Compositional asymmetry in a crystalline-amorphous block copolymer influences the phase and crystallization behaviors of its blend with an amorphous block copolymer.

This study determined the phase and crystallization behaviors of blends composed of asymmetric polystyrene-block-poly(ethylene oxide) (PS-PEO) and symmetric polystyrene-block-poly(methyl methacrylate) (PS-PMMA). The PS blocks in the various binary block copolymers exhibited nearly identical molecular weights, whereas the molecular weight ratios of PEO and PMMA varied. The compatibility of the PEO and PMMA chains aided the binary block copolymers in co-ordering in a lamellar microdomain morphology, with the PEO and PMMA blocks sharing a common microdomain. Adding short tethered PMMA chains to long tethered PEO chains led to a decrease in the common microdomain spacing and an increase in the grafting density. These behaviors increased PEO chain stretching, causing macrophase separation. The mismatch in PEO and PMMA block lengths divided the common PEO/PMMA microdomain into two sections: the coexisting PEO/PMMA section close to the microdomain interface and the neat PEO section far away from it. The high-glass-transition-temperature PMMA reduced PEO chain mobility, inhibiting PEO crystallization in the coexisting PEO/PMMA section but not in the neat PEO section. When the block length ratio of PEO to PMMA decreased, the neat PEO section narrowed. The increase in the extent of PEO confinement led to a reduction in PEO crystallizability.

PIP4K2C inhibition reverses autophagic flux impairment induced by SARS-CoV-2.

In search for broad-spectrum antivirals, we discovered a small molecule inhibitor, RMC-113, that potently suppresses the replication of multiple RNA viruses including SARS-CoV-2 in human lung organoids. We demonstrated selective dual inhibition of the lipid kinases PIP4K2C and PIKfyve by RMC-113 and target engagement by its clickable analog. Advanced lipidomics revealed alteration of SARS-CoV-2-induced phosphoinositide signature by RMC-113 and linked its antiviral effect with functional PIP4K2C and PIKfyve inhibition. We discovered PIP4K2C's roles in SARS-CoV-2 entry, RNA replication, and assembly/egress, validating it as a druggable antiviral target. Integrating proteomics, single-cell transcriptomics, and functional assays revealed that PIP4K2C binds SARS-CoV-2 nonstructural protein 6 and regulates virus-induced impairment of autophagic flux. Reversing this autophagic flux impairment is a mechanism of antiviral action of RMC-113. These findings reveal virus-induced autophagy regulation via PIP4K2C, an understudied kinase, and propose dual inhibition of PIP4K2C and PIKfyve as a candidate strategy to combat emerging viruses.

An orally bioavailable SARS-CoV-2 main protease inhibitor exhibits improved affinity and reduced sensitivity to mutations.

Inhibitors of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) main protease (Mpro) such as nirmatrelvir (NTV) and ensitrelvir (ETV) have proven effective in reducing the severity of COVID-19, but the presence of resistance-conferring mutations in sequenced viral genomes raises concerns about future drug resistance. Second-generation oral drugs that retain function against these mutants are thus urgently needed. We hypothesized that the covalent hepatitis C virus protease inhibitor boceprevir (BPV) could serve as the basis for orally bioavailable drugs that inhibit SARS-CoV-2 Mpro more efficiently than existing drugs. Performing structure-guided modifications of BPV, we developed a picomolar-affinity inhibitor, ML2006a4, with antiviral activity, oral pharmacokinetics, and therapeutic efficacy similar or superior to those of NTV. A crucial feature of ML2006a4 is a derivatization of the ketoamide reactive group that improves cell permeability and oral bioavailability. Last, ML2006a4 was found to be less sensitive to several mutations that cause resistance to NTV or ETV and occur in the natural SARS-CoV-2 population. Thus, anticipatory design can preemptively address potential resistance mechanisms to expand future treatment options against coronavirus variants.

Chemical inactivation strategies for SARS-CoV-2-infected cells and organoids.

Infectious severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) research, conducted in high-containment laboratories, requires transferring samples to lower containment labs for downstream applications, mandating sample inactivation. Here, we present a stepwise protocol for chemical inactivation of SARS-CoV-2 virus in culture supernatants or within infected cells and organoids, using eight chemical reagents validated via plaque assays. Additionally, we describe steps for troubleshooting virus inactivation, titer calculation, and log reduction. This protocol offers valuable resources for the COVID-19 research community, providing essential tools to advance research on this virus.

