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排序方式: 共有1618条查询结果,搜索用时 31 毫秒
151.
Masaki Tanabe Hiroshi Nakajima Akiko Nakamura Takayasu Ito Mashio Nakamura Takatsugu Shimono Hideo Wada Hideto Shimpo Tsutomu Nobori Masaaki Ito 《Journal of clinical microbiology》2009,47(7):2340-2343
Legionella anisa is rarely associated with human disease. Its gene was identified by broad-range PCR in whole blood and excised tissue from a patient with a culture-negative mycotic aneurysm and was considered as a possible pathogen. This case report is potentially useful for the future diagnosis of intravascular infection. 相似文献
152.
Tomoaki Kurosaki Takashi Kitahara Shigeru Kawakami Koyo Nishida Junzo Nakamura Mugen Teshima Hiroo Nakagawa Yukinobu Kodama Hideto To Hitoshi Sasaki 《Biomaterials》2009,30(26):4427-4434
The purpose of this study was to develop a gene vector electrostatically assembled with a polysaccharide capsule. We used pDNA/polyethylenimine (PEI) complexes as efficient non-viral vectors. The pDNA/PEI complex was electrostatically encapsulated with various polysaccharides such as fucoidan, λ-carrageenan, xanthan gum, alginic acid, hyaluronic acid, and chondroitin sulfate (CS). The pDNA/PEI complex was shown as nanoparticles with positive ζ-potential, although the ternary complexes encapsulated with polysaccharides were shown as nanoparticles with negative ζ-potential. The pDNA/PEI complex showed high agglutination activity and cytotoxicity, although the ternary complexes encapsulated with polysaccharides had no agglutination activities and lower cytotoxicities. The pDNA/PEI complex showed high uptake and high transgene efficiency in B16-F10 cells. On the other hand, most of the ternary complexes show little uptake and gene expression. The ternary complex encapsulated by CS, however, showed comparable transgene efficiency to the pDNA/PEI complex. The uptake and gene expression of the ternary complex encapsulated by CS were significantly inhibited by hypothermia and the addition of CS, suggesting that the ternary complex was taken by CS-specific receptor-mediated energy-dependent process. 相似文献
153.
Konnai S Nakajima C Imamura S Yamada S Nishikado H Kodama M Onuma M Ohashi K 《Immunology》2009,126(2):209-219
Previously, a putative immunosuppressant-coding gene was identified from a complementary DNA library derived from the salivary glands of partially-fed Haemaphysalis longicornis. Using real-time polymerase chain reaction, the gene was shown to be predominantly expressed during blood feeding with the site of expression being mainly in the salivary glands; this was confirmed by Western blotting analysis. To investigate the function of this novel protein, in this study, we examined the proliferative responses of bovine mononuclear cells and murine splenic cells as well as the expression of profiles of several cytokines in these cells in the presence of the recombinant protein (H. longicornis-derived 36 000 molecular weight protein: rHL-p36). The addition of rHL-p36 at the beginning of the 72 hr cultivation period clearly inhibited proliferation of several mitogen-stimulated cells in a dose-dependent manner, with concomitantly significant down-regulation of messenger RNA levels for interleukin-2. The inhibitory response could be abrogated by blockage of HL-p36 with antibody, suggesting the direct involvement of rHL-p36 in the cell proliferation. Furthermore, the proliferative response of splenocytes isolated from rHL-p36-inoculated mice was significantly lower than for those from control mice, suggesting that rHL-p36 could also directly suppress immune responses in vivo. Interestingly, microarray analysis of the splenocytes showed that the expression of several immunomodulating genes was down-regulated by rHL-p36 inoculation. In conclusion, these results suggest that HL-p36 is an immunosuppressor that might play an important role in the modulation of host immune responses. 相似文献
154.
