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991.
Wakasugi A Asakawa M Kogiso M Shimizu T Sato M Maitani Y 《International journal of pharmaceutics》2011,413(1-2):271-278
Organic nanotubes made of synthetic amphiphilic molecules are novel materials that form by self-assembly. In this study, organic nanotubes with a carboxyl group (ONTs) at the surface were used as a carrier for the anticancer drug doxorubicin, which has a weak amine group. The IC(50) values of ONT for cells were higher than that of conventional liposomes, suggesting that ONTs are safe. The results showed that the drug loading of ONTs was susceptible to the effect of ionic strength and H(+) concentration in the medium, and drug release from ONTs was promoted at lower pH, which is favorable for the release of drugs in the endosome after cellular uptake. ONTs loaded with the drug were internalized, and the drug was released quickly in the cells, as demonstrated on transmission electron microscopy images of ONTs and the detection of a 0.05% dose of ONT chelating gadolinium in the cells. Moreover, ONT could be modified chemically with folate by simply mixing with a folate-conjugate lipid. Therefore, these novel, biodegradable organic nanotubes have the potential to be used as drug carriers for controlled and targeting drug delivery. 相似文献
992.
993.
T Harada T Tanikawa Y Iwasaki M Yamada Y Imai M Miyake 《Biological & pharmaceutical bulletin》2012,35(9):1460-1468
Legionella pneumophila, a causative agent of Legionnaire's disease, is an intracellular pathogen. It intervenes in the signal transduction of macrophages by secreting effector molecules through the Icm/Dot type IV secretion system (T4SS). There is a connection between signaling cascades that regulate phagocytosis and the production of reactive oxygen species (ROS). Class I phosphatidylinositol 3-kinase (PI3-K) and its product phosphatidylinositol 3,4,5-trisphosphate (PI(3,4,5)P(3)) play key roles in the reorganization of cytoskeleton (phagocytosis) and activation of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (ROS production). We investigated the production of PI(3,4,5)P(3) and recruitment of class I PI3-K and Rac1 during phagocytosis of L. pneumophila by macrophages. Transient recruitment of class I PI3-K as well as PI(3,4,5)P(3) production was observed around a phagocytosed T4SS mutant LELA3118 or avirulent mutant 25D in an early stage of infection. In contrast, class I PI3-K was recruited while accumulation of PI(3,4,5)P(3) was not observed around wild type JR32. Immunoglobulin G (IgG)-opsonized live JR32, which would activate class I PI3-K through the Fcγ receptor pathway, did not induce PI(3,4,5)P(3) production. Regardless of whether wild type or mutants were used, transient Rac1 accumulation was observed around bacteria. These results indicate that the phagocytosis of wild type L. pneumophila occurs via a special mechanism in which PI(3,4,5)P(3) production is absent. This suggests that L. pneumophila may inhibit the production of PI(3,4,5)P(3), but not the recruitment of class I PI3-K and Rac1, in a T4SS-dependent manner. L. pneumophila may start the modulation of host signaling cascade immediately after contact with host cells to evade the ROS-dependent bactericidal system while completing entry into macrophages. 相似文献
994.
The process of wound healing involves complex interactions between circulating immune cells and local epithelial and endothelial cells. Studies in murine models indicate that cells of the innate immune system activated via their Toll-like receptors (TLR) can accelerate wound healing. This work examines whether immunostimulatory CpG oligodeoxynucleotides (ODN) designed to trigger human immune cells via TLR9 can promote the healing of excisional skin biopsies in rhesus macaques. Results indicate that 'K' type CpG ODN significantly accelerate wound closure in non-human primates (p < 0.05). Contributing to this outcome was a CpG-dependent increase in both the production of basic fibroblast growth factor and in keratinocyte migration. Of interest, IL-1α and TGFα normally present at sites of skin injury facilitated these effects. Current findings support the conclusion that the local administration of CpG ODN may provide an effective strategy for accelerating wound healing in humans. 相似文献
995.
Nakada T Kiyotani K Iwano S Uno T Yokohira M Yamakawa K Fujieda M Saito T Yamazaki H Imaida K Kamataki T 《The Journal of toxicological sciences》2012,37(3):555-563
We previously found that genetic polymorphism in cytochrome P450 2A6 (CYP2A6) is one of the potential determinants of tobacco-related lung cancer risk. It has been reported that the plasma concentration of cotinine, a major metabolite of nicotine, in carriers of wild-type alleles of CYP2A6 is considerably higher than that in carriers of null or reduced-function alleles of CYP2A6, raising the possibility that cotinine plays an important role in the development of lung cancer. As a novel mechanism of lung tumorigenesis mediated by CYP2A6, we investigated the effects of cotinine on the suppression of apoptosis and promotion of lung tumor growth. In human lung adenocarcinoma A549 cells, cotinine inhibited doxorubicin-induced cell death by suppressing caspase-mediated apoptosis. Enhanced phosphorylation of Akt, a key factor responsible for cell survival and inhibition of apoptosis, was detected after cotinine treatment. These data suggest that cotinine suppresses caspase-mediated apoptosis induced by doxorubicin through activation of the PI3K/Akt pathway. Furthermore, we clarified that cotinine significantly facilitated tumor growth in the Lewis lung cancer model and accelerated development of lung adenomas induced by 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone in A/J mice. We herein propose that cotinine induces tumor promotion by inhibiting apoptosis and enhancing cellular proliferation, thus underlining the importance of CYP2A6 in tobacco-related lung tumorigenesis. 相似文献
996.
