New insights into aging in LiNiO2 cathodes from high resolution paramagnetic NMR spectroscopy

Bulk degradation processes are examined in the LiNiO2 cathode using high resolution solid-state NMR, combined with magnetometry and X-ray diffraction. Capacity decay is correlated with bulk heterogeneity, whereby multiple structural domains coexist in the charged state, and the Li content and electrochemical activity of these domains is unraveled for the first time.

The psychophysiology of Mastermind: Characterizing response times and blinking in a high-stakes television game show

Television game shows have proven to be a valuable resource for studying human behavior under conditions of high stress and high stakes. However, previous work has focused mostly on choices-ignoring much of the rich visual information that is available on screen. Here, we take a first step to extracting more of this information by investigating the response times and blinking of contestants in the BBC show Mastermind. In Mastermind, contestants answer rapid-fire quiz questions while a camera slowly zooms in on their faces. By labeling contestants' behavior and blinks from 25 episodes, we asked how accuracy, response times, and blinking varied over the course of the game. For accuracy and response times, we tested whether contestants responded more accurately and more slowly after an error-exhibiting the "post-error increase in accuracy" and "post-error slowing" which has been repeatedly observed in the lab. For blinking, we tested whether blink rates varied according to the cognitive demands of the game-decreasing during periods of cognitive load, such as when pondering a response, and increasing at event boundaries in the task, such as the start of a question. In contrast to the lab, evidence for post-error changes in accuracy and response time was weak, with only marginal effects observed. In line with the lab, blinking varied over the course of the game much as we predicted. Overall, our findings demonstrate the potential of extracting dynamic signals from game shows to study the psychophysiology of behavior in the real world.

High fat intake sustains sorbitol intolerance after antibiotic-mediated Clostridia depletion from the gut microbiota

Carbohydrate intolerance, commonly linked to the consumption of lactose, fructose, or sorbitol, affects up to 30% of the population in high-income countries. Although sorbitol intolerance is attributed to malabsorption, the underlying mechanism remains unresolved. Here, we show that a history of antibiotic exposure combined with high fat intake triggered long-lasting sorbitol intolerance in mice by reducing Clostridia abundance, which impaired microbial sorbitol catabolism. The restoration of sorbitol catabolism by inoculation with probiotic Escherichia coli protected mice against sorbitol intolerance but did not restore Clostridia abundance. Inoculation with the butyrate producer Anaerostipes caccae restored a normal Clostridia abundance, which protected mice against sorbitol-induced diarrhea even when the probiotic was cleared. Butyrate restored Clostridia abundance by stimulating epithelial peroxisome proliferator-activated receptor-gamma (PPAR-γ) signaling to restore epithelial hypoxia in the colon. Collectively, these mechanistic insights identify microbial sorbitol catabolism as a potential target for approaches for the diagnosis, treatment, and prevention of sorbitol intolerance.

Achievement of Target Gain Larger than Unity in an Inertial Fusion Experiment

On December 5, 2022, an indirect drive fusion implosion on the National Ignition Facility (NIF) achieved a target gain G_{target} of 1.5. This is the first laboratory demonstration of exceeding "scientific breakeven" (or G_{target}>1) where 2.05 MJ of 351 nm laser light produced 3.1 MJ of total fusion yield, a result which significantly exceeds the Lawson criterion for fusion ignition as reported in a previous NIF implosion [H. Abu-Shawareb et al. (Indirect Drive ICF Collaboration), Phys. Rev. Lett. 129, 075001 (2022)PRLTAO0031-900710.1103/PhysRevLett.129.075001]. This achievement is the culmination of more than five decades of research and gives proof that laboratory fusion, based on fundamental physics principles, is possible. This Letter reports on the target, laser, design, and experimental advancements that led to this result.

Clinical characteristics of infantile hemangiomas with aggressive, persistent, and destructive ulceration

BACKGROUND/OBJECTIVES

Ulceration is a common complication of infantile hemangioma (IH). Severe, persistent ulceration occurs in a minority of patients. This study aims to characterize the clinical features of IH with aggressive ulceration (AU).

METHODS

Multicenter retrospective study of clinical features of IH with AU.

RESULTS

Thirty-five patients with AU were identified and included in the study. The majority of AU occurred in segmental IH (23/35, 65%). Segmental IH with AU were large (≥10 cm2 ; 16/23, 69%, p < .001) with a thin (<3 mm) superficial component (16/23, 69%, p < .001). Localized IH with AU had a thick (>3 mm) superficial component (11/12, 92%, p < .001). All diaper area IH with AU (9/35) were segmental with thin superficial component (100%, p = .02). IH with AU in the head/neck (10/35) were more commonly localized (67%) and mixed (62.5%), while segmental, thick superficial morphology was more common on trunk (9/35) and upper extremities (7/35).

CONCLUSIONS

IH resulting in AU differ in clinical features by anatomic site. Those in the diaper area are nearly always segmental with thin superficial component, whereas other sites tend to be localized, mixed, with thick superficial component. These distinct phenotypes may prove useful in the clinical setting for physicians to identify patterns of IH ulceration with increased risk of aggressive, persistent ulceration.

Measurement of the Positive Muon Anomalous Magnetic Moment to 0.20 ppm

We present a new measurement of the positive muon magnetic anomaly, a_{μ}≡(g_{μ}-2)/2, from the Fermilab Muon g-2 Experiment using data collected in 2019 and 2020. We have analyzed more than 4 times the number of positrons from muon decay than in our previous result from 2018 data. The systematic error is reduced by more than a factor of 2 due to better running conditions, a more stable beam, and improved knowledge of the magnetic field weighted by the muon distribution, ω[over ˜]_{p}^{'}, and of the anomalous precession frequency corrected for beam dynamics effects, ω_{a}. From the ratio ω_{a}/ω[over ˜]_{p}^{'}, together with precisely determined external parameters, we determine a_{μ}=116 592 057(25)×10^{-11} (0.21 ppm). Combining this result with our previous result from the 2018 data, we obtain a_{μ}(FNAL)=116 592 055(24)×10^{-11} (0.20 ppm). The new experimental world average is a_{μ}(exp)=116 592 059(22)×10^{-11} (0.19 ppm), which represents a factor of 2 improvement in precision.

