Social commerce facilitates conversations among buyers across the world and enhances eWOM sharing. This paper investigates the key roles of online shoppers' culture (collectivism vs. individualism) ...and past experience as drivers of engagement with brand-related information sharing. Based on the theory of planned behavior (TPB) and consumer culture theory (CCT), a conceptual framework was developed and tested empirically. Data collected from a representative sample of online shoppers (N = 559) was analyzed using Structural Equation Modeling. Findings reveal that shoppers' experience is indirectly related to brand-related information sharing, and mediated by three TPB beliefs (attitude, subjective norms and perceived behavior control). These relationships were moderated by customer culture. The impact of attitude on information sharing was greater for collectivist shoppers, whereas the influence of subjective norms was stronger for individualist shoppers. Theoretical contributions and practical implications are discussed.
Online retailers have acknowledged the efficacy of leveraging electronic Word of Mouth (eWOM) sharing on social media as a promotional tactic that significantly affects consumers' purchasing ...decisions. Grounded in agency theory, this research delves into the behaviors of individuals who participate in eWOM dissemination. It investigates the mediating role of individuals' self-perception as the originator (Self as Source, SAS) on their reactions to sharing eWOM content. Additionally, the study scrutinizes the impact of consumer engagement and the moderating role of incentive acceptance on this process. The results of two studies reveal dual routes through which purchase intention can be affected: a direct route and an indirect route that is mediated by SAS perception and consumer engagement. Moreover, the results support a moderated mediation model wherein the acceptance of incentives moderates the mediation process through consumer engagement. Theoretical and practical implications are discussed.
Meiotic chromosomal pairing is facilitated by a conserved cytoskeletal organization. Telomeres associate with perinuclear microtubules via Sun/KASH complexes on the nuclear envelope (NE) and dynein. ...Telomere sliding on perinuclear microtubules contributes to chromosome homology searches and is essential for meiosis. Telomeres ultimately cluster on the NE, facing the centrosome, in a configuration called the chromosomal bouquet. Here, we discuss novel components and functions of the bouquet microtubule organizing center (MTOC) in meiosis, but also broadly in gamete development. The cellular mechanics of chromosome movements and the bouquet MTOC dynamics are striking. The newly identified zygotene cilium mechanically anchors the bouquet centrosome and completes the bouquet MTOC machinery in zebrafish and mice. We hypothesize that various centrosome anchoring strategies evolved in different species. Evidence suggests that the bouquet MTOC machinery is a cellular organizer, linking meiotic mechanisms with gamete development and morphogenesis. We highlight this cytoskeletal organization as a new platform for creating a holistic understanding of early gametogenesis, with direct implications to fertility and reproduction.
The strategy of inviting online shoppers to negotiate product prices has been employed by numerous online sellers due to its benefits for buyers and sellers. Social media facilitates sharing ...information regarding such economic benefits among shoppers, thereby generating eWOM, which boosts online social commerce. Yet not all buyers choose to embrace sellers' offers to negotiate product price. In the current paper, we employ consumer culture theory and the elaboration likelihood model to theorize the effects of culture and involvement on consumer engagement in price negotiation. Two studies were designed to test the proposed conceptual framework. Based on eBay transaction data (N = 498), Study 1 supported the hypothesized positive main effects of collectivism and involvement on shoppers' engagement in price negotiation. Study 2 demonstrated, in a controlled laboratory setting (N = 468), the moderating effect of eWOM on these relationships. When other buyers shared information regarding price negotiation, the positive effect of collectivism on negotiation was mitigated, and the effect of involvement was strengthened. These findings have significant theoretical, practical, and social implications.