Song Y H, Shiota M, Tamiya S, Kuroiwa K, Naito S & Tsuneyoshi M(2011) Histopathology 58 , 773–780 The significance of strong histone deacetylase 1 expression in the progression of prostate cancer Aims: Histone deacetylases (HDACs) play important roles in many types of cancer. Recently, it has been reported that HDAC1 expression in prostate cancer is significantly higher than in benign prostate cell lines and tissues. The expression of HDAC1 in association with the clinicopathological data was investigated to define its functional and pathological roles in prostate cancer. Methods and results: HDAC1 expression was examined immunohistochemically in 148 patients with prostate cancer. Strong expression of HDAC1 in benign prostate glands, high‐grade prostatic intraepithelial neoplasia (PIN) and prostate cancer was observed in 17/148 (11%), 19/71 (27%) and 69/148 (47%) patients. Strong HDAC1 expression was correlated with high Gleason score (P = 0.025) and high pT stage (P = 0.012). Patients with strong HDAC1 expression had higher biochemical recurrence rates (P = 0.0010). Furthermore, strong HDAC1 expression had a significant impact on patient biochemical recurrence rates in multivariate analysis (P = 0.004). Conclusions: These results indicate that overexpression of HDAC1 contributes to progression and poor prognosis in prostate cancer. The findings may play an important role in the emergence of effective new approaches for therapy and prognostic markers of prostate cancer. 相似文献
997.
Moritani S Ichihara S Hasegawa M Endo T Oiwa M Shiraiwa M Nishida C Morita T Sato Y Hayashi T Kato A Aoyama H Yoshikawa K 《Histopathology》2011,58(6):835-846
Moritani S, Ichihara S, Hasegawa M, Endo T, Oiwa M, Shiraiwa M, Nishida C, Morita T, Sato Y, Hayashi T, Kato A, Aoyama H & Yoshikawa K(2011) Histopathology 58 , 835–846 Topographical, morphological and immunohistochemical characteristics of carcinoma in situ of the breast involving sclerosing adenosis. Two distinct topographical patterns and histological types of carcinoma in situ Aim: To examine the histopathological features of 24 surgically resected carcinoma in situ (CIS) involving sclerosing adenosis (SA), with special reference to the topographical relationship between CIS and SA. Methods and results: In 13 (54%) lesions, CIS was entirely surrounded by SA (type A) and in 11 (46%), CIS involved SA at least focally but was not confined to the SA area (type B). The mean size of CIS in type B (30.45 mm) was significantly larger than in type A (18.00 mm). The mean size of SA in type A (39.46 mm) was significantly larger than in type B (19.54 mm). Most type A CIS were non‐high‐grade, and the oestrogen receptor (ER)(+)/progesterone receptor (PgR)(+)/HER2(?) immunophenotype predominated. Most type B CIS were high‐grade and six (54%) were ER(?)/PgR(?). Most type A were bcl‐2(+)/p53(?) in both SA and CIS areas, but two (18%) apocrine ductal CIS of type B were bcl‐2(?)/p53(+) in both SA and CIS areas. Expression of ER and cyclin D1 in SA was not different from that of SA unassociated with cancer. Conclusions: Most CIS involving SA arises within SA and high‐grade DCIS tends to grow beyond SA. Occasional CIS may arise outside SA and secondarily involve SA. 相似文献
998.
Yu H Tawab-Amiri A Dzutsev A Sabatino M Aleman K Yarchoan R Terabe M Sui Y Berzofsky JA 《Journal of leukocyte biology》2011,90(1):205-214
CD4(+) Th cells are important for the induction and maintenance of antigen-specific CD8(+) T cell function, so their loss or dysfunction in HIV-infected or cancer patients could reduce the patients' ability to control viral infection. Previous work in murine systems indicated that IL-15 codelivered with vaccines could overcome CD4(+) Th cell deficiency for induction of functionally efficient CD8(+) T cells and maintenance of viral-specific CTLs, but its efficacy in helping primary human CD8(+) T cell responses is unknown. In the present study, a peptide-pulsed, DC-based human coculture ex vivo system was used to study the role of IL-15 in overcoming CD4(+) Th deficiency to elicit CD8(+) T cell responses in CD4-depleted PBMCs from healthy individuals and PBMCs from HIV-1-infected patients. We found that IL-15 could overcome CD4(+) Th deficiency to induce primary and recall memory CD8(+) T cell responses in healthy individuals. Moreover, in CD4-deficient, HIV-1-infected patients with diminished CD8(+) T cell responses, IL-15 greatly enhanced CD8(+) T cell responses to alloantigen. These results suggest that IL-15 may be useful in the development of therapeutic and preventive vaccines against cancers and viral infections in patients defective in CD4(+) Th cell. 相似文献
999.
Yokoyama T Shimizu M Ikeno I Hashida Y Fujita S Shimura S Hatasaki K Shintani N Yachie A 《Nihon Rinshō Men'eki Gakkai kaishi》2011,34(2):105-111
The differential diagnosis of macrophage activation syndrome (MAS) and sepsis must be considered in the clinical course of systemic-onset juvenile idiopathic arthritis (s-JIA) with sudden onset of high-grade fever and abnormal laboratory findings, including leukocytopenia, thrombocytopenia, and coagulopathy. In this report, we describe the case of a 17-month-old girl diagnosed with s-JIA complicated with sepsis. Her serum interleukin (IL)-18 level was significantly elevated throughout the clinical course. Furthermore, compared to other MAS patients, she showed a significantly elevated serum IL-6 level and procalcitonin in sepsis. Therefore, our results suggest that a patient's cytokine profile may be a useful indicator of disease activity and may thus help in the differential diagnosis of sepsis and MAS in s-JIA. 相似文献
1000.