Does serous tubal intraepithelial carcinoma (STIC) metastasize? The clonal relationship between STIC and subsequent high-grade serous carcinoma in BRCA1/2 mutation carriers several years after risk-reducing salpingo-oophorectomy

OBJECTIVE

The majority of high-grade serous carcinomas (HGSC) of the ovary, fallopian tube, and peritoneum arise from the precursor lesion called serous tubal intraepithelial carcinoma (STIC). It has been postulated that cells from STICs exfoliate into the peritoneal cavity and give rise to peritoneal HGSC several years later. While co-existent STICs and HGSCs have been reported to share similarities in their mutational profiles, clonal relationship between temporally distant STICs and HGSCs have been infrequently studied and the natural history of STICs remains poorly understood.

METHODS

We performed focused searches in two national databases from the Netherlands and identified a series of BRCA1/2 germline pathogenic variant (GPV) carriers (n = 7) who had STIC, and no detectable invasive carcinoma, at the time of their risk-reducing salpingo-oophorectomy (RRSO), and later developed peritoneal HGSC. The clonal relationship between these STICs and HGSCs was investigated by comparing their genetic mutational profile by performing next-generation targeted sequencing.

RESULTS

Identical pathogenic mutations and loss of heterozygosity of TP53 were identified in the STICs and HGSCs of five of the seven patients (71%), confirming the clonal relationship of the lesions. Median interval for developing HGSC after RRSO was 59 months (range: 24-118 months).

CONCLUSION

Our results indicate that cells from STIC can shed into the peritoneal cavity and give rise to HGSC after long lag periods in BRCA1/2 GPV carriers, and argues in favor of the hypothesis that STIC lesions may metastasize.

Equation of State and Thermometry of the 2D SU(N) Fermi-Hubbard Model

We characterize the equation of state (EoS) of the SU(N>2) Fermi-Hubbard Model (FHM) in a two-dimensional single-layer square optical lattice. We probe the density and the site occupation probabilities as functions of interaction strength and temperature for N=3, 4, and 6. Our measurements are used as a benchmark for state-of-the-art numerical methods including determinantal quantum Monte Carlo and numerical linked cluster expansion. By probing the density fluctuations, we compare temperatures determined in a model-independent way by fitting measurements to numerically calculated EoS results, making this a particularly interesting new step in the exploration and characterization of the SU(N) FHM.

Project Inclusive Genetics: Protecting reproductive autonomy from bias via prenatal patient-centered counseling

Clinician bias negatively impacts the healthcare received by marginalized communities. In this study, we explored factors that influence clinician and trainee bias against individuals with intellectual disabilities and its impact on clinical judgment in prenatal genetic testing settings. Specifically, we examined bias toward a fetus with a higher chance of developing a disability. We compared genetics specialists with their non-expert counterparts. This web-based study included clinical vignettes, implicit association tests (IATs), and an educational module. 595 participants were recruited via their institution or professional society. We conducted statistical analyses, including regression models controlling for key demographic characteristics, to analyze recommendation patterns and degree of change after the module. Genetics expertise strongly correlated with appropriate testing recommendation when the patient would not consider pregnancy termination (r = 1.784 pre-module, r = 1.502 post-module, p < 0.01). Factors that influenced pre-module recommendation to test include increased age (r = -0.029, p < 0.05), high religiosity (r = 0.525, p < 0.05), and participant personal preference against testing (r = 1.112, p < 0.01). Responses among participants without genetics expertise improved after the educational module (Z = -4.435, p < 0.01). 42% of non-experts who answered inappropriately changed their answer to match guidelines after the module. Individual bias, along with structural and institutional bias, permeates family planning encounters and significantly decreases quality of care. We demonstrate here that anti-bias training is effective, particularly for non-expert providers, and it can improve the care provided to individuals with intellectual disability. Evidence-based training such as this one can help providers make appropriate genetic counseling recommendations.

