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Girls and women face persistent negative stereotyping within STEM (science, technology, engineering, mathematics). This field intervention was designed to improve boys' perceptions of girls' STEM ability. Boys (N = 667; mostly White and East Asian) aged 9-15 years in Canadian STEM summer camps (2017-2019) had an intervention or control conversation with trained camp staff. The intervention was a multi-stage persuasive appeal: a values affirmation, an illustration of girls' ability in STEM, a personalized anecdote, and reflection. Control participants discussed general camp experiences. Boys who received the intervention (vs. control) had more positive perceptions of girls' STEM ability, d = 0.23, an effect stronger among younger boys. These findings highlight the importance of engaging elementary-school-aged boys to make STEM climates more inclusive.
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Instituciones Académicas , Estereotipo , Masculino , Humanos , Femenino , Niño , CanadáRESUMEN
INTRODUCTION: Women continue to be underrepresented in Science, Technology, Engineering, and Mathematics (STEM) and research suggests that academic-gender stereotypes can be a contributing factor. In the present research, we examined whether adolescent daughters' and their parents' gender stereotypes about math and liberal arts would predict the academic orientation of daughters at a critical time of career related decision-making. METHODS: Participants included girls in late adolescence (N = 185, Mage = 17) and at least one parent (N = 230, Mage = 49), resulting in 147 mother-daughter dyads and 83 father-daughter dyads. Implicit academic-gender stereotypes were measured using an Implicit Association Test (IAT) and explicit stereotypes, academic attitudes, academic ability, and daughters' intentions to pursue a degree in STEM were measured using self-reports. RESULTS: Neither mothers' nor fathers' implicit or explicit academic-gender stereotypes predicted adolescent daughters' implicit stereotypes; however, fathers' explicit stereotypes predicted daughters' explicit stereotypes. In addition, daughters' academic orientation, a latent variable composed of adolescent girls' academic attitudes, academic ability, and intentions to pursue a degree in STEM, was predicted by daughters' own implicit and explicit stereotypes. This was the case for relative orientation toward math versus liberal arts, as well as math (but not liberal arts) orientation. CONCLUSIONS: These findings suggest the importance of challenging academic-gender stereotypes during adolescence and suggest that at this stage in development, mothers' and fathers' academic stereotypes might have limited relation to daughters' own implicit associations with academic domains.
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Intención , Núcleo Familiar , Adolescente , Actitud , Humanos , Matemática , Padres , TecnologíaRESUMEN
The goal of this research was to examine children's implicit racial attitudes. Across three studies, a total of 359 White 5- to 12-year-olds completed child-friendly exemplar (Affective Priming Task; Affect Misattribution Procedure) and category-based (Implicit Association Test) implicit measures of racial attitudes. Younger children (5- to 8-year-olds) showed automatic ingroup positivity toward White child exemplars, whereas older children (9- to 12-year-olds) did not. Children also showed no evidence of automatic negativity toward Black exemplars, despite demonstrating consistent pro-White versus Black bias on the category-based measure. Together, the results suggest that (a) implicit ingroup and outgroup attitudes can follow distinct developmental trajectories, and (b) the spontaneous activation of implicit intergroup attitudes can depend on the salience of race.
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Actitud , Racismo/psicología , Población Blanca/psicología , Negro o Afroamericano , Niño , Desarrollo Infantil/fisiología , Preescolar , Femenino , Humanos , Masculino , Ontario/etnologíaRESUMEN
Initial theory and research examining children's implicit racial attitudes suggest that an implicit preference favoring socially advantaged groups emerges early in childhood and remains stable across development (Dunham, Baron, & Banaji, 2008). In two studies, we examined the ubiquity of this theory by measuring non-Black minority and non-White majority children's implicit racial attitudes toward White and Black racial outgroups in two distinct cultural contexts. In Study 1, non-Black minority children in an urban North American community with a large Black population showed an implicit pro-White (versus Black) bias in early childhood. Contrary to previous findings, the magnitude of this bias was lower among older children. In Study 2, Malay (majority) and Chinese (minority) children and adults in the Southeast Asian country of Brunei, with limited contact with White or Black peers, showed an implicit pro-White (versus Black) bias in early childhood. However, the magnitude of bias was greater for adults. Together, these findings support initial theorizing about the early development of implicit intergroup cognition, but suggest that context may affect these biases across development to a greater extent than was previously thought. A video abstract of this article can be viewed at: https://www.youtube.com/watch?v=vgQP8e4MSCk&feature=youtu.be.