BoLA-DRB3 Polymorphism Associated with Bovine Leukemia Virus Infection and Proviral Load in Holstein Cattle in Egypt.

Bovine leukemia virus (BLV) is the etiological agent of enzootic bovine leukosis, the most prevalent neoplastic disease of cattle worldwide. The immune response to BLV and disease susceptibility and resistance in cattle are strongly correlated with the bovine leukocyte antigen (BoLA)-DRB3 allelic polymorphism. BLV infection continues to spread in Egypt, in part because the relationships between BLV infection, proviral load in Egypt, and BoLA-DRB3 polymorphism are unknown. Here, we identified 18 previously reported alleles in 121 Holstein cows using a polymerase chain reaction sequence-based typing method. Furthermore, BoLA-DRB3 gene polymorphisms in these animals were investigated for their influence on viral infection. BoLA-DRB3*015:01 and BoLA-DRB3*010:01 were identified as susceptible and resistant alleles, respectively, for BLV infection in the tested Holsteins. In addition, BoLA-DRB3*012:01 was associated with low PVL in previous reports but high PVL in Holstein cattle in Egypt. This study is the first to demonstrate that the BoLA-DRB3 polymorphism confers resistance and susceptibility to PVL and infections of BLV in Holstein cattle in Egypt. Our results can be useful for the disease control and eradication of BLV through genetic selection.

Anticancer pan-ErbB inhibitors reduce inflammation and tissue injury and exert broad-spectrum antiviral effects.

Targeting host factors exploited by multiple viruses could offer broad-spectrum solutions for pandemic preparedness. Seventeen candidates targeting diverse functions emerged in a screen of 4,413 compounds for SARS-CoV-2 inhibitors. We demonstrated that lapatinib and other approved inhibitors of the ErbB family of receptor tyrosine kinases suppress replication of SARS-CoV-2, Venezuelan equine encephalitis virus (VEEV), and other emerging viruses with a high barrier to resistance. Lapatinib suppressed SARS-CoV-2 entry and later stages of the viral life cycle and showed synergistic effect with the direct-acting antiviral nirmatrelvir. We discovered that ErbB1, ErbB2, and ErbB4 bind SARS-CoV-2 S1 protein and regulate viral and ACE2 internalization, and they are required for VEEV infection. In human lung organoids, lapatinib protected from SARS-CoV-2-induced activation of ErbB-regulated pathways implicated in non-infectious lung injury, proinflammatory cytokine production, and epithelial barrier injury. Lapatinib suppressed VEEV replication, cytokine production, and disruption of blood-brain barrier integrity in microfluidics-based human neurovascular units, and reduced mortality in a lethal infection murine model. We validated lapatinib-mediated inhibition of ErbB activity as an important mechanism of antiviral action. These findings reveal regulation of viral replication, inflammation, and tissue injury via ErbBs and establish a proof of principle for a repurposed, ErbB-targeted approach to combat emerging viruses.

Crystal structure of CmnB involved in the biosynthesis of the nonproteinogenic amino acid L-2,3-diaminopropionic acid.

L-2,3-Diaminopropionic acid (L-Dap) is a nonproteinogenic amino acid that plays as an important role as a building block in the biosynthesis of several natural products, including capreomycin, viomycin, zwittermicin, staphyloferrin and dapdiamide. A previous study reported that CmnB and CmnK are two enzymes that are involved in the formation of L-Dap in the biosynthesis of capreomycin. CmnB catalyzes the condensation reaction of O-phospho-L-serine and L-glutamic acid to generate N-(1-amino-1-carboxyl-2-ethyl)glutamic acid, which subsequently undergoes oxidative hydrolysis via CmnK to generate the product L-Dap. Here, the crystal structure of CmnB in complex with the reaction intermediate PLP-α-aminoacrylate is reported at 2.2 Šresolution. Notably, CmnB is the second known example of a PLP-dependent enzyme that forms a monomeric structure in crystal packing. The crystal structure of CmnB also provides insights into the catalytic mechanism of the enzyme and supports the biosynthetic pathway of L-Dap reported in previous studies.