True coincidence summing correction for a BEGe detector in close geometry measurements

The true coincidence summing correction factor for a Broad Energy Germanium detector has been calculated at far and close geometry set-up using radioactive γ-ray sources. The correction factors were calculated using both experimental and analytical methods. Geant4 simulation was done to calculate the full-energy peak and total efficiencies of the detector. Standard, as well as fabricated mono-energetic γ-ray sources, were used for the γ-ray efficiency measurements. The simulated efficiencies of mono-energetic γ-ray sources were matched to the experimental γ-ray efficiencies by optimizing the detector parameters. The same parameters were used to obtain the full-energy peak and total efficiencies for γ-rays of current interest. Analytical and experimental correction factors were found to agree well with each other. The coincidence summing effect is found to be significant for source-to-detector distances less than 5 cm.

Genetics of Alzheimer's Disease in the African American Population

Black/African American (AA) individuals have a higher risk of Alzheimer's disease (AD) than White non-Hispanic persons of European ancestry (EUR) for reasons that may include economic disparities, cardiovascular health, quality of education, and biases in the methods used to diagnose AD. AD is also heritable, and some of the differences in risk may be due to genetics. Many AD-associated variants have been identified by candidate gene studies, genome-wide association studies (GWAS), and genome-sequencing studies. However, most of these studies have been performed using EUR cohorts. In this paper, we review the genetics of AD and AD-related traits in AA individuals. Importantly, studies of genetic risk factors in AA cohorts can elucidate the molecular mechanisms underlying AD risk in AA and other populations. In fact, such studies are essential to enable reliable precision medicine approaches in persons with considerable African ancestry. Furthermore, genetic studies of AA cohorts allow exploration of the ways the impact of genes can vary by ancestry, culture, and economic and environmental disparities. They have yielded important gains in our knowledge of AD genetics, and increasing AA individual representation within genetic studies should remain a priority for inclusive genetic study design.

Complete Heparin Reversal by Protamine during Off-Pump Coronary Artery Bypass Surgery (OPCAB): A Necessity or Myth?

In our country majority of the coronary artery bypass surgery (CABG) are done off-pump and was reported having excellent clinical outcome along with cost efficiency by various investigators. Heparin is commonly used as most effective anticoagulant, and protamine sulfate is now generally used to reverse the anticoagulant action of heparin. While under dosing of protamine may result in incomplete heparin reversal and prolonged anticoagulation, protamine overdosing is associated with impaired clot formation exerted by the intrinsic anti-coagulation properties of protamine itself, moreover protamine administration is associated with mild to severe cardiovascular and pulmonary complications. Apart from traditional full neutralization of heparin now-a-days, half dose protamine was also introduced showing good outcome regarding lower activated clotting time (ACT), overall, less surgical bleeding with less transfusion. This comparative study was designed to detect differences between traditional and decreased protamine dosing in Off-Pump Coronary Artery Bypass (OPCAB) surgery. Four hundred (400) patients who underwent Off-Pump Coronary Artery Bypass Surgery (OPCAB) surgery at our institution over a period of 12 months were analyzed and were divided into two groups. Group A- received 0.5mg of protamine per 100 unit of heparin; Group B-received 1.0mg of protamine per 100 unit of heparin. ACT, blood loss, hemoglobin and platelet count units of blood and blood product transfusion requirements, clinical outcome and hospital stay were assessed in each patient. This study showed that 0.5mg of protamine per 100 unit of heparin was always able to reverse the anticoagulant effect of heparin with no significant difference in hemodynamic parameters, amount of blood loss and requirements of blood transfusion in between the groups. A standard protamine dosing formula (protamine-heparin at ratio of 1:1) adequate for on-pump cardiac surgical procedures significantly overestimates protamine requirements for OPCAB. Patients treated with decreased protamine do not appear to have adverse outcomes in terms of post-operative bleeding.

O-199 Couples presenting to Infertility clinics - Are they really infertile?

Study question

Are couples presenting to infertility clinics actually infertile, or is there an undiagnosed underlying sexual dysfunction whose treatment can lead to natural conception avoiding the need for assisted reproductive techniques?

