A small-molecule PI3Kα activator for cardioprotection and neuroregeneration.

Harnessing the potential beneficial effects of kinase signalling through the generation of direct kinase activators remains an underexplored area of drug development1-5. This also applies to the PI3K signalling pathway, which has been extensively targeted by inhibitors for conditions with PI3K overactivation, such as cancer and immune dysregulation. Here we report the discovery of UCL-TRO-1938 (referred to as 1938 hereon), a small-molecule activator of the PI3Kα isoform, a crucial effector of growth factor signalling. 1938 allosterically activates PI3Kα through a distinct mechanism by enhancing multiple steps of the PI3Kα catalytic cycle and causes both local and global conformational changes in the PI3Kα structure. This compound is selective for PI3Kα over other PI3K isoforms and multiple protein and lipid kinases. It transiently activates PI3K signalling in all rodent and human cells tested, resulting in cellular responses such as proliferation and neurite outgrowth. In rodent models, acute treatment with 1938 provides cardioprotection from ischaemia-reperfusion injury and, after local administration, enhances nerve regeneration following nerve crush. This study identifies a chemical tool to directly probe the PI3Kα signalling pathway and a new approach to modulate PI3K activity, widening the therapeutic potential of targeting these enzymes through short-term activation for tissue protection and regeneration. Our findings illustrate the potential of activating kinases for therapeutic benefit, a currently largely untapped area of drug development.

Gene-teratogen interactions influence the penetrance of birth defects by altering Hedgehog signaling strength.

Birth defects result from interactions between genetic and environmental factors, but the mechanisms remain poorly understood. We find that mutations and teratogens interact in predictable ways to cause birth defects by changing target cell sensitivity to Hedgehog (Hh) ligands. These interactions converge on a membrane protein complex, the MMM complex, that promotes degradation of the Hh transducer Smoothened (SMO). Deficiency of the MMM component MOSMO results in elevated SMO and increased Hh signaling, causing multiple birth defects. In utero exposure to a teratogen that directly inhibits SMO reduces the penetrance and expressivity of birth defects in Mosmo-/- embryos. Additionally, tissues that develop normally in Mosmo-/- embryos are refractory to the teratogen. Thus, changes in the abundance of the protein target of a teratogen can change birth defect outcomes by quantitative shifts in Hh signaling. Consequently, small molecules that re-calibrate signaling strength could be harnessed to rescue structural birth defects.

Outcomes Associated With Giant Coronary Artery Aneurysms After Kawasaki Disease: A Single-Center United States Experience.

OBJECTIVE: To determine the long-term outcomes among a cohort of patients with Kawasaki disease (KD) and a history of giant coronary artery aneurysms (CAA) at a single US center. RESULTS: There were 60 patients with KD and giant CAAs identified between 1989 and 2023. The majority of patients were male (71.7%) with median age at diagnosis of 0.9 years (0.2-13.3). Patients were followed for a median of 11 years, up to 34.5 years. MACE occurred in 13 (21.7%) patients at a median of 1.4 years (0.04-22.6) after KD diagnosis. The 10-, 20-, and 30-year MACE-free rates were 75%, 75%, and 60%. Patients with maximal CA z-scores ≥20 or bilateral CAA were more likely to have MACE. During follow-up, 26.7% of CAA regressed to normal luminal diameter at a median of 3.6 years (0.6-12.0). The 10-, 20- and 30-year likelihood of CA regression to normal luminal diameter was 36%, 46%, and 46%. CONCLUSIONS: Over 30 years, MACE occurred in nearly 22% of patients, more often in those with bilateral CAA or CA z-scores ≥20. Despite regression to normal luminal diameter in over 25% of CAA, patients with a history of KD-associated giant CAA require ongoing surveillance for cardiac complications, even years after the initial disease.

Herbal and Non-Herbal Dietary Supplements for Psychiatric Indications: Considerations in Liver Transplantation.