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Actitud , Comparación Transcultural , Racismo/psicología , Adulto , Factores de Edad , Niño , Desarrollo Infantil , Etnicidad/psicología , Humanos , Estados Unidos , Adulto JovenRESUMEN
Studies with adults suggest that implicit preferences favoring White versus Black individuals can be reduced through exposure to positive Black exemplars. However, it remains unclear whether developmental differences exist in the capacity for these biases to be changed. This study included 369 children and examined whether their implicit racial bias would be reduced following exposure to positive Black exemplars. Results showed that children's implicit pro-White bias was reduced following exposure to positive Black exemplars, but only for older children (Mage = ~10 years). Younger children's (Mage = ~7 years) implicit bias was not affected by this intervention. These results suggest developmental differences in the malleability of implicit racial biases and point to possible age differences in intervention effectiveness.
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Desarrollo Infantil , Racismo/psicología , Percepción Social , Factores de Edad , Niño , Preescolar , Femenino , Humanos , MasculinoRESUMEN
BACKGROUND: To extend our knowledge of general strain theory by exploring how under-researched strains such as racial discrimination, witnessing violence, physical victimization and verbal bullying affect adolescent substance use while considering differences according to racial identification. METHODS: This research utilized data from wave three of the Project on Human Development in Chicago Neighborhoods. Statistical analysis was primarily composed of path analysis using full information maximum likelihood parameter estimates. RESULTS: The findings reveal that reporting fear decreased alcohol and marijuana use among adolescents and that racial discrimination, witnessing violence, and being the victim of verbal bullying indirectly affected marijuana and alcohol use through fear. No support was found for depression as a mediating variable. Physical victimization was the only social strain that had a direct positive effect on marijuana and alcohol use but only for Hispanics and African Americans. CONCLUSIONS: The results suggest that strains may be operating differently and there may be differential levels of exposure to certain strains according to one's race.
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Miedo , Adolescente , Consumo de Bebidas Alcohólicas , Cannabis , Chicago , Humanos , RacismoRESUMEN
Male-female variations in health-behavior continue to be of national and international significance with men generally being more likely to be engaged in behaviors that enhance risk across an array of preventable diseases and injuries as well as premature deaths. The literature has identified non-medical use of prescription drugs (NMUPD) as a developing and particularly dangerous substance use behavior among college students. The literature has reported sex differences (male; female) in NMUPD but has yet to explain how gender-orientation (e.g., masculine, feminine) might impact NMUPD. The purpose of this study is to address this gap by examining the influence of gender-orientation on NMUPD. Using survey data collected during the 2013-2014 academic year from a convenience sample of college students at a mid-sized Midwestern university, we examine the association of gender-orientation with NMUPD (N=796). To do this, we separate masculine and feminine scales from the BEM Sex Role Inventory and use logistic regression to test whether masculine or feminine gender characteristics influence the likelihood of NMUPD (lifetime measure of any use and by category). This analysis shows that self-identified characteristics associated with masculinity increase the odds of NMUPD while femininity is associated with lower odds of NMUPD. Findings from this study increase our knowledge of gender-orientation and sex interactions as factors that might influence NMUPD thus demonstrating the importance of differentiating sex from gender-orientation.
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BACKGROUND: Clostridium difficile is a primary cause of antibiotic-associated diarrhea that typically develops when gut microbiota is altered. Conventional treatment for C. difficile infection (CDI) is additional antimicrobial administration, which further disrupts normal intestinal microbiota, often resulting in poor treatment outcomes. METHODS: A pregnant dairy cow was repeatedly immunized with recombinant mutants of toxins A and B produced by C. difficile, and the resultant hyperimmune bovine colostrum (HBC) was evaluated for therapeutic efficacy in gnotobiotic piglets with diarrhea due to CDI. Control piglets received nonimmune colostrum. To determine the impact of HBC on gut microbiota, 1 of 2 groups of piglets transplanted with normal human gut microbiota was treated with HBC. RESULTS: Nonimmune colostrum-treated piglets developed moderate to severe diarrhea and colitis. In contrast, HBC-treated piglets had mild or no diarrhea and mild or no colitis. Lyophilization had no detectable impact on HBC efficacy. HBC had no discernible effect on the composition of normal human gut microbiota in the porcine intestinal tract. CONCLUSIONS: HBC provides an oral, cost-effective, and safe alternative to antibiotic therapy for CDI. By preserving intestinal microbiota, HBC may be more efficacious than antibiotics. Additional studies are warranted to establish HBC as a viable immunotherapeutic agent for human use against CDI.
