Synthetic development of a broadly neutralizing antibody against snake venom long-chain α-neurotoxins.

Snakebite envenoming is a major global public health concern for which improved therapies are urgently needed. The antigenic diversity present in snake venom toxins from various species presents a considerable challenge to the development of a universal antivenom. Here, we used a synthetic human antibody library to find and develop an antibody that neutralizes long-chain three-finger α-neurotoxins produced by numerous medically relevant snakes. Our antibody bound diverse toxin variants with high affinity, blocked toxin binding to the nicotinic acetylcholine receptor in vitro, and protected mice from lethal venom challenge. Structural analysis of the antibody-toxin complex revealed a binding mode that mimics the receptor-toxin interaction. The overall workflow presented is generalizable for the development of antibodies that target conserved epitopes among antigenically diverse targets, and it offers a promising framework for the creation of a monoclonal antibody-based universal antivenom to treat snakebite envenoming.

The gut-brain axis mediates bacterial driven modulation of reward signaling.

OBJECTIVE: Our goal is to investigate if microbiota composition modulates reward signaling and assess the role of the vagus in mediating microbiota to brain communication. METHODS: Male germ-free Fisher rats were colonized with gastrointestinal contents from chow (low fat (LF) ConvLF) or HF (ConvHF) fed rats. RESULTS: Following colonization, ConvHF rats consumed significantly more food than ConvLF animals. ConvHF rats displayed lower feeding-induced extracellular DOPAC levels (a metabolite of dopamine) in the Nucleus Accumbens (NAc) as well as reduced motivation for HF foods compared to ConvLF rats. Dopamine receptor 2 (DDR2) expression levels in the NAc were also significantly lower in ConvHF animals. Similar deficits were observed in conventionally raised HF fed rats, showing that diet-driven alteration in reward can be initiated via microbiota. Selective gut to brain deafferentation restored DOPAC levels, DRD2 expression, and motivational drive in ConvHF rats. CONCLUSIONS: We concluded from these data that a HF-type microbiota is sufficient to alter appetitive feeding behavior and that bacteria to reward communication is mediated by the vagus nerve.

Fully synthetic platform to rapidly generate tetravalent bispecific nanobody-based immunoglobulins.

Nanobodies bind a target antigen with a kinetic profile similar to a conventional antibody, but exist as a single heavy chain domain that can be readily multimerized to engage antigen via multiple interactions. Presently, most nanobodies are produced by immunizing camelids; however, platforms for animal-free production are growing in popularity. Here, we describe the development of a fully synthetic nanobody library based on an engineered human VH3-23 variable gene and a multispecific antibody-like format designed for biparatopic target engagement. To validate our library, we selected nanobodies against the SARS-CoV-2 receptor-binding domain and employed an on-yeast epitope binning strategy to rapidly map the specificities of the selected nanobodies. We then generated antibody-like molecules by replacing the VH and VL domains of a conventional antibody with two different nanobodies, designed as a molecular clamp to engage the receptor-binding domain biparatopically. The resulting bispecific tetra-nanobody immunoglobulins neutralized diverse SARS-CoV-2 variants with potencies similar to antibodies isolated from convalescent donors. Subsequent biochemical analyses confirmed the accuracy of the on-yeast epitope binning and structures of both individual nanobodies, and a tetra-nanobody immunoglobulin revealed that the intended mode of interaction had been achieved. This overall workflow is applicable to nearly any protein target and provides a blueprint for a modular workflow for the development of multispecific molecules.

Association Between Vancomycin AUC and Clinical Failure in Patients with Streptococcal Bacteremia.

