Viral gene drive spread during herpes simplex virus 1 infection in mice.

Gene drives are genetic modifications designed to propagate efficiently through a population. Most applications rely on homologous recombination during sexual reproduction in diploid organisms such as insects, but we recently developed a gene drive in herpesviruses that relies on co-infection of cells by wild-type and engineered viruses. Here, we report on a viral gene drive against human herpes simplex virus 1 (HSV-1) and show that it propagates efficiently in cell culture and during HSV-1 infection in mice. We describe high levels of co-infection and gene drive-mediated recombination in neuronal tissues during herpes encephalitis as the infection progresses from the site of inoculation to the peripheral and central nervous systems. In addition, we show evidence that a superinfecting gene drive virus could recombine with wild-type viruses during latent infection. These findings indicate that HSV-1 achieves high rates of co-infection and recombination during viral infection, a phenomenon that is currently underappreciated. Overall, this study shows that a viral gene drive could spread in vivo during HSV-1 infection, paving the way toward therapeutic applications.

Gene editing for latent herpes simplex virus infection reduces viral load and shedding in vivo.

Anti-HSV therapies are only suppressive because they do not eliminate latent HSV present in ganglionic neurons, the source of recurrent disease. We have developed a potentially curative approach against HSV infection, based on gene editing using HSV-specific meganucleases delivered by adeno-associated virus (AAV) vectors. Gene editing performed with two anti-HSV-1 meganucleases delivered by a combination of AAV9, AAV-Dj/8, and AAV-Rh10 can eliminate 90% or more of latent HSV DNA in mouse models of orofacial infection, and up to 97% of latent HSV DNA in mouse models of genital infection. Using a pharmacological approach to reactivate latent HSV-1, we demonstrate that ganglionic viral load reduction leads to a significant decrease of viral shedding in treated female mice. While therapy is well tolerated, in some instances, we observe hepatotoxicity at high doses and subtle histological evidence of neuronal injury without observable neurological signs or deficits. Simplification of the regimen through use of a single serotype (AAV9) delivering single meganuclease targeting a duplicated region of the HSV genome, dose reduction, and use of a neuron-specific promoter each results in improved tolerability while retaining efficacy. These results reinforce the curative potential of gene editing for HSV disease.

A multiplexed barcode approach to simultaneously evaluate gene delivery by adeno-associated virus capsid variants in nonhuman primates.

BACKGROUND AND AIMS: Adeno-associated virus (AAV) vectors are widely used to deliver therapeutic transgenes to distinct tissues, including the liver. Vectors based on naturally occurring AAV serotypes as well as vectors using engineered capsids have shown variations in tissue tropism and level of transduction between different mouse models. Moreover, results obtained in rodents frequently lack translatability into large animal studies. In light of the increasing interest in AAV vectors for human gene therapy, an increasing number of studies are being performed in nonhuman primates. To keep animal numbers to a minimum and thus optimize the process of AAV capsid selection, we developed a multiplex barcoding approach to simultaneously evaluate the in vivo vector performance for a set of serotypes and capsid-engineered AAV vectors across multiple organs. APPROACH AND RESULTS: Vector biodistribution and transgene expression were assessed by quantitative PCR, quantitative reverse transcription PCR, vector DNA amplicon Illumina sequencing and vRNAseq in male and female rhesus macaques simultaneously dosed with a mixture of barcoded naturally occurring or engineered AAV vectors encoding the same transgene. As expected, our findings show animal-to-animal variation in both the biodistribution and tissue transduction pattern, which was partly influenced by each animal's distinctive serological status. CONCLUSIONS: This method offers a robust approach to AAV vector optimization that can be used to identify and validate AAV vectors for gene delivery to potentially any anatomical site or cell type.

Implementing the donor-acceptor approach in electronically conducting copolymers via electropolymerization.