5-ASA can functionally replace Clostridia to prevent a post-antibiotic bloom of Candida albicans by maintaining epithelial hypoxia

Antibiotic prophylaxis sets the stage for an intestinal bloom of Candida albicans , which can progress to invasive candidiasis in patients with hematologic malignancies. Commensal bacteria can reestablish microbiota-mediated colonization resistance after completion of antibiotic therapy, but they cannot engraft during antibiotic prophylaxis. Here we use a mouse model to provide a proof of concept for an alternative approach, which replaces commensal bacteria functionally with drugs to restore colonization resistance against C. albicans . Streptomycin treatment, which depletes Clostridia from the gut microbiota, disrupted colonization resistance against C. albicans and increased epithelial oxygenation in the large intestine. Inoculating mice with a defined community of commensal Clostridia species reestablished colonization resistance and restored epithelial hypoxia. Notably, these functions of commensal Clostridia species could be replaced functionally with the drug 5-aminosalicylic acid (5-ASA), which activates mitochondrial oxygen consumption in the epithelium of the large intestine. When streptomycin-treated mice received 5-ASA, the drug reestablished colonization resistance against C. albicans and restored physiological hypoxia in the epithelium of the large intestine. We conclude that 5-ASA treatment is a non-biotic intervention that restores colonization resistance against C. albicans without requiring the administration of live bacteria.

Catchment sourcing urban pesticide pollution using constructed wetlands in Melbourne, Australia

A survey of 111 urban constructed stormwater wetlands (median watershed area = 86.8 ha) was conducted to identify the major pesticides present and to determine their major catchment sources (residential, industrial, commercial, sporting ovals) and associations with catchment imperviousness. Melbourne, Australia, has separate stormwater and sewerage systems and these wetlands are designed to treat urban stormwater. To maximise the pesticides that could be detected, three types of passive samplers (POCIS, Chemcatcher® SDB-XC and Chemcatcher® C18) were deployed, along with collection of fine sediments. A total of 231 pesticides were screened using these methods. Pesticides that were detected in >5 % of wetlands were checked to determine their registered use in urban areas using an Australian government database (PubCris). Twenty-five pesticides were detected in >5 % of wetlands: 4 pesticides were associated with non-urban land uses (agriculture and forests), another 4 pesticides had no known registered use in urban areas and 17 were associated with urban areas. The pesticides associated with urban areas were the herbicides simazine, diuron, metolachlor, bromacil, propyzamide and paclobutrazol, the fungicides tebuconazole, propiconazole, metalaxyl, trifloxystrobin, iprodione and carbendazim and the insecticides fipronil, bifenthrin, chlorantraniliprole, thiamethoxam and permethrin. Atrazine was also detected in 59 % of wetlands but has not been registered for urban uses in Australia since 2010. It's presence in Melbourne may be due to legacy issues or aerial transportation from rural areas where it's still widely used in crop cultivation. Generally, the major urban catchment source of pesticides is from residential areas (particularly fipronil and simazine), most likely in wood preservatives, paints and from weed or insect control. Many of these widely used pesticides were correlated with increased catchment imperviousness. Some pesticides (bromacil and imidacloprid) were correlated with commercial premises and chlorantraniliprole was correlated with the presence of sporting ovals in the catchment. No pesticides were specifically correlated with industrial areas. The use of passive samplers and fine sediments, in conjunction with detailed land use mapping of stormwater wetland catchments is very effective and efficient in monitoring and sourcing pesticide contamination in urban environments.

A261 SEVERE ACUTE LIVER INJURY SECONDARY TO WILSON’S DISEASE: A CASE REPORT AND REVIEW OF THE LITERATURE

Background

Wilson’s disease is autosomal recessive and rare (prevalence 1/30000-1/50000) caused by mutations in the ATP7B gene involved in copper excretion. Copper deposition drives hepatic injury, along with neuropsychiatric-ophthalmologic, and hematologic symptoms. Leipzig criteria greater than 4 establishes the diagnosis.

Purpose

We report a case of severe liver injury secondary to probable Wilson’s disease.

Method

Literature review of diagnosis, management including emerging therapies was performed using PubMed.

Result(s)

A 29-year-old otherwise healthy male with no family history of liver disease presented with abdominal pain, jaundice, and severe acute liver injury (ALT 1534 U/L ALP 114 U/L bilirubin 113 umol/L) initially misdiagnosed as hepatitis A in community urgent care. He had worsening liver injury (ALT 1809 U/L bilirubin 411 umol/L), with normal INR and no encephalopathy over an additional 3 weeks and was admitted to our tertiary care centre for further work up. History did not reveal viral prodromes, herbals or natural remedies. CBD oil was the only potential exposure, though longstanding use of the same brand argued against this as a cause. Chronic liver disease workup was negative (viral hepatitides, SARS-CoV-2, alpha-1-antitrypsin, acetaminophen level, iron profile, and comprehensive Mitogen autoantibody panel). Patent vasculature on Doppler US. Liver biopsy showed diffuse lobular inflammation, hepatocyte necrosis, 30% parenchymal involvement, primarily lymphocytes with some eosinophils and plasma cells, and no viral inclusions suggesting acute hepatitis with drugs or viral hepatitis as etiologies. The 24-hour urine copper was elevated at 2.19 umol/d (<0.80). Biopsy copper dry weight 60mcg/g (N<50; >250 diagnostic). Normal ceruloplasmin 0.30g/L and serum copper 25.8 umol/L. MRI brain not suggestive of Wilson’s disease, no Kayser-Fleischer rings on Ophthalmology assessment, and no hemolysis. Given a Leipzig score of 3 suggesting possible Wilson’s disease he was started on penicillamine 1500mg daily. Five weeks later he had serologic (ALT 1061 U/L bilirubin 128 umol/L) improvement, yet elevated elastography at 22kPa IQR 5% likely due to inflammation. Given coverage issues, he was switched to compassionate trientine 500mg BID with further improvement (ALT 347 U/L bilirubin 26 umol/L). Sequencing for ATP7B gene mutations are pending (Blueprint Genetics).

Conclusion(s)

Wilson’s disease should be considered in those with hepatic or neuropsychiatric symptoms, transaminases in the 1000s or acute liver failure. Treatment is lifelong with typically good prognosis and is fatal if untreated. Treatment options include chelators D-penicillamine (first line, with side effects including proteinuria and worsened neurological symptoms) and trientine (fewer side effects). Zinc prevents copper absorption and can be used in asymptomatic patients. Transplant in acute liver failure and end-stage liver disease is guided by the King’s score. Several novel therapies including gene therapy are in development.

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Disclosure of Interest

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Computed Analysis of Retinal Vascular Growth After Bevacizumab Treatment of Retinopathy of Prematurity Until Age 3 Years

PURPOSE

Premature infants, after anti-vascular endothelial growth factor injections for retinopathy of prematurity, have persistent peripheral avascular retina (PAR). PAR is ablated with laser; however, physiologic growth of the retinal vasculature in the long term has not been measured. The purposes of this study were to measure retinal vessel growth after treatment with intravitreal bevacizumab (IVB) for retinopathy of prematurity, using serial fluorescein angiography (FA), until age 3 years, and to assess the timing for providing laser ablation in PAR.