Background: Monitoring of vancomycin using the area under the curve (AUC) to minimum inhibitory concentration (MIC) ratio is now preferred for serious methicillin-resistant Staphylococcus aureus infections. Vancomycin AUC/MIC monitoring is being investigated but is not yet well elucidated with other bacterial pathogens. Methods: A retrospective cross-sectional study was conducted assessing patients with streptococcal bacteremia treated with vancomycin definitive therapy. AUC was calculated using a Bayesian approach, and classification and regression tree analysis was used to identify a vancomycin AUC threshold predictive of clinical failure. Results: Eleven patients had a vancomycin AUC < 329 of which 8 (73%) experienced clinical failure, while 35 patients had a vancomycin AUC ≥ 329 of which 12 (34%) experienced clinical failure (P = .04). Hospital length of stay was longer in the AUC ≥ 329 group (15 vs 8 days, P = .05), whereas time to bacteremia clearance (29 [22-45] vs 25 [20-29] hours, P = .15) and toxicity incidence (13% vs 4%, P = 1) were similar between groups. Conclusions: This study identified a VAN AUC threshold of <329 to be predictive of clinical failure in patients with streptococcal bacteremia which should be interpreted as hypothesis-generating. Studies evaluating VAN AUC-based monitoring for streptococcal bloodstream infections along with other infection types are needed before implementation into clinical practice can be recommended.

Impact of concomitant fluconazole on direct oral anticoagulant bleeding risk.

STUDY OBJECTIVE: The aim of this study was to evaluate the effect on bleeding risk when fluconazole is administered concomitantly with direct oral anticoagulants (DOACs). DESIGN: This was a retrospective cohort study including hospitalized adult patients prescribed a DOAC with or without fluconazole. SETTING: The Ohio State University Wexner Medical Center, a tertiary care academic medical center with more than 1800 beds. PATIENTS: Hospitalized patients ages 18-89 years who received apixaban or rivaroxaban with or without fluconazole from October 1, 2016, to September 30, 2021, were included. The minimum duration of DOAC or DOAC with fluconazole therapy was 48 h. Patients were excluded if they received fluconazole <400 mg daily or a DOAC at doses outside those recommended for atrial fibrillation or venous thromboembolism treatment or prophylaxis. Patients were matched based on DOAC received. INTERVENTION: Patients who received a DOAC with fluconazole were compared with those receiving a DOAC alone. The primary outcome was a composite of major, clinically relevant nonmajor, and minor bleeding events at 30 days. MEASUREMENTS AND MAIN RESULTS: There were 216 patients included, 108 in the DOAC with fluconazole group and 108 in the DOAC alone group. More patients in the DOAC with fluconazole group experienced bleeding at 30 days compared with the DOAC alone group [35/108 (32%) vs. 21/108 (19%), respectively; p = 0.03]; however, after adjusting for proven confounding variables (hemoglobin and concomitant carvedilol) this was found not to be statistically significant [adjusted odds ratio 1.71, 95% confidence interval 0.85-3.40]. CONCLUSIONS: Patients receiving a DOAC with fluconazole were not at significantly increased risk for bleeding at 30 days compared with those receiving a DOAC alone after controlling for confounding variables. As an increasing number of patients are prescribed DOACs, the results of this study may inform clinical decision-making on the safety of concomitant DOAC and fluconazole use.

Identification of Everyday Sounds Affects Their Pleasantness.

This study examines the role of source identification in the emotional response to everyday sounds. Although it is widely acknowledged that sound identification modulates the unpleasantness of sounds, this assumption is based on sparse evidence on a select few sounds. We gathered more robust evidence by having listeners judge the causal properties of sounds, such as actions, materials, and causal agents. Participants also identified and rated the pleasantness of the sounds. We included sounds from a variety of emotional categories, such as Neutral, Misophonic, Unpleasant, and Pleasant. The Misophonic category consists of everyday sounds that are uniquely distressing to a subset of listeners who suffer from Misophonia. Sounds from different emotional categories were paired together based on similar causal properties. This enabled us to test the prediction that a sound's pleasantness should increase or decrease if it is misheard as being in a more or less pleasant emotional category, respectively. Furthermore, we were able to induce more misidentifications by imposing spectral degradation in the form of envelope vocoding. Several instances of misidentification were obtained, all of which showed pleasantness changes that agreed with our predictions.