Electropolymerization has become a convenient method for synthesizing and characterizing complex organic copolymers having intrinsic electronic conductivity, including the donor (D)-acceptor (A) class of electronically conducting polymers (ECPs). This review begins with an introduction to the electrosynthesis of common second-generation ECPs. The information obtainable from electroanalytical studies, charge carriers such as polarons (positive and negative) and bipolarons (positive and negative) and doping will be discussed. The evolutionary chain of ECPs is then presented. ECPs comprising electron-rich D and electron-deficient A moieties have been shown to possess intrinsic electronic conductivity and unique optical and electronic properties. They are third generation ECPs and electropolymerization of mixtures of D and A leads to stoichiometrically controlled block copolymers. These D-A type ECPs are discussed on the basis of selected representative materials. Since the discovery of electropolymerization as a powerful tool to synthesize copolymers of conjugated monomers with a pre-determined ratio of D and A repeat units present in the polymer, the field of D-A type ECPs has grown considerably and the literature available since 2004 to 2021 is summarized and tabulated. Electronic and optical properties of the materials determined by computational chemistry are presented. The data obtained from electrochemical and optical methods are compared with those obtained from computational methods and reasons for discrepancies are given. The literature on the concept of electropolymerization extended to synthesizing triblock and many-block copolymers is reviewed. Finally, applications of D-A polymers in optoelectronic devices (organic solar cells and field-effect transistors) and in bio-imaging are explained quoting appropriate examples.

Electrocatalytic CO2 reduction on earth abundant 2D Mo2C and Ti3C2 MXenes.

Mo2C and Ti3C2 MXenes were investigated as earth-abundant electrocatalyts for the CO2 reduction reaction (CO2RR). Mo2C and Ti3C2 exhibited faradaic efficiencies of 90% (250 mV overpotential) and 65% (650 mV overpotential), respectively, for the reduction of CO2 to CO in acetonitrile using an ionic liquid electrolyte. The use of ionic liquid 1-ethyl-2-methylimidazolium tetrafluoroborate as an electrolyte in organic solvent suppressed the competing hydrogen evolution reaction. Density functional theory (DFT) calculations suggested that the catalytic active sites are oxygen vacancy sites on both MXene surfaces. Also, a spontaneous dissociation of adsorbed COOH species to a water molecule and adsorbed CO on Mo2C promote the CO2RR.

Gene editing and elimination of latent herpes simplex virus in vivo.

We evaluate gene editing of HSV in a well-established mouse model, using adeno-associated virus (AAV)-delivered meganucleases, as a potentially curative approach to treat latent HSV infection. Here we show that AAV-delivered meganucleases, but not CRISPR/Cas9, mediate highly efficient gene editing of HSV, eliminating over 90% of latent virus from superior cervical ganglia. Single-cell RNA sequencing demonstrates that both HSV and individual AAV serotypes are non-randomly distributed among neuronal subsets in ganglia, implying that improved delivery to all neuronal subsets may lead to even more complete elimination of HSV. As predicted, delivery of meganucleases using a triple AAV serotype combination results in the greatest decrease in ganglionic HSV loads. The levels of HSV elimination observed in these studies, if translated to humans, would likely significantly reduce HSV reactivation, shedding, and lesions. Further optimization of meganuclease delivery and activity is likely possible, and may offer a pathway to a cure for HSV infection.

Biomimetic System for the Application of Nanomaterials in Fluid Purification: Removal of Arsenic with Ferrihydrite.

The use of nanomaterials has transformed fields such as medicine and electronics. However, aggregation of nanomaterials in aqueous solutions, difficult recovery of spent nano-adsorbents from reactors, and a tremendous pressure loss caused by nano-adsorbents in adsorption columns have prevented the wide-scale use of nano-adsorbents in industrial applications for water purification. An over-reliance on traditional adsorption media for fluid purification practices has slowed innovation in this field. This study serves as a proof of concept for a new approach in utilizing nano-adsorbents in water treatment. A system based on the concept of renal dialysis was used to treat a solution of arsenite using two-line ferrihydrite (Fh) under environmental conditions. The performance was compared to traditional batch studies, and environmental variables pH and Eh were monitored. The system removed 67 and 91% of arsenite at 1.22 and 2.61 g/L Fh loadings, respectively, in comparison to batch experiments that removed 82 and 94% for similar loadings. Operational conditions and the physical design of the vessel limited the extent of removal that could be obtained with the system. Design advantages, shortcomings, and required improvements are discussed.