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Clostridioides difficile/inmunología , Infecciones por Clostridium/inmunología , Infecciones por Clostridium/terapia , Calostro/inmunología , Anciano , Animales , Antibacterianos/inmunología , Bovinos , Colitis/inmunología , Colitis/microbiología , Colitis/terapia , Diarrea/inmunología , Diarrea/microbiología , Femenino , Humanos , Factores Inmunológicos/inmunología , Enfermedades Intestinales/inmunología , Intestinos/inmunología , Intestinos/microbiología , Masculino , Persona de Mediana Edad , Embarazo , PorcinosRESUMEN
BACKGROUND: Intensified food production, i.e. agricultural intensification and industrialized livestock operations may have adverse effects on human health and promote disease emergence via numerous mechanisms resulting in either direct impacts on humans or indirect impacts related to animal and environmental health. For example, while biodiversity is intentionally decreased in intensive food production systems, the consequential decrease in resilience in these systems may in turn bear increased health risks. However, quantifying these risks remains challenging, even if individual intensification measures are examined separately. Yet, this is an urgent task, especially in rapidly developing areas of the world with few regulations on intensification measures, such as in the Greater Mekong Subregion (GMS). METHODS: We systematically searched the databases PubMed and Scopus for recent studies conducted on the association between agricultural (irrigation, fertilization, pesticide application) and livestock (feed additives, animal crowding) intensification measures and human health risks in the GMS. The search terms used were iteratively modified to maximize the number of retrieved studies with relevant quantitative data. RESULTS: We found that alarmingly little research has been done in this regard, considering the level of environmental contamination with pesticides, livestock infection with antibiotic resistant pathogens and disease vector proliferation in irrigated agroecosystems reported in the retrieved studies. In addition, each of the studies identified focused on specific aspects of intensified food production and there have been no efforts to consolidate the health risks from the simultaneous exposures to the range of hazardous chemicals utilized. CONCLUSIONS: While some of the studies identified already reported environmental contamination bearing considerable health risks for local people, at the current state of research the actual consolidated risk from regional intensification measures cannot be estimated. Efforts in this area of research need to be rapidly and considerably scaled up, keeping pace with the current level of regional intensification and the speed of pesticide and drug distribution to facilitate the development of agriculture related policies for regional health promotion.
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Agricultura , Contaminantes Ambientales/toxicidad , Sustancias Peligrosas/toxicidad , Salud Laboral , Salud Pública , Asia Sudoriental , HumanosRESUMEN
BACKGROUND: A dramatic increase in morbidity and mortality from Clostridium difficile infection (CDI) due to the recent emergence of virulent, antibiotic-resistant strains has led to a search for alternatives to antibiotics, including vaccines and immune-based therapy that target the 2 key toxins-TcdA and TcdB. METHODS: We investigated the efficacy of specific human monoclonal antibodies (HuMab) and alpaca polyclonal antibodies against each toxin separately and in combination in the gnotobiotic piglet model of CDI. Additionally, the HuMab and polyclonal antibodies were exploited to investigate the precise contribution of each toxin to systemic and/or gastrointestinal (GI) tract disease. RESULTS: Our results indicate that TcdB is an important virulence factor associated with GI and systemic pathology. Administration of anti-TcdB antibody alone or with anti-TcdA protected 100% of piglets from development of systemic CDI and minimized GI lesions. Conversely, 100% of piglets administered only anti-TcdA developed severe GI and systemic disease, with 67%-83% fatality, faring worse than placebo-treated control animals. CONCLUSIONS: These results highlight the importance of TcdB in the pathogenesis of CDI and the effectiveness of TcdB-specific antibody in treating CDI. However, the results raise new questions regarding the nature of TcdA interaction with therapeutic antibodies.
