Determinants of cancer screenings participation in Queensland: a scoping review.

Introduction Cancer screening programmes for cervical, breast, and colorectal cancer have successfully reduced mortality rates among target groups. However, a large proportion of women and men are unscreened. Aim This review aims to provide an overview of the literature regarding the determinants of cancer screening participation among target groups in Queensland. Methods Electronic databases were searched for studies on determinants of cancer screening participation in Queensland. Retrieved studies were screened, and eligible articles were selected for data extraction. Both peer-reviewed and grey literature studies were included. The determinants of cancer screening participation were classified according to the I-Change model. Results Sixteen out of 75 articles were selected and analysed. Information factors, such as the lack of tailored strategies, determined cancer screening participation. Age, gender, cultural beliefs, fear and past experiences were the most reported predisposing factors to cancer screening participation. Lack of knowledge, misconceptions, low awareness, timely access to service, privacy and confidentiality were mainly reported awareness and motivation factors. Encouragement from health professionals, providing more information and interactions with communities would result in different effects on cancer screening participation among the target groups. Discussion The I-Change model is a valuable tool in mapping the current determinants of cancer screening participation programs. Further research may be needed to fully understand the barriers and facilitators of cancer screening programs.

Three-dimensional refractive index estimation based on deep-inverse non-interferometric optical diffraction tomography (ODT-Deep).

Optical diffraction tomography (ODT) solves an inverse scattering problem to obtain label-free, 3D refractive index (RI) estimation of biological specimens. This work demonstrates 3D RI retrieval methods suitable for partially-coherent ODT systems supported by intensity-only measurements consisting of axial and angular illumination scanning. This framework allows for access to 3D quantitative RI contrast using a simplified non-interferometric technique. We consider a traditional iterative tomographic solver based on a multiple in-plane representation of the optical scattering process and gradient descent optimization adapted for focus-scanning systems, as well as an approach that relies solely on 3D convolutional neural networks (CNNs) to invert the scattering process. The approaches are validated using simulations of the 3D scattering potential for weak phase 3D biological samples.

Digital Holographic Microscopy to Assess Cell Behavior.

Digital holographic microscopy is an imaging technique particularly well suited to the study of living cells in culture, as no labeling is required and computed phase maps produce high contrast, quantitative pixel information. A full experiment involves instrument calibration, cell culture quality checks, selection and setup of imaging chambers, a sampling plan, image acquisition, phase and amplitude map reconstruction, and parameter map post-processing to extract information about cell morphology and/or motility. Each step is described below, focusing on results from imaging four human cell lines. Several post-processing approaches are detailed, with an aim of tracking individual cells and dynamics of cell populations.

Dual-modality digital holographic and polarization microscope to quantify phase and birefringence signals in biospecimens with a complex microstructure.

Optical phase and birefringence signals occur in cells and thin, semi-transparent biomaterials. A dual-modality quantitative phase and polarization microscope was designed to study the interaction of cells with extracellular matrix networks and to relate optical pathlength and birefringence signals within structurally anisotropic biomaterial constructs. The design was based on an existing, custom-built digital holographic microscope, to which was added a polarization microscope utilizing liquid crystal variable retarders. Phase and birefringence channels were calibrated, and data was acquired sequentially from cell-seeded collagen hydrogels and electrofabricated chitosan membranes. Computed phase height and retardance from standard targets were accurate within 99.7% and 99.8%, respectively. Phase height and retardance channel background standard deviations were 35 nm and 0.6 nm, respectively. Human fibroblasts, visible in the phase channel, aligned with collagen network microstructure, with retardance and azimuth visible in the polarization channel. Electrofabricated chitosan membranes formed in 40 µm tall microfluidic channels possessed optical retardance ranging from 7 to 11 nm, and phase height from 37 to 39 µm. These results demonstrate co-registered dual-channel acquisition of phase and birefringence parameter maps from microstructurally-complex biospecimens using a novel imaging system combining digital holographic microscopy with voltage-controlled polarization microscopy.

Computational multi-wavelength phase synthesis using convolutional neural networks [Invited].

