Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19) in humans, has a broad host range, and is able to infect domestic and wild ...animal species. Notably, white-tailed deer (WTD, Odocoileus virginianus), the most widely distributed cervid species in the Americas, were shown to be highly susceptible to SARS-CoV-2 in challenge studies and reported natural infection/exposure rates approaching 30-40% in free-ranging WTD in the U.S. Thus, understanding the infection and transmission dynamics of SARS-CoV-2 in WTD is critical to prevent future zoonotic transmission to humans, at the human-WTD interface during hunting or venison farming, and for implementation of effective disease control measures. Here, we demonstrated that following intranasal inoculation with SARS-CoV-2 B.1 lineage, WTD fawns (~8-month-old) shed infectious virus up to day 5 post-inoculation (pi), with high viral loads shed in nasal and oral secretions. This resulted in efficient deer-to-deer transmission on day 3 pi. Consistent a with lack of infectious SARS-CoV-2 shedding after day 5 pi, no transmission was observed to contact animals added on days 6 and 9 pi. We have also investigated the tropism and sites of SARS-CoV-2 replication in adult WTD (3-4 years of age). Infectious virus was detected up to day 6 pi in nasal secretions, and from various respiratory-, lymphoid-, and central nervous system tissues, indicating broad tissue tropism and multiple sites of virus replication. The study provides important insights on the infection and transmission dynamics of SARS-CoV-2 in WTD, a wild animal species that is highly susceptible to infection and with the potential to become a reservoir for the virus in the field.
Microgap and bacterial microleakage at the implant-prosthetic abutment interface are recognized concerns for implant-supported restorations, leading to inflammation of the peri-implant tissues, with ...deleterious consequences for crestal bone levels. However, little is known regarding the interface established between the implant and the healing abutment or cover screw placed for the osseointegration phase.
The purpose of this in vitro study was to characterize the implant-cover screw and implant-healing abutment interfaces of a platform-switched implant system to determine the microgap and bacterial microleakage of the system and evaluate the biological response and functionality of an interface sealing agent.
The interfacial microgaps of the implant-healing abutment and implant-cover screw interfaces were characterized by scanning electron microscopy (n=10), and bacterial microleakage was evaluated after colonization with Enterococcus faecalis in a 30-day follow-up (n=10). The sealing efficacy and irritation potential of a silicone-based sealer were determined by using the hen's egg test on chorioallantoic membrane assay. The 2-sample t test was performed to compare means between groups, and data presented with the Kaplan-Meier method were compared statistically by using the log-rank test (α=.05).
The interfacial microgap was less than 2.5 μm for both systems. Bacterial microleakage was noted in approximately 50% of the specimens, particularly at early time points, at both the healing abutment and cover screw interfaces. The silicone-based sealer prevented bacterial leakage in the experimental setting.
The implant-healing abutment and implant-cover screw interfaces of the tested system, despite the low microgap, allowed for bacterial microleakage after internal colonization. The use of a nonirritating silicone-based sealing agent effectively sealed the system.
Hydration analysis and recommendations for elite soccer players are discussed. It was proposed that right after warm-up, hydration can involve the consumption of isotonic or hypotonic drinks with 0.5 ...to 0.7g sodium/L, 4 to 6% carbohydrates concentration and osmolarity less than 270 mOsm/L. Before this, on the match day, the recommendation includes fluids ingesting 5 to 7 mL/kg of body weight 4 hours before match and if individual doesn't produce urine or urine is dark or concentrated, the recommendation includes fluids addition 3 to 5 mL/kg of body weight 2 hours before match with ad libitum water during warm-up. Thus, hydration program before match can ensure hydration by correcting fluids deficit before start activities.
.
Display omitted
► Multi-wall carbon nanotube (MWCNT) and powdered activated carbon (PAC) adsorbents. ► Reactive Red M-2BE textile dye adsorbate. ► Kinetics was followed by Avrami fractional-order. ...► The maximum adsorption capacities were 335.7 and 260.7
mg
g
−1 for MWCNT and PAC. ► Synthetic effluents treatment.
