Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 196
Filter
1.
Int J Sports Med ; 45(1): 48-54, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37972934

ABSTRACT

Patients with chronic ankle instability (CAI) consistently display postural control alterations, which may result from sensorimotor dysfunction. This study aimed to compare muscle activity in the lower extremity and postural control among individuals with CAI, copers and uninjured controls during a static balance test. A total of 57 physically active participants were categorized into three groups (CAI, copers and controls) and performed a single-leg balance test with two visual conditions: eyes open and eyes closed. Muscle activity in six lower extremity muscles and center of pressure (CoP) variables were recorded and analyzed. Patients with CAI exhibited greater muscle activity in the medial gastrocnemius and gluteus maximus compared to controls or copers, regardless of the visual condition. Copers displayed increased gluteus medius activity compared to controls. Additionally, all groups demonstrated increased muscle activity and CoP variables when visual feedback was disrupted. These findings suggest that patients with CAI may have less effective recruitment of motor units during static balance. On the other hand, greater muscle activity in the gluteus medius in copers may represent a coping mechanism to avoid further ankle injuries. Further research on muscle activity during dynamic postural control is warranted to explore sensorimotor alterations in patients with CAI.


Subject(s)
Ankle Injuries , Joint Instability , Humans , Ankle , Ankle Joint/physiology , Muscle, Skeletal/physiology , Lower Extremity , Postural Balance/physiology , Chronic Disease
2.
Gait Posture ; 107: 17-22, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37716278

ABSTRACT

BACKGROUND: Postural control measured during single-leg stance and single-leg hop stabilization has been used to estimate sensorimotor function in CAI individuals and copers. To date, studies have not used postural control tasks as a way of measuring responses to sudden changes in sensory information after simulated ankle inversion landings. RESEARCH QUESTION: A cross-sectional study was performed to identify any differences in static and dynamic postural control before and after simulated ankle inversion landings among individuals with chronic ankle instability (CAI), copers, and healthy controls. METHODS: Nineteen CAI individuals, 19 copers, and 19 controls participated in this study. Participants performed 3 static and dynamic balance tasks before and after simulated ankle inversion landings onto a 25° tilted platform from a height of 30 cm. The main outcome measures were the center of pressure (COP) velocity and range from the single-leg stance, as well as the dynamic postural stability index from the single-leg hop stabilization. The Wilcoxon signed-rank test was used to compare posttest and pretest differences in static and dynamic postural control between groups. RESULTS: In the static postural control measures, the CAI group had a higher difference in COP velocity and COP range in the frontal plane (p < 0.05 and p < 0.05, respectively) than the coper group. In the dynamic postural control measures, the CAI group demonstrated a higher difference in the vertical stability index (p < 0.05) than the healthy control group. SIGNIFICANCE: CAI individuals have persistent worse postural control after somatosensory modulation due to their inability to adapt to sudden somatosensory modulation. Relative to CAI individuals, copers may have different abilities not only the integration of somatosensory input about ankle inversion modulation, but also the adaptation of the entire motor control system, preventing recurrent ankle sprains after an initial LAS. Therefore, somatosensory modulation may be the indicator of understanding CAI and coper.


Subject(s)
Ankle Injuries , Joint Instability , Humans , Ankle , Cross-Sectional Studies , Ankle Joint , Postural Balance/physiology , Chronic Disease
3.
Gait Posture ; 107: 269-274, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37914561

ABSTRACT

BACKGROUND: Patients with chronic ankle instability (CAI) often experience injury-related fear following ankle injuries, a condition known as kinesiophobia. Little research has investigated the impact of kinesiophobia in patients with CAI. RESEARCH QUESTION: How does kinesiophobia impact the static and dynamic balance of individuals with CAI? METHODS: Fifty patients with CAI were divided into 2 subgroups based on their responses to the Tampa Scale of Kinesiophobia: 25 with kinesiophobia (CAI-K) and 25 without kinesiophobia (CAI-N). These groups were compared to 20 control participants. All participants performed a single-leg balance test with eyes open (EO) and eyes closed (EC). They also performed the Y-balance test (YBT) with EO. Romberg ratios were calculated as EC/EO and used for statistical analysis. RESULTS: No differences in static balance with EO and EC were found among three groups. However, the CAI-K group displayed a higher Romberg ratio in the mediolateral direction during static balance than both CAI-N and control groups. Additionally, both CAI-K and CAI-N groups displayed higher Romberg ratio in the anterior-posterior than controls. During YBT, the CAI-K group showed reduced reach distance in the anterior direction than CAI-N and control groups. SIGNIFICANCE: The CAI-K group relies more on visual feedback during static balance in the mediolateral direction than CAI-N and control groups. Furthermore, the CAI-K group displayed less anterior reach distance during YBT compared to the CAI-N and control groups. Clinicians should consider both psychological and physical factors when designing rehabilitation programs.


