Selective Chemical Inhibition of PGC-1α Gluconeogenic Activity Ameliorates Type 2 Diabetes.

Type 2 diabetes (T2D) is a worldwide epidemic with a medical need for additional targeted therapies. Suppression of hepatic glucose production (HGP) effectively ameliorates diabetes and can be exploited for its treatment. We hypothesized that targeting PGC-1α acetylation in the liver, a chemical modification known to inhibit hepatic gluconeogenesis, could be potentially used for treatment of T2D. Thus, we designed a high-throughput chemical screen platform to quantify PGC-1α acetylation in cells and identified small molecules that increase PGC-1α acetylation, suppress gluconeogenic gene expression, and reduce glucose production in hepatocytes. On the basis of potency and bioavailability, we selected a small molecule, SR-18292, that reduces blood glucose, strongly increases hepatic insulin sensitivity, and improves glucose homeostasis in dietary and genetic mouse models of T2D. These studies have important implications for understanding the regulatory mechanisms of glucose metabolism and treatment of T2D.

Advancing Biological Understanding and Therapeutics Discovery with Small-Molecule Probes.

Small-molecule probes can illuminate biological processes and aid in the assessment of emerging therapeutic targets by perturbing biological systems in a manner distinct from other experimental approaches. Despite the tremendous promise of chemical tools for investigating biology and disease, small-molecule probes were unavailable for most targets and pathways as recently as a decade ago. In 2005, the NIH launched the decade-long Molecular Libraries Program with the intent of innovating in and broadening access to small-molecule science. This Perspective describes how novel small-molecule probes identified through the program are enabling the exploration of biological pathways and therapeutic hypotheses not otherwise testable. These experiences illustrate how small-molecule probes can help bridge the chasm between biological research and the development of medicines but also highlight the need to innovate the science of therapeutic discovery.

Prevalence of iron deficiency and anemia in pediatric heart transplant recipients.

INTRODUCTION: The prevalence of iron deficiency and anemia in the setting of modern-day maintenance immunosuppression in pediatric heart transplant (HTx) recipients is unclear. The primary aim was to determine the prevalence of iron deficiency (serum ferritin < 30 ng/mL ± transferrin saturation < 20%) and anemia per World Health Organization diagnostic criteria and associated risk factors. METHODS: Single-center, cross-sectional analysis of 200 consecutive pediatric HTx recipients (<21 years old) from 2005 to 2021. Data were collected at 1-year post-HTx at the time of annual protocol biopsy. RESULTS: Median age at transplant was 3 years (IQR .5-12.2). The median ferritin level was 32 ng/mL with 46% having ferritin < 30 ng/mL. Median transferrin saturation (TSAT) was 22% with 47% having TSAT < 20%. Median hemoglobin was 11 g/dL with 54% having anemia. Multivariable analysis revealed lower absolute lymphocyte count, TSAT < 20%, and estimated glomerular filtration rate <75 mL/min/1.73 m2 were independently associated with anemia. Ferritin < 30 ng/mL in isolation was not associated with anemia. Ferritin < 30 ng/mL may aid in detecting absolute iron deficiency while TSAT < 20% may be useful in identifying patients with functional iron deficiency ± anemia in pediatric HTx recipients. CONCLUSION: Iron deficiency and anemia are highly prevalent in pediatric HTx recipients. Future studies are needed to assess the impact of iron deficiency, whether with or without anemia, on clinical outcomes in pediatric HTx recipients.

Preoperative dietitian-led Very Low Calorie Diet (VLCD) Clinic for adults living with obesity undergoing gynaecology, laparoscopic cholecystectomy and hernia repair procedures: a pilot parallel randomised controlled trial.