Clinical Outcomes of Daptomycin Versus Anti-Staphylococcal Beta-Lactams in Definitive Treatment of Methicillin-susceptible Staphylococcus aureus Bloodstream Infections.

OBJECTIVES: Staphylococcus aureus (S. aureus) is the leading cause of bacteraemia and infective endocarditis worldwide. The preferred management of patients with methicillin-susceptible S. aureus (MSSA) bacteraemia includes definitive therapy with intravenous anti-staphylococcal beta-lactam (ASBL) antibiotics. Daptomycin (DAP) has been targeted as a viable substitute for beta-lactam allergic or intolerant patients. METHODS: This single-center retrospective cohort study assessed clinical outcomes of DAP compared with ASBL antibiotics [nafcillin (NAF) or cefazolin (CFZ)] for the treatment of MSSA bacteraemia in patients hospitalised from 01 November 2011 to 31 October 2018. The primary outcome was a composite of the following: clinical failure, MSSA recurrence and MSSA persistence or inpatient infection-related mortality. Secondary outcomes included duration of MSSA bacteraemia, infection-related length of stay, infection-related 90-day readmission, 30-day all-cause mortality, and adverse events necessitating a change in therapy. RESULTS: Of 89 patients with MSSA bacteraemia who were included: 29 received DAP, 30 received NAF and 30 received CFZ. There was no difference in the composite primary outcome in patients treated with DAP compared with ASBL (10% vs. 5%, P = 0.39). The DAP cohort had a longer hospital length of stay compared with the ASBL group (20 days vs. 11.5 days, P = 0.0007). No differences were detected between other secondary outcomes. CONCLUSION: This study suggests that DAP may serve as a comparable alternative to ASBLs for treatment of MSSA bacteraemia, as no differences in clinical outcomes were identified. Larger studies are needed to confirm these findings.

Enhancing Engineering Ethics: Role Ethics and Corporate Social Responsibility.

Engineering ethics calls the attention of engineers to professional codes of ethical responsibility and personal values, but the practice of ethics in corporate settings can be more complex than either of these. Corporations too have cultures that often include corporate social responsibility (CSR) practices and policies, but few discussions of engineering ethics make any explicit reference to CSR. This article proposes critical attention to CSR and role ethics as an opportunity to help prepare engineers to think through the ethics of their professional practice. After a brief overview of the evolution of social responsibility within engineering ethics in the United States, this article shares empirical research with practicing engineers in the mining and energy industries to explore how their formal ethics training did and did not prepare them to grapple with the ethical dimensions of their professional practice. It then illustrates the ways in which these dilemmas and the strategies employed for navigating them are framed within CSR policies and practices and resonate more strongly with role ethics rather than ethical theory as currently taught in most US engineering programs. The article concludes that engineering ethics teaching and learning would benefit from explicitly incorporating critical discussions of role ethics and CSR.

The genetic background significantly impacts the severity of kidney cystic disease in the Pkd1RC/RC mouse model of autosomal dominant polycystic kidney disease.

Autosomal dominant polycystic kidney disease (ADPKD), primarily due to PKD1 or PKD2 mutations, causes progressive kidney cyst development and kidney failure. There is significant intrafamilial variability likely due to the genetic background and environmental/lifestyle factors; variability that can be modeled in PKD mice. Here, we characterized mice homozygous for the PKD1 hypomorphic allele, p.Arg3277Cys (Pkd1RC/RC), inbred into the BALB/cJ (BC) or the 129S6/SvEvTac (129) strains, plus F1 progeny bred with the previously characterized C57BL/6J (B6) model; F1(BC/B6) or F1(129/B6). By one-month cystic disease in both the BC and 129 Pkd1RC/RC mice was more severe than in B6 and continued with more rapid progression to six to nine months. Thereafter, the expansive disease stage plateaued/declined, coinciding with increased fibrosis and a clear decline in kidney function. Greater severity correlated with more inter-animal and inter-kidney disease variability, especially in the 129-line. Both F1 combinations had intermediate disease severity, more similar to B6 but progressive from one-month of age. Mild biliary dysgenesis, and an early switch from proximal tubule to collecting duct cysts, was seen in all backgrounds. Preclinical testing with a positive control, tolvaptan, employed the F1(129/B6)-Pkd1RC/RC line, which has moderately progressive disease and limited isogenic variability. Magnetic resonance imaging was utilized to randomize animals and provide total kidney volume endpoints; complementing more traditional data. Thus, we show how genetic background can tailor the Pkd1RC/RC model to address different aspects of pathogenesis and disease modification, and describe a possible standardized protocol for preclinical testing.