METHODS

Data from an observational, longitudinal clinical study were collected. Angiographic images of eyes treated with IVB were included; imaging data from laser photocoagulation were excluded. All eyes underwent initial examination under general anesthesia with FA and photographic imaging. The retinal vessel length was measured from the temporal margin of the optic disc passing through the foveal center, and the lengths at subsequent FA were compared. To compare the changes in retinal vessel length over time in individual eyes, a paired-sample t test was performed.

FINDINGS

FA images from 70 eyes (35 infants) treated with IVB were available. A total of 150 FA images were available for review; data from 125 images of good quality were used for analysis. The mean postmenstrual ages (PMAs) at first, second, third, and fourth FA were 66.2, 100.9, 135.1, and 180.7 weeks, respectively. The mean retinal vessel length was 14.177 mm at first FA and 13.199 mm at fourth FA (PMA range, 42...234 weeks). Retinal vascular lengths of individual eyes compared over time showed no statistically significant growth from the first FA to age 3 years. The changes in retinal vessel length from first to second FA were -0.117 ± 0.79 mm (p = 0.42; n = 30); from first to third FA, +0.060 ± 0.85 mm (p = 0.79; n = 15); and first to fourth FA, -0.404 ± 1.32 mm (p = 0.45; n = 7).

IMPLICATIONS

Beyond 65 weeks' PMA, no meaningful retinal vascular growth occurred after IVB up to age 3 years, guiding the timing for physicians if laser photocoagulation is being considered. Future studies are needed to address retinal growth changes in the growing eyes of infants.

Relationship of grey matter and white matter changes the visibility of perivascular space across normative lifespan

Background: Perivascular space (PVS), also known as Virchow-Robin space, has been recently recognized as one of the most important components in the glymphatic system of the brain,1 which is closely related to waste and toxins clearance in the brain. On T1- and T2-weighted images, PVS has similar signal intensities to cerebrospinal fluid (CSF), which are frequently observed in the centrum semiovale (CSO) and basal ganglia (BG) regions. A previous study2 has shown that PVS increases with age and enlarged PVS was deemed associated with neurodegenerative and vascular abnormalities in the elderly.3 Although the exact mechanism is still elusive, more evidence showed visible PVS in younger adults or even at the adolescent stage. In this study, we use the human connectome project (HCP) lifespan pilot cohort to characterize the relationship of neuronal tissue to PVS visibility across the normative lifespan. Methods: T1-weighted (0.8mm isotropic, TE/TR=2.12/2400 ms), T2-weighted (0.8mm isotropic, TE/TR=563/3200 ms), and diffusion magnetic resonance imaging (MRI) (1.5 mm isotropic, dir80) data were used from HCP lifespan pilot project (N=27, F/M: 12/15, age 8-75 years). PVS segmentation in white matter (WM) and BG was performed using the same method described in Sepehrband et al.4 (Figure 1). WM PVS volume fraction was calculated by dividing the total PVS volume by WM volume. Pearson correlation and one-way ANOVA were used for statistical analysis. Results: The grey matter (GM) volume fraction is negatively correlated with WM PVS volume (p<0.001, R2=0.374). In addition, we have observed an increase in PVS volume fraction in WM across the lifespan, but there is no significant difference in PVS volume fraction before the age of 55. From an age group range of 8-35 years old, the visible PVS is mostly located in CSO, less PVS is observed in the BG region. However, on the other hand, in the elderly group (age >65 years), high-visibility of PVS is observed both in WM and BG regions. Conclusions: Across the normative lifespan, PVS appearance is negatively correlated with the GM atrophy index, indicating the potential usage of PVS as a marker of neurodegeneration. In WM, we reported that increased PVS is associated with advancing age, which is consistent with previous reports.2 Interestingly, we found that in adolescent populations, the PVS occurs mostly in CSO but not in the BG region. In CSO, as shown from fiber orientation distribution analysis, the PVS is mainly located in crossing fiber regions with lower fiber density. However, In BG regions, the PVS occurs in deep GM nuclei (caudate, putamen) and major fiber tracts such as internal capsules or cortical spinal tracts, which are more densely packed compared to crossing-fibers in CSO. Previous studies have reported that the WM blood flow is inversely correlated with FA,5 the tightly structured fibers tend to show lower blood flow if compared to loosened ones. The high visibility of PVS in CSO may also be due to more loosened fiber structures, which lead to more axonal spaces for PVS fluid movement.

Robust deep learning-based protein sequence design using ProteinMPNN

Although deep learning has revolutionized protein structure prediction, almost all experimentally characterized de novo protein designs have been generated using physically based approaches such as Rosetta. Here, we describe a deep learning-based protein sequence design method, ProteinMPNN, that has outstanding performance in both in silico and experimental tests. On native protein backbones, ProteinMPNN has a sequence recovery of 52.4% compared with 32.9% for Rosetta. The amino acid sequence at different positions can be coupled between single or multiple chains, enabling application to a wide range of current protein design challenges. We demonstrate the broad utility and high accuracy of ProteinMPNN using x-ray crystallography, cryo-electron microscopy, and functional studies by rescuing previously failed designs, which were made using Rosetta or AlphaFold, of protein monomers, cyclic homo-oligomers, tetrahedral nanoparticles, and target-binding proteins.

Hallucinating symmetric protein assemblies

Deep learning generative approaches provide an opportunity to broadly explore protein structure space beyond the sequences and structures of natural proteins. Here we use deep network hallucination to generate a wide range of symmetric protein homo-oligomers given only a specification of the number of protomers and the protomer length. Crystal structures of 7 designs are very close to the computational models (median RMSD: 0.6 Å), as are 3 cryoEM structures of giant 10 nanometer rings with up to 1550 residues and C33 symmetry; all differ considerably from previously solved structures. Our results highlight the rich diversity of new protein structures that can be generated using deep learning, and pave the way for the design of increasingly complex components for nanomachines and biomaterials.

Lawson Criterion for Ignition Exceeded in an Inertial Fusion Experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion.

