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1.
Dissertation Abstracts International: Section B: The Sciences and Engineering ; 84(8-B):No Pagination Specified, 2023.
Article in English | APA PsycInfo | ID: covidwho-20243072

ABSTRACT

Social isolation has been a growing concern since the onset of the COVID-19 pandemic, disproportionately impacting older adults. Social isolation can impact the physical, mental, and emotional health of older adults. The purpose of this study was to examine coping strategies of older adults living in senior living communities, as well as the supportive efforts of the team members working in such communities, to determine best practices for combating social isolation for older adults. This qualitative study was guided by the research question: How do older adults perceive loneliness, social isolation, and social connectedness living in senior living communities? Guided by the theoretical frameworks of socioemotional selectivity theory (SST) and strength and vulnerability integration model (SAVI), this study explored how diminished time horizons impact the prioritization of social connections. This qualitative study collected data through semi-structured interviews from older adults living in senior living communities in the United States. Several themes emerged from the data including Parameters of Social Connection, Dining Room as a Hub of Socialization, Time Horizon Awareness and Compensation, Strategies of Connection, and Loss of Spouse. Several implications for best practices are also discussed. (PsycInfo Database Record (c) 2023 APA, all rights reserved)

2.
J Adult Dev ; : 1-12, 2022 Nov 05.
Article in English | MEDLINE | ID: covidwho-20242799

ABSTRACT

Drawing on socioemotional selectivity theory, we examined the effect of COVID-19 lockdowns on perceptions of romantic relationships quality among older, compared to younger, adults. During the first lockdown in Israel which involved strict restrictions on movement and association with others, 280 adults aged 25-81 reported positive and negative qualities of their romantic relationship. Of these, 105 participants completed the survey again once lockdown restrictions were lifted. Contrary to our hypotheses, no evidence for age differences in the effect of the lockdown on positive or negative perceptions of relationship quality was detected. In addition, the lockdown did not influence participants' positive and negative perceptions of their romantic partners. However, we did find that, whereas people of all ages represent positive and negative qualities of their romantic partners as separate constructs, the negative association between the two is weaker for older adults compared to younger adults during (but not after) the lockdown. This finding suggests that in stressful times, older adults are better able to avoid negative perceptions clouding positive perceptions and see positive aspects of relationships with romantic partners in the face of negative ones. Findings extend evidence for age associations with complex emotional experiences to emotional aspects of interpersonal relationships. Findings enrich the theoretical understanding of age-related advantages in emotional well-being and may inform potential interventions for improving emotional health and well-being during times of crisis. Supplementary Information: The online version contains supplementary material available at 10.1007/s10804-022-09431-6.

3.
J Enzyme Inhib Med Chem ; 38(1): 2201402, 2023 Dec.
Article in English | MEDLINE | ID: covidwho-2308396

ABSTRACT

Vibrio cholerae causes life-threatening infections in low-income countries due to the rise of antibacterial resistance. Innovative pharmacological targets have been investigated and carbonic anhydrases (CAs, EC: 4.2.1.1) encoded by V. cholerae (VchCAs) emerged as a valuable option. Recently, we developed a large library of para- and meta-benzenesulfonamides characterised by moieties with a different flexibility degree as CAs inhibitors. Stopped flow-based enzymatic assays showed strong inhibition of VchαCA for this library, while lower affinity was detected against the other isoforms. In particular, cyclic urea 9c emerged for a nanomolar inhibition of VchαCA (KI = 4.7 nM) and high selectivity with respect to human isoenzymes (SI≥ 90). Computational studies revealed the influence of moiety flexibility on inhibitory activity and isoform selectivity and allowed accurate SARs. However, although VchCAs are involved in the bacterium virulence and not in its survival, we evaluated the antibacterial activity of such compounds, resulting in no direct activity.