Effectiveness of fidaxomicin versus oral vancomycin in the treatment of recurrent clostridioides difficile.

WHAT IS KNOWN AND OBJECTIVE: The 2017 IDSA/SHEA Clinical Practice Guidelines for Clostridioides difficile infection (CDI) recommend treating recurrent episodes with fidaxomicin or oral vancomycin, but there is little evidence to support one strategy over another, particularly beyond the first recurrence. The aim of this study was to compare clinical outcomes in patients with recurrent CDI treated with vancomycin vs. fidaxomicin. METHODS: This retrospective study evaluated inpatients with recurrent CDI treated with vancomycin or fidaxomicin between 1 January 2013 and 1 May 2019. The primary outcome was CDI recurrence. Secondary outcomes included re-infection, treatment failure, infection-related length of stay (IRLOS) and in-hospital all-cause mortality (IHACM). The Wilcoxon rank-sum test, Pearson's chi-square test or Fisher's exact test was utilized, as appropriate. A multivariable logistic regression (MLR) model was used to estimate the adjusted odds ratio and 95% confidence interval assessing recurrence while adjusting for confounding variables. A survival analysis was also conducted. RESULTS: 135 patients met the inclusion criteria (35 fidaxomicin vs. 100 vancomycin). There was no difference in CDI recurrence [7 (20%) fidaxomicin vs. 11 (11%) vancomycin, p = 0.18]; this persisted in the MLR model (OR: 0.85 [95% CI 0.27-2.7]) and survival analysis (p = 0.1954). Additionally, there was no difference in re-infection rate (p = 0.73), treatment failure (p = 0.13), IRLOS (p = 0.19) or IHACM (p = 0.65). WHAT IS NEW AND CONCLUSION: This represents the first analysis of CDI recurrence that included patients with >2 prior episodes of CDI. The study found no difference in additional recurrences when patients were treated with oral vancomycin vs fidaxomicin for recurrent CDI. However, the current study is limited by the small sample size available for inclusion. Prospective randomized studies with larger sample sizes are needed to confirm this study's conclusions.

Safety outcomes with high-dose daptomycin in patients with acute kidney injury and/or end-stage renal disease.

WHAT IS KNOWN: Daptomycin is associated with a number of adverse effects including eosinophilic pneumonia, hypersensitivity reaction, myopathy, rhabdomyolysis, headache and transaminitis. The adverse effects of high-dose daptomycin have not been fully evaluated in patients with end-stage renal disease (ESRD). OBJECTIVE: To determine the incidence and characteristics of significant adverse effects in patients receiving high-dose daptomycin with severe renal dysfunction. METHODS: A single-centre, retrospective study was conducted to assess safety outcomes of high-dose daptomycin in patients with an estimated creatinine clearance less than 30 mL/min. Adult patients aged 18 to 89 years admitted between 1 July 2015 and 1 July 2019 were eligible for inclusion. Patients must have received definitive daptomycin therapy with doses greater than or equal to 7.5 mg/kg based on actual body weight. The primary outcome was overall incidence of creatine phosphokinase (CK) elevation, myopathy and rhabdomyolysis. RESULTS AND DISCUSSION: A total of 74 patients who received daptomycin therapy were screened with 50 included in the study. The population was well distributed in terms of gender (48% male, n = 24) with a median age of 61 (IQR, 48-67) years. The primary indication for daptomycin use was Gram-positive bacteremia. The median daptomycin dose was 750 (IQR, 600-875) mg, or 8.46 (IQR, 7.92-9.96) mg/kg based on actual body weight, with a median patient weight of 81 (IQR, 65-113) kg. The median duration of therapy was 27 (IQR, 14-42) days. One patient experienced significant CK elevation while on daptomycin therapy with rhabdomyolysis; however, daptomycin was continued as there was an alternative explanation for an elevated CK. One patient experienced daptomycin discontinuation due to CK elevation without meeting the definition for significant CK elevation. WHAT IS NEW AND CONCLUSION: In a cohort of patients with severe renal dysfunction treated with daptomycin 7.5 mg/kg or greater, significant CK elevation on daptomycin therapy was infrequently observed. Future research should confirm these findings, with special consideration for higher mg/kg dosages and/or obese populations.