PURPOSE OF REVIEW: Traditional, complementary, and integrative medicine (TCIM) modalities are widely employed. However, TCIM, specifically herbal and non-herbal dietary supplements, can pose challenges in the context of organ transplantation. In this review, we discuss common supplements used for psychiatric purposes and highlight important considerations for candidates and recipients of liver transplants. RECENT FINDINGS: Ashwagandha, kava kava, green tea extract, skullcap, turmeric, and valerian have known idiosyncratic hepatotoxic potential and may complicate the liver transplantation course. Multiple supplements reportedly carry a lower risk of hepatotoxicity, though evidence for widespread use in those at risk for or with hepatic impairment is limited. Psychiatrists caring for candidates and recipients of liver transplants must recognize that patients may find supplements helpful in alleviating psychiatric symptoms, despite an overall limited evidence base. Evaluating benefit versus risk ratios and reviewing drug-drug interactions is essential to promote transplant candidacy and mitigate the possibility of native or graft liver dysfunction.

Analysis of serum microRNA-122 in a randomized controlled trial of N-acetylcysteine for treatment of antituberculosis drug-induced liver injury.

AIM: Serum microRNA-122 (miR-122) is a novel biomarker for drug-induced liver injury, with good sensitivity in the early diagnosis of paracetamol-induced liver injury. We describe miR-122 concentrations in participants with antituberculosis drug-induced liver injury (AT-DILI). We explored the relationship between miR-122 and alanine aminotransferase (ALT) concentrations and the effect of N-acetylcysteine (NAC) on miR-122 concentrations. METHODS: We included participants from a randomized placebo-controlled trial of intravenous NAC in AT-DILI. ALT and miR-122 concentrations were quantified before and after infusion of NAC/placebo. We assessed correlations between ALT and miR-122 concentrations and described changes in ALT and miR-122 concentrations between sampling occasions. RESULTS: We included 45 participants; mean age (± standard deviation) 38 (±10) years, 58% female and 91% HIV positive. The median (interquartile range) time between pre- and post-infusion biomarker specimens was 68 h (47-77 h). The median pre-infusion ALT and miR-122 concentrations were 420 U/L (238-580) and 0.58 pM (0.18-1.47), respectively. Pre-infusion ALT and miR-122 concentrations were correlated (Spearman's ρ = .54, P = .0001). Median fold-changes in ALT and miR-122 concentrations between sampling were 0.56 (0.43-0.69) and 0.75 (0.23-1.53), respectively, and were similar in the NAC and placebo groups (P = .40 and P = .68 respectively). CONCLUSIONS: miR-122 concentrations in our participants with AT-DILI were considerably higher than previously reported in healthy volunteers and in patients on antituberculosis therapy without liver injury. We did not detect an effect of NAC on miR-122 concentrations. Further research is needed to determine the utility of miR-122 in the diagnosis and management of AT-DILI.

Autophagy gene haploinsufficiency drives chromosome instability, increases migration, and promotes early ovarian tumors.

Autophagy, particularly with BECN1, has paradoxically been highlighted as tumor promoting in Ras-driven cancers, but potentially tumor suppressing in breast and ovarian cancers. However, studying the specific role of BECN1 at the genetic level is complicated due to its genomic proximity to BRCA1 on both human (chromosome 17) and murine (chromosome 11) genomes. In human breast and ovarian cancers, the monoallelic deletion of these genes is often co-occurring. To investigate the potential tumor suppressor roles of two of the most commonly deleted autophagy genes in ovarian cancer, BECN1 and MAP1LC3B were knocked-down in atypical (BECN1+/+ and MAP1LC3B+/+) ovarian cancer cells. Ultra-performance liquid chromatography mass-spectrometry metabolomics revealed reduced levels of acetyl-CoA which corresponded with elevated levels of glycerophospholipids and sphingolipids. Migration rates of ovarian cancer cells were increased upon autophagy gene knockdown. Genomic instability was increased, resulting in copy-number alteration patterns which mimicked high grade serous ovarian cancer. We further investigated the causal role of Becn1 haploinsufficiency for oncogenesis in a MISIIR SV40 large T antigen driven spontaneous ovarian cancer mouse model. Tumors were evident earlier among the Becn1+/- mice, and this correlated with an increase in copy-number alterations per chromosome in the Becn1+/- tumors. The results support monoallelic loss of BECN1 as permissive for tumor initiation and potentiating for genomic instability in ovarian cancer.