Preparing for the next viral threat with broad-spectrum antivirals.

There is a large global unmet need for the development of countermeasures to combat hundreds of viruses known to cause human disease and for the establishment of a therapeutic portfolio for future pandemic preparedness. Most approved antiviral therapeutics target proteins encoded by a single virus, providing a narrow spectrum of coverage. This, combined with the slow pace and high cost of drug development, limits the scalability of this direct-acting antiviral (DAA) approach. Here, we summarize progress and challenges in the development of broad-spectrum antivirals that target either viral elements (proteins, genome structures, and lipid envelopes) or cellular proviral factors co-opted by multiple viruses via newly discovered compounds or repurposing of approved drugs. These strategies offer new means for developing therapeutics against both existing and emerging viral threats that complement DAAs.

Self-cooling water disinfection reactor with ultraviolet-C light-emitting diodes.

The use of ultraviolet-C (UV-C) light-emitting diodes (LEDs) as a water sterilization light source poses a serious challenge in heat dissipation. High junction temperatures reduce the radiant power and lifespan of UV-C LEDs. In this study, a novel self-cooling water disinfection reactor was developed to dissipate Joule heat from UV-C LEDs. The advantage of the self-cooling design is that cooling can be achieved without requiring additional power consumption and cooling liquid. The effects of the water flow rate and driving current of UV-C LEDs on the sterilization of Escherichia coli were investigated for a traditional flow-through reactor and a reactor with self-cooling. The experimental results indicated that an increase in driving current resulted in a considerable increase in the LED temperature of the flow-through reactor but only a marginal increase in the LED temperature of the self-cooling reactor. Under a driving current of 150 mA, the LED temperature of the self-cooling reactor was 55.5°C less than that of the flow-through reactor. The time required by the self-cooling reactor to reach the steady state decreased as the water flow rate increased. Under a flow rate of 100 mL/min, the self-cooling reactor reached the steady state within 62 and 70 s when the driving current was 100 and 150 mA, respectively. Moreover, the average irradiance and inactivation values of the self-cooling reactor were up to 16.5% and 26.0% higher than those of the flow-through reactor, respectively.

Anticancer pan-ErbB inhibitors reduce inflammation and tissue injury and exert broad-spectrum antiviral effects.

Targeting host factors exploited by multiple viruses could offer broad-spectrum solutions for pandemic preparedness. Seventeen candidates targeting diverse functions emerged in a screen of 4,413 compounds for SARS-CoV-2 inhibitors. We demonstrated that lapatinib and other approved inhibitors of the ErbB family receptor tyrosine kinases suppress replication of SARS-CoV-2, Venezuelan equine encephalitis virus (VEEV), and other emerging viruses with a high barrier to resistance. Lapatinib suppressed SARS-CoV-2 entry and later stages of the viral life cycle and showed synergistic effect with the direct-acting antiviral nirmatrelvir. We discovered that ErbB1, 2 and 4 bind SARS-CoV-2 S1 protein and regulate viral and ACE2 internalization, and they are required for VEEV infection. In human lung organoids, lapatinib protected from SARS-CoV-2-induced activation of ErbB-regulated pathways implicated in non-infectious lung injury, pro-inflammatory cytokine production, and epithelial barrier injury. Lapatinib suppressed VEEV replication, cytokine production and disruption of the blood-brain barrier integrity in microfluidic-based human neurovascular units, and reduced mortality in a lethal infection murine model. We validated lapatinib-mediated inhibition of ErbB activity as an important mechanism of antiviral action. These findings reveal regulation of viral replication, inflammation, and tissue injury via ErbBs and establish a proof-of-principle for a repurposed, ErbB-targeted approach to combat emerging viruses.

Comparison of the inactivation capacity of various UV wavelengths on SARS-CoV-2.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused a worldwide pandemic. Ultraviolet (UV) is regarded as a very powerful tool against SARS-CoV-2. However, the inactivating effects of different UV wavelengths on SARS-CoV-2 under the same conditions have hardly been compared. Here, we showed that SARS-CoV-2 cultured in Dulbecco's modified Eagle's medium and 2% fetal bovine serum was efficiently inactivated by irradiation with 222, 254, and 265 wavelengths UV, but not at 308 nm. In addition, it was revealed that UV absorption by DMEM-2% FBS is very efficient at 222 nm. Our results present potentially important information for selecting the optimum UV wavelength according to the application.