Disrupting polycystin-2 EF hand Ca2+ affinity does not alter channel function or contribute to polycystic kidney disease.

Approximately 15% of autosomal dominant polycystic kidney disease (ADPKD) is caused by variants in PKD2PKD2 encodes polycystin-2, which forms an ion channel in primary cilia and endoplasmic reticulum (ER) membranes of renal collecting duct cells. Elevated internal Ca2+ modulates polycystin-2 voltage-dependent gating and subsequent desensitization - two biophysical regulatory mechanisms that control its function at physiological membrane potentials. Here, we refute the hypothesis that Ca2+ occupancy of the polycystin-2 intracellular EF hand is responsible for these forms of channel regulation, and, if disrupted, results in ADPKD. We identify and introduce mutations that attenuate Ca2+-EF hand affinity but find channel function is unaltered in the primary cilia and ER membranes. We generated two new mouse strains that harbor distinct mutations that abolish Ca2+-EF hand association but do not result in a PKD phenotype. Our findings suggest that additional Ca2+-binding sites within polycystin-2 or Ca2+-dependent modifiers are responsible for regulating channel activity.

Synergistic Genetic Interactions between Pkhd1 and Pkd1 Result in an ARPKD-Like Phenotype in Murine Models.

BACKGROUND: Autosomal recessive polycystic kidney disease (ARPKD) and autosomal dominant polycystic kidney disease (ADPKD) are genetically distinct, with ADPKD usually caused by the genes PKD1 or PKD2 (encoding polycystin-1 and polycystin-2, respectively) and ARPKD caused by PKHD1 (encoding fibrocystin/polyductin [FPC]). Primary cilia have been considered central to PKD pathogenesis due to protein localization and common cystic phenotypes in syndromic ciliopathies, but their relevance is questioned in the simple PKDs. ARPKD's mild phenotype in murine models versus in humans has hampered investigating its pathogenesis. METHODS: To study the interaction between Pkhd1 and Pkd1, including dosage effects on the phenotype, we generated digenic mouse and rat models and characterized and compared digenic, monogenic, and wild-type phenotypes. RESULTS: The genetic interaction was synergistic in both species, with digenic animals exhibiting phenotypes of rapidly progressive PKD and early lethality resembling classic ARPKD. Genetic interaction between Pkhd1 and Pkd1 depended on dosage in the digenic murine models, with no significant enhancement of the monogenic phenotype until a threshold of reduced expression at the second locus was breached. Pkhd1 loss did not alter expression, maturation, or localization of the ADPKD polycystin proteins, with no interaction detected between the ARPKD FPC protein and polycystins. RNA-seq analysis in the digenic and monogenic mouse models highlighted the ciliary compartment as a common dysregulated target, with enhanced ciliary expression and length changes in the digenic models. CONCLUSIONS: These data indicate that FPC and the polycystins work independently, with separate disease-causing thresholds; however, a combined protein threshold triggers the synergistic, cystogenic response because of enhanced dysregulation of primary cilia. These insights into pathogenesis highlight possible common therapeutic targets.

Monoallelic Mutations to DNAJB11 Cause Atypical Autosomal-Dominant Polycystic Kidney Disease.

