Citations

Abstract Objective Biomagnetic liver susceptometry (BLS) is a noninvasive method to quantify liver iron concentration (LIC). Here we report our findings from a prospective study which validates in vivo LIC from a SQUID biosusceptometer by in vitro LIC in fresh tissue and paraffin-embedded biopsies from patients at risk for iron overload.Materials and Methods LIC was measured by BLS and biopsy. LIC by biopsy were measured in 40 dry weight fresh tissue and paraffin-embedded liver biopsy samples. LIC from biopsies and total iron scores from histology were compared to biosusceptometry. In addition, the wet-to-dry weight ratio was determined.Results Liver iron concentrations measured by BLS and in 40 fresh tissue biopsies were related by a factor of 6.0 ± 0.2 (r2 = 0.88). Similar results were obtained from comparisons with deparaffinized biopsies (6.6±0.3, r2=0.87) and histology (6.7±1.3, r2=0.47). In contrast, a mean wet-to-dry weight ratio of 4.1 ± 0.7 was achieved from biopsies immediately weighed after the biopsy procedure.ConclusionLIC derived from two independent measures, the historical biopsy gold standard and biosusceptometry, were highly correlated. When comparing biosusceptometry with wet weight biopsies, the liver tissue sample size is critical.

Abstract Intratumoral genomic heterogeneity in glioblastoma (GBM) is a barrier to overcoming radiation (RT) resistance. To discover genotype-independent mediators of RT resistance, we correlated RT resistance with the concentration of approximately 700 metabolites across 23 GBM cell lines. Purine metabolites, especially those containing the base guanine, were most correlated with RT resistance. Similarly, increased abundance of tumor purines was associated with decreased survival in GBM patients treated with RT. This relationship is causal. Purine supplementation protected RT-sensitive GBMs from RT and promoted the repair of RT-induced double strand DNA breaks (DSBs). In vitro and in vivo stable isotope tracing confirmed that GBM cell lines and orthotopic patient-derived xenografts primarily generated purines through the de novo synthetic pathway. RT treatment further increased de novo purine synthesis in GBM through signaling via the DNA damage response. Inhibition of de novo GTP synthesis with mycophenolic acid (MPA) sensitized multiple GBM cell lines and neurospheres to RT by slowing the repair of RT-induced DSBs. MPA-induced radiosensitization was GTP-dependent as it was rescued by nucleoside supplementation. Modulating pyrimidine metabolism affected neither RT resistance nor DSB repair, suggesting these GTP-specific effects are due to active signaling rather than its ability to act as a physical substrate for DNA repair and candidate signaling molecules have been identified. These results were recapitulated in vivo with mycophenolate mofetil (MMF), the orally bioavailable FDA-approved prodrug of MPA. MMF potentiated RT efficacy, reduced tumor guanylates and slowed the repair of RT-induced DSBs across multiple models. Because de novo purine synthesis is activated by many of the oncogenic alterations that drive GBM, its inhibition is a promising genotype-independent strategy to overcome GBM RT resistance. We have now begun a clinical trial to determine whether combining MMF and RT is safe and potentially efficacious in patients with GBM.

Abstract Context. —Bioelectronic sensors, which combine microchip and biological components, are an emerging technology in clinical diagnostic testing. An electronic detection platform using DNA biochip technology (eSensor) is under development for molecular diagnostic applications. Owing to the novelty of these devices, demonstrations of their successful use in practical diagnostic applications are limited. Objective. —To assess the performance of the eSensor bioelectronic method in the validation of 6 Epstein-Barr virus–transformed blood lymphocyte cell lines with clinically important mutations for use as sources of genetic material for positive controls in clinical molecular genetic testing. Two cell lines carry mutations in the CFTR gene (cystic fibrosis), and 4 carry mutations in the HFE gene (hereditary hemochromatosis). Design. —Samples from each cell line were sent for genotype determination to 6 different molecular genetic testing facilities, including the laboratory developing the DNA biochips. In addition to the bioelectronic method, at least 3 different molecular diagnostic methods were used in the analysis of each cell line. Detailed data were collected from the DNA biochip output, and the genetic results were compared with those obtained using the more established methods. Results. —We report the successful use of 2 applications of the bioelectronic platform, one for detection of CFTR mutations and the other for detection of HFE mutations. In all cases, the results obtained with the DNA biochip were in concordance with those reported for the other methods. Electronic signal output from the DNA biochips clearly differentiated between mutated and wild-type alleles. This is the first report of the use of the cystic fibrosis detection platform. Conclusions. —Bioelectronic sensors for the detection of disease-causing mutations performed well when used in a “real-life” situation, in this case, a validation study of positive control blood lymphocyte cell lines with mutations of public health importance. This study illustrates the practical potential of emerging bioelectronic DNA detection technologies for use in current molecular diagnostic applications.

