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101.
BackgroundLong‐term follow‐up is necessary to understand the impact of perinatal interventions. Exploring parents'' motives and experiences in consenting to their children taking part in longitudinal studies and understanding what outcomes are important to families may enhance participation and mitigate the loss to follow‐up. As existing evidence is largely based on investigators'' perspectives using Western samples, the present pilot study explored parents'' perspectives in a multicultural New Zealand context.MethodsData were generated using semi‐structured interviews with parents whose children had participated in a longitudinal study after neonatal recruitment. Parents'' experiences of being part of the study were analysed thematically using an inductive approach.ResultsParents (n = 16) were generally happy with the outcomes measured. Additionally, parents were interested in lifelong goals such as the impact of parental diabetes. We identified three themes: (1) Facilitators: Research participation was aided by motives and parent and research characteristics such as wishing to help others and straightforward recruitment; (2) Barriers: A hesitancy to participate was due to technical and clinical research aspects, participation burden and cultural barriers, such as complex wording, time commitment and nonindigenous research and (3) Benefits: Children and parents experienced advantages such as the opportunity for education.ConclusionsParents reported positive experiences and described the unexpected benefit of increasing families'' health knowledge through participation. Improvements for current follow‐up studies were identified. Different ethnicities reported different experiences and perspectives, which warrants ongoing research, particularly with indigenous research participants.Patient or Public ContributionNo active partnership with parents of patients took place.  相似文献   
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Background

Extracted from the traditional Chinese medicine of Kushen, matrine is an alkaloid with potential anti-neoplastic and anti-inflammatory effects. Here, we examined the effect of matrine on proliferation and apoptosis of cultured retinoblastoma cells.

Methods

The retinoblastoma cell lines Y79, WERI-RB1 and SO-RB50 were treated with matrine in increasing concentrations from 0.2-1.1?mg/ml for 24?hours, and the cell proliferation rate was measured. The cells were exposed to matrine at 50% inhibition concentration (IC50) for 12, 24 and 48?hours. Cell cycle was analyzed by flow cytometry, concentration of proteins regulating cell cycle and apoptosis was determined by Western blot, apoptosis rate was measured by TUNEL staining, and cell morphology was assessed by electron transmission microscopy.

Results

The retinoblastoma cell lines Y79, WERI-RB1 and SO-RB50 showed an increased inhibition of cell proliferation with increasing matrine concentrations. Applying the IC50 concentration of matrine, the alteration of the cell cycle, including a reduced percentage of the S phase, was significantly (P?<?0.01) associated with a longer treatment time by matrine. Correspondingly, the cell-cycle-associated proteins P21 and P27 were up-regulated and the protein cyclinD1 was down-regulated. The apoptosis-associated protein Bcl-2 was down-regulated, and Bax was up-regulated. In a similar manner, the apoptosis rate was significantly increased with longer treatment time.

Conclusions

Matrine added to cultures of immortalized retinoblastoma cells led to a reduced tumor cell proliferation, decreased rate of mitosis and an increased tumor cell apoptosis, paralleled by corresponding changes in the proteins regulating the cell cycle or apoptosis.  相似文献   
105.
SignificanceLine-field confocal optical coherence tomography (LC-OCT) is a recently introduced high-resolution imaging modality based on a combination of low-coherence optical interferometry and reflectance confocal optical microscopy with line illumination and line detection. Capable of producing three-dimensional (3D) images of the skin with cellular resolution, in vivo, LC-OCT has been mainly applied in dermatology and dermo-cosmetology. The LC-OCT devices capable of acquiring 3D images reported so far are based on a Linnik interferometer using two identical microscope objectives. In this configuration, LC-OCT cannot be designed to be a very compact and light device, and the image acquisition speed is limited.AimThe objective of this work was to develop a more compact and lighter LC-OCT device that is capable of acquiring images faster without significant degradation of the resolution and with optimized detection sensitivity.ApproachWe developed an LC-OCT device based on a Mirau interferometer using a single objective. Dynamic adjustment of the camera frequency during the depth scan is implemented, using a faster camera and a more powerful light source. The reflectivity of the beam-splitter in the Mirau interferometer was optimized to maximize the detection sensitivity. A galvanometer scanner was incorporated into the device for scanning the illumination line laterally. A stack of adjacent B-scans, constituting a 3D image, can thus be acquired.ResultsThe device is able to acquire and display B-scans at 17 fps. 3D images with a quasi-isotropic resolution of 1.5  μm (1.3, 1.9, and 1.1  μm in the x,y, and z directions, respectively) over a field of 940  μm×600  μm×350  μm (x×y×z) can be obtained. 3D imaging of human skin at cellular resolution, in vivo, is reported.ConclusionsThe acquisition rate of the B-scans, at 17 fps, is unprecedented in LC-OCT. Compared with the conventional LC-OCT devices based on a Linnik interferometer, the reported Mirau-based LC-OCT device can acquire B-scans 2 times faster. With potential advantages in terms of compactness and weight, a Mirau-based device could easily be integrated into a smaller and lighter handheld probe for use by dermatologists in their daily medical practice.  相似文献   
106.
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   
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108.
Eyes with normal pressure glaucoma and eyes with high pressure glaucoma show a similar optic disc appearance with marked differences to eyes with vascular optic neuropathy. Non-vascular, potentially barotraumatic factors in addition to intraocular pressure (IOP) may thus play a role in glaucoma. Recent studies have shown that cerebrospinal fluid pressure (CSFP), arterial blood pressure and IOP are correlated with each other, higher CSFP is associated with younger age, higher blood pressure and higher body mass index, some patients with normal (IOP) pressure glaucoma have abnormally low CSFP and thus an abnormally high trans-lamina cribrosa pressure difference and a small orbital CSF space, the orbital CSF space width is associated with CSFP and the estimated CSFP correlated better with open-angle glaucoma-related parameters than IOP. The orbital CSFP as counter-pressure against IOP may play a role in the pathogenesis of glaucoma.  相似文献   
109.
People appear to vary in their susceptibility to lifestyle risk factors for cardiometabolic disease; determining a priori who is most sensitive may help optimize the timing, design, and delivery of preventative interventions. We aimed to ascertain a person’s degree of resilience or sensitivity to adverse lifestyle exposures and determine whether these classifications help predict cardiometabolic disease later in life; we pooled data from two population-based Swedish prospective cohort studies (n = 53,507), and we contrasted an individual’s cardiometabolic biomarker profile with the profile predicted for them given their lifestyle exposure characteristics using a quantile random forest approach. People who were classed as ‘sensitive’ to hypertension- and dyslipidemia-related lifestyle exposures were at higher risk of developing cardiovascular disease (CVD, hazards ratio 1.6 (95% CI: 1.3, 1.91)), compared with the general population. No differences were observed for type 2 diabetes (T2D) risk. Here, we report a novel approach to identify individuals who are especially sensitive to adverse lifestyle exposures and who are at higher risk of subsequent cardiovascular events. Early preventive interventions may be needed in this subgroup.  相似文献   
110.
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