Subject(s)
Ankle Injuries , Joint Instability , Humans , Ankle , Ankle Joint , Kinesiophobia , Ankle Injuries/complications , Joint Instability/complications , Joint Instability/rehabilitation , Postural Balance/physiology , Chronic Disease
4.
Toxicol Appl Pharmacol ; 481: 116753, 2023 12 15.
Article in English | MEDLINE | ID: mdl-37951547

ABSTRACT

Exposure to nickel, an environmental respiratory toxicant, is associated with lung diseases including asthma, pulmonary fibrosis, bronchitis and cancers. Our previous studies have shown that a majority of the nickel-induced transcriptional changes are persistent and do not reverse even after the termination of exposure. This suggested transcriptional memory, wherein the cell 'remembers' past nickel exposure. Transcriptional memory, due to which the cells respond more robustly to a previously encountered stimulus has been identified in a number of organisms. Therefore, transcriptional memory has been described as an adaptive mechanism. However, transcriptional memory caused by environmental toxicant exposures has not been well investigated. Moreover, how the transcriptional memory caused by an environmental toxicant might influence the outcome of exposure to a second toxicant has not been explored. In this study, we investigated whether nickel-induced transcriptional memory influences the outcome of the cell's response to a second respiratory toxicant, nicotine. Nicotine, an addictive compound in tobacco, is associated with the development of chronic lung diseases including chronic obstructive pulmonary disease (COPD) and pulmonary fibrosis. Our results show that nicotine exposure upregulated a subset of genes only in the cells previously exposed to nickel. Furthermore, our analyses indicate robust activation of interferon (IFN) signaling in these cells. IFN signaling is a driver of inflammation, which is associated with many chronic lung diseases. Therefore, our results suggest that nicotine exposure of lung cells that retain the transcriptional memory of previous nickel exposure could result in increased susceptibility to developing chronic inflammatory lung diseases.


Subject(s)
Nickel , Pulmonary Fibrosis , Humans , Nickel/toxicity , Nicotine/toxicity , Pulmonary Fibrosis/pathology , Lung/pathology , Epithelial Cells , Interferons
5.
J Athl Train ; 2023 Nov 28.
Article in English | MEDLINE | ID: mdl-38014796

ABSTRACT

CONTEXT: Individuals with chronic ankle instability (CAI) appear to demonstrate altered movement patterns when their vision is disturbed during simple tasks such as single-leg standing and walking. However, it remains unclear whether visual disruption by stroboscopic glasses alters movement patterns during landing cutting movements, considered highly demanding sports maneuvers that mimic a typical athletic movement. OBJECTIVE: This study aimed to identify altered lower extremity kinematics and muscle activation when participants' vision was disrupted by stroboscopic glasses during landing cutting tasks in CAI patients. DESIGN: A case control design. SETTING: A controlled laboratory setting. PATIENTS OR OTHER PARTICIPANTS: Eighteen CAI patients and 18 matched healthy controls volunteered to participate in the study. All participants performed 5 trials of landing cutting with (SV) and without (NSV) stroboscopic glasses. MAIN OUTCOME MEASURES: Frontal and sagittal lower extremity kinematics, and 6 lower extremity muscle activations during the stance phase of landing cutting tasks with (SV) and without stroboscopic glasses (NSV). RESULTS: CAI patients demonstrated more inversion angle from 18% to 22% and from 60% to 100% of the stance phase and more peroneal longus activation from initial contact to 18% of the stance phase under the SV condition compared to the NSV condition. There were no differences in knee and hip joint angles between the visual conditions for both groups. CONCLUSIONS: When wearing stroboscopic glasses, CAI patients showed altered movement patterns, including increased inversion angle and peroneus longus activation during the stance phase of landing cutting. The results suggest that CAI patients may lack the ability to reweight sensory information to adapt their movement to visual disruption.