Abstract Introduction The prevalence of smoking among Somali Muslim male immigrants residing in Minnesota is estimated at 44%, however smoking reduction is common during the month of Ramadan. This study evaluated the feasibility and impact of a religiously tailored text message intervention delivered during Ramadan to encourage smoking reduction among Somali Muslim men who smoke. Methods Fifty Somali men were recruited. Participants received two text messages per day starting 1 week prior to and throughout the month of Ramadan. Approximately half were religiously tailored and half were about the risks of smoking and benefits of quitting. Smoking behavior was assessed at baseline, and at weeks 4 (end of Ramadan), 8, and 16. Outcomes included feasibility, acceptability, and preliminary impact of the text message intervention on smoking reduction and bioverified abstinence. Results The average age was 41 years. Average time to first cigarette was 1.8 hours at baseline, and 46% of participants smoked menthol cigarettes. Eighteen of 50 participants selected English and 32 selected Somali text messages. Subjects significantly reduced self-reported cigarettes per day (CPD) from 12.4 CPD at baseline to 5.8 CPD at week 16 (p < 0.001). Seven subjects reported quitting at week 16, five completed CO testing, confirming self-reported abstinence. The majority of participants found the cultural and religious references encouraging at the end of the week 16 survey. Conclusions Religiously tailored text messages to decrease smoking are feasible and acceptable to Somali Muslim men who smoke during Ramadan. This intervention for addressing smoking disparities is worthy of further study. Implications Recruitment of Somali Muslim men who smoke is feasible and supports the idea that further studies targeting smoking during Ramadan are practical. Ramadan presents a window of opportunity upon which to build smoking cessation interventions for smokers who identify as Muslim. These preliminary findings suggest that text messaging is a feasible and acceptable intervention strategy, and that religious tailoring was well received. Such an approach may offer potential for addressing smoking disparities among Somali Muslim male smokers. Trial Registration ClinicalTrial.gov: NCT03379142

Objective: This study aims to present a full spectrum of individual patient presentations of pancreatic fistula risk, and to define the utility of mitigation strategies amongst some of the most prevalent, and vulnerable scenarios surgeons encounter. Background: The FRS has been utilized to identify technical strategies associated with reduced CR-POPF incidence across various risk strata. However, risk-stratification using the FRS has never been investigated with greater granularity. By deriving all possible combinations of FRS elements, individualized risk assessment could be utilized for precision medicine purposes. Methods: FRS profiles and outcomes of 5533 PDs were accrued from 17 international institutions (2003–2019). The FRS was used to derive 80 unique combinations of patient “scenarios.” Risk-matched analyses were conducted using a Bonferroni adjustment to identify scenarios with increased vulnerability for CR-POPF occurrence. Subsequently, these scenarios were analyzed using multivariable regression to explore optimal mitigation approaches. Results: The overall CR-POPF rate was 13.6%. All 80 possible scenarios were encountered, with the most frequent being scenario #1 (8.1%) – the only negligible-risk scenario (CR-POPF rate = 0.7%). The moderate-risk zone had the most scenarios (50), patients (N = 3246), CR-POPFs (65.2%), and greatest non-zero discrepancy in CR-POPF rates between scenarios (18-fold). In the risk-matched analysis, 2 scenarios (#59 and 60) displayed increased vulnerability for CR-POPF relative to the moderate-risk zone (both P < 0.001). Multivariable analysis revealed factors associated with CR-POPF in these scenarios: pancreaticogastrostomy reconstruction [odds ratio (OR) 4.67], omission of drain placement (OR 5.51), and prophylactic octreotide (OR 3.09). When comparing the utilization of best practice strategies to patients who did not have these conjointly utilized, there was a significant decrease in CR-POPF (10.7% vs 35.5%, P < 0.001; OR 0.20, 95% confidence interval 0.12–0.33). Conclusion: Through this data, a comprehensive fistula risk catalog has been created and the most clinically-impactful scenarios have been discerned. Focusing on individual scenarios provides a practical way to approach precision medicine, allowing for more directed and efficient management of CR-POPF.

