Efficiency of moderately hypofractionated radiotherapy in NSCLC cell model.

Background: The current standard of radiotherapy for inoperable locally advanced NSCLCs with single fraction doses of 2.0 Gy, results in poor outcomes. Several fractionation schedules have been explored that developed over the past decades to increasingly more hypofractionated treatments. Moderate hypofractionated radiotherapy, as an alternative treatment, has gained clinical importance due to shorter duration and higher patient convenience. However, clinical trials show controversial results, adding to the need for pre-clinical radiobiological studies of this schedule. Methods: We examined in comparative analysis the efficiency of moderate hypofractionation and normofractionation in four different NSCLC cell lines and fibroblasts using several molecular-biological approaches. Cells were daily irradiated with 24x2.75 Gy (moderate hypofractionation) or with 30x2 Gy (normofractionation), imitating the clinical situation. Proliferation and growth rate via direct counting of cell numbers, MTT assay and measurements of DNA-synthesizing cells (EdU assay), DNA repair efficiency via immunocytochemical staining of residual γH2AX/53BP1 foci and cell surviving via clonogenic assay (CSA) were experimentally evaluated. Results: Overall, the four tumor cell lines and fibroblasts showed different sensitivity to both radiation regimes, indicating cell specificity of the effect. The absolute cell numbers and the CSA revealed significant differences between schedules (P < 0.0001 for all employed cell lines and both assays) with a stronger effect of moderate hypofractionation. Conclusion: Our results provide evidence for the similar effectiveness and toxicity of both regimes, with some favorable evidence towards a moderate hypofractionation. This indicates that increasing the dose per fraction may improve patient survival and therapy outcomes.

Genome-wide association analyses of ovarian cancer patients undergoing primary debulking surgery identify candidate genes for residual disease.

Survival from ovarian cancer depends on the resection status after primary surgery. We performed genome-wide association analyses for resection status of 7705 ovarian cancer patients, including 4954 with high-grade serous carcinoma (HGSOC), to identify variants associated with residual disease. The most significant association with resection status was observed for rs72845444, upstream of MGMT, in HGSOC (p = 3.9 × 10-8). In gene-based analyses, PPP2R5C was the most strongly associated gene in HGSOC after stage adjustment. In an independent set of 378 ovarian tumours from the AGO-OVAR 11 study, variants near MGMT and PPP2R5C correlated with methylation and transcript levels, and PPP2R5C mRNA levels predicted progression-free survival in patients with residual disease. MGMT encodes a DNA repair enzyme, and PPP2R5C encodes the B56γ subunit of the PP2A tumour suppressor. Our results link heritable variation at these two loci with resection status in HGSOC.

Safety, feasibility, and impact on the gut microbiome of kefir administration in critically ill adults.

BACKGROUND: Dysbiosis of the gut microbiome is frequent in the intensive care unit (ICU), potentially leading to a heightened risk of nosocomial infections. Enhancing the gut microbiome has been proposed as a strategic approach to mitigate potential adverse outcomes. While prior research on select probiotic supplements has not successfully shown to improve gut microbial diversity, fermented foods offer a promising alternative. In this open-label phase I safety and feasibility study, we examined the safety and feasibility of kefir as an initial step towards utilizing fermented foods to mitigate gut dysbiosis in critically ill patients. METHODS: We administered kefir in escalating doses (60 mL, followed by 120 mL after 12 h, then 240 mL daily) to 54 critically ill patients with an intact gastrointestinal tract. To evaluate kefir's safety, we monitored for gastrointestinal symptoms. Feasibility was determined by whether patients received a minimum of 75% of their assigned kefir doses. To assess changes in the gut microbiome composition following kefir administration, we collected two stool samples from 13 patients: one within 72 h of admission to the ICU and another at least 72 h after the first stool sample. RESULTS: After administering kefir, none of the 54 critically ill patients exhibited signs of kefir-related bacteremia. No side effects like bloating, vomiting, or aspiration were noted, except for diarrhea in two patients concurrently on laxatives. Out of the 393 kefir doses prescribed for all participants, 359 (91%) were successfully administered. We were able to collect an initial stool sample from 29 (54%) patients and a follow-up sample from 13 (24%) patients. Analysis of the 26 paired samples revealed no increase in gut microbial α-diversity between the two timepoints. However, there was a significant improvement in the Gut Microbiome Wellness Index (GMWI) by the second timepoint (P = 0.034, one-sided Wilcoxon signed-rank test); this finding supports our hypothesis that kefir administration can improve gut health in critically ill patients. Additionally, the known microbial species in kefir were found to exhibit varying levels of engraftment in patients' guts. CONCLUSIONS: Providing kefir to critically ill individuals is safe and feasible. Our findings warrant a larger evaluation of kefir's safety, tolerability, and impact on gut microbiome dysbiosis in patients admitted to the ICU. TRIAL REGISTRATION: NCT05416814; trial registered on June 13, 2022.