6.
Article in English | MEDLINE | ID: mdl-37922174

ABSTRACT

Visual clustering is a common perceptual task in scatterplots that supports diverse analytics tasks (e.g., cluster identification). However, even with the same scatterplot, the ways of perceiving clusters (i.e., conducting visual clustering) can differ due to the differences among individuals and ambiguous cluster boundaries. Although such perceptual variability casts doubt on the reliability of data analysis based on visual clustering, we lack a systematic way to efficiently assess this variability. In this research, we study perceptual variability in conducting visual clustering, which we call Cluster Ambiguity. To this end, we introduce CLAMS, a data-driven visual quality measure for automatically predicting cluster ambiguity in monochrome scatterplots. We first conduct a qualitative study to identify key factors that affect the visual separation of clusters (e.g., proximity or size difference between clusters). Based on study findings, we deploy a regression module that estimates the human-judged separability of two clusters. Then, CLAMS predicts cluster ambiguity by analyzing the aggregated results of all pairwise separability between clusters that are generated by the module. CLAMS outperforms widely-used clustering techniques in predicting ground truth cluster ambiguity. Meanwhile, CLAMS exhibits performance on par with human annotators. We conclude our work by presenting two applications for optimizing and benchmarking data mining techniques using CLAMS. The interactive demo of CLAMS is available at clusterambiguity.dev.

7.
Nat Commun ; 14(1): 6335, 2023 10 10.
Article in English | MEDLINE | ID: mdl-37816742

ABSTRACT

Global eradication of poliovirus remains elusive, and it is critical to develop next generation vaccines and antivirals. In support of this goal, we map the epitope of human monoclonal antibody 9H2 which is able to neutralize the three serotypes of poliovirus. Using cryo-EM we solve the near-atomic structures of 9H2 fragments (Fab) bound to capsids of poliovirus serotypes 1, 2, and 3. The Fab-virus complexes show that Fab interacts with the same binding mode for each serotype and at the same angle of interaction relative to the capsid surface. For each of the Fab-virus complexes, we find that the binding site overlaps with the poliovirus receptor (PVR) binding site and maps across and into a depression in the capsid called the canyon. No conformational changes to the capsid are induced by Fab binding for any complex. Competition binding experiments between 9H2 and PVR reveal that 9H2 impedes receptor binding. Thus, 9H2 outcompetes the receptor to neutralize poliovirus. The ability to neutralize all three serotypes, coupled with the critical importance of the conserved receptor binding site make 9H2 an attractive antiviral candidate for future development.


Subject(s)
Antibodies, Monoclonal , Poliovirus , Humans , Serogroup , Capsid Proteins/metabolism , Binding Sites , Antibodies, Viral
8.
Toxics ; 11(10)2023 Oct 20.
Article in English | MEDLINE | ID: mdl-37888723

ABSTRACT

This study aimed to assess the impact of tap water application on reducing the generation of ultrafine particles from the wheel-rail contact using a twin-disk rig under dry and wet conditions, with train velocities of 45 and 80 km/h. A small amount of 0.3 L/min tap water was applied at the wheel-rail contact, and a diffusion dryer was used to eliminate water vapor. The Fast Mobility Particle Sizer measured the number concentration (NC) of nano-sized wear particles in the range of 6 to 560 nm. The tap water application method effectively reduced the NC of ultrafine and fine particles by 67-72% and 86-88%, respectively. Positive reduction rates were observed for all diameters at 45 km/h and for most diameters, except for approximately 70 nm and 80 nm, at 80 km/h. Even with a small amount of water, this approach successfully decreased nano-sized wear particle generation. However, the potential influence of mineral crystals in tap water on NC requires further investigation. Overall, this method shows promise for enhancing air quality and public health by mitigating nano-sized wear particle generation in subway systems.

9.
Angew Chem Int Ed Engl ; 62(48): e202312928, 2023 Nov 27.
Article in English | MEDLINE | ID: mdl-37842904

ABSTRACT

High-capacity Li-rich layered oxides using oxygen redox as well as transition metal redox suffer from its structural instability due to lattice oxygen escaped from its structure during oxygen redox and the following electrolyte decomposition by the reactive oxygen species. Herein, we rescued a Li-rich layered oxide based on 4d transition metal by employing an organic superoxide dismutase mimics as a homogeneous electrolyte additive. Guaiacol scavenged superoxide radicals via dismutation or disproportionation to convert two superoxide molecules to peroxide and dioxygen after absorbing lithium superoxide on its partially negative oxygen of methoxy and hydroxyl groups. Additionally, guaiacol was decomposed to form a thin and stable cathode-electrolyte interphase (CEI) layer, endowing the cathode with the interfacial stability.

