Utility of Follow-Up Echocardiograms in Uncomplicated Surgical Secundum Atrial Septal Defect Closures: Preliminary Analysis.

INTRODUCTION: Though less common in the current era, surgical closure of secundum atrial septal defects (ASD2) is still performed in certain clinical situations. Guidelines currently recommend lifelong follow-up with transthoracic echocardiograms (TTE) for patients who have undergone a surgical ASD2 closure. The goal of this study was to determine the utility of follow-up TTE in patients who underwent an uncomplicated ASD2 closure. METHODS: Chart review was performed on patients who had a surgical ASD2 closure between April 1, 1996, and August 30, 2021. Patients were excluded if they had other congenital heart disease, had a diagnosis of a residual ASD2, atrial/ventricular arrhythmias, pulmonary hypertension, heart failure, or did not have a follow-up TTE > 6 months after the procedure. The most recent TTEs and clinic notes were evaluated. RESULTS: A total of 30 patients met the criteria. The median age at ASD2 surgery was 4.0 years (IQ; 1.9-10.5). ASD2 was closed via patch repair in 16 patients and primarily closed in 14 patients. The most recent TTE was performed a median of 9.5 years (IQ; 4.0, 14.7) after ASD2 closure. Two patients had mild right atrial and ventricular dilation, one patient had mild right atrial dilation, and one patient had mild right ventricular dilation. All other patients had qualitatively normal right-sided chamber sizes. All patients had normal biventricular function (left ventricular fractional shortening (median 36% (IQ; 33, 42)), no evidence of residual atrial shunts, and no evidence of pulmonary hypertension. No patient was on any cardiac medications at last clinic visit. Four patients were discharged from cardiology clinic and 10 patients were lost to follow-up. There were no deaths. Twenty-four patients had 46 repeat echocardiograms > 1 year after ASD2 with no change in clinical management. CONCLUSION: In patients who underwent an uncomplicated ASD2 closure, there were no significant abnormalities noted on follow-up TTEs. The need for repeat lifetime TTEs and their frequency, in this uncomplicated population, should be reassessed if larger studies with longer follow-up confirm these initial findings.

Design and methods of a translational, community-based, lifestyle weight management pilot intervention trial in breast cancer survivors with overweight or obesity.

Background: Breast cancer survivors (BCS) with overweight or obesity are at heightened risk of cancer recurrence, cardiometabolic disease, and compromised quality of life. Given the prevalence of significant weight gain during and following breast cancer treatment, there is growing recognition of the need to develop efficacious, widely-accessible, weight management programs for BCS. Unfortunately, access to evidence-based weight management resources for BCS remains limited and little is known of the optimal theoretical basis, program components, and mode of delivery for community-based interventions. The primary aim of the Healthy New Albany Breast Cancer (HNABC) pilot trial was to determine the safety, feasibility, and preliminary efficacy of delivering a translational, evidence-based, and theory-driven lifestyle weight management intervention to BCS with overweight or obesity in the community setting. Methods: HNABC was a single-arm, pilot trial evaluating a 24-week, multi-component intervention leveraging exercise, dietary modification, and group-mediated cognitive behavioral (GMCB) counseling components designed to facilitate lifestyle behavior change and promote sustained independent adherence. Assessments of various objectively-determined and patient-reported outcomes and theory-derived determinants of behavioral adoption and maintenance were obtained at baseline, 3- and 6-month follow-up. Measures of trial feasibility were calculated prospectively throughout the study. Conclusion: Findings from the HNABC pilot trial will provide evidence demonstrating the feasibility and preliminary efficacy of a multi-component, community-based, GMCB lifestyle weight management intervention for BCS. Results will inform the design of a future, large-scale, randomized controlled efficacy trial. If successful, this approach could offer a widely accessible, community-based intervention model for weight management programs in BCS.

The feasibility of a telephone-based weight loss intervention in rural Ohio: A pilot study.