Summary answer

All couples presenting with infertility should be asked about sexual function. If sexual dysfunction is diagnosed, a signicant proportion can achieve pregnancy without assisted reproduction

What is known already

Infertility is defined as the inability to conceive after one year of frequent and regular unprotected sexual intercourse (SI). Although sexual histories are a key part of primary care screening guidelines for infertility, they are often overlooked during the infertility work-up. It is postulated that a large proportion of couples presenting to infertility clinics have underlying sexual dysfunction. Treatment through specialist counselling for couples with sexual dysfunction can help achieve pregnancy, negating the need for complex assisted reproductive techniques such as intravaginal insemination (IVI) and intrauterine insemination (IUl).

Study design, size, duration

108 couples were recruited from a national fertility clinic. The duration of the study was 3.5 years, from January 2016 to August 2019. The study was based primarily on surveys, where diagnostic work-up for infertility included tools for measuring sexual dysfunction, such as the IIEF-15 questionnaire. Our objectives were to find the extent of improvement of SI before and after specialist referral, and the time to conceive (TTC) in those with and without sexual dysfunction.

Participants/materials, setting, methods

Couples who never had successful completion of SI (despite producing an ejaculate sample) prior to clinic attendance were included. Treatment via specialist referral was then offered to these patients.

Data were analysed to compare outcomes between those who subsequently had successful SI (“Group A”) and those who had not had successful SI (“Group B”). Both groups were counselled for fertility treatments, such as IVI and IUI. TTC between the groups was analysed using Kaplan-Meier analysis

Main results and the role of chance

Out of 2057 couples presenting to the Infertility Clinic, 128 (5.98%) had never had successful SI. From this, 108 couples were included in the study. Two-thirds of couples revealed sexual difficulties at the beginning of the initial consultation. In men, erectile dysfunction was the predominant cause (70.4%, n = 76). In women, dyspareunia was the leading problem (18.2%, N = 20). Fertility investigations, which included hormone profiles, revealed normal results in most cases.

Treatment via referral to specialist sexual counselling was offered to all couples. Only 33 couples reported successful SI during subsequent visits (Group A). 13 of these 33 couples went on to conceive (11 naturally, 1 by IUI and 1 by IVI). The rest (n = 75), who had no improvement (Group B), had a significantly longer duration of sexual dysfunction, which was also more severe. Out of these 75 couples, 8 conceived (0 naturally, 6 by IVI, and 2 by IUI).The IIEF-15 scores (index for sexual dysfunction) between groups A and B were 10.72 ± 4.28 vs. 8 ± 4.73, P-value 0.0142. Group A couples (less severe sexual dysfunction) conceived earlier than Group B (mean duration 27.2 weeks vs. 48.8 weeks log-rank P value &lt;0.001).

Limitations, reasons for caution

The main limitations of this study include a small sample size and a small minority of couples refusing to undergo specialist counselling despite having sexual difficulties as they were only interested in assisted reproductive interventions such as IUl and IVI. These limitations hinder the internal/external validity of the study.

Wider implications of the findings

All couples presenting with infertility should be asked about sexual function. If sexual dysfunction is diagnosed, a signicant proportion can be helped to achieve pregnancy without assisted reproduction. In the cases of couples with persistent sexual difficulty, assisted reproductive techniques like IUI and IVI give a reasonable pregnancy rate.

Trial registration number

Not applicable

P-118 Timed Intercourse exacerbates the risk of sexual dysfunction in men &amp; women without an improvement in time to pregnancy

Study question

Investigate the differences in sexual dysfunction and time to pregnancy between infertile couples pursuing timed intercourse and Regular Intercourse (RI at least twice a week).

Summary answer

TI significantly increased the risk of SD compared to RI for both males and females after adjusting all other contributing factors.

