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α-Lactalbumin α-La), together with oleic acid can be converted to a complex, which kills tumor cells selectively. Cytotoxic α-La -oleic acid and α-La -linoleic acid complexes were generated by adding fatty acid to camel holo α-La at 60 ° C (referred to as La-OA-60 and La-LA-60 state, respectively). Structural properties of these complexes were studied and compared to the camel α-La. The experimental results show that linoleic acid induces α-La partial unfolding but oleic acid does not change the protein structure significantly. Also the stability of La-OA-60 and La-LA-60 toward thermal denaturation was measured. The order of temperature at the transition midpoint is as follows: La-LA-60 < La-OA-60 < α-La. La-OA-60 complex inhibited tubulin polymerization in vitro. Although the structures of La-OA-60 and La-LA-60 were different, these two complexes had similar cytotoxic effect to DU145 human prostate cancer cells. Samples of La-OA-60 that have been renatured after denaturation lost the specific biological activity toward tumor cells.  相似文献   
35.

Background

Accelerometers, initially waist-worn but increasingly wrist-worn, are used to assess physical activity free from reporting-bias. However, its acceptability by study participants is unclear. Our objective is to assess factors associated with non-consent to a wrist-mounted accelerometer in older adults.

Methods

Data are from 4880 Whitehall II study participants (1328 women, age range = 60–83), requested to wear a wrist-worn accelerometer 24 h every day for 9 days in 2012/13. Sociodemographic, behavioral, and health-related factors were assessed by questionnaire and weight, height, blood pressure, cognitive and motor function were measured during a clinical examination.

Results

210 participants had contraindications and 388 (8.3%) of the remaining 4670 participants did not consent. Women, participants reporting less physical activity and less favorable general health were more likely not to consent. Among the clinical measures, cognitive impairment (Odds Ratio = 2.21, 95% confidence interval: 1.22–4.00) and slow walking speed (Odds Ratio = 1.38, 95% confidence interval: 1.02–1.86) were associated with higher odds of non-consent.

Conclusions

The rate of non-consent in our study of older adults was low. However, key markers of poor health at older ages were associated with non-consent, suggesting some selection bias in the accelerometer data.  相似文献   
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In vitro terminal differentiation in a female myeloid leukaemia cell line (HL-60) was induced by either of the two inducing agents, dimethylsulphoxide (DMSO) and dimethylformamide (DMF). A higher frequency of more mature myeloid cells was noted with increasing concentrations of the inducing agents up to the optimal dose limits for cell viability, and with longer post-induction incubation periods. The highest percentage of polymorphs was obtained at 8 days post-induction with 1.25% DMSO and after 6 and 8 days exposure to 90 mM DMF. A proportion of polymorphs showed non-sex specific drumstick-like nuclear appendages, which were morphologically similar to the sex-specific drumsticks found in polymorphs from normal females in vivo. The correlation between the nuclear lobe counts and the frequencies of drumstick-like appendages in polymorphs was also similar to that reported for drumsticks in blood cells in vivo. The various stages of terminal differentiation and nuclear appendage formation in polymorphs under induced differentiation were similar to those occurring in vivo. Chromosomal analyses of this cell line indicated that individual cells had lost one X chromosome, and no portion of the missing X was detected in any of the rearranged chromosomes. Since no truly sex-specific drumsticks appeared to be present in the polymorphs of this cell line containing only one X chromosome, the study supports the accepted notion that there is a correlation between drumstick frequency and the presence of one versus two X chromosomes.  相似文献   
37.
An alternative method to other technologies to clean up the soil, air and water pollution by heavy metals is phytoremediation. Therefore, a pot culture experiment was conducted at the College of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran, in 2014 to determine the potential absorption of cadmium by Portulaca oleracea (Common purslane), Solanum nigrum (Black nightshade), Abutilon theophrasti (Velvetleaf) and Taraxacum officinale (Dandelion). The type of experiment was completely randomized design with factorial arrangement and four replications. The soil in pot was treated with different rates of CdCl2.H2O (0 (control), 10, 20, 40, 60, and 80 mg Cd/kg soil) and the plants were sown. With increasing concentration levels, fresh weight and dry weight of shoots and roots of all plant species were reduced. The reduction severity was ranked according the following order, P. oleracea > A. theophrasti > S. nigrum > T. officinale. Bioconcentration factor (BCF), Translocation factor (TF) and Translocation efficiency (TE%) was ranked according the following order, T. officinale > S. nigrum > A. theophrasti > P. oleracea. The results of this study revealed that T. officinale and S. nigrum are effective species to phytoremediate Cd-contaminated soil.  相似文献   
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Background

The objective of this study is to determine the effect of a consultation model, Beliefs, Attitudes, Subjective Norms and Enabling Factors (BASNEF), and the counselling steps using GATHER-Greet clients, Ask clients about themselves, Tell clients about their choices, Help clients choose, Explain what to do, and Return for follow-up-on the continuation rates of exclusive breastfeeding in mothers of premature infants.

Methods

This is a randomized controlled clinical trial carried out on 124 mothers with premature infants hospitalized in Fatemieh Hospital, city of Hamadan, in 2014. Participants were randomly assigned to either the intervention or control groups. The initial demographic questionnaire carried out in both groups included three questions about the continuation of exclusive breastfeeding, BASNEF, a checklist related to the lactation performance documented by mothers and the weight gain of their infants. Five breastfeeding consultation sessions based on the BASNEF model and counselling steps using GATHER, were held for the mothers in the intervention group for five consecutive days. Then follow-up weight gain and the questionnaire completion were performed in both groups at 1, 2, 3 and 4 months after the intervention.

Results

Baseline characteristics were similar in the two groups. There were no significant differences between both groups in the rate of exclusive breastfeeding, lactation performance and infant weight at baseline. The intervention group had significantly higher rates of exclusive breastfeeding, 72.6% versus the control group of 16.1%, at the end of the 4 month follow-up. Also the intervention group had significantly higher mean scores of lactation performance (8.62?±?2.08 vs 6.40?±?1.84 in the control group) and infant weight (5694.80?±?779.43 vs 4760.17?±?859.12 in the control group) at the end of the 4 month follow-up.

Conclusion

Breastfeeding consultation of mothers based on the BASNEF model and using GATHER counselling steps increased the rate of exclusive breastfeeding, lactation performance and weight gain of premature infants. Therefore, breastfeeding counselling sessions are recommended for all mothers of premature infants.

Trial registration

Iranian Registry of Clinical Trials number IRCT2014111013405N6 and date registered, January 5, 2015.
  相似文献   
40.
High molecular weight DNA from fixed cytogenetic preparations.   总被引:2,自引:0,他引:2       下载免费PDF全文
Cell pellets that have been stored in routine clinical cytogenetic fixative were studied for the presence of intact DNA. A method for the isolation of high molecular weight DNA from fixed cytogenetic preparations of human leukocytes, bone marrow, and cell hybrid cultures is presented. DNA preparations from fixed pellets were cleaved with restriction enzymes, transferred to nitrocellulose filters after agarose gel electrophoresis, and hybridized to radiolabeled probes to demonstrate that fixed cell pellets could yield DNA of sufficient quality for Southern blot hybridization analysis. This protocol may be useful for molecular analysis of DNA from fixed cell pellets of patients who are unavailable for additional sampling.  相似文献   
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