Obesity can increase the risk of postoperative complications. Despite increased demand for patients living with obesity to lose weight prior to common surgical procedures, the impact of intentional weight loss on surgical outcomes is largely unknown. We aimed to conduct a pilot study to assess the feasibility of a full-scale randomised controlled trial (RCT) to examine the effect of preoperative dietitian-led Very Low Calorie Diet (VLCD) Clinic on surgical outcomes in gynaecology and general surgeries. Between August 2021 and January 2023, a convenience sample of adults living with obesity (BMI ≥ 30 kg/m2) awaiting gynaecology, laparoscopic cholecystectomy and ventral hernia repair procedures were randomised to dietitian-led VLCD (800-1000 kcal using meal replacements and allowed foods), or control (no dietary intervention), 2-12 weeks preoperatively. Primary outcome was feasibility (recruitment, adherence, safety, attendance, acceptability and quality of life (QoL)). Secondary outcomes were anthropometry and 30-d postoperative outcomes. Outcomes were analysed as intention-to-treat. Fifty-one participants were recruited (n 23 VLCD, n 28 control), mean 48 (sd 13) years, 86 % female, and mean BMI 35·8 (sd 4·6) kg/m2. Recruitment was disrupted by COVID-19, but other thresholds for feasibility were met for VLCD group: high adherence without unfavourable body composition change, high acceptability, improved pre/post QoL (22·1 ± 15 points, < 0·001), with greater reductions in weight (-5·5 kg VLCD v. -0·9 kg control, P < 0·05) waist circumference (-6·6 cm VLCD v. +0·6 control, P < 0·05) and fewer 30-d complications (n 4/21) than controls (n 8/22) (P > 0·05). The RCT study design was deemed feasible in a public hospital setting. The dietitian-led VLCD resulted in significant weight loss and waist circumference reduction compared with a control group, without unfavourable body composition change and improved QoL.

'The big value of it is getting the patient seen by the right person at the right time': clinician perceptions of the value of allied health primary contact models of care.

Allied health primary contact clinic models of care have increasingly been used as a strategy to increase public health service capacity. A recent systematic review found little consistency or agreement on how primary contact clinics are evaluated. The concept of value of primary contact clinics, which has important implications for evaluation, has not yet been explored in-depth. To explore allied health clinicians' perceptions of the value of allied health primary contact clinics, with the goal of informing an evaluation framework, a descriptive qualitative approach utilizing semi-structured interviews was employed. Participants included allied health staff embedded in clinical lead roles within primary contact clinics across four acute care hospitals in a metropolitan health service located in South-East Queensland, Australia. Lead staff from 30 identified primary contact clinic models in the health service were approached to take part via email. All eligible participants who provided consent were included. An inductive thematic analysis approach was used. A total of 23 clinicians (n = 23) representing 22 diverse models of primary contact clinics participated. Most participants were physiotherapists, dietitians, or occupational therapists, although speech pathology, audiology, and podiatry were also represented. Participant perceptions of the 'value' of PCCs were a highly complex phenomenon, comprising five intersecting domains: (i) patient satisfaction; (ii) clinical outcomes; (iii) care pathway and resource use; (iv) health service performance; and (v) staff satisfaction and professional standing. These five core value domains were positively or negatively influenced by 12 perceived benefits and 8 perceived drawbacks, respectively. Value domains were also highly interrelated and impacted upon each other. The concept of 'value' relating to primary contact clinics involves multiple intersecting domains encompassing different perspectives. This study highlighted potential benefits and drawbacks of primary contact clinics that have not yet been measured or explored in the literature, and as such may be useful for healthcare administrators to consider. The findings of this study will inform an evaluation framework including health economics calculator for primary contact clinics.

Hospital-acquired malnutrition: point prevalence, risk identifiers and utility of a digital Dashboard to identify high-risk, long-stay patients in five Australian facilities.

