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1.
Proc Natl Acad Sci U S A ; 120(48): e2301642120, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-37983511

RESUMO

Science is among humanity's greatest achievements, yet scientific censorship is rarely studied empirically. We explore the social, psychological, and institutional causes and consequences of scientific censorship (defined as actions aimed at obstructing particular scientific ideas from reaching an audience for reasons other than low scientific quality). Popular narratives suggest that scientific censorship is driven by authoritarian officials with dark motives, such as dogmatism and intolerance. Our analysis suggests that scientific censorship is often driven by scientists, who are primarily motivated by self-protection, benevolence toward peer scholars, and prosocial concerns for the well-being of human social groups. This perspective helps explain both recent findings on scientific censorship and recent changes to scientific institutions, such as the use of harm-based criteria to evaluate research. We discuss unknowns surrounding the consequences of censorship and provide recommendations for improving transparency and accountability in scientific decision-making to enable the exploration of these unknowns. The benefits of censorship may sometimes outweigh costs. However, until costs and benefits are examined empirically, scholars on opposing sides of ongoing debates are left to quarrel based on competing values, assumptions, and intuitions.


Assuntos
Censura Científica , Ciência , Responsabilidade Social , Custos e Análise de Custo
2.
BMC Med Educ ; 24(1): 547, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38755653

RESUMO

INTRODUCTION: Non-technical skills (NTS) including communication, teamwork, leadership, situational awareness, and decision making, are essential for enhancing surgical safety. Often perceived as tangential soft skills, NTS are many times not included in formal medical education curricula or continuing medical professional development. We aimed to explore exposure of interprofessional teams in North-Central Nigeria to NTS and ascertain perceived facilitators and barriers to interprofessional training in these skills to enhance surgical safety and inform design of a relevant contextualized curriculum. METHODS: Six health facilities characterised by high surgical volumes in Nigeria's North-Central geopolitical zone were purposively identified. Federal, state, and private university teaching hospitals, non-teaching public and private hospitals, and a not-for-profit health facility were included. A nineteen-item, web-based, cross-sectional survey was distributed to 71 surgical providers, operating room nurses, and anaesthesia providers by snowball sampling through interprofessional surgical team leads from August to November 2021. Data were analysed using Fisher's exact test, proportions, and constant comparative methods for free text responses. RESULTS: Respondents included 17 anaesthesia providers, 21 perioperative nurses, and 29 surgeons and surgical trainees, with a 95.7% survey completion rate. Over 96% had never heard of any NTS for surgery framework useful for variable resource contexts and only 8% had ever received any form of NTS training. Interprofessional teams identified communication and teamwork as the most deficient personal skills (38, 57%), and as the most needed for surgical team improvement (45, 67%). There was a very high demand for NTS training by all surgical team members (64, 96%). The main motivations for training were expectations of resultant improved patient safety and improved interprofessional team dynamics. Week-long, hybrid training courses (with combined in-person and online components) were the preferred format for delivery of NTS education. Factors that would facilitate attendance included a desire for patient safety and self-improvement, while barriers to attendance were conflicts of time, and training costs. CONCLUSIONS: Interprofessional surgical teams in the Nigerian context have a high degree of interest in NTS training, and believe it can improve team dynamics, personal performance, and ultimately patient safety. Implementation of NTS training programs should emphasize interprofessional communication and teamworking.


Assuntos
Relações Interprofissionais , Equipe de Assistência ao Paciente , Humanos , Estudos Transversais , Nigéria , Masculino , Comunicação , Liderança , Feminino , Currículo , Adulto , Inquéritos e Questionários , Competência Clínica
3.
J Am Chem Soc ; 145(44): 24175-24183, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37888947