Patients with chronic lymphocytic leukemia (CLL) have a suboptimal humoral response to vaccination. Recently, BNT162b2, an mRNA COVID-19 vaccine with a high efficacy of 95% in immunocompetent ...individuals, was introduced. We investigated the safety and efficacy of the BNT162b2 mRNA COVID-19 vaccine in patients with CLL from nine medical centers in Israel, Overall 400 patients were included, of whom 373 were found to be eligible for the analysis of antibody response. The vaccine appeared to be safe and only grade 1-2 adverse events were seen in 50% of the patients. Following the second dose, an antibody response was detected in 43% of the cohort. Among these CLL patients, 61% of the treatment-na ve patients responded to the vaccine, while responses developed in only 18% of those with ongoing disease, 37% of those previously treated with a BTK inhibitor and 5% of those recently given an anti-CD20 antibody. Among patients treated with BCL2 as monotherapy or in combination with anti-CD20, 62% and 14%, respectively, developed an immune response. There was a high concordance between neutralizing antibodies and positive serological response to spike protein. Based on our findings we developed a simple seven-factor score including timing of any treatment with anti-CD20, age, treatment status, and IgG, IgA, IgM and hemoglobin levels. The sum of all the above parameters can serve as a possible estimate to predict whether a given CLL patient will develop sufficient antibodies. In conclusion, the BNT162b2 mRNA COVID-19 vaccine was found to be safe in patients with CLL, but its efficacy is limited, particularly in treated patients.
Summary
The immunogenicity and safety of Pfizer‐BioNTech BNT162b2 mRNA vaccine in allogeneic haematopoietic stem cell transplantation (HSCT) recipients are unknown. We prospectively followed 152 HSCT ...recipients who were at least six months following transplantation and with no active acute graft‐versus‐host disease (GVHD). Blood samples were taken 2–4 weeks after the second vaccination and analyzed for receptor‐binding domain (RBD) antibodies and neutralizing antibodies (NA). 272 immunocompetent healthcare workers served as controls. At a median of 28 days after the second vaccination, 118 patients (77·6%) developed RBD immunoglobulin G (IgG) with a geometric mean titre (GMT) of 2·61 95% CI (confidence interval), 2·16–3·16. In the control group 269/272 (98·9%) developed RBD IgG, with a GMT of 5·98 (95% CI 5·70–6·28), P < 0·0001. The GMT of NA in HSCT recipients and controls was 116·0 (95% CI 76·5–175·9), and 427·9 (95% CI 354·3–516·7) respectively (P < 0001). Multivariate logistic regression analysis revealed that HSCT recipients with no chronic GVHD and no immunosuppressive therapy at the time of vaccination had significantly higher levels of NA following the second vaccination. Adverse events were minimal and were less common than in healthy controls. In conclusion; the BNT162b2 mRNA vaccination is safe and effective in HSCT recipients, especially those who are immunosuppression‐free. A significant fraction developed protecting NA.
The BNT162b2 messenger RNA (mRNA) vaccine against severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) has been shown to be safe and effective in immunocompetent patients. The safety and ...efficacy of this vaccine in liver transplantation (LT) recipients is still under evaluation. The objective of this study was to assess the safety and efficacy of the BNT162b2 vaccine among transplant recipients. The immune responses of 76 LT recipients receiving 2 doses of the vaccine were compared with those of 174 age‐matched immunocompetent controls. Postvaccination immunoglobulin G (IgG) antibodies against the receptor‐binding domain (RBD) of SARS‐CoV‐2 and neutralizing antibodies (NA) to the BNT162b2 mRNA vaccine were determined at least 14 days after the second dose of the vaccine. IgG antibody titers ≥1.1 were defined as positive antibodies. Adverse effects were monitored during the study period. Following administration of the second dose, transplant recipients showed reduced immune responses compared with controls (72% versus 94.2%; P < 0.001). At a median time of 38 days after the second vaccination, the geometric mean of RBD IgG and NA titers were 2.1 (95% confidence interval CI, 1.6‐2.6) and 150 (95% CI, 96‐234) among transplant recipients and 4.6 (95% CI, 4.1‐5.1) and 429 (95% CI, 350‐528) in the control group, respectively (P < 0.001). Antibody responses were lower in transplant recipients who were receiving combined immunosuppression therapy and in those with impaired renal function. Among the LT recipients with negative antibody responses, 1 became infected with SARS‐CoV‐2, but no recipients with positive antibody responses became infected. Overall, most (n = 39 51%) adverse effects self‐reported by transplant recipients were mild and occurred more often in women than in men. Compared with patients who were immunocompetent, LT recipients had lower immune responses. The durability of immune responses to the BNT162b2 vaccine among LT recipients requires further investigation.
