significant in HPV types 16 (1,5, 1.2-2.0, P=0.002). CONCLUSIONS: Overall, the p53 gene was associated with increased risk for invasive cervical cancer. However, the risk varied by country, cellular, and HPV type.  相似文献   
997.
998.
Typhim Vi™ Vaccine   总被引:1,自引:1,他引:0  
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999.
Abstract For over 30 years now, research has been carried out to isolate and purify bone morphogenettc protein (BMP), a substance which has been shown to induce heterotopic bone formation in various animal species. Recent advances in the fields of developmental biology, molecular biology, genetics and wound healing, have shown that the BMPs are not only responsible for postfetal bone induction (including normal bone remodeling, healing and repair), but are also critical during embryogenesis, not only in regards to the skeletal system, but quite possibly in the morphogenesis and pattern formation of other tissues and organs as well, Therefore. BMPs have the potential as a therapeutic utility in orthopedic and dento-alveolar reconstruction.  相似文献   
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