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71.
Hovinen J 《化学与生物多样性》2006,3(3):296-303
The syntheses of three new aminooxy-tethered lanthanide(III) chelates, compounds 1-3, incorporating DOTA (= 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid), DTPA (= diethylenetriaminepentaacetic acid), or a substituted terpyridine (2,2',2',2'-[2,2': 6',2'-terpyridine-6,6'-diylbis(methylenenitrilo)]tetraacetic acid), respectively, are described. Reagents 1-3 can be used for carbonyl 'labeling', as shown by the formation of the corresponding oxime-ether bioconjugates of naltrexone (16) and 2-deoxy-beta-D-glucose (17) (Scheme 4). 相似文献
72.
Arto Y. Strandberg Fabian J. Hoti Timo E. Strandberg Solomon Christopher Jari Haukka Pasi Korhonen 《PloS one》2016,11(3)
Background
Insulin therapy in type 2 diabetes may increase mortality and cancer incidence, but the impact of different types of basal insulins on these endpoints is unclear. Compared to the traditional NPH insulin, the newer, longer-acting insulin analogues detemir and glargine have shown benefits in randomized controlled trials. Whether these advantages translate into lower mortality among users in real life is unknown.Objective
To estimate the differences in all-cause and cause-specific mortality rates between new users of basal insulins in a population-based study in Finland.Methods
23 751 individuals aged ≥40 with type 2 diabetes, who initiated basal insulin therapy in 2006–2009 were identified from national registers, with comprehensive data for mortality, causes of death, and background variables. Propensity score matching was performed on characteristics. Follow-up time was up to 4 years (median 1.7 years).Results
2078 deaths incurred. With NPH as reference, the adjusted HRs for all-cause mortality were 0.39 (95% CI, 0.30–0.50) for detemir, and 0.55 (95% CI, 0.44–0.69) for glargine. As compared to glargine, the HR was 0.71 (95% CI, 0.54–0.93) among detemir users. Compared to NPH, the mortality risk for both cardiovascular causes as well as cancer were also significantly lower for glargine, and especially for detemir in adjusted analysis. Furthermore, the results were robust in various sensitivity analyses.Conclusion
In real clinical practice, mortality was substantially higher among users of NPH insulin as compared to insulins detemir or glargine. Considering the large number of patients who require insulin therapy, this difference in risk may have major clinical and public health implications. Due to limitations of the observational study design, further investigation using an interventional study design is warranted. 相似文献73.
74.
Kaseva N Wehkalampi K Strang-Karlsson S Salonen M Pesonen AK Räikkönen K Tammelin T Hovi P Lahti J Heinonen K Järvenpää AL Andersson S Eriksson JG Kajantie E 《PloS one》2012,7(2):e32430
Background
Adults born preterm at very low birth weight (VLBW, <1500 g) have elevated levels of risk factors for cardiovascular diseases and type 2 diabetes. Preliminary observations suggest that this could partly be explained by lower rates of physical activity. The aim of this study was to assess physical activity in healthy young adults born preterm at very low birth weight compared with term-born controls.Methodology/Principal Findings
We studied 94 unimpaired young adults, aged 21–29 years, born at VLBW and 101 age-, sex-, and birth hospital-matched term-born controls from one regional center in Southern Finland. The participants completed a validated 30-item 12-month physical activity questionnaire and the NEO-Personality Inventory based on the Big Five taxonomy, the most commonly used classification of personality traits. Yearly frequency, total time, total volume and energy expenditure of conditioning and non-conditioning leisure-time physical activity (LTPA) and commuting physical activity were compared between VLBW and term-born subjects. A subset of participants underwent dual-energy x-ray absorptiometry for body composition measurement. Data were analyzed by multiple linear regression. Compared with controls, VLBW participants had lower frequency [−38.5% (95% CI; −58.9, −7.7)], total time [−47.4% (95% CI; −71.2, −4.1)], total volume [−44.3% (95% CI; −65.8, −9.2)] and energy expenditure [−55.9% (95% CI; −78.6, −9.4)] of conditioning LTPA when adjusted for age, sex, body mass index, smoking, parental education and personality traits. Adjusting for lean body mass instead of body mass index attenuated the difference. There were no differences in non-conditioning LTPA or commuting physical activity.Conclusions/Significance
Compared with term-born controls, unimpaired VLBW adults undertake less frequent LTPA with lower total time and volume of exercise resulting in lower energy expenditure. Differences in personality that exist between the VLBW and term-born groups do not seem to explain this association. 相似文献75.