BACKGROUND: Weight loss through lifestyle modification can produce health benefits and may reduce cancer risk. The goal of this study was to examine the feasibility of and adherence to a 15-week telephone-based weight loss intervention in rural Ohio, an area with high rates of obesity. METHODS: This pilot 2-arm randomized controlled study was designed for rural Ohio residents who were overweight or obese. Eligible participants were 2:1 randomly assigned to either a 15-week weight loss intervention group or active control group. The weight loss intervention group received weekly telephone sessions to improve healthy diet and increase physical activity. The active control group received education brochures with information on physical activity and dietary guidelines. Feasibility was defined as at least 80% of participants completing the follow-up surveys, and acceptable adherence was defined as the percentage of participants in the weight loss group who attend ≥75% of weekly telephone sessions. RESULTS: A total of 423 individuals entered the online screening survey, 215 (50.8%) completed the survey, and 98 (45.6%) of those were eligible. Forty eligible individuals were enrolled and randomly assigned to the weight loss group (n = 27) or active control group (n = 13). The average age of the weight loss group was 49 (SD = 10) years, and 89% were female. The average age of the active control group was 51 (SD = 9) years, and 92% were female. Feasibility was demonstrated: 90% of participants completed the online follow-up surveys at 15-weeks. Among participants in the weight loss group, 22 out of 27 (81.5%) completed the 15-week intervention, the average number of sessions attended was 9.7 (64.9%). Adherence to the intervention was rated as acceptable among almost half of the group (48.1%). CONCLUSIONS: Feasibility of a 15-week telephone-based weight loss study among rural residents with overweight/obesity were determined. A future study will test this intervention for weight loss efficacy.

Social cognitive outcomes are associated with improvements in mobility performance following lifestyle intervention in prostate cancer patients undergoing androgen deprivation therapy.

OBJECTIVE: To compare the effects of an exercise and dietary intervention with those of standard-of-care management upon change in lift and carry performance and mobility-related self-efficacy beliefs and explore associations in prostate cancer patients undergoing androgen deprivation therapy. METHODS: 32 prostate cancer patients (M age = 66.2 years; SD = 7.8) undergoing androgen deprivation therapy were randomly assigned to a 3-month exercise and dietary lifestyle intervention (n = 16) or standard-of-care management (n = 16). Outcome assessments were obtained at baseline, 2- and 3-month follow-up. RESULTS: The lifestyle intervention resulted in significantly greater improvements in lift and carry performance (p = 0.01) at 2 Months (d = 1.01; p < 0.01) and 3 Months (d = 0.95; p < 0.01) and superior improvements in mobility-related self-efficacy at 2 Months (d = 0.38) and 3 Months (d = 0.58) relative to standard-of-care. Mobility-related self-efficacy (r = -.66; p = 0.006) and satisfaction with function (r = -.63; p = 0.01) were significantly correlated with lift and carry performance at 3 Months. CONCLUSIONS: The exercise and dietary lifestyle intervention yielded superior improvements in lift and carry performance and mobility-related self-efficacy relative to standard-of-care and key social cognitive outcomes were associated with more favorable mobility performance.

Cutting in-line with iron: ribosomal function and non-oxidative RNA cleavage.

Divalent metal cations are essential to the structure and function of the ribosome. Previous characterizations of the ribosome performed under standard laboratory conditions have implicated Mg2+ as a primary mediator of ribosomal structure and function. Possible contributions of Fe2+ as a ribosomal cofactor have been largely overlooked, despite the ribosome's early evolution in a high Fe2+ environment, and the continued use of Fe2+ by obligate anaerobes inhabiting high Fe2+ niches. Here, we show that (i) Fe2+ cleaves RNA by in-line cleavage, a non-oxidative mechanism that has not previously been shown experimentally for this metal, (ii) the first-order in-line rate constant with respect to divalent cations is >200 times greater with Fe2+ than with Mg2+, (iii) functional ribosomes are associated with Fe2+ after purification from cells grown under low O2 and high Fe2+ and (iv) a small fraction of Fe2+ that is associated with the ribosome is not exchangeable with surrounding divalent cations, presumably because those ions are tightly coordinated by rRNA and deeply buried in the ribosome. In total, these results expand the ancient role of iron in biochemistry and highlight a possible new mechanism of iron toxicity.