BACKGROUND: There are limited hospital-acquired malnutrition (HAM) studies among the plethora of malnutrition literature, and a few studies utilise electronic medical records to assist with malnutrition care. This study therefore aimed to determine the point prevalence of HAM in long-stay adult patients across five facilities, whether any descriptors could assist in identifying these patients and whether a digital Dashboard accurately reflected 'real-time' patient nutritional status. METHODS: HAM was defined as malnutrition first diagnosed >14 days after hospital admission. Eligible patients were consenting adult (≥18 years) inpatients with a length of stay (LOS) >14 days. Palliative, mental health and intensive care patients were excluded. Descriptive, clinical and nutritional data were collected, including nutritional status, and whether a patient had hospital-acquired malnutrition to determine point prevalence. Descriptive Fisher's exact and analysis of variance (ANOVA) tests were used. RESULTS: Eligible patients (n = 134) were aged 68 ± 16 years, 52% were female and 92% were acute admissions. HAM and malnutrition point prevalence were 4.5% (n = 6/134) and 19% (n = 26/134), respectively. Patients with HAM had 72 days greater LOS than those with malnutrition present on admission (p < 0.001). A high proportion of HAM patients were inpatients at a tertiary facility and longer-stay wards. The Dashboard correctly reflected recent ward dietitian assessments in 94% of patients at one facility (n = 29/31). CONCLUSIONS: HAM point prevalence was 4.5% among adult long-stay patients. Several descriptors may be suitable to screen for at-risk patients in future studies. Digital Dashboards have the potential to explore factors related to HAM.

Analysis of Platelet Function Testing in Children Receiving Aspirin for Antiplatelet Effects.

Aspirin (ASA) remains the most common antiplatelet agent used in children. VerifyNow Aspirin Test® (VN) assesses platelet response to ASA, with therapeutic effect defined by the manufacturer as ≤ 549 aspirin reaction units (ARU). Single-center, observational, analysis of 195 children (< 18 years-old) who underwent first VN between 2015 and 2020. Primary outcome was proportion of patients with ASA biochemical resistance (> 549 ARU). Secondary outcomes included incidence of new clinical thrombotic and bleeding events during ≤ 6 months from VN in those who received ASA monotherapy (n = 113). Median age was 1.8 years. Common indications for ASA included cardiac anomalies or dysfunction (74.8%) and ischemic stroke (22.6%). Median ASA dose before VN was 4.6 mg/kg/day. Mean VN was 471 ARU. ASA biochemical resistance was detected in 14.4% (n = 28). Of 113 patients receiving ASA monotherapy, 14 (12.4%) had a thrombotic event and 2 (1.8%) had a bleeding event. Mean VN was significantly higher at initial testing in patients experiencing thrombotic event compared to those without thrombosis (516 vs 465 ARU, [95% CI: 9.8, 92.2], p = 0.02). Multivariable analysis identified initial VN ASA result ≥ 500 ARU at initial testing as the only significant independent risk factor for thrombosis (p < 0.01). VN testing identifies ASA biochemical resistance in 14.4% of children. VN ASA ≥ 500 ARU rather than ≥ 550 ARU at initial testing was independently associated with increased odds of thrombosis. Designated cut-off of 550 ARU for detecting platelet dysfunction by ASA may need reconsideration in children.

Is the frequency of dietitian support associated with greater clinical improvements in adults with Crohn's disease undertaking exclusive enteral nutrition?

BACKGROUND: Exclusive enteral nutrition (EEN) is considered to be an effective, low-risk therapy in the treatment of Crohn's disease (CD). Frequent dietetic support may assist adults to succeed. The present observational study aimed to compare whether the frequency of dietetic support during EEN therapy was associated with differences in clinical and nutritional outcomes across two gastroenterology inflammatory bowel disease services. Site A provided ≥3 visits plus more if clinically indicated and Site B provided weekly support. METHODS: Eligible patients were adults with active CD recommended to be treated with oral EEN for ≥6 weeks between February 2018 and December 2019. Demographic, anthropometric, clinical, medications, pathology and EEN treatment descriptors were sourced from the medical chart. Descriptive statistics, as well as chi-squared and t tests, were used to compare data between sites. RESULTS: Eighty-four CD patients were eligible (44 ± 14 years, 54% female, baseline Crohn's disease activity index [CDAI] 259.5 ± 113.1, n = 51 Site A) and completed EEN for median (range) 6.1 (1-12) weeks. Most patients (82%, n = 69/84) completed ≥6 weeks of EEN treatment. CDAI score and calprotectin improved across the total sample from pre- to post-EEN by -109.8 ± 92.1 (p < 0.001) and -65 µg g-1 (-65,230 to 4370) (p = 0.002), respectively. Dietitian occasions of service were more frequent at Site B (7 [4-12] occasions vs. 3 [1-8], p < 0.001). However, changes in clinical and biomarker data were similar between sites (p < 0.05). CONCLUSIONS: EEN with regular dietetic input resulted in clinical and biochemical improvements for patients with active CD. Tailoring dietetic support based on the client's needs and preference may achieve clinical improvements similar to providing weekly dietetic support to adults on EEN.

