Time-resolved fate mapping identifies the intestinal upper crypt zone as an origin of Lgr5+ crypt base columnar cells.

In the prevailing model, Lgr5+ cells are the only intestinal stem cells (ISCs) that sustain homeostatic epithelial regeneration by upward migration of progeny through elusive upper crypt transit-amplifying (TA) intermediates. Here, we identify a proliferative upper crypt population marked by Fgfbp1, in the location of putative TA cells, that is transcriptionally distinct from Lgr5+ cells. Using a kinetic reporter for time-resolved fate mapping and Fgfbp1-CreERT2 lineage tracing, we establish that Fgfbp1+ cells are multi-potent and give rise to Lgr5+ cells, consistent with their ISC function. Fgfbp1+ cells also sustain epithelial regeneration following Lgr5+ cell depletion. We demonstrate that FGFBP1, produced by the upper crypt cells, is an essential factor for crypt proliferation and epithelial homeostasis. Our findings support a model in which tissue regeneration originates from upper crypt Fgfbp1+ cells that generate progeny propagating bi-directionally along the crypt-villus axis and serve as a source of Lgr5+ cells in the crypt base.

Is time really of the essence? Timeliness of narrative feedback in ophthalmology CBME assessments.

PURPOSE: Competency-based medical education relies on a strong program of assessment, and quality comments play a vital role in ensuring its success. The goal of this study is to determine the effect of the timeliness of assessment completion on the quality of the feedback. MATERIALS AND METHODS: Using the Quality of Assessment for Learning (QuAL) score 2478 assessments were evaluated. The assessments included those completed between July 2017 and December 2020 for 18 ophthalmology residents. Spearman correlation, Mann-Whitney U and Kruskal-Wallis tests were used to assess variations in QuAL scores based on the timeliness of assessment completion. RESULTS: The timeliness of assessment completion ranged from 0 to 299 d with the mean time for completion being 3 d. As the delay increased, the QuAL score decreased. Feedback provided 4, 5, and 14 d post-encounter demonstrated statistically significant differences in the QuAL score. Additionally, there was a significant difference in the timeliness of feedback when there is no written comment. CONCLUSIONS: This study demonstrates that the timeliness of assessment completion might have an effect on the quality of written feedback. Written feedback should be completed within 14 d of the encounter to optimize quantity and quality.

Gluten induces rapid reprogramming of natural memory αß and γδ intraepithelial T cells to induce cytotoxicity in celiac disease.

Celiac disease (CD) is an autoimmune disease in which intestinal inflammation is induced by dietary gluten. The means through which gluten-specific CD4+ T cell activation culminates in intraepithelial T cell (T-IEL)-mediated intestinal damage remain unclear. Here, we performed multiplexed single-cell analysis of intestinal and gluten-induced peripheral blood T cells from patients in different CD states and healthy controls. Untreated, active, and potential CD were associated with an enrichment of activated intestinal T cell populations, including CD4+ follicular T helper (TFH) cells, regulatory T cells (Tregs), and natural CD8+ αß and γδ T-IELs. Natural CD8+ αß and γδ T-IELs expressing activating natural killer cell receptors (NKRs) exhibited a distinct TCR repertoire in CD and persisted in patients on a gluten-free diet without intestinal inflammation. Our data further show that NKR-expressing cytotoxic cells, which appear to mediate intestinal damage in CD, arise from a distinct NKR-expressing memory population of T-IELs. After gluten ingestion, both αß and γδ T cell clones from this memory population of T-IELs circulated systemically along with gluten-specific CD4+ T cells and assumed a cytotoxic and activating NKR-expressing phenotype. Collectively, these findings suggest that cytotoxic T cells in CD are rapidly mobilized in parallel with gluten-specific CD4+ T cells after gluten ingestion.

Systematic review of simulation-based education in strabismus assessment and management.