Comparing weight-based dosing of tacrolimus XR in obese and non-obese renal transplant recipients.

The recommended initial weight-based dose of extended-release (XR) tacrolimus (Envarsus XR) in kidney transplant recipients (KTR) is 0.14 mg/kg/day. However, no data exist regarding dosing recommendations for obese patients specifically. The aim of this study was to evaluate weight-based dosing requirements in a cohort of obese KTR who were initiated on de novo tacrolimus XR post-transplantation. The primary outcome was weight-based dosing requirements (mg/kg/day) on post-operative day (POD) 7 and 14. Of the 254 KTR, 81 (31%) were obese. The median therapeutic dose on POD7 was 0.1 versus 0.12 vs. 0.14 mg/kg/day in the BMI > 30 kg/m2 , BMI 25-30 kg/m2 , and BMI < 25 kg/m2 , respectively, (p = .0001). This result was similar on POD14; median therapeutic dose was 0.09 versus 0.11 versus 0.15 mg/kg/day in the BMI > 30 kg/m2 , BMI 25-30 kg/m2 , and BMI < 25 kg/m2 , respectively, (p < .001). Therapeutic dose on POD7 and POD14 based on ideal body was similar in all cohorts (p = .238, p = .923, respectively). This finding was supported by a strong linear relationship between ideal body weight (IBW) and therapeutic dose (r = .929). In both obese and non-obese KTR, IBW had a stronger correlation with the therapeutic dose for tacrolimus XR.

Efficacy and Safety of Albendazole in Hookworm-infected Preschool-aged Children, School-aged Children, and Adults in Côte d'Ivoire: A Phase 2 Randomized, Controlled Dose-finding Trial.

BACKGROUND: Infections with hookworms affect about half a billion people worldwide. Recommended therapy includes 400 mg of albendazole, which is moderately efficacious. Higher doses have been rarely assessed. METHODS: A randomized, controlled dose-finding trial was conducted in Côte d'Ivoire with the aim of recruiting 120 preschool-aged children (PSAC), 200 school-aged children (SAC), and 200 adults. Eligible PSAC were randomized 1:1:1 to 200 mg, 400 mg, or 600 mg of albendazole; the other age groups were randomized 1:1:1:1:1 to placebo or 200 mg, 400 mg, 600 mg, or 800 mg. The primary outcome was cure rates (CRs) assessed 14-21 days post-treatment by quadruplicate Kato-Katz thick smears. Hyperbolic Emax models were used to determine dose-response. RESULTS: 38 PSAC, 133 SAC, and 196 adults were enrolled. In adults, predicted CRs increased with ascending doses of albendazole, with a CR of 74.9% (95% confidence interval [CI], 55.6%-87.7%) in the 800-mg arm. Observed CRs increased with ascending doses of albendazole reaching a maximum of 94.1% (95% CI, 80.3%-99.3%). In SAC, the predicted dose-response curve increased marginally, with CRs ranging from 64.0% in the 200-mg arm to 76.0% in the 800-mg arm. Sample size in PSAC was considered too small to derive meaningful conclusions. 10.7% and 5.1% of participants reported any adverse event at 3 hours and 24 hours post-treatment, respectively. CONCLUSIONS: A single 800-mg albendazole dose provides higher efficacy against hookworm and is well tolerated in adults and should be considered for community-based strategies targeting adults. For PSAC and SAC, current recommendations suffice. CLINICAL TRIALS REGISTRATION: NCT03527745.