Multi-site evaluation of advanced practice hand therapy clinics for the management of patients with trigger digit.

STUDY DESIGN: Prospective cohort design. BACKGROUND: Patient time on Australian public hospital surgical outpatient department (SOPD) waitlists often exceeds clinical recommendations for chronic hand conditions. Diversion to allied health is an alternative option, however evidence regarding patient and organizational outcomes in hand therapy is lacking. PURPOSE OF THE STUDY: To evaluate clinical and organizational efficacy, patient outcomes and satisfaction of diversion of referrals for patients with trigger digit (TD) from SOPD waitlists to Advanced Practice Hand Therapy (APHT) at 3 Australian hospitals. METHODS: Data was collected from eligible patients with TD through chart reviews and telephone satisfaction surveys. Data included number of patients requiring SOPD review, repeat referral to SOPD in the 12 months following APHT discharge, patient-rated outcomes, satisfaction scores, wait times to SOPD review and conversion to surgery-rates. Mann Whitney-U, t-test, Pearson's chi-squared test and a Binary Logistic Regression analysis were performed. RESULTS: 104 patients completed APHT treatment. Seventy patients (67%) did not require return to the SOPD waitlist. Repeat referral to SOPD within 12 months of APHT discharge occurred for only 1 patient. Patients requiring SOPD review after APHT treatment were seen within target time frames and demonstrated 88% conversion to surgery-rates. Michigan Hand Outcome Questionnaire scores showed greater improvement in those not requiring SOPD review (P< .001~25.9 vs 4.2). Regression analysis identified a negative association between initial total Michigan Hand Outcome Questionnaire scores and unfavorable discharge outcomes (OR 0.96, P= .007). Most (81%-93%) patients indicated satisfaction with the APHT service. CONCLUSION: Diversion of referrals for TD from SOPD to APHT is an effective waitlist management strategy, with the propensity to reduce waiting times, improve patient flow, whilst resulting in favorable clinical and patient-rated outcomes and satisfaction.

Quality of nutritional care provided to patients who develop hospital acquired malnutrition: A study across five Australian public hospitals.

BACKGROUND: Little is known about the nutritional care provided to patients who develop hospital acquired malnutrition (HAM). The present study aimed to describe the quality of nutritional care provided to patients who developed HAM and determine whether this differed by length of stay (LOS). METHODS: A retrospective medical records audit was conducted on adults with LOS > 14 days across five Australian public hospitals from July 2015 to January 2019 who were clinically assessed to have HAM. Descriptors and nutrition-related care data were sourced. Descriptive statistics were conducted. Chi-squared and t-tests were used to compare patient data by LOS ≤ or > 50 days. RESULTS: Eligible patients (n = 208) were 64% male, with median (range) LOS of 51 (15-354) days, body mass index = 26.8 ± 6.2 kg m-2 and mean ± SD age of 65 ± 17 years. Malnutrition screening was first completed a median (range) of 0 (0-31) days after admission, with weekly screening conducted on 29% of patients. Mean (range) time to initial dietitian assessment was 9 (0-87) days and 27 (2-173) days until malnutrition diagnosis. Thirty-seven percent of patients were weighed within 24 h of a dietitian requesting it, and 51% had fluid retention that may have masked further weight loss. Most (91%) patients consumed < 80% of nutrition requirements for > 2 weeks. However, 54% did not receive additional nutrition support (e.g., enteral nutrition), which was not considered by the dietitian in 28% (n = 31/112) of these patients. Only 40% consumed adequate intake prior to discharge. Those with LOS > 50 days (50%, n = 104/208) took 24 days longer to be diagnosed with malnutrition and lost 2.4 kg more body weight during admission (p < 0.010). CONCLUSIONS: Opportunities exist to optimise nutritional care to facilitate the prevention and management of hospital acquired malnutrition in long-stay patients.