Association of two genomic variants with HPV type-specific risk of cervical cancer.

PROBLEM: Human papillomavirus infection is integral to developing invasive cervical cancer in the majority of patients. In a recent genome-wide association study, rs9357152 and rs4243652 have been associated with seropositivity for HPV16 or HPV18, respectively. It is unknown whether these variants also associate with cervical cancer triggered by either HPV16 or HPV18. METHODS: We investigate whether the two HPV susceptibility variants show association with type-specific cervical cancer in a genetic case-control study with cases stratified by HPV16 or HPV18, respectively. We further tested whether rs9357152 modulates gene expression of any of 36 genes at the human leukocyte antigen locus in 256 cervical tissues. RESULTS: rs9357152 was associated with invasive HPV16-positive cervical cancer (OR 1.33, 95%CI 1.03-1.70, p = 0.03), and rs4243652 was associated with HPV18-positive adenocarcinomas (OR 2.96, 95%CI 1.18-7.41, p = 0.02). These associations remained borderline significant after testing against different sets of controls. rs9357152 was found to be an eQTL for HLA-DRB1 in HPV-positive cervical tissues (pANOVA = 0.0009), with the risk allele lowering mRNA levels. CONCLUSIONS: We find evidence that HPV seropositivity variants at chromosome 6 and 14 may modulate type-specific cervical cancer risk. rs9357152 may exert its effect through regulating HLA-DRB1 induction in the presence of HPV. In regard of multiple testing, these results need to be confirmed in larger studies.

Multi-trait genome-wide association study identifies a novel endometrial cancer risk locus that associates with testosterone levels.

To detect novel endometrial cancer risk variants, we leveraged information from endometrial cancer risk factors in a multi-trait GWAS analysis. We first assessed causal relationships between established and suspected endometrial cancer risk factors, and endometrial cancer using Mendelian randomization. Following multivariable analysis, five independent risk factors (waist circumference, testosterone levels, sex hormone binding globulin levels, age at menarche, and age at natural menopause) were included in a multi-trait Bayesian GWAS analysis. We identified three potentially novel loci that associate with endometrial cancer risk, one of which (7q22.1) replicated in an independent endometrial cancer GWAS dataset and was genome-wide significant in a meta-analysis. This locus may affect endometrial cancer risk through altered testosterone levels. Consistent with this, we observed colocalization between the signals for endometrial cancer risk and expression of CYP3A7, a gene involved in testosterone metabolism. Thus, our findings suggest opportunities for hormone therapy to prevent or treat endometrial cancer.

Estradiol and Dihydrotestosterone Levels in COVID-19 Patients.