RESUMO

The arylation of 2-alkyl aziridines by nucleophilic ring-opening or transition-metal-catalyzed cross-coupling enables facile access to biologically relevant ß-phenethylamine derivatives. However, both approaches largely favor C-C bond formation at the less-substituted carbon of the aziridine, thus enabling access to only linear products. Consequently, despite the attractive bond disconnection that it poses, the synthesis of branched arylated products from 2-alkyl aziridines has remained inaccessible. Herein, we address this long-standing challenge and report the first branched-selective cross-coupling of 2-alkyl aziridines with aryl iodides. This unique selectivity is enabled by a Ti/Ni dual-catalytic system. We demonstrate the robustness of the method by a twofold approach: an additive screening campaign to probe functional group tolerance and a feature-driven substrate scope to study the effect of the local steric and electronic profile of each coupling partner on reactivity. Furthermore, the diversity of this feature-driven substrate scope enabled the generation of predictive reactivity models that guided mechanistic understanding. Mechanistic studies demonstrated that the branched selectivity arises from a TiIII-induced radical ring-opening of the aziridine.

4.
J Am Chem Soc ; 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37014945

RESUMO

While the oxidative addition of Ni(I) to aryl iodides has been commonly proposed in catalytic methods, an in-depth mechanistic understanding of this fundamental process is still lacking. Herein, we describe a detailed mechanistic study of the oxidative addition process using electroanalytical and statistical modeling techniques. Electroanalytical techniques allowed rapid measurement of the oxidative addition rates for a diverse set of aryl iodide substrates and four classes of catalytically relevant complexes (Ni(MeBPy), Ni(MePhen), Ni(Terpy), and Ni(BPP)). With >200 experimental rate measurements, we were able to identify essential electronic and steric factors impacting the rate of oxidative addition through multivariate linear regression models. This has led to a classification of oxidative addition mechanisms, either through a three-center concerted or halogen-atom abstraction pathway based on the ligand type. A global heat map of predicted oxidative addition rates was created and shown applicable to a better understanding of the reaction outcome in a case study of a Ni-catalyzed coupling reaction.

5.
Ann Surg ; 277(6): 952-957, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35185128

RESUMO

OBJECTIVE: To determine the association between SAO workforce and mortality from emergent surgical and obstetric conditions within US HR Rs. BACKGROUND: SAO workforce per capita has been identified as a core metric of surgical capacity by the Lancet Commission on Global Surgery, but its utility has not been assessed at the subnational level for a high-income country. METHODS: The number of practicing surgeons, anesthesiologists, and obstetricians per capita was estimated for all HRRs using the US Health Resources & Services Administration Area Health Resource File Database. Deaths due to emergent general surgical and obstetric conditions were determined from the Center for Disease Control and Prevention WONDER database. We utilized B-spline quantile regression to model the relationship between SAO workforce and emergent surgical mortality at different quantiles of mortality and calculated the expected change in mortality associated with increases in SAO workforce. RESULTS: The median SAO workforce across all HRRs was 74.2 per 100,000 population (interquartile range 33.3-241.0). All HRRs met the Lancet Commission on Global Surgery lower target of 20 SAO per 100,000, and 97.7% met the upper target of 40 per 100,000. Nearly 2.8 million Americans lived in HRRs with fewer than 40 SAO per 100,000. Increases in SAO workforce were associated with decreases in surgical mortality in HRRs with high mortality, with minimal additional decreases in mortality above 60 to 80 SAO per 100,000. CONCLUSIONS: Increasing SAO workforce capacity may reduce emergent surgical and obstetric mortality in regions with high surgical mortality but diminishing returns may be seen above 60 to 80 SAO per 100,000. Trial Registration: N/A.


Assuntos
Anestesia , Anestesiologia , Cirurgiões , Feminino , Gravidez , Estados Unidos/epidemiologia , Humanos , Recursos Humanos , Anestesiologistas
6.
J Am Chem Soc ; 144(12): 5575-5582, 2022 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-35298885

RESUMO

The oxidative addition of aryl halides to bipyridine- or phenanthroline-ligated nickel(I) is a commonly proposed step in nickel catalysis. However, there is a scarcity of complexes of this type that both are well-defined and undergo oxidative addition with aryl halides, hampering organometallic studies of this process. We report the synthesis of a well-defined Ni(I) complex, [(CO2Etbpy)NiICl]4 (1). Its solution-phase speciation is characterized by a significant population of monomer and a redox equilibrium that can be perturbed by π-acceptors and σ-donors. 1 reacts readily with aryl bromides, and mechanistic studies are consistent with a pathway proceeding through an initial Ni(I) → Ni(III) oxidative addition to form a Ni(III) aryl species. Such a process was demonstrated stoichiometrically for the first time, affording a structurally characterized Ni(III) aryl complex.