Root of the Tree: The Significance, Evolution, and Origins of the Ribosome.

The ribosome is an ancient molecular fossil that provides a telescope to the origins of life. Made from RNA and protein, the ribosome translates mRNA to coded protein in all living systems. Universality, economy, centrality and antiquity are ingrained in translation. The translation machinery dominates the set of genes that are shared as orthologues across the tree of life. The lineage of the translation system defines the universal tree of life. The function of a ribosome is to build ribosomes; to accomplish this task, ribosomes make ribosomal proteins, polymerases, enzymes, and signaling proteins. Every coded protein ever produced by life on Earth has passed through the exit tunnel, which is the birth canal of biology. During the root phase of the tree of life, before the last common ancestor of life (LUCA), exit tunnel evolution is dominant and unremitting. Protein folding coevolved with evolution of the exit tunnel. The ribosome shows that protein folding initiated with intrinsic disorder, supported through a short, primitive exit tunnel. Folding progressed to thermodynamically stable ß-structures and then to kinetically trapped α-structures. The latter were enabled by a long, mature exit tunnel that partially offset the general thermodynamic tendency of all polypeptides to form ß-sheets. RNA chaperoned the evolution of protein folding from the very beginning. The universal common core of the ribosome, with a mass of nearly 2 million Daltons, was finalized by LUCA. The ribosome entered stasis after LUCA and remained in that state for billions of years. Bacterial ribosomes never left stasis. Archaeal ribosomes have remained near stasis, except for the superphylum Asgard, which has accreted rRNA post LUCA. Eukaryotic ribosomes in some lineages appear to be logarithmically accreting rRNA over the last billion years. Ribosomal expansion in Asgard and Eukarya has been incremental and iterative, without substantial remodeling of pre-existing basal structures. The ribosome preserves information on its history.

Repeat computed tomography head scan is not indicated in trauma patients taking novel anticoagulation: A multicenter study.

BACKGROUND: The number of trauma patients on prehospital novel oral anticoagulants (NOACs) is increasing. After an initial negative computed tomography of the head (CTH), practice patterns are variable for obtaining repeat CTH to evaluate for delayed intracranial hemorrhage (ICH-d). However, the risks and outcomes of ICH-d for patients on NOACs are unclear. We hypothesized that, for these patients, the incidence of ICH-d is low, similar to that of warfarin, and when it occurs, it does not result in clinically significant worse outcomes. METHODS: Five level 1 trauma centers in Northern California participated in a retrospective review of anticoagulated trauma patients. Patients were included if their initial CTH was negative. Primary outcomes were incidence of ICH-d, neurosurgical intervention, and death. Patient factors associated with the outcome of ICH-d were determined by multivariable regression. RESULTS: From 2016 to 2018, 777 patients met the inclusion criteria (NOAC, n = 346; warfarin, n = 431), 54% of whom received a repeat CTH. Delayed intracranial hemorrhage incidence was 2.3% in the NOAC group and 4% in the warfarin group (p = 0.31). No NOAC patient with ICH-d required neurosurgical intervention or died because of their head injury. Two warfarin patients received neurosurgical intervention, and three died from their head injury. Head Abbreviated Injury Scale ≥3 was associated with increased odds of developing ICH-d (adjusted odds ratio, 32.70; p < 0.01). CONCLUSION: The incidence of ICH-d in patients taking NOAC is low. In this study, patients on NOACs who developed ICH-d after an initial negative CTH did not need neurosurgical intervention or die from their head injury. Repeat CTH in this patient population does not appear necessary. LEVEL OF EVIDENCE: Prognostic/epidemiologic study, level III.Therapeutic, level IV.