Objective: To describe the clinical characteristics of adolescents with antidepressant treatment-resistant major depressive disorder (MDD) and to examine the utility of the Antidepressant Treatment Record (ATR) in categorizing treatment resistance in this population. Methods: Adolescents with treatment-resistant MDD enrolled in an interventional study underwent a baseline evaluation with the ATR, Children's Depression Rating Scale-Revised (CDRS-R), and Clinical Global Impressions-Severity (CGI-S) scales. Demographic and clinical characteristics were examined with regard to ATR-defined level of resistance (level 1 to ≥3) using analysis of variance and χ 2 tests. Results: In adolescents with treatment-resistant MDD ( N = 97), aged 12–21 years, most were female (65%), white (89%), and had recurrent illness (78%). Patients were severely ill (median CGI-S score of 5), had a mean CDRS-R score of 63 ± 10, and 17.5% had been hospitalized for depression-related symptoms. Fifty-two patients were classified as ATR 1, whereas 32 were classified as ATR level 2 and 13 patients as ≥3, respectively. For increasing ATR-defined levels, illness duration increased from 12.0 (range: 1.5–31.9) to 14.8 (range: 1.8–31.7) to 19.5 (range: 2.5–36.2) months and the likelihood of treatment with serotonin norepinephrine reuptake inhibitors (SNRIs) and dopamine norepinephrine reuptake inhibitors (DNRIs) similarly increased ( p = 0.006 for both SNRIs and DNRIs) as did the likelihood of treatment with mixed dopamine serotonin receptor antagonists (χ 2 = 17, p < 0.001). Conclusions: This study underscores the morbidity and chronicity of treatment-resistant MDD in adolescents. The present characterization of related clinical features describes the use of nonselective serotonin reuptake inhibitors in adolescents with treatment-resistant depression and raises the possibility that those with the greatest medication treatment resistance are less likely to have had recurrent episodes. The study also demonstrates the utility of the ATR in categorizing treatment resistance in adolescents with MDD.

Abstract The “Optimal Liver Iron” range in iron overloaded patients with thalassemia has been established by Olivieri and Brittenham (Blood, 1997) as 1–2.2 mg/g wet weight liver using direct measurement or calculated as 3.2 to 7 mg/g dry liver weight based on a 3.33 correction factor for body water. This report describes the relationship between liver iron concentration (LIC) measured by SQUID biosusceptometry (BLS, wet weight) compared to liver biopsy (dry weight), in patients with thalassemia (THAL) or sickle cell disease (SCD). A total of 38 chronically transfused patients (THAL n=19, SCD n=19) were prospectively assessed for LIC measured by BLS and liver biopsy within 2 month of each other. Most BLS results were submitted to data repository before receiving iron concentration from liver biopsy. LIC was measured by a low temperature SQUID biosusceptometer system (Ferritometer®) under the standardized Hamburg-Torino-Oakland protocol. Iron in fresh tissue and paraffin embedded liver biopsy samples was measured at Mayo clinics by Inductively Coupled Plasma Mass Spectrometer (ICP-MS). Subjects ranged in age from 5 to 40 years (median: 18 y). Median LIC (n=38) measured by SQUID was 1777 (365–4883) [mg/g wet weight], median LIC by biopsy (fresh tissue) was 10861(1854–32864) [mg/g dry weight]. After excluding the subjects with BMI&gt;30 kg/m2 (n=5), the Spearman rank correlation between wet weight LIC assessed by BLS and dry weight LIC from fresh tissue sample measured by ICP-MS was highly significant (RS=0.90, p&lt;0.0001). No significant difference between fresh tissue and paraffin embedded LIC values was observed. The agreement between BLS and fresh tissue biopsy was tested by Bland-Altman plots. After normalization, no significant proportional or zero bias was visible. The 95% limits of agreement between SQUID-BLS and biopsy LIC values were found between −56% (or –6733 μg/g) and 48% (or 7027 μg/g). This kind of agreement is similar to the results achieved with MRI-R2 by St. Pierre et al (Blood, 2005)(–56% and 50%), however, BLS is a totally independent method relying only on the specific magnetic susceptibility of the hemosiderin-ferritin iron complex. The conversion factor between the two methods (LIC by fresh tissue biopsy vs. LIC by BLS) obtained from a weighted linear regression with zero intercept (Marquardt algorithm) was 6.1 ± 0.3 (R2 = 0.86–0.88, cn2 = 2.3–2.6). Using this conversion factor, the recommended “optimal range” for liver iron in patients with thalassemia major should be considered as 6–13.2 mg/g dry weight liver rather than the generally accepted 3.2–7 mg/g dry weight liver.