Linkage of resistance-associated substitutions in GT1 sofosbuvir + NS5A inhibitor failures treated with glecaprevir/pibrentasvir.

BACKGROUND & AIMS: Retreatment with glecaprevir/pibrentasvir (G/P) resulted in a rate of sustained virologic response 12 weeks after treatment completion (SVR12) of >90% in HCV genotype 1 (GT1) patients who previously failed a regimen of sofosbuvir plus an NS5A inhibitor (NS5Ai). This study investigated the prevalence and impact of baseline NS3 and NS5A resistance-associated substitutions (RASs) on the efficacy of G/P in prior GT1 sofosbuvir+NS5Ai failures and the persistence of treatment-emergent RASs. METHODS: Longitudinal samples from 177 patients enrolled in a phase IIIb, randomized pragmatic clinical trial were analyzed. Patients without cirrhosis were randomized to 12 or 16 weeks of G/P, and patients with compensated cirrhosis were randomized to G/P and ribavirin for 12 weeks or G/P for 16 weeks. Linkage of RAS was identified using Primer-ID next-generation sequencing at a 15% cut-off. RESULTS: Of 177 patients, 169 (95.5%) were PI-naïve. All 33 GT1b-infected patients achieved SVR12. In GT1a-infected patients, baseline NS5A RASs were prevalent (74.5%, 105/141) but NS3 RASs were uncommon. Baseline NS3 RASs had no impact on G/P efficacy and patients with baseline NS5A RASs showed a numerically but not statistically significantly lower SVR12 rate compared to those without NS5A RASs (89% vs. 97%). SVR12 was achieved in 34 of 35 (97%) patients without NS5A baseline substitution, and 53 of 57 (93%), 35 of 40 (88%), 5 of 8 (63%) with single, double-linked, and triple-linked NS5A substitutions, respectively. Among 13 patients with virologic failure, 4 acquired treatment-emergent NS3 RASs and 10 acquired NS5A RASs. CONCLUSION: Baseline NS5A RASs were highly prevalent. The presence of an increasing number of linked NS5A RASs in GT1a showed a trend in decreasing SVR12 rates, although no specific NS5A RASs or their linkage pattern were associated with lower SVR12 rates. LAY SUMMARY: Direct-acting antivirals have revolutionized the treatment of chronic hepatitis C infection, but treatment failure occurs in some patients. Retreatment of patients who previously failed a regimen consisting of sofosbuvir and an NS5A inhibitor with a regimen of glecaprevir and pibrentasvir (G/P) is >90% effective. Herein, we analyzed samples from these patients and showed that retreatment efficacy with G/P is lower in patients with double- or triple-linked NS5A resistance mutations than in patients with single or no NS5A resistance mutations. CLINICAL TRIAL NUMBER: NCT03092375.

Validity and reliability of the South African Triage Scale in prehospital providers.

BACKGROUND: The South African Triage Scale (SATS) is a validated in-hospital triage tool that has been innovatively adopted for use in the prehospital setting by Western Cape Government (WCG) Emergency Medical Services (EMS) in South Africa. The performance of SATS by EMS providers has not been formally assessed. The study sought to assess the validity and reliability of SATS when used by WCG EMS prehospital providers for single-patient triage. METHODS: This is a prospective, assessment-based validation study among WCG EMS providers from March to September 2017 in Cape Town, South Africa. Participants completed an assessment containing 50 clinical vignettes by calculating the three components - triage early warning score (TEWS), discriminators (pre-defined clinical conditions), and a final SATS triage color. Responses were scored against gold standard answers. Validity was assessed by calculating over- and under-triage rates compared to gold standard. Inter-rater reliability was assessed by calculating agreement among EMS providers' responses. RESULTS: A total of 102 EMS providers completed the assessment. The final SATS triage color was accurately determined in 56.5%, under-triaged in 29.5%, and over-triaged in 13.1% of vignette responses. TEWS was calculated correctly in 42.6% of vignettes, under-calculated in 45.0% and over-calculated in 10.9%. Discriminators were correctly identified in only 58.8% of vignettes. There was substantial inter-rater and gold standard agreement for both the TEWS component and final SATS color, but there was lower inter-rater agreement for clinical discriminators. CONCLUSION: This is the first assessment of SATS as used by EMS providers for prehospital triage. We found that SATS generally under-performed as a triage tool, mainly due to the clinical discriminators. We found good inter-rater reliability, but poor validity. The under-triage rate of 30% was higher than previous reports from the in-hospital setting. The over-triage rate of 13% was acceptable. Further clinically-based and qualitative studies are needed. TRIAL REGISTRATION: Not applicable.

