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81.
BackgroundRisk-adjusted cancer screening and prevention is a promising and continuously emerging option for improving cancer prevention. It is driven by increasing knowledge of risk factors and the ability to determine them for individual risk prediction. However, there is a knowledge gap between evidence of increased risk and evidence of the effectiveness and efficiency of clinical preventive interventions based on increased risk. This gap is, in particular, aggravated by the extensive availability of genetic risk factor diagnostics, since the question of appropriate preventive measures immediately arises when an increased risk is identified. However, collecting proof of effective preventive measures, ideally by prospective randomized preventive studies, typically requires very long periods of time, while the knowledge about an increased risk immediately creates a high demand for action.SummaryTherefore, we propose a risk-adjusted prevention concept that is based on the best current evidence making needed and appropriate preventive measures available, and which is constantly evaluated through outcome evaluation, and continuously improved based on these results. We further discuss the structural and procedural requirements as well as legal and socioeconomical aspects relevant for the implementation of this concept.  相似文献   
82.
Anelloviruses (AVs) are found in the vast majority of the human population and are most probably part of a healthy virome. These viruses infect humans in the early stage of life, however, the characteristics of the first colonizing AVs are still unknown. We screened a collection of 107 blood samples from children between 0.4 and 64.8 months of age for the presence of three AV genera: the Alpha-, Beta- and Gammatorquevirus. The youngest child that was positive for AV was 1.2 months old, and a peak in prevalence (100% of samples positive) was reached between the twelfth and eighteenth months of life. Intriguingly, the beta- and gammatorqueviruses were detected most at the early stage of life (up to 12 months), whereas alphatorqueviruses, the most common AVs in adults, increased in prevalence in children older than 12 months. To determine whether that order of colonization may be related to oral transmission and unequal presence of AV genera in breast milk, we examined 63 breast milk samples. Thirty-two percent of the breast milk samples were positive in a qPCR detecting beta- and gammatorqueviruses, while alphatorqueviruses were detected in 10% of the samples, and this difference was significant (p = 0.00654). In conclusion, we show that beta- and gammatorqueviruses colonize humans in the first months of life and that breastfeeding could play a role in AV transmission.  相似文献   
83.
Background: To investigate associations between psychological problems and the use of healthcare and informal care and total costs among head and neck cancer (HNC) patients. Method: Data were used of the NETherlands QUality of Life and Biomedical Cohort study. Anxiety and depression disorder (diagnostic interview), distress, symptoms of anxiety and depression (HADS), and fear of cancer recurrence (FCR) and cancer worry scale (CWS) were measured at baseline and at 12-month follow-up. Care use and costs (questionnaire) were measured at baseline, 3-, 6-, 12-, and 24-month follow-up. Associations between psychological problems and care use/costs were investigated using logistic and multiple regression analyses. Results: Data of 558 patients were used. Distress, symptoms of anxiety or depression, FCR, and/or anxiety disorder at baseline were significantly associated with higher use of primary care, supportive care, and/or informal care (odds ratios (ORs) between 1.55 and 4.76). Symptoms of anxiety, FCR, and/or depression disorder at 12-month follow-up were significantly associated with use of primary care, supportive care, and/or informal care (ORs between 1.74 and 6.42). Distress, symptoms of anxiety, and FCR at baseline were associated with higher total costs. Discussion: HNC patients with psychological problems make more use of healthcare and informal care and have higher costs. This is not the result of worse clinical outcomes.  相似文献   
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IntroductionPublic health measures enacted to reduce COVID-19 transmission have affected individuals'' lifestyles, mental health, and psychological well-being. To date, little is known how stay-at-home orders have influenced the eating behaviors, weight development, and alcohol consumption of quarantined persons. The CoCo-Fakt cohort study analyzed these parameters and their association with psychological distress and coping strategies.MethodsAn online survey was conducted of all persons who tested positive for SARS-CoV-2 (infected persons [IP]) between December 12, 2020, and January 6, 2021, as well as their close contacts (contact persons [CP]) registered by the public health department of Cologne. 8,075 of 33,699 individuals were included in the analysis. In addition to demographic data, psychological distress, and coping strategies, information on changes in body weight, eating, and drinking behaviors was collected.ResultsIP lost 1.2 ± 4.4 kg during the quarantine period, and CP gained 1.6 ± 4.1 kg. The reasons given by IP for weight change were mainly loss of taste and feeling sick, whereas CP were more likely than IP to eat out of boredom. Higher psychological burden and lower coping strategies were associated with both weight gain and loss. Of the 30.8% of participants who changed their alcohol consumption during the quarantine period, CP in particular drank more alcohol (IP 15.2%; CP 47.7%). Significantly less alcohol was consumed by individuals with higher coping scores.ConclusionIn this short but psychologically stressful period of stay-at-home orders, changes in eating and drinking behavior as well as weight development are evident, mainly in high-risk contacts. To avoid possible long-term sequelae, health authorities should take these findings into account during the quarantine period; in particular, general practitioners should consider these findings during follow-up.  相似文献   
86.
The target of any cryopreservation procedure should be to ensure high survival rates of living cells after thawing. Two important parameters determine the success of any cryopreservation protocol: the manner in which cells regain equilibrium in response to cooling, and the speed of freezing (cooling rate). Slow-rate freezing protocols result in the formation of ice crystals during cooling and warming. Vitrification, in which high cooling rates in combination with a high concentration of cryoprotectant are used, does not produce any ice crystals during cooling and warming. However, there is a practical limit to the attainable cooling speed, and also a biological limit to the concentration of cryoprotectant tolerated by the cells during vitrification. Although post-warming survival depends on the species, the developmental stage and the quality of the embryos being vitrified, it seems clear that vitrification methods are increasingly successful and might be a better method than slow cooling procedures in the field of cryobiology. Many of the potential problems and benefits underlying vitrification as a method of choice for embryo cryopreservation in clinical embryology will be discussed in this review.  相似文献   
87.
The world's oceans are polluted by a continuous inflow of plastic. Plastic fragments finally into microplastic, which can be taken up, for example by plankton, and subsequently by the entire ocean food web. An approach to reduce plastic pollution constitutes the accelerated microplastic degradation in marine environments. TiO2 (anatase) is commonly used as an oxidative photocatalyst and well known to catalyze the degradation of organic compounds upon UV irradiation.In this study, a selective activation of TiO2 (anatase) particles encapsulated by Ca- or Sr-polyphosphate is presented. The TiO2 polyphosphate core-shell particles are envisaged as additives in plastic products. The highly concentrated cations from seawater, viz. Na+ and Mg2+, displace the Ca2+ or Sr2+ cations from the polyphosphate shell. As a result, the polyphosphate coating dissolves and thus the photocatalytically active TiO2 core is released. The stability of the TiO2 polyphosphate particles in potable water and the seawater activated disintegration of methylene blue, methyl methacrylate, terephtalic acid, and poly(vinyl alcohol) was shown. It has been demonstrated, that the sweetwater stable polyphosphate coating degrades in the presence of seawater, which could be monitored by the activation of the TiO2 (anatase) photocatalyst.  相似文献   
88.