Assuntos
Compostos Heterocíclicos , Níquel , Catálise , Estrutura Molecular , Oxirredução , Estresse Oxidativo
8.
J Am Chem Soc ; 142(19): 8928-8937, 2020 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-32348673

RESUMO

We previously reported the development of an electron-deficient olefin (EDO) ligand, Fro-DO, that promotes the generation of quaternary carbon centers via Ni-catalyzed Csp3-Csp3 cross-coupling with aziridines. By contrast, electronically and structurally similar EDO ligands such as dimethyl fumarate and electron-deficient styrenes afford primarily ß-hydride elimination side reactivity. Only a few catalyst systems have been identified that promote the formation of quaternary carbons via Ni-catalyzed Csp3-Csp3 cross-coupling. Although Fro-DO represents a promising ligand in this regard, the basis for its superior performance is not well understood. Here we describe a detailed mechanistic study of the aziridine cross-coupling reaction and the role of EDO ligands in facilitating Csp3-Csp3 bond formation. This analysis reveals that cross-coupling proceeds by a Ni0/II cycle with a NiII azametallacyclobutane catalyst resting state. Turnover-limiting C-C reductive elimination occurs from a spectroscopically observable NiII-dialkyl intermediate bound to the EDO. Computational analysis shows that Fro-DO accelerates turnover limiting reductive elimination via LUMO lowering. However, it is no more effective than dimethyl fumarate at reducing the barrier to Csp3-Csp3 reductive elimination. Instead, Fro-DO's unique reactivity arises from its ability to associate favorably to NiII intermediates. Natural bond order second-order perturbation theory analysis of the catalytically relevant NiII intermediate indicates that Fro-DO binds to NiII through an additional stabilizing donor-acceptor interaction between its sulfonyl group and NiII. Design of new ligands to evaluate this proposal supports this model and has led to the development of a new and tunable ligand framework.


Assuntos
Alcenos/química , Aziridinas/química , Carbono/química , Níquel/química , Catálise , Teoria da Densidade Funcional , Elétrons , Cinética , Ligantes , Estrutura Molecular
9.
Proc Natl Acad Sci U S A ; 112(17): 5360-5, 2015 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-25870272

RESUMO

National randomized experiments and validation studies were conducted on 873 tenure-track faculty (439 male, 434 female) from biology, engineering, economics, and psychology at 371 universities/colleges from 50 US states and the District of Columbia. In the main experiment, 363 faculty members evaluated narrative summaries describing hypothetical female and male applicants for tenure-track assistant professorships who shared the same lifestyle (e.g., single without children, married with children). Applicants' profiles were systematically varied to disguise identically rated scholarship; profiles were counterbalanced by gender across faculty to enable between-faculty comparisons of hiring preferences for identically qualified women versus men. Results revealed a 2:1 preference for women by faculty of both genders across both math-intensive and non-math-intensive fields, with the single exception of male economists, who showed no gender preference. Results were replicated using weighted analyses to control for national sample characteristics. In follow-up experiments, 144 faculty evaluated competing applicants with differing lifestyles (e.g., divorced mother vs. married father), and 204 faculty compared same-gender candidates with children, but differing in whether they took 1-y-parental leaves in graduate school. Women preferred divorced mothers to married fathers; men preferred mothers who took leaves to mothers who did not. In two validation studies, 35 engineering faculty provided rankings using full curricula vitae instead of narratives, and 127 faculty rated one applicant rather than choosing from a mixed-gender group; the same preference for women was shown by faculty of both genders. These results suggest it is a propitious time for women launching careers in academic science. Messages to the contrary may discourage women from applying for STEM (science, technology, engineering, mathematics) tenure-track assistant professorships.