OBJECTIVE: To determine differences in plasma sex hormone levels in male and female coronavirus disease 2019 (COVID-19) patients and healthy volunteers (HVs) because cell entry of severe acute respiratory syndrome coronavirus 2 occurs via the angiotensin-converting enzyme 2 receptor which is downregulated by 17ß-estradiol. PATIENTS AND METHODS: Citrated plasma samples were collected from 101 patients with COVID-19 upon presentation to the emergency department and from 40 HVs between November 1, 2020, and May 30, 2021. Plasma 17ß-estradiol and 5α-dihydrotestosterone (DHT) levels were measured using enzyme-linked immunosorbent assay (pg/mL). Data are presented as median and quartiles (IQR). Wilcoxon rank sum test with a P value less than .05 was considered significant. RESULTS: Patients with COVID-19 (median age, 49 years) included 51 males and 50 females (25 postmenopausal). Hospital admission was required for 58.8% of male patients (n = 30) and 48.0% of female patients (n = 24) (66.7% postmenopausal, n = 16) Healthy volunteers (median age, 41 years) included 20 males and 20 females (9 postmenopausal). Female patients with COVID-19 were found to have decreased 17ß-estradiol levels (18.5 [IQR, 10.5-32.3] pg/mL; 41.4 [IQR, 15.5-111.0] pg/mL, P=.025), and lower 17ß-estradiol to DHT ratios (0.073 [IQR, 0.052-0.159] pg/mL; 0.207 [IQR, 0.104-0.538] pg/mL, P=.015) than female HVs. Male patients with COVID-19 were found to have decreased DHT levels (302.8 [IQR, 249.9-470.8] pg/mL; 457.2 [IQR, 368.7-844.3] pg/mL, P=.005), compared with male HVs. Levels of DHT did not differ between female patients with COVID-19 and female HVs, whereas 17ß-estradiol levels did not differ between male patients with COVID-19 and male HVs. CONCLUSION: Sex hormone levels differ between patients with COVID-19 and HVs, with sex-specific patterns of hypogonadism in males and females. These alterations may be associated with disease development and severity.

Plasma thrombin generation kinetics vary by injury pattern and resuscitation characteristics in pediatric and young adult trauma patients.

BACKGROUND: Thrombin generation kinetics are not well studied in children. This study aimed to assess how thrombin generation kinetics vary in pediatric and young adult (YA) trauma patients by clinical characteristics and injury pattern. METHODS: Prospective cohort study where plasma samples were obtained from pediatric (ages 0-17 years) and YA (ages 18-21 years) trauma patients upon emergency department arrival. Thrombin generation (calibrated automated thrombogram [CAT]) was quantified as lag time (LT, minutes), peak height (PH, nM), time to peak (ttPeak, minutes), and endogenous thrombin potential (ETP, nM × minute). Results are expressed as median and quartiles [Q1, Q3] and compared using Wilcoxon rank sum testing with p < 0.05 considered significant. RESULTS: We enrolled 47 pediatric (median age, 15 [14, 17] years, 78% male, 87% blunt, median Injury Severity Score, 12) and 49 YA (median age 20 [18, 21] years, 67% male, 84% blunt, median Injury Severity Score, 12) patients. Pediatric and YA patients had similar rates of operative intervention (51% vs. 57%), transfusion (25% vs. 20%), and traumatic brain injury (TBI) (53% vs. 49%). Pediatric patients who required an operation had accelerated initiation of thrombin generation, with shorter LT than those who did not (2.58 [2.33, 2.67]; 2.92 [2.54, 3.00], p = 0.034). Shorter LT (2.41 [2.22, 2.67]; 2.67 [2.53, 3.00]) and ttPeak (4.50 [4.23, 4.73]; 5.22 [4.69, 5.75], both p < 0.01) were noted in pediatric patients who required transfusion as compared with those who did not. The YA patients requiring transfusion had shorter LT (2.33 [2.19, 2.74]; 2.83 [2.67, 3.27]) and ttPeak (4.48 [4.33, 5.65]; 5.33 [4.85, 6.28] both p < 0.04) than those who were not transfused. Young adults with TBI had greater ETP than those without (1509 [1356, 1671]; 1284 [1154, 1471], p = 0.032). CONCLUSION: Thrombin generation kinetics in pediatric trauma patients prior to intervention vary with need for operation and transfusion, while thrombin generation kinetics in young adult patients are influenced by TBI and need for operation or transfusion. This is a promising tool for assessing coagulopathy in young trauma patients. LEVEL OF EVIDENCE: Prognostic and Epidemiological; Level III.