Abstract 3518: AB248 is a CD8+ T cell selective IL-2 designed for superior safety and anti-tumor efficacy

High dose IL-2 was the first modern immunotherapy to show complete responses in a subset of cancer patients. The liabilities of IL-2 prompted development of second-generation molecules, which signal through the IL-2Rβγ (“not-α” IL-2 and IL-15 variants). Although these molecules avoid vascular leak syndrome, their clinical efficacy appears to be suboptimal compared to high dose IL-2 [1]. Furthermore, not-α IL-2s show biased expansion of NK cells over CD8+ T cells in patients due to their high expression of IL-2Rβ on NK cells, which can act as a sink and contribute to toxicity, and these molecules do not eliminate IL-2Rβγ-mediated activation of Tregs [2, 3]. To maximize the therapeutic potential of IL-2, we developed AB248, a cis-targeted IL-2 fusion protein that selectively signals on CD8+ T-cells with limited activity on the highly IL-2/IL-15-sensitive NK cells and immunosuppressive Tregs. We have previously shown that selective expansion of CD8+ T cells over NK cells and Tregs is achieved in vivo using muAB248, AB248’s murine surrogate. Furthermore, a single dose of muAB248 elicits strong efficacy in multiple tumor models without body weight loss. Here, we detail the properties of AB248, a fusion of a human CD8-targeting antibody that selectively binds to CD8+ T cells over NK cells, and an IL-2 mutein with reduced affinity to IL-2Rα and IL-2Rβ. In STAT5 assays, AB248 showed approximately 1000-fold preference for the activation of CD8+ T cells over NK cells and Tregs. AB248 mediated a dose-dependent selective expansion of CD8 T cells over NK and Tregs in non-human primates. Furthermore, AB248 reproduced the expected in vitro gene signatures of an IL2Rβγ agonist, demonstrating that AB248 recapitulates native IL-2Rβγ signaling selectively on CD8+ T cells.We previously demonstrated in mice that while the efficacy of not-α IL-2 was mediated by CD8+ T cells and not NK cells, toxicity as measured by body weight loss was dependent upon NK cells but not CD8+ T cells. Here, we show that human NK cells may also drive IL-2βγ agonist-induced toxicities. Both IL-2 and not-α IL-2 induced IFN-γ secretion from human PBMCs, whereas AB248 did not. Strikingly, depletion of CD56+ NK cells eliminated IL-2-induced cytokine secretion, demonstrating that human NK cells are capable of spontaneously secreting IFN-γ in response to IL-2 signaling. In the context of TCR stimulation, AB248 induced robust secretion of effector cytokines from CD8+ T cells, but no cytokine secretion was seen in absence of TCR activation. Our data suggest that while AB248 can induce antigen-independent expansion of CD8+ T cells, it only induces effector cytokine secretion in the context of an additional activating signal via the TCR. Collectively, these data show that AB248 demonstrates an improved safety and efficacy profile as compared to not-α IL-2 and is a promising immuno-oncology therapeutic. Ref: 1. Overwijk, Ann. Rev. Med., 2020; 2. Janku, AACR, 2021; 3. Italiano, JCO, 2021

Citation Format: Kelly D. Moynihan, Danielle Pappas, Terrence Park, Wei Chen, Irene Ni, Paul Bessette, Henry Nguyen, David Liu, Mike Chin, Ruth Lan, Aaron Arvey, Ton N. Schumacher, Yik Andy Yeung, Ivana Djuretic. AB248 is a CD8+ T cell selective IL-2 designed for superior safety and anti-tumor efficacy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3518.

Abstract 2882: Selective activation of CD8+ T cells by a CD8-targeted IL-21 results in enhanced anti-tumor efficacy and safety

Interleukin-21 (IL-21) is a pleiotropic cytokine that activates multiple lymphoid and myeloid immune cell subsets. IL-21 can have beneficial effects on anti-tumor immune responses due to its ability to activate STAT3 in CD8+ T cells and promote cytotoxicity, memory cell differentiation and survival. However, IL-21 can also induce immunosuppressive effects, such as suppression of antigen presentation, which may directly oppose its anti-tumor effects on CD8+ T cells. Although recombinant IL-21 did show monotherapy activity in the clinic, overall response rates were modest. In addition to the pharmacological sink created by the broad expression of IL-21R and potential immunosuppressive effects, clinical utility of IL-21 was further limited by its low bioavailability and dose-limiting toxicities. We hypothesized that maximizing IL-21’s activity on CD8+ T cells while avoiding non-CD8 cells would enhance efficacy and improve tolerability. We developed cis-targeted IL-21 (CD8-IL21) fusion proteins that exhibit improved bioavailability and selectively activate CD8+ T cells while exhibiting minimal activity on non-CD8 cells. In vitro phospho-STAT3 assays with CD8-IL21 in mouse splenocytes and human peripheral blood cells showed &gt;1000-fold selective activation of CD8+ T cells over non-CD8 cells. A mouse CD8-IL21 surrogate demonstrated profound single agent efficacy in multiple syngeneic tumor models at considerably lower doses than an untargeted IL-21 control, despite similar in vitro potency. CD8-IL21 mediated anti-tumor efficacy without inducing body weight loss. Whereas prior data showed that repeated high doses of tumor-targeted IL-21 fusion protein (&gt;3 mg/kg) had single agent efficacy in the MC38 tumor model overexpressing a tumor antigen [1], here we show that a single dose of CD8-targeted IL-21 as low as 0.1 mg/kg induced curative responses in mice bearing established MC38 tumors. We demonstrated using the lymphocyte migration inhibitor FTY720 that this enhanced potency of low dose CD8-IL21 is predominately driven by the activation of peripheral CD8 T cells. Furthermore, curative effects in the MC38 model were elicited in the absence of substantial CD8+ T cell expansion (&lt;1.5-fold) suggesting that CD8-IL21 mediated anti-tumor efficacy through modulation of T cell phenotype. A CD8-IL21 selective for human and cynomolgus CD8+ T cells with improved bioavailability also exhibited improved tolerability over untargeted IL-21 in cynomolgus monkeys, showing that there is a tolerability benefit to CD8-selective activation. In summary, CD8-IL21 showed improved efficacy and safety over untargeted IL-21, demonstrating clear promise as a novel therapeutic agent which by activating STAT3 signaling in CD8+ T cells may offer complementary benefits to activation of STAT5 signaling by cytokines such as IL-2 and IL-15.Ref: 1. Deng et al., 2020

Citation Format: Renee Greer, David Liu, Henry Nguyen, Ruth Lan, Wei Wei Prior, Meghana Sukthankar, Paul Mesko, irene Ni, Mike Chin, Kelly Moynihan, Ton Schumacher, Ivana Djuretic, Andy Yeung. Selective activation of CD8+ T cells by a CD8-targeted IL-21 results in enhanced anti-tumor efficacy and safety [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2882.

