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IgM and IgD B cell receptors differentially respond to endogenous antigens and control B cell fate.
Naive B cells co-express two BCR isotypes, IgM and IgD, with identical antigen-binding domains but distinct constant regions. IgM but not IgD is downregulated on autoreactive B cells. Because these isotypes are presumed to be redundant, it is unknown how this could impose tolerance. We introduced the Nur77-eGFP reporter of BCR signaling into mice that express each BCR isotype alone. Despite signaling strongly in vitro, IgD is less sensitive than IgM to endogenous antigen in vivo and developmental fate decisions are skewed accordingly. IgD-only Lyn-/- B cells cannot generate autoantibodies and short-lived plasma cells (SLPCs) in vivo, a fate thought to be driven by intense BCR signaling induced by endogenous antigens. Similarly, IgD-only B cells generate normal germinal center, but impaired IgG1+ SLPC responses to T-dependent immunization. We propose a role for IgD in maintaining the quiescence of autoreactive B cells and restricting their differentiation into autoantibody secreting cells
The influence of cultural similarity and individual factors on visitation
This paper examined how Chinese, German and American individuals’ perceptions of cultural similarity/difference influence intentions to travel to New Zealand, a novel long-haul destination. The relationship was examined along with a set of potentially influential individual difference variables, including international travel experience, uncertainty avoidance, novelty seeking and ethnocentrism. Cultural similarity was a common positive predictor of travel intentions toward New Zealand across all three countries. Respondent’s travel experience and novelty seeking were also important positive influences for this long-haul destination, at least for Americans and Germans. Respondent’s level of uncertainty avoidance was only
significant for Germany, where those with higher uncertainty were less likely to intend to visit New Zealand. Ethnocentrism was not a significant predictor in any country. These findings suggest that the perception of cultural similarity, which can be influenced by marketing campaigns, has a positive influence on travel intentions.
Tourism marketers should stress elements of cultural similarity in their campaigns, especially for those markets where there may be lower levels of knowledge about the destination
First Nations First: First Nations public servants, the future of the Australian public service workforce
This article imagines a future public service that is culturally safe and supportive of First Nations employees and end users, a place wheretransformative policy can emerge. The authors, First Nations and settler/non-indigenous academics and public servants, offer visions for change in five key areas, drawing on our academic research and public service practice
Epitope-based vaccination against pneumonic tularemia
Francisella tularensis, the etiological agent of tularemia, is one of the most infectious bacterial pathogens known. No vaccine is currently approved for public use. Previously, we identified epitopes recognized specifically by T cells obtained from individuals following infection with F. tularensis. Here, we report that a subunit vaccine constructed based upon these epitopes elicited protective immunity in “humanized” HLA class II (DRB1*0401) transgenic mice. Vaccinated mice challenged intratracheally with a lethal dose of F. tularensis (Live Vaccine Strain) exhibited a rapid increase in pro-inflammatory cytokine production and diminished number of organisms in the lungs, and a concurrent increased rate of survival. These results demonstrate the efficacy of an epitope-based tularemia vaccine and suggest that such an approach might be widely applicable to the development of vaccines specific for intracellular bacterial pathogens
Implementing a male‐specific ART counselling curriculum: a quality assessment with healthcare workers in Malawi