Subject(s)
Carbonic Anhydrases , Vibrio cholerae , Humans , Structure-Activity Relationship , Molecular Structure , Carbonic Anhydrase Inhibitors/pharmacology , Carbonic Anhydrase Inhibitors/chemistry , Dose-Response Relationship, Drug , Carbonic Anhydrases/metabolism
4.
Life (Basel) ; 13(4)2023 Apr 11.
Article in English | MEDLINE | ID: covidwho-2301666

ABSTRACT

DSPAα1 is a potent rude thrombolytic protein with high medicative value. DSPAα1 has two natural N-glycan sites (N153Q-S154-S155, N398Q-K399-T400) that may lead to immune responses when administered in vivo. We aimed to study the effect of its N-glycosylation sites on DSPAα1 in vitro and in vivo by mutating these N-glycosylation sites. In this experiment, four single mutants and one double mutant were predicted and expressed in Pichia pastoris. When the N398Q-K399-T400 site was mutated, the fibrinolytic activity of the mutant was reduced by 75%. When the N153Q-S154-S155 sites were inactivated as described above, the plasminogen activating activity of its mutant was reduced by 40%, and fibrin selectivity was significantly reduced by 21-fold. The introduction of N-glycosylation on N184-G185-A186T and K368N-S369-S370 also considerably reduced the activity and fibrin selectivity of DSPAα1. The pH tolerance and thermotolerance of all mutants did not change significantly. In vivo experiments also confirmed that N-glycosylation mutations can reduce the safety of DSPAα1, lead to prolonged bleeding time, non-physiological reduction of coagulation factor (α2-AP, PAI) concentration, and increase the risk of irregular bleeding. This study ultimately demonstrated the effect of N-glycosylation mutations on the activity and safety of DSPAα1.

5.
36th IEEE International Conference on Micro Electro Mechanical Systems, MEMS 2023 ; 2023-January:433-436, 2023.
Article in English | Scopus | ID: covidwho-2273127

ABSTRACT

We have designed, fabricated, and tested a MEMS-based impedance biosensor for accurate and rapid detection of severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) using of clinical samples. The device consists of focusing region that concentrate low quantities of the virus present in the samples to a detectable threshold, trap region hat maximize the captured virus, and detection region to detect the virus with high selectivity and sensitivity, using an array of interdigitated electrodes (IDE) coated with a specific antibody. Changes in the impedance value due to the binding of the SARS-COV-2 antigen to the antibody will indicate positive or negative result. The device was able to detect inactivated SARS-COV-2 antigen present in phosphate buffer saline (PBS) with a concentration as low as 50 TCID50/ml in 30 minutes. In addition, the biosensor was able to detect SARS-COV-2 in clinical samples (swabs) with a sensitivity of 84 TCID50/ml, also in 30 minutes. © 2023 IEEE.

6.
Antibiotiki i Khimioterapiya ; 67(9-10):35-41, 2022.
Article in Russian | EMBASE | ID: covidwho-2265649

ABSTRACT

Interferons (IFN) have antiviral activity against many viruses, including SARS-CoV-2. A combination of IFN-a2b and the antioxidant taurine is widely used in the Russian Federation, and its antiviral activity has not been studied before. The aim of this study was to determine the antiviral activity of interferon drugs, in combination with taurine and without it. The study included cytotoxicity and antiviral activity assays of IFN-a2b preparations, when stored according to the instructions at 2-8degreeC, and after 1 month storage at the temperature of 20-26degreeC in a pre-opened state. The combination of IFN alpha-2b with taurine has a higher antiviral activity compared to IFN alpha-2b mono-preparation by more than 25% at a <<low>> and 85% at a <<high>> multiplicity of infection. Selectivity index for combinations of IFN-a2b (50,000 IU/dose) + taurine (1 mg/ml) and IFN-a2b (10,000 IU/ml) + taurine (0.8 mg/ml) was more than 600 units, whereas for the IFN-a2b (10,000 IU/ml) it was 200 units. Antiviral activity does not change after one month at room temperature. The combination of interferon with taurine at high concentrations was less toxic than interferon. The results obtained demonstrate practicability of interferon alpha-2b and taurine combination use for treatment and prevention of COVID-19.Copyright © Team of Authors, 2022.