10.
Clin Biomech (Bristol, Avon) ; 109: 106096, 2023 10.
Article in English | MEDLINE | ID: mdl-37725866

ABSTRACT

BACKGROUND: Individuals with chronic ankle instability have decreased peak torque during maximum voluntary contraction in ankle evertors/invertors, and hip abductors. However, it is unclear whether individuals with chronic ankle instability and/or copers demonstrate decreased rate of torque development in ankle evertors/invertors, and hip abductors. METHODS: 54 university-aged participants (18 chronic ankle instability, 18 copers, and 18 controls) performed three maximal isometric contractions for ankle evertors and invertors, and hip abductors. Rate of torque development was defined as the linear slope of the torque-time curve during the first 200 ms of each contraction and compared between the three groups using a one-way analysis of variance (α = 0.05). FINDINGS: The chronic ankle instability group showed 38.1% less rate of torque development than the coper (P = 0.03 and d = 0.84) and 37.1% than the control groups (P = 0.03 and d = 1.03) in the ankle evertors. For the hip abductors, there were moderate effects between the chronic ankle instability group and the copers (P = 0.06 and d = 0.70), and control groups (P = 0.06 and d = 0.75). INTERPRETATIONS: The observed between-groups differences in rate of torque development indicate that restoring rate of torque development after lateral ankle sprain may be important to reduce risk of reinjury and development of chronic ankle instability. Clinicians should consider the rate of torque development in the ankle evertors and hip abductors during rehabilitation chronic ankle instability patients.


Subject(s)
Ankle Injuries , Joint Instability , Humans , Aged , Ankle , Torque , Ankle Joint , Isometric Contraction
11.
Sports Health ; : 19417381231195309, 2023 Sep 11.
Article in English | MEDLINE | ID: mdl-37697665

ABSTRACT

BACKGROUND: Knee osteoarthritis is common in older people. Serum cartilage oligomeric matrix protein (sCOMP) is a biomarker of knee articular cartilage metabolism. The purpose of this study was 2-fold: to (1) determine acute effects of running and swimming on sCOMP concentration in older people; and (2) investigate relationships between sCOMP concentration change due to running and swimming and measures of knee health in older people. HYPOTHESES: Running would result in greater increase in sCOMP concentration than swimming, and increase in sCOMP concentration due to running and swimming would associate positively with measures of poor knee health. STUDY DESIGN: Cross-sectional. LEVEL OF EVIDENCE: Level 3. METHODS: A total of 20 participants ran 5 km and 19 participants swam 1500 m. sCOMP concentration was measured immediately before, immediately after, and 15, 30, and 60 minutes after running or swimming. sCOMP concentration change due to running and swimming was compared. Correlations between sCOMP concentration change due to running and swimming, and other measures of knee health were evaluated, including the Tegner Activity Scale and Knee injury and Osteoarthritis Outcome Score. RESULTS: sCOMP concentration increased 29% immediately after running, relative to baseline, but only 6% immediately after swimming (P < 0.01). No significant relationship was observed between acute sCOMP change due to running and swimming, and observed measures of knee health (P > 0.05). Participants with clinically relevant knee symptoms exhibited greater sCOMP concentration before and after running and swimming (P = 0.03) and had greater body mass (P = 0.04). CONCLUSION: Running results in greater acute articular cartilage metabolism than swimming; however, the chronic effects of this are unclear. Older people with clinically relevant knee symptoms possess greater sCOMP concentration and are heavier, independent of exercise mode and physical activity level. CLINICAL RELEVANCE: These results describe the effects of exercise (running and swimming) for older physically active persons, with and without knee pain.

12.
Chem Commun (Camb) ; 59(80): 11963-11966, 2023 Oct 05.
Article in English | MEDLINE | ID: mdl-37724043

ABSTRACT

We investigate silicon oxycarbide nanotubes that incorporate Si, SiC, and silicon oxycarbide phases, which exhibit near zero-strain volume expansion, leading to reduced electrolyte decomposition. The composite effectively accommodates the formation of c-Li15Si4, as validated by in situ TEM analyses and electrochemical tests, thereby proposing a promising solution for Li-ion battery anodes.

