Sorting for secreted molecule production using a biosensor-in-microdroplet approach.

Sorting large libraries of cells for improved small molecule secretion is throughput limited. Here, we combine producer/secretor cell libraries with whole-cell biosensors using a microfluidic-based screening workflow. This approach enables a mix-and-match capability using off-the-shelf biosensors through either coencapsulation or pico-injection. We demonstrate the cell type and library agnostic nature of this workflow by utilizing single-guide RNA, transposon, and ethyl-methyl sulfonate mutagenesis libraries across three distinct microbes (Escherichia coli, Saccharomyces cerevisiae, and Yarrowia lipolytica), biosensors from two organisms (E. coli and S. cerevisiae), and three products (triacetic acid lactone, naringenin, and L-DOPA) to identify targets improving production/secretion.

Evaluating the usefulness of a wordless picture book for adults with intellectual disabilities about the COVID-19 vaccination programme using co-production: The CAREVIS study.

AIM: To explore the usefulness of a co-designed wordless book showing processes of receiving COVID-19 vaccines designed by, and for, adults with intellectual disabilities. METHODS: A qualitative evaluation of the resource using mixed methods. Semi-structured interviews were conducted with people with intellectual disabilities, carers and health professionals about resource content, and use. This was analysed thematically. A survey was circulated to intellectual disabilities networks to understand resource need, use, sharing and content. RESULTS: Understanding the COVID-19 vaccine was a process, not a single event using one resource. A visual resource had a place in facilitating conversations about vaccines between people with intellectual disabilities and carers. Differing perspectives were expressed regarding personal needs, existing awareness of vaccine programmes and communication preferences. Changes were suggested to improve the suggested storyline and relevance around COVID-19 restrictions changing. CONCLUSION: A visual resource may help conversations about the COVID-19 vaccine for people with intellectual disabilities.

Adaptations to research within the intellectual disability population during the COVID-19 pandemic: Lessons learned from the CAREVIS study.

The COVID-19 pandemic resulted in changes in all areas of clinical practice, including clinical research and within the intellectual disability population. While there have been some benefits from this rapid adoption of change, those involved in research have had to overcome a number of additional challenges. These adaptive changes, which have included the use of technology, closure of social spaces, working with specific groups who are more vulnerable to COVID-19, and mask use impairing communication, have had both positive and negative impacts on research. As the pandemic and related restrictions evolve, it is important to examine the changes that have occurred. In the future, the adoption of a hybrid model in research is likely to be a common approach, establishing a balance between technology and in-person interaction.

Practices and Outcomes from a Prospective, Multicenter Registry for Preterm Newborns with Pulmonary Hypertension.

OBJECTIVE: To describe current treatment practices of preterm infants with early hypoxemic respiratory failure (HRF) and pulmonary hypertension (PH) and their association with patient outcomes. STUDY DESIGN: We developed a prospective, observational, multicenter clinical registry of preterm newborns <34 weeks' gestation with HRF and PH, based on either clinical or echocardiographic evidence during the first 72 hours of life, from 28 neonatal intensive care units in the US from 2017 through 2022. The primary end point was mortality among those who did or did not receive PH-targeted treatment, and the secondary end points included comparisons of major morbidities. Variables were compared using t tests, Wilcoxon rank-sum tests, Fisher exact tests, and χ² tests. RESULTS: We analyzed the results of 224 preterm infants enrolled in the registry. Of which, 84% (188/224) received PH-targeted treatment, most commonly inhaled nitric oxide (iNO). Early mortality in this cohort was high, as 33% (71/224) of this sample died in the first month of life, and 77% of survivors (105/137) developed bronchopulmonary dysplasia. Infants who received PH-targeted treatment had higher oxygenation indices at the time of enrollment (28.16 [IQR: 13.94, 42.5] vs 15.46 [IQR: 11.94, 26.15]; P = .0064). Patient outcomes did not differ between those who did or did not receive PH-targeted therapy. CONCLUSIONS: Early-onset HRF with PH in preterm infants is associated with a high early mortality and a high risk of developing bronchopulmonary dysplasia. iNO is commonly used to treat early-onset PH in preterm infants with HRF. In comparison with untreated infants with lower oxygenation indices, iNO treatment in severe PH may prevent poorer outcomes.