Assuntos
Academias e Institutos , Candidatura a Emprego , Estilo de Vida , Ciência , Direitos da Mulher , Feminino , Humanos , Masculino , Fatores Sexuais , Estados Unidos
10.
J Aquat Anim Health ; 30(3): 226-232, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29845647

RESUMO

Researchers engaged in surgical implantation of acoustic transmitters into fish must receive adequate and appropriate training to ensure the welfare of their subjects and the quality of the data collected. Increasingly, researchers are being encouraged to partner with veterinarians to improve training and to consider the principles of animal welfare in training. Here, we describe a five-stage training pathway, including implementation of new training tools (the Translational Training Tools and field certification), that was developed collaboratively by researchers and veterinarians and addresses the "three Rs" of animal welfare in the context of surgical training. The three Rs include animal replacement, reduction of the number of animals used, and refinement of techniques to decrease or eliminate pain or distress. The Translational Training Tools, described in the context of the training pathway, use tools as replacement models during training to reduce the number of animals used and allow for refinement of surgical skills prior to working on live animals. The purpose of this paper is to document the Translational Training Tools and the training pathway, which will be useful in developing de novo protocols for review by Institutional Animal Care and Use Committees and similar bodies.


Assuntos
Aquicultura/educação , Peixes/cirurgia , Tecnologia de Sensoriamento Remoto/veterinária , Bem-Estar do Animal , Animais , Aquicultura/instrumentação , Aquicultura/métodos , Pesqueiros
11.
Behav Brain Sci ; 38: e137, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26785767

RESUMO

In the target article, Duarte et al. allege that the lack of political diversity reduces research efficacy. We pose a thought experiment that could provide an empirical test by examining whether institutional review board (IRB) members, granting agencies, and journal reviewers filter scientific products based on political values, invoking scientific criteria (rigor, etc.) as their justification. When these same products are cast in terms highlighting opposite values, do these people shift their decisions?


Assuntos
Comitês de Ética em Pesquisa , Pesquisa , Humanos , Psicologia , Ciência , Pensamento
12.
Proc Natl Acad Sci U S A ; 108(8): 3157-62, 2011 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-21300892

RESUMO

Explanations for women's underrepresentation in math-intensive fields of science often focus on sex discrimination in grant and manuscript reviewing, interviewing, and hiring. Claims that women scientists suffer discrimination in these arenas rest on a set of studies undergirding policies and programs aimed at remediation. More recent and robust empiricism, however, fails to support assertions of discrimination in these domains. To better understand women's underrepresentation in math-intensive fields and its causes, we reprise claims of discrimination and their evidentiary bases. Based on a review of the past 20 y of data, we suggest that some of these claims are no longer valid and, if uncritically accepted as current causes of women's lack of progress, can delay or prevent understanding of contemporary determinants of women's underrepresentation. We conclude that differential gendered outcomes in the real world result from differences in resources attributable to choices, whether free or constrained, and that such choices could be influenced and better informed through education if resources were so directed. Thus, the ongoing focus on sex discrimination in reviewing, interviewing, and hiring represents costly, misplaced effort: Society is engaged in the present in solving problems of the past, rather than in addressing meaningful limitations deterring women's participation in science, technology, engineering, and mathematics careers today. Addressing today's causes of underrepresentation requires focusing on education and policy changes that will make institutions responsive to differing biological realities of the sexes. Finally, we suggest potential avenues of intervention to increase gender fairness that accord with current, as opposed to historical, findings.


Assuntos
Preconceito , Ciência , Mulheres , Feminino , Humanos , Matemática , Recursos Humanos
13.
Artigo em Inglês | MEDLINE | ID: mdl-38565310