7.
Inorganics ; 11(2):60, 2023.
Article in English | ProQuest Central | ID: covidwho-2262259

ABSTRACT

Two tetranuclear [Zn4Cl2(ClQ)6]·2DMF (1) and [Zn4Cl2(ClQ)6(H2O)2]·4DMF (2), as well as three dinuclear [Zn2(ClQ)3(HClQ)3]I3 (3), [Zn2(dClQ)2(H2O)6(SO4)] (4) and [Zn2(dBrQ)2(H2O)6(SO4)] (5), complexes (HClQ = 5-chloro-8-hydroxyquinoline, HdClQ = 5,7-dichloro-8-hydroxyquinoline and HdBrQ = 5,7-dibromo-8-hydroxyquinoline) were prepared as possible anticancer or antimicrobial agents and characterized by IR spectroscopy, elemental analysis and single crystal X-ray structure analysis. The stability of the complexes in solution was verified by NMR spectroscopy. Antiproliferative activity and selectivity of the prepared complexes were studied using in vitro MTT assay against the HeLa, A549, MCF-7, MDA-MB-231, HCT116 and Caco-2 cancer cell lines and on the Cos-7 non-cancerous cell line. The most sensitive to the tested complexes was Caco-2 cell line. Among the tested complexes, complex 3 showed the highest cytotoxicity against all cell lines. Unfortunately, all complexes showed only poor selectivity to normal cells, except for complex 5, which showed a certain level of selectivity. Antibacterial potential was observed for complex 5 only. Moreover, the DNA/BSA binding potential of complexes 1–3 was investigated by UV-vis and fluorescence spectroscopic methods.

8.
New Journal of Chemistry ; 2023.
Article in English | EMBASE | ID: covidwho-2260895

ABSTRACT

Here, we report a solvent- and metal-free methodology for the aminochalcogenation of alkenes, using molecular iodine as a catalyst, DMSO as a stoichiometric oxidant, and different nucleophiles under microwave irradiation. This ecofriendly approach provided the desired products with good to excellent yields in just 20 minutes. In addition, twenty compounds obtained by this methodology were referred for evaluation of potential antiviral activity against the coronavirus SARS-CoV-2. Two of the evaluated compounds (named 4d and 5b) showed potent antiviral activity, with a low cytotoxic profile resulting in a promising selectivity index.Copyright © 2023 The Royal Society of Chemistry.

9.
Internet Research ; 33(1):280-307, 2023.
Article in English | ProQuest Central | ID: covidwho-2289066

ABSTRACT

PurposeThis research created a theoretical framework based on theory of consumption values (TCV) and theory of perceived risk (TPR) to investigate the determinant factors behind consumers' intention to use health and fitness apps during the COVID-19-related lockdown. In addition, based on selectivity hypothesis theory (SHT), this study also explored how gender differences moderate the relationships between the determinants and consumers' behavioral intention.Design/methodology/approachA total of 613 respondents completed a self-reported online questionnaire. Structural equation modeling was conducted to test the role of potential determinants in influencing consumers' behavioral intention. Hierarchical multiple regression was performed to examine the moderating effect of gender.FindingsThe findings of this research revealed that physical appearance, general health, enjoyment, affiliation and condition have positive influences on consumers' behavioral intention, while privacy risk and security risk exert negative impact on consumers' behavioral intention. More importantly, the moderating results indicated that only affiliation, privacy risk and security risk have stronger influences on female, while other predictors showed the same effects on both genders.Practical implicationsFitness providers should embrace health and fitness apps as a new contactless tool to offer services during and after the COVID-19-related lockdown. Fitness providers and app developers need to focus more on the utility and quality of their health and fitness apps. In addition, they should add more gamification elements to health and fitness apps because these elements could increase consumers' hedonic experience especially during the lockdown. Third, the security systems in health and fitness apps should be continuously updated to decline privacy risk during and after the COVID-19-related lockdown. Lastly, when female consumers are targeted during the lockdown, fitness providers should make more efforts to imbue health and fitness apps with more social features and improve the level of security.Originality/valueAlthough the importance of contactless technologies has been highlighted ever since the beginning of the COVID-19 pandemic, there has been very little research on the usage of health and fitness apps during the lockdown based on TCV and TPR. Meanwhile, the moderating role of gender differences in this context remains underexplored. This research is one of the early attempts to fill in these gaps. The findings of this study will enhance the theoretical framework regarding the acceptance and use of health and fitness apps;it also challenges the generalizability of SHT in the context of the COVID-19-related lockdown. Moreover, several important implications for the health and fitness industry during and after the COVID-19 pandemic were suggested.