Multi-wavelength digital holographic microscopy (MWDHM) provides indirect measurements of the refractive index for non-dispersive samples. Successive-shot MWDHM is not appropriate for dynamic samples and single-shot MWDHM significantly increases the complexity of the optical setup due to the need for multiple lasers or a wavelength tunable source. Here we consider deep learning convolutional neural networks for computational phase synthesis to obtain high-speed simultaneous phase estimates on different wavelengths and thus single-shot estimates of the integral refractive index without increased experimental complexity. This novel, to the best of our knowledge, computational concept is validated using cell phantoms consisting of internal refractive index variations representing cytoplasm and membrane-bound organelles, respectively, and a simulation of a realistic holographic recording process. Specifically, in this work we employed data-driven computational techniques to perform accurate dual-wavelength hologram synthesis (hologram-to-hologram prediction), dual-wavelength phase synthesis (unwrapped phase-to-phase prediction), direct phase-to-index prediction using a single wavelength, hologram-to-phase prediction, and 2D phase unwrapping with sharp discontinuities (wrapped-to-unwrapped phase prediction).

Simulation of digital holographic recording and reconstruction using a generalized matrix method.

In recent years, research efforts in the field of digital holography have expanded significantly, due to the ability to obtain high-resolution intensity and phase images. The information contained in these images have become of great interest to the machine learning community, with applications spanning a wide portfolio of research areas, including bioengineering. In this work, we seek to demonstrate a high-fidelity simulation of holographic recording. By accurately and numerically simulating the propagation of a coherent light source through a series of optical elements and the object itself, we accurately predict the optical interference of the object and reference wave at the recording plane, including diffraction effects, aberrations, and speckle. We show that the optical transformation that predicts the complex field at the recording plane can be generalized for arbitrary holographic recording configurations using a matrix method. In addition, we provide a detailed description of digital phase reconstruction and aberration compensation for a variety of off-axis holographic configurations. Reconstruction errors are presented for the various holographic recording geometries and complex field objects. While the primary objective of this work is not to evaluate phase reconstruction approaches, the reconstruction of simulated holograms provides validation of the generalized simulation method. The long-term goal of this work is that the generalized holographic simulation motivates the use of phase reconstruction of the simulated holograms to populate databases for training machine-learning algorithms aimed at classifying relevant objects recorded through a variety of holographic setups.

Keratin 19 maintains E-cadherin localization at the cell surface and stabilizes cell-cell adhesion of MCF7 cells.

A cytoskeletal protein keratin 19 (K19) is highly expressed in breast cancer but its effects on breast cancer cell mechanics are unclear. In MCF7 cells where K19 expression is ablated,we found that K19 is required to maintain rounded epithelial-like shape and tight cell-cell adhesion. A loss of K19 also lowered cell surface E-cadherin levels. Inhibiting internalization restored cell-cell adhesion of KRT19  knockout cells, suggesting that E-cadherin internalization contributed to defective adhesion. Ultimately, while K19 inhibited cell migration and invasion, it was required for cells to form colonies in suspension. Our results suggest that K19 stabilizes E-cadherin complexes at the cell membrane to maintain cell-cell adhesion which inhibits cell invasiveness but provides growth and survival advantages for circulating tumor cells.

Optimizing Active Tuberculosis Case Finding: Evaluating the Impact of Community Referral for Chest X-ray Screening and Xpert Testing on Case Notifications in Two Cities in Viet Nam.