Right Ventricular Systolic Dysfunction in Adults With Anatomic Repair of d-Transposition of Great Arteries.

The purpose of this study was to assess the prevalence of right ventricular (RV) systolic dysfunction in adults with anatomic repair of dextro-transposition of great arteries (d-TGAs), and to determine its relation to clinical outcomes across multiple domains (functional status, peak oxygen consumption, N-terminal pro-brain natriuretic peptide, and heart failure hospitalization). Adults with anatomic repair for d-TGA and with echocardiographic images for strain analysis were divided into 2 groups: (1) d-TGA status after an arterial switch operation (d-TGA-ASO group) and (2) d-TGA status after a Rastelli operation (d-TGA-Rastelli group). RV systolic function was assessed using RV global longitudinal strain (RVGLS), and RV systolic dysfunction was defined as RVGLS >-18%. We identified 151 patients (median age 21 years [19 to 28]; d-TGA-ASO group 89 [59%], and d-TGA-Rastelli group 62 [41%]). The mean RVGLS was -22 ± 4%, and 47 patients (31%) had RV systolic dysfunction. The d-TGA-Rastelli group had lower (less negative) RVGLS than that of the d-TGA-ASO group (-19 ± 3% vs -25 ± 3%, p <0.001) and higher prevalence of RV systolic dysfunction (48% vs 19%, p <0.001). RVGLS (absolute value) was associated with peak oxygen consumption (r = 0.58, p <0.001; adjusted R2 = 0.28), log-N-terminal pro-brain natriuretic peptide (r = -0.41, p = 0.004; adjusted R2 = 0.21), New York Heart Association class III/IV (odds ratio 2.29, 1.56 to 3.19, p = 0.01), and heart failure hospitalization (hazard ratio 0.93, 0.88 to 0.98, p = 0.009). RV systolic dysfunction was common in adults with d-TGA and anatomic repair and was associated with clinical outcomes. Longitudinal studies are required to determine the risk factors for progressive RV systolic dysfunction and to identify strategies for preventing RV systolic dysfunction in this population.

TELOMERE LENGTH OF PERIPHERAL BLOOD MONONUCLEAR CELLS IS ASSOCIATED WITH DISCHARGE DISPOSITION IN OLDER TRAUMA PATIENTS.

Introduction: Little is known regarding peripheral blood mononuclear cell telomere length (PBMC-TL) and response to traumatic injury. The objective of this study was to characterize the role of PBMC-TL in coagulation and clinical outcomes after injury. Methods: Plasma and buffy coats were prospectively collected from trauma patients and healthy volunteers. DNA was purified and PBMC-TL quantified by quantitative polymerase chain reaction. Thrombin generation kinetics were expressed as lag time (in minutes), peak height (in nanometers), time to peak (in minutes), and endogenous thrombin potential (in nM × min). Results are in median and quartiles [Q1, Q3]. P < 0.05 was considered significant (Wilcoxon rank sum testing). Results: Forty-two younger patients (21 [20, 22] years, 69% were male) and 39 older patients (62 [61, 64] years, 79% were male) were included. There was no significant difference in Clinical Frailty Scores between groups. Younger patients had longer total PBMC-TL (0.40 Mb [0.30, 0.49] vs. 0.29 Mb [0.23, 0.33], P < 0.001) and longer average PBMC-TL per chromosome (4.3 kb [3.3, 5.3] vs. 3.2 kb [2.5, 3.7], P < 0.001). When older patients were stratified by 50th percentile of PBMC-TL, there were no differences in thrombin generation; however, those with shorter telomeres were less likely to be discharged home (29% vs. 77%, P = 0.004). Older patients in the bottom quartile of PBMC-TL had shorter lag time (2.78 min [2.33, 3.00] vs. 3.33 min [3.24, 3.89], P = 0.030) and were less likely to be discharged home (22% vs. 90%, P = 0.006) than those in the top quartile of PBMC-TL. Multivariable logistic regression models revealed both increased age and shorter PBMC-TL to be independent predictors of discharge disposition other than home. Conclusion: In older trauma patients, shorter PBMC-TL is associated with accelerated initiation of thrombin generation and lower likelihood of being discharged to home.

