Mutual Unbiasedness in Coarse-grained Continuous Variables

The notion of mutual unbiasedness for coarse-grained measurements of quantum continuous variable systems is considered. It is shown that while the procedure of "standard" coarse graining breaks the mutual unbiasedness between conjugate variables, this desired feature can be theoretically established and experimentally observed in periodic coarse graining. We illustrate our results in an optics experiment implementing Fraunhofer diffraction through a periodic diffraction grating, finding excellent agreement with the derived theory. Our results are an important step in developing a formal connection between discrete and continuous variable quantum mechanics.Comment: 5 pages, 3 figures + Supplemental Material (1 page) v2: Introduction expanded, minor typos correcte

Functionalized carbon nanotubes as transporters for antisense oligodeoxynucleotides

The use of DNA-based therapeutics requires efficient delivery systems to transport the DNA to their place of action within the cell. To accomplish this, we investigated multiwalled carbon nanotubes (pristine MWCNT, p-MWCNT) functionalized with hydroxyl groups via 1,3-dipolar cycloaddition. In this way, we have obtained MWCNT-f-OH with improved stability in aqueous dispersions which is an advantageous property for their use in cellular environments. Afterwards, a carrier strand oligodeoxynucleotide (CS-ODN) was adsorbed to MWCNT-f-OH followed by hybridization with a therapeutic antisense oligodeoxynucleotide (AS-ODN). The amount of adsorbed CS-ODN, as well as the complementary AS-ODN and a non-complementary oligodeoxynucleotide (NS-ODN) as reference, was directly measured by radionuclide labeling of ODNs. We show that subsequent release of AS-ODNs and NS-ODNs was possible for MWCNT-f-OH above the melting temperature of AS-ODNs at 80 °C and under physiological conditions at different pH values at 37 °C. We also show a very low influence of p-MWCNT and MWCNT-f-OH on the cell viability of the bladder carcinoma (BCa) cell line EJ28 and that both MWCNT types were internalized by EJ28. Therefore, MWCNT-f-OH represents a promising carrier able to transport and release AS-ODNs inside cells

Studying nucleoid-associated protein–DNA interactions using polymer microgels as synthetic mimics

9 p.-6 fig.-1 graph. abst.Microfluidically fabricated polymer microgels are used as an experimental platform to analyze protein–DNA interactions regulating bacterial cell division. In particular, we focused on the nucleoid-associated protein SlmA, which forms a nucleoprotein complex with short DNA binding sequences (SBS) that acts as a negative regulator of the division ring stability in Escherichia coli. To mimic the bacterial nucleoid as a dense DNA region of a bacterial cell and investigate the influence of charge and permeability on protein binding and diffusion in there, we have chosen nonionic polyethylene glycol and anionic hyaluronic acid as precursor materials for hydrogel formation, previously functionalized with SBS. SlmA binds specifically to the coupled SBS for both types of microgels while preferentially accumulating at the microgels’ surface. We could control the binding specificity by adjusting the buffer composition of the DNA-functionalized microgels. The microgel charge did not impact protein binding; however, hyaluronic acid-based microgels exhibit a higher permeability, promoting protein diffusion; thus, they were the preferred choice for preparing nucleoid mimics. The approaches described here provide attractive tools for bottom-up reconstitution of essential cellular processes in media that more faithfully reproduce intracellular environments.Financial support by the Volkswagen Foundation (“Change of Course”, Grant Agreement No. 96619) and the Spanish Government (Grant Agreements No. PID2019-104544GB-I00 and PID2022-136951NB-I00) is gratefully acknowledged.Peer reviewe

Results of the first German external quality assessment scheme for the detection of monkeypox virus DNA.

BackgroundIn May 2022, the monkeypox virus (MPXV) spread into non-endemic countries and the global community was quick to test the lessons learned from the SARS-CoV-2 pandemic. Due to its symptomatic resemblance to other diseases, like the non-pox virus varicella zoster (chickenpox), polymerase chain reaction methods play an important role in correctly diagnosing the rash-causing pathogen. INSTAND quickly established a new external quality assessment (EQA) scheme for MPXV and orthopoxvirus (OPXV) DNA detection to assess the current performance quality of the laboratory tests.MethodsWe analyzed quantitative and qualitative data of the first German EQA for MPXV and OPXV DNA detection. The survey included one negative and three MPXV-positive samples with different MPX viral loads. The threshold cycle (Ct) or other measures defining the quantification cycle (Cq) were analyzed in an assay-specific manner. A Passing Bablok fit was used to investigate the performance at laboratory level.Results141 qualitative datasets were reported by 131 laboratories for MPXV detection and 68 qualitative datasets by 65 laboratories for OPXV detection. More than 96% of the results were correctly identified as negative and more than 97% correctly identified as positive. An analysis of the reported Ct/Cq values showed a large spread of these values of up to 12 Ct/Cq. Nevertheless, there is a good correlation of results for the different MPXV concentrations at laboratory level. Only a few quantitative results in copies/mL were reported (MPXV: N = 5; OPXV: N = 2), but the results correlated well with the concentration differences between the EQA samples, which were to a power of ten each.ConclusionThe EQA results show that laboratories performed well in detecting both MPXV and OPXV. However, Ct/Cq values should be interpreted with caution when conclusions are drawn about the viral load as long as metrological traceability is not granted

Fig 1 -

Distribution of the qualitative PCR results for the four samples of the monkeypox EQA survey for A) monkeypox virus (MPXV) and B) orthopoxvirus (OPXV). Numbers in the columns represent the actual number of results for the corresponding category.</p

INSTAND Monkeypox EQA September 2022—all results.

This table contains the raw results of the EQA participants without any correction. Results that were excluded from evaluation are highlighted in orange. (XLSX)</p

Passing Bablok fit of laboratory-based Ct/Cq values (black dots) for all pairs of EQA samples, differing in concentration by a power of ten.

The Passing Bablok regression line (green) is shown with the lower and upper 95% confidence limits (red).</p

Fig 2 -

Analysis of Ct/Cq values for (A) monkeypox virus PCR results and (B) for orthopoxvirus PCR results for different test systems. The grey boxes display all results for the respective sample, and the distributions of specific manufacturer-based collectives are illustrated as smaller, colored box plots in overlay with the total results. For all boxes, the whiskers stretch from the 1st quartile—1.5*(interquartile range) to the 3rd quartile + 1.5*(interquartile range).</p

S4 Table -

Results of Levene’s test of equality of variance of the reported assay-specific Ct/Cq values per MPX positive sample for A) MPXV detection and B) OPXV detection. When equality of variance was not found (labeled in red colour), one collective (marked with *) was identified and excluded before rerun the test to be able to show the equality of the variances for the other collectives (labeled in green colour). (XLSX)</p