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31.
The maturation/lysis (A2) protein encoded by the group B single-stranded RNA bacteriophage Qbeta mediates lysis of host Escherichia coli cells. We found a frameshift mutation in the replicase (beta-subunit) gene of Qbeta cDNA causes cell lysis. The mutant has a single base deletion 73 nucleotides (nt) 3' from the start of the replicase gene with consequent translation termination at a stop codon 129-131 nt further 3'. The 43-amino acid C-terminal part of the 67-amino acid product encoded by what in WT (wild-type) is the +1 frame, is rich in basic amino acids This 67-aa protein can mediate cell lysis whose characteristics indicate that the protein may cause lysis by a different mechanism and via a different target, than that caused by the A2 maturation/lysis protein. Synthesis of a counterpart of the newly discovered lysis product in wild-type phage infection would require a hypothetical ribosomal frameshifting event. The lysis gene of group A RNA phages is also short, 75 codons in MS2, and partially overlaps the first part of their equivalently located replicase gene, raising significant evolutionary implications for the present finding.  相似文献   
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OBJECTIVE: The aim of this study was to analyze the clinical and imaging characteristics in patients diagnosed with atypical endometrial hyperplasia based on endometrial biopsy in comparison with the final diagnosis from resected uteri; i.e. to determine the rates of underestimation (endometrial cancer), equivalent diagnosis (atypical hyperplasia), and overestimation (hyperplasia without atypia or non-hyperplastic lesion). MATERIALS AND METHODS: We reviewed 33 patients who were diagnosed with atypical endometrial hyperplasia by endometrial biopsy using a small curette and then underwent total abdominal hysterectomy between September 1992 and May 2002. Clinical parameters obtained from patients' charts, and imaging analyses using transvaginal ultrasonography (TUS) and magnetic resonance (MR) imaging were retrospectively re-examined. RESULTS: Among 33 patients who underwent hysterectomy due to a diagnosis of atypical hyperplasia, nine cases (27.2%) were underestimated (cancer), nine cases (27.2%) were equivalent and 15 cases (45.6%) were overestimated as indicated by examination of the endometrium of the resected uterus. There was no difference among these groups in either clinical parameters or diagnostic images obtained by TUS or MR. CONCLUSION: Diagnosis of atypical endometrial hyperplasia by endometrial biopsy often resulted in under- or over-estimation, as shown by examination after hysterectomy. As there is neither a reliable clinical parameter nor imaging feature to distinguish between these groups, hysterectomy is still the best treatment for these patients if they are willing to give up their fertility.  相似文献   
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Fetuin is a biocompatible plasma protein and strongly enhances phagocytosis of bacteria, DNA and apoptotic cells by peripheral blood cells such as monocytes, macrophages and dendritic cells. We developed a novel gene delivery system: ternary complexes constructed with pDNA, polyethylenimine (PEI) and fetuin. Without covalent binding, fetuin was able to coat pDNA–PEI complexes, and stable anionic nanoparticles formed at a weight ratio greater than 30. Optimised pDNA–PEI–fetuin complexes significantly decreased the cytotoxicity of pDNA–PEI complexes in the melanoma cell line B16F10. Furthermore, the pDNA–PEI–fetuin complexes had higher transgene efficiency compared to that of commercial lipofectin previously reported in B16F10 cells despite an anionic surface. The pDNA–PEI–fetuin complexes did not agglutinate with erythrocytes. The pDNA–PEI–fetuin complexes had high gene expression in the spleen after intravenous administration in mice. Thus, the pDNA–PEI–fetuin complexes were a useful in vivo gene delivery system with tropism for the spleen.  相似文献   
36.
Purpose The purpose of this study was to examine drug distribution in the liver after drug application to the rat liver surface.Methods Phenolsulfonphthalein (PSP) and fluorescein isothiocyanate dextran (MW 4400, FD-4) as model compounds or 5-fluorouracil (5-FU) was applied to the rat liver surface by employing a cylindrical diffusion cell (i.d. 9 mm, 0.64 cm2). Then, blood and the remaining solution in the diffusion cell were collected at selected times, followed by excision of the liver. The excised liver was divided into three sites: the region under the diffusion cell attachment site (site 1), the applied lobe except for site 1 (site 2), and non-applied lobes (site 3).Results In the case of i.v. administration, there were no differences in PSP concentrations among the three sites of the rat liver, and the concentrations rapidly decreased. On the other hand, the PSP concentration in site 1 after application to the rat liver surface was considerably higher than in site 2 and site 3. In addition, the area under the curve (AUC) value (AUCsite1), calculated from the PSP concentration profile in site 1, was about 10 times larger than that in site 3. A similar trend of regional delivery advantage by liver surface application was observed in the case of the macromolecule model FD-4, with a marked AUCsite1 of about 5 times larger than the other two sites. Moreover, we clarified that the anticancer drug 5-FU preferentially distributed in site 1 after application to the rat liver surface.Conclusion These results demonstrate the possibility of regional delivery of drugs to the liver by application to the liver surface.  相似文献   
37.