dsRNA-mediated resistance to Beet Necrotic Yellow Vein Virus infections in sugar beet (Beta vulgaris L. ssp. vulgaris) 总被引:1,自引:0,他引:1
Britt-Louise Lennefors Eugene I. Savenkov Jan Bensefelt Elisabeth Wremerth-Weich Petra van Roggen Stig Tuvesson Jari P. T. Valkonen Jan Gielen 《Molecular breeding : new strategies in plant improvement》2006,18(4):313-325
Rhizomania, one of the most devastating diseases in sugar beet, is caused by Beet Necrotic Yellow Vein Virus (BNYVV) belonging to the genus Benyvirus. Use of sugar beet varieties with resistance to BNYVV is generally considered as the only way to maintain a profitable yield on rhizomania-infested fields. As an alternative to natural resistance, we explored the transgenic expression of viral dsRNA for engineering resistance to rhizomania. Transgenic plants expressing an inverted repeat of a 0.4 kb fragment derived from the BNYVV replicase gene displayed high levels of resistance against different genetic strains of BNYVV when inoculated using the natural vector, Polymyxa betae. The resistance was maintained under high infection pressures and over prolonged growing periods in the greenhouse as well as in the field. Resistant plants accumulated extremely low amounts of transgene mRNA and high amounts of the corresponding siRNA in the roots, illustrative of RNA silencing as the underlying mechanism. The transgenic resistance compared very favourably to natural sources of resistance to rhizomania and thus offers an attractive alternative for breeding resistant sugar beet varieties. 相似文献
76.
Mäkinen TM Raatikka VP Rytkönen M Jokelainen J Rintamäki H Ruuhela R Näyhä S Hassi J 《International journal of biometeorology》2006,51(1):27-36
The extent of outdoor exposure during winter and factors affecting it were examined in a cross-sectional population study in Finland. Men and women aged 25–74 years from the National FINRISK 2002 sub-study (n=6,591) were queried about their average weekly occupational, leisure-time and total cold exposure during the past winter. The effects of gender, age, area of residence, occupation, ambient temperature, self-rated health, physical activity and education on cold exposure were analysed. The self-reported median total cold exposure time was 7 h/week (8 h men, 6 h women),<1 h/week (2 h men, 0 h women) at work, 4 h/week (5 h men, 4 h women) during leisure time and 1 h/week (1 h men, 1.5 h women) while commuting to work. Factors associated with increased occupational cold exposure among men were: being employed in agriculture, forestry and industry/mining/construction or related occupations, being less educated and being aged 55–64 years. Factors associated with increased leisure-time cold exposure among men were: employment in industry/mining/construction or related occupations, being a pensioner or unemployed, reporting at least average health, being physically active and having college or vocational education. Among women, being a housewife, pensioner or unemployed and engaged in physical activity increased leisure-time cold exposure, and young women were more exposed than older ones. Self-rated health was positively associated with leisure time cold exposure in men and only to a minor extent in women. In conclusion, the subjects reported spending 4% of their total time under cold exposure, most of it (71%) during leisure time. Both occupational and leisure-time cold exposure is greater among men than women. 相似文献
77.
Intra J Cenni F Pavesi G Pasini M Perotti ME 《Molecular reproduction and development》2009,76(1):85-100
We have studied the presence of four sperm glycosidases, alpha-mannosidase, alpha-L- fucosidase and two beta-hexosaminidase isoforms, in 11 species of the genus Drosophila spanning approximately an evolutionary 60 MY period, and in Scaptodrosophila lebanonensis, belonging to the ancestor genus Scaptodrosophila. These enzymes had been previously identified in Drosophila melanogaster as putative receptors for glycoconjugates of the egg surface. Alpha-mannosidase and beta-hexosaminidases are intrinsic proteins of the sperm plasma membrane in species closely related to D. melanogaster as well as in the divergent species D. willistoni, D. hydei, D. virilis, and S. lebanonensis. Alpha-L-fucosidase is restricted to the species of the genus Drosophila. Alpha-mannosidase and beta-hexosaminidases have been purified and characterized in all species. Their molecular masses and optimal pHs are similar in all the species, whereas interspecific differences in enzyme activities were detected. Cross-species comparison of kinetic parameters indicated a relationship between enzyme efficiency and phylogenetic relatedness. Beta-hexosaminidases were the most efficient enzymes. Lectin cytochemistry suggested the presence of carbohydrate residues complementary to the glycosidases on the eggshell at the site of sperm entry in all species. Bioinformatic analysis of the coding sequences of beta-hexosaminases and alpha-L-fucosidase and of their predicted products showed no evidence of positive selection of the genes coding for these enzymes and a high degree of sequence identity of the predicted polypeptides among the species of the genus Drosophila. Collectively, our findings indicate that the Drosophila sperm glycosidases are structurally and functionally conserved and strengthen the hypothesis of their involvement in the interactions with the egg surface. 相似文献
78.