10.
Chemosensors ; 11(2):152, 2023.
Article in English | ProQuest Central | ID: covidwho-2289018

ABSTRACT

Horseradish peroxidase (HRP) combined with its fluorescence substrates is attracting increasing attention for biochemical analysis. Amplex red is the most widely used fluorescence substrate to HRP;however, it suffers from some drawbacks, such as nonspecific responsiveness toward carboxylesterases. Discovering a new small molecular fluorescence substrate with improved sensitivity and selectivity for HRP is thus desired. Herein, three dihydrofluorescein derivatives (DCFHs) are presented to serve as HRP substrates through fluorescence turn-on methods. The most promising one, 2,7-dichloro-9-(2-(hydroxymethyl)phenyl)-9H-xanthene-3,6-diol (DCFH-1), exhibited excellent sensitivity in the detection of HRP. Moreover, DCFH-1 does not respond to carboxylesterase, thus holding advantages over Amplex red. In the further study, the detection reagent in the commercial ELISA kits was replaced with DCFH-1 to establish a new fluorescence ELISA, which works very well in the quantification of inflammatory cytokine biomarkers from in vitro models.

11.
Front Psychol ; 14: 1101353, 2023.
Article in English | MEDLINE | ID: covidwho-2252027

ABSTRACT

In March 2020, COVID-19 brought illness, lockdowns, and economic turmoil worldwide. Studies from March-April 2020 reported increased psychological distress, especially among younger (vs. older) adults. Here, we examine whether age differences persisted in a 29-wave longitudinal survey conducted with an American national life-span sample over the first 16 months of the pandemic. Socio-emotional selectivity theory (SST) predicts that older age will be consistently associated with lower psychological distress due to life-span changes in motivation, while the strength and vulnerability integration model (SAVI) posits that age differences in psychological distress will diminish under prolonged stress. We find that younger adults consistently reported more psychological distress than older adults, though age differences did decrease over time. Prior diagnosis with anxiety or depression additionally predicted greater psychological distress throughout the study, but did not moderate age differences. We discuss implications for psychological theories of aging and interventions to reduce psychological distress.

12.
Antibiotiki i Khimioterapiya ; 67(45208):35-41, 2022.
Article in Russian | EMBASE | ID: covidwho-2242020

ABSTRACT

Interferons (IFN) have antiviral activity against many viruses, including SARS-CoV-2. A combination of IFN-a2b and the antioxidant taurine is widely used in the Russian Federation, and its antiviral activity has not been studied before. The aim of this study was to determine the antiviral activity of interferon drugs, in combination with taurine and without it. The study included cytotoxicity and antiviral activity assays of IFN-a2b preparations, when stored according to the instructions at 2-8°C, and after 1 month storage at the temperature of 20-26°C in a pre-opened state. The combination of IFN alpha-2b with taurine has a higher antiviral activity compared to IFN alpha-2b mono-preparation by more than 25% at a «low» and 85% at a «high» multiplicity of infection. Selectivity index for combinations of IFN-a2b (50,000 IU/dose) + taurine (1 mg/ml) and IFN-a2b (10,000 IU/ml) + taurine (0.8 mg/ml) was more than 600 units, whereas for the IFN-a2b (10,000 IU/ml) it was 200 units. Antiviral activity does not change after one month at room temperature. The combination of interferon with taurine at high concentrations was less toxic than interferon. The results obtained demonstrate practicability of interferon alpha-2b and taurine combination use for treatment and prevention of COVID-19.

13.
Chembiochem ; 24(9): e202200801, 2023 05 02.
Article in English | MEDLINE | ID: covidwho-2242957

ABSTRACT

Messenger RNA (mRNA) is being used as part of an emerging class of biotherapeutics with great promise for preventing and treating a wide range of diseases, as well as encoding programmable nucleases for genome editing. However, mRNA's low stability and immunogenicity, as well as the impermeability of the cell membrane to mRNA greatly limit mRNA's potential for therapeutic use. Lipid nanoparticles (LNPs) are currently one of the most extensively studied nanocarriers for mRNA delivery and have recently been clinically approved for developing mRNA-based vaccines to prevent COVID-19. In this review, we summarize the latest advances in designing ionizable lipids and formulating LNPs for intracellular and tissue-targeted mRNA delivery. Furthermore, we discuss the progress of intracellular mRNA delivery for spatiotemporally controlled CRISPR/Cas9 genome editing by using LNPs. Finally, we provide a perspective on the future of LNP-based mRNA delivery for CRISPR/Cas9 genome editing and the treatment of genetic disorders.