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Anticuerpos Antibacterianos/uso terapéutico , Anticuerpos Monoclonales Humanizados/inmunología , Proteínas Bacterianas/inmunología , Toxinas Bacterianas/inmunología , Clostridioides difficile/patogenicidad , Infecciones por Clostridium/prevención & control , Enterocolitis Seudomembranosa/inmunología , Enterocolitis Seudomembranosa/prevención & control , Enterotoxinas/inmunología , Animales , Anticuerpos Antibacterianos/administración & dosificación , Anticuerpos Antibacterianos/inmunología , Anticuerpos Monoclonales Humanizados/administración & dosificación , Clostridioides difficile/inmunología , Infecciones por Clostridium/inmunología , Tracto Gastrointestinal/inmunología , Tracto Gastrointestinal/patología , Vida Libre de Gérmenes , Humanos , PorcinosRESUMEN
Multicomponent interpenetrating polymer network (mIPN) hydrogels are promising tissue-engineering scaffolds that could closely resemble key characteristics of native tissues. The mechanical and biochemical properties of mIPNs can be finely controlled to mimic key features of target cellular microenvironments, regulating cell-matrix interactions. In this work, we fabricated hydrogels made of collagen type I (Col I), fibrin, hyaluronic acid (HA), and poly (ethylene glycol) diacrylate (PEGDA) using a network-by-network fabrication approach. With these mIPNs, we aimed to develop a biomaterial platform that supports the in vitro culture of human astrocytes and potentially serves to assess the effects of the abnormal deposition of fibrin in cortex tissue and simulate key aspects in the progression of neuroinflammation typically found in human pathologies such as Alzheimer's disease (AD), Parkinson's disease (PD), and tissue trauma. Our resulting hydrogels closely resembled the complex modulus of AD human brain cortex tissue (~7.35 kPa), promoting cell spreading while allowing for the modulation of fibrin and hyaluronic acid levels. The individual networks and their microarchitecture were evaluated using confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). Human astrocytes were encapsulated in mIPNs, and negligible cytotoxicity was observed 24 h after the cell encapsulation.
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Using data from 15 countries, this article investigates whether descriptive and prescriptive gender norms concerning housework and child care (domestic work) changed after the onset of the COVID-19 pandemic. Results of a total of 8,343 participants (M = 19.95, SD = 1.68) from two comparable student samples suggest that descriptive norms about unpaid domestic work have been affected by the pandemic, with individuals seeing mothers' relative to fathers' share of housework and child care as even larger. Moderation analyses revealed that the effect of the pandemic on descriptive norms about child care decreased with countries' increasing levels of gender equality; countries with stronger gender inequality showed a larger difference between pre- and post-pandemic. This study documents a shift in descriptive norms and discusses implications for gender equality-emphasizing the importance of addressing the additional challenges that mothers face during health-related crises.
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The novel antibiotic MBX-500, dosed at 100, 200, or 400 mg/kg twice daily for 7 days, was evaluated for the treatment of Clostridium difficile infection (CDI) in the gnotobiotic pig model. MBX-500 increased survival at all doses and at high doses improved clinical signs and reduced lesion severity, similar to vancomycin. Our results show that MBX-500 is an effective antibiotic for the treatment of diarrhea associated with CDI and prevents severe systemic disease.
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Antibacterianos/farmacología , Clostridioides difficile/patogenicidad , Infecciones por Clostridium/tratamiento farmacológico , Diarrea/tratamiento farmacológico , Fluoroquinolonas/farmacología , Pirimidinonas/farmacología , Animales , Colon/microbiología , Colon/patología , Diarrea/microbiología , Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos , Vida Libre de Gérmenes , Estimación de Kaplan-Meier , Índice de Severidad de la Enfermedad , Porcinos , Resultado del Tratamiento , Vancomicina/farmacologíaRESUMEN
BACKGROUND: Clostridium difficile infection (CDI) can cause a wide range of disease, from mild diarrhea to fulminant systemic disease. The incidence of systemic CDI with fatal consequence has increased rapidly in recent years. METHODS: Using an ultrasensitive cytotoxicity assay, we measured C. difficile toxin A (TcdA) and C. difficile toxin B (TcdB) in sera and body fluids of piglets and mice exposed to C. difficile to investigate the relationship between the presence of toxins in body fluids and systemic manifestations of CDI. RESULTS: We found that both TcdA and TcdB disseminate systemically, with toxins present in the sera and body fluids of infected animals, and toxemia is significantly correlated with the development of systemic CDI. The systemic administration of neutralizing antibodies against both toxins blocked the development of systemic disease in mice. We measured cytokine concentrations in the sera of mice and piglets with systemic and nonsystemic CDI and found that proinflammatory mediators were considerably elevated in animals with systemic CDI. CONCLUSION: Our study demonstrates the existence of a strong correlation between toxemia and the occurrence of systemic disease, supporting the hypothesis that systemic CDI is most likely due to the toxicity of TcdA and TcdB and the induction of proinflammatory cytokines by the toxins.
