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991.
The polysaccharide-based chiral packing materials (CPMs) for high-performance liquid chromatography (HPLC) have been recognized as the most powerful ones for the analyzing and preparative separating of the chiral compounds. These CPMs have been conventionally prepared by coating polysaccharide derivatives on a silica gel support. This means that the solvents, which swell or dissolve the derivatives on the silica gel and reduce the performance of the chiral columns, do not allow to be applied as components of the eluents. Therefore, the polysaccharide-based CPMs can be used with a rather limited number of eluents. In order to enhance the versatility of the eluent selection for more practical and economical chromatographic enantioseparations, the polysaccharide derivatives must be immobilized onto the silica gel. This review summarizes our latest studies on the development of the immobilized-type CPMs via the radical copolymerization and the polycondensation of the polysaccharide derivatives bearing small amounts of vinyl groups and alkoxysilyl groups, respectively.  相似文献   
992.
To determine functional regions of HIV-2 Vpx, we analyzed a series of site-specific vpx-mutants for their growth potentials in lymphocytic cells and compared the results with those in macrophages. We found that amino acid residues important for virus growth in lymphocytic cells, in macrophages, and in both are clustered separately in Vpx. Through generation and characterization of new vpx-mutants, we further demonstrated that a remarkable proline-stretch present at the C-terminus of Vpx is critical for its stable expression, thereby contributing to its functional activity. Taken together, there can be functionally distinct regions in HIV-2 Vpx.  相似文献   
993.
The Spontaneously Diabetic Torii (SDT) fatty rat, established by introducing the fa allele of the Zucker fatty rat into the SDT rat genome, is a new model of obese type 2 diabetes. The SDT-fa/fa (SDT fatty) rat shows overt obesity, and hyperglycemia and hyperlipidemia are observed at a young age as compared with the SDT-+/+ (SDT normal) rat. However, the features of the diabetic complications in the SDT fatty rat have not been reported. In the present study, the incidence and the progression of diabetic complications in the SDT fatty rat were examined, and compared with those of the SDT normal rat. Renal function parameters, such as blood urea nitrogen, urine volume and urinary protein, increased from 4 weeks of age in the SDT fatty rat, and pathological findings in the renal tubule were observed from 8 weeks. Furthermore, cataract was observed in the SDT fatty rat from 8 weeks of age, and prolongation of peak latencies on electroretinograms was observed at 16 and 24 weeks of age. On the other hand, in the SDT normal rat, renal or ocular changes were observed from 24 weeks of age. With early incidence of diabetes mellitus, diabetes-associated complications in the SDT fatty rat were seen at younger ages than those in the SDT normal rat. In conclusion, the SDT fatty rat is expected to be a useful model for the analysis of diabetic complications and the evaluation of drugs related to metabolic diseases.  相似文献   
994.

Background

The options for medical use of signaling molecules as stimulators of tissue regeneration are currently limited. Preclinical evidence suggests that fibroblast growth factor (FGF)-2 can promote periodontal regeneration. This study aimed to clarify the activity of FGF-2 in stimulating regeneration of periodontal tissue lost by periodontitis and to evaluate the safety of such stimulation.

Methodology/Principal Findings

We used recombinant human FGF-2 with 3% hydroxypropylcellulose (HPC) as vehicle and conducted a randomized double-blinded controlled trial involving 13 facilities. Subjects comprised 74 patients displaying a 2- or 3-walled vertical bone defect as measured ≥3 mm apical to the bone crest. Patients were randomly assigned to 4 groups: Group P, given HPC with no FGF-2; Group L, given HPC containing 0.03% FGF-2; Group M, given HPC containing 0.1% FGF-2; and Group H, given HPC containing 0.3% FGF-2. Each patient underwent flap operation during which we administered 200 µL of the appropriate investigational drug to the bone defect. Before and for 36 weeks following administration, patients underwent periodontal tissue inspections and standardized radiography of the region under investigation. As a result, a significant difference (p = 0.021) in rate of increase in alveolar bone height was identified between Group P (23.92%) and Group H (58.62%) at 36 weeks. The linear increase in alveolar bone height at 36 weeks in Group P and H was 0.95 mm and 1.85 mm, respectively (p = 0.132). No serious adverse events attributable to the investigational drug were identified.

Conclusions

Although no statistically significant differences were noted for gains in clinical attachment level and alveolar bone gain for FGF-2 groups versus Group P, the significant difference in rate of increase in alveolar bone height (p = 0.021) between Groups P and H at 36 weeks suggests that some efficacy could be expected from FGF-2 in stimulating regeneration of periodontal tissue in patients with periodontitis.