Prevalence and Predictors of Pediatric COVID-19 Vaccine Acceptance.

OBJECTIVE: As pediatric COVID-19 vaccine eligibility expands, understanding predictors of vaccine intent is critical to effectively address parental concerns. Objectives included: (1) Evaluate maternal COVID-19 vaccine intent for child(ren) and associated predictors of stated intent; (2) Describe attitudes related to hypothetical vaccination policies; (3) Summarize themes associated with intention to vaccinate child(ren) for COVID-19. STUDY DESIGN: Mothers enrolled in Heath eMoms, a longitudinal survey project, were recruited for this electronic COVID-19 survey. Chi-square analysis was used to compare proportions of respondent characteristics based on vaccination intent. Population survey logistic regression was used for multivariable modeling to assess the independent association between vaccine intent and demographics. RESULTS: The response rate was 65.3% (n = 1884); 44.2% would choose vaccination, 20.3% would not choose vaccination, and 35.5% are unsure whether to have their child(ren) vaccinated for COVID-19. Black mothers (AOR 0.26, 95% CI 0.13, 0.54), respondents with less than high school education (AOR 0.26, 95% 0.12, 0.56) and those in rural areas (AOR 0.28, 95% CI 0.16, 0.48) were less likely to choose vaccination. Commonly cited reasons for vaccine hesitancy include the belief that the vaccine was not tested enough, is not safe, and there are concerns regarding its side effects. CONCLUSION: Over 50% of respondents do not intend or are unsure about their intent to vaccinate their child(ren) for COVID-19 with variability noted by demographics. Opportunities exist for perinatal and pediatric providers to educate pregnant people, parents, and caregivers with a focus on addressing concerns regarding vaccine safety and efficacy. KEY POINTS: · COVID-19 vaccination rates remain suboptimal, especially in the pediatric population, with variation across states.. · We found that the prevalence of vaccine acceptance for young children is low.. · We highlight opportunities for providers to educate parents, focusing on addressing vaccine safety and efficacy..

Clinical and Financial Impact of a Diagnostic Stewardship Program for Children with Suspected Central Nervous System Infection.

OBJECTIVE: To investigate the optimal implementation and clinical and financial impacts of the FilmArray Meningitis Encephalitis Panel (MEP) multiplex polymerase chain reaction testing of cerebrospinal fluid (CSF) in children with suspected central nervous system infection. STUDY DESIGN: A pre-post quasiexperimental cohort study to investigate the impact of implementing MEP using a rapid CSF diagnostic stewardship program was conducted at Children's Hospital Colorado (CHCO). MEP was implemented with electronic medical record indication selection to guide testing to children meeting approved use criteria: infants <2 months, immunocompromised, encephalitis, and ≥5 white blood cells/µL of CSF. Positive results were communicated with antimicrobial stewardship real-time decision support. All cases with CSF obtained by lumbar puncture sent to the CHCO microbiology laboratory meeting any of the 4 aforementioned criteria were included with preimplementation controls (2015-2016) compared with postimplementation cases (2017-2018). Primary outcome was time-to-optimal antimicrobials compared using log-rank test with Kaplan-Meier analysis. RESULTS: Time-to-optimal antimicrobials decreased from 28 hours among 1124 preimplementation controls to 18 hours (P < .0001) among 1127 postimplementation cases (72% with MEP testing conducted). Postimplementation, time-to-positive CSF results was faster (4.8 vs 9.6 hours, P < .0001), intravenous antimicrobial duration was shorter (24 vs 36 hours, P = .004), with infectious neurologic diagnoses more frequently identified (15% vs 10%, P = .03). There were no differences in time-to-effective antimicrobials, hospital admissions, antimicrobial starts, or length of stay. Costs of microbiologic testing increased, but total hospital costs were unchanged. CONCLUSIONS: Implementation of MEP with a rapid central nervous system diagnostic stewardship program improved antimicrobial use with faster results shortening empiric therapy. Routine MEP testing for high-yield indications enables antimicrobial optimization with unchanged overall costs.