Host cells subdivide nutrient niches into discrete biogeographical microhabitats for gut microbes

Changes in the microbiota composition are associated with many human diseases, but factors that govern strain abundance remain poorly defined. We show that a commensal Escherichia coli strain and a pathogenic Salmonella enterica serovar Typhimurium isolate both utilize nitrate for intestinal growth, but each accesses this resource in a distinct biogeographical niche. Commensal E. coli utilizes epithelial-derived nitrate, whereas nitrate in the niche occupied by S. Typhimurium is derived from phagocytic infiltrates. Surprisingly, avirulent S. Typhimurium was shown to be unable to utilize epithelial-derived nitrate because its chemotaxis receptors McpB and McpC exclude the pathogen from the niche occupied by E. coli. In contrast, E. coli invades the niche constructed by S. Typhimurium virulence factors and confers colonization resistance by competing for nitrate. Thus, nutrient niches are not defined solely by critical resources, but they can be further subdivided biogeographically within the host into distinct microhabitats, thereby generating new niche opportunities for distinct bacterial species.

Trapped Alkali-Metal Rydberg Qubit

Rydberg interactions of trapped alkali-metal atoms are used widely to facilitate quantum gate operations in quantum processors and repeaters. In most laboratory realizations using this protocol, the Rydberg states are repelled by the trapping laser fields, requiring that the fields be turned off during gate operations. Here we create a quasi-two-level system in a regime of Rydberg excitation blockade for a mesoscopic Rb ensemble of several hundred atoms confined in a magic-wavelength optical lattice. We observe many-body Rabi oscillations between the ground and collective Rydberg state. In addition we use Ramsey interference techniques to obtain the light shifts of both the lower and upper states of the collective qubit. Whereas the coupling producing the Rabi oscillations is enhanced by a factor of sqrt[N], there is no corresponding enhancement for the light shifts. We derive an effective two-level model which is in good agreement with our observations. Trapped Rydberg qubits and an effective two-level description are expected to have broad applicability for studies of quantum simulation and networking using collective encoding in ensembles of neutral atoms.

Regulation of Brain Primary Cilia Length by MCH Signaling: Evidence from Pharmacological, Genetic, Optogenetic, and Chemogenic Manipulations

The melanin-concentrating hormone (MCH) system is involved in numerous functions, including energy homeostasis, food intake, sleep, stress, mood, aggression, reward, maternal behavior, social behavior, and cognition. In rodents, MCH acts on MCHR1, a G protein-coupled receptor, which is widely expressed in the brain and abundantly localized to neuronal primary cilia. Cilia act as cells' antennas and play crucial roles in cell signaling to detect and transduce external stimuli to regulate cell differentiation and migration. Cilia are highly dynamic in terms of their length and morphology; however, it is not known if cilia length is causally regulated by MCH system activation in vivo. In the current work, we examined the effects of activation and inactivation of MCH system on cilia lengths by using different experimental models and methodologies, including organotypic brain slice cultures from rat prefrontal cortex (PFC) and caudate-putamen (CPu), in vivo pharmacological (MCHR1 agonist and antagonist GW803430), germline and conditional genetic deletion of MCHR1 and MCH, optogenetic, and chemogenetic (designer receptors exclusively activated by designer drugs (DREADD)) approaches. We found that stimulation of MCH system either directly through MCHR1 activation or indirectly through optogenetic and chemogenetic-mediated excitation of MCH-neuron, caused cilia shortening, detected by the quantification of the presence of ADCY3 protein, a known primary cilia marker. In contrast, inactivation of MCH signaling through pharmacological MCHR1 blockade or through genetic manipulations - germline deletion of MCHR1 and conditional ablation of MCH neurons - induced cilia lengthening. Our study is the first to uncover the causal effects of the MCH system in the regulation of the length of brain neuronal primary cilia. These findings place MCH system at a unique position in the ciliary signaling in physiological and pathological conditions and implicate MCHR1 present at primary cilia as a potential therapeutic target for the treatment of pathological conditions characterized by impaired primary cilia function associated with the modification of its length.

Hidradenitis Suppurativa in the Pediatric Population: An International, Multicenter, Retrospective, Cross-sectional Study of 481 Pediatric Patients

Importance

Hidradenitis suppurativa (HS) in pediatric patients has been understudied. Increased awareness and recognition of HS prevalence in children demand efforts to better understand this condition.

Objective

To describe the demographics, clinical features, treatment, associated comorbidities, and outcomes in a large cohort of pediatric patients with HS.

Design, Setting, and Participants

International, multicenter, retrospective medical record review of pediatric patients (aged 1-18 years) with a clinical diagnosis of HS carried out in 10 dermatology clinics across the US, Canada, Israel, Australia, and Italy from January 1996 to January 2017.

Main Outcomes and Measures

Patient demographics, clinical features, severity, associated comorbidities, and treatments in pediatric patients with HS.

Results

This cross-sectional study included 481 patients diagnosed with HS. Overall, 386 (80%) were girls. The mean (SD) age of disease onset was 12.5 (2.9) years, and the mean (SD) age at diagnosis was 14.4 (3.5) years. Family history of HS was present in 111 of 271 (41%) patients. First signs/symptoms reported at disease onset were cyst/abscess in 229 of 481 (48%), pain/tenderness in 118 of 481 (25%), and papules/pustules in 117 of 481 (24%). At initial dermatologic assessment, 233 of 481 (48%) patients already had evidence of skin scarring. Disease severity (Hurley staging) was documented in 288 of 481 (60%) patients (47% stage 1, 45% stage 2 and 8% stage 3). Comorbid conditions were reported in 406 of 481 (85%) patients, the most common being obesity (263/406 [65%]) and acne vulgaris (118/406 [29%]). Complications occurred in 378 of 481 (79%) patients, the most common of which were scars or contractures (301/378 [80%]).

Conclusions and Relevance

The findings of this study indicate that there is a gap in recognizing and diagnosing pediatric HS. Pediatric patients with HS are likely to present with other comorbidities. Prospective observational and interventional studies are needed to better understand clinical course and optimal treatments for pediatric HS.

Clinical Features, Prognostic Factors, and Treatment Interventions for Ulceration in Patients With Infantile Hemangioma

Importance

Ulceration is a common complication of infantile hemangioma (IH), which leads to substantial morbidity. Ulceration in IH has not been systematically studied since the advent of β-blocker therapy for IH.

Objectives

To examine treatment interventions used for ulceration in IH and identify clinical prognostic indicators of healing time.