What is known already

Timed Intercourse (TI) involves aligning sexual intercourse to the time around ovulation to increase the chance of conception in couples trying to conceive. Whilst TI is often advocated to increase conception rates and potentially accelerate the time to pregnancy (TTP) for infertile couples, the stressful nature of this approach may be associated with adverse effects such as sexual dysfunction (SD) within the couple.

Study design, size, duration

This prospective cohort study recruited 371 infertile couples who had been trying to conceive for more than a year, presenting to three regional infertility clinics between January 2016 and December 2018. 283 couples pursued TI and 88 couples pursued RI for a year, with all couples having no pre-existing sexual or psychiatric illness, and no medical contraindications to frequent intercourse.

Participants/materials, setting, methods

The SD score of both partners was assessed at the first visit using the validated Arizona Sexual Experiences Scale (ASEX) and the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-V). TTP was determined using Kaplan Meier Analysis in couples for whom natural conception was possible and no reversible fertility pathology was identified.

Main results and the role of chance

Timed Intercourse (TI) involves aligning sexual intercourse to the time around ovulation to increase the chance of conception in couples trying to conceive. Whilst TI is often advocated to increase conception rates and potentially accelerate the time to pregnancy (TTP) for infertile couples, the stressful nature of this approach may be associated with adverse effects such as sexual dysfunction (SD) within the couple.

TI significantly increased the risk of SD compared to RI for both males (Odds ratio [OR] 15.24, 95% confidence interval [CI] 7.96-29.15) and females (OR 5.52, 95% CI 2.38- 12.78), after adjusting for age, medical disorders, obesity, smoking, cause of infertility, and previous assisted reproductive techniques. TI carried a higher risk of developing erectile dysfunction, premature ejaculation, male hypoactive sexual dysfunction, female sexual interest-arousal disorder, and female orgasmic disorder. The TTP for natural conception was similar between TI and RI (p = 0.1365).

Limitations, reasons for caution

TI, a well-known strategy for increasing conception rates, did not improve time to natural conception compared to regular sexual intercourse. In contrast, the risk of sexual dysfunction in both men and women was significantly higher in TI, compared with RI.

Wider implications of the findings

This large study raises the question of effectiveness of the long-held belief that TI (intercourse limited around the ovulation-time, based on different methods of ovulation-prediction) improves pregnancy outcomes.

Trial registration number

N/A

Deconstructing Racism, Hierarchy, and Power in Medical Education: Guiding Principles on Inclusive Curriculum Design

In the context of current U.S. racial justice movements, analysis of racism in medicine within medical education is a critical task for all institutions. To educate the next generation of physicians about racism in medicine and out of concern that the curriculum required critical assessment and change, a group of students and faculty at Boston University School of Medicine (BUSM) initiated a longitudinal curricular analysis through a vertical integration group, commissioned by the Medical Education Committee, from May 2019 to June 2020. The curriculum analysis and the major outcomes and guiding principles that emerged from it are described as a path forward, toward a more inclusive curriculum. The major elements of this analysis included a comprehensive internal curricular assessment and an external assessment of peer institutions that led to the development of key curricular recommendations and overarching equity and specific racially focused equity competencies. The curricular recommendations fall into the following domains: (1) challenging the persistence of biological/genetic notions of race, (2) embedding structural practices in medical education to dismantle racism in medicine, and (3) promoting institutional climate change. Initial steps to implement these recommendations are described. The authors believe that the historic and present reality of racism in America and in medicine has impacted medical education specifically, and more broadly, the practice of medicine, trainee experience, and patient outcomes. The key findings of the BUSM analysis are transferable to other medical education institutions, and the described review process can support peer institutions as they engage in the imperative work of institutional reflection and addressing the salient ideas and practices that uphold racism in medicine.