Hospital-level intensive care unit admission for patients with isolated blunt abdominal solid organ injury.

BACKGROUND: The optimal level of care for hemodynamically stable patients with isolated blunt hepatic, renal, or splenic injuries (solid organ injuries [SOIs]) is unknown. We sought to characterize interhospital variability in intensive care unit (ICU) admission of such patients and to determine whether greater hospital-level ICU use would be associated with improved outcomes. METHODS: We conducted a retrospective cohort study using the 2015 and 2016 National Trauma Data Bank. We included adult patients with blunt trauma with SOIs with an Abbreviated Injury Scale score of 2 to 4. We excluded patients with other significant injuries, hypotension, or another indication for ICU admission, and hospitals with less than 10 eligible patients. We categorized hospitals into quartiles based on the proportion of eligible patients admitted to an ICU. The primary outcome was a composite of organ failure (cardiac arrest, acute lung injury/acute respiratory failure, or acute kidney injury), infection (sepsis, pneumonia, or catheter-related blood stream infection), or death during hospitalization. RESULTS: Among 14,312 patients at 444 facilities, 7,225 (50%), 5,050 (35%), and 3,499 (24%) had splenic, hepatic, and renal injuries, respectively. The median proportion of ICU use was 44% (interquartile range, 27-59%, range 0-95%). The composite outcome occurred in 180 patients (1.3%), with death in 76 (0.5%), organ failure in 97 (0.7%), and infection in 53 (0.4%). Relative to hospitals with the lowest ICU use (quartile 1), greater hospital-level ICU use was not associated with decreased likelihood of the composite outcome (adjusted odds ratios, 1.31; 95% confidence interval [95% CI], 0.88-1.95; 0.81; 95% CI, 0.52-1.26; and 0.94; 95% CI, 0.62-1.43 for quartiles 2-4, respectively) or its components. Unplanned ICU transfer was no more likely with lower hospital-level ICU use. CONCLUSION: Admission location of stable patients with isolated mild to moderate abdominal SOIs is variable across hospitals, but hospitalization at a facility with greater ICU use is not associated with substantially improved outcomes. LEVEL OF EVIDENCE: Therapeutic/care management, Level IV.

Evolving Strategies to Manage Clostridium difficile Colitis.

Clostridium difficile infection remains a common nosocomial illness with a significant impact on health care delivery. As molecular phenotyping of this organism has changed our understanding of its transmission and virulence, so too have diagnostic methods and treatment strategies evolved in recent years. The burden of this infection falls predominantly on elderly patients with comorbidities who have recently received antibiotics. Oral or enteral vancomycin is now preferred for first-line antimicrobial treatment across the disease spectrum, including mild-moderate initial cases. Fidaxomicin (a novel macrolide antibiotic), bezlotoxumab (a monoclonal antibody against toxin TcdB), and fecal microbiota transplantation expand the therapeutic armamentarium, particularly for recurrent infection. Operative treatment should be reserved for patients with fulminant infection, and early identification of patients who would benefit from an operation remains a challenge. Less invasive surgical options-such as laparoscopic diverting ileostomy with colonic irrigation-may improve survival and other outcomes relative to total abdominal colectomy and represent an attractive alternative particularly for frail patients.

Older Adults With Isolated Rib Fractures Do Not Require Routine Intensive Care Unit Admission.