Social network sites (SNS) facilitate eWOM communication among consumers of different cultures. Building on contact theory and the theory of planned behavior, we propose a conceptual framework that ...integrates intercultural factors as predictors of minority consumers’ engagement with eWOM communicated by and to individuals of the dominant culture on social media. A partial least squares (PLS) analysis on data collected from the Israeli-Arab minority shows that intercultural factors (i.e., acculturation, social interaction, and language proficiency) are antecedents of minority consumer engagement with eWOM. However, this relationship is mediated by consumer beliefs (attitudes, subjective norms, and perceived behavioral control) concerning this behavior, and moderated by the cultural distance between minority and dominant culture consumers. The findings help marketers plan marketing communications that engage audiences meaningfully and generate positive eWOM when targeting ethnic-cultural minorities. The current study contributes to our understanding of minority consumers’ engagement with eWOM communicated by and to members of the hegemonic culture. It further contributes to consumer engagement theory and acculturation research by supporting the post-assimilationist view. The proposed model is highly valuable in light of the importance of the concept of consumer engagement in marketing research.
Data on the safety and efficacy of SARS-CoV-2 vaccines in immunocompromised populations are sparse.
We conducted a prospective study of 77 heart transplant (HT) recipients vaccinated with two doses ...of BNT162b2 vaccine and monitored for adverse events following both doses, the receptor-binding domain (RBD) IgG response, and neutralizing antibodies.
BNT162b2 vaccination was associated with a low rate of adverse events, characterized mostly by pain at the injection site. By a mean 41 days post second dose there were no clinical episodes of rejection, as suggested by a troponin leak or allograft dysfunction. At a mean 21 days following the second dose, IgG anti-RBD antibodies were detectable in 14 (18%) HT recipients. Immune sera neutralized SARS-CoV-2 pseudo-virus in 8 (57%) of those with IgG anti-RBD antibodies. Immunosuppressive regimen containing mycophenolic acid was associated with lower odds of an antibody response (OR = 0.12, p = 0.042).
Whether a longer time-frame for observation of an antibody response is required after vaccination in immunosuppressed individuals remains unknown.
The immunogenicity and safety of the Pfizer-BioNTech BNT162b2 mRNA vaccine in people living with human immunodeficiency virus type 1 (PLWH) are unknown. We aimed to assess the immunogenicity and ...safety of this vaccine in PLWH.
In this prospective open study, we enrolled 143 PLWH, aged ≥18 years, who attended our clinic and 261 immunocompetent health-care workers (HCWs). Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) receptor binding domain (RBD) IgG and neutralizing antibodies were measured. Adverse events, viral load and CD4 cell counts were monitored.
At a median of 18 days (interquartile range 14–21 days) after the second dose, anti-RBD-IgG was positive in 139/141 (98%) PLWH. Among HCWs, 258/261 (98.9%) developed anti-RBD-IgG at a median of 26 days (interquartile range 24–27 days) after the second dose. Following the second dose, immune sera neutralized SARS-CoV-2 pseudo-virus in 97% and 98% of PLWH and HCWs, respectively. Adverse events were reported in 60% of PLWH, mainly pain at the injection site, fatigue and headache. AIDS-related adverse events were not reported. Human immunodeficiency virus load increased in 3/143 (2%) patients from <40 copies/mL to ≤100 copies/mL. CD4+ T-cell count decreased from a geometric mean of 700 cells/μL (95% CI 648–757 cells/μL) to 633.8 cells/μL (95% CI 588–683 cells/μL) (p < 0.01).
BNT162b2 mRNA vaccine appears immunogenic and safe in PLWH who are on antiretroviral therapy with unsuppressed CD4 count and suppressed viral load.
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