Harnessing The Pro-Apoptotic Function Of Myc To Improve Therapeutic Responses In Chemoresistant B-Cell Lymphoma

Therapeutic targeting of initiating oncogenes is the mainstay of precision medicine. Considerable efforts have been expended toward silencing MYC, which drives many human cancers including Burkitt lymphomas (BL). Yet, the effects of MYC silencing on standard-of-care therapies are poorly understood. Here we found that inhibition of MYC transcription renders B-lymphoblastoid cells refractory to chemotherapeutic agents. This suggested that in the context of chemotherapy, stabilization of Myc protein could be more beneficial than its inactivation. We tested this hypothesis by pharmacologically inhibiting glycogen synthase kinase 3 (GSK-3), which normally targets Myc for proteasomal degradation. We discovered that chemorefractory BL cell lines responded better to doxorubicin and other anti-cancer drugs when Myc was thus stabilized. In vivo, GSK3 inhibitors (GSK3i) enhanced doxorubicin-induced apoptosis in BL patient-derived xenografts (BL-PDX) as well as in murine MYC-driven lymphoma allografts. This enhancement was accompanied by and required deregulation of several key genes acting in the extrinsic, death receptor-mediated apoptotic pathway. Consistent with this mechanism of action, GSK3i also facilitated lymphoma cell killing by a death ligand TRAIL and by a death receptor agonist mapatumumab. Thus, GSK3i synergizes with both standard chemotherapeutics and direct engagers of death receptors and could improve outcomes in patients with refractory lymphomas

Regulation of Reactive Nitrogen Species (RNS) Metabolism and Resistance Mechanisms in \u3cem\u3eHaemophilus influenzae\u3c/em\u3e: A Dissertation

Haemophilus influenzae encounters niches within the human host that are predicted to differ in availability of oxygen and reactive nitrogen species (RNS: nitrite and nitric oxide), which influence the environmental redox state. Previously reported data has indicated that an altered redox condition could serve as a signal recognized by H. influenzae to optimize its survival within host microenvironments. To elucidate the role of redox signaling in virulence, we examined regulation by the FNR homolog of H. influenzae, whose counterpart in E. coli has been reported to be a direct oxygen sensor and a regulator of genes responsible for RNS metabolism and resistance. Many members of the FNR regulon are subject to coordinated transcriptional control by NarP, a regulator in E. coli that is activated by cognate sensor NarQ in response to environmental nitrite. To study the regulatory activities of FNR and NarQ-NarP in H. influenzae, I targeted a gene predicted to be FNR-regulated, nrfA, which encodes nitrite reductase, a periplasmic cytochrome-c involved in anaerobic respiration. The fnr, narP and nrfA mutants were assayed for nitrite reduction, which implicated the roles of FNR, NarP and NrfA in RNS metabolism. Using Western blot detection of an epitope-tagged reporter protein fused to the endogenous nrf promoter (Pnrf-HA), I demonstrate that FNR and NarP, but not NarQ, are required for full activation of the nrf promoter. Additionally, Pnrf-HA expression increases as oxygen becomes depleted and decreases when exposed to high concentrations of nitrite, implying that the nrfpromoter is modulated by environmental redox signals. FNR of E. coli has been implicated in regulation of resistance mechanisms to a reactive nitrogen species, nitric oxide (NO), which is produced by innate immune cells during infection as a host defense mechanism. A mutant lacking FNR is more sensitive to NO exposure and killing by activated macrophages than wild type H. influenzae after anaerobic pre-growth. Mutants of nrfA and narP have been tested and initial experiments have shown both mutants have a lesser NO sensitivity phenotype as compared to the fnr mutant, suggesting that other factors could be involved in FNR-mediated NO resistance in H. influenzae. Upon examination of potential factors that might be involved to this phenotype, we discovered FNR-regulated gene, ytfE, which contributes to defense against nitrosative stress. The fnr and ytfE mutants are more susceptible to killing by activated macrophages indicating that FNR regulation of ytfE might be important for in vivo infection

The Double Loaded LV: High Prevalence of Hypertensive LVH Preceding the Development of Severe Aortic Stenosis

Background: It is generally assumed that left ventricular hypertrophy (LVH) in aortic stenosis (AS) is a compensatory adaptation to chronic outflow obstruction. However the advent of TAVR has stimulated more focus on AS in older patients, most of whom have antecedent hypertension (HTN). Accordingly our aim was to investigate the interaction between HTN and AS on LV remodeling in contemporary practice. Methods: We studied 33 consecutive patients with AV peak velocity (PV) \u3e2.5 m/s on their initial echo and a PV of \u3e3.5 m/s on a subsequent study performed at least 5 years later. Patients’ demographics and clinical information were collected. Peak intraventricular pressure (IVP, mmHg) was defined as the sum of systolic arterial pressure and peak intraventricular gradient.Data were analyzed using descriptive statistics, paired- samples T test, and linear correlation. Results: Of our sample (46% women, mean age of 82±11 y), 29 (88%) had a history of hypertension. The average interval between the two echo studies was 6.2±1 years. As expected, wall thickness, LV Mass, and relative wall thickness increased over time. There was no correlation between change in LV mass index (LVMi, g/m2) and peak IVP, PV or AV MG. However change in LVMi did correlate inversely with baseline LVMi (r= -0.37, p= 0.03). Conclusion: Most patients seen in our practice with severe AS have antecedent hypertension and LVH. LVH worsens in parallel with worsening severity of AS. Remodeling in these patients features increasing concentric remodeling of the LV, rather than LV dilation. Given these findings, we speculate that regression of LVH to normal will not be effected by AVR because LVH proceeded hemodynamically severe AS. Strict control of blood pressure might be of equal importance in preventing and ameliorating pressure overload in these patients