BACKGROUND: Older adults with isolated rib fractures are often admitted to an intensive care unit (ICU) because of presumedly increased morbidity and mortality. However, evidence-based guidelines are limited. We sought to identify characteristics of these patients that predict the need for ICU care. MATERIALS AND METHODS: We analyzed patients ≥50 y old at our center during 2013-2017 whose only indication for ICU admission, if any, was isolated rib fractures. The primary outcome was any critical care intervention (e.g., intubation) or adverse event (e.g., hypoxemia) (CCIE) based on accepted critical care guidelines. We used stepwise logistic regression to identify characteristics that predict CCIEs. RESULTS: Among 401 patients, 251 (63%) were admitted to an ICU. Eighty-three patients (33%) admitted to an ICU and 7 (5%) admitted to the ward experienced a CCIE. The most common CCIEs were hypotension (10%), frequent respiratory therapy (9%), and oxygen desaturation (8%). Predictors of CCIEs included incentive spirometry <1 L (OR 4.72, 95% CI 2.14-10.45); use of a walker (OR 2.86, 95% CI 1.29-6.34); increased chest Abbreviated Injury Scale score (AIS 3 OR 5.83, 95% CI 2.34-14.50); age ≥72 y (OR 2.68, 95% CI 1.48-4.86); and active smoking (OR 2.11, 95% CI 1.06-4.20). CONCLUSIONS: Routine ICU admission is not necessary for most older adults with isolated rib fractures. The predictors we identified warrant prospective evaluation for development of a clinical decision rule to preclude unnecessary ICU admissions.

Effects of a lifestyle intervention on body composition in prostate cancer patients on androgen deprivation therapy.

Background: Exercise and dietary (EX+D) interventions could represent an optimal treatment for attenuating or reversing adverse effects of androgen deprivation therapy (ADT) in prostate cancer (PCa) patients. The Individualized Diet and Exercise Adherence-Pilot (IDEA-P) trial compared the effects of an EX+D intervention relative to standard-of-care (SC) treatment among PCa patients undergoing ADT. The present study evaluated the effects of the EX+D intervention on body composition (BC) obtained via dual-energy X-ray absorptiometry (DXA) in a subsample of IDEA-P patients. A secondary objective was to explore the association of adiposity and lean mass with mobility performance and strength. Methods: Complete DXA data were acquired from a subsample of 22 PCa patients (EX+D: n = 13; SC: n = 9) at baseline and 3 month follow-up. Intention-to-treat analysis included data from 30 participants (M age = 66.28; SD = 7.79) with baseline DXA assessments. Results: Intention-to-treat analysis revealed EX+D resulted in significant improvements in fat mass (P = 0.022), per cent fat mass (P = 0.028), trunk fat mass (P = 0.017), fat mass/lean mass (P = 0.040), and per cent lean mass (P = 0.026) vs. SC. EX+D also resulted in more favourable changes in appendicular lean mass/body mass (d = 0.59). Select BC outcomes were also significantly correlated with mobility performance and strength (P < 0.05) at 3 month follow-up. Conclusions: Findings suggest the EX+D intervention resulted in superior preservation of lean tissue and improvement in adiposity relative to SC treatment. Results underscore the utility of implementing EX+D interventions for preserving muscle mass and reducing adiposity in PCa patients undergoing ADT.

Effects of a Group-Mediated Cognitive Behavioral Lifestyle Intervention on Select Social Cognitive Outcomes in Prostate Cancer Patients Undergoing Androgen Deprivation Therapy.

Objective. To compare the effects of a group-mediated cognitive behavioral (GMCB) exercise and dietary (EX+D) intervention with those of standard-of-care (SC) treatment on select social cognitive outcomes in prostate cancer (PCa) patients undergoing androgen deprivation therapy (ADT). Methods. In the single-blind, 2-arm, randomized controlled Individualized Diet and Exercise Adherence-Pilot (IDEA-P) trial, 32 PCa patients (mean age = 66.2 years; SD = 7.8) undergoing ADT were randomly assigned to a 12-week EX+D intervention (n = 16) or SC treatment (n = 16). The exercise component of the personalized EX+D intervention integrated a combination of supervised resistance and aerobic exercise performed twice per week. The dietary component involved counseling and education to modify dietary intake and composition. Blinded assessments of social cognitive outcomes were obtained at baseline and 2-month and 3-month follow-up. Results. Intent-to-treat analysis of covariance demonstrated that the EX+D intervention resulted in significantly greater improvements in scheduling (P < .05), coping (P < .01), and exercise self-efficacy (P < .05), and satisfaction with function (P < .01) at 3 months relative to SC. Results of partial correlation analysis also demonstrated that select social cognitive outcomes were significantly correlated with primary trial outcomes of mobility performance and exercise participation (P < .05) at 3-month follow-up. Conclusions: The GMCB lifestyle intervention yielded more favorable improvements in relevant social cognitive outcomes relative to SC among PCa patients undergoing ADT. Additionally, more favorable social cognitive outcomes were associated with superior mobility performance and exercise participation following the independent maintenance phase of the EX+D intervention.

