Peripheral-blood cytopenia, an early indicator of inborn errors of immunity.

Inborn errors of immunity (IEI) are inherited monogenic disorders resulting in defective immune response. Non-infectious presentations are increasingly more apparent. Widely available, cost-effective early indicators are needed.

Hematological findings in adult patients with SARS CoV-2 infection at Tygerberg Hospital Cape Town South Africa.

Background: Coronavirus disease 2019 (COVID-19) is associated with hematological abnormalities of variable severity. The full blood count (FBC) and leukocyte differential count (DIFF) could facilitate the prediction of disease severity and outcome in COVID-19. This study aimed to assess the hematological parameters in early severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and their correlation with disease outcome.

Mendelian susceptibility to mycobacterial disease in tuberculosis-hyperendemic South Africa.

Background: Severe infections in the absence of secondary immunodeficiency can alert clinicians to single-gene inborn errors of immunity/primary immunodeficiency disorders (PIDDs). Mendelian susceptibility to mycobacterial disease (MSMD) is characterised by selective susceptibility to mycobacterial infections due to inborn errors in the interleukin 12-interferon gamma pathway. The South African (SA) burden of hyperendemic tuberculosis (TB) infection provides an interesting context for the study of MSMD.

Phenotypic and immune functional profiling of patients with suspected Mendelian Susceptibility to Mycobacterial Disease in South Africa.

Background: Mendelian Susceptibility to Mycobacterial Disease (MSMD) is a primary immunodeficiency (PID) characterised by a predisposition to infection by weakly-pathogenic mycobacteria. In countries with a high prevalence of tuberculosis (TB), individuals with MSMD are also prone to infections by Mycobacterium tuberculosis. Several MSMD-associated genes have been described, all resulting in a disruption of IL-12 and IFN-γ cytokine axis, which is essential for control of mycobacterial infections.

Clinical Utility of Whole Exome Sequencing and Targeted Panels for the Identification of Inborn Errors of Immunity in a Resource-Constrained Setting.

Primary immunodeficiency disorders (PIDs) are inborn errors of immunity (IEI) that cause immune system impairment. To date, more than 400 single-gene IEI have been well defined. The advent of next generation sequencing (NGS) technologies has improved clinical diagnosis and allowed for discovery of novel genes and variants associated with IEI.

Identification of a novel WAS mutation in a South African patient presenting with atypical Wiskott-Aldrich syndrome: a case report.

Background: The X-linked recessive primary immunodeficiency disease (PIDD) Wiskott-Aldrich syndrome (WAS) is identified by an extreme susceptibility to infections, eczema and thrombocytopenia with microplatelets. The syndrome, the result of mutations in the WAS gene which encodes the Wiskott-Aldrich protein (WASp), has wide clinical phenotype variation, ranging from classical WAS to X-linked thrombocytopaenia and X-linked neutropaenia. In many cases, the diagnosis of WAS in first affected males is delayed, because patients may not present with the classic signs and symptoms, which may intersect with other thrombocytopenia causes.

Leaf economics and plant hydraulics drive leaf : wood area ratios.

Biomass and area ratios between leaves, stems and roots regulate many physiological and ecological processes. The Huber value H (sapwood area/leaf area ratio) is central to plant water balance and drought responses. However, its coordination with key plant functional traits is poorly understood, and prevents developing trait-based prediction models.

Radiance based method for accurate determination of volume scattering parameters using GPU-accelerated Monte Carlo.

Volume scattering is an important effect in different fields, ranging from biology to lighting. Models for volume scattering usually rely on parameters that are estimated with inverse methods that iteratively fit simulations to experimental data. To obtain accurate estimates for these parameters, the scattered intensity distribution can be used in such fitting methods.

Thermoresponsive scattering coating for smart white LEDs.

White light emitting diode (LED) systems, capable of lowering the color temperature of emitted light on dimming, have been reported in the literature. These systems all use multiple color LEDs and complex control circuitry. Here we present a novel responsive lighting system based on a single white light emitting LED and a thermoresponsive scattering coating.

Ozone-initiated terpene reaction products in five European offices: replacement of a floor cleaning agent.

Cleaning agents often emit terpenes that react rapidly with ozone. These ozone-initiated reactions, which occur in the gas-phase and on surfaces, produce a host of gaseous and particulate oxygenated compounds with possible adverse health effects in the eyes and airways. Within the European Union (EU) project OFFICAIR, common ozone-initiated reaction products were measured before and after the replacement of the regular floor cleaning agent with a preselected low emitting floor cleaning agent in four offices located in four EU countries.

Phosphor-converted LED modeling using near-field chromatic luminance data.

A new method of creating a source model of a phosphor-converted white LED is demonstrated. It is based on a simple phosphor model, of which some key parameters have been obtained from measuring the near-field chromatic and luminance characteristics of a complete LED. The accuracy of the model is verified by measurements and simulations on an LED with a ball lens as primary optic.

