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251.
Claire M. Nightingale Alicja R. Rudnicka Christopher G. Owen Angela S. Donin Sian L. Newton Cheryl A. Furness Emma L. Howard Rachel D. Gillings Jonathan C. K. Wells Derek G. Cook Peter H. Whincup 《PloS one》2013,8(10)
Background
Bioelectrical impedance analysis (BIA) is a potentially valuable method for assessing lean mass and body fat levels in children from different ethnic groups. We examined the need for ethnic- and gender-specific equations for estimating fat free mass (FFM) from BIA in children from different ethnic groups and examined their effects on the assessment of ethnic differences in body fat.Methods
Cross-sectional study of children aged 8–10 years in London Primary schools including 325 South Asians, 250 black African-Caribbeans and 289 white Europeans with measurements of height, weight and arm-leg impedance (Z; Bodystat 1500). Total body water was estimated from deuterium dilution and converted to FFM. Multilevel models were used to derive three types of equation {A: FFM = linear combination(height+weight+Z); B: FFM = linear combination(height2/Z); C: FFM = linear combination(height2/Z+weight)}.Results
Ethnicity and gender were important predictors of FFM and improved model fit in all equations. The models of best fit were ethnicity and gender specific versions of equation A, followed by equation C; these provided accurate assessments of ethnic differences in FFM and FM. In contrast, the use of generic equations led to underestimation of both the negative South Asian-white European FFM difference and the positive black African-Caribbean-white European FFM difference (by 0.53 kg and by 0.73 kg respectively for equation A). The use of generic equations underestimated the positive South Asian-white European difference in fat mass (FM) and overestimated the positive black African-Caribbean-white European difference in FM (by 4.7% and 10.1% respectively for equation A). Consistent results were observed when the equations were applied to a large external data set.Conclusions
Ethnic- and gender-specific equations for predicting FFM from BIA provide better estimates of ethnic differences in FFM and FM in children, while generic equations can misrepresent these ethnic differences. 相似文献252.
Magdalena Gorska Antonella Marino Gammazza Michal Aleksander Zmijewski Claudia Campanella Francesco Cappello Tomasz Wasiewicz Alicja Kuban-Jankowska Agnieszka Daca Alicja Sielicka Urszula Popowska Narcyz Knap Jakub Antoniewicz Takashi Wakabayashi Michal Wozniak 《PloS one》2013,8(8)
Osteosarcoma is one of the most malignant tumors of childhood and adolescence that is often resistant to standard chemo- and radio-therapy. Geldanamycin and geldanamycin analogs have been recently studied as potential anticancer agents for osteosarcoma treatment. Here, for the first time, we have presented novel anticancer mechanisms of geldanamycin biological activity. Moreover, we demonstrated an association between the effects of geldanamycin on the major heat shock proteins (HSPs) and the overall survival of highly metastatic human osteosarcoma 143B cells. We demonstrated that the treatment of 143B cells with geldanamycin caused a subsequent upregulation of cytoplasmic Hsp90 and Hsp70 whose activity is at least partly responsible for cancer development and drug resistance. On the other hand, geldanamycin induced upregulation of Hsp60 gene expression, and a simultaneous loss of hyperacetylated Hsp60 mitochondrial protein pool resulting in decreased viability and augmented cancer cell death. Hyperacetylation of Hsp60 seems to be associated with anticancer activity of geldanamycin. In light of the fact that mitochondrial dysfunction plays a critical role in the apoptotic signaling pathway, the presented data may support a hypothesis that Hsp60 can be another functional part of mitochondria-related acetylome being a potential target for developing novel anticancer strategies. 相似文献
253.
Kaplan O Bezouška K Malandra A Veselá AB Petříčková A Felsberg J Rinágelová A Křen V Martínková L 《Biotechnology letters》2011,33(2):309-312
Purpose of work
Our aim is to describe new fungal nitrilases whose sequences were published but whose catalytic properties were unknown. We adapted for expression in E. coli three of the genes and confirmed that the enzymes acted on organic nitriles. 相似文献254.
255.
Hubalewska-Dydejczyk A Lewiński A Milewicz A Radowicki S Poręba R Karbownik-Lewińska M Kostecka-Matyja M Trofimiuk-Müldner M Pach D Zygmunt A Bandurska-Stankiewicz E Bar-Andziak E Bednarczuk T Buziak-Bereza M Drews K Gietka-Czernel M Górska M Jastrzębska H Junik R Nauman J Niedziela M Reroń A Sworczak K Syrenicz A Zgliczyński W 《Endokrynologia Polska》2011,62(4):362-381
The management of thyroid disorders during pregnancy is one of the most frequently disputed problems in modern endocrinology. It is widely known that thyroid dysfunction may result in subfertility, and, if inadequately treated during pregnancy, may cause obstetrical complications and influence fetal development. The 2007 Endocrine Society Practice Guideline endorsed with the participation of the Latino America Thyroid Association, the American Thyroid Association, the Asia and Oceania Thyroid Association and the European Thyroid Association, greatly contributed towards uniformity of the management of thyroid disorders during pregnancy and postpartum. Despite the tremendous progress in knowledge on the mutual influence of pregnancy and thyroid in health and disease, there are still important areas of uncertainty. There have been at least a few important studies published in the last 3 years, which influenced the thyroidal care of the expecting mother. It should also be remembered that guidelines may not always be universally applied in all populations with different ethnical, socio-economical, nutritional (including iodine intake) background or exposed to different iodine prophylaxis models. The Task Force for development of guidelines for thyroid dysfunction management in pregnant women was established in 2008. The expert group has recognized the following tasks: development of the coherent model of the management of thyroid dysfunction in pregnant women, identification of the group of women at risk of thyroid dysfunction, who may require endocrine care in the preconception period, during pregnancy and postpartum - that is in other words, the development of Polish recommendations for targeted thyroid disorder case finding during pregnancy, and the development of Polish trimester-specific reference values of thyroid hormones. Comprehensive Polish guidelines developed by the Task Force are to systematize the management of the thyroid disorders in pregnant women in Poland. 相似文献
256.
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259.
Cyplik P Schmidt M Szulc A Marecik R Lisiecki P Heipieper HJ Owsianiak M Vainshtein M Chrzanowski Ł 《Bioresource technology》2011,102(6):4347-4352
The degradation of diesel fuel, B20 blend and biodiesel in liquid cultures by a seven-member bacterial consortium was compared under conditions with full aeration or with limited aeration with nitrate added as main electron acceptor. Community dynamics was assessed employing real-time PCR and the ddCt method for relative quantification. Biodegradation rates increased with increasing biodiesel content, but were significantly reduced under conditions with nitrate. Despite large variations in biodegradation rates, magnitude changes in population numbers were typically observed only from zero to one order, regardless the type of fuel and electron acceptor. Only Comamonadaceae and Variovorax sp. distinctly preferred aerobic conditions, and during aerobic growth showed suppression as fuel contained more biodiesel. Thus, the consortium is relatively stable and most of the degraders can shift their metabolism from hydrocarbons to biodiesel. The stability of the consortium is of interest in the context of biodiesel-mediated biodegradation of petroleum hydrocarbons. 相似文献
260.