To accelerate the reduction in tuberculosis (TB) incidence, it is necessary to optimize the use of innovative tools and approaches available within a local context. This study evaluated the use of an existing network of community health workers (CHW) for active case finding, in combination with mobile chest X-ray (CXR) screening events and the expansion of Xpert MTB/RIF testing eligibility, in order to reach people with TB who had been missed by the current system. A controlled intervention study was conducted from January 2018 to March 2019 in five intervention and four control districts of two low to medium TB burden cities in Viet Nam. CHWs screened and referred eligible persons for CXR to TB care facilities or mobile screening events in the community. The initial diagnostic test was Xpert MTB/RIF for persons with parenchymal abnormalities suggestive of TB on CXR or otherwise on smear microscopy. We analyzed the TB care cascade by calculating the yield and number needed to screen (NNS), estimated the impact on TB notifications and conducted a pre-/postintervention comparison of TB notification rates using controlled, interrupted time series (ITS) analyses. We screened 30,336 individuals in both cities to detect and treat 243 individuals with TB, 88.9% of whom completed treatment successfully. All forms of TB notifications rose by +18.3% (95% CI: +15.8%, +20.8%). The ITS detected a significant postintervention step-increase in the intervention area for all-form TB notification rates (IRR(ß6) = 1.221 (95% CI: 1.011, 1.475); p = 0.038). The combined use of CHWs for active case findings and mobile CXR screening expanded the access to and uptake of Xpert MTB/RIF testing and resulted in a significant increase in TB notifications. This model could serve as a blueprint for expansion throughout Vietnam. Moreover, the results demonstrate the need to optimize the use of the best available tools and approaches in order to end TB.

Machine Learning with Optical Phase Signatures for Phenotypic Profiling of Cell Lines.

Robust and reproducible profiling of cell lines is essential for phenotypic screening assays. The goals of this study were to determine robust and reproducible optical phase signatures of cell lines for classification with machine learning and to correlate optical phase parameters to motile behavior. Digital holographic microscopy (DHM) reconstructed phase maps of cells from two pairs of cancer and non-cancer cell lines. Seventeen image parameters were extracted from each cell's phase map, used for linear support vector machine learning, and correlated to scratch wound closure and Boyden chamber chemotaxis. The classification accuracy was between 90% and 100% for the six pairwise cell line comparisons. Several phase parameters correlated with wound closure rate and chemotaxis across the four cell lines. The level of cell confluence in culture affected phase parameters in all cell lines tested. Results indicate that optical phase features of cell lines are a robust set of quantitative data of potential utility for phenotypic screening and prediction of motile behavior. © 2019 International Society for Advancement of Cytometry.

Application of manures to mitigate the harmful effects of electrokinetic remediation of heavy metals on soil microbial properties in polluted soils.

Ethylenediaminetetraacetic acid (EDTA) used with electrokinetic (EK) to remediate heavy metal-polluted soils is a toxic chelate for soil microorganisms. Therefore, this study aimed to evaluate the effects of alternative organic chelates to EDTA on improving the microbial properties of a heavy metal-polluted soil subjected to EK. Cow manure extract (CME), poultry manure extract (PME) and EDTA were applied to a lead (Pb) and zinc (Zn)-polluted calcareous soil which were subjected to two electric intensities (1.1 and 3.3 v/cm). Soil carbon pools, microbial activity, microbial abundance (e.g., fungal, actinomycetes and bacterial abundances) and diethylenetriaminepentaacetic acid (DTPA)-extractable Pb and Zn (available forms) were assessed in both cathodic and anodic soils. Applying the EK to soil decreased all the microbial variables in the cathodic and anodic soils in the absence or presence of chelates. Both CME and PME applied with two electric intensities decreased the negative effect of EK on soil microbial variables. The lowest values of soil microbial variables were observed when EK was combined with EDTA. The following order was observed in values of soil microbial variables after treating with EK and chelates: EK + CME or EK + PME > EK > EK + EDTA. The CME and PME could increase the concentrations of available Pb and Zn, although the increase was less than that of EDTA. Overall, despite increasing soil available Pb and Zn, the combination of EK with manures (CME or PME) mitigated the negative effects of using EK on soil microbial properties. This study suggested that the synthetic chelates such as EDTA could be replaced with manures to alleviate the environmental risks of EK application.

[Attenuated nodal response. Apropos of 30 cases]. / La résponse nodale atténuée. A propos de 30 cas.

