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1.
Ilona Merikanto Outi Saarenpää-Heikkilä Tiina Paunio Timo Partonen 《Chronobiology international》2017,34(5):650-658
Sleep problems during pregnancy impair maternal health and increase the risk for adverse pregnancy outcome. The circadian preference toward eveningness has been associated with sleep problems in previous studies. Here, we studied whether evening-type women had more sleep problems during their pregnancy, as compared with other chronotypes, in a sample consisting of 1653 pregnant women from the Finnish CHILD-SLEEP Birth Cohort. Chronotype was assessed with a shortened version of the morningness–eveningness questionnaire. Pregnant evening-type women reported more sleep problems, including troubles of falling asleep (OR = 3.4, p < 0.0001), poor sleep quality (OR = 2.9, p < 0.01) and daily tiredness (OR = 3.2, p < 0.0001) than the morning-type women, even after controlling for sleep duration and sleep deprivation. They had higher scores on Epworth Sleepiness Scale (p < 0.05), Basic Nordic Sleep Questionnaire (p < 0.0001) and Global Seasonality Score (p < 0.01) and were also more often smokers, also during pregnancy (p < 0.001) and reported poorer general health (p < 0.001) than the morning-type women. They also reported having had more sleep problems during their childhood (OR = 1.5, p < 0.05) and adolescence (OR = 2.0, p < 0.001) than the morning-type women. Our results indicate that eveningness is associated with more sleep problems and unhealthy life habits during pregnancy. 相似文献
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Mindaugas Tamoinas Emilija V. Plorina Marta Lange Aleksandrs Derjabo Ilona Kuzmina Dmitrijs Bizuks Janis Spigulis 《Journal of biophotonics》2020,13(3)
This clinical study is a first attempt to use autofluorescence for recurrence diagnosis of skin cancer in postoperative scars. The proposed diagnostic parameter is based on a reduction in scar autofluorescence, evaluated in the green spectral channel. The validity of the method has been tested on 110 postoperative scars from 56 patients suspected of non‐melanoma skin cancer, with eight patients (13 scars) available for the repeated examination. The recurrence diagnosis within a scar has been made after two subsequent autofluorescence check‐ups, representing the temporal difference between the scar autofluorescence amplitudes as a vector. The recognition of recurrence has been discussed to represent the significant deviations from the value of vector angle θ. This new autofluorescence‐based method can be easily integrated into the postoperative monitoring of surgical scars and can help diagnose the recurrence of skin cancer from the early stage of scar development. 相似文献
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By use of ion exchange chromatography we have isolated two discrete classes of “free” glycosaminoglycans (GAG) from human plasma. The GAG fractions were tested for their effects on two lipoprotein lipase (LPL) enzyme systems containing an apolipo-protein C-II activated emulsion as the triglyceride substrate and bovine serum albumin as the free fatty acid acceptor. The low-charge GAG (Fraction I) had essentially no effect on the LPL reaction. The high-charge GAG (Fraction II) stimulated the LPL reaction 100 to 300%. The GAG composition of each fraction was investigated with chemical and enzymatic techniques. Fraction I consisted of low-charge chondroitin sulfate noncovalently bound to protein. Fraction II consisted of a mixture of high-charge GAG non-covalently bound to protein. Degradation with nitrous acid eliminated the ability of high-charge GAG to stimulate LPL. This and other evidence suggests that the high-charge GAG in human plasma responsible for LPL activation is heparan sulfate (HS). We suggest that plasma HS may modulate triglyceride clearance mechanisms by its interaction with LPL. 相似文献
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Ilona Schonn Jana Hennesen Dorothee C. Dartsch 《Apoptosis : an international journal on programmed cell death》2010,15(2):162-172
The topoisomerase IIα inhibitor etoposide is a ‘broad spectrum’ anticancer agent and a potent inducer of DNA double strand
breaks. DNA damage response of mammalian cells usually involves cell cycle arrest and DNA repair or, if unsuccessful, cell
death. We investigated these processes in the human colon cancer cell line HT-29 treated with three different etoposide regimens
mimicking clinically relevant plasma concentrations of cancer patients. Each involved a period of drug-free incubation following
etoposide exposure to imitate the decline of plasma levels between the cycles of chemotherapy. We found a massive induction
of double strand breaks that were rapidly and nearly completely fixed long before the majority of cells underwent apoptosis
or necrosis. An even greater percentage of cells lost clonogenicity. The occurrence of double strand breaks was accompanied
by a decrease in the levels of Ku70, Ku86 and DNA-PKcs as well as an increase in the level of Rad51 protein. Twenty-four hours after the first contact with etoposide we found a
pronounced G2/M arrest, regardless of the duration of drug exposure, the level of double strand breaks and the extent of their repair.
During the subsequent drug-free incubation period, the loss of clonogenicity correlated well with the preceding G2/M arrest as well as with the amount of cell death found several days after exposure. However, it correlated neither with
early apoptosis or necrosis nor with any of the other investigated parameters. These results suggest that the G2/M arrest is an important determinant in the cytostatic action of etoposide and that the removal of DNA double strand breaks
is not sufficient to ensure cell survival. 相似文献
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