The beauty of symmetry: siRNA phosphorodithioate modifications reduce stereocomplexity, ease analysis, and can improve potency.

Phosphorothioates (PSs) can be essential in stabilizing therapeutic oligonucleotides against enzymatic degradation. However, unless synthesis is performed with stereodefined amidites, each PS introduces a chemically undefined stereocenter, resulting in 2 unique molecules in the final product and affecting downstream analytics and purification. Replacing the second non-bridging oxygen with sulfur results in phosphorodithioate (PS2) linkages, thereby removing the stereocenter.

Autism and duplication of 17q12q21.2 by array-CGH: a case report.

Objective: Autism spectrum disorder (ASD) affects cognitive development and social interaction on different levels. Genetic and environmental factors are associated with secondary ASD. Genetic inheritance is mainly polygenic, and 10% are copy number variations (CNVs).

Digital images are hard to resist: Teaching viewers about the effects of camera angle does not reduce the camera angle's impact on power judgments.

Digital images on the internet are often designed to manipulate viewers' interpretations. Therefore, it is important to educate viewers regarding potential effects of such techniques. We investigated whether two interventions addressing potential effects of camera angle affect the technique's effect on participants' power-related judgments of depicted persons.

[Fatigue at Long COVID].

Persistent or new symptoms after infection with SARS-CoV-2 are common and are referred to as Long COVID. Fatigue is by far the most common symptom. The current article deals with fatigue in the context of Long COVID, attempts a pathogenetic classification and makes suggestions for appropriate treatment.

Whole-cell screening of oxidative enzymes using genetically encoded sensors.

Biocatalysis is increasingly used for synthetic purposes in the chemical and especially the pharmaceutical industry. Enzyme discovery and optimization which is frequently needed to improve biocatalytic performance rely on high-throughput methods for activity determination. These methods should ideally be generic and applicable to entire enzyme families.

Believing is achieving - On the role of treatment expectation in neurofeedback applications.

In neurofeedback applications, neural activity is recorded, processed in real-time and fed back to the user in order to facilitate self-regulation of the putative neural mechanisms that underlie cognition and behavior. Numerous studies suggest that neurofeedback interventions are an efficacious treatment particularly for patients with attention-deficit/hyperactivity disorder (ADHD). In recent years, however, findings of several well-controlled studies raised doubts concerning the proposed mechanism of action behind the behavioral effect of neurofeedback.

Less Is More: Novel Hepatocyte-Targeted siRNA Conjugates for Treatment of Liver-Related Disorders.

N-acetyl-galactosamine (GalNAc) conjugation enhances liver specificity for therapeutic oligonucleotides. Here we report on a novel design with improved activity and stability compared with a triantennary design. We applied a versatile monovalent serinol-GalNAc conjugation strategy.

A hydroquinone-specific screening system for directed P450 evolution.

The direct hydroxylation of benzene to hydroquinone (HQ) under mild reaction conditions is a challenging task for chemical catalysts. Cytochrome P450 (CYP) monooxygenases are known to catalyze the oxidation of a variety of aromatic compounds with atmospheric dioxygen. Protein engineering campaigns led to the identification of novel P450 variants, which yielded improvements in respect to activity, specificity, and stability.

A Semi-Rationally Engineered Bacterial Pyrrolysyl-tRNA Synthetase Genetically Encodes Phenyl Azide Chemistry.

The site-specific incorporation of non-canonical amino acids (ncAAs) at amber codons requires an aminoacyl-tRNA synthetase and a cognate amber suppressor tRNA (tRNA ). The archaeal tyrosyl-tRNA synthetase from Methanocaldococcus jannaschii and the pyrrolysyl-tRNA synthetase (PylRS) from Methanosarcina mazei have been extensively engineered to accept a versatile set of ncAAs. The PylRS/tRNA pair from the bacterium Desulfitobacterium hafniense is functional in Escherichia coli, however, variants of this PylRS have not been reported yet.

An Enzymatic Route to α-Tocopherol Synthons: Aromatic Hydroxylation of Pseudocumene and Mesitylene with P450 BM3.

Aromatic hydroxylation of pseudocumene (1 a) and mesitylene (1 b) with P450 BM3 yields key phenolic building blocks for α-tocopherol synthesis. The P450 BM3 wild-type (WT) catalyzed selective aromatic hydroxylation of 1 b (94 %), whereas 1 a was hydroxylated to a large extent on benzylic positions (46-64 %). Site-saturation mutagenesis generated a new P450 BM3 mutant, herein named "variant M3" (R47S, Y51W, A330F, I401M), with significantly increased coupling efficiency (3- to 8-fold) and activity (75- to 230-fold) for the conversion of 1 a and 1 b.