Introduction

Administration of cadmium (Cd) after 60 h (H) incubation induces ventral body wall defect (VBWD) similar to the omphalocele phenotype in the chick embryo. In this model, the earliest histological changes have been observed in somites commencing at 4-h post-treatment (4H). The molecular mechanism by which Cd acts in this critical period of embryogenesis still remains unclear. Sonic hedgehog (SHH) signalling plays an important role in vertebrate development, including somitogenesis and thus ventral body wall formation. Patched (PTCH), a cell membrane receptor for SHH, is expressed in somites and Patched knockout mice display somite dysfunction. Another transmembrane receptor, Smoothened (SMO), is also expressed in somites and transduces the SHH signal regulated by PTCH. We designed this study to test the hypothesis that SHH signalling is downregulated during the critical period of early embryogenesis in the Cd-induced omphalocele chick model.

Methods

After 60 h of incubation, chicks were exposed to either chick saline or 50 μL of 50 μM cadmium acetate and divided into two groups: control and Cd (n = 24 for each group). Chicks were harvested 1, 4, and 8 h post-treatment. Real-time RT-PCR was performed to evaluate the relative mRNA expression level of SHH, PTCH and SMO. Immunofluorescence confocal microscopy was then performed to evaluate protein expression/distribution of SHH, PTCH and SMO.

Results

The relative mRNA expression levels of SHH, PTCH and SMO were significantly downregulated in the Cd group compared to controls at 4H post treatment, whereas, there were no significant differences at the other time points. Immunohistochemistry revealed that the intensity of SHH, PTCH and SMO was markedly diminished at 4 h in Cd-treated embryos compared to controls.

Conclusion

Disturbance of the SHH signalling pathway as evidenced by SHH, PTCH and SMO downregulation during the narrow window of early embryogenesis may result in somite maldevelopment, contributing to the omphalocele phenotype in the Cd chick model.  相似文献   
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