Psychometric assessment of the Temptations to Try Alcohol Scale

Effective interventions require an understanding of the behaviors and cognitions that facilitate positive change as well as the development of psychometrically sound measures. This paper reports on the psychometric properties of the Temptations to Try Alcohol Scale (TTAS), including factorial invariance across different subgroups. Data were collected from 3565 6th grade RI middle school students. Structural equation modeling was used to determine the appropriate factorial invariance model for the 9-item TTAS. The measure consists of three correlated subscales: Social Pressure, Social Anxiety, and Opportunity. Three levels of invariance, ranging from the least to the most restrictive, were examined: Configural Invariance, which constrains only the factor structure and zero loadings; Pattern Identity Invariance, which requires factor loadings to be equal across the groups; and Strong Factorial Invariance, which requires factor loadings and error variances to be constrained. Separate analyses evaluated the invariance across two levels of gender (males vs. females), race (white vs. black) ethnicity (Hispanic vs. Non-Hispanic) and school size (small, meaning \u3c 200 6th graders, or large). The highest level of invariance, Strong Factorial Invariance, provided a good fit to the model for gender (CFI: .95), race (CFI: .94), ethnicity (CFI: .94), and school size (CFI: .97). Coefficient Alpha was .90 for Social Pressure, .81 for Social Anxiety, and .82 for Opportunity. These results provide strong empirical support for the psychometric structure and construct validity of the TTAS in middle school students

Prevention of smoking in Middle School Students: Psychometric assessment of the Temptations to Try Smoking Scale

Establishment of psychometrically sound measures is critical to the development of effective interventions. The current study examined the psychometric properties, including factorial invariance, of a six item Temptations to Try Smoking Scale on a sample of middle school students. The sample of 6th grade students (N = 3527) was from 20 Rhode Island middle schools and was 52% male and 84% white. The Temptations to Try Smoking Scale consisted of two correlated subscales: Positive Social and Curiosity/Stress. Structural equation modeling was implemented to evaluate the factorial invariance across four different subgroups defined by gender (male/female), race (white/black), ethnicity (Hispanic/Non-Hispanic), and school size (\u3c 200/ \u3e 200 6th graders). A model is factorially invariant when the measurement model is the same in each of the subgroups. Three levels of invariance were examined in sequential order: 1) Configural Invariance (unconstrained nonzero factor loadings); 2) Pattern Identity Invariance (equal factor loadings); and 3) Strong Factorial Invariance (equal factor loadings and measurement errors). Strong Factorial Invariance provided a good fit to the model across gender (CFI = .96), race (CFI = .96), ethnicity (CFI = .94), and school size (CFI = .97). Coefficient Alphas for the two subscales, Positive Social and Curiosity/Stress, were .87 and .86, respectively. These findings provide empirical support for the construct validity of the Temptations to Try Smoking Scale in middle school students

Prevention of alcohol use in middle school students: Psychometric assessment of the decisional balance inventory

A measurement model should be equivalent across the different subgroups of a target population. The Decisional Balance Inventory for the Prevention of Alcohol Use is a 2-factor correlated model with 3 items for Pros of alcohol use and 3 items for Cons. The measure is part of a tailored intervention for middle school students. This study evaluated the important psychometric assumptions of factorial invariance and scale reliability with a large sample of sixth grade students (N = 3565) from 20 schools. A measure is factorially invariant when the model is the same across subgroups. Three levels of invariance were assessed, from least restrictive to most restrictive: 1) Configural Invariance (unconstrained nonzero factor loadings); 2) Pattern Identity Invariance (equal factor loadings); and 3) Strong Factorial Invariance (equal factor loadings and measurement errors). Structural equation modeling was used to assess invariance over two levels of gender (male and female), race (white and black), ethnicity (Hispanic and non-Hispanic), and school size (large, indicating \u3e 200 students per grade, or small). The strongest level of invariance, Strong Factorial Invariance, was a good fit for the model across all of the subgroups: gender (CFI: 0.94), race (CFI: 0.96), ethnicity (CFI: 0.93), and school size (CFI: 0.97). Coefficient alpha was 0.61 for the Pros and 0.67 for Cons. Together, invariance and reliability provide strong empirical support for the validity of the measure

Need for better and broader training in cardio-obstetrics: A national survey of cardiologists, cardiovascular team members, and cardiology fellows in training