Subject(s)
COVID-19 , Nanoparticles , Humans , Gene Editing , CRISPR-Cas Systems/genetics , Gene Transfer Techniques , RNA, Messenger/genetics , COVID-19/genetics
14.
Adv Sci (Weinh) ; : e2201853, 2022 Nov 23.
Article in English | MEDLINE | ID: covidwho-2238320

ABSTRACT

Glycans are ubiquitously expressed sugars, coating the cell and protein surfaces. They are found on many proteins as either short and branched chains or long chains sticking out from special membrane proteins, known as proteoglycans. This sugar cushion, the glycocalyx, modulates specific interactions and protects the cell. Here it is shown that both the expression of proteoglycans and the glycans expressed on the surface of both the host and virus proteins have a critical role in modulating viral attachment to the cell. A mathematical model using SARS-Cov-2 as an archetypical virus to study the glycan role during infection is proposed. It is shown that this occurs via a tug-of-war of forces. On one side, the multivalent molecular recognition that viral proteins have toward specific host glycans and receptors. On the other side, the glycan steric repulsion that a virus must overcome to approach such specific receptors. By balancing both interactions, viral tropism can be predicted. In other words, the authors can map out the cells susceptible to virus infection in terms of receptors and proteoglycans compositions.

15.
Res Aging ; : 1640275221105231, 2022 May 30.
Article in English | MEDLINE | ID: covidwho-2240417

ABSTRACT

This study aimed to understand whether older adults not only received but also provided help during the first COVID-19 lockdown in Belgium, which factors motivated them to help, and whether older adults differed from younger age groups in terms of helping behavior and motives. Bivariate analyses were performed using data generated from an online cross-sectional survey in Belgium (N = 1892).The results showed that older adults who received help also provided it. This "interdependence" - mutual or reciprocal dependence - occurred regardless of age. In terms of motives for providing help, both older adults and their younger peers were primarily motivated by present-oriented and emotion-related motivation: older people were motivated to provide help by altruistic values and humanism, and enhancement motives linked to self-development.Policy implications of these results entail: during crisis situations, make use of the bond between older adults and their neighbors, such as caring communities.

16.
Analytic Methods in Accident Research ; 38, 2023.
Article in English | Web of Science | ID: covidwho-2231280

ABSTRACT

Research in highway safety continues to struggle to address two potentially important issues;the role that unobserved factors may play on resulting crash and injury-severity likelihoods, and the issue of identification in safety modeling caused by the self-selective sampling inherent in commonly used safety data (the fact that drivers in observed crashes are not a random sample of the driving population, with riskier drivers being over-represented in crash data bases). This paper addresses unobserved heterogeneity using mixing distributions and attempts to provide insight into the potential sample-selection problem by considering data before and during the COVID-19 pandemic. Based on a survey of vehicle usage (vehicle miles traveled) and subsequent statistical modeling, there is evi-dence that riskier drivers likely made up a larger proportion of vehicle miles traveled dur-ing the pandemic than before, suggesting that the increase in injury severities observed during COVID-19 could potentially be due to the over-representation of riskier drivers in observed crash data. However, by exploring Florida crash data before and during the pan-demic (and focusing on crashes where risky behaviors were observed), the empirical anal-ysis of observed crash data suggests (using random parameters multinomial logit models of driver-injury severities with heterogeneity in means and variances) that the observed increase in injury severity during the COVID-19 pandemic (calendar year 2020) was likely due largely to fundamental changes in driver behavior and less to changes in the sample selectivity of observed crash data. The findings of this paper provide some initial guidance to future work that can begin to more rigorously explore and assess the role of selectivity and resulting identification issues that may be present when using observed crash data.(c) 2022 Elsevier Ltd. All rights reserved.