Human placental lipid content and lipid metabolic enzyme abundance in obesity and across gestation.

Changes in placental lipid metabolism influence the delivery of lipids critical for fetal development and fetal requirements for lipids change across gestation. We hypothesized that placental lipid content and metabolic enzyme protein levels increase across gestation and are elevated in obesity. Placentas (4-40 weeks' gestation) were collected from control (body mass index, BMI = 18.5-24.9, n=37) and obese (BMI > 30, n=19) pregnant women. Trophoblast villous tissue was homogenized and subjected to liquid chromatography tandem mass spectrometry (LC-MS/MS) for phospholipid and triacylglycerol (TAG) analysis and western blot for protein quantification. The placental content of TAG species and nine of 35 identified phosphatidylcholines (PC) were significantly higher (P<0.05) in first trimester (28-79%, 10-47%, respectively). Furthermore, two TAG and three PC differed by maternal BMI and were significantly increased (P<0.05) in the obese group in first trimester (72-87%, 88-119%, respectively). Placental protein abundance of glycerol-2-phosphate (GPAT3) and 1-acyl-sn-glycerol-3-phosphate acyltransferase 2 (AGPAT2), involved in de novo synthesis of PC and TAG, were higher (P<0.05) in the first trimester (66 and 74%, respectively). The protein abundance of the PC-remodeling enzyme PLA2G4c was also higher (63%) in first trimester (P<0.05). In conclusion, the placental content of many phospholipid and TAG species and the protein level of associated synthesis enzymes are higher in first-trimester human placenta. The high PC content may be related to the rapid membrane expansion in early pregnancy and the low placental oxygen tension may promote the accumulation of tissue TAGs in first trimester. Maternal obesity had only limited impact on placental lipid content and metabolic enzyme protein abundance.

Placental proteins with predicted roles in fetal development decrease in premature infants.

BACKGROUND: Emerging evidence from animal experiments indicate that factors secreted by the placenta are critical for normal fetal organ development. Our objective was to characterize the umbilical vein and artery proteome in preterm infants and identify proteins that decrease in the neonatal circulation following delivery. METHODS: Cord blood at delivery and neonatal blood at 48-72 h of life was collected in 25 preterm infants. Plasma protein abundance was determined using the SomaLogic platform. RESULTS: When comparing protein levels of umbilical venous to arterial cord blood, 434 proteins were significantly higher indicating placental secretion into the fetal circulation. Moreover, when comparing neonatal blood to umbilical vein levels, 142 proteins were significantly lower. These proteins included Endoplasmic reticulum resident protein 29, CD59, Fibroblast growth factor 2 and Dynactin subunit 2, which are involved in brain development and prevention of brain damage as well as Fibroblast growth factor 1 which prevents lung fibrosis. CONCLUSIONS: The late second trimester human placenta secretes proteins into the fetal circulation which decrease following delivery. Many of these proteins are predicted to be important in the development of fetal organs. Further studies are needed to directly link placental proteins to organ development and poor outcomes in preterm infants. IMPACT: Prematurity remains a leading cause of morbidity and mortality requiring the development of novel treatments. Emerging evidence from animal studies suggest that factors secreted from the placenta may be critical in the development of the fetus. We report that the preterm human placenta secretes an array of proteins into the fetal circulation. Some of these proteins are predicted to be involved in the development of the brain and the lung. When born prematurely, infants are deprived of these placental proteins, which may contribute to their poor outcomes.

Toxicity Induced by a Bispecific T Cell-Redirecting Protein Is Mediated by Both T Cells and Myeloid Cells in Immunocompetent Mice.