Risk of pulmonary artery dissection in adults with congenital heart disease.

BACKGROUND: There are limited data about the risk of pulmonary artery (PA) dissection in adults with congenital heart disease (CHD), and the purpose of this study was to estimate the incidence of PA dissection in this population. METHODS: Retrospective cohort study of adults with CHD that underwent cross-sectional imaging (2003-2020). PA aneurysm was defined as main or branch PA diameter > 40 mm or > 30 mm respectively, and severe PA aneurysm was defined as main or branch PA diameter > 50 mm. RESULTS: Of 1, 673 patients (41 ± 10 years; male 58%), 493 (24%), 286 (19%), and 306 (20%) had aneurysms of the main, right, and left PA respectively, while 66 (4%) had severe PA aneurysm. During a median follow-up of 8.2 (interquartile range 3.7-10.3) years, there was one PA dissection in a patient with Eisenmenger syndrome, thus the incidence of PA dissection was 14 per 100,000 patient-years. Of 779 females, 163 had one or more pregnancies during follow-up, and 41 (25%) of these patients had known PA aneurysm at the time of conception. There was no PA dissection during pregnancy. Of the 163 patients, 91 (56%) had cross-sectional imaging before and after pregnancy, there was no significant difference in PA dimension before versus after pregnancy (main PA 35 ± 5 versus 36 ± 4 mm, p = 0.6; right PA 21 ± 3 versus 33 ± 4 mm, p = 0.1; and left PA 23 ± 4 versus 22 ± 4 mm, p = 0.4). CONCLUSIONS: The risk of PA dissection was extremely low even in patients with severe PA aneurysm, or in patients with PA aneurysm that became pregnant. Collectively, these data suggest a benign natural history for patients without severe pulmonary hypertension and encourage and a conservative approach in managing patients with PA aneurysm.

Estimation of Left Ventricular Filling Pressure Using Left Atrial Strain in Coarctation of Aorta.

BACKGROUND: Left atrial (LA) reservoir strain <18% and booster strain <8% have been proposed as the optimal threshold to detect increased left ventricular (LV) filling pressure in patients with acquired heart disease. The purpose of this study was to determine whether these LA strain cut-off points can detect increased LV filling pressure in adults with coarctation of aorta (COA). METHODS: This retrospective study included adults with COA (n = 126; age, 36 ± 16 years) who underwent non-simultaneous cardiac catheterization and echocardiography. Increased LV filling pressure was defined as pulmonary artery wedge pressure (PAWP) >12 mm Hg or LV end-diastolic pressure (LVEDP) >16 mm Hg. RESULTS: The median PAWP was 13 mm Hg (interquartile range [IQR], 11-18) and PAWP had a good correlation with LA reservoir strain (r = -0.69; P<.001) and LA booster strain (r = -0.61; P<.001). LA reservoir strain <18% had superior diagnostic power to detect PAWP >12 mm Hg as compared with LA volume index >34 mL/m², septal E/e' >15, lateral E/e' >13, and tricuspid regurgitation velocity >2.8 m/s (P<.05 for all). The median LVEDP was 17 mm Hg (IQR, 14-20) and LVEDP had a modest correlation with LA reservoir strain (r = -0.39; P<.001) and LA booster strain (r = -0.33; P<.01). LA reservoir strain <18% had superior diagnostic power to detect LVEDP >16 mm Hg as compared with LA volume index >34 mL/m², septal E/e' >15, lateral E/e' >13, and tricuspid regurgitation velocity >2.8 m/s (P<.05 for all). CONCLUSIONS: These data suggest that LA strain could potentially be used to identify patients with increased LV filling pressure, thereby improving patient selection for cardiac catheterization and interventions.