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Proteínas Bacterianas/toxicidad , Toxinas Bacterianas/toxicidad , Clostridioides difficile/patogenicidad , Infecciones por Clostridium/mortalidad , Enterotoxinas/toxicidad , Toxemia/mortalidad , Animales , Anticuerpos Neutralizantes/administración & dosificación , Anticuerpos Neutralizantes/inmunología , Antitoxinas/administración & dosificación , Antitoxinas/inmunología , Proteínas Bacterianas/análisis , Proteínas Bacterianas/sangre , Toxinas Bacterianas/análisis , Toxinas Bacterianas/sangre , Líquidos Corporales/química , Supervivencia Celular/efectos de los fármacos , Infecciones por Clostridium/complicaciones , Citocinas/sangre , Técnicas Citológicas/métodos , Modelos Animales de Enfermedad , Enterotoxinas/análisis , Enterotoxinas/sangre , Ratones , Ratones Endogámicos C57BL , PorcinosRESUMEN
In the current research we examined non-Black children's associations with targets who differed by both race and gender, with a focus on the role of categorization in informing children's biases. Children aged 5 to 12 years (N = 206; 109 boys, 97 girls; 55% White; 68% of household incomes > $75,000/year), recruited from a science museum in a large multicultural Canadian city, completed a child-friendly Implicit Association Test (IAT; Greenwald et al., 2003) that included own-gender Black and other-gender White targets. Children were randomly assigned to complete this IAT under one of three categorization conditions. When asked to categorize targets by gender as opposed to race, both girls and boys showed relatively more positive associations with own-gender Black targets over other-gender White targets. Children in a third, Ambiguous-Categorization (AC-IAT; Lipman et al., 2021) condition, which allowed for categorization by gender and/or race, were more likely to spontaneously categorize additional final trials primarily by gender (70%), suggesting that gender was the more salient social category. However, girls' and boys' biases in this condition differed, with girls showing relatively more positive associations with own-gender Black targets (Black girls > White boys) and boys showing relatively more positive associations with other-gender White targets (White girls > Black boys). In addition, the more boys and girls categorized by gender (over race) at the end of the task, the more they showed positive associations with own-gender Black targets over other-gender White targets. These findings provide insight into children's social categorization processes and biases toward targets who differ by race and gender. (PsycInfo Database Record (c) 2023 APA, all rights reserved).
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Actitud , Identidad de Género , Masculino , Femenino , Humanos , CanadáRESUMEN
The goal of the current research was to gain an understanding of people's mental representations of an apologetic face. In Study 1, participants' responses were used to generate visual templates of apologetic faces through reverse correlation (Study 1a, n = 121), and a new set of participants (Study 1b, n = 37 and 1c, n = 153) rated that image (group-level Classification Image, CI), as well as either the inverse image (group-level anti-CI in Study 1b) or base face (in Study 1c), on apology-related characteristics. Results demonstrated that people have a mental representation of an apologetic face, and that sadness is an important feature of this template. To examine similarities between mental representations of apologetic and sad faces, participants in Study 2 generated visual templates of sad faces using reverse correlation (Study 2a, n = 121). New participants (Study 2b, n = 162) were then randomly assigned to rate the averaged face, eyes, and mouths (group-level CIs) as well as the individual visual templates (individual-level CIs) generated from both studies for either how apologetic or sad they appeared. Visual templates of apologetic and sad faces were seen as apologetic, providing evidence of the prominence of sadness in mental representations of apology. Supplementary Information: The online version contains supplementary material available at 10.1007/s10919-022-00422-5.