Effect of gabapentin on pain after cardiac surgery: a randomised, double-blind, placebo-controlled trial.

This study evaluated whether perioperative administration of gabapentin in cardiac surgery patients could reduce postoperative opioid consumption, postoperative sleep or perceived quality of recovery. This randomised controlled trial assigned 60 patients undergoing cardiac surgery to receive 1200 mg of gabapentin or placebo two hours preoperatively, and then 600 mg of gabapentin or placebo twice a day for the next two postoperative days. Postoperative opioid use was measured by the amount of fentanyl used in the first 48 hours postoperatively.

Short period holographic structures for backlight display applications.

The use of holographic structures is promising for the realization of efficient systems in backlight applications for displays. By applying surface relief gratings on top of a side-lit lightguide we realize a backlight that avoids the use of color filters. The grating is used as a light outcoupling and color-separating element.

Polarized light out-coupling from lightguides for LCDs.

New designs of lightguide systems, which emit linear polarized light with a high efficiency for transmissive and transflective LCD applications, are presented. These systems are equipped with nano- and/or micro-structured films or coatings, which emit highly collimated or diffuse linearly polarized light with a high efficiency. The films are based on polarization-selective scattering, reflection, or diffraction of light and their properties can be tuned to a large extent dependent on their envisioned application.

Wire-grid diffraction gratings used as polarizing beam splitter for visible light and applied in liquid crystal on silicon.

The application of wire grid polarizers as efficient polarizing beam splitters for visible light is studied. The large differences between the transmissivity for different polarizations are explained qualitatively by using the theory of metallic wave guides. The results of rigorous calculations obtained by using the finite element method are compared with experiments for both classical and conical mount.

Polarized backlight based on selective total internal reflection at microgrooves.

A polarized backlight for LCD illumination is designed and fabricated in which s-polarized light is extracted owing to selective total internal reflection at microstructures in the anisotropic layer. From the measurement, the contrast ratio in normal viewing direction can be as high as 64. Luminous uniformity of higher than 80% is achieved for polarized backlights.

ATP augments von Willebrand factor-dependent shear-induced platelet aggregation through Ca2+-calmodulin and myosin light chain kinase activation.

Shear stress triggers von Willebrand factor (VWF) binding to platelet glycoprotein Ibalpha and subsequent integrin alpha(IIb)beta(3)-dependent platelet aggregation. Concomitantly, nucleotides are released from plateletdense granules, and ADP is known to contribute to shear-induced platelet aggregation (SIPA). We found that the impaired SIPA of platelets from a Hermansky-Pudlak patient lacking dense granules was restored by exogenous l-beta,gamma-methylene ATP, a stable P2X(1) agonist, as well as by ADP, confirming that in addition to ADP (via P2Y(1) and P2Y(12)), ATP (via P2X(1)) also contributes to SIPA.

P2X1-mediated ERK2 activation amplifies the collagen-induced platelet secretion by enhancing myosin light chain kinase activation.

The ATP-gated P2X1 ion channel is the only P2X subtype expressed in human platelets. Via transmission electron microscopy, we found that P2X1 mediates fast, reversible platelet shape change, secretory granule centralization, and pseudopodia formation. In washed human platelets, the stable P2X1 agonist alpha,beta-methylene ATP (alpha,beta-meATP) causes rapid, transient (2-5 s), and dose-dependent myosin light chain (MLC) phosphorylation, requiring extracellular Ca2+.

Fresnel diffraction effects in the frontlight for a liquid-crystal display.

In a new type of illumination system for reflective liquid-crystal displays, the frontlight, unwanted shadows appear in certain viewing directions. It will be shown that for an accurate description of these shadows the geometrical optics approach is not satisfactory and that Fresnel diffraction has to be taken into account. A model for the diffraction effects was developed, and the predicted results correspond well to the measurements.

The hemiparasitic angiosperm Bartsia alpina has the potential to accelerate decomposition in sub-arctic communities.

We investigated the hypothesis that hemiparasites accelerate nutrient cycling in nutrient-poor communities. Hemiparasites concentrate nutrients in their leaves, thus potentially producing high quality litter that releases nutrients that would otherwise remain in host tissues or in slowly decomposing plant litter. This hypothesis was tested using species from a European sub-arctic community where root hemiparasites are abundant.

Quantitative image analysis as an alternative to chemical analysis for follow-up of liver biopsies from a toucan with hemochromatosis. A technique with potential value for the follow-up of hemochromatosis in humans.

Objective: To compare the reliability of quantitative image analysis of histologic sections versus chemical analysis for determination of the iron content of serial liver biopsies taken at regular intervals after the onset of treatment, in a case of hemochromatosis in a channel-billed toucan treated with deferoxaminemesilate in combination with a low-iron diet.

Study Design: Two different image analysis systems were used, one developed for working with black-and-white pictures and another capable of processing colored images. Using Pearson's correlation test, the results with both quantitative image analysis systems were compared to the results obtained by chemical analysis.