Effectiveness of hypofractionated and normofractionated radiotherapy in a triple-negative breast cancer model.

Breast cancer (BC) is one of the most diagnosed malignant carcinomas in women with a triple-negative breast cancer (TNBC) phenotype being correlated with poorer prognosis. Fractionated radiotherapy (RT) is a central component of breast cancer management, especially after breast conserving surgery and is increasingly important for TNBC subtype prognosis. In recent years, moderately hypofractionated radiation schedules are established as a standard of care, but many professionals remain skeptical and are concerned about their efficiency and side effects. In the present study, two different triple-negative breast cancer cell lines, a non-malignant breast epithelial cell line and fibroblasts, were irradiated daily under normofractionated and hypofractionated schedules to evaluate the impact of different irradiation regimens on radiation-induced cell-biological effects. During the series of radiotherapy, proliferation, growth rate, double-strand DNA break-repair (DDR), cellular senescence, and cell survival were measured. Investigated normal and cancer cells differed in their responses and receptivity to different irradiation regimens, indicating cell line/cell type specificity of the effect. At the end of both therapy concepts, normal and malignant cells reach almost the same endpoint of cell count and proliferation inhibition, confirming the clinical observations in the follow-up at the cellular level. These result in cell lines closely replicating the irradiation schedules in clinical practice and, to some extent, contributing to the understanding of growth rate or remission of tumors and the development of fibrosis.

The Prognostic Value of Liquid Biopsies for Benefit of Salvage Radiotherapy in Relapsed Oligometastatic Prostate Cancer.

To assess the prognostic value of "liquid biopsies" for the benefit of salvage RT in oligometastatic prostate cancer relapse, we enrolled 44 patients in the study between the years 2016 and 2020. All the patients were diagnosed as having an oligometastatic prostate cancer relapse on prostate-specific membrane antigen (PSMA)-targeted PET-CT and underwent irradiation at the Department of Radiotherapy at the Hannover Medical School. Tumor cells and total RNA, enriched from the liquid biopsies of patients, were processed for the subsequent quantification analysis of relative transcript levels in real-time PCR. In total, 54 gene transcripts known or suggested to be associated with prostate cancer or treatment outcome were prioritized for analysis. We found significant correlations between the relative transcript levels of several investigated genes and the Gleason score, PSA (prostate-specific antigen) value, or UICC stage (tumor node metastasis -TNM classification of malignant tumors from Union for International Cancer Control). Furthermore, a significant association of MTCO2, FOXM1, SREBF1, HOXB7, FDXR, and MTRNR transcript profiles was found with a temporary and/or long-term benefit from RT. Further studies on larger patients cohorts are necessary to prove our preliminary findings for establishing liquid biopsy tests as a predictive examination method prior to salvage RT.

Downregulation of miR-1270 mediates endothelial progenitor cell function in preeclampsia: Role for ATM in the Src/VE-cadherin axis.