Risk of pump thrombosis and stroke in patients with continuous-flow left ventricular assist devices and gastrointestinal bleeding.

Gastrointestinal (GI) bleeding is a common complication following the placement of continuous-flow left ventricular assist devices (LVADs) in patients with advanced heart failure. Secondary events arising as a result of GI bleeding have not been well-described. Furthermore, attribution of these events to bleeding is complicated by the interruption or de-intensification of antithrombotic therapy, while bleeding is controlled. The purpose of this study was to assess the incidence of pump thrombosis and ischemic stroke in patients with LVADs who experience GI bleeding, while on support. This was a single-center, retrospective, observational cohort study of consecutive patients with LVADs implanted from January 2012 to June 2018. Patients were assigned to comparator groups based on whether they experienced GI bleeding while on LVAD support. The primary endpoint assessed was the composite of pump thrombosis or ischemic stroke. Secondary endpoints assessed included incidence of pump thrombosis or ischemic stroke. A total of 250 patients were included after screening for exclusion criteria, 101 (40.4%) in the GI bleeding group, and 149 (59.6%) in the non-bleeding group. The incidence of pump thrombosis or ischemic stroke was not significantly greater in patients experiencing GI bleeding [23 (22.8%) vs. 21 (14.1%); P = .09]; however, the incidence of ischemic stroke alone was significantly greater [17 (16.8%) vs. 10 (6.7%); P = .01]. We conclude that GI bleeding in LVAD patients may be associated with a greater risk of ischemic stroke.

COVID-19 (SARS-CoV-2) Infection in Pregnancy: A Systematic Review.

INTRODUCTION: To review published studies related to the association of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections with pregnancy, foetal, and neonatal outcomes during coronavirus disease 2019 (COVID-19) pandemic in a systematic manner. METHODS: A comprehensive electronic search was done through PubMed, Scopus, Medline, Cochrane database, and Google Scholar from December 01, 2019, to May 22, 2020, along with the reference list of all included studies. All cohort studies that reported on outcomes of COVID-19 during pregnancy were included. Qualitative assessment of included studies was performed using the Newcastle-Ottawa scale. RESULTS: Upon admission, most pregnant women underwent a low-dose radiation CT scan; the reports of which included unilateral/bilateral pneumonia in most patients. A marked lymphopenia was also noted in many patients with COVID-19. 513 titles were screened, and 22 studies were included, which identified 156 pregnant women with COVID-19 and 108 neonatal outcomes. The most common maternal/foetal complications included intrauterine/foetal distress (14%) and premature rupture of membranes (8%). The neonatal clinical manifestations of COVID-19 commonly included shortness of breath (6%), gastrointestinal symptoms (4%), and fever (3%). CONCLUSION: COVID-19 infection in pregnancy leads to increased risk in pregnancy complications such as preterm birth, PPROM, and may possibly lead to maternal death in rare cases. There is no evidence to support vertical transmission of SARS-CoV-2 infection to the unborn child. Due to a paucity of inconsistent data regarding the impact of COVID-19 on the newborn, caution should be undertaken to further investigate and monitor possible infection in the neonates born to COVID-19-infected mothers.