Prolonged COVID-19 symptom duration in people with systemic autoimmune rheumatic diseases: results from the COVID-19 Global Rheumatology Alliance Vaccine Survey.

OBJECTIVE: We investigated prolonged COVID-19 symptom duration, defined as lasting 28 days or longer, among people with systemic autoimmune rheumatic diseases (SARDs). METHODS: We analysed data from the COVID-19 Global Rheumatology Alliance Vaccine Survey (2 April 2021-15 October 2021) to identify people with SARDs reporting test-confirmed COVID-19. Participants reported COVID-19 severity and symptom duration, sociodemographics and clinical characteristics. We reported the proportion experiencing prolonged symptom duration and investigated associations with baseline characteristics using logistic regression. RESULTS: We identified 441 respondents with SARDs and COVID-19 (mean age 48.2 years, 83.7% female, 39.5% rheumatoid arthritis). The median COVID-19 symptom duration was 15 days (IQR 7, 25). Overall, 107 (24.2%) respondents had prolonged symptom duration (≥28 days); 42/429 (9.8%) reported symptoms lasting ≥90 days. Factors associated with higher odds of prolonged symptom duration included: hospitalisation for COVID-19 vs not hospitalised and mild acute symptoms (age-adjusted OR (aOR) 6.49, 95% CI 3.03 to 14.1), comorbidity count (aOR 1.11 per comorbidity, 95% CI 1.02 to 1.21) and osteoarthritis (aOR 2.11, 95% CI 1.01 to 4.27). COVID-19 onset in 2021 vs June 2020 or earlier was associated with lower odds of prolonged symptom duration (aOR 0.42, 95% CI 0.21 to 0.81). CONCLUSION: Most people with SARDs had complete symptom resolution by day 15 after COVID-19 onset. However, about 1 in 4 experienced COVID-19 symptom duration 28 days or longer; 1 in 10 experienced symptoms 90 days or longer. Future studies are needed to investigate the possible relationships between immunomodulating medications, SARD type/flare, vaccine doses and novel viral variants with prolonged COVID-19 symptoms and other postacute sequelae of COVID-19 among people with SARDs.

In Situ Thermal Safety Aspect of the Electrospun Polyimide-Al2O3 Separator Reveals Less Exothermic Heat Energies Than Polypropylene at the Thermal Runaway Event of Lithium-Ion Batteries.

Polyimide-Al2O3 membranes are developed as a direct alternative to current polyolefin separators by the electrospinning technique and their chemical structures confirm the carbonyl group with the presence of asymmetric and symmetric stretching and bending vibrations at 1778, 1720, and 720 cm-1 and stretching vibration at 1373 cm-1 for the imide group. Porous nanofiber architecture morphology is realized with a nanofiber thickness of ∼200 nm and shows an ultrasmooth surface and >1 µm pore size in the architecture, built with the chemical constituents of carbon, nitrogen, aluminum, and oxygen elements. The galvanostatic cycling study of the Li/PI-Al2O3/LiFePO4 lithium cell delivers stable charge-discharge capacities of 144/143 mAh g-1 at 0.2 C and 110/100 mAh g-1 at 1 C for 1-100 cycles. The fabricated MCMB/PI-Al2O3/LiFePO4 lithium-ion full-cell reveals less charge transfer resistance of Rct ∼ 25 Ω and yields stable charge-discharge capacities of 125/119 mAh g-1. The thermogravimetric curve for the PI-Al2O3 separator discloses thermal stability up to 525 °C, and the differential scanning calorimetric curve shows a straight line until 300 °C and depicts high thermal stability than the PP separator. In situ multimode calorimetry analysis of the MCMB/PP/LiFePO4 full-cell showed a pronounced exothermic peak at 225 °C with a higher released heat energy of 211 J g-1 at the thermal runaway event, while the MCMB/PI-Al2O3/LiFePO4 full-cell revealed an almost 8-fold less exothermic released heat energy of 25 J g-1 than the Celgard polypropylene separator, which was because the MCMB anode and LiFePO4 cathode can be mechanically isolated without any additional separator's melting and burning reactions, as a fire-suppressant separator for lithium-ion batteries.