In a population of 600 consecutive patients undergoing endocavitary electrophysiological study to assess nodal conduction, 40 had an atriohisian Wenckenbach point of over 200/mn. In 30 cases, vagal stimulation with ATP (10 to 40 mg IV) provoked an increase in atrioventricular conduction, with lengthening the AH interval by over 100 p. 100 or transient atrioventricular block. This increase allowed elimination of an accessory atriohisian pathway which could give similar high Wenckenbach points, but which do not show decremental conduction. In all our cases, the conduction passed through the artrioventricular node (AVN) whose response to rapid atrial stimulation was attenuated compared to normal. The parameter of this attenuated nodal response varied from case to case, but in general, the intervals were shorter than normal. The AH interval was less than 50 ms in 22 cases (N = 70 +/- 20 ms). The effective nodal refractory period was shorter than the functional atrial refractory period in 20 cases. The shortest atrial cycles transmitted 1/1 to the ventricles ranged from 230 to 300 ms (274 +/- 33 ms) (N = 375 +/- 40 ms). The functional structure of the AVN was studied by the lengthening of the AH interval with heart rate : 5 types were distinguished : 10 patients had progressive lengthening of AH interval greater than 100 ms (Type I) as in a normal AVN; 5 had progressive lengthening of AH interval of less than 50 ms (Type II), 5 had progressive lengthening of AH which then remained stable for a number of heart rates before lengthening again (Type III); 3 had an initial moderate lengthening of the AH interval which then became more rapid (Type IV) and 7 had no change in AH until 120/mn and then a progressive lengthening was observed (Type V). Two functional groups could also be identified depending on whether the lengthening was progressive, suggesting a single nodal pathway (Types I and II) or on whether differing increases were observed related to the atrial rate, suggesting two (Types IV and V) or even three (Type III) atrionodal or intranodal pathways with different refractory periods. Of these 30 patients, only 14 had documented supraventricular tachycardia, 13 being atrial fibrillation and the other a junctional tachycardia. Attenuated nodal behavior does not seem to be a direct cause of supraventricular arrhythmias but these arrhythmias were not tolerated as well because of the special properties of the atrioventricular node.

[Electrocardiography of delayed potentials in post-excitation syndrome]. / Electrocardiographie des potentiels tardifs du syndrome de post-excitation.

Electrophysiological investigation and pericardial mapping have succeeded in isolating a particular type of ventricular tachycardia occurring in young subjects with no coronary artery disease who have dysplasia of the right ventricle. When these patients are no longer controlled by medical treatment, they may benefit from surgery. This condition is characterised by the presence of delayed potentials which appear after the end of ventricular depolarisation as recorded by épicardial mapping. This post-excitation phenomenom may also be demonstrated either by an intracavitary electrode or sometimes on an amplified ECG. This study describes a new method using the techniques of signal averaging and summation technique to demonstrate the delayed potential in the post-excitation syndrome. It is non-invasive, and seems to give better results than those obtained from intracavitary exploration.

[Applications of a minicomputer in an electrocadiography department]. / Applications d'un mini-ordinateur dans un département d'électrocardiologie

The wide potential of minicomputers and their versatility have modified the traditional image of the computer, allowing it to gain a real foothold in a cardiological service. Examples of some original programmes are: the automatic assessment of a pacemaker on the test bench, the formation of programmed impulses for electrocardiographic investigation, the analysis of arrhythmias by a histogram of the RR interval of frequency analysis, the recording of isochrones in pericardial cartography.

[Threshold in surveillance of pacemaker wearers]. / Le seuil dans la surveillance des porteurs de pacemakers

Measurement of the threshold is important in the follow-up of pacemaker patients; it permits the assessment of the safety margin, between, on the one hand, the electrical impulse, and, on the other, the possible output of the pacemaker. In fact, one can only rarely obtain relative threshold measurements in the clinical situation using non-invasive techniques; this ability is limited to some units made only by a few pacemaker manufacturers. A decrease in the margin of safety may result from two main causes: an increase in the absolute threshold or a decrease in the pacemaker pulse amplitude due to depletion of the cells, or to electronic failure. If safety margin is reduced, and operative procedure is required to achieve the correct diagnosis by precise measurements of the absolute threshold.