Highly Dispersed RuOOH Nanoparticles on Silica Spheres: An Efficient Photothermal Catalyst for Selective Aerobic Oxidation of Benzyl Alcohol.

Photothermal catalysis represents a promising strategy to utilize the renewable energy source (e.g., solar energy) to drive chemical reactions more efficiently. Successful and efficient photothermal catalysis relies on the availability of ideal photothermal catalysts, which can provide both large areas of catalytically active surface and strong light absorption power simultaneously. Such duplex requirements of a photothermal catalyst exhibit opposing dependence on the size of the catalyst nanoparticles, i.e., smaller size is beneficial for achieving higher surface area and more active surface, whereas larger size favors the light absorption in the nanoparticles. In this article, we report the synthesis of ultrafine RuOOH nanoparticles with a size of 2-3 nm uniformly dispersed on the surfaces of silica (SiOx) nanospheres of hundreds of nanometers in size to tackle this challenge of forming an ideal photothermal catalyst. The ultrasmall RuOOH nanoparticles exhibit a large surface area as well as the ability to activate adsorbed molecular oxygen. The SiOx nanospheres exhibit strong surface light scattering resonances to enhance the light absorption power of the small RuOOH nanoparticles anchored on the SiOx surface. Therefore, the RuOOH/SiOx composite particles represent a new class of efficient photothermal catalysts with a photothermal energy conversion efficiency of 92.5% for selective aerobic oxidation of benzyl alcohol to benzylaldehyde under ambient conditions.

Traditional Colonial-type cheese from the south of Brazil: A case to support the new Brazilian laws for artisanal cheese production from raw milk.

Artisanal Colonial-type cheese is made from raw milk and is the main cheese produced by rural families of the southern region of Brazil. The aim of this study was to investigate, identify problems, and propose solutions for the current situation of small family farms producing and informally selling artisanal Colonial-type cheese located in the western part of Santa Catarina State in Southern Brazil. A semistructured questionnaire was employed in 12 rural properties to analyze the mode of production. Physical-chemical and microbiological analyses of water, raw milk, and cheese were performed, and it was found that 92, 50, and 100% of the samples, respectively, were outside of the current Brazilian regulatory parameters. None of the cheesemakers involved in this study met the requirements, as established by law, for artisanal cheese production from raw milk. This study concluded that technical support and changes in public policy are needed to ensure the preservation of this artisanal cheese, considering the historical importance and cultural traditions of these local communities and the socioeconomic importance of cheesemaking to family farming. Furthermore, more research on the safety of the cheese produced from raw milk is needed as well as the development of specific microbiological standards for artisanal Brazilian cheeses. Public policies aimed at guaranteeing food safety that formalize the commercialization of these cheeses will increase food security in those communities that currently produce artisanal cheese informally.

High Electron Mobility of Amorphous Red Phosphorus Thin Films.

Black phosphorus (BP) has been gathering great attention for its electronic and optoelectronic applications due to its high electron mobility and high ION/OFF current switching ratio. The limitations of this material include its low synthetic yield and high cost. One alternative to BP is another type of phosphorus allotrope, red phosphorus (RP), which is much more affordable and easier to process. Although RP has been widely used in industry for hundreds of years and considered as an insulating material, in this study, we demonstrate through field-effect transistors (FET) measurements that amorphous red phosphorus (a-RP) films are semiconductive with a high mobility of 387 cm2 V-1 s-1 and a current switching ratio of ≈103 , which is comparable to the electronic characteristics previously reported for BP. The films were produced via a thermal evaporation method or a facile drop-casting approach onto Si/SiO2 substrates. We also report a study of the oxidation process of the films over time and a method to stabilize the films via doping a-RP with metal oxides. The doped films retain stability for one thousand I-V cycles, with no signs of degradation.