Role of power distance phenomena in blended learning in higher education post-Covid-19

COVID has posed several challenges for higher education. There is a rise in blended teaching and learning models that can improve the quality of education, observed Raman. Classroom interaction vital in quality of education is affected by power distance between the teacher and students, states Kasuya. Much research has been done on blended learning but hardly any on the role of power distance in blended learning in higher education, specifically post COVID. Keeping in mind the growing significance of blended learning shortly, it becomes strategically important to understand the role of power distance in blended learning in higher education post-COVID-19. This research paper tries to address the research gap. The study is exploratory, exploring the role of power distancing in blended learning formats during post-COVID-19. The findings indicate that there is a relationship between power distance and the autonomy of an individual. The higher the power distance between a teacher and a student from the teacher’s perspective, it becomes teacher-centred learning. So blended learning with the best of low power distances in terms of the media and delivery mechanism of offline and online ensures the mitigation of power between the teacher and the taught. The research will help the universities create a perfect blended learning format that enhances the quality of higher education. Due to the paucity of time and resources and a ban on respondent interaction due to pandemics, this research is based on secondary data analysis.

Realizing topological edge states with Rydberg-atom synthetic dimensions

A discrete degree of freedom can be engineered to match the Hamiltonian of particles moving in a real-space lattice potential. Such synthetic dimensions are powerful tools for quantum simulation because of the control they offer and the ability to create configurations difficult to access in real space. Here, in an ultracold ⁸⁴Sr atom, we demonstrate a synthetic-dimension based on Rydberg levels coupled with millimeter waves. Tunneling amplitudes between synthetic lattice sites and on-site potentials are set by the millimeter-wave amplitudes and detunings respectively. Alternating weak and strong tunneling in a one-dimensional configuration realizes the single-particle Su-Schrieffer-Heeger (SSH) Hamiltonian, a paradigmatic model of topological matter. Band structure is probed through optical excitation from the ground state to Rydberg levels, revealing symmetry-protected topological edge states at zero energy. Edge-state energies are robust to perturbations of tunneling-rates that preserve chiral symmetry, but can be shifted by the introduction of on-site potentials.

Synthetic dimensions, states of a system engineered to act as if they were a reconfigurable extra spatial dimension, have been demonstrated with different systems previously. Here the authors create a synthetic dimension using Rydberg atoms and configure it to support topological edge states.

BOX engineering to mitigate negative differential resistance in MFIS negative capacitance FDSOI FET: an analog perspective

Till date, the existing understanding of negative differential resistance (NDR) is obtained from metal-ferro-metal-insulator-semiconductor (MFMIS) FET, and it has been utilized for both MFMIS and metal-ferro-insulator-semiconductor (MFIS) based NCFETs. However, in MFIS architecture, the ferroelectric capacitance (C_FE) is not a lumped capacitance. Therefore, for MFIS negative capacitance (NC) devices, the physical explanation which governs the NDR mechanism needs to be addressed. In this work, for the first time, we present the first principle explanation of the NDR effect in MFIS NC FDSOI. We found that the output current variation with the drain to source voltage (V_DS), (i.e.g_ds) primarily depends upon two parameters: (a)V_DSdependent inversion charge gradient (∂n/∂V_DS); (b)V_DSsensitive electron velocity (∂v/∂V_DS), and the combined effect of these two dependencies results in NDR. Further, to mitigate the NDR effect, we proposed the BOX engineered NC FDSOI FET, in which the buried oxide (BOX) layer is subdivided into the ferroelectric (FE) layer and the SiO₂layer. In doing so, the inversion charge in the channel is enhanced by the BOX engineered FE layer, which in turn mitigates the NDR and a nearly zerog_dswith a minimal positive slope has been obtained. Through well-calibrated TCAD simulations, by utilizing the obtained positiveg_ds, we also designed aV_DSindependent constant current mirror which is an essential part of analog circuits. Furthermore, we discussed the impact of the FE parameter (remanent polarization and coercive field) variation on the device performances. We have also compared the acquired results with existing literature on NC-based devices, which justifies that our proposed structure exhibits complete diminution of NDR, thus enabling its use in analog circuit design.