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There is considerable interest in MnOHx moieties, particularly in the stepwise changes in those O-H bonds in tandem with Mn oxidation state changes. The reactivity of aquo-derived ligands, {MOHx}, is also heavily influenced by the electronic character of the other ligands. Despite the prevalence of oxygen coordination in biological systems, preparation of mononuclear Mn complexes of this type with all O-donors is rare. Herein, we report several Mn complexes with perfluoropinacolate (pinF)2- including the first example of a crystallographically characterized mononuclear {Mn(iii)OH} with all O-donors, K2[Mn(OH)(pinF)2], 3. Complex 3 is prepared via deprotonation of K[Mn(OH2)(pinF)2], 1, the pKa of which is estimated to be 18.3 ± 0.3. Cyclic voltammetry reveals quasi-reversible redox behavior for both 1 and 3 with an unusually large ΔEp, assigned to the Mn(iii/ii) couple. Using the Bordwell method, the bond dissociation free energy (BDFE) of the O-H bond in {Mn(ii)-OH2} is estimated to be 67-70 kcal mol-1. Complex 3 abstracts H-atoms from 1,2-diphenylhydrazine, 2,4,6-TTBP, and TEMPOH, the latter of which supports a PCET mechanism. Under basic conditions in air, the synthesis of 1 results in K2[Mn(OAc)(pinF)2], 2, proposed to result from the oxidation of Et2O to EtOAc by a reactive Mn species, followed by ester hydrolysis. Complex 3 alone does not react with Et2O, but addition of O2 at low temperature effects the formation of a new chromophore proposed to be a Mn(iv) species. The related complexes K(18C6)[Mn(iii)(pinF)2], 4, and (Me4N)2[Mn(ii)(pinF)2], 5, have also been prepared and their properties discussed in relation to complexes 1-3.
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The repair of neuronal tissue is a challenging process due to the limited proliferative capacity of neurons. Neural stem cells (NSCs) can aid in the regeneration process of neural tissue due to their high proliferation potential and capacity to differentiate into neurons. The therapeutic potential of these cells can only be achieved if sufficient cells are obtained without losing their differentiation potential. Toward this end, an astrocyte-derived coating (HAc) was evaluated as a promising substrate to promote the proliferation of NSCs. Mass spectroscopy and scanning electron microscopy were used to characterize the HAc. The proliferation rate and the expression of stemness and differentiation markers in NSCs cultured on the HAc were evaluated and compared to the responses of these cells to commonly used coating materials including Poly-L-Ornithine (PLO), and a Human Induced Pluripotent Stem Cell (HiPSC)-based coating. The use of the HAc promotes the in vitro cell growth of NSCs. The expression of the stemness markers Sox2 and Nestin, and the differentiation marker DCX in the HAc group was akin to the expression of these markers in the controls. In summary, HAc supported the proliferation of NSCs while maintaining their stemness and neural differentiation potential.
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We examined the piglet model of Clostridium difficile illness (CDI) in humans, because swine are naturally susceptible to C. difficile. The piglet is a reproducible model of acute or chronic CDI with characteristic pseudomembranous colitis. Germ-free piglets were consistently and extensively colonized after oral challenge with the human strain 027/BI/NAP1, establishing an infectious dose-age relationship. This allowed a demarcation between acute fatal and chronic models. The clinical manifestations of disease inclusive of gastrointestinal and systemic symptoms and characteristic mucosal lesions of the large bowel (including pseudomembranous colitis) are described. Additionally, we demonstrate the presence of toxins in feces, body fluids, and serum and a significant elevation in interleukin 8 levels in animals with severe disease. We conclude that piglets infected with C. difficile mimic many of the key characteristics observed in humans with CDI and are suitable animals in which to investigate the role played by virulence attributes, drug efficacy, and vaccine candidates.
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Clostridioides difficile/patogenicidad , Enterocolitis Seudomembranosa/microbiología , Enfermedad Aguda , Animales , Enfermedad Crónica , Modelos Animales de Enfermedad , Vida Libre de Gérmenes , PorcinosRESUMEN
Background: In randomized controlled trials, attrition rates often differ by treatment status, jeopardizing causal inference. Inverse probability weighting methods and estimation of treatment effect bounds have been used to adjust for this bias. Objectives: We compare the performance of various methods within two samples, both generated through lottery-based randomization: one with considerable differential attrition and an augmented dataset with less problematic attrition. Research Design: We assess the performance of various correction methods within the dataset with problematic attrition. In addition, we conduct simulation analyses. Results: Within the more problematic dataset, we find the correction methods often performed poorly. Simulation analyses indicate that deviations from the underlying assumptions for bounding approaches damage the performance of estimated bounds. Conclusions: We recommend the verification of the underlying assumptions in attrition correction methods whenever possible and, when verification is not possible, using these methods with caution.