Enhancing Colorimetric Detection of Nucleic Acids on Nitrocellulose Membranes: Cutting-Edge Applications in Diagnostics and Forensics.

This study re-introduces a protein-free rapid test method for nucleic acids on paper based lateral flow assays utilizing special multichannel nitrocellulose membranes and DNA-Gold conjugates, achieving significantly enhanced sensitivity, easier protocols, reduced time of detection, reduced costs of production and advanced multiplexing possibilities. A protein-free nucleic acid-based lateral flow assay (NALFA) with a limit of detection of 1 pmol of DNA is shown for the first time. The total production duration of such an assay was successfully reduced from the currently known several days to just a few hours. The simplification and acceleration of the protocol make the method more accessible and practical for various applications. The developed method supports multiplexing, enabling the simultaneous detection of up to six DNA targets. This multiplexing capability is a significant improvement over traditional line tests and offers more comprehensive diagnostic potential in a single assay. The approach significantly reduces the run time compared to traditional line tests, which enhances the efficiency of diagnostic procedures. The protein-free aspect of this assay minimizes the prevalent complications of cross-reactivity in immunoassays especially in cases of multiplexing. It is also demonstrated that the NALFA developed in this study is amplification-free and hence does not rely on specialized technicians, nor does it involve labour-intensive steps like DNA extraction and PCR processes. Overall, this study presents a robust, efficient, and highly sensitive platform for DNA or RNA detection, addressing several limitations of current methods documented in the literature. The advancements in sensitivity, cost reduction, production time, and multiplexing capabilities mark a substantial improvement, holding great potential for various applications in diagnostics, forensics, and molecular biology.

Complete Genome Sequence of the Type Strain Aliivibrio fischeri DSM 507.

The complete genome sequence of the type strain Aliivibrio fischeri comb. nov. DSM 507 is presented. The genome consists of two circular chromosomes comprising 2,970,859 bp (chromosome 1) and 1,532,347 bp (chromosome 2) with GC contents of 38.94 and 37.13%, respectively.

Steroid-Sensitive, but Not Steroid-Dependent or Steroid-Resistant Acute Graft-versus-Host Disease, Results in Similar Infection Risk as No Graft-versus-Host Disease following Allogeneic Hematopoietic Cell Transplantation.

Patients with acute graft-versus-host disease (GVHD) have an increased risk for infectious complications after allogeneic hematopoietic cell transplantation (HCT), but the risk according to response to therapy has not been well studied. We performed a retrospective analysis of the infectious complications for 1 year following allogeneic HCT at the University of Minnesota including 1143 pediatric and adult patients with and without aGVHD. The patients with aGVHD were classified into treatment response groups based on response to corticosteroids as first-line therapy: steroid-sensitive (SS; n = 114), steroid-resistant (SR; n = 103), and steroid-dependent (SD; n = 168) aGVHD. We observed that the cumulative incidence and density of infections in patients with SS aGVHD parallel the values in patients without GVHD. Infection density (ie, number of infections occurring per 100 days at risk) was greater in the patients with aGVHD compared with patients in both early and later post-transplantation periods. In GVHD patients, among the infections developed from the onset of aGVHD through 80 days of treatment, and until 1 year following transplantation, SS and SD patients had fewer bacterial and viral infections than SR patients. The overlap of nonrelapse mortality between SS and SD GVHD patients is a function of SD GVHD being responsive to steroid therapy, even if continued therapy is required. In summary, although valid goals may include reducing unneeded antibacterial antibiotic therapy and preserving microbiome diversity, these data suggest that anti-infective therapy is justified by the density of infections observed during active GVHD treatment.

Mobility of bound water in PNIPAM microgels.

Polymer-solvent interactions play a crucial role in the stimuli-responsive behaviour of polymer networks. They influence the swelling/deswelling behaviour as well as the dynamics of the polymer chains. Scattering experiments provide insight into the polymer-water interaction of poly(N-isopropylacrylamide) (PNIPAM) microgels cross-linked with N,N'-methylenebisacrylamide (BIS) in dried and humidified state. The water mobility is studied by means of neutron spin-echo spectroscopy and neutron backscattering spectroscopy. The residual water amount has been determined with Karl Fischer titration. For both degrees of humidification, the relaxation time of the water molecules is much larger than that of free water due to the strong interactions with the polymer network and is only weakly depending on temperature and length scale of observation. The possible influence of the water on methyl group rotations is discussed.