Triangle Singularity as the Origin of the a_{1}(1420)

The COMPASS Collaboration experiment recently discovered a new isovector resonancelike signal with axial-vector quantum numbers, the a_{1}(1420), decaying to f_{0}(980)π. With a mass too close to and a width smaller than the axial-vector ground state a_{1}(1260), it was immediately interpreted as a new light exotic meson, similar to the X, Y, Z states in the hidden-charm sector. We show that a resonancelike signal fully matching the experimental data is produced by the decay of the a_{1}(1260) resonance into K^{*}(→Kπ)K[over ¯] and subsequent rescattering through a triangle singularity into the coupled f_{0}(980)π channel. The amplitude for this process is calculated using a new approach based on dispersion relations. The triangle-singularity model is fitted to the partial-wave data of the COMPASS experiment. Despite having fewer parameters, this fit shows a slightly better quality than the one using a resonance hypothesis and thus eliminates the need for an additional resonance in order to describe the data. We thereby demonstrate for the first time in the light-meson sector that a resonancelike structure in the experimental data can be described by rescattering through a triangle singularity, providing evidence for a genuine three-body effect.

B-cell clusters at the invasive margin associate with longer survival in early-stage oral-tongue cancer patients

In oral-cancer, the number of tumor-infiltrating lymphocytes (TILs) associates with improved survival, yet the prognostic value of the cellular composition and localization of TILs is not defined. We quantified densities, localizations, and cellular networks of lymphocyte populations in 138 patients with T1-T2 primary oral-tongue squamous cell carcinoma treated with surgical resections without any perioperative (chemo)radiotherapy, and correlated outcomes to overall survival (OS). Multiplexed in-situ immunofluorescence was performed for DAPI, CD4, CD8, CD20, and pan-cytokeratin using formalin-fixed paraffin-embedded sections, and spatial distributions of lymphocyte populations were assessed in the tumor and stroma compartments at the invasive margin (IM) as well as the center of tumors. We observed a high density of CD4, CD8, and CD20 cells in the stroma compartment at the IM, but neither lymphocyte densities nor networks as single parameters associated with OS. In contrast, assessment of two contextual parameters within the stroma IM region of tumors, i.e., the number of CD20 cells within 20 µm radii of CD20 and CD4 cells, termed the CD20 Cluster Score, yielded a highly significant association with OS (HR 0.38; p = .003). Notably, the CD20 Cluster Score significantly correlated with better OS and disease-free survival in multivariate analysis (HR 0.34 and 0.47; p = .001 and 0.019) as well as with lower local recurrence rate (OR: 0.13; p = .028). Taken together, our study showed that the presence of stromal B-cell clusters at IM, in the co-presence of CD4 T-cells, associates with good prognosis in early oral-tongue cancer patients.

A Literature Systematic Review with Meta-Analysis of Symptoms Prevalence in Covid-19: the Relevance of Olfactory Symptoms in Infection Not Requiring Hospitalization

PURPOSE OF REVIEW

To investigate the association between the olfactory dysfunction and the more typical symptoms (fever, cough, dyspnoea) within the Sars-CoV-2 infection (COVID-19) in hospitalized and non-hospitalized patients.

RECENT FINDINGS

PubMed, Scopus and Web of Science databases were reviewed from May 5, 2020, to June 1, 2020. Inclusion criteria included English, French, German, Spanish or Italian language studies containing original data related to COVID19, anosmia, fever, cough, and dyspnoea, in both hospital and non-hospital settings. Two investigators independently reviewed all manuscripts and performed quality assessment and quantitative meta-analysis using validated tools. A third author arbitrated full-text disagreements. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), 11 of 135 studies fulfilled eligibility. Anosmia was estimated less prevalent than fever and cough (respectively rate difference = - 0.316, 95% CI: - 0.574 to - 0.058, Z = - 2.404, p < 0.016, k = 11 and rate difference = - 0.249, 95% CI: - 0.402 to - 0.096, Z = - 3.185, p < 0.001, k = 11); the analysis between anosmia and dyspnoea was not significant (rate difference = - 0.008, 95% CI: - 0.166 to 0.150, Z = - 0.099, p < 0.921, k = 8). The typical symptoms were significantly more frequent than anosmia in hospitalized more critical patients than in non-hospitalized ones (respectively [Q(1) = 50.638 p < 0.000, Q(1) = 52.520 p < 0.000, Q(1) = 100.734 p < 0.000).

