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41.
42.

Aims

The palliative care has spread rapidly worldwide in the recent two decades. The development of hospice services in rural areas usually lags behind that in urban areas. The aim of our study was to investigate whether the urban-rural disparity widens in a country with a hospital-based hospice system.

Methods

From the nationwide claims database within the National Health Insurance in Taiwan, admissions to hospices from 2000 to 2006 were identified. Hospices and patients in each year were analyzed according to geographic location and residence.

Results

A total of 26,292 cancer patients had been admitted to hospices. The proportion of rural patients to all patients increased with time from 17.8% in 2000 to 25.7% in 2006. Although the numbers of beds and the utilizations in both urban and rural hospices expanded rapidly, the increasing trend in rural areas was more marked than that in urban areas. However, still two-thirds (898/1,357) of rural patients were admitted to urban hospices in 2006.

Conclusions

The gap of hospice utilizations between urban and rural areas in Taiwan did not widen with time. There was room for improvement in sufficient supply of rural hospices or efficient referral of rural patients.  相似文献   
43.
44.
Porphyromonas gingivalis is a major pathogen in the initiation and progression of periodontal disease, which is recognized as a common complication of diabetes. ICAM‐1 expression by human gingival fibroblasts (HGFs) is crucial for regulating local inflammatory responses in inflamed periodontal tissues. However, the effect of P. gingivalis in a high‐glucose situation in regulating HGF function is not understood. The P. gingivalis strain CCUG25226 was used to study the mechanisms underlying the modulation of HGF ICAM‐1 expression by invasion of high‐glucose‐treated P. gingivalis (HGPg). A high‐glucose condition upregulated fimA mRNA expression in P. gingivalis and increased its invasion ability in HGFs. HGF invasion with HGPg induced increases in the expression of ICAM‐1. By using specific inhibitors and short hairpin RNA (shRNA), we have demonstrated that the activation of p38 MAPK and Akt pathways is critical for HGPg‐induced ICAM‐1 expression. Luciferase reporters and chromatin immunoprecipitation assays suggest that HGPg invasion increases NF‐κB‐ and Sp1‐DNA‐binding activities in HGFs. Inhibition of NF‐κB and Sp1 activations blocked the HGPg‐induced ICAM‐1 promoter activity and expression. The effect of HGPg on HGF signalling and ICAM‐1 expression is mediated by CXC chemokine receptor 4 (CXCR4). Our findings identify the molecular pathways underlying HGPg‐dependent ICAM‐1 expression in HGFs, providing insight into the effect of P. gingivalis invasion in HGFs.  相似文献   
45.
Splicing of nuclear pre-mRNA occurs via two steps of the transesterification reaction, forming a lariat intermediate and product. The reactions are catalyzed by the spliceosome, a large ribonucleoprotein complex composed of five small nuclear RNAs and numerous protein factors. The spliceosome shares a similar catalytic core structure with that of fungal group II introns, which can self-splice using the same chemical mechanism. Like group II introns, both catalytic steps of pre-mRNA splicing can efficiently reverse on the affinity-purified spliceosome. The spliceosome also catalyzes a hydrolytic spliced-exon reopening reaction as observed in group II introns, indicating a strong link in their evolutionary relationship. We show here that, by arresting splicing after the first catalytic step, the purified spliceosome can catalyze debranching of lariat-intron-exon 2. The debranching reaction, although not observed in group II introns, has similar monovalent cation preferences as those for splicing catalysis of group II introns. The debranching reaction is in competition with the reverse Step 1 reaction influenced by the ionic environment and the structure of components binding near the catalytic center, suggesting that the catalytic center of the spliceosome can switch between different conformations to direct different chemical reactions.  相似文献   
46.

Background

We present the first comprehensive analysis of Mycobacterium tuberculosis (MTB) isolates circulating in southern Taiwan. In this 9-year population-based study, the TB situation in the Kaohsiung region was characterized by genotypic analysis of 421 MTB isolates.

Methods

All 421 isolates of MTB were analyzed by spoligotyping and MIRU-VNTR typing. Drug-resistance patterns were also analyzed.

Results

The percentage of EAI (East African-Indian) strains increased across sampling years (2000–2008) in southern Taiwan, whereas the proportion of Beijing lineages remained unchanged. Clustering was more frequent with EAI genotype infections (odds ratio = 3.6, p<0.0001) when compared to Beijing genotypes. Notably, MTB resistance to streptomycin (STR) had significantly increased over time, but resistance to other antibiotics, including multidrug resistance, had not. Three major genes (gidB, rpsL and rrs) implicated in STR resistance were sequenced and specific mutations identified.