RESUMO

Helicobacter spp. infections in mice can have broad-ranging effects on gastrointestinal, reproductive, and immune systems. This can introduce significant confounding variables for research and may reduce scientific rigor. Screening mouse colonies for Helicobacter species can be accomplished via noninvasive PCR testing on filter paper placed in animal-free dirty bedding sentinel cages. In our facility, one tablespoon of dirty bedding from each cage on a rack is added to a designated sentinel cage every 3 wk at cage change, and PCR testing is performed on in-cage filter paper quarterly. We hypothesized that cages that received Helicobacter spp.-positive bedding at later time points would have a lower detection rate of Helicobacter spp. with PCR testing compared with cages that received positive bedding at earlier time points due to the filter paper becoming saturated. To determine if screening would be able to detect one positive row of cages on a rack, 9 tablespoons of Helicobacter-positive bedding and 71 tablespoons of negative bedding were added at the 3-, 6-, or 9-wk time points to 14 empty sentinel cages per time point. Negative bedding was added every 3 wk to cages not scheduled to receive positive bedding. Negative controls received 80 tablespoons of negative bedding and positive controls received 80 tablespoons of positive bedding at each time point. Filter paper was tested via PCR for Helicobacter spp. at 12 wk. All positive controls tested positive, and all negative controls tested negative. Two 3-wk cages, two 6-wk cages, and three 9-wk cages were positive, indicating no difference between time points. This resulted in a 16.7% Helicobacter spp. detection rate. These results indicate that PCR on in-cage filter paper may not be reliable in detecting low levels of Helicobacter spp. nucleic acid in dirty bedding.

14.
Artigo em Inglês | MEDLINE | ID: mdl-38428928

RESUMO

The use of soiled-bedded sentinels (SBSs) has historically been the standard for colony health surveillance monitoring at our institution. With the advent of newer technologies in which dust collected from filters is tested by PCR, we compared traditional SBS with PCR testing of both exhaust air dust collected from a filter in the downstream vertical plenum (exhaust dust test [EDT]) and the SBS cage-level exhaust filter (SCEF). Our hypothesis was that both methods of filter testing would identify more pathogens than SBS testing. Twenty-five individually ventilated mouse racks that used disposable caging were sanitized and placed into rotation. Rack plenums were tested by PCR to verify negative results before the study start. Exhaust dust collection media were placed in the exhaust plenum (n = 25). SBS cages were placed on each side of the rack with 2 mice per cage (n = 42 mice), with the remaining cage slots occupied by research animals. At each triweekly cage change, the exhaust air filters were carefully removed from the cage top, placed in sterile 50-mL conical tubes, and pooled for submission. After 3 mo, the SBS mice were tested via serology for bacterial and viral agents and by PCR for Helicobacter species, pinworms, and ectoparasites. In addition, the EDT filter and SCEF were collected for PCR to evaluate for the same agents. Our results indicate that the SCEF consistently detected agents more frequently than the EDT filter placed in the plenum and that the EDT filter media detected agents more frequently than did the SBS mice. Our data suggest that both PCR methods of detection are superior to SBS for individually ventilated disposable rodent cages and that the SCEF is superior to EDT. These data supported our movement of institution toward environmental monitoring as a method of rodent colony health surveillance.

15.
Artigo em Inglês | MEDLINE | ID: mdl-38500774

RESUMO

Objective: On 4 March 2022, the first community-acquired case of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was reported in Vanuatu, with community transmission occurring subsequently. It was expected that the number of notified SARS-CoV-2 cases would be an underestimate of the true infection rate of this outbreak; however, the magnitude of underreporting was unknown. The purpose of this study was to provide a population-based estimate of SARS-CoV-2 infection shortly after the first reports of community transmission, to understand the level of underdetection and undernotification in Vanuatu and thus to inform ongoing prevention and response activities. Methods: We conducted a cross-sectional SARS-CoV-2 prevalence study in two geographical administrative areas in Port Vila, Vanuatu in April 2022. All residents in selected areas were eligible. Trained teams conducted demographic and behavioural interviews and collected nasal specimens. Specimens were tested by polymerase chain reaction. The primary outcomes were the rates of SARS-CoV-2 attack (point prevalence) and cumulative attack, underdetection, notification and household secondary attack. Results: A total of 252 people from 84 households participated. Among 175 people who had a sample collected, 91 were SARS-CoV-2-positive (attack rate 52.0%). Most cases had not been detected before the study (underdetection rate 91.5%). More than half of previously detected cases were notified (notification rate 65.2%). Discussion: Within the first few weeks of community transmission, more than half of participants in the selected areas had evidence of SARS-CoV-2 infection; however, most infections had been undetected. This study provides important information about the rapid spread of novel infectious diseases in Vanuatu.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/diagnóstico , COVID-19/epidemiologia , Incidência , Vanuatu , Estudos Transversais
16.
Perspect Psychol Sci ; : 17456916241252085, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38752984