Bispecific T cell engagers have demonstrated clinical efficacy; however, their use can be accompanied by severe toxicity. Mechanistic understanding of these toxicities is limited by a lack of suitable immunocompetent preclinical models. In this study, we describe an immunocompetent mouse tumor model that exhibits bispecific T cell engager-induced toxicity and recapitulates key features similar to those in human cytokine release syndrome. In this study, toxicity occurred between the second and fourth injections of an NK Group 2D bispecific T cell engager protein. Symptoms were transient, peaking 3-4 h after treatment and resolving by 8 h. Mice developed weight loss, elevated plasma cytokines, a significant reduction in spleen white pulp, and lymphocyte infiltration in the liver. Systemic cellular immune changes also occurred; notably, an increase in CD8+ T cell activation, an increase in myeloid cells in the blood, and a population of Ly-6Cint monocytes (CD11b+Ly-6G-F4/80-) emerged in the liver and spleens of bispecific protein-treated mice. IFN-γ was primarily produced by CD8+ T cells in the spleen and was required for the observed changes in both T cell and myeloid populations. Rag deficiency, IFN-γ deficiency, or depletion of either CD4+ or CD8+ T cells prevented toxicity, whereas perforin deficiency, GM-CSF deficiency, or modulation of the myeloid population through clodronate-mediated depletion showed a partial abrogation of toxicity. Together, these findings reveal that T cell activation by a bispecific T cell engager leads to changes in the host myeloid cell population, both of which contribute to treatment induced toxicity in immunocompetent mice.

Shifting the distribution: modulation of the lipid profile in Yarrowia lipolytica via iron content.

Microbial fermentation offers a sustainable source of fuels, commodity chemicals, and pharmaceuticals, yet strain performance is influenced greatly by the growth media selected. Specifically, trace metals (e.g., iron, copper, manganese, zinc, and others) are critical for proper growth and enzymatic function within microorganisms yet are non-standardized across media formulation. In this work, the effect of trace metal supplementation on the lipid production profile of Yarrowia lipolytica was explored using tube scale fermentation followed by biomass and lipid characterization. Addition of iron (II) to the chemically defined Yeast Synthetic Complete (YSC) medium increased final optical density nearly twofold and lipid production threefold, while addition of copper (II) had no impact. Additionally, dose-responsive changes in lipid distribution were observed, with the percent of oleic acid increasing and stearic acid decreasing as initial iron concentration increased. These changes were reversible with subsequent iron-selective chelation. Use of rich Yeast Peptone Dextrose (YPD) medium enabled further increases in the production of two specialty oleochemicals ultimately reaching 63 and 47% of the lipid pool as α-linolenic acid and cyclopropane fatty acid, respectively, compared to YSC medium. Selective removal of iron (II) natively present in YPD medium decreased this oleochemical production, ultimately aligning the lipid profile with that of non-supplemented YSC medium. These results provide further insight into the proposed mechanisms for iron regulation in yeasts especially as these productions strains contain a mutant allele of the iron regulator, mga2. The work presented here also suggests a non-genetic method for control of the lipid profile in Y. lipolytica for use in diverse applications. KEY POINTS: • Iron supplementation increases cell density and lipid titer in Yarrowia lipolytica. • Iron addition reversibly alters lipid portfolio increasing linolenic acid. • Removal of iron from YPD media provides a link to enhanced oleochemical production.

3D Fractional Limb Volume Identifies Reduced Subcutaneous and Lean Mass in Fetal Growth Restriction.