BACKGROUND: Strabismus is a dynamic condition for which simulation-based training is valuable, given the variable complexity and relatively reduced exposure compared with other ophthalmic presentations. This study assessed the performance of simulation models available for medical training in the assessment and management of strabismus. METHODS: A systematic review of relevant peer-reviewed academic databases was conducted, without publication date restrictions. English-language publications evaluating the performance of simulation models for education on strabismus were included. Risk of bias was assessed using the Cochrane RoB-2 tool and CLARITY Risk of Bias Instrument for Cross-Sectional Surveys of Attitudes and Practices. Validity of evidence was evaluated using the Kirkpatrick framework. RESULTS: Of the total 3,298 citations exported for title and abstract screening, 54 advanced to full-text screening, and 7 were included in final review. Model types were either dry (2), wet (4), or virtual reality (1). All models were deemed to be successful, but few standardized parameters were specified. Costs of models ranged from a few dollars (ball and wood), to moderate (non-cadaveric), to costly (virtual reality). All studies scored a moderate or high risk of bias, and the majority (4/7) of studies scored level 1 on the Kirkpatrick scale. CONCLUSIONS: Research on simulation for strabismus assessment and management is limited and varied for model fidelity and testing audiences. All models were deemed individually successful compared to non-simulation-based teaching methodologies, although no direct comparisons were made. The limited evidence available suggests that low-fidelity and low-cost models can be used for trainees without sacrificing educational quality.

Positive Valence Contributes to Hyperarticulation in Maternal Speech to Infants and Puppies.

Infant-directed speech often has hyperarticulated features, such as point vowels whose formants are further apart than in adult-directed speech. This increased "vowel space" may reflect the caretaker's effort to speak more clearly to infants, thus benefiting language processing. However, hyperarticulation may also result from more positive valence (e.g., speaking with positive vocal emotion) often found in mothers' speech to infants. This study was designed to replicate others who have found hyperarticulation in maternal speech to their 6-month-olds, but also to examine their speech to a non-human infant (i.e., a puppy). We rated both kinds of maternal speech for their emotional valence and recorded mothers' speech to a human adult. We found that mothers produced more positively valenced utterances and some hyperarticulation in both their infant- and puppy-directed speech, compared to their adult-directed speech. This finding promotes looking at maternal speech from a multi-faceted perspective that includes emotional state.

Family physicians' involvement in palliative cancer care.

BACKGROUND: Family physicians' (FPs) long-term relationships with their oncology patients position them ideally to provide primary palliative care, yet their involvement is variable. We examined perceptions of FP involvement among outpatients receiving palliative care at a cancer center and identified factors associated with this involvement. METHODS: Patients with advanced cancer attending an oncology palliative care clinic (OPCC) completed a 25-item survey. Eligible patients had seen an FP within 5 years. Binary multivariable logistic regression analyses were conducted to identify factors associated with (1) having seen an FP for palliative care within 6 months, and (2) having a scheduled/planned FP appointment. RESULTS: Of 258 patients, 35.2% (89/253) had seen an FP for palliative care within the preceding 6 months, and 51.2% (130/254) had a scheduled/planned FP appointment. Shorter travel time to FP (odds ratio [OR] = 0.67, 95% confidence interval [CI] = 0.48-0.93, p = 0.02), the FP having a 24-h support service (OR = 1.96, 95% CI = 1.02-3.76, p = 0.04), and a positive perception of FP's care (OR = 1.05, 95% CI = 1.01-1.09, p = 0.01) were associated with having seen the FP for palliative care. English as a first language (OR = 2.90, 95% CI = 1.04-8.11, p = 0.04) and greater ease contacting FP after hours (OR = 1.33, 95% CI = 1.08-1.64, p = 0.008) were positively associated, and female sex of patient (OR = 0.51, 95% CI = 0.30-0.87, p = 0.01) and travel time to FP (OR = 0.66, 95% CI = 0.47-0.93, p = 0.02) negatively associated with having a scheduled/planned FP appointment. Number of OPCC visits was not associated with either outcome. CONCLUSION: Most patients had not seen an FP for palliative care. Accessibility, availability, and equity are important factors to consider when planning interventions to encourage and facilitate access to FPs for palliative care.