Autosomal-dominant polycystic kidney disease (ADPKD) is characterized by the progressive development of kidney cysts, often resulting in end-stage renal disease (ESRD). This disorder is genetically heterogeneous with ∼7% of families genetically unresolved. We performed whole-exome sequencing (WES) in two multiplex ADPKD-like pedigrees, and we analyzed a further 591 genetically unresolved, phenotypically similar families by targeted next-generation sequencing of 65 candidate genes. WES identified a DNAJB11 missense variant (p.Pro54Arg) in two family members presenting with non-enlarged polycystic kidneys and a frameshifting change (c.166_167insTT) in a second family with small renal and liver cysts. DNAJB11 is a co-factor of BiP, a key chaperone in the endoplasmic reticulum controlling folding, trafficking, and degradation of secreted and membrane proteins. Five additional multigenerational families carrying DNAJB11 mutations were identified by the targeted analysis. The clinical phenotype was consistent in the 23 affected members, with non-enlarged cystic kidneys that often evolved to kidney atrophy; 7 subjects reached ESRD from 59 to 89 years. The lack of kidney enlargement, histologically evident interstitial fibrosis in non-cystic parenchyma, and recurring episodes of gout (one family) suggested partial phenotypic overlap with autosomal-dominant tubulointerstitial diseases (ADTKD). Characterization of DNAJB11-null cells and kidney samples from affected individuals revealed a pathogenesis associated with maturation and trafficking defects involving the ADPKD protein, PC1, and ADTKD proteins, such as UMOD. DNAJB11-associated disease is a phenotypic hybrid of ADPKD and ADTKD, characterized by normal-sized cystic kidneys and progressive interstitial fibrosis resulting in late-onset ESRD.

Usability evaluation of a commercial inpatient portal.

OBJECTIVES: Patient portals designed for inpatients have potential to increase patient engagement. However, little is known about how patients use inpatient portals. To address this gap, we aimed to understand how users 1) interact with, 2) learn to use, and 3) communicate with their providers through an inpatient portal. MATERIALS AND METHODS: We conducted a usability evaluation using think-aloud protocol to study user interactions with a commercially available inpatient portal - MyChart Bedside (MCB). Study participants (n=19) were given a tablet that had MCB installed. They explored MCB and completed eight assigned tasks. Each session's recordings were coded and analyzed. We analyzed task completion, errors, and user feedback. We categorized errors into operational errors, system errors, and tablet-related errors, and indicated their violations of Nielsen's ten heuristic principles. RESULTS: Participants frequently made operational errors with most in navigation and assuming non-existent functionalities. We also noted that participants' learning styles varied, with age as a potential factor that influenced how they learned MCB. Also, participants preferred to individually message providers and wanted feedback on status. CONCLUSION: The design of inpatient portals can greatly impact how patients navigate and comprehend information in inpatient portals; poor design can result in a frustrating user experience. For inpatient portals to be effective in promoting patient engagement, it remains critical for technology developers and hospital administrators to understand how users interact with this technology and the resources that may be necessary to support its use.

Engineering Students' Views of Corporate Social Responsibility: A Case Study from Petroleum Engineering.

The mining and energy industries present unique challenges to engineers, who must navigate sometimes competing responsibilities and codes of conduct, such as personal senses of right and wrong, professional ethics codes, and their employers' corporate social responsibility (CSR) policies. Corporate social responsibility (CSR) is the current dominant framework used by industry to conceptualize firms' responsibilities to their stakeholders, yet has it plays a relatively minor role in engineering ethics education. In this article, we report on an interdisciplinary pedagogical intervention in a petroleum engineering seminar that sought to better prepare engineering undergraduate students to critically appraise the strengths and limitations of CSR as an approach to reconciling the interests of industry and communities. We find that as a result of the curricular interventions, engineering students were able to expand their knowledge of the social, rather than simply environmental and economic dimensions of CSR. They remained hesitant, however, in identifying the links between those social aspects of CSR and their actual engineering work. The study suggests that CSR may be a fruitful arena from which to illustrate the profoundly sociotechnical dimensions of the engineering challenges relevant to students' future careers.