Design, Setting, and Participants

A retrospective, multicenter cohort study was conducted on 436 consecutive patients with a clinical diagnosis of ulcerated IH and available clinical photographs. Patients receiving care at tertiary referral centers evaluated between 2012 and 2016 were included; statistical and data analysis were performed from February 7 to April 27, 2020.

Exposures

Clinical characteristics, treatment interventions, course, complications, and resource use were analyzed. Treatment interventions for ulceration in IH included local (wound care, topical), systemic (β-blocker, corticosteroids), and procedural (pulsed-dye laser).

Main Outcomes and Measures

The primary end point was time to complete or nearly complete ulceration healing. Clinical characteristics were analyzed to determine the responses to most common interventions and prognostic factors for healing of ulceration.

Results

Of the 436 patients included in the study, 327 were girls (75.0%); median age at ulceration was 13.7 weeks (interquartile range, 8.86-21.30 weeks). The median heal time was 4.79 weeks (95% CI, 3.71-5.86 weeks) with wound care alone, 5.14 weeks (95% CI, 4.57-6.00 weeks) with timolol, 6.36 weeks (95% CI, 5.57-8.00 weeks) with a systemic β-blocker, and 7.71 weeks (95% CI, 6.71-10.14 weeks) with multimodal therapy. After adjusting for IH size, a dose of propranolol less than or equal to 1 mg/kg/d was associated with shorter healing time compared with higher propranolol doses (hazard ratio, 2.04; 95% CI, 1.11 to 3.73; P = .02). Size of the IH was identified as a significant prognostic factor for healing time in multivariable analysis. Increasing size of IH portends a proportionately longer time to heal of the ulceration.

Conclusions and Relevance

Despite the use of β-blockers, this cohort study found that a subset of patients with IH ulceration continued to experience prolonged IH healing times. Larger IH size appears to be a poor prognostic factor for time to heal. For patients requiring systemic therapy, initiation of propranolol at lower doses (≤1 mg/kg/d) should be considered.

High-fat diet-induced colonocyte dysfunction escalates microbiota-derived trimethylamine N-oxide

A Western-style, high-fat diet promotes cardiovascular disease, in part because it is rich in choline, which is converted to trimethylamine (TMA) by the gut microbiota. However, whether diet-induced changes in intestinal physiology can alter the metabolic capacity of the microbiota remains unknown. Using a mouse model of diet-induced obesity, we show that chronic exposure to a high-fat diet escalates Escherichia coli choline catabolism by altering intestinal epithelial physiology. A high-fat diet impaired the bioenergetics of mitochondria in the colonic epithelium to increase the luminal bioavailability of oxygen and nitrate, thereby intensifying respiration-dependent choline catabolism of E. coli In turn, E. coli choline catabolism increased levels of circulating trimethlamine N-oxide, which is a potentially harmful metabolite generated by gut microbiota.

Limited utility of repeated vital sign monitoring during initiation of oral propranolol for complicated infantile hemangioma

BACKGROUND

Initial propranolol recommendations for infantile hemangioma published in 2013 were intended as provisional best practices to be updated as evidence-based data emerged.

METHODS

A retrospective multicenter study was performed to evaluate utility of prolonged monitoring after first propranolol dose and escalation(s). Inclusion criteria included diagnosis of hemangioma requiring propranolol of greater than or equal to 0.3 mg/kg per dose, younger than 2 years, and heart rate monitoring for greater than or equal to 1 hour. Data collected included demographics, dose, vital signs, and adverse events.

RESULTS

A total of 783 subjects met inclusion criteria; median age at initiation was 112 days. None of the 1148 episodes of prolonged monitoring warranted immediate intervention or drug discontinuation. No symptomatic bradycardia or hypotension occurred during monitoring. Mean heart rate change from baseline to 1 hour was -8.19/min (±15.54/min) and baseline to 2 hours was -9.24/min (±15.84/min). Three preterm subjects had dose adjustments because of prescriber concerns about asymptomatic vital sign changes. No significant difference existed in pretreatment heart rate or in heart rate change between individuals with later adverse events during treatment and those without.

CONCLUSION

Prolonged monitoring for initiation and escalation of oral propranolol rarely changed management and did not predict future adverse events. Few serious adverse events occurred during therapy; none were cardiovascular.

Large-scale analysis reveals spatiotemporal circadian patterns of cilia transcriptomes in the primate brain

Cilia are dynamic subcellular systems, with core structural and functional components operating in a highly coordinated manner. Since many environmental stimuli sensed by cilia are circadian in nature, it is reasonable to speculate that genes encoding cilia structural and functional components follow rhythmic circadian patterns of expression. Using computational methods and the largest spatiotemporal gene expression atlas of primates, we identified and analyzed the circadian rhythmic expression of cilia genes across 22 primate brain areas. We found that around 73% of cilia transcripts exhibited circadian rhythmicity across at least one of 22 brain regions. In 12 brain regions, cilia transcriptomes were significantly enriched with circadian oscillating transcripts, as compared to the rest of the transcriptome. The phase of the cilia circadian transcripts deviated from the phase of the majority of the background circadian transcripts, and transcripts coding for cilia basal body components accounted for the majority of cilia circadian transcripts. In addition, adjacent or functionally connected brain nuclei had large overlapping complements of circadian cilia genes. Most remarkably, cilia circadian transcripts shared across the basal ganglia nuclei and the prefrontal cortex peaked in these structures in sequential fashion that is similar to the sequential order of activation of the basal ganglia-cortical circuitry in connection with movement coordination, albeit on completely different timescales. These findings support a role for the circadian spatiotemporal orchestration of cilia gene expression in the normal physiology of the basal ganglia-cortical circuit and motor control. Studying orchestrated cilia rhythmicity in the basal ganglia-cortical circuits and other brain circuits may help develop better functional models, and shed light on the causal effects cilia functions have on these circuits and on the regulation of movement and other behaviors.

Anaerobic Respiration of NOX1-Derived Hydrogen Peroxide Licenses Bacterial Growth at the Colonic Surface

The colonic microbiota exhibits cross-sectional heterogeneity, but the mechanisms that govern its spatial organization remain incompletely understood. Here we used Citrobacter rodentium, a pathogen that colonizes the colonic surface, to identify microbial traits that license growth and survival in this spatial niche. Previous work showed that during colonic crypt hyperplasia, type III secretion system (T3SS)-mediated intimate epithelial attachment provides C. rodentium with oxygen for aerobic respiration. However, we find that prior to the development of colonic crypt hyperplasia, T3SS-mediated intimate attachment is not required for aerobic respiration but for hydrogen peroxide (H₂O₂) respiration using cytochrome c peroxidase (Ccp). The epithelial NADPH oxidase NOX1 is the primary source of luminal H₂O₂ early after C. rodentium infection and is required for Ccp-dependent growth. Our results suggest that NOX1-derived H₂O₂ is a resource that governs bacterial growth and survival in close proximity to the mucosal surface during gut homeostasis.