Numb-associated kinases are required for SARS-CoV-2 infection and are cellular targets for antiviral strategies.

The coronavirus disease 2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to pose serious threats to global health. We previously reported that AAK1, BIKE and GAK, members of the Numb-associated kinase family, control intracellular trafficking of multiple RNA viruses during viral entry and assembly/egress. Here, using both genetic and pharmacological approaches, we probe the functional relevance of NAKs for SARS-CoV-2 infection. siRNA-mediated depletion of AAK1, BIKE, GAK, and STK16, the fourth member of the NAK family, suppressed SARS-CoV-2 infection in human lung epithelial cells. Both known and novel small molecules with potent AAK1/BIKE, GAK or STK16 activity suppressed SARS-CoV-2 infection. Moreover, combination treatment with the approved anti-cancer drugs, sunitinib and erlotinib, with potent anti-AAK1/BIKE and GAK activity, respectively, demonstrated synergistic effect against SARS-CoV-2 infection in vitro. Time-of-addition experiments revealed that pharmacological inhibition of AAK1 and BIKE suppressed viral entry as well as late stages of the SARS-CoV-2 life cycle. Lastly, suppression of NAKs expression by siRNAs inhibited entry of both wild type and SARS-CoV-2 pseudovirus. These findings provide insight into the roles of NAKs in SARS-CoV-2 infection and establish a proof-of-principle that pharmacological inhibition of NAKs can be potentially used as a host-targeted approach to treat SARS-CoV-2 with potential implications to other coronaviruses.

Carbon fibre-supported hierarchical NiCo layered double hydroxide nanosheets as non-enzymatic glucose sensors for sport drinks and serum.

We report a systematic study of carbon fibre (CF)-supported NiCo layered double hydroxide nanosheets (LDHNs) with and without heat treatment at 200 and 400 °C (CF-NiCo LDHN200 and CF-NiCo oxide nanoparticles (NPs), respectively) as catalysts and sensors for glucose oxidation reactions (GORs). Tafel measurements for the GORs showed that the exchange current density of CF-NiCo LDHN was 1.91 × 10-3 mA·cm-2 at an early rest potential of -0.422 V. This was markedly higher than those of CF-NiCo LDHN200 (1.22 × 10-3 mA·cm-2 at - 0.352 V) and CF-NiCo oxide NP (1.18 × 10-3 mA·cm-2 at -0.327 V). The electron transfer number and Tafel slopes suggested that the glucose dehydrogenation step and one-electron release occurred first in the GORs. Amperometric measurements revealed high recoveries (101.92% and 98.92%) and low relative standard deviations (1.98% and 2.34%) for the determination of glucose using the CF-NiCo LDHN in sports drink samples and human serum.

Association between BoLA-DRB3 polymorphism and bovine leukemia virus proviral load in Vietnamese Holstein Friesian cattle.

Bovine leukemia virus (BLV) is the causative agent of enzootic bovine leukosis. Polymorphism in bovine leukocyte antigen (BoLA)-DRB3 allele can influence the host immune response to pathogens, including BLV. However, association between specific BoLA-DRB3 alleles and BLV proviral load (PVL), which is a useful index for estimating disease progression and transmission risk, in Vietnamese cattle are unknown. Here, association study of BoLA-DRB3 allele frequency between cattle with high or low PVL demonstrated BoLA-DRB3*12:01 associates with high PVL in Vietnamese Holstein Friesian (HF) crossbred cattle. This is the first study to demonstrate that BoLA-DRB3 polymorphism confers susceptibility to BLV high PVL in HF crossbred kept in Vietnam. Our results may be useful in disease control and eradiation for BLV through genetic selection.

Disseminated Fungal Infection and Fungemia Caused by Trichosporon asahii in a Captive Plumed Basilisk (Basiliscus plumifrons).