A whole cell biocatalyst for double oxidation of cyclooctane.

A novel whole cell cascade for double oxidation of cyclooctane to cyclooctanone was developed. The one-pot oxidation cascade requires only a minimum of reaction components: resting E. coli cells in aqueous buffered medium (=catalyst), the target substrate and oxygen as environmental friendly oxidant.

Reversible silencing of cytomegalovirus genomes by type I interferon governs virus latency.

Herpesviruses establish a lifelong latent infection posing the risk for virus reactivation and disease. In cytomegalovirus infection, expression of the major immediate early (IE) genes is a critical checkpoint, driving the lytic replication cycle upon primary infection or reactivation from latency. While it is known that type I interferon (IFN) limits lytic CMV replication, its role in latency and reactivation has not been explored.

A new reporter mouse cytomegalovirus reveals maintained immediate-early gene expression but poor virus replication in cycling liver sinusoidal endothelial cells.

Background: The MCMV major immediate early promoter/enhancer (MIEP) is a bidirectional promoter that drives the expression of the three immediate early viral genes, namely ie1, ie2 and ie3. The regulation of their expression is intensively studied, but still incompletely understood.

Methods: We constructed a reporter MCMV, (MCMV-MIEPr) expressing YFP and tdTomato under the control of the MIEP as proxies of ie1 and ie2, respectively.

Leishmania promastigotes lack phosphatidylserine but bind annexin V upon permeabilization or miltefosine treatment.

The protozoan parasite Leishmania is an intracellular pathogen infecting and replicating inside vertebrate host macrophages. A recent model suggests that promastigote and amastigote forms of the parasite mimic mammalian apoptotic cells by exposing phosphatidylserine (PS) at the cell surface to trigger their phagocytic uptake into host macrophages. PS presentation at the cell surface is typically analyzed using fluorescence-labeled annexin V.

Ca2+-activated transbilayer movement of plasma membrane phospholipids in Leishmania donovani during ionomycin or thapsigargin stimulation.

The protozoan parasite Leishmania causes serious infections in humans all over the world. After being inoculated into the skin through the bite of an infected sandfly, Leishmania promastigotes must gain entry into macrophages to initiate a successful infection. Specific, surface exposed phospholipids have been implicated in Leishmania-macrophage interaction but the mechanisms controlling and regulating the plasma membrane lipid distribution remains to be elucidated.

Disruption of the lipid-transporting LdMT-LdRos3 complex in Leishmania donovani affects membrane lipid asymmetry but not host cell invasion.

Maintenance and regulation of the asymmetric lipid distribution across eukaryotic plasma membranes is governed by the concerted action of specific membrane proteins controlling lipid movement across the bilayer. Here, we show that the miltefosine transporter (LdMT), a member of the P4-ATPase subfamily in Leishmania donovani, and the Cdc50-like protein LdRos3 form a stable complex that plays an essential role in maintaining phospholipid asymmetry in the parasite plasma membrane. Loss of either LdMT or LdRos3 abolishes ATP-dependent transport of NBD-labelled phosphatidylethanolamine (PE) and phosphatidylcholine from the outer to the inner plasma membrane leaflet and results in an increased cell surface exposure of endogenous PE.

Ensuring the success of local public health workforce assessments: using a participatory-based research approach with a rural population.

Objectives: To investigate a process for comprehensive rural public health workforce data collection, and apply this process to a competency and training needs assessment of local health department (LHD) workers in the state of Kansas, USA.

Study Design: Participatory research methods were used to determine an appropriate process for data collection. Survey instruments included the Council on Linkages public health core competencies and Columbia University public health emergency preparedness competencies.

Time-resolved delta spectrometry: a method to define alarm parameters from spectral data.

Alarm parameters are in many ways different from measurements of well defined chemical substances. Being confronted with an increasing number of potentially harmful compounds as well as financial and logistic constraints, new variables (such as alarm parameters) that allow for an integrated assessment or for a first screening can be a solution. To monitor for surrogate or aggregate variables can be a useful strategy to overcome some of the constraints.

On-line monitoring for control of a pilot-scale sequencing batch reactor using a submersible UV/VIS spectrometer.

A submersible UV/VIS spectrometer was used to monitor a pilot-scale sequencing batch reactor (SBR). The instrument utilises the whole UV/VIS range between 200 and 750 nm. With just one single instrument nitrate, organic matter and suspended solids can be measured simultaneously.

Monitoring of a paper mill wastewater treatment plant using UV/VIS spectroscopy.

A submersible UV/VIS spectrometer was used to monitor a paper mill wastewater treatment plant. It utilises the UV/VIS range (200-750 nm) for simultaneous measurement of COD, filtered COD, TSS and nitrate with just a single instrument. The instrument measures in-situ, directly in the process.