Patterns of cilia gene dysregulations in major psychiatric disorders

Primary cilia function as cells' antennas to detect and transduce external stimuli and play crucial roles in cell signaling and communication. The vast majority of cilia genes that are causally linked with ciliopathies are also associated with neurological deficits, such as cognitive impairments. Yet, the roles of cilia dysfunctions in the pathogenesis of psychiatric disorders have not been studied. Our aim is to identify patterns of cilia gene dysregulation in the four major psychiatric disorders: schizophrenia (SCZ), autism spectrum disorder (ASD), bipolar disorder (BP), and major depressive disorder (MDD). For this purpose, we acquired differentially expressed genes (DEGs) from the largest and most recent publicly available databases. We found that 42%, 24%, 17%, and 15% of brain-expressed cilia genes were significantly differentially expressed in SCZ, ASD, BP, and MDD, respectively. Several genes exhibited cross-disorder overlap, suggesting that typical cilia signaling pathways' dysfunctions determine susceptibility to more than one psychiatric disorder or may partially underlie their pathophysiology. Our study revealed that genes encoding proteins of almost all sub-cilia structural and functional compartments were dysregulated in the four psychiatric disorders. Strikingly, the genes of 75% of cilia GPCRs and 50% of the transition zone proteins were differentially expressed in SCZ. The present study is the first to draw associations between cilia and major psychiatric disorders, and is the first step toward understanding the role that cilia components play in their pathophysiological processes, which may lead to novel therapeutic targets for these disorders.

Measurement of the Positive Muon Anomalous Magnetic Moment to 0.46 ppm

We present the first results of the Fermilab National Accelerator Laboratory (FNAL) Muon g-2 Experiment for the positive muon magnetic anomaly a_{μ}≡(g_{μ}-2)/2. The anomaly is determined from the precision measurements of two angular frequencies. Intensity variation of high-energy positrons from muon decays directly encodes the difference frequency ω_{a} between the spin-precession and cyclotron frequencies for polarized muons in a magnetic storage ring. The storage ring magnetic field is measured using nuclear magnetic resonance probes calibrated in terms of the equivalent proton spin precession frequency ω[over ˜]_{p}^{'} in a spherical water sample at 34.7 °C. The ratio ω_{a}/ω[over ˜]_{p}^{'}, together with known fundamental constants, determines a_{μ}(FNAL)=116 592 040(54)×10^{-11} (0.46 ppm). The result is 3.3 standard deviations greater than the standard model prediction and is in excellent agreement with the previous Brookhaven National Laboratory (BNL) E821 measurement. After combination with previous measurements of both μ^{+} and μ^{-}, the new experimental average of a_{μ}(Exp)=116 592 061(41)×10^{-11} (0.35 ppm) increases the tension between experiment and theory to 4.2 standard deviations.

Genomic resources in plant breeding for sustainable agriculture

Climate change during the last 40 years has had a serious impact on agriculture and threatens global food and nutritional security. From over half a million plant species, cereals and legumes are the most important for food and nutritional security. Although systematic plant breeding has a relatively short history, conventional breeding coupled with advances in technology and crop management strategies has increased crop yields by 56 % globally between 1965-85, referred to as the Green Revolution. Nevertheless, increased demand for food, feed, fiber, and fuel necessitates the need to break existing yield barriers in many crop plants. In the first decade of the 21st century we witnessed rapid discovery, transformative technological development and declining costs of genomics technologies. In the second decade, the field turned towards making sense of the vast amount of genomic information and subsequently moved towards accurately predicting gene-to-phenotype associations and tailoring plants for climate resilience and global food security. In this review we focus on genomic resources, genome and germplasm sequencing, sequencing-based trait mapping, and genomics-assisted breeding approaches aimed at developing biotic stress resistant, abiotic stress tolerant and high nutrition varieties in six major cereals (rice, maize, wheat, barley, sorghum and pearl millet), and six major legumes (soybean, groundnut, cowpea, common bean, chickpea and pigeonpea). We further provide a perspective and way forward to use genomic breeding approaches including marker-assisted selection, marker-assisted backcrossing, haplotype based breeding and genomic prediction approaches coupled with machine learning and artificial intelligence, to speed breeding approaches. The overall goal is to accelerate genetic gains and deliver climate resilient and high nutrition crop varieties for sustainable agriculture.

Pediatric maculopapular cutaneous mastocytosis: Retrospective review of signs, symptoms, and associated conditions

BACKGROUND/OBJECTIVES

Though maculopapular cutaneous mastocytosis is the most common form of pediatric mastocytosis, it remains unclear which patients will experience severe symptoms. We sought to better define the presentation and the cutaneous and systemic signs and symptoms in patients with maculopapular cutaneous mastocytosis.

METHODS

We analyzed retrospective data on 227 patients diagnosed with maculopapular cutaneous mastocytosis prior to age 15 years from five US clinical sites. We collected data on signs, symptoms, age of onset, and laboratory testing.

RESULTS

Median age of onset of maculopapular cutaneous mastocytosis was 3 months, with 94% of patients presenting prior to age 2 (range 0-15 years). Patients presenting before age 2 had significantly lower serum tryptase level (P = .019). Greater number of skin lesions (P = .006), number of reported skin signs and symptoms (P < .001), and higher tryptase levels (P < .001) were associated with more systemic symptoms.

CONCLUSION

Children with maculopapular cutaneous mastocytosis, who have greater skin involvement, higher serum tryptase level, and more skin signs and symptoms, are more likely to have systemic symptoms.

Using longitudinally sampled viral nucleotide sequences to characterize the drivers of HIV-1 transmission

OBJECTIVES

Understanding the drivers of HIV-1 transmission is of importance for curbing the ongoing epidemic. Phylogenetic methods based on single viral sequences allow us to assess whether two individuals are part of the same viral outbreak, but cannot on their own assess who potentially transmitted the virus. We developed and assessed a molecular epidemiology method with the main aim to screen cohort studies for and to characterize individuals who are 'potential HIV-1 transmitters', in order to understand the drivers of HIV-1 transmission.

METHODS

We developed and validated a molecular epidemiology approach using longitudinally sampled viral Sanger sequences to characterize potential HIV-1 transmitters in the Swiss HIV Cohort Study.