Three-dimensional structural dynamics and fluctuations of DNA-nanogold conjugates by individual-particle electron tomography.

DNA base pairing has been used for many years to direct the arrangement of inorganic nanocrystals into small groupings and arrays with tailored optical and electrical properties. The control of DNA-mediated assembly depends crucially on a better understanding of three-dimensional structure of DNA-nanocrystal-hybridized building blocks. Existing techniques do not allow for structural determination of these flexible and heterogeneous samples. Here we report cryo-electron microscopy and negative-staining electron tomography approaches to image, and three-dimensionally reconstruct a single DNA-nanogold conjugate, an 84-bp double-stranded DNA with two 5-nm nanogold particles for potential substrates in plasmon-coupling experiments. By individual-particle electron tomography reconstruction, we obtain 14 density maps at ∼2-nm resolution. Using these maps as constraints, we derive 14 conformations of dsDNA by molecular dynamics simulations. The conformational variation is consistent with that from liquid solution, suggesting that individual-particle electron tomography could be an expected approach to study DNA-assembling and flexible protein structure and dynamics.

The everyday lives of energy transitions: Contested sociotechnical imaginaries in the American West.

This article brings together two growing literatures - on sociotechnical imaginaries in science and technology studies and on resource materialities in anthropology - to explore how two energy-producing communities in the American West understand the moral salience of energy systems and the place of labor within them. Studies of energy sociotechnical imaginaries overwhelmingly focus on the role that state and transnational actors play in shaping perceptions of the 'good society', rather than how these imaginaries inform and are transformed in the lived experience of everyday people. We illuminate the contested dimension of sociotechnical imaginaries and their positioning within structures of power that inform visions of moral behavior and social order. Whereas the role of energy in national imaginaries is grounded almost entirely in the consumption it enables, examining the everyday ethics of people who live and work in Colorado's uranium-rich Western Slope and Wyoming's coal-rich Powder River Basin reveals an insistence that 'good' energy systems also provide opportunities for dignified and well-paid blue-collar work. This imaginary, we argue, remains 'bounded' at a local scale rather than circulating more widely to gain national or international traction. Theorizing this boundedness illustrates not only the contested nature of sociotechnical imaginaries, but also the constraints that material assemblages and sediments of the past place on imagined futures.

Reversible Aptamer-Au Plasmon Rulers for Secreted Single Molecules.

Plasmon rulers, consisting of pairs of gold nanoparticles, allow single-molecule analysis without photobleaching or blinking; however, current plasmon rulers are irreversible, restricting detection to only single events. Here, we present a reversible plasmon ruler, comprised of coupled gold nanoparticles linked by a single aptamer, capable of binding individual secreted molecules with high specificity. We show that the binding of target secreted molecules to the reversible plasmon ruler is characterized by single-molecule sensitivity, high specificity, and reversibility. Such reversible plasmon rulers should enable dynamic and adaptive live-cell measurement of secreted single molecules in their local microenvironment.

The biology of IQGAP proteins: beyond the cytoskeleton.

IQGAP scaffold proteins are evolutionarily conserved in eukaryotes and facilitate the formation of complexes that regulate cytoskeletal dynamics, intracellular signaling, and intercellular interactions. Fungal and mammalian IQGAPs are implicated in cytokinesis. IQGAP1, IQGAP2, and IQGAP3 have diverse roles in vertebrate physiology, operating in the kidney, nervous system, cardio-vascular system, pancreas, and lung. The functions of IQGAPs can be corrupted during oncogenesis and are usurped by microbial pathogens. Therefore, IQGAPs represent intriguing candidates for novel therapeutic agents. While modulation of the cytoskeletal architecture was initially thought to be the primary function of IQGAPs, it is now clear that they have roles beyond the cytoskeleton. This review describes contributions of IQGAPs to physiology at the organism level.