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71.

Background

We investigated how four aspects of socio-demography influence the effectiveness of an intervention with structured personal diabetes care on long-term outcomes.

Methods

The Diabetes Care in General Practice (DCGP) study is a cluster-randomized trial involving a population-based sample of 1381 patients with newly diagnosed type 2-diabetes mellitus. We investigated how education, employment, cohabitation status and residence influenced the effectiveness of 6 years of intervention with structured personal diabetes care, resembling present day recommendations. Outcomes were incidence of any diabetes-related endpoint and death during 19 years after diagnosis, and cardiovascular risk factors, behaviour, attitudes and process-of-care variables 6 years after diagnosis.

Results

Structured personal care reduced the risk of any diabetes-related endpoint and the effect of the intervention was modified by geographical area (interaction p?=?0.034) with HR of 0.71 (95%CI: 0.60–0.85) and of 1.07 (95%CI: 0.77–1.48), for patients in urban and rural areas, respectively. Otherwise, there was no effect modification of education, employment and civil status on the intervention for the final endpoints. There were no noticeable socio-demographic differences in the effect of the intervention on cardiovascular risk factors, behaviour, attitudes, and process-of-care.

Conclusion

Structured personal care reduced the aggregate outcome of any diabetes-related endpoint and independent of socio-demographic factors similar effect on cardiovascular risk factors, behaviour, attitudes and process of care, but the intervention did not change the existing inequity in mortality and morbidity. Residence modified the uptake of the intervention with patients living in urban areas having more to gain of the intervention than rural patients, further investigations is warranted.