Potthast F Gerrits B Häkkinen J Rutishauser D Ahrens CH Roschitzki B Baerenfaller K Munton RP Walther P Gehrig P Seif P Seeberger PH Schlapbach R 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,854(1-2):173-182
We describe a statistical measure, Mass Distance Fingerprint, for automatic de novo detection of predominant peptide mass distances, i.e., putative protein modifications. The method's focus is to globally detect mass differences, not to assign peptide sequences or modifications to individual spectra. The Mass Distance Fingerprint is calculated from high accuracy measured peptide masses. For the data sets used in this study, known mass differences are detected at electron mass accuracy or better. The proposed method is novel because it works independently of protein sequence databases and without any prior knowledge about modifications. Both modified and unmodified peptides have to be present in the sample to be detected. The method can be used for automated detection of chemical/post-translational modifications, quality control of experiments and labeling approaches, and to control the modification settings of protein identification tools. The algorithm is implemented as a web application and is distributed as open source software. 相似文献
79.
Mataleena Parikka Milka M. Hammarén Sanna-Kaisa E. Harjula Nicholas J. A. Halfpenny Kaisa E. Oksanen Marika J. Lahtinen Elina T. Pajula Antti Iivanainen Marko Pesu Mika R?met 《PLoS pathogens》2012,8(9)
The mechanisms leading to latency and reactivation of human tuberculosis are still unclear, mainly due to the lack of standardized animal models for latent mycobacterial infection. In this longitudinal study of the progression of a mycobacterial disease in adult zebrafish, we show that an experimental intraperitoneal infection with a low dose (∼35 bacteria) of Mycobacterium marinum, results in the development of a latent disease in most individuals. The infection is characterized by limited mortality (25%), stable bacterial loads 4 weeks following infection and constant numbers of highly organized granulomas in few target organs. The majority of bacteria are dormant during a latent mycobacterial infection in zebrafish, and can be activated by resuscitation promoting factor ex vivo. In 5–10% of tuberculosis cases in humans, the disease is reactivated usually as a consequence of immune suppression. In our model, we are able to show that reactivation can be efficiently induced in infected zebrafish by γ-irradiation that transiently depletes granulo/monocyte and lymphocyte pools, as determined by flow cytometry. This immunosuppression causes reactivation of the dormant mycobacterial population and a rapid outgrowth of bacteria, leading to 88% mortality in four weeks. In this study, the adult zebrafish presents itself as a unique non-mammalian vertebrate model for studying the development of latency, regulation of mycobacterial dormancy, as well as reactivation of latent or subclinical tuberculosis. The possibilities for screening for host and pathogen factors affecting the disease progression, and identifying novel therapeutic agents and vaccine targets make this established model especially attractive. 相似文献
80.
Ylinen JJ Julin M Rezasoltani A Virtapohja H Kautiainen H Karila T Mälkiä E 《Journal of strength and conditioning research / National Strength & Conditioning Association》2003,17(4):755-759
Special training methods in wrestling have been assumed to improve the stability and tolerance of the neck. The aim of this study was to measure the neck strength levels reached in an extremely physically demanding sport. A neck strength measurement system was used to measure various parameters of maximal isometric neck strength in Finnish senior wrestlers competing at the international level. The results were compared with those achieved by junior wrestlers and a control group. The means (SD) of the maximal isometric neck strength for cervical rotation were 0.4 (0.1) Nm.kg(-1) for the senior wrestlers, 0.3 (0.1) Nm.kg(-1) for the junior wrestlers, and 0.2 (0.1) Nm.kg(-1) for the nonsportsmen. The respective results for cervical flexion were 4.4 (1.4), 3.8 (0.7), and 2.3 (0.8) Nm.kg(-1); for extension, 6.0 (1.1), 5.9 (0.7), and 4.0 (0.9) Nm.kg(-1). Neck strength in flexion seems to improve more than in extension as the result of wrestling. The greatest difference was found in rotation, which in the senior wrestlers was almost 3 times that in the nonsportsmen. There was great individual variation within all groups, and the results revealed weaknesses in all directions. Maximal neck strength measurements provide information useful in planning training programs to correct possible muscle deficiency and imbalance. 相似文献