13.
Angew Chem Int Ed Engl ; 62(42): e202309852, 2023 Oct 16.
Article in English | MEDLINE | ID: mdl-37635684

ABSTRACT

Conventional solid electrolyte frameworks typically consist of anions such as sulphur, oxygen, chlorine, and others, leading to inherent limitations in their properties. Despite the emergence of sulphide, oxide, and halide-based solid electrolytes for all-solid-state batteries, their utilization is hampered by issues, including the evolution of H2 S gas, the need for expensive elements, and poor contact. Here, we first introduce Prussian Blue analogue (PBA) open-framework structures as a solid electrolyte that demonstrates appreciable Na+ conductivity (>10-2 mS cm-1 ). We delve into the relationship between Na+ conductivity and the lattice parameter of N-coordinated transition metal, which is attributed to the reduced interaction between Na+ and the framework, corroborated by the distribution of relaxation times and density functional theory calculations. Among the five PBAs studied, Mn-PBA have exhibited the highest Na+ conductivity of 9.1×10-2 mS cm-1 . Feasibility tests have revealed that Mn-PBA have maintained a cycle retention of 95.1 % after 80cycles at 30 °C and a C-rate of 0.2C. Our investigation into the underlying mechanisms that play a significant role in governing the conductivity and kinetics of these materials contributes valuable insights for the development of alternative strategies to realize all-solid-state batteries.

14.
Adv Mater ; 35(38): e2303199, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37395728

ABSTRACT

The majority of waste-heat energy exists in the form of low-grade heat (<100 °C), which is immensely difficult to convert into usable energy using conventional energy-harvesting systems. Thermally regenerative electrochemical cycles (TREC), which integrate battery and thermal-energy-harvesting functionalities, are considered an attractive system for low-grade heat harvesting. Herein, the role of structural vibration modes in enhancing the efficacy of TREC systems is investigated. How changes in bonding covalency, influenced by the number of structural water molecules, impact the vibration modes is analyzed. It is discovered that even small amounts of water molecules can induce the A1g stretching mode of cyanide ligands with strong structural vibration energy, which significantly contributes to a larger temperature coefficient (ɑ) in a TREC system. Leveraging these insights, a highly efficient TREC system using a sodium-ion-based aqueous electrolyte is designed and implemented. This study provides valuable insights into the potential of TREC systems, offering a deeper understanding of the intrinsic properties of Prussian Blue analogs regulated by structural vibration modes. These insights open up new possibilities for enhancing the energy-harvesting capabilities of TREC systems.

15.
J Athl Train ; 2023 Jul 18.
Article in English | MEDLINE | ID: mdl-37459365

ABSTRACT

CONTEXT: Therapeutic interventions for individuals with chronic ankle instability (CAI) patients are recommended to improve muscle strength, postural control, and range of motions. However, their effects on neuromechanics during a drop landing remain unclear. Additionally, even though therapeutic interventions with stroboscopic glasses appear to be effective in improving postural control, it remains unclear how the utilization of stroboscopic glasses during therapeutic interventions affects landing neuromechanics. OBJECTIVES: This study utilized balance training with stroboscopic glasses to identify its effect on neuromechanics during a single leg drop landing in CAI patients. DESIGN: A randomized controlled trial. SETTING: A controlled laboratory setting. PATIENTS OR OTHER PARTICIPANTS: Fifty people with CAI were randomly assigned to one of two groups: strobe group (n=25) or control group (n=25). The 4-week rehabilitation (three sessions a week) included hop-based tasks and one-leg stance. The strobe group wore stroboscopic glasses during the training, while the control group did not. MAIN OUTCOME MEASURE(S): Ankle, knee, hip kinematics, and 4 lower extremity muscle activations 150-ms before and after initial contact during a single leg drop landing in the two groups. RESULTS: The strobe group showed greater eversion (from 150-ms before to 30-ms after the initial contact) and dorsiflexion (from 30-ms to 96-ms after the initial contact) angles and peroneal longus (from 35-ms before to 5-ms after the initial contact) and tibialis anterior (from 0-ms to 120-ms after the initial contact) activation in the posttest compared to the pretest. CONCLUSIONS: CAI patients who underwent a 4-week rehabilitation with stroboscopic glasses demonstrated changes in neuromechanics including increased dorsiflexion and eversion ankle angles and tibialis anterior and peroneus longus activation during a single leg drop landing. This finding suggests that utilization of stroboscopic glasses during rehabilitation could be beneficial in helping CAI patients develop safe landing mechanics.