Understanding near-surface polymer dynamics by a combination of grazing-incidence neutron scattering and virtual experiments.

Neutron spin-echo spectroscopy is a unique experimental method for the investigation of polymer dynamics. The combination of neutron spin-echo spectroscopy with grazing-incidence geometry (GINSES) opens the possibility to probe the dynamics of soft-matter materials in the vicinity of the solid substrate in the time range up to 100 ns. However, the usage of the GINSES technique has some peculiarities and, due to the novelty of the method and complexity of the scattering geometry, difficulties in further data analysis occur. The current work discusses how virtual experiments within the distorted-wave Born approximation using the BornAgain software can improve GINSES data treatment and aid the understanding of polymer dynamics in the vicinity of the solid surface. With two examples, poly(N-isopropyl acrylamide) brushes and poly(ethylene glycol) microgels on Si surfaces, the simulation as well as the application of the simulation to the GINSES data analysis are presented. The approach allowed a deeper insight to be gained of the background effect and scattering contribution of different layers.

Steroid-dependent acute GVHD after allogeneic hematopoietic cell transplantation: risk factors and clinical outcomes.

Acute graft-versus-host disease (aGVHD) has various risk factors and outcomes. We defined distinct aGVHD treatment response groups based on response to first-line corticosteroids: steroid sensitive (SS), steroid resistant (SR), and the rarely studied steroid dependent (SD) aGVHD. In 1143 consecutive adult and pediatric allogeneic hematopoietic cell transplant recipients, 385 (34%) developed aGVHD, with 10% having SS aGVHD, 9% SD aGVHD, and 14% SR aGVHD. The only factor significantly associated with SD in comparison with SS was older age (odds ratio [OR], 3.9; 95% confidence interval [CI], 1.4-11.3, when comparing 18- to 60-year-olds with <18-year-olds). Factors significantly associated with SR in comparison with SS were unrelated donor (OR, 3.0; 95% CI, 1.2-7.4) and Minnesota high-risk aGVHD (OR, 2.4; 95% CI, 1.3-4.6). SR aGVHD was independently associated with higher risk for 2-year overall mortality (hazards ratio [HR], 1.8; 95% CI, 1.2-2.8) and nonrelapse mortality (NRM; HR, 2.1; 95% CI, 1.2-3.9). SS and SD GVHD groups had similar overall survival and NRM. The cumulative incidence of chronic GVHD was highest in the SD group, followed by the SR and SS groups (46%, 41%, and 29%, respectively). SD and SS GVHD had similar prognoses, both markedly better than those of the SR groups.

Inner structure and dynamics of microgels with low and medium crosslinker content prepared via surfactant-free precipitation polymerization and continuous monomer feeding approach.

The preparation of poly(N-isopropylacrylamide) microgels via classical precipitation polymerization (batch method) and a continuous monomer feeding approach (feeding method) leads to different internal crosslinker distributions, i.e., from core-shell-like to a more homogeneous one. The internal structure and dynamics of these microgels with low and medium crosslinker concentrations are studied with dynamic light scattering and small-angle neutron scattering in a wide q-range below and above the volume phase transition temperature. The influence of the preparation method, and crosslinker and initiator concentration on the internal structure of the microgels is investigated. In contrast to the classical conception where polymer microgels possess a core-shell structure with the averaged internal polymer density distribution within the core part, a detailed view of the internal inhomogeneities of the PNIPAM microgels and the presence of internal domains even above the volume phase transition temperature, when polymer microgels are in the deswollen state, are presented. The correlation between initiator concentration and the size of internal domains that appear inside the microgel with temperature increase is demonstrated. Moreover, the influence of internal inhomogeneities on the dynamics of the batch- and feeding-microgels studied with neutron spin-echo spectroscopy is reported.

A comparison of the network structure and inner dynamics of homogeneously and heterogeneously crosslinked PNIPAM microgels with high crosslinker content.

Poly(N-isopropylacrylamide) microgel particles were prepared via a "classical" surfactant-free precipitation polymerization and a continuous monomer feeding approach. It is anticipated that this yields microgel particles with different internal structures, namely a dense core with a fluffy shell for the classical approach and a more even crosslink distribution in the case of the continuous monomer feeding approach. A thorough structural investigation of the resulting microgels with dynamic light scattering, atomic force microscopy and small angle neutron scattering was conducted and related to neutron spin echo spectroscopy data. In this way a link between structural and dynamic features of the internal polymer network was made.