Trial Registration

ClinicalTrials.gov NCT00514657  相似文献   
995.
996.
We isolated 11 polymorphic microsatellites from blue coral (Heliopora coerulea), whose conservation and management are of great concern. The number of alleles ranged from 3 to 20 with an average of 5.5, and the observed and expected heterozygosities ranged from 0.115 to 0.833 and from 0.371 to 0.915, respectively. These loci are useful for conservation genetics in H. coerulea populations.  相似文献   
997.
Bordetella pertussis is the causative agent for human whooping cough. It was found that Bordetella pertussis infection caused a change in shape from flat to round in L2 cells, which are derived from rat type 2 alveolar cells. This phenomenon was reproduced using the culture supernatant of B. pertussis, and bacterium-free adenylate cyclase toxin (CyaA) was identified as the factor responsible. A purified preparation of wild-type CyaA but not an enzyme-dead mutant caused the cell rounding. It was examined whether CyaA causes similar morphological changes in various cultured cell lines. L2, EBL, HEK293T, MC3T3-E1, NIH 3T3, and Vero cells were rounded by the toxin whereas Caco-2, Eph4, and MDCK cells were not, although all these cells showed a significant elevation of the intracellular cAMP level in response to CyaA treatment, which indicates that there is no quantitative correlation between the rounding phenotype and the intracellular cAMP level. CyaA has been believed to target various immunocompetent cells and support the establishment of the bacterial infection by subverting the host immune responses. The possibility that CyaA may also affect tissue cells such as respiratory epithelial cells and may be involved in the pathogenesis of the bacterial infection is also indicated.  相似文献   
998.
It is known that the number of ImC, expressing myeloid markers, CD11b and Gr-1, increase with tumor growth and ImC play a role in the escape of tumor cells from immunosurveillance in tumor-bearing mice and cancer patients. However, the mechanisms by which ImC suppress immune responses in tumor-bearing mice have not been completely elucidated. In the present study, we investigated the function of splenic ImC freshly isolated from tumor-bearing mice and splenic ImC differentiated in vitro by GM-CSF. Freshly isolated splenic ImC were divided into two groups depending on Gr-1 expression, Gr-1 high (Gr-1hi) and intermediate (Gr-1int). Freshly isolated splenic Gr-1int ImC, but not Gr-1hi ImC, from tumor-bearing mice reduced production of IFN-γ in CD8+ T cells, but neither splenic Gr-1int ImC nor Gr-1hi ImC isolated from naive mice did. Both Gr-1int and Gr-1hi ImC differentiated in vitro by GM-CSF inhibited production of IFN-γ in both CD8+ and CD4+ T cells. In addition, the differentiated Gr-1int ImC, one-third of which were CD11c+F4/80+ cells, and their culture supernatants suppressed proliferative responses of T cells stimulated by CD3 ligation, but the differentiated Gr-1hi ImC and their culture supernatants did not. These results suggest that Gr-1int ImC are altered to immune-suppressive cells in tumor circumstances and that they are differentiated by GM-CSF progressively into CD11c+F4/80+ cells with further suppressive activity against T cells.  相似文献   
999.
Analysis of splenic Gr-1int immature myeloid cells in tumor-bearing mice.   总被引:1,自引:0,他引:1  
It is known that the number of ImC, expressing myeloid markers, CD11b and Gr-1, increase with tumor growth and ImC play a role in the escape of tumor cells from immunosurveillance in tumor-bearing mice and cancer patients. However, the mechanisms by which ImC suppress immune responses in tumor-bearing mice have not been completely elucidated. In the present study, we investigated the function of splenic ImC freshly isolated from tumor-bearing mice and splenic ImC differentiated in vitro by GM-CSF. Freshly isolated splenic ImC were divided into two groups depending on Gr-1 expression, Gr-1 high (Gr-1hi) and intermediate (Gr-1int). Freshly isolated splenic Gr-1int ImC, but not Gr-1hi ImC, from tumor-bearing mice reduced production of IFN-gamma in CD8+ T cells, but neither splenic Gr-1int ImC nor Gr-1hi ImC isolated from naive mice did. Both Gr-1int and Gr-1hi ImC differentiated in vitro by GM-CSF inhibited production of IFN-gamma in both CD8+ and CD4+ T cells. In addition, the differentiated Gr-1int ImC, one-third of which were CD11c+F4/80+ cells, and their culture supernatants suppressed proliferative responses of T cells stimulated by CD3 ligation, but the differentiated Gr-1hi ImC and their culture supernatants did not. These results suggest that Gr-1int ImC are altered to immune-suppressive cells in tumor circumstances and that they are differentiated by GM-CSF progressively into CD11c+F4/80+ cells with further suppressive activity against T cells.  相似文献   
1000.
Neuropeptide W (NPW) is an endogenous ligand for GPR7, a member of the G-protein-coupled receptor family. NPW plays an important role in the regulation of both feeding and energy metabolism, and is also implicated in modulating responses to an acute inflammatory pain through activation of the hypothalamus-pituitary-adrenal axis. GPR7 mRNA has been shown to be expressed in the hypothalamus, pituitary gland and adrenal cortex. Similarly, NPW expression has been demonstrated in the brain and pituitary gland. However, the precise distribution of NPW-producing cells in the adrenal gland remains unknown. The aim of this study was to explore the distribution and localization of NPW immunoreactivity in the rat adrenal gland. Total RNA was prepared from the hypothalamus, pituitary gland and adrenal gland. RT-PCR revealed the expression of NPW mRNA in these tissues, while in situ hybridization demonstrated the presence of NPW mRNA in the adrenal medulla. When immunohistochemistry was performed on sections of adrenal gland, NPW-like immunoreactivity (NPW-LI) was observed in the medulla but not in the cortex. Moreover, NPW-LI was found to be co-localized in cells which expressed dopamine beta hydroxylase but not phenylethanolamine-N-methyltransferase. The finding that NPW is expressed in noradrenalin-containing cells in the adrenal medulla suggests that it may play an important role in endocrine function in the adrenal gland.  相似文献   
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