16.
J Virol ; 97(7): e0016123, 2023 07 27.
Article in English | MEDLINE | ID: mdl-37367301

ABSTRACT

Parvoviruses are among the smallest and superficially simplest animal viruses, infecting a broad range of hosts, including humans, and causing some deadly infections. In 1990, the first atomic structure of the canine parvovirus (CPV) capsid revealed a 26-nm-diameter T=1 particle made up of two or three versions of a single protein, and packaging about 5,100 nucleotides of single-stranded DNA. Our structural and functional understanding of parvovirus capsids and their ligands has increased as imaging and molecular techniques have advanced, and capsid structures for most groups within the Parvoviridae family have now been determined. Despite those advances, significant questions remain unanswered about the functioning of those viral capsids and their roles in release, transmission, or cellular infection. In addition, the interactions of capsids with host receptors, antibodies, or other biological components are also still incompletely understood. The parvovirus capsid's apparent simplicity likely conceals important functions carried out by small, transient, or asymmetric structures. Here, we highlight some remaining open questions that may need to be answered to provide a more thorough understanding of how these viruses carry out their various functions. The many different members of the family Parvoviridae share a capsid architecture, and while many functions are likely similar, others may differ in detail. Many of those parvoviruses have not been experimentally examined in detail (or at all in some cases), so we, therefore, focus this minireview on the widely studied protoparvoviruses, as well as the most thoroughly investigated examples of adeno-associated viruses.


Subject(s)
Parvoviridae , Animals , Humans , Capsid/ultrastructure , Capsid Proteins/chemistry , Capsid Proteins/metabolism , DNA, Viral/metabolism , Parvoviridae/genetics , Parvoviridae/ultrastructure , Parvoviridae Infections/metabolism , Parvoviridae Infections/virology , Dependovirus/genetics , Dependovirus/metabolism , Dependovirus/ultrastructure
17.
Sports Biomech ; : 1-15, 2023 Jun 20.
Article in English | MEDLINE | ID: mdl-37339269

ABSTRACT

It remains unclear how unexpected perturbations during single-leg landings affect lower extremity kinematics and muscle activations in patients with chronic ankle instability (CAI). The purpose of this study was to identify the differences in lower extremity movement patterns among CAI subjects, copers, and healthy controls. Sixty-six people including 22 CAI subjects, 22 copers, and 22 healthy controls volunteered to participate in the study. Lower extremity joint kinematics and EMG activations from 200-ms pre to 200-ms post the initial contact during unexpected tilted landings were measured. Functional data analysis was used to evaluate between-group differences for outcome measures. Relative to copers and healthy controls, CAI subjects showed more inversion from 40-ms to 200-ms after initial contact. Relative to healthy controls, CAI subjects and copers showed more dorsiflexion. Relative to healthy controls, CAI subjects and copers showed more muscle activation in tibialis anterior and peroneus longus, respectively. In conclusion, CAI subjects demonstrated greater inversion angles and muscle activation before initial contact compared to LAS copers and healthy controls. This suggests that CAI subjects and copers prepare for their landing with protective movements, but the prepared movements shown by CAI subjects may be insufficient to reduce risk of recurrent injury.