N Tsutsumi S Kohnoe H Sonoda A Guntani T Rikimaru KI Taguchi M Tomikawa Y Kakeji H Nakashima Y Maehara 《Oncology letters》2011,2(5):791-796
Protein-bound polysaccharide-K (PSK) is a biological response modifier that possesses antitumor effects against various tumors. Although an inflammatory response has been considered to play an important role in the development of colorectal cancer, the anti-inflammatory effect of PSK has yet to be elucidated. An inflammatory bowel disease (IBD)-induced colorectal tumor model with 1.2-dimethyl hydrazine (DMH) and dextran sodium sulfate (DSS) was used to examine the effects of PSK on tumor suppression and survival. Although 90% of the mice that were not treated with PSK developed colitic tumors, oral administration of PSK suppressed tumor formation by less than 30%. Although deaths associated with DSS-induced melena were observed, PSK significantly reduced mortality. In conclusion, the present study showed that PSK not only suppressed colorectal tumor formation in the DMH+DSS-induced IBD model, but also improved the survival rate, indicating that anti-inflammatory activity is one of the mechanisms for the antitumor effects of PSK. 相似文献
155.
H Yoshiji R Noguchi Y Ikenaka K Kaji Y Shirai Y Aihara J Yamao M Toyohara A Mitoro M Sawai M Yoshida C Morioka M Fujimoto M Uemura H Kawaratani T Tsujimoto H Fukui 《Oncology letters》2011,2(1):69-73
The identification of biomarkers of anti-angiogenic therapy that predict clinical benefit is of vital importance. We previously reported that a combination treatment with clinically available safe agents, specifically angiotensin-converting enzyme inhibitor (ACE-I) and vitamin K (VK), inhibited the cumulative recurrence of hepatocellular carcinoma (HCC) via suppression of the vascular endothelial growth factor (VEGF). The present study aimed to identify non-invasive biological markers that predict the clinically beneficial effect of this combination regimen. A combination of ACE-I (perindopril; 4 mg/day) and VK (menatetrenone; 45 mg/day) was administered for 54 months following curative therapy for HCC. The cumulative recurrence and several indices, which are reportedly considered as biological markers of anti-angiogenic therapies, were analyzed. The combined treatment of ACE-I and VK markedly inhibited the cumulative recurrence of HCC during the 54-month follow-up. The serum VEGF and soluble VEGF receptor (sVEGFR)-2 were significantly suppressed with this combination regimen, whereas sVEGFR-1 was not. In HCC patients without recurrence, a significant suppression of VEGF and sVEGFR-2 was achieved within 6 and 3 months after treatment, respectively. In conclusion, the combination treatment of ACE-I and VK is a potentially novel anti-angiogenic strategy for secondary chemoprevention against HCC since the two agents are widely used in clinical practice without serious side effects. Furthermore, sVEGFR-2 may become a useful clinical predictive marker of this combination treatment. 相似文献
156.
157.
Yonenaga K Tohnai I Mitsudo K Mori Y Saijo H Iwai T Yonehara Y Ota Y Torigoe K Takato T 《International journal of clinical oncology / Japan Society of Clinical Oncology》2011,16(6):654-659
Background
The branching patterns of the external carotid artery vary among individuals, and consideration of the proximity of nerves is important during catheter insertion in superselective intra-arterial infusion via the superficial temporal artery. We aimed to evaluate the anatomy of the external carotid artery and its surrounding nerves for safe and accurate administration of superselective intra-arterial chemotherapy via the superficial temporal artery. 相似文献158.