TCR-Vγδ usage distinguishes protumor from antitumor intestinal γδ T cell subsets.

γδ T cells represent a substantial fraction of intestinal lymphocytes at homeostasis, but they also constitute a major lymphocyte population infiltrating colorectal cancers (CRCs); however, their temporal contribution to CRC development or progression remains unclear. Using human CRC samples and murine CRC models, we found that most γδ T cells in premalignant or nontumor colons exhibit cytotoxic markers, whereas tumor-infiltrating γδ T cells express a protumorigenic profile. These contrasting T cell profiles were associated with distinct T cell receptor (TCR)-Vγδ gene usage in both humans and mice. Longitudinal intersectional genetics and antibody-dependent strategies targeting murine γδ T cells enriched in the epithelium at steady state led to heightened tumor development, whereas targeting γδ subsets that accumulate during CRC resulted in reduced tumor growth. Our results uncover temporal pro- and antitumor roles for γδ T cell subsets.

Evaluating the Impact of Stakeholder Engagement in a School-Based Type 1 Diabetes Study.

OBJECTIVE: Although the importance of stakeholder engagement (SE) for patient-centered research is recognized, few studies document SE processes and influence on research outcomes in the diabetes field. We applied a research-informed framework to evaluate the impact of SE on a pediatric diabetes study exploring school nurse perspectives on modern diabetes devices. METHODS: We recruited parents of children with type 1 diabetes, school nurses, and diabetes providers. Stakeholders convened virtually every 2 months for 12 months. Goals for SE included input on research materials, interpretation of findings, and future research directions. Processes were assessed using a validated survey. Immediate outcomes included changes to research materials and satisfaction. Secondary outcomes included research efficiency and value (acceptance by community partners). RESULTS: Each role was represented at every meeting. The majority of stakeholders (>70%) completed the survey at study midpoint and end points. All surveyed indicated that they had received all desired information, shared feedback, and felt valued. Stakeholders were satisfied with the meeting frequency. Participants appreciated learning from each other and expressed enthusiasm for continued research participation. They described their role as one of consultant rather than research team members. SE resulted in five additional interview questions. Nearly 70 comments added to the interpretation of qualitative themes. Findings were published within 12 months and recognized by the state school nursing organization. CONCLUSION: SE was well received and led to meaningful changes in content and dissemination of a diabetes study. A systematic approach to evaluating SE can increase scientific rigor and reproducibility and contribute to best practices for SE in diabetes research.

FYN-TRAF3IP2 induces NF-κB signaling-driven peripheral T cell lymphoma.

Angioimmunoblastic T cell lymphoma (AITL) and peripheral T cell lymphoma not-otherwise-specified (PTCL, NOS) have poor prognosis and lack driver actionable targets for directed therapies in most cases. Here we identify FYN-TRAF3IP2 as a recurrent oncogenic gene fusion in AITL and PTCL, NOS tumors. Mechanistically, we show that FYN-TRAF3IP2 leads to aberrant NF-κB signaling downstream of T cell receptor activation. Consistent with a driver oncogenic role, FYN-TRAF3IP2 expression in hematopoietic progenitors induces NF-κB-driven T cell transformation in mice and cooperates with loss of the Tet2 tumor suppressor in PTCL development. Moreover, abrogation of NF-κB signaling in FYN-TRAF3IP2-induced tumors with IκB kinase inhibitors delivers strong anti-lymphoma effects in vitro and in vivo. These results demonstrate an oncogenic and pharmacologically targetable role for FYN-TRAF3IP2 in PTCLs and call for the clinical testing of anti-NF-κB targeted therapies in these diseases.