INTRODUCTION The human cerebral cortex has undergone an extraordinary increase in size and complexity during mammalian evolution. Cortical cell lineages are specified in the embryo, and genetic and epidemiological evidence implicates early cortical development in the etiology of neuropsychiatric disorders such as autism spectrum disorder (ASD), intellectual disabilities, and schizophrenia. Most of the disease-implicated genomic variants are located outside of genes, and the interpretation of noncoding mutations is lagging behind owing to limited annotation of functional elements in the noncoding genome. RATIONALE We set out to discover gene-regulatory elements and chart their dynamic activity during prenatal human cortical development, focusing on enhancers, which carry most of the weight upon regulation of gene expression. We longitudinally modeled human brain development using human induced pluripotent stem cell (hiPSC)–derived cortical organoids and compared organoids to isogenic fetal brain tissue. RESULTS Fetal fibroblast–derived hiPSC lines were used to generate cortically patterned organoids and to compare oganoids’ epigenome and transcriptome to that of isogenic fetal brains and external datasets. Organoids model cortical development between 5 and 16 postconception weeks, thus enabling us to study transitions from cortical stem cells to progenitors to early neurons. The greatest changes occur at the transition from stem cells to progenitors. The regulatory landscape encompasses a total set of 96,375 enhancers linked to target genes, with 49,640 enhancers being active in organoids but not in mid-fetal brain, suggesting major roles in cortical neuron specification. Enhancers that gained activity in the human lineage are active in the earliest stages of organoid development, when they target genes that regulate the growth of radial glial cells. Parallel weighted gene coexpression network analysis (WGCNA) of transcriptome and enhancer activities defined a number of modules of coexpressed genes and coactive enhancers, following just six and four global temporal patterns that we refer to as supermodules, likely reflecting fundamental programs in embryonic and fetal brain. Correlations between gene expression and enhancer activity allowed stratifying enhancers into two categories: activating regulators (A-regs) and repressive regulators (R-regs). Several enhancer modules converged with gene modules, suggesting that coexpressed genes are regulated by enhancers with correlated patterns of activity. Furthermore, enhancers active in organoids and fetal brains were enriched for ASD de novo variants that disrupt binding sites of homeodomain, Hes1, NR4A2, Sox3, and NFIX transcription factors. CONCLUSION We validated hiPSC-derived cortical organoids as a suitable model system for studying gene regulation in human embryonic brain development, evolution, and disease. Our results suggest that organoids may reveal how noncoding mutations contribute to ASD etiology. Summary of the study, analyses, and main results. Data were generated for iPSC-derived human telencephalic organoids and isogenic fetal cortex. Organoids modeled embryonic and early fetal cortex and show a larger repertoire of enhancers. Enhancers could be divided into activators and repressors of gene expression. We derived networks of modules and supermodules with correlated gene and enhancer activities, some of which were implicated in autism spectrum disorders (ASD).

Background and Purpose― We aimed to determine whether low-frequency electric field navigated repetitive transcranial magnetic stimulation to noninjured motor cortex versus sham repetitive transcranial magnetic stimulation avoiding motor cortex could improve arm motor function in hemiplegic stroke patients when combined with motor training. Methods― Twelve outpatient US rehabilitation centers enrolled participants between May 2014 and December 2015. We delivered 1 Hz active or sham repetitive transcranial magnetic stimulation to noninjured motor cortex before each of eighteen 60-minute therapy sessions over a 6-week period, with outcomes measured at 1 week and 1, 3, and 6 months after end of treatment. The primary end point was the percentage of participants improving ≥5 points on upper extremity Fugl-Meyer score 6 months after end of treatment. Secondary analyses assessed changes on the upper extremity Fugl-Meyer and Action Research Arm Test and Wolf Motor Function Test and safety. Results― Of 199 participants, 167 completed treatment and follow-up because of early discontinuation of data collection. Upper extremity Fugl-Meyer gains were significant for experimental ( P <0.001) and sham groups ( P <0.001). Sixty-seven percent of the experimental group (95% CI, 58%–75%) and 65% of sham group (95% CI, 52%–76%) improved ≥5 points on 6-month upper extremity Fugl-Meyer ( P =0.76). There was also no difference between experimental and sham groups in the Action Research Arm Test ( P =0.80) or the Wolf Motor Function Test ( P =0.55). A total of 26 serious adverse events occurred in 18 participants, with none related to the study or device, and with no difference between groups. Conclusions― Among patients 3 to 12 months poststroke, goal-oriented motor rehabilitation improved motor function 6 months after end of treatment. There was no difference between the active and sham repetitive transcranial magnetic stimulation trial arms. Clinical Trial Registration― URL: https://www.clinicaltrials.gov . Unique identifier: NCT02089464.