OBJECTIVES: Fetal 2D and 3D fractional limb volume (FLV) measurements by ultrasound can detect fetal lean and subcutaneous mass and possibly percent body fat. Our objectives were to 1) compare FLV measurements in fetuses with fetal growth restriction (FGR) versus small for gestational age (SGA) defined by the International Society of Ultrasound in Obstetrics and Gynecology (ISUOG)-supported international Delphi consensus and 2) correlate FLV findings with birth metrics. We hypothesize that FLV measurements will be significantly smaller in FGR versus SGA fetuses and will correlate closer with Ponderal index (PIx) in the neonate than abdominal circumference (AC). METHODS: Patients were categorized as FGR or SGA as defined by ISUOG. Total thigh volume (TTV), volumes of lean mass (LMV), and fat mass volume (FMV) were calculated from 3D acquisitions. Measurements were compared between groups and correlated with birthweight (BW) and PIx (BW/crown-heal length). RESULTS: The FGR group (n = 37) delivered earlier (37/2 versus 38/0; P = .0847), were lighter (2.2 kg versus 2.6 kg; P = .0003) and had lower PIx (0.023 versus 0.025; P = .0013) than SGAs (n = 22). FGRs had reduced TTV (40.6 versus 48.4 cm3 ; P = .0164), FMV (20.8 versus 25.3 cm3 ; P = .0413), and LMV (19.8 versus 23.1 cm3 ; P = .0387). AC had the highest area under the curve (0.69) for FGR. FMV was more strongly associated with PIx than the AC (P = .0032). CONCLUSIONS: The AC and FLV measurements were significantly reduced in FGR fetuses compared to SGAs. While the AC outperformed FLV in predicting FGR, the FLV correlated best with PIx, which holds investigative promise.

Accidental ingestions to known allergens by food allergic children and adolescents.

BACKGROUND: Accidental ingestions (AI) of food allergens in children compared with adolescents with food allergies are poorly characterized. It is suggested that AIs are higher in adolescents than children and that their reactions may be more severe, presumptively due, at least in part, to increased risk-taking behavior. We compared reported AIs in children versus adolescents. METHODS: An online cross-sectional survey was distributed to parents of children with food allergies via Twitter, food allergy advocacy groups in the UK, South Africa, and Australia, and locally at Children's Hospital Colorado. RESULTS: Of 558 respondents, 105 were parents of adolescents, and 453 had children <12 years. 73% (341) reported an AI since diagnosis, with 85% of adolescents having had an AI versus 70% of children (p = 0.0058). The annualized rate of AI was significantly lower in the adolescent population at 0.21 versus 0.53 in children (p = <0.0001). Although adolescents reported fewer severe reactions (2% vs. 16%, p = 0.0283), more adolescents required epinephrine administered by a medical professional for their most severe AI, (48% vs. 24%, p = 0.0378). Comparison of the two age groups is limited by the fact that many AIs in the adolescent group occurred prior to age 12. There was no significant difference between the groups as to where the food was consumed or the type of food. There was a significant difference in accidental ingestions in patients in all age groups with more than one reported food allergy; 78% of those with more than one food allergy reported a prior history of at least one accidental ingestion, compared with 59% in those with a single food allergy (p < 0.0001). Regional differences were also noted with respondents in the United States reporting 0.3 accidental ingestions a year, 0.4 in the UK, and 0.5 in other countries (p = 0.0455). The number of reactions was, on average, 27% lower (95% CI: 40, 11%) in the United States compared with the UK (p = 0.0019). CONCLUSION: The number of severe reactions, and epinephrine need, differs in children compared with adolescents, although many of the reported reactions in both groups occurred before the age of 12. There were also regional differences with the United States reporting a lower number of AIs and less AIs per year than the other participating regions, as well as increased rates of AI in participants with more than one food allergy. Further characterization of the differences in AIs between children and adolescents, as well as between regions, is needed to assist with more patient-centered anticipatory guidance.

Association between vitamin K1 intake and mortality in the Danish Diet, Cancer, and Health cohort.

Reported associations between vitamin K1 and both all-cause and cause-specific mortality are conflicting. The 56,048 participants from the Danish Diet, Cancer, and Health prospective cohort study, with a median [IQR] age of 56 [52-60] years at entry and of whom 47.6% male, were followed for 23 years, with 14,083 reported deaths. Of these, 5015 deaths were CVD-related, and 6342 deaths were cancer-related. Intake of vitamin K1 (phylloquinone) was estimated from a food-frequency questionnaire (FFQ), and its relationship with mortality outcomes was investigated using Cox proportional hazards models. A moderate to high (87-192 µg/d) intake of vitamin K1 was associated with a lower risk of all-cause [HR (95%CI) for quintile 5 vs quintile 1: 0.76 (0.72, 0.79)], cardiovascular disease (CVD)-related [quintile 5 vs quintile 1: 0.72 (0.66, 0.79)], and cancer-related mortality [quintile 5 vs quintile 1: 0.80 (0.75, 0.86)], after adjusting for demographic and lifestyle confounders. The association between vitamin K1 intake and cardiovascular disease-related mortality was present in all subpopulations (categorised according to sex, smoking status, diabetes status, and hypertension status), while the association with cancer-related mortality was only present in current/former smokers (p for interaction = 0.002). These findings suggest that promoting adequate intakes of foods rich in vitamin K1 may help to reduce all-cause, CVD-related, and cancer-related mortality at the population level.