Development of a cumulative teaching score for tracking surgeon performance in undergraduate medical education

Background: Surgeon educators are important in undergraduate medical education (UME). However, teaching activities are undervalued and under-recognized compared with research, resulting in poorer quantity and quality of surgeon teaching. The purpose of this study was to investigate teaching roles available to surgeons and the amount of effort involved. Methods: A comprehensive review of all possible roles surgeons may take in UME at our institution was assembled. Delphi committee members were asked to evaluate each teaching role on the amount of effort needed per hour. Results were analyzed using descriptive statistics, and a Cronbach α of 0.60 or higher was the threshold to declare consensus. Results: Twenty-five participants, including physicians, residents and medical students, completed the study. Consensus was reached on the amount of effort needed for each teaching role. These values were used to prototype a cumulative teaching score that can be used to qualitatively quantify surgeon teaching. Conclusion: Surgeon teaching is important in UME, but not tracked and thus not valued. To improve the quantity and quality of surgeon teaching in UME, we need to track, reward and recognize surgeon teaching activities. The "effort score" we developed to objectively and transparently qualify teaching was able to determine the relative effort needed for each teaching activity in UME at the University of Toronto. Combining the effort score and time committed to each teaching activity will produce a cumulative teaching score for each instructor.

Contexte: Les chirurgiens formateurs jouent un rôle important pendant les études de premier cycle en médecine. Toutefois, les tâches d'enseignement sont sousévaluées et elles ne sont pas suffisamment reconnues comparativement aux activités de recherche, et cela nuit quantitativement et qualitativement à l'enseignement en chirurgie. Cette étude avait pour but d'analyser les divers rôles assumés par les chirurgiens formateurs et l'effort requis. Méthodes: Nous avons procédé à une revue complète de tous les rôles possibles assumés par les chirurgiens durant les études de premier cycle en médecine dans notre établissement. Les membres d'un comité Delphi ont été invités à évaluer chaque rôle de formateur au plan de l'effort requis par heure. Les résultats ont été analysés à l'aide de statistiques descriptives; et un coefficient α de Cronbach de 0,60 ou plus a servi de seuil consensuel. Résultats: Vingt-cinq participants, dont des médecins, des résidents et des étudiants en médecine, ont participé à l'étude. Un consensus a été atteint pour ce qui est de l'effort requis pour chaque rôle de formateur. Ces valeurs ont servi à élaborer le prototype d'un score cumulatif propre à l'enseignement qui peut être utilisé pour quantifier qualitativement l'enseignement par les chirurgiens. Conclusion: L'enseignement par les chirurgiens est important au premier cycle de la formation en médecine, mais ne fait l'objet ni d'un suivi ni d'une évaluation. Pour améliorer quantitativement et qualitativement l'enseignement en chirurgie au premier cycle, nous devons suivre, récompenser et reconnaître les diverses activités d'enseignement dans cette spécialité. L'« indice d'effort ¼ que nous avons élaboré pour qualifier de manière objective et transparente l'enseignement a permis de déterminer l'effort relatif requis pour chaque activité d'enseignement au premier cycle à l'Université de Toronto. En combinant l'indice d'effort et le temps consacré à chaque activité d'enseignement, on obtient un score cumulatif d'enseignement pour chaque instructeur.

Activating a Silver Lipoate Nanocluster with a Penicillin Backbone Induces a Synergistic Effect against S. aureus Biofilm.

Many antibiotic resistances to penicillin have been reported, making them obsolete against multiresistant bacteria. Because penicillins act by inhibiting cell wall production while silver particles disrupt the cell wall directly, a synergetic effect is anticipated when both modes of action are incorporated into a chimera cluster. To test this hypothesis, the lipoate ligands (LA) of a silver cluster (Ag29) of known composition (Ag29LA12)[3-] were covalently conjugated to 6-aminopenicillanic acid, a molecule with a ß-lactam backbone. Indeed, the partially conjugated cluster inhibited an Staphylococcus aureus biofilm, in a dose-response manner, with a half-maximal inhibitory concentration IC50 of 2.3 µM, an improvement over 60 times relative to the unconjugated cluster (IC50 = 140 µM). An enhancement of several orders of magnitude over 6-APA alone (unconjugated) was calculated (IC50 = 10 000 µM). Cell wall damage is documented via scanning electron microscopy. A synergistic effect of the conjugate was calculated by the combination index method described by Chou-Talalay. This hybrid nanoantibiotic opens a new front against multidrug-resistant pathogens.