IntroductionThere is little HIV counselling that directly meets the needs of men in Eastern and Southern Africa, limiting men's knowledge about the benefits of HIV treatment and how to overcome barriers to engagement, contributing to poorer HIV-related outcomes than women. Male-specific approaches are needed to improve men's outcomes but may be difficult for healthcare workers (HCWs) to implement with fidelity and quality in low-resource settings. We developed a male-specific counselling curriculum which was implemented by male HCWs and then conducted a mixed-methods quality assessment.MethodsWe audio-recorded counselling sessions to assess the quality of implementation (n = 50) by male HCWs from two cadres (nurse, n = 10 and lay cadre, n = 10) and conducted focus group discussions (FGDs) with HCWs at 6 and 9 months after rollout to understand barriers and facilitators to implementation. Counselling sessions and FGDs were translated, transcribed and analysed using thematic analysis adapted from WHO Quality Counselling Guidelines. We assessed if sessions were respectful, informative, interactive, motivating and included tailored action plans for overcoming barriers to care. All data were collected September 2021-June 2022.ResultsAll sessions used respectful, non-judgemental language. Sessions were highly interactive with most HCWs frequently asking open-ended questions (n = 46, 92%) and often incorporating motivational explanations of how antiretroviral therapy contributes to life goals (n = 42, 84%). Few sessions included individually tailored action plans for clients to overcome barriers to care (n = 9, 18%). New counselling themes were well covered; however, occasionally themes of self-compassion and safe sex were not covered during sessions (n = 16 and n = 11). HCWs believed that having male HCWs conduct counselling, ongoing professional development and keeping detailed counselling notes facilitated quality implementation. Perceived barriers included curriculum length and client hesitancy to participate in action plan development. Findings were similar across cadres.ConclusionsImplementing high-quality male-specific counselling using male nurses and/or lay cadre is feasible. Efforts to utilize lay cadres should be prioritized, particularly in low-resource settings. Programmes should provide comprehensive job aids to support HCWs. Ongoing training and professional development are needed to (1) improve HCWs' skills in tailored action plans, and (2) sensitize HCWs to the need for self-compassion within male clients to promote holistic sexual health
Impact of tailored falls prevention education for older adults at hospital discharge on engagement in falls prevention strategies postdischarge: Protocol for a process evaluation
Introduction: Older adults recently discharged from hospital have greater incidence of adverse events, functional decline, falls and subsequent readmission. Providing education to hospitalised patients on how to prevent falls at home could reduce postdischarge falls. There has been limited research investigating how older adults respond to tailored falls prevention education provided at hospital discharge. The aim of this study is to evaluate how providing tailored falls prevention education to older patients at the point of, and immediately after hospital discharge in addition to usual care, affects engagement in falls prevention strategies in the 6-months postdischarge period, including their capability and motivation to engage in falls prevention strategies.
Methods and analyses: This prospective observational cohort study is a process evaluation of a randomized controlled trial, using an embedded mixed-method design. Participants (n=390) who have been enrolled in the trial are over the age of 60 years, scoring greater than 7/10 on the Abbreviated Mental Test Score. Participants are being discharged from hospital rehabilitation wards in Perth, Western Australia, and followed up for 6 months postdischarge. Primary outcome measures for the process evaluation are engagement in falls prevention strategies, including exercise, home modifications and receiving assistance with activities of daily living. Secondary outcomes will measure capability, motivation and opportunity to engage in falls prevention strategies, based on the constructs of the Capability Opportunity Motivation Behaviour system. Quantitative data are collected at baseline, then at 6 months postdischarge using structured phone interviews. Qualitative data are collected from a purposive sample of the cohort, using semistructured in-depth phone interviews. Quantitative data will be analysed using regression modelling and qualitative data will be analysed using interpretive phenomenological analysis.