Rewiring Yarrowia lipolytica toward triacetic acid lactone for materials generation.

Polyketides represent an extremely diverse class of secondary metabolites often explored for their bioactive traits. These molecules are also attractive building blocks for chemical catalysis and polymerization. However, the use of polyketides in larger scale chemistry applications is stymied by limited titers and yields from both microbial and chemical production. Here, we demonstrate that an oleaginous organism (specifically, Yarrowia lipolytica) can overcome such production limitations owing to a natural propensity for high flux through acetyl-CoA. By exploring three distinct metabolic engineering strategies for acetyl-CoA precursor formation, we demonstrate that a previously uncharacterized pyruvate bypass pathway supports increased production of the polyketide triacetic acid lactone (TAL). Ultimately, we establish a strain capable of producing over 35% of the theoretical conversion yield to TAL in an unoptimized tube culture. This strain also obtained an averaged maximum titer of 35.9 ± 3.9 g/L with an achieved maximum specific productivity of 0.21 ± 0.03 g/L/h in bioreactor fermentation. Additionally, we illustrate that a ß-oxidation-related overexpression (PEX10) can support high TAL production and is capable of achieving over 43% of the theoretical conversion yield under nitrogen starvation in a test tube. Next, through use of this bioproduct, we demonstrate the utility of polyketides like TAL to modify commodity materials such as poly(epichlorohydrin), resulting in an increased molecular weight and shift in glass transition temperature. Collectively, these findings establish an engineering strategy enabling unprecedented production from a type III polyketide synthase as well as establish a route through O-functionalization for converting polyketides into new materials.

Placental fatty acid transport across late gestation in a baboon model of intrauterine growth restriction.

KEY POINTS: Intrauterine growth restriction (IUGR) is associated with perinatal morbidity and increased risk of lifelong disease, including neurodevelopmental impairment. Fatty acids (FA) are critical for normal brain development, although their transport across the placenta in IUGR pregnancies is poorly understood. The present study used a baboon model of IUGR (maternal nutrient restriction, MNR) to investigate placental expression of FA transport and binding proteins, and to determine gestational age-related changes in maternal and fetal plasma FA concentrations. We found MNR to be associated with increased placental expression of FA binding and transport proteins in late gestation, with fetal plasma FA concentrations that were similar to those of control animals. The present study is the first to report a profile of fetal and maternal plasma FA concentrations in a baboon model of growth restriction with data that suggest adaptation of placental transport to maintain delivery of critically needed FA. ABSTRACT: Intrauterine growth restriction (IUGR) is associated with specific changes in placental transport of amino acids, folate and ions. However, little is known about placental fatty acid (FA) transport in IUGR. We hypothesized that placental FA transport proteins (FATP) and FA binding proteins (FABP) are up-regulated and fetal plasma FA concentrations are decreased at term in a baboon model of IUGR. Pregnant baboons were fed control or maternal nutrient restricted (MNR) diet (70% of control calories) from gestation day (GD) 30 (term 184 days). Plasma and placental samples were collected at GD120 (control n = 8, MNR n = 9), GD140 (control n = 6, MNR n = 7) and GD170 (control n = 6, MNR n = 6). Placentas were homogenized, and syncytiotrophoblast microvillous plasma membrane (MVM) and basal plasma membranes (BM) were isolated. Protein expression of FABP1, 3, 4 and 5 (homogenate) and FATP2, 4, and 6 (MVM, BM) was determined by Western blotting. FA content in maternal and umbilical vein plasma was measured by gas chromatography-mass spectrometry. Placental FABP1 and FABP5 expression was increased in MNR compared to controls at GD170, as was MVM FATP2 and FATP6 expression at GD140 and FATP2 expression at GD170. BM FATP4 and FATP6 expression was increased in MNR at GD140. Fetal plasma FA concentrations were similar in controls and MNR. These data suggest the adaptation of placental transport when aiming to maintain delivery of critically needed FAs for fetal growth and brain development.