Conclusions

This study revealed that EAI strains were highly transmissible and that STR resistance has increased between 2000 and 2008 in Kaohsiung, Taiwan.  相似文献   
47.
48.
We have reported the discovery of gambogic acid (GA) as a potent apoptosis inducer and the identification of transferrin receptor as its molecular target. In order to understand the basic pharmacophore of GA for inducing apoptosis and to discover novel and simplified derivatives as potential anti-cancer agents, we explored the synthesis of caged 2,3,3a,7a-tetrahydro-3,6-methanobenzofuran-7(6H)-ones (4-oxatricyclo[4.3.1.0]decan-2-ones). Three types of 2,3,3a,7a-tetrahydro-3,6-methanobenzofuran-7(6H)-ones based on xanthone, 2-phenylchromene-4-one and benzophenone, were synthesized using a Claisen/Diels-Alder reaction cascade. All the reactions produced the targeted caged compound as well as its neo-isomer. The caged compounds based on xanthone and 2-phenylchromene-4-one were found to maintain the apoptosis inducing and cell growth inhibiting activity of GA, although with less potency. The caged compounds based on benzophenone were found to be inactive. Our study determined the minimum structure of GA for its apoptosis inducing activity, which could lead to the development of simple derivatives as potential anti-cancer drugs.  相似文献   
49.
Characterization of alpha-actinin from Acanthamoeba   总被引:5,自引:0,他引:5  
Characterization of a protein from Acanthamoeba that was originally called gelation protein [T.D. Pollard, J. Biol. Chem. 256:7666-7670, 1981] has shown that it resembles the actin filament cross-linking protein, alpha-actinin, found in other cells. It comprises about 1.5% of the total amoeba protein and can be purified by chromatography with a yield of 13%. The native protein has a molecular weight of 180,000 and consists of two polypeptides of 90,000 Da. The Stokes' radius is 8.5 nm, the intrinsic viscosity is 0.35 dl/dm, and the extinction coefficient at 280 mm is 1.8 X 10(5)M-1 X cm-1. Electron micrographs of shadowed specimens show that the molecule is a rod 48 nm long and 7 nm wide with globular domains at both ends and in the middle of the shaft. On gel electrophoresis in sodium dodecylsulfate the pure protein can run as bands with apparent molecular weights of 60,000, 90,000, 95,000, or 134,000 depending on the method of sample preparation. Rabbit antibodies to electrophoretically purified Acanthamoeba alpha-actinin polypeptides react with all of these electrophoretic variants in samples of purified protein and cell extracts. By indirect fluorescent antibody staining of fixed amoebas, alpha-actinin is distributed throughout the cytoplasmic matrix and concentrated in the hyaline cytoplasm of the cortex. The protein cross-links actin filaments in the presence and absence of Ca++. It inhibits slightly the time course of the spontaneous polymerization of actin monomers but has no effect on the critical concentration for actin polymerization even though it increases the apparent rate of elongation to a small extent. Like some other cross-linking proteins, amoeba alpha-actinin inhibits the actin-activated ATPase of muscle myosin subfragment-1. Although Acanthamoeba alpha-actinin resembles the alpha-actinin from other cells in shape and ability to cross-link actin filaments, antibodies to amoeba and smooth muscle alpha-actinins do not cross react and there are substantial differences in the amino acid compositions and molecular dimensions.  相似文献   
50.
In this study, it was demonstrated, by using agar diffusion tests and a Transwell system, that Burkholderia multivorans NKI379 has an antagonistic effect against the growth of B. pseudomallei. Bacterial representatives were isolated from agricultural crop soil and mixed to construct a partial bacterial community structure that was based on the results of reproducible patterns following PCR-denaturing gradient gel electrophoresis analysis of total soil chromosomes. The antagonistic effect of B. multivorans on B. pseudomallei was observed in this imitate community. In a field study of agricultural crop soil, the presence of B. pseudomallei was inversely related to the presence of the antagonistic strains B. multivorans or B. cenocepacia. B. multivorans NKI379 can survive in a broader range of pH, temperatures and salt concentrations than B. pseudomallei, suggesting that B. multivorans can adapt to extreme environmental changes and therefore predominates over B. pseudomallei in natural environments.  相似文献   
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