Ethics and dissemination: Results will be presented in peer-reviewed journals and at conferences worldwide. This study is approved by hospital and university Human Research Ethics Committees
Phenotypic and functional characteristics of highly differentiated CD57 +NKG2C + NK cells in HIV-1- infected individuals
Natural killer (NK) cells are important anti-viral effector cells. The function and phenotype of the NK cells that constitute an individual’s NK cell repertoire can be influenced by ongoing and/or previous viral infections. Indeed, infection with human cytomegalovirus (HCMV) drives the expansion of a highly differentiated NK cell population characterized by expression of CD57 and the activating NKG2C receptor. This NK cell population has also been noted to occur in HIV-1-infected individuals. We evaluated the NK cells of HIV-1-infected and –uninfected individuals to determine the relative frequency of highly differentiated CD57 +NKG2C + NK cells and characterize these cells for their receptor expression and responsiveness to diverse stimuli. Highly differentiated CD57 +NKG2C + NK cells occurred at higher frequencies in HCMV-infected donors relative to HCMV-uninfected donors and were dramatically expanded in HIV-1/HCMV co-infected donors. The expanded CD57 +NKG2C + NK cell population in HIV-1-infected donors remained stable following antiretroviral therapy. CD57 +NKG2C + NK cells derived from HIV-1-infected individuals were robustly activated by antibody-dependent stimuli that contained anti-HIV-1 antibodies or therapeutic anti-CD20 antibody, and these NK cells mediated cytolysis through NKG2C. Lastly, CD57 +NKG2C + NK cells from HIV-1-infected donors were characterized by reduced expression of the inhibitory NKG2A receptor. The abundance of highly functional CD57 +NKG2C + NK cells in HIV-1-infected individuals raises the possibility that these NK cells could play a role in HIV-1 pathogenesis or serve as effector cells for therapeutic/cure strategies
Defective Fas expression exacerbates neurotoxicity in a model of Parkinson's disease
Fas (CD95), a member of the tumor necrosis factor-receptor superfamily, has been studied extensively as a death-inducing receptor in the immune system. However, Fas is also widely expressed in a number of other tissues, including in neurons. Here, we report that defects in the Fas/Fas ligand system unexpectedly render mice highly susceptible to neural degeneration in a model of Parkinson's disease. We found that Fas-deficient lymphoproliferative mice develop a dramatic phenotype resembling clinical Parkinson's disease, characterized by extensive nigrostriatal degeneration accompanied by tremor, hypokinesia, and loss of motor coordination, when treated with the neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) at a dose that causes no neural degeneration or behavioral impairment in WT mice. Mice with generalized lymphoproliferative disease, which express a mutated Fas ligand, display an intermediate phenotype between that of lymphoproliferative and WT mice. Moreover, Fas engagement directly protects neuronal cells from MPTP/1-methyl-4-phenylpyridinium ion toxicity in vitro. Our data show that decreased Fas expression renders dopaminergic neurons highly susceptible to degeneration in response to a Parkinson-causing neurotoxin. These findings constitute the first evidence for a neuroprotective role for Fas in vivo
The association between infant salivary cortisol and parental presence in the neonatal intensive care unit during and after COVID-19 visitation restrictions: A cross-sectional study
Objectives: Parent-infant interaction in the neonatal intensive care unit (NICU) promotes health and reduces
infant stress. During the COVID-19 pandemic, however, NICUs restricted parent-infant interaction to reduce viral
transmission. This study examined the potential relationship between pandemic visitation restrictions, parental
presence and infant stress as measured by salivary cortisol.
Methods: A two-NICU cross-sectional study of infants with gestational age (GA) 23–41 weeks, both during (n =
34) and after (n = 38) visitation restrictions. We analysed parental presence with and without visitation restrictions. The relationship between infant salivary cortisol and self-reported parental NICU presence in hours per
day was analysed using Pearson's r. A linear regression analysis included potential confounders, including GA
and proxies for infant morbidity. The unstandardised B coefficient described the expected change in logtransformed salivary cortisol per unit change in each predictor variable.
Results: Included infants had a mean (standard deviation) GA of 31(5) weeks. Both maternal and paternal NICU
presence was lower with versus without visitation restrictions (both p ≤0.05).
Log-transformed infant salivary cortisol correlated negatively with hours of parental presence (r = − 0.40, p =
.01). In the linear regression, GA (B = -0.03, p = .02) and central venous lines (B = 0.23, p = .04) contributed to
the variance in salivary cortisol in addition to parental presence (B = -0.04 p = .04).
Conclusion: COVID-19–related visitation restrictions reduced NICU parent-infant interaction and may have
increased infant stress. Low GA and central venous lines were associated with higher salivary cortisol. The
interaction between immaturity, morbidity and parental presence was not within the scope of this study and
merits further investigation
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