A Rare Case of an Intracardiac Myoepithelial Carcinoma in an Infant.

Myoepithelial carcinomas (MC) represent aggressive tumors that occur in a myriad of ages and anatomic locations. The rarity and histologic similarity with other tumors make them difficult to diagnosis. We report an extremely rare case of a right ventricular outflow tract mass identified to be an intracardiac MC in a 4-month-old male infant. Pathology revealed an EWS-KLF15 translocation. Treatment included gross total resection and intensive chemotherapy. Recurrent cardiac mass with brain metastasis was seen 16 months after primary diagnosis. We describe the rarity of intracardiac MC in pediatric patients and the challenges encountered in the multimodal management of this patient.

Folding, Assembly, and Persistence: The Essential Nature and Origins of Biopolymers.

Life as we know it requires three basic types of polymers: polypeptide, polynucleotide, and polysaccharide. Here we evaluate both universal and idiosyncratic characteristics of these biopolymers. We incorporate this information into a model that explains much about their origins, selection, and early evolution. We observe that all three biopolymer types are pre-organized, conditionally self-complementary, chemically unstable in aqueous media yet persistent because of kinetic trapping, with chiral monomers and directional chains. All three biopolymers are synthesized by dehydration reactions that are catalyzed by molecular motors driven by hydrolysis of phosphorylated nucleosides. All three biopolymers can access specific states that protect against hydrolysis. These protected states are folded, using self-complementary interactions among recurrent folding elements within a given biopolymer, or assembled, in associations between the same or different biopolymer types. Self-association in a hydrolytic environment achieves self-preservation. Heterogeneous association achieves partner-preservation. These universal properties support a model in which life's polymers emerged simultaneously and co-evolved in a common hydrolytic milieu where molecular persistence depended on folding and assembly. We believe that an understanding of the structure, function, and origins of any given type of biopolymer requires the context of other biopolymers.

Abnormal Longitudinal Growth of the Aorta in Children with Familial Bicuspid Aortic Valve.

Bicuspid aortic valve (BAV) is the most common type of congenital heart defect (CHD) and is associated with clinically significant cardiovascular complications including valve calcification and ascending aortopathy (AscAo), predominantly occurring in adulthood. While a limited number of genetic etiologies for BAV have been defined, family members of affected individuals display BAV along with other left-sided CHD. This has led to guidelines from the American Heart Association and American College of Cardiology that recommend echocardiographic screening of first-degree relatives of affected adults. While potentially beneficial in adults, the yield of such screening in children is unknown. The purpose of this study was to investigate a cohort of children with familial BAV to determine the frequency of development of AscAo, and to identify risk factors that contribute to abnormal aortic growth. Echocardiograms over a 10-year follow-up period were reviewed on 26 patients with familial BAV [22 male, 4 female; 22 with isolated BAV, 6 with BAV and aortic coarctation (CoA)]. All had a family history of CHD and were recruited from 2005 to 2010 as part of a genetics research study. Four aortic segments (annulus, root, sinotubular junction, ascending aorta) on parasternal long-axis echocardiographic images were measured by a single observer. The mean age at first echocardiogram was 7.1 ± 5.5 and that was 13.8 ± 6.2 years at the last echocardiogram. Only patients with > 2 echocardiograms in the 10-year period were included. Z score measurements of the aorta were plotted over time and based on these the cohort was divided into two groups: Group 1 (abnormal)-Z score for any segment > 2 or a change in Z score > 2 over follow-up; Group 2 (normal)-Z score < 2 throughout follow-up and change in Z score < 2. Nineteen out of 26 children displayed abnormal aortic growth or dilation of the aorta. BAV with right/left cusp fusion was more frequent in Group 1 (15/18) versus Group 2 (3/7) (p < 0.05). There were no significant differences in gender, aortic valve dysfunction, presence of CoA, family history, cardiac function, presence of left ventricular hypertrophy, or medication use between the 2 groups. In our longitudinal study of children with familial BAV, the majority display evidence of abnormal growth of the ascending aorta during the follow-up period consistent with AscAo and support the extension of current adult guidelines to the pediatric population. While we find that right/left cusp fusion is a risk factor for abnormal aortic growth, additional studies are needed to identify other factors to better select children who require serial screening.