There is an urgent requirement for a novel vaccine that can stimulate immune responses without unwanted toxicity, including IgE elevation. We examined whether antigen ovalbumin (OVA) conjugated to the surface of nanoparticles (NPs) (OVA-NPs) with average diameter of 110 nm would serve as an immune adjuvant. When BALB/c mice were immunized with OVA-NPs, they developed sufficient levels of OVA-specific IgG1 antibody responses with low levels of IgE synthesis, representing helper T (Th)2-mediated humoral immunity. OVA-specific IgG2a and IgG2b responses (i.e., Th1-mediated immunity) were also induced by secondary immunization with OVA-NPs. As expected, immunization with OVA in alum (OVA-alum) stimulated humoral immune responses, including IgG1 and IgE antibodies, with only low levels of IgG2a/IgG2b antibodies. CD4-positive T cells from mice primed with OVA-NPs produced substantial levels of IL-21 and IL-4, comparable to those from OVA-alum group. The irradiated mice receiving OVA-NPs-primed B cells together with OVA-alum-primed T cells exhibited enhanced anti-OVA IgG2b responses relative to OVA-alum-primed B cells and T cells following stimulation with OVA-NPs. Moreover, when OVA-NPs-primed, but not OVA-alum-primed, B cells were cultured in the presence of anti-CD40 monoclonal antibody, IL-4, and IL-21, or LPS plus TGF-β in vitro, OVA-specific IgG1 or IgG2b antibody responses were elicited, suggesting that immunization with OVA-NPs modulates B cells to generate IgG1 and IgG2b responses. Thus, OVA-NPs might exert their adjuvant action on B cells, and they represent a promising potential vaccine for generating both IgG1 and IgG2a/IgG2b antibody responses with low IgE synthesis.  相似文献   
38.
Objectives The aim was to study the effect of viscous additives on the absorption and hepatic disposition of 5‐fluorouracil (5‐FU) after application to the liver surface in rats. Methods 5‐FU solution with or without viscous additives was applied to the rat liver surface with a cylindrical diffusion cell. Then, blood and the remaining solution in the diffusion cell were collected at selected times, followed by excision of the liver. The excised liver was divided into three sites and assayed for 5‐FU content. Key findings The absorption rate of 5‐FU from the liver surface was decreased in the presence of carboxymethylcellulose sodium (CMC‐Na) and polyvinyl alcohol (PVA) as compared with the control. The ka values of PVA 15% and CMC‐Na 1% were reduced to about 80 and 67% of the control. The maximum plasma concentration of 5‐FU was decreased by incorporation of viscous additives. The 5‐FU concentration at the diffusion cell attachment site of the liver (site 1) plateaued at 180 min in the absence of viscous additives. On the other hand, the concentration of 5‐FU at site 1 increased in a time‐dependent manner until 360 min in the presence of viscous additives. Conclusion Viscous additives might be useful for retaining drugs at their application site and controlling the rate of absorption from the liver surface.  相似文献   
39.
The aim of this report is to present the preliminary results of a Phase II study of high-dose (74 Gy RBE) proton beam therapy (PBT) with concurrent chemotherapy for unresectable locally advanced non-small-cell lung cancer (NSCLC). Patients were treated with PBT and chemotherapy with monthly cisplatin (on Day 1) and vinorelbine (on Days 1 and 8). The treatment doses were 74 Gy RBE for the primary site and 66 Gy RBE for the lymph nodes without elective lymph nodes. Adapted planning was made during the treatment. A total of 15 patients with Stage III NSCLC (IIIA: 4, IIIB: 11) were evaluated in this study. The median follow-up period was 21.7 months. None of the patients experienced Grade 4 or 5 non-hematologic toxicities. Acute pneumonitis was observed in three patients (Grade 1 in one, and Grade 3 in two), but Grade 3 pneumonitis was considered to be non-proton-related. Grade 3 acute esophagitis and dermatitis were observed in one and two patients, respectively. Severe ( ≥ Grade 3) leukocytopenia, neutropenia and thrombocytopenia were observed in 10 patients, seven patients and one patient, respectively. Late radiation Grades 2 and 3 pneumonitis was observed in one patient each. Six patients (40%) experienced local recurrence at the primary site and were treated with 74 Gy RBE. Disease progression was observed in 11 patients. The mean survival time was 26.7 months. We concluded that high-dose PBT with concurrent chemotherapy is safe to use in the treatment of unresectable Stage III NSCLC.  相似文献   
40.
The story of Roseto, Pennsylvania, USA, is one of the most widely cited studies of the putative influence of community social cohesion on population health. However, few contemporary studies of community-based "social capital" on health have addressed "communities" as unique places with unique histories outside of a Western context. In the present study, we focus on a specific region of Japan (which we call the M-region to preserve anonymity). Using survey data and qualitative interviews, we discuss the historical and contextual origins of the high social capital in the M-region that could account for its relatively good health profile. The analysis of survey data suggested that the residents of M-region have higher norms of reciprocity and participate more in horizontal organizations (including volunteer group, citizen or consumer group, sports group or club, and hobby group), and it also indicated better health status and behaviors in some outcomes among the residents of M-region. Based on qualitative interviews, the origins of social capital in the M-region appeared to be rooted in the strong sense of solidarity fostered by the fact that many of the residents were recruited into the region by the same local employer (a steel manufacturing company). Our study points to the need to ground studies of community-based "social capital" and health on detailed knowledge of the historical context of specific places.  相似文献   
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