Multi-walled carbon nanotubes and powdered activated carbon were used as adsorbents for the successful removal of Reactive Red M-2BE textile dye from aqueous solutions. The adsorbents were characterised by infrared spectroscopy, N
2 adsorption/desorption isotherms and scanning electron microscopy. The effects of pH, shaking time and temperature on adsorption capacity were studied. In the acidic pH region (pH 2.0), the adsorption of the dye was favourable using both adsorbents. The contact time to obtain equilibrium at 298
K was fixed at 1
h for both adsorbents. The activation energy of the adsorption process was evaluated from 298 to 323
K for both adsorbents. The Avrami fractional-order kinetic model provided the best fit to the experimental data compared with pseudo-first-order or pseudo-second-order kinetic adsorption models. For Reactive Red M-2BE dye, the equilibrium data were best fitted to the Liu isotherm model. Simulated dyehouse effluents were used to check the applicability of the proposed adsorbents for effluent treatment.
Susceptibility to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the outcome of coronavirus disease 2019 (COVID-19) have been linked to underlying health conditions and the age of ...affected individuals. Here, we assessed the effect of age on SARS-CoV-2 infection using a ferret model. For this, young (6-month-old) and aged (18- to 39-month-old) ferrets were inoculated intranasally with various doses of SARS-CoV-2. By using infectious virus shedding in respiratory secretions and seroconversion, we estimated that the infectious dose of SARS-CoV-2 in aged animals is ∼32 PFU per animal, while in young animals it was estimated to be ∼100 PFU. We showed that viral replication in the upper respiratory tract and shedding in respiratory secretions is enhanced in aged ferrets compared to young animals. Similar to observations in humans, this was associated with higher transcription levels of two key viral entry factors, ACE2 and TMPRSS2, in the upper respiratory tract of aged ferrets.
In humans, ACE2 and TMPRSS2 are expressed in various cells and tissues, and differential expression has been described in young and old people, with a higher level of expressing cells being detected in the nasal brushing of older people than young individuals. We described the same pattern occurring in ferrets, and we demonstrated that age affects susceptibility of ferrets to SARS-CoV-2. Aged animals were more likely to get infected when exposed to lower infectious dose of the virus than young animals, and the viral replication in the upper respiratory tract and shedding are enhanced in aged ferrets. Together, these results suggest that the higher infectivity and enhanced ability of SARS-CoV-2 to replicate in aged individuals is associated, at least in part, with transcription levels of ACE2 and TMPRSS2 at the sites of virus entry. The young and aged ferret model developed here may represent a great platform to assess age-related differences in SARS-CoV-2 infection dynamics and replication.
Single-particle cryo-electron microscopy (cryo-EM SPA) has recently emerged as an exceptionally well-suited technique for determining the structure of membrane proteins (MPs). Indeed, in recent ...years, huge increase in the number of MPs solved via cryo-EM SPA at a resolution better than 3.0 Å in the Protein Data Bank (PDB) has been observed. However, sample preparation remains a significant challenge in the field. Here, we evaluated the MPs solved using cryo-EM SPA deposited in the PDB in the last two years at a resolution below 3.0 Å. The most critical parameters for sample preparation are as follows: (i) the surfactant used for protein extraction from the membrane, (ii) the surfactant, amphiphiles, nanodiscs or other molecules present in the vitrification step, (iii) the vitrification method employed, and (iv) the type of grids used. The aim is not to provide a definitive answer on the optimal sample conditions for cryo-EM SPA of MPs but rather assess the current trends in the MP structural biology community towards obtaining high-resolution cryo-EM structures.