Pregnancy and cardiac interventions: What are the optimal management options?

Cardiac disease is the leading cause of maternal mortality in the United Kingdom. Major causes of cardiac death in pregnant women include cardiomyopathies, myocardial infarction, ischemic heart disease, and aortic dissection. Uncorrected congenital heart disease and women who have had corrective or palliative surgery may have complicated pregnancies as well. Some women with significant cardiac disease are unable to meet the increased physiological demands of pregnancy. Of these, those who do not respond to medical treatment may require surgical correction such as coronary artery bypass grafting. The risk of cardiac operations for pregnant women is similar to that for nonpregnant women but the fetal mortality rate remains high. Contributing factors to high fetal mortality rates include timing, urgency of operation, and the fetal/fetoplacental response to cardiopulmonary bypass. The aim of this review is to summarize current evidence in utilizing the different management approaches of cardiac issues during pregnancy.

Tracheostomy while on Extracorporeal Membrane Oxygenation: A Comparison of Percutaneous and Open Procedures.

Although the ideal timing of tracheostomy for critically ill patients is controversial, transitioning from an endotracheal tube can be beneficial. Concerns arise for patients under extracorporeal membrane oxygenation (ECMO) support. Studies have described percutaneous and open tracheostomy approaches for critically ill patients but, to our knowledge, have not compared the two specifically in ECMO patients. This study analyzed safety and aimed to identify if there was a difference in major bleeding or other tracheostomy-associated complications. A single-center retrospective cohort study of all patients who received tracheostomy while on ECMO from July 2013 to May 2019 was completed. The primary endpoint was a significant difference in the incidence of a major bleeding adverse event at 48 hours. Secondary endpoints included differences in the incidence of complications (e.g., procedure-related mortality, ECMO decannulation, tracheal/esophageal injury, and pneumothorax/pneumomediastinum) and survival to discharge. A secondary analysis separated the groups further by comparing those with bleeding events and those without. The study included 27 ECMO patients: 16 (59%) in the percutaneous arm and 11 in the open arm. The median number of ECMO days before tracheostomy was 10 vs. 13, respectively. There were no statistically significant differences between the two groups for major bleeding events (percutaneous 44% vs. open 27%, p = .45), procedure-related mortality, or procedure-related complications. Both percutaneous and open tracheostomies in patients on ECMO require a multidisciplinary approach to minimize adverse effects. Major bleeding does occur, but there was no statistically significant correlation between bleeding events and the type of the tracheostomy approach. Thus, both open and percutaneous tracheostomy approaches have a favorable safety profile.

The Effects of Missed Doses of Antibiotics on Hospitalized Patient Outcomes.

BACKGROUND: Missing doses of antibiotics in hospitalized patients is a well-described but inadequately recognized issue. We hypothesized that missing doses of antibiotics decreases quality of care. METHODS: Retrospective study on patients admitted to the Shock Trauma ICU from February to June 2015. Patients prescribed a multidose course of antibiotics were evaluated. A missed antibiotic dose was one ordered but never given (a completely missed dose) or a dose that was not given within an hour before or after the planned time (an off-schedule missed dose). Patient outcomes included a positive culture, ventilator, ICU and hospital length of stay (LOS), and mortality. Multiple statistical methods were used as appropriate; significance was set as P < 0.05. RESULTS: For the 5-mo study period, 280 patients were admitted and 200 met inclusion criteria. Eight percent of patients (16/200) did not miss any antibiotic doses, 39% (77/200) had only off-schedule doses, 2% (4/200) had only completely missed doses, and 51% (103/200) had both off-schedule and completely missed doses. For the 200 patients, 8167 doses were ordered and 2096 (26%) were missed. Adjusting for age, gender, BMI, injury severity score, and doses of antibiotics showed that those who miss doses off-schedule had longer LOS than those who do not miss doses of antibiotics. There was a significant nonlinear relationship between LOS and frequency of early (P-value = 0.02) and late (P-value = 0.01) doses. CONCLUSIONS: To reduce length of hospital stay and optimize quality, methods to improve compliance with antibiotic dosing schedules should be investigated.