Background Team-based models of cardio-obstetrics care have been developed to address the increasing rate of maternal mortality from cardiovascular diseases. Cardiovascular clinician and trainee knowledge and comfort with this topic, and the extent of implementation of an interdisciplinary approach to cardio-obstetrics, are unknown. Methods and Results We aimed to assess the current state of cardio-obstetrics knowledge, practices, and services provided by US cardiovascular clinicians and trainees. A survey developed in conjunction with the American College of Cardiology was circulated to a representative sample of cardiologists (N=311), cardiovascular team members (N=51), and fellows in training (N=139) from June 18, 2020, to July 29, 2020. Knowledge and attitudes about the provision of cardiovascular care to pregnant patients and the prevalence and composition of cardio-obstetrics teams were assessed. The widest knowledge gaps on the care of pregnant compared with nonpregnant patients were reported for medication safety (42%), acute coronary syndromes (39%), aortopathies (40%), and valvular heart disease (30%). Most respondents (76%) lack access to a dedicated cardio-obstetrics team, and only 29% of practicing cardiologists received cardio-obstetrics didactics during training. One third of fellows in training reported seeing pregnant women 0 to 1 time per year, and 12% of fellows in training report formal training in cardio-obstetrics. Conclusions Formalized training in cardio-obstetrics is uncommon, and limited access to multidisciplinary cardio-obstetrics teams and large knowledge gaps exist among cardiovascular clinicians. Augmentation of cardio-obstetrics education across career stages is needed to reduce these deficits. These survey results are an initial step toward developing a standard expectation for clinicians\u27 training in cardio-obstetrics

Aberrant Intrinsic Activity and Connectivity in Cognitively Normal Parkinson’s Disease

Disturbances in intrinsic activity during resting-state functional MRI (rsfMRI) are common in Parkinson’s disease (PD), but have largely been studied in a priori defined subnetworks. The cognitive significance of abnormal intrinsic activity is also poorly understood, as are abnormalities that precede the onset of mild cognitive impairment. To address these limitations, we leveraged three different analytic approaches to identify disturbances in rsfMRI metrics in 31 cognitively normal PD patients (PD-CN) and 30 healthy adults. Subjects were screened for mild cognitive impairment using the Movement Disorders Society Task Force Level II criteria. Whole-brain data-driven analytic approaches first analyzed the amplitude of low-frequency intrinsic fluctuations (ALFF) and regional homogeneity (ReHo), a measure of local connectivity amongst functionally similar regions. We then examined if regional disturbances in these metrics altered functional connectivity with other brain regions. We also investigated if abnormal rsfMRI metrics in PD-CN were related to brain atrophy and executive, visual organization, and episodic memory functioning. The results revealed abnormally increased and decreased ALFF and ReHo in PD-CN patients within the default mode network (posterior cingulate, inferior parietal cortex, parahippocampus, entorhinal cortex), sensorimotor cortex (primary motor, pre/post-central gyrus), basal ganglia (putamen, caudate), and posterior cerebellar lobule VII, which mediates cognition. For default mode network regions, we also observed a compound profile of altered ALFF and ReHo. Most regional disturbances in ALFF and ReHo were associated with strengthened long-range interactions in PD-CN, notably with regions in different networks. Stronger long-range functional connectivity in PD-CN was also partly expanded to connections that were outside the networks of the control group. Abnormally increased activity and functional connectivity appeared to have a pathological, rather than compensatory influence on cognitive abilities tested in this study. Receiver operating curve analyses demonstrated excellent sensitivity (≥90%) of rsfMRI variables in distinguishing patients from controls, but poor accuracy for brain volume and cognitive variables. Altogether these results provide new insights into the topology, cognitive relevance, and sensitivity of aberrant intrinsic activity and connectivity that precedes clinically significant cognitive impairment. Longitudinal studies are needed to determine if these neurocognitive associations presage the development of future mild cognitive impairment or dementia

Improving Care of Patients At-Risk for Osteoporosis: A Randomized Controlled Trial

BACKGROUND: Despite accurate diagnostic tests and effective therapies, the management of osteoporosis has been observed to be suboptimal in many settings. We tested the effectiveness of an intervention to improve care in patients at-risk of osteoporosis. DESIGN: Randomized controlled trial. PARTICIPANTS: Primary care physicians and their patients at-risk of osteoporosis, including women 65 years and over, men and women 45 and over with a prior fracture, and men and women 45 and over who recently used ≥90 days of oral glucocorticoids. INTERVENTION: A multifaceted program of education and reminders delivered to primary care physicians as well as mailings and automated telephone calls to patients. Outcome: Either undergoing a bone mineral density (BMD) testing or filling a prescription for a bone-active medication during the 10 months of follow-up. RESULTS: After the intervention, 144 (14%) patients in the intervention group and 97 (10%) patients in the control group received either a BMD test or filled a prescription for an osteoporosis medication. This represents a 4% absolute increase and a 45% relative increase (95% confidence interval 9–93%, p = 0.01) in osteoporosis management between the intervention and control groups. No differences between groups were observed in the incidence of fracture. CONCLUSION: An intervention targeting primary care physicians and their at-risk patients increased the frequency of BMD testing and/or filling prescriptions for osteoporosis medications. However, the absolute percentage of at-risk patients receiving osteoporosis management remained low