Preeclampsia, a pregnancy-related hypertensive disorder, is associated with endothelial dysfunction and increased cardiovascular risk of the offspring in adulthood. In preeclampsia, endothelial colony-forming cells (ECFC) are reduced in number and function. Recently, we have shown that miR-1270, which is involved in cancer in vitro proliferation, migration, and tumor progression, is downregulated in fetal ECFC from preeclamptic pregnancies. We now hypothesize that miR-1270 dysregulation contributes to vascular endothelial dysfunction occurring after preeclampsia via ATM (ataxia telangiectasia mutated) overexpression, the key kinase of DNA damage repair. Here, we show that miR-1270 silencing in normal ECFC and downregulation in preeclamptic ECFC are accompanied by an increase in the expression levels of ATM. Furthermore, ATM activation correlates with upregulated tyrosine kinase Src leading to phosphorylation and internalization of VE-cadherin (vascular endothelial-cadherin) which subsequently compromises endothelial barrier permeability and morphodynamic cell parameters. Treatment with specific ATM inhibitors reveals a novel role of ATM upstream of tyrosine kinase Src activation. Subsequently, Src phosphorylation and internalization of VE-cadherin compromise endothelial barrier permeability. Our findings suggest that downregulation of miR-1270 contributes to impaired ECFC function via the associated ATM overexpression, which further identifies ATM as a novel and critical factor for ECFC defects in preeclampsia. Our study provides new insights into the understanding of ECFC impairment associated with cardiovascular risk in preeclamptic offspring and identifies potential novel therapeutic targets.

Genome-wide association study and functional follow-up identify 14q12 as a candidate risk locus for cervical cancer.

Cervical cancer is among the leading causes of cancer-related death in females worldwide. Infection by human papillomavirus (HPV) is an established risk factor for cancer development. However, genetic factors contributing to disease risk remain largely unknown. We report on a genome-wide association study (GWAS) on 375 German cervical cancer patients and 866 healthy controls, followed by a replication study comprising 658 patients with invasive cervical cancer, 1361 with cervical dysplasia and 841 healthy controls. Functional validation was performed for the top GWAS variant on chromosome 14q12 (rs225902, close to PRKD1). After bioinformatic annotation and in silico predictions, we performed transcript analysis in a cervical tissue series of 317 samples and demonstrate rs225902 as an expression quantitative trait locus (eQTL) for FOXG1 and two tightly co-regulated long non-coding RNAs at this genomic region, CTD-2251F13 (lnc-PRKD1-1) and CTD-2503I6 (lnc-FOXG1-6). We also show allele-specific effects of the 14q12 variants via luciferase assays. We propose a combined effect of genotype, HPV status and gene expression at this locus on cervical cancer progression. Taken together, this work uncovers a potential candidate locus with regulatory functions and contributes to the understanding of genetic susceptibility to cervical cancer.

Video Commentary & Machine Learning: Tell Me What You See, I Tell You Who You Are.

BACKGROUND & OBJECTIVE: Teaching and assessment of complex problem solving are a challenge for medical education. Integrating Machine Learning (ML) into medical education has the potential to revolutionize teaching and assessment of these problem-solving processes. In order to demonstrate possible applications of ML to education, we sought to apply ML in the context of a structured Video Commentary (VC) assessment, using ML to predict residents' training level. SETTING: A secondary analysis of multi-institutional, IRB approved study. Participants had completed the VC assessment consisting of 13 short (20-40 seconds) operative video clips. They were scored in real-time using an extensive checklist by an experienced proctor in the assessment. A ML model was developed using TensorFlow and Keras. The individual scores of the 13 video clips from the VC assessment were used as the inputs for the ML model as well as for regression analysis. PARTICIPANTS: A total of 81 surgical residents of all postgraduate years (PGY) 1-5 from 7 institutions constituted the study sample. RESULTS: Scores from individual VC clips were strongly positively correlated with PGY level (p = 0.001). Some video clips were identified to be strongly correlated with a higher total score on the assessment; others had significant influence when used to predict trainees' PGY levels. Using a supervised machine learning model to predict trainees' PGY resulted in a 40% improvement over traditional statistical analysis. CONCLUSIONS: Performing better in a few select video clips was key to obtaining a higher total score but not necessarily foretelling of a higher PGY level. The use of the total score as a sole measure may fail to detect deeper relationships. Our ML model is a promising tool in gauging learners' levels on an assessment as extensive as VC. The model managed to approximate residents' PGY levels with a lower MAE than using traditional statistics. Further investigations with larger datasets are needed.

Genomic Risk Factors for Cervical Cancer.