Mothers say "baby" and their newborns do not choose to listen: a behavioral preference study to compare with ERP results.

Previously published results from neonatal brain evoked response potential (ERP) experiments revealed different brain responses to the single word "baby" depending on whether it was recorded by the mother or an unfamiliar female. These results are consistent with behavioral preference studies in which infants altered pacifier sucking to contingently activate recordings of the maternal vs. an unfamiliar female voice, but the speech samples were much longer and information-rich than in the ERP studies. Both types of neonatal voice recognition studies imply postnatal retention of prenatal learning. The preference studies require infant motor and motivation systems to mount a response in addition to voice recognition. The current contingent sucking preference study was designed to test neonatal motivation to alter behavior when the reward is the single word "baby" recorded by the mother or an unfamiliar speaker. Results showed an absent or weak contingent sucking response to the brief maternal voice sample, and they demonstrate the complementary value of electrophysiological and behavioral studies for very early development. Neonates can apparently recognize the maternal voice in brief recorded sample (previous ERP results) but they are not sufficiently motivated by it to alter sucking behavior.

Language experienced in utero affects vowel perception after birth: a two-country study.

AIMS: To test the hypothesis that exposure to ambient language in the womb alters phonetic perception shortly after birth. This two-country study aimed to see whether neonates demonstrated prenatal learning by how they responded to vowels in a category from their native language and another non-native language, regardless of how much postnatal experience the infants had. METHOD: A counterbalanced experiment was conducted in Sweden (n = 40) and the USA (n = 40) using Swedish and English vowel sounds. The neonates (mean postnatal age = 33 h) controlled audio presentation of either native or non-native vowels by sucking on a pacifier, with the number of times they sucked their pacifier being used to demonstrate what vowel sounds attracted their attention. The vowels were either the English/i/or Swedish/y/in the form of a prototype plus 16 variants of the prototype. RESULTS: The infants in the native and non-native groups responded differently. As predicted, the infants responded to the unfamiliar non-native language with higher mean sucks. They also sucked more to the non-native prototype. Time since birth (range: 7-75 h) did not affect the outcome. CONCLUSION: The ambient language to which foetuses are exposed in the womb starts to affect their perception of their native language at a phonetic level. This can be measured shortly after birth by differences in responding to familiar vs. unfamiliar vowels.

The role of early auditory development in attachment and communication.

Auditory perception and learning take place during the third trimester of gestation. Fetuses and newborns who lack typical auditory experience can go on to develop typical socioemotional attachment and language, given a supportive environment. For hospitalized preterm infants in developmentally sensitive neonatal intensive care units, detrimental effects of deviant early auditory experience may be remediated by later experience, but much is unknown about the causes of language deficits of prematurity. Prenatal auditory stimulation programs that incorporate audio speakers against the maternal belly should be discouraged because of possible overstimulation effects on the developing auditory system and sleep/wake state organization.

Prenatal Motherese? Newborn Speech Perception May Be Enhanced by Having a Young Sibling.

Prenatal experience with infant- and child-directed speech (IDS/CDS) may affect newborns' speech perception. We examined this possibility using an existing neonatal database from a recent cross-language study (Moon, Lagercrantz, & Kuhl, 2011). Seventy-three American and Swedish neonates (Mage = 32.58 hr, SD = 13.58 hr) were retrospectively coded as either having High (n = 32) or Low (n = 41) prenatal IDS/CDS exposure based on whether there were any children younger than 4 years old in the household during pregnancy. We compared the mean sucks for contingent presentations of prototypes and nonprototypes of vowel stimuli (native or foreign) among groups. A mixed 3-way ANOVA revealed a significant interaction: Neonates responded to prototypes and nonprototypes differently in the High IDS/CDS group, whereas there was a lack of differential responses in the Low IDS/CDS group. Future research with well-controlled measurement of prenatal speech is warranted.