Iron mediates catalysis of nucleic acid processing enzymes: support for Fe(II) as a cofactor before the great oxidation event.

Life originated in an anoxic, Fe2+-rich environment. We hypothesize that on early Earth, Fe2+ was a ubiquitous cofactor for nucleic acids, with roles in RNA folding and catalysis as well as in processing of nucleic acids by protein enzymes. In this model, Mg2+ replaced Fe2+ as the primary cofactor for nucleic acids in parallel with known metal substitutions of metalloproteins, driven by the Great Oxidation Event. To test predictions of this model, we assay the ability of nucleic acid processing enzymes, including a DNA polymerase, an RNA polymerase and a DNA ligase, to use Fe2+ in place of Mg2+ as a cofactor during catalysis. Results show that Fe2+ can indeed substitute for Mg2+ in catalytic function of these enzymes. Additionally, we use calculations to unravel differences in energetics, structures and reactivities of relevant Mg2+ and Fe2+ complexes. Computation explains why Fe2+ can be a more potent cofactor than Mg2+ in a variety of folding and catalytic functions. We propose that the rise of O2 on Earth drove a Fe2+ to Mg2+ substitution in proteins and nucleic acids, a hypothesis consistent with a general model in which some modern biochemical systems retain latent abilities to revert to primordial Fe2+-based states when exposed to pre-GOE conditions.

Functional RNAs: combined assembly and packaging in VLPs.

We describe here a one pot RNA production, packaging and delivery system based on bacteriophage Qß. We demonstrate a method for production of a novel RNAi scaffold, packaged within Qß virus-like particles (VLPs). The RNAi scaffold is a general utility chimera that contains a functional RNA duplex with paired silencing and carrier sequences stabilized by a miR-30 stem-loop. The Qß hairpin on the 5΄ end confers affinity for the Qß coat protein (CP). Silencing sequences can include mature miRNAs and siRNAs, and can target essentially any desired mRNA. The VLP-RNAi assembles upon co-expression of CP and the RNAi scaffold in E. coli. The annealing of the scaffold to form functional RNAs is intramolecular and is therefore robust and concentration independent. We demonstrate dose- and time-dependent inhibition of GFP expression in human cells with VLP-RNAi. In addition, we target the 3΄UTR of oncogenic Ras mRNA and suppress Pan-Ras expression, which attenuates cell proliferation and promotes mortality of brain tumor cells. This combination of RNAi scaffold design with Qß VLP packaging is demonstrated to be target-specific and efficient.

Utilization of Whole Exome Sequencing to Identify Causative Mutations in Familial Congenital Heart Disease.