18.
J Virol ; 97(6): e0009023, 2023 06 29.
Article in English | MEDLINE | ID: mdl-37199627

ABSTRACT

Canine parvovirus (CPV) is a small nonenveloped single-stranded DNA virus that causes serious diseases in dogs worldwide. The original strain of the virus (CPV-2) emerged in dogs during the late 1970s due to a host range switch of a virus similar to the feline panleukopenia virus that infected another host. The virus that emerged in dogs had altered capsid receptor and antibody binding sites, with some changes affecting both functions. Further receptor and antibody binding changes arose when the virus became better adapted to dogs or to other hosts. Here, we used in vitro selection and deep sequencing to reveal how two antibodies with known interactions select for escape mutations in CPV. The antibodies bound two distinct epitopes, and one largely overlapped the host receptor binding site. We also generated mutated antibody variants with altered binding structures. Viruses were passaged with wild-type (WT) or mutated antibodies, and their genomes were deep sequenced during the selective process. A small number of mutations were detected only within the capsid protein gene during the first few passages of selection, and most sites remained polymorphic or were slow to go to fixation. Mutations arose both within and outside the antibody binding footprints on the capsids, and all avoided the transferrin receptor type 1 binding footprint. Many selected mutations matched those that have arisen in the natural evolution of the virus. The patterns observed reveal the mechanisms by which these variants have been selected in nature and provide a better understanding of the interactions between antibody and receptor selections. IMPORTANCE Antibodies protect animals against infection by many different viruses and other pathogens, and we are gaining new information about the epitopes that induce antibody responses against viruses and the structures of the bound antibodies. However, less is known about the processes of antibody selection and antigenic escape and the constraints that apply in this system. Here, we used an in vitro model system and deep genome sequencing to reveal the mutations that arose in the virus genome during selection by each of two monoclonal antibodies or their mutated variants. High-resolution structures of each of the Fab:capsid complexes revealed their binding interactions. The wild-type antibodies or their mutated variants allowed us to examine how changes in antibody structure influence the mutational selection patterns seen in the virus. The results shed light on the processes of antibody binding, neutralization escape, and receptor binding, and they likely have parallels for many other viruses.


Subject(s)
Antibodies, Viral , Binding Sites, Antibody , Capsid , Parvovirus, Canine , Animals , Dogs , Capsid/metabolism , Capsid Proteins/genetics , Capsid Proteins/metabolism , Epitopes/genetics , Epitopes/analysis , Parvovirus, Canine/genetics , Parvovirus, Canine/metabolism , Mutation , Antibodies, Viral/genetics , Antibodies, Viral/metabolism , Binding Sites, Antibody/genetics , High-Throughput Nucleotide Sequencing , Antigens, Viral/metabolism , Selection, Genetic
19.
Nano Lett ; 23(8): 3582-3591, 2023 Apr 26.
Article in English | MEDLINE | ID: mdl-37027522

ABSTRACT

Over the past decade, lithium metal has been considered the most attractive anode material for high-energy-density batteries. However, its practical application has been hindered by its high reactivity with organic electrolytes and uncontrolled dendritic growth, resulting in poor Coulombic efficiency and cycle life. In this paper, we propose a design strategy for interface engineering using a conversion-type reaction of metal fluorides to evolve a LiF passivation layer and Li-M alloy. Particularly, we propose a LiF-modified Li-Mg-C electrode, which demonstrates stable long-term cycling for over 2000 h in common organic electrolytes with fluoroethylene carbonate (FEC) additives and over 700 h even without additives, suppressing unwanted side reactions and Li dendritic growth. With the help of phase diagrams, we found that solid-solution-based alloying not only facilitates the spontaneous evolution of a LiF layer and bulk alloy but also enables reversible Li plating/stripping inward to the bulk, compared with intermetallic compounds with finite Li solubility.

20.
Nat Commun ; 14(1): 2459, 2023 Apr 28.
Article in English | MEDLINE | ID: mdl-37117172

ABSTRACT

Designing highly conductive and (electro)chemical stable inorganic solid electrolytes using cost-effective materials is crucial for developing all-solid-state batteries. Here, we report halide nanocomposite solid electrolytes (HNSEs) ZrO2(-ACl)-A2ZrCl6 (A = Li or Na) that demonstrate improved ionic conductivities at 30 °C, from 0.40 to 1.3 mS cm-1 and from 0.011 to 0.11 mS cm-1 for Li+ and Na+, respectively, compared to A2ZrCl6, and improved compatibility with sulfide solid electrolytes. The mechanochemical method employing Li2O for the HNSEs synthesis enables the formation of nanostructured networks that promote interfacial superionic conduction. Via density functional theory calculations combined with synchrotron X-ray and 6Li nuclear magnetic resonance measurements and analyses, we demonstrate that interfacial oxygen-substituted compounds are responsible for the boosted interfacial conduction mechanism. Compared to state-of-the-art Li2ZrCl6, the fluorinated ZrO2-2Li2ZrCl5F HNSE shows improved high-voltage stability and interfacial compatibility with Li6PS5Cl and layered lithium transition metal oxide-based positive electrodes without detrimentally affecting Li+ conductivity. We also report the assembly and testing of a Li-In||LiNi0.88Co0.11Mn0.01O2 all-solid-state lab-scale cell operating at 30 °C and 70 MPa and capable of delivering a specific discharge of 115 mAh g-1 after almost 2000 cycles at 400 mA g-1.

SELECTION OF CITATIONS
SEARCH DETAIL
...