Synthetic physiological fluids are currently used as a first in vitro bioactivity assessment for bone grafts. Our understanding about the interactions taking place at the fluid-implant interface has ...evolved remarkably during the last decade, and does not comply with the traditional International Organization for Standardization/final draft International Standard 23317 protocol in purely inorganic simulated body fluid. The advances in our knowledge point to the need of a true paradigm shift toward testing physiological fluids with enhanced biomimicry and a better understanding of the materials' structure-dissolution behavior. This will contribute to "upgrade" our vision of entire cascades of events taking place at the implant surfaces upon immersion in the testing media or after implantation. Starting from an osteoinductive bioglass composition with the ability to alleviate the oxidative stress, thin bioglass films with different degrees of polymerization were deposited onto titanium substrates. Their biomineralization activity in simulated body fluid and in a series of new inorganic-organic media with increasing biomimicry that more closely simulated the human intercellular environment was compared. A comprehensive range of advanced characterization tools (scanning electron microscopy; grazing-incidence X-ray diffraction; Fourier-transform infrared, micro-Raman, energy-dispersive, X-ray photoelectron, and surface-enhanced laser desorption/ionization time-of-flight mass spectroscopies; and cytocompatibility assays using mesenchymal stem cells) were used. The information gathered is very useful to biologists, biophysicists, clinicians, and material scientists with special interest in teaching and research. By combining all the analyses, we propose herein a step forward toward establishing an improved unified protocol for testing the bioactivity of implant materials.
Epidemiological studies reveal a link between osteoporosis and the risk of ischemic cardiovascular disease. We illustrate an association between coronary calcification and bone microarchitecture in ...older adults based on the SPAH study. This cross-sectional research comprised 256 individuals subjected to cardiac coronary computed tomography angiography (CCTA) for coronary artery calcification (CAC), high-resolution peripheral quantitative computed tomography (HR-pQCT) at the tibia and radius with standardized z score parameters, and dual-energy X-ray absorptiometry (DXA) to evaluate bone status. We used Student's t test and the Mann-Whitney and Chi-squared tests for comparison of basal measurements. Association analysis was performed using the Poisson regression model with adjustment for CAC and sex. Multivariate analysis revealed different bone variables for predicting CAC in DXA and HR-pQCT scenarios. Although most of the bone parameters are related to vascular calcification, only cortical porosity (Ct.Po) remained uniform by HR-pQCT. Results for were as follows: the tibia-women (exp β = 1.12 (95% CI 1.10-1.13, p < 0.001) and men (exp β = 1.44, 95% CI 1.42-1.46, p < 0.001); the radius-women (exp β = 1.07 (95% CI 1.07-1.08, p < 0.001) and men (exp β = 1.33 (95% CI 1.30-1.37, p < 0.001). These findings suggest an inverse relationship between CAC and cortical bone content, as assessed by HR-pQCT, with higher coronary calcification in individuals older than 65 years.
Senecavirus A (SVA), an oncolytic picornavirus used for cancer treatment in humans, has recently emerged as a vesicular disease (VD)-causing agent in swine worldwide. Notably, SVA-induced VD is ...indistinguishable from foot-and-mouth disease (FMD) and other high-consequence VDs of pigs. Here we investigated the role of apoptosis on infection and replication of SVA. Given the critical role of the nuclear factor-kappa B (NF-κB) signaling pathway on modulation of cell death, we first assessed activation of NF-κB during SVA infection. Results here show that while early during infection SVA induces activation of NF-κB, as evidenced by nuclear translocation of NF-κB-p65 and NF-κB-mediated transcription, late in infection a cleaved product corresponding to the C-terminus of NF-κB-p65 is detected in infected cells, resulting in lower NF-κB transcriptional activity. Additionally, we assessed the potential role of SVA 3C protease (3C
) in SVA-induced host-cell apoptosis and cleavage of NF-κB-p65. Transient expression of SVA 3C
was associated with cleavage of NF-κB-p65 and Poly (ADP-ribose) polymerase (PARP), suggesting its involvement in virus-induced apoptosis. Most importantly, we showed that while cleavage of NF-κB-p65 is secondary to caspase activation, the proteolytic activity of SVA 3C
is essential for induction of apoptosis. Experiments using the pan-caspase inhibitor Z-VAD-FMK confirmed the relevance of late apoptosis for SVA infection, indicating that SVA induces apoptosis, presumably, as a mechanism to facilitate virus release and/or spread from infected cells. Together, these results suggest an important role of apoptosis for SVA infection biology.
PDF