Efficacy and safety of ivermectin and albendazole co-administration in school-aged children and adults infected with Trichuris trichiura: study protocol for a multi-country randomized controlled double-blind trial.

BACKGROUND: Soil-transmitted helminthiasis affects almost 2 billion people worldwide in tropical climates. Preventive chemotherapy, using the benzimidazoles (albendazole and mebendazole) is the current main recommended control strategy. Nevertheless, there is limited efficacy of these drugs against hookworm infection and, to a greater extent, against trichuriasis. We describe a protocol for a trial investigating the efficacy and safety of the co-administration of ivermectin and albendazole against trichuriasis. METHODS: A double-blind, placebo-controlled randomized controlled trial will be conducted in three countries (Côte d'Ivoire, Tanzania and Lao PDR) with the aim to determine the efficacy, safety and extended effects of co-administered ivermectin and albendazole compared to standard albendazole monotherapy. We will enroll 600 participants aged 6-60 years in each setting. The primary outcome is cure rate (CR) against Trichuris trichiura infection as assessed by Kato-Katz 14-21 days after treatment. Secondary outcomes include CRs against concomitant soil-transmitted helminth (STH) infections (Ascaris lumbricoides, hookworm and Strongyloides stercoralis) and egg reduction rates (ERRs) against STH at 14-21 days, 180 days and 360 days. Tolerability of treatment, infection status assessed by polymerase chain reaction (PCR), and potential benefits of deworming on nutritional and morbidity indicators will be assessed. The primary analysis will include an available-case set and use logistic regression models adjusted for age, sex and weight. DISCUSSION: This trial will provide robust results on the efficacy and safety of co-administration of ivermectin and albendazole with the aim to better inform WHO recommendations on control of STHs. Furthermore, secondary and explanatory outcomes will provide direct evidence on the extended effects of combination therapy and insight on the relationship between nutrition and morbidity parameters and infection status and intensity. TRIAL REGISTRATION: NCT03527732 (date assigned: 17 May 2018).

Reducing Radiation Exposure in Cardiac Catheterizations for Congenital Heart Disease.

Ionizing radiation exposure is a necessary risk entailed during congenital cardiac catheterizations. The congenital catheterization lab at Yale New Haven Children's Hospital employed quality improvement strategies to minimize radiation exposure in this vulnerable population. In two phases, we implemented six interventions, which included adding and utilizing lower fluoroscopy and digital angiography (DA) doses, increasing staff and physician radiation awareness, focusing on tighter collimation, and changing the default fluoroscopy and DA doses to lower settings. Post-intervention data were collected prospectively for all procedures in the congenital catheterization lab and compared to pre-intervention radiation data collected retrospectively. Radiation exposure was measured in total air kerma (mGy), dose area product per body weight (DAP/kg) (µGy m2/kg), and fluoroscopy time (min). Data were collected for a total of 312 cases. In considering all procedures, the DAP/kg decreased by 67.6% and air kerma decreased by 63%. Fluoroscopy time did not change over the study period. Significant decreases in radiation exposure (DAP/kg) by procedure type were seen for atrial septal defect, patent ductus arteriosus, and transcatheter pulmonary valve procedures with a 45%, 42% and 83% decrease, respectively. Air kerma decreased significantly for ASD and PDA procedures with an 80% and 72% decrease, respectively. When compared to national benchmarks, the median DAP/kg and air kerma for these procedures are lower at our institution. The decreases continue to be sustained 2 years post-interventions. Systems-based interventions can be readily implemented in the congenital cardiac catheterization lab with dramatic and sustainable radiation dose reduction for patients.