Trial registration

ClinicalTrials.gov registration no. NCT01074762 (February 24, 2010).
  相似文献   
72.
We argue the need to select indicator species on empirical data to avoid influence of personal opinions. To test an empirical selection process based on a nested subset matrix, we sampled partivoltine dragonfly larvae from 74 small lakes in central Sweden. A nestedness matrix was set up using the 'nestedness temperature calculator' program, selecting 11 species as potential indicators of species richness. These were tested against a known indicator species for water quality (the pool frog) and plant diversity through inventories and comparison to existing surveys of biological values ('rich' lakes vs. 'ordinary' lakes). We could only see a trend towards the pool frog occurring in dragonfly-rich lakes, but found a significant connection between the number of aquatic plants along the shore line and the number of dragonfly species present. A significantly higher number of indicators were encountered in lakes previously surveyed as 'rich' in plants than in lakes classified as 'ordinary'. Dragonfly species richness therefore appears to be positively associated with species richness of vascular plants. We propose nestedness matrices to be a good selecting tool for indicator species, particularly in groups where the biology of the species is not well known. However, it is important to define what such indicators really indicate.  相似文献   
73.
Abstract The cationic bactericidal peptides Pep 5 and nisin render membranes permeable to low- M r compounds. All Gram-positive bacteria treated with these peptides showed an immediate efflux of entrapped radioactive markers. The uptake of α-[14C]methylglucoside by the phosphoenolpyruvate-dependent phosphotransferase system was stimulated by Pep 5, supporting previous results that pep 5 abolishes the membrane potential. Oxygen consumption was inhibited, presumably due to lack of ADP. Escherichia coli became sensitive to Pep 5 and nisin when the outer membrane was bypassed by osmotic shock or by formation of cytoplasmic membrane vesicles. In contrast, Mycoplasma cells and erythrocytes were unaffected by Pep 5 and nisin in concentrations up to 1 mM. Human lung fibroblasts released only small amounts of ATP when treated with Pep 5 and nisin in μM concentrations. Eukaryotic and Mycoplasma cells were disrupted more effectively by the bee venom peptide melittin, which displays overall structural similarities to Pep 5 and nisin. Various artificial membranes were not affected by Pep 5, nisin, or melittin.  相似文献   
74.
It is generally assumed that type A lantibiotics primarily kill bacteria by permeabilization of the cytoplasmic membrane. As previous studies had demonstrated that nisin interacts with the membrane-bound peptidoglycan precursors lipid I and lipid II, we presumed that this interaction could play a role in the pore formation process of lantibiotics. Using a thin-layer chromatography system, we found that only nisin and epidermin, but not Pep5, can form a complex with [14C]-lipid II. Lipid II was then purified from Micrococcus luteus and incorporated into carboxyfluorescein-loaded liposomes made of phosphatidylcholine and cholesterol (1:1). Liposomes supplemented with 0.05 or 0.1 mol% of lipid II did not release any marker when treated with Pep5 or epilancin K7 (peptide concentrations of up to 5 mol% were tested). In contrast, as little as 0.01 mol% of epidermin and 0.1 mol% of nisin were sufficient to induce rapid marker release; phosphatidylglycerol-containing liposomes were even more susceptible. Controls with moenomycin-, undecaprenol- or dodecaprenolphosphate-doped liposomes demonstrated the specificity of the lantibiotics for lipid II. These results were correlated with intact cells in an in vivo model. M. luteus and Staphylococcus simulans were depleted of lipid II by preincubation with the lipopeptide ramoplanin and then tested for pore formation. When applied in concentrations below the minimal inhibitory concentration (MIC) and up to 5–10 times the MIC, the pore formation by nisin and epidermin was blocked; at higher concentrations of the lantibiotics the protective effect of ramoplanin disappeared. These results demonstrate that, in vitro and in vivo , lipid II serves as a docking molecule for nisin and epidermin, but not for Pep5 and epilancin K7, and thereby facilitates the formation of pores in the cytoplasmic membrane.  相似文献   
75.
76.
The lantibiotic Pep5 is produced by Staphylococcus epidermidis 5. Pep5 production and producer immunity are associated with the 20-kb plasmid pED503. A 1.3-kb KpnI fragment of pED503, containing the Pep5 structural gene pepA, was subcloned into the Escherichia coli-Staphylococcus shuttle vector pCU1, and the recombinant plasmid pMR2 was transferred to the Pep5- and immunity-negative mutant S. epidermidis 5 Pep5- (devoid of pED503). This clone did not produce active Pep5 but showed the same degree of insensitivity towards Pep5 as did the wild-type strain. Sequencing of the 1.3-kb KpnI-fragment and analysis of mutants demonstrated the involvement of two genes in Pep5 immunity, the structural gene pepA itself and pepI, a short open reading frame upstream of pepA. To identify the 69-amino-acid pepI gene product, we constructed an E. coli maltose-binding protein-PepI fusion clone. The immunity peptide PepI was detected in the soluble and membrane fractions of the wild-type strain and the immune mutants (harboring the plasmids pMR2 and pMR11) by immunoblotting with anti-maltose-binding protein-PepI antiserum. Strains harboring either pepI without pepA or pepI with incomplete pepA were not immune and did not produce PepI. Washing the membrane with salts and EDTA reduced the amount of PepI in this fraction, and treatment with Triton X-100 almost completely removed the peptide. Furthermore, PepI was hydrolyzed by proteases added to osmotically stabilized protoplasts. This suggests that PepI is loosely attached to the outside of the cytoplasmic membrane. Proline uptake and efflux experiments with immune and nonimmune strains also indicated that PepI may act at the membrane site.  相似文献   
77.
The human gene HSRAD51/RecA homologue has been investigated as a possible candidate gene involved in Bloom's syndrome. No mutations were found in the cDNA isolated from three different Bloom's syndrome cell lines, thus excluding the possibility that HSRAD51 is directly involved in the syndrome. Other possible candidates are discussed.  相似文献   
78.
79.
粘虫(Pseudaletia separata(Walker))生殖系统的解剖   总被引:2,自引:0,他引:2  
何继龙 《昆虫学报》1963,(3):282-291
本文内容是研究粘虫(Pseudaletia separata(Walker)生殖系统的形态构造。全文分为雄性内部生殖器、雄性外部生殖器、雌性内部生殖器及雌性外部生殖器四部分。 粘虫的雄性内生殖器中, 有睾丸一对, 左右并列, 呈扁椭圆形, 外被紫红色睾丸膜; 输精管一对, 基部膨大成二对贮精囊; 射精管分成复射精管及单射精管两部分。雄性外生殖器的构造极为复杂, 第9腹节的背、腹板分别形成马鞍状的背兜及基腹弧; 第10腹节仅有其附肢特化成钩形突、颚形突和背兜侧突等; 抱握器占雄性外生殖器中的大部分, 其顶上角具长约1毫米的端刺一枚, 此为本种特征之一, 可以此与近似种区别; 阳茎由基部球状的阳茎囊和端部柄状的阳茎端组成, 内具内阳茎及角状器:雄性外生殖器中有关器官的肌肉来源亦作了叙述。 精液是以贮存于精球的方式授入雌体, 精球分为精球体、精球柄及系带三部分。 雌性内生殖器中, 卵巢为多滋式, 一对, 各由四个卵巢管组成, 两组卵巢管再与一对侧输卵管相连, 后者通入中输卵管中, 中输卵管后端连有外生殖腔, 其外方的开口是为产卵孔; 受精囊为长形梨状物, 分成主囊及副囊两部分, 两者在顶部愈合, 并由此发出受精管与外生殖腔相通, 在主囊顶端有受精囊腺; 附腺一对, 与附腺囊相连, 后者通入附腺主囊, 并由此开口入外生殖腔。雌性外生殖器是由交配囊和产卵器组成, 前者复可分成囊导管、囊体及囊颈三部分, 其外方的开口为交配囊孔, 有导精管从囊颈连于外生殖腔; 产卵器由第8、9腹节组成, 非呈特殊构造。  相似文献   
80.
The increased abundance of large carnivores in Europe is a conservation success, but the impact on the behavior and population dynamics of prey species is generally unknown. In Europe, the recolonization of large carnivores often occurs in areas where humans have greatly modified the landscape through forestry or agriculture. Currently, we poorly understand the effects of recolonizing large carnivores on extant prey species in anthropogenic landscapes. Here, we investigated if ungulate prey species showed innate responses to the scent of a regionally exterminated but native large carnivore, and whether the responses were affected by human‐induced habitat openness. We experimentally introduced brown bear Ursus arctos scent to artificial feeding sites and used camera traps to document the responses of three sympatric ungulate species. In addition to controls without scent, reindeer scent Rangifer tarandus was used as a noncarnivore, novel control scent. Fallow deer Dama dama strongly avoided areas with bear scent. In the presence of bear scent, all ungulate species generally used open sites more than closed sites, whereas the opposite was observed at sites with reindeer scent or without scent. The opening of forest habitat by human practices, such as forestry and agriculture, creates a larger gradient in habitat openness than available in relatively unaffected closed forest systems, which may create opportunities for prey to alter their habitat selection and reduce predation risk in human‐modified systems that do not exist in more natural forest systems. Increased knowledge about antipredator responses in areas subjected to anthropogenic change is important because these responses may affect prey population dynamics, lower trophic levels, and attitudes toward large carnivores. These aspects may be of particular relevance in the light of the increasing wildlife populations across much of Europe.  相似文献   
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