SUMMARY

Patient with new onset olfactory dysfunction should be investigated for COVID-19. Anosmia is more frequent in non-hospitalized COVID-19 patients than in hospitalized ones.

Unraveling the Origin of Differentiable 'Turn-On' Fluorescence Sensing of Zn2+ and Cd2+ Ions with Squaramides

A squaramide ring conjugated with Schiff-bases decorated with hydroxy and methoxy functional groups differentially senses zinc and cadmium ions, which turn on the fluorescence. The feebly emitting free ligands light up in the presence of zinc and cadmium acetates, with the acetate ion playing a pivotal role as a conjugate anion. The selective and differentiable emission responses for zinc and cadmium ions make these ligands efficient multi-analyte sensing agents. Furthermore, these ligands could be used to differentially sense zinc and cadmium ions even in aqueous environments. The NMR investigations reveal marginal differences in the binding of zinc and cadmium ions to the ligands, whereas density functional theory calculations suggest the different extent of ligand-to-metal charge transfer (LMCT) contributes to the differential behavior. Finally, comparison of the excited-state dynamics of free ligand and the metal complexes reveal the appearance of longer lifetime (about 500-700 ps) component with complexation, due to rigidified molecular skeleton, thereby impeding the non-radiative processes.

Complexities of Clinical Genetics Consultation: An Interprofessional Clinical Skills Workshop

INTRODUCTION

Advances in genomic medicine contribute to increased demand for clinical genetics services and require physicians to understand the interprofessional practice of this field. Medical students receive a foundation in genetics during preclinical studies, but variability in clinical experience may limit knowledge of and recruitment into this clinical specialty. In this resource, we describe an approach for simulating exposure to the practice of clinical genetics during the core pediatrics clerkship.

METHODS

Prior to class, students researched and considered a mock genetics case. In class, each of four small groups discussed two cases demonstrating varied presentations, with facilitation by genetic counseling students. Each case highlighted the variability in presentation, testing, management strategies, and psychosocial issues of a genetics case. Groups reported out to the class, and individuals completed an anonymous evaluation survey.

RESULTS

Surveys were distributed to nine of 10 pilot sessions (210 of 235 students) with a response rate of 48%. Students frequently reported no previous exposure to seeing patients with genetics professionals, indicated a preference for learning in case discussion format over traditional lectures, and felt the format helped them apply clinical skills and reasoning. Medical students appreciated the opportunity to interact with genetic counseling students in an interdisciplinary setting and desired further educational opportunities regarding delivering complex information to patients and their families.

DISCUSSION

This session expanded exposure to clinical genetics content and professionals, serving as an important foundation for further development of genetic knowledge during clinical training.

Granular dot-like staining with MLH1 immunohistochemistry is a clone-dependent artefact

Immunohistochemistry (IHC) for DNA mismatch repair proteins MLH1, PMS2, MSH2, and MSH6 is used for microsatellite instability (MSI) screening in colorectal carcinoma (CRC) and endometrial carcinoma (EC). Loss of PMS2, with retained MLH1 staining occurs in germline mutations of PMS2 gene, and is an indication for genetic testing. We report a pitfall of immunohistochemical interpretation in an EC, initially regarded as MLH1-positive and PMS2-negative. Review of the MLH1-IHC (M1-clone) revealed a granular, dot-like, nuclear staining. On repeating the MLH1-IHC with a different clone (ES05-clone), complete negativity was noted, and on molecular testing, MLH1 promotor methylation was detected. The dot-like pattern was therefore adjudged a clone-dependent artefact. On reviewing the archived MLH1-IHC slides, we observed the same dot-like pattern in two CRCs; in both cases the M1-clone had been used. Awareness of this artefact may prevent reporting errors, and unnecessary referrals for germline mutation testing.