A Guide to Bacterial Culture Identification And Results Interpretation.

PURPOSE: To provide a guide to interpreting bacterial culture results. METHODS: Studies were identified via a PubMed literature search (from 1966 to January 2018). Search terms included microbial sensitivity tests, microbial drug resistance, and anti-infective agents/pharmacology. Articles were included if they were published in English. References within identified articles were also reviewed. RESULTS: This paper reviewed core concepts of interpreting bacterial culture results, including timing of cultures, common culture sites, potential for contamination, interpreting the Gram stain, role of rapid diagnostic tests, conventional antibiotic susceptibility testing, and automated testing. CONCLUSION: This guide can assist pharmacists in their role as integral members of the antimicrobial stewardship team in an effort to improve patient care.

Activation of Latent Dihydroorotase from Aquifex aeolicus by Pressure.

Elevated hydrostatic pressure was used to probe conformational changes of Aquifex aeolicus dihydroorotase (DHO), which catalyzes the third step in de novo pyrimidine biosynthesis. The isolated protein, a 45-kDa monomer, lacks catalytic activity but becomes active upon formation of a dodecameric complex with aspartate transcarbamoylase (ATC). X-ray crystallographic studies of the isolated DHO and of the complex showed that association induces several major conformational changes in the DHO structure. In the isolated DHO, a flexible loop occludes the active site blocking the access of substrates. The loop is mostly disordered but is tethered to the active site region by several electrostatic and hydrogen bonds. This loop becomes ordered and is displaced from the active site upon formation of DHO-ATC complex. The application of pressure to the complex causes its time-dependent dissociation and the loss of both DHO and ATC activities. Pressure induced irreversible dissociation of the obligate ATC trimer, and as a consequence the DHO is also inactivated. However, moderate hydrostatic pressure applied to the isolated DHO subunit mimics the complex formation and reversibly activates the isolated subunit in the absence of ATC, suggesting that the loop has been displaced from the active site. This effect of pressure is explained by the negative volume change associated with the disruption of ionic interactions and exposure of ionized amino acids to the solvent (electrostriction). The interpretation that the loop is relocated by pressure was validated by site-directed mutagenesis and by inhibition by small peptides that mimic the loop residues.

Natural History of Contralateral Hypertrophy in Patients with Multicystic Dysplastic Kidneys.

PURPOSE: We evaluated predictive factors for compensatory hypertrophy and renal outcomes in a large cohort of patients with multicystic dysplastic kidneys. MATERIALS AND METHODS: We conducted a retrospective review from 1997 to 2016. Contralateral kidney and multicystic dysplastic kidney length were recorded from all ultrasounds as well as creatinine when available. We used generalized estimating equations to determine predictors of contralateral kidney length. RESULTS: A total of 443 children with multicystic dysplastic kidneys were identified based on sonographic findings and lack of function on nuclear scan. Average followup was 3.2 years (IQR 1.5 to 5.7). Median time to involution in patients diagnosed before age 2 years was 5.5 years (95% CI 3.8-7.0). In all patients the median time to contralateral hypertrophy was 2.7 years (95% CI 2.2-3.3), and 90% of patients manifested contralateral hypertrophy by 10 years. After adjusting for age, gender, multicystic dysplastic kidney side and cohort status for each year of involution after age 2 years, the contralateral kidney grows 0.35 cm longer (95% CI 0.01-0.68, p = 0.04) compared to cases without involution. Patients with contralateral hypertrophy had greater creatinine clearance at followup (83 vs 61 ml per minute, p = 0.07), although this finding was not statistically significant due to limited data. CONCLUSIONS: The majority of children with multicystic dysplastic kidneys will have contralateral hypertrophy by age 3 years. Multicystic dysplastic kidney involution predicts contralateral kidney growth rate after age 2 years. A small cohort of patients with multicystic dysplastic kidneys will not exhibit contralateral hypertrophy and may be at risk for renal insufficiency.