RESUMO

We identify points of conflict and consensus regarding (a) controversial empirical claims and (b) normative preferences for how controversial scholarship-and scholars-should be treated. In 2021, we conducted qualitative interviews (n = 41) to generate a quantitative survey (N = 470) of U.S. psychology professors' beliefs and values. Professors strongly disagreed on the truth status of 10 candidate taboo conclusions: For each conclusion, some professors reported 100% certainty in its veracity and others 100% certainty in its falsehood. Professors more confident in the truth of the taboo conclusions reported more self-censorship, a pattern that could bias perceived scientific consensus regarding the inaccuracy of controversial conclusions. Almost all professors worried about social sanctions if they were to express their own empirical beliefs. Tenured professors reported as much self-censorship and as much fear of consequences as untenured professors, including fear of getting fired. Most professors opposed suppressing scholarship and punishing peers on the basis of moral concerns about research conclusions and reported contempt for peers who petition to retract papers on moral grounds. Younger, more left-leaning, and female faculty were generally more opposed to controversial scholarship. These results do not resolve empirical or normative disagreements among psychology professors, but they may provide an empirical context for their discussion.

17.
Psychol Sci Public Interest ; 24(1): 15-73, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37098793

RESUMO

We synthesized the vast, contradictory scholarly literature on gender bias in academic science from 2000 to 2020. In the most prestigious journals and media outlets, which influence many people's opinions about sexism, bias is frequently portrayed as an omnipresent factor limiting women's progress in the tenure-track academy. Claims and counterclaims regarding the presence or absence of sexism span a range of evaluation contexts. Our approach relied on a combination of meta-analysis and analytic dissection. We evaluated the empirical evidence for gender bias in six key contexts in the tenure-track academy: (a) tenure-track hiring, (b) grant funding, (c) teaching ratings, (d) journal acceptances, (e) salaries, and (f) recommendation letters. We also explored the gender gap in a seventh area, journal productivity, because it can moderate bias in other contexts. We focused on these specific domains, in which sexism has most often been alleged to be pervasive, because they represent important types of evaluation, and the extensive research corpus within these domains provides sufficient quantitative data for comprehensive analysis. Contrary to the omnipresent claims of sexism in these domains appearing in top journals and the media, our findings show that tenure-track women are at parity with tenure-track men in three domains (grant funding, journal acceptances, and recommendation letters) and are advantaged over men in a fourth domain (hiring). For teaching ratings and salaries, we found evidence of bias against women; although gender gaps in salary were much smaller than often claimed, they were nevertheless concerning. Even in the four domains in which we failed to find evidence of sexism disadvantaging women, we nevertheless acknowledge that broad societal structural factors may still impede women's advancement in academic science. Given the substantial resources directed toward reducing gender bias in academic science, it is imperative to develop a clear understanding of when and where such efforts are justified and of how resources can best be directed to mitigate sexism when and where it exists.


Assuntos
Salários e Benefícios , Sexismo , Humanos , Masculino , Feminino , Atitude , Academias e Institutos
18.
J Am Assoc Lab Anim Sci ; 62(6): 487-493, 2023 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-37802606

RESUMO

Training personnel to work with animals presents a variety of challenges, both logistically and with regard to animal welfare. These issues make training an ideal opportunity to evaluate practices and to implement the 3R principles (refinement, replacement, and reduction). Cardiac blood collection from mice is a procedure that can compromise the 3Rs by requiring repeated practice and animal euthanasia. The development of a non-animal training model would promote the 3R principles. Our goals for the development of a new training model for cardiac blood collection from mice were to reduce the number of mice needed to achieve competency, improve our culture of care, and refine the training approach by improving competency. The training model was developed using commonly available materials. The total cost of the model was less than $15 USD per model. Two training curricula were conducted concurrently over a 5-mo period: 1) a curriculum in which trainees used the model before progressing to live mice and 2) the traditional curriculum, which used euthanized mice throughout. The measured variables included the total number of mice used, proportions of trainees who reached competency, the time needed to reach competency, method comprehension, quality of skill performance, trainer and trainee feedback, and training costs. The alternative group used at least 10 fewer mice per technician as compared with the traditionally trained group. The alternative group had a higher competency rate, with 82% (9 of 11 trainees) reaching competency compared with 60% (3 of 5 trainees) in the traditional group. Skill comprehension and quality were superior in the alternative group, as evidenced by fewer gross lesions at necropsy. Overall, personnel in the alternative group provided positive feedback with regard to the use of fewer mice, acquisition of both skill and confidence, and benefits for compassion fatigue. The use of this model is now our standard approach for training personnel in cardiac blood collection in mice. Our results demonstrate that the use of models in training curricula can enhance skill development and reduce the use of mice.