Anaerobic NADH-fumarate reductase system is predominant in the respiratory chain of Echinococcus multilocularis, providing a novel target for the chemotherapy of alveolar echinococcosis
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Matsumoto J Sakamoto K Shinjyo N Kido Y Yamamoto N Yagi K Miyoshi H Nonaka N Katakura K Kita K Oku Y 《Antimicrobial agents and chemotherapy》2008,52(1):164-170
Alveolar echinococcosis, which is due to the massive growth of larval Echinococcus multilocularis, is a life-threatening parasitic zoonosis distributed widely across the northern hemisphere. Commercially available chemotherapeutic compounds have parasitostatic but not parasitocidal effects. Parasitic organisms use various energy metabolic pathways that differ greatly from those of their hosts and therefore could be promising targets for chemotherapy. The aim of this study was to characterize the mitochondrial respiratory chain of E. multilocularis, with the eventual goal of developing novel antiechinococcal compounds. Enzymatic analyses using enriched mitochondrial fractions from E. multilocularis protoscoleces revealed that the mitochondria exhibited NADH-fumarate reductase activity as the predominant enzyme activity, suggesting that the mitochondrial respiratory system of the parasite is highly adapted to anaerobic environments. High-performance liquid chromatography-mass spectrometry revealed that the primary quinone of the parasite mitochondria was rhodoquinone-10, which is commonly used as an electron mediator in anaerobic respiration by the NADH-fumarate reductase system of other eukaryotes. This also suggests that the mitochondria of E. multilocularis protoscoleces possess an anaerobic respiratory chain in which complex II of the parasite functions as a rhodoquinol-fumarate reductase. Furthermore, in vitro treatment assays using respiratory chain inhibitors against the NADH-quinone reductase activity of mitochondrial complex I demonstrated that they had a potent ability to kill protoscoleces. These results suggest that the mitochondrial respiratory chain of the parasite is a promising target for chemotherapy of alveolar echinococcosis. 相似文献
159.
Gen Kobashi Kaori Ohta Hideto Yamada Akira Hata Hisanori Minakami Noriaki Sakuragi Hiko Tamashiro Seiichiro Fujimoto the Hokkaido Perinatal Epidemiology Study Group 《Journal of epidemiology / Japan Epidemiological Association》2009,19(6):275-280
Background
Pregnancy-induced hypertension (PIH) is a common cause of perinatal mortality. It is believed to result from the interaction of several factors, including those related to the blood coagulation system. We performed genotyping and subgroup analyses to determine if the 4G/5G genotypes of the plasminogen activator inhibitor-1 gene (PAI-1) play a role in the pathogenesis of PIH, and to evaluate possible interactions of the PAI-1 polymorphisms with those of the angiotensinogen gene (AGT) and the endothelial nitric oxide synthase gene (NOS3).Methods
An association study of PAI-1 polymorphism, and subgroup analyses of common variants of AGT and NOS3, among 128 patients with PIH and 376 healthy pregnant controls.Results
No significant differences were found between the cases and controls in the frequencies of allele 4G or the 4G/4G genotype. In subgroup analyses, after adjustment for multiple comparison, a significant association with the AGT TT genotype was found among women with the PAI-1 4G/4G genotype, and an association with the NOS3 GA+AA genotype was found among women with the 5G/5G or 4G/5G genotypes.Conclusions
Our findings suggest that there are at least 2 pathways in the pathogenesis of severe PIH. However, with respect to early prediction and prevention of severe PIH, although the PAI-1 4G/4G genotype alone was not a risk factor for severe PIH, the fact that PAI-1 genotypes are associated with varying risks for severe PIH suggests that PAI-1 genotyping of pregnant women, in combination with other tests, may be useful in the development of individualized measures that may prevent severe PIH.Key words: pregnancy-induced hypertension, plasminogen activator inhibitor-1, angiotensinogen, endothelial nitric oxide synthase, gene polymorphism 相似文献160.
Takabayashi S Mitani Y Yokoyama K Shimpo H 《Interactive Cardiovascular and Thoracic Surgery》2008,7(2):328-330
A 19-day-old boy diagnosed with hypoplastic left heart syndrome underwent stage I bilateral pulmonary artery banding and main pulmonary artery-to-descending aorta shunt. A restrictive atrial septal defect existing before stage I recurred after balloon atrioseptostomy. After stage II Norwood and bidirectional Glenn procedure at age nine months, the Nakata index decreased to 73 mm(2)/m(2) (pulmonary artery mean pressure: 15 mmHg) and multiple systemic venous collaterals developed. Thus, we instituted oral sildenafil medication, and undertook surgical chest subcutaneous venous ligation and coil embolizations. Three years later, the Nakata index had increased to 117 mm(2)/m(2) (pulmonary artery mean pressure: 13 mmHg) and a Fontan procedure was successfully performed. 相似文献