RESULTS

Our method was able to identify 279 potential HIV-1 transmitters and allowed us to determine the main epidemiological and virological drivers of transmission. We found that the directionality of transmission was consistent with infection times for 72.9% of 85 potential HIV-1 transmissions with accurate infection date estimates. Being a potential HIV-1 transmitter was associated with risk factors including viral load [adjusted odds ratio_{multivariable} (95% confidence interval): 1.86 (1.49-2.32)], syphilis coinfection [1.52 (1.06-2.19)], and recreational drug use [1.45 (1.06-1.98)]. By contrast for the potential HIV-1 recipients, this association was weaker or even absent [1.18 (0.82-1.72), 0.89 (0.52-1.55) and 1.53 (0.98-2.39), respectively], indicating that inferred directionality of transmission is useful at the population level.

CONCLUSIONS

Our results indicate that longitudinally sampled Sanger sequences do not provide sufficient information to identify transmitters with high certainty at the individual level, but that they allow the drivers of transmission at the population level to be characterized.

Validation of a fuel particle dissolution model with samples from the Red Forest within the Chernobyl exclusion zone

The contamination in the near exclusion zone of the Chernobyl nuclear power plant (ChNPP) with ⁹⁰Sr, ^238-240Pu and ²⁴¹Am is associated with irradiated nuclear fuel particles. Fit for purpose models enabling long term prediction of mobility and bioavailability of particle-associated radionuclides are crucial for radiation protection of humans and the environment, as well as for planning of remediation measures and future land use. In the present work, a dynamic fuel particle dissolution model developed in 1999-2002 is described and validated using data based on sampling in 2015. The model is based on the characterization of the radionuclide source term of the waste in a shallow sub-surface radioactive waste storage, trench #22, in the Chernobyl Pilot Site (CPS) located in the Red Forest, 2.5 km west of the ChNPP, as well as the description of physical and chemical properties of the fuel particles and subsequent radionuclide leaching into the soil solution. Transformation rate constants of the fuel particle dissolution model related to topsoil, radioactive waste trench and submerged materials, and drained cooling pond sediments, should largely control the mobility and bioavailability of radionuclides (e.g., solubility in the soil, migration to groundwater and transfer to plants). The predicting power of the Chernobyl fuel particle dissolution model with respect to radionuclide leaching dynamics was validated using samples from the same experimental site, showing that predicted particle leaching and subsequent mobility and bioavailability were within 46 ± 3% of the observed data. Therefore, linking source- and release-scenario dependent characteristics of radioactive particles to their potential weathering can provide information that can be implemented in impact assessments models for existing contaminated areas as well as for future events.

Quality Improvement Project Demonstrate that Prolonged Pre-Analytical Time Does Not Lead to False Negative Blood Cultures

Introduction/Objective

Bacterial infection is a significant cause of morbidity and mortality. Prompt identification of microorganisms and their susceptibilities to antimicrobial therapies is critical in the management of patients with bloodstream infections. Blood cultures are collected in paired aerobic and anaerobic bottles. However, transport delays might allow some organisms to grow extensively prior to incubation in the blood culture instruments, leading to false-negative culture results. The Detroit Medical Center utilizes the BD Bactec™ instruments for blood culture incubation and the Verigene DNA-based molecular assay for the identification of bacteria and major resistance genes. It has a core microbiology lab that serves 6 hospitals, however, 2 of the hospitals are remotely located.

The aim of this project was to determine if transportation delays led to significant false-negative culture results. If significant false negativity occurred, additional Bactec™ instruments would need to be purchased.

Methods

For one month, we tracked the collection of blood cultures to incubation time at one of the remote hospitals. All blood cultures that remain negative after 164 hours of incubation are routinely discarded. However, in this case, they were subcultured to a Petri plate containing chocolate agar for 30 days. Any organisms that grew were identified by standard lab techniques.

Results

Of the 547 negative culture bottles that were subcultured for possible false-negative results, only 3 (0.5%) bottles grew bacteria. All three were isolated from different patients. The mean time from blood collection to incubation in the instrument was 4-8 hours. The isolates either met criteria for contaminated cultures, or they grew the same pathogen that had previously been identified in the paired bottle from the same culture. The organisms isolated include coagulase negative Staphylococcus species, Staphylococcus pettenkoferi, and Pseudomonas aeruginosa. No unexpected pathogenic organisms were detected.

Conclusion

Our results demonstrate that prolonged pre-analytical time does not lead to false-negative blood culture results. The patients’ diagnoses were not changed, therefore, the purchase of additional blood culture instruments was not necessary. However, transportation time from the patient floors to the main microbiology lab needs to be improved to meet the recommended 2 hours pre-analytical time.

Skin-Related complications of Klippel-Trenaunay Syndrome: a retrospective review of 410 patients

BACKGROUND

Little is known about skin-related complications in Klippel-Trenaunay syndrome (KTS), a complex vascular anomaly defined by capillary malformation (CM), venous malformation (VM) ± lymphatic malformation (LM) and limb overgrowth. Reported skin-related complications of KTS include ulceration, vascular ectasias (blebs), bleeding and infection.

OBJECTIVE

To determine the spectrum, prevalence and predictors of skin-related complications in KTS.

METHODS

A retrospective review of 410 patients fulfilling KTS criteria was performed to assess for the presence of skin-related complications.

RESULTS

Skin-related complications were present in 45% of patients. Most prevalent were CM-related complications including blebs, bleeding, thickening (25%), cellulitis (22%) and ulceration (21%). Features positively associated with skin-related complications were presence of LM (OR 17.17; P < 0.001), VM on the buttocks/perineum/genitalia (OR 1.92; P = 0.009), CM on the feet (OR 1.77; P = 0.039) and male sex (OR 1.63; P = 0.034). Features negatively associated with skin-related complications were CM on the trunk (OR 0.59; P = 0.029) and tissue hypertrophy of the hands (OR 0.27; P = 0.025).

CONCLUSION

Skin-related complications affect nearly half of patients with KTS. Those with lymphatic involvement or malformation presence in the undergarment area or feet are most at risk.

Phase Matching in Lower Dimensions

Phase matching refers to a process in which atom-field interactions lead to the creation of an output field that propagates coherently through the interaction volume. By studying light scattering from arrays of cold atoms, we show that conditions for phase matching change as the dimensionality of the system decreases. In particular, for a single atomic chain, there is phase-matched reflective scattering in a cone about the symmetry axis of the array that scales as the square of the number of atoms in the chain. For two chains of atoms, the phase-matched reflective scattering can be enhanced or diminished as a result of Bragg scattering. Such scattering can be used for mapping collective states within an array of neutral atoms onto propagating light fields and for establishing quantum links between separated arrays.