BACKGROUND: Congenital heart disease (CHD) is the most common type of birth defect with family- and population-based studies supporting a strong genetic cause for CHD. The goal of this study was to determine whether a whole exome sequencing (WES) approach could identify pathogenic-segregating variants in multiplex CHD families. METHODS AND RESULTS: WES was performed on 9 kindreds with familial CHD, 4 with atrial septal defects, 2 with patent ductus arteriosus, 2 with tetralogy of Fallot, and 1 with pulmonary valve dysplasia. Rare variants (<1% minor allele frequency) that segregated with disease were identified by WES, and variants in 69 CHD candidate genes were further analyzed. These selected variants were subjected to in silico analysis to predict pathogenicity and resulted in the discovery of likely pathogenic mutations in 3 of 9 (33%) families. A GATA4 mutation in the transactivation domain, p.G115W, was identified in familial atrial septal defects and demonstrated decreased transactivation ability in vitro. A p.I263V mutation in TLL1 was identified in an atrial septal defects kindred and is predicted to affect the enzymatic functionality of TLL1. A disease-segregating splice donor site mutation in MYH11 (c.4599+1delG) was identified in familial patent ductus arteriosus and found to disrupt normal splicing of MYH11 mRNA in the affected individual. CONCLUSIONS: Our findings demonstrate the clinical utility of WES to identify causative mutations in familial CHD and demonstrate the successful use of a CHD candidate gene list to allow for a more streamlined approach enabling rapid prioritization and identification of likely pathogenic variants from large WES data sets. CLINICAL TRIAL REGISTRATION: URL: https://clinicaltrials.gov; Unique Identifier: NCT0112048.

The ribosome challenge to the RNA world.

An RNA World that predated the modern world of polypeptide and polynucleotide is one of the most widely accepted models in origin of life research. In this model, the translation system shepherded the RNA World into the extant biology of DNA, RNA, and protein. Here, we examine the RNA World Hypothesis in the context of increasingly detailed information available about the origins, evolution, functions, and mechanisms of the translation system. We conclude that the translation system presents critical challenges to RNA World Hypotheses. Firstly, a timeline of the RNA World is problematic when the ribosome is incorporated. The mechanism of peptidyl transfer of the ribosome appears distinct from evolved enzymes, signaling origins in a chemical rather than biological milieu. Secondly, we have no evidence that the basic biochemical toolset of life is subject to substantive change by Darwinian evolution, as required for the transition from the RNA world to extant biology. Thirdly, we do not see specific evidence for biological takeover of ribozyme function by protein enzymes. Finally, we can find no basis for preservation of the ribosome as ribozyme or the universality of translation, if it were the case that other information transducing ribozymes, such as ribozyme polymerases, were replaced by protein analogs and erased from the phylogenetic record. We suggest that an updated model of the RNA World should address the current state of knowledge of the translation system.

Should repair of partial atrioventricular septal defect be delayed until later in childhood?

Surgical repair of partial atrioventricular septal defects (AVSD) has been successful for more than 60 years. However, recent data from the Pediatric Heart Network show that 31% of patients have moderate or severe left atrioventricular valve regurgitation (LAVVR) at follow-up. Previously, our institution found that only 9% of patients had more than moderate LAVVR at the last follow-up. Our objective was to determine the long-term outcomes after repair of partial AVSD in the current era. We reviewed all patients with partial AVSD who had primary biventricular repair from January 1995 to June 2011 at our institution. The Kaplan-Meier method was used to estimate the survival free of an event, and factors were evaluated for an association with each outcome using the log-rank test. All 105 patients with partial AVSD who had surgery during this period were evaluated. The median age at surgery was 7.9 years. The overall survival rate at 1 year was 97%. Median follow-up was 5.3 years (interquartile range 1.7 to 11.1). At 3 years, the survival rate free from reoperation was 89%. Thirteen patients required reoperations with the most common reason being LAVVR. A total of 10 patients developed more than moderate LAVVR with a cumulative incidence of 8% by 2 years. The discrepancy with the Pediatric Heart Network data may be due to the later age of operation for patients in our cohort suggesting that elective repair of partial AVSD should be deferred until children are somewhat older (ages 5 to 8 years). Neither patient age (p = 0.11) nor severity of preoperative LAVVR (p = 0.16) were identified as statistically significant risk factors. In conclusion, there is less morbidity and mortality after surgical repair for partial AVSD.