Engineering 4-coumaroyl-CoA derived polyketide production in Yarrowia lipolytica through a ß-oxidation mediated strategy.

Polyketides are a diverse class of molecules sought after for their valuable properties, including as potential pharmaceuticals. Previously, we demonstrated that the oleaginous yeast Yarrowia lipolytica is an optimal host for production of the simple polyketide, triacetic acid lactone (TAL). We here expand the capacities of this host by overcoming previous media challenges and enabling production of more complex polyketides. Specifically, we employ a ß-oxidation related strategy to improve polyketide production directly from defined media. Beyond TAL production, we establish biosynthesis of the 4-coumaroyl-CoA derived polyketides: naringenin, resveratrol, and bisdemethoxycurcumin, as well as the diketide intermediate, (E)-5-(4-hydroxyphenyl)-3-oxopent-4-enoic acid. In this background, we enable high-level de novo production of naringenin through import of both a heterologous pathway and a mutant Y. lipolytica allele. In doing so, we generated an averaged maximum titer of 898 mg/L naringenin, the highest titer reported to date in any host. These results demonstrate that Y. lipolytica is an ideal polyketide production host for more complex 4-coumaroyl-CoA derived products.

Cosmetic outcomes and quality of life in children with cardiac implantable electronic devices.

BACKGROUND: Axillary implant location is an alternative implant location in patients for cardiac implantable electronic devices (CIEDs) for the purposes of improved cosmetic outcome. The impact from the patient's perspective is unknown. The purpose of this study was to compare scar perception scores and quality of life (QOL) in pediatric patients with axillary CIED implant location versus the standard infraclavicular approach. METHODS: This is a multicenter prospective study conducted at eight pediatric centers and it includes patients aged from 8 to 18 years with a CIED. Patients with prior sternotomy were excluded. Scar perception and QOL outcomes were compared between the infraclavicular and axillary implant locations. RESULTS: A total of 141 patients (83 implantable cardioverter defibrillator [ICD]/58 pacemakers) were included, 55 with an axillary device and 86 with an infraclavicular device. Patients with an ICD in the axillary position had better perception of scar appearance and consciousness. Patients in the axillary group reported, on average, a total Pediatric QOL Inventory score that was 6 (1, 11) units higher than the infraclavicular group, after adjusting for sex and race (P = 0.02). CONCLUSIONS: QOL is significantly improved in axillary in comparison to the infraclavicular CIED position, regardless of device type. Scar perception is improved in patients with ICD in the axillary position.

Anterior Cruciate Ligament Injury at the Time of Anterior Tibial Spine Fracture in Young Patients: An Observational Cohort Study.

BACKGROUND: Anterior tibial spine fractures (ATSF) in the skeletally immature parallel anterior cruciate ligament (ACL) tears in adult patients, yet these injuries are generally regarded as mutually exclusive. Biomechanical analysis suggests that intrinsic ACL damage occurs during ATSF, and long-term clinical studies demonstrate residual anteroposterior knee laxity following ATSF. We aim to describe prevalence, demographics, and characteristics of pediatric patients who sustained ATSF with concomitant ACL injury. METHODS: We included 129 patients with ATSF over a 16-year period. Age, sex, injury mechanism, ATSF type, magnetic resonance imaging (MRI) evaluation, treatment modality, ACL injury, and concomitant meniscal/chondral injuries were analyzed. Concurrent ACL injury was confirmed either from MRI or intraoperatively. RESULTS: Nineteen percent (n=25) of ATSF patients had concomitant ACL injury, with ACL injury significantly more likely in type II or type III ATSF compared with type I ATSF (P=0.03). Patients with combined ATSF/ACL injury were significantly older (P=0.02) and more likely to be male (P=0.01). Mechanism of ATSF injury was not associated with ACL injury (P=0.83). Preoperative MRI had low sensitivity (0.09) for recognizing ACL injury at the time of ATSF relative to intraoperative assessment. Half of ATSF/ACL-injured patients had additional meniscal or chondral injury, with meniscal repair or debridement required in 37.5% of the type II ATSF/ACL injury. CONCLUSIONS: There are demographic characteristics, such as age (older) and sex (male), associated with a higher risk of concomitant ACL injury at the time of ATSF. Type II and type III ATSF patterns had a higher prevalence of ACL injury. MRI failed to correctly identify ACL injury at the time of ATSF. Concomitant ACL injury at the time of ATSF is highly prevalent in the skeletally immature, occurring in 19.4% of patients with ATSF. LEVEL OF EVIDENCE: Level IV-case series.