Cervical cancer is the fourth common cancer amongst women worldwide. Infection by high-risk human papilloma virus is necessary in most cases, but not sufficient to develop invasive cervical cancer. Despite a predicted genetic heritability in the range of other gynaecological cancers, only few genomic susceptibility loci have been identified thus far. Various case-control association studies have found corroborative evidence for several independent risk variants at the 6p21.3 locus (HLA), while many reports of associations with variants outside the HLA region remain to be validated in other cohorts. Here, we review cervical cancer susceptibility variants arising from recent genome-wide association studies and meta-analysis in large cohorts and propose 2q14 (PAX8), 17q12 (GSDMB), and 5p15.33 (CLPTM1L) as consistently replicated non-HLA cervical cancer susceptibility loci. We further discuss the available evidence for these loci, knowledge gaps, future perspectives, and the potential impact of these findings on precision medicine strategies to combat cervical cancer.

Pituitary Tumor Surgery: Comparison of Endoscopic and Microscopic Techniques at a Single Center.

OBJECTIVE: To understand the transition from microscopic surgery (MS) to endoscopic surgery (ES) on the pituitary across the United States, we assessed a single institution practicing both procedures to discern advantages and disadvantages for each. PATIENTS AND METHODS: Retrospective institutional chart review of 534 patients in a large practice over a 6-year period (January 1, 2014, to December 31, 2019) comparing a single MS neurosurgeon with a single ES neurosurgeon operating on the same days. RESULTS: In this series, 14% (n=75) of patients had a prior operation, there were no carotid artery injuries, the overall risk for a postoperative infection was 0.4% (n=2), and risk for a postoperative cerebrospinal fluid leak requiring treatment was 2.0% (n=11). Mean ± SD hospital stay was 1.3±0.04 days; readmission for any reason within 30 days occurred in 3.4% (n=18) of patients. The mean volumetric resection for MS was 86.9%±1.7% and for ES was 91.7%±1.3% (P=.03). There was a higher rate of notable events (P=.015) with MS, but MS had 16% lower cost and operative times were 48 minutes shorter than for ES (83±7 vs 131±6 minutes). The ES required substantially fewer postoperative secondary treatments such as radiation therapy (P=.003). CONCLUSION: Pituitary surgery is a very safe and effective procedure regardless of technique. The MS has shorter operative times and overall lower cost. The ES results in increased volumetric resection and fewer secondary treatments. Both techniques can be valuable to a large practice, and understanding these niches is important when selecting optimal approaches to pituitary surgery for a given patient.

Persistent DNA Double-Strand Breaks After Repeated Diagnostic CT Scans in Breast Epithelial Cells and Lymphocytes.

DNA double-strand break (DSB) induction and repair have been widely studied in radiation therapy (RT); however little is known about the impact of very low exposures from repeated computed tomography (CT) scans for the efficiency of repair. In our current study, DSB repair and kinetics were investigated in side-by-side comparison of RT treatment (2 Gy) with repeated diagnostic CT scans (≤20 mGy) in human breast epithelial cell lines and lymphoblastoid cells harboring different mutations in known DNA damage repair proteins. Immunocytochemical analysis of well known DSB markers γH2AX and 53BP1, within 48 h after each treatment, revealed highly correlated numbers of foci and similar appearance/disappearance profiles. The levels of γH2AX and 53BP1 foci after CT scans were up to 30% of those occurring 0.5 h after 2 Gy irradiation. The DNA damage repair after diagnostic CT scans was monitored and quantitatively assessed by both γH2AX and 53BP1 foci in different cell types. Subsequent diagnostic CT scans in 6 and/or 12 weeks intervals resulted in elevated background levels of repair foci, more pronounced in cells that were prone to genomic instability due to mutations in known regulators of DNA damage response (DDR). The levels of persistent foci remained enhanced for up to 6 months. This "memory effect" may reflect a radiation-induced long-term response of cells after low-dose x-ray exposure.