Assuntos
Bem-Estar do Animal , Currículo , Animais , Camundongos , Competência Clínica , Eutanásia Animal
19.
Tissue Eng Part C Methods ; 29(7): 307-320, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37335050

RESUMO

Regenerative medicine approaches to restore the mandibular condyle of the temporomandibular joint (TMJ) may fill an unmet patient need. In this study, a method to implant an acellular regenerative TMJ prosthesis was developed for orthotopic implantation in a pilot goat study. The scaffold incorporated a porous, polycaprolactone-hydroxyapatite (PCL-HAp, 20wt% HAp) 3D printed condyle with a cartilage-matrix-containing hydrogel. A series of material characterizations was used to determine the structure, fluid transport, and mechanical properties of 3D printed PCL-HAp. To promote marrow uptake for cell seeding, a scaffold pore size of 152 ± 68 µm resulted in a whole blood transport initial velocity of 3.7 ± 1.2 mm·s-1 transported to the full 1 cm height. The Young's modulus of PCL was increased by 67% with the addition of HAp, resulting in a stiffness of 269 ± 20 MPa for etched PCL-HAp. In addition, the bending modulus increased by 2.06-fold with the addition of HAp to 470 MPa for PCL-HAp. The prosthesis design with an integrated hydrogel was compared with unoperated contralateral control and no-hydrogel group in a goat model for 6 months. A guide was used to make the condylectomy cut, and the TMJ disc was preserved. MicroCT assessment of bone suggested variable tissue responses with some regions of bone growth and loss, although more loss may have been exhibited by the hydrogel group than the no-hydrogel group. A benchtop load transmission test suggested that the prosthesis was not shielding load to the underlying bone. Although variable, signs of neocartilage formation were exhibited by Alcian blue and collagen II staining on the anterior, functional surface of the condyle. Overall, this study demonstrated signs of functional TMJ restoration with an acellular prosthesis. There were apparent limitations to continuous, reproducible bone formation, and stratified zonal cartilage regeneration. Future work may refine the prosthesis design for a regenerative TMJ prosthesis amenable to clinical translation.


Assuntos
Articulação Temporomandibular , Alicerces Teciduais , Animais , Alicerces Teciduais/química , Articulação Temporomandibular/diagnóstico por imagem , Osso e Ossos , Disco da Articulação Temporomandibular , Cabras , Engenharia Tecidual/métodos
20.
Lab Anim ; 56(5): 482-489, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35603540

RESUMO

Consideration of The Three R's (Replacement, Reduction, and Refinement) is essential when setting Humane Endpoints; however, a common interpretation assumes that Humane Endpoints are timepoints to perform euthanasia. This interpretation is not always consistent with the three Rs. There are many available intervention options that - when used to respond to pain, discomfort, or distress - facilitate application of the three Rs while achieving experimental goals. At our institution, the term 'Humane Endpoints' was replaced with 'Humane Intervention Points', to ensure responses beyond euthanasia are given priority by laboratory animal professionals and researchers. Identification of Humane Intervention Points in the research protocol provides us with a more accurate reflection of the measures used to alleviate pain and distress in animals used for research, testing, and teaching - an outcome easily envisioned elsewhere.Points d'intervention humains (PIH): Affinage de la terminologie d'évaluation finale pour intégrer des options d'intervention sans recours à l'euthanasie afin d'améliorer le bien-être des animaux et de préserver les résultats expérimentaux Résumé.


Assuntos
Bem-Estar do Animal , Animais , Eutanásia Animal
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