Epidemiology of Anterior Tibial Spine Fractures in Young Patients: A Retrospective Cohort Study of 122 Cases.

BACKGROUND: Historically, bicycle accidents were described as the most common mechanism for pediatric anterior tibial spine fractures (ATSFs). There is a paucity of current literature examining the demographic factors associated with these injuries. The purpose of this cohort study was to characterize the epidemiology of ATSFs presenting to a single tertiary referral pediatric hospital. METHODS: A consecutive cohort of 122 pediatric patients with ATSFs between 1996 and 2014 were reviewed. Radiographic variables, classification of fractures (Meyers and McKeever type), age, sex, height, weight, body mass index, and mechanism of injury were retrieved. Categories of mechanism of injury included organized sports (football, soccer, basketball, lacrosse, wrestling, and gymnastics), bicycling, outdoor sports (skiing, skateboarding, and sledding), fall, motor vehicle collision/pedestrian versus motor vehicle, and trampoline. RESULTS: Organized sports-related injuries represented the most common cause of ATSFs (36%). Other common mechanisms of injury included bicycle accidents (25%), outdoor sports (18%), and falls (11%). There was a higher proportion of males (69%) compared with females (31%). Males (mean age, 11.6 y) were significantly older than females (mean age, 9.8 y) (P=0.004). Younger patients (aged 11.5 y and below) were more likely to have displaced fractures (type III), whereas type I and type II were more common in patients above 11.5 years (P=0.02). Patients with fracture type I were significantly taller than patients with fracture type III. No other variables were found to differ significantly according to fracture severity, including sex, weight, and body mass index. CONCLUSIONS: To our knowledge, our study represents both the largest (n=122) and most up-to-date epidemiological ATSF study in pediatric patients. A higher rate of ATSF occurs due to organized sports rather than bicycling or motor vehicle collision. This 18-year data collection represents a change in the paradigm, and is likely multifactorial, including increased participation in youth sports and early sport specialization. LEVEL OF EVIDENCE: Level IV-retrospective, cohort study.

Metabolic engineering in the host Yarrowia lipolytica.

The nonconventional, oleaginous yeast, Yarrowia lipolytica is rapidly emerging as a valuable host for the production of a variety of both lipid and nonlipid chemical products. While the unique genetics of this organism pose some challenges, many new metabolic engineering tools have emerged to facilitate improved genetic manipulation in this host. This review establishes a case for Y. lipolytica as a premier metabolic engineering host based on innate metabolic capacity, emerging synthetic tools, and engineering examples. The metabolism underlying the lipid accumulation phenotype of this yeast as well as high flux through acyl-CoA precursors and the TCA cycle provide a favorable metabolic environment for expression of relevant heterologous pathways. These properties allow Y. lipolytica to be successfully engineered for the production of both native and nonnative lipid, organic acid, sugar and acetyl-CoA derived products. Finally, this host has unique metabolic pathways enabling growth on a wide range of carbon sources, including waste products. The expansion of carbon sources, together with the improvement of tools as highlighted here, have allowed this nonconventional organism to act as a cellular factory for valuable chemicals and fuels.