Trichosporon spp. are heavily arthroconidiating fungi and widely distributed in nature. Due to the similar fungal morphology, confusion among Trichosporon spp., Geotrichum spp., and Nannizziopsis spp. in reptiles is apparent and cannot be overlooked. Although few reptile Trichosporon isolates have been examined using the newer speciation criteria, the information on Trichosporon asahii in reptiles is still scarce. In the present study, we report the case of disseminated fungal infection and fungemia caused by T. asahii in a captive plumed basilisk (Basiliscus plumifrons). Multiple 0.2-0.5 cm, irregularly shaped, ulcerative nodules on the left hind foot were observed. The animal died due to the non-responsiveness to treatment. A microscopic evaluation revealed the fungal infection that primarily affected the left hind foot and right lung lobe with fungal embolisms in the lung and liver. The molecular identification of the fungal species by the DNA sequences of the ITS regions and D1/D2 gene from the fungal culture and ITS regions, from formalin-fixed paraffin-embedded (FFPE) lung tissues, were completely matched to those of T. asahii. The current report describes the first confirmed case of disseminated fungal infection and fungemia caused by T. asahii in a captive plumed basilisk.

Early experience of COVID-19 vaccination in adults with systemic rheumatic diseases: results from the COVID-19 Global Rheumatology Alliance Vaccine Survey.

BACKGROUND: We describe the early experiences of adults with systemic rheumatic disease who received the COVID-19 vaccine. METHODS: From 2 April to 30 April 2021, we conducted an online, international survey of adults with systemic rheumatic disease who received COVID-19 vaccination. We collected patient-reported data on clinician communication, beliefs and intent about discontinuing disease-modifying antirheumatic drugs (DMARDs) around the time of vaccination, and patient-reported adverse events after vaccination. RESULTS: We analysed 2860 adults with systemic rheumatic diseases who received COVID-19 vaccination (mean age 55.3 years, 86.7% female, 86.3% white). Types of COVID-19 vaccines were Pfizer-BioNTech (53.2%), Oxford/AstraZeneca (22.6%), Moderna (21.3%), Janssen/Johnson & Johnson (1.7%) and others (1.2%). The most common rheumatic disease was rheumatoid arthritis (42.3%), and 81.2% of respondents were on a DMARD. The majority (81.9%) reported communicating with clinicians about vaccination. Most (66.9%) were willing to temporarily discontinue DMARDs to improve vaccine efficacy, although many (44.3%) were concerned about rheumatic disease flares. After vaccination, the most reported patient-reported adverse events were fatigue/somnolence (33.4%), headache (27.7%), muscle/joint pains (22.8%) and fever/chills (19.9%). Rheumatic disease flares that required medication changes occurred in 4.6%. CONCLUSION: Among adults with systemic rheumatic disease who received COVID-19 vaccination, patient-reported adverse events were typical of those reported in the general population. Most patients were willing to temporarily discontinue DMARDs to improve vaccine efficacy. The relatively low frequency of rheumatic disease flare requiring medications was reassuring.

UVC disinfects SARS-CoV-2 by induction of viral genome damage without apparent effects on viral morphology and proteins.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been a pandemic threat worldwide and causes severe health and economic burdens. Contaminated environments, such as personal items and room surfaces, are considered to have virus transmission potential. Ultraviolet C (UVC) light has demonstrated germicidal ability and removes environmental contamination. UVC has inactivated SARS-CoV-2; however, the underlying mechanisms are not clear. It was confirmed here that UVC 253.7 nm, with a dose of 500 µW/cm2, completely inactivated SARS-CoV-2 in a time-dependent manner and reduced virus infectivity by 10-4.9-fold within 30 s. Immunoblotting analysis for viral spike and nucleocapsid proteins showed that UVC treatment did not damage viral proteins. The viral particle morphology remained intact even when the virus completely lost infectivity after UVC irradiation, as observed by transmission electronic microscopy. In contrast, UVC irradiation-induced genome damage was identified using the newly developed long reverse-transcription quantitative-polymerase chain reaction (RT-qPCR) assay, but not conventional RT-qPCR. The six developed long RT-PCR assays that covered the full-length viral genome clearly indicated a negative correlation between virus infectivity and UVC irradiation-induced genome damage (R2 ranging from 0.75 to 0.96). Altogether, these results provide evidence that UVC inactivates SARS-CoV-2 through the induction of viral genome damage.