17.
Front Psychol ; 13: 1075814, 2022.
Article in English | MEDLINE | ID: covidwho-2231460

ABSTRACT

Socioemotional selectivity theory (SST) maintains that when futures loom large, as they typically do in youth, people are motivated to explore. When future time is perceived as more limited, as is typical in old age, people are motivated to pursue emotionally meaningful goals. Because the COVID-19 pandemic primed mortality across the age spectrum, it provided an opportunity to examine whether age differences in social motivation typically observed were also present during the pandemic. We measured social motivation, as operationalized by social preferences, in two studies during peak of the pandemic in 2020. Once vaccines were introduced in 2021, we conducted two additional studies using the same experimental paradigm. As hypothesized, at the peak of the pandemic, social preferences favored emotionally meaningful partners regardless of age. Social preferences differed by age (as reliably observed in research conducted before the pandemic) when vaccines were available. Findings suggest that widely documented age differences in social motivation reflect time horizons more than chronological age.

18.
J Mol Biol ; 435(2): 167891, 2022 Nov 24.
Article in English | MEDLINE | ID: covidwho-2236436

ABSTRACT

Phosphorylation of SARS-CoV-2 nucleoprotein recruits human cytosolic 14-3-3 proteins playing a well-recognized role in replication of many viruses. Here we use genetic code expansion to demonstrate that 14-3-3 binding is triggered by phosphorylation of SARS-CoV-2 nucleoprotein at either of two pseudo-repeats centered at Ser197 and Thr205. According to fluorescence anisotropy measurements, the pT205-motif,presentin SARS-CoV-2 but not in SARS-CoV, is preferred over the pS197-motif by all seven human 14-3-3 isoforms, which collectively display an unforeseen pT205/pS197 peptide binding selectivity hierarchy. Crystal structures demonstrate that pS197 and pT205 are mutually exclusive 14-3-3-binding sites, whereas SAXS and biochemical data obtained on the full protein-protein complex indicate that 14-3-3 binding occludes the Ser/Arg-rich region of the nucleoprotein, inhibiting its dephosphorylation. This Ser/Arg-rich region is highly prone to mutations, as exemplified by the Omicron and Delta variants, with our data suggesting that the strength of 14-3-3/nucleoprotein interaction can be linked with the replicative fitness of the virus.

19.
Clinical Case Studies ; 2023.
Article in English | Web of Science | ID: covidwho-2195295

ABSTRACT

We report a case with a 7-year-old girl with autism spectrum disorder and anxiety disorder who had severe restrictive eating leading to various medical concerns raised by her pediatrician. Following medical consultation and a descriptive functional assessment, a therapist implemented behavioral intervention consisting of a visual cue, choice, and differential reinforcement of alternative behaviors. The intervention was focused on both in-home meals and telehealth consultation during mealtimes, as the COVID-19 pandemic necessitated moving to remote consultation for continued treatment. The success of this study has long-standing implications for the benefits of positive feeding interventions and telehealth as well as parental training strategies.

20.
Analytic Methods in Accident Research ; : 100263, 2022.
Article in English | ScienceDirect | ID: covidwho-2158366

ABSTRACT

Research in highway safety continues to struggle to address two potentially important issues;the role that unobserved factors may play on resulting crash and injury-severity likelihoods, and the issue of identification in safety modeling caused by the self-selective sampling inherent in commonly used safety data (the fact that drivers in observed crashes are not a random sample of the driving population, with riskier drivers being over-represented in crash data bases). This paper addresses unobserved heterogeneity using mixing distributions and attempts to provide insight into the potential sample-selection problem by considering data before and during the COVID-19 pandemic. Based on a survey of vehicle usage (vehicle miles traveled) and subsequent statistical modeling, there is evidence that riskier drivers likely made up a larger proportion of vehicle miles traveled during the pandemic than before, suggesting that the increase in injury severities observed during COVID-19 could potentially be due to the over-representation of riskier drivers in observed crash data. However, by exploring Florida crash data before and during the pandemic (and focusing on crashes where risky behaviors were observed), the empirical analysis of observed crash data suggests (using random parameters multinomial logit models of driver-injury severities with heterogeneity in means and variances) that the observed increase in injury severity during the COVID-19 pandemic (calendar year 2020) was likely due largely to fundamental changes in driver behavior and less to changes in the sample selectivity of observed crash data. The findings of this paper provide some initial guidance to future work that can begin to more rigorously explore and assess the role of selectivity and resulting identification issues that may be present when using observed crash data.

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