Passing the Certified Nurse Educator Exam: Innovative Strategies.

ABSTRACT: Certification in nursing education demonstrates expertise in teaching. The National League for Nursing Certified Nurse Educator credential is a hallmark of excellence. Six academic nurse educators obtained a 100 percent first-time pass rate as the result of a novel cohort model built upon accountability. This article's purpose is to share innovative approaches that can lead to successfully passing the exam.

Attendance rates and characteristics of women with obesity referred to the dietitian for individual weight management advice during pregnancy.

BACKGROUND: Engagement in services to support healthy weight management during pregnancy is poor. A better understanding of those who attend is important in supporting women to participate in preventative health services. AIMS: This retrospective observational study aimed to report attendance rates of pregnant women with obesity (body mass index (BMI) ≥ 30 kg/m2 ) referred to a dietitian between 2012 and 2018 for weight management and describe who was referred and attended. MATERIALS AND METHODS: Demographic, attendance and medical data for women with obesity who were either referred to a dietitian or were not referred were sourced from hospital data. Chi-squared and t-tests were used to compare groups. Binary logistic regression analysis was used to identify characteristics associated with attendance within the referred group. RESULTS: Of 5426 eligible women, 523 were referred to the dietitian, and 4903 women were not referred (Total sample: 29 ± 6 years, 39.0 ± 2.1 weeks gestation at birth). Referred women self-reported a 6.7 kg/m2 higher pre-pregnancy BMI, 7% more were subsequently diagnosed with gestational diabetes mellitus (GDM), and 9% more were induced (P < 0.001) indicating a higher risk of adverse outcomes. Referred women attended a median (range) of 2 (0-8) appointments. The majority (78%) attended ≥1 appointment, and 41% attended ≥3 appointments. Women referred by a midwife (65%) or diagnosed with GDM were 1.9 and 3.0 times more likely to attend, respectively (P < 0.01). Being a smoker was negatively associated with attendance (odds ratio 0.388, P < 0.001). CONCLUSIONS: Pregnant women with obesity referred for dietetic weight management appear at higher risk of adverse outcomes, with most attending ≥1 appointment. Engaging midwives in promoting referrals may increase attendance.

Seven years after Meaningful Use: Physicians' and nurses' experiences with electronic health records.

Although the federal government's Meaningful Use electronic health record (EHR) implementation program resulted in some successes, there have been many challenges. The purpose of this study was to obtain detailed empirical data to better understand physicians' and nurses' experiences with EHRs. We conducted in-depth interviews with 30 physicians and nurses from two large health systems that were focused on attaining Stage 3 Meaningful Use criteria. Thematic framework analysis identified themes related to perceived benefits and challenges with EHR use. Participants appreciated benefits such as real-time patient data and easier access to information. Challenges included lack of interoperability across units, and this seemed to underlie many other noted challenges such as increased workload, insufficient training, and the perceived need for workarounds. Two key findings included mixed messages about trust in the EHR's information and its interference with interpersonal relationships. Results suggest that conservation of resources theory may be a useful strategy for understanding behaviors that enhance or undermine effective EHR use. Implications for policy and practice are discussed.

Correlating chemical sensitivity and basal gene expression reveals mechanism of action.

Changes in cellular gene expression in response to small-molecule or genetic perturbations have yielded signatures that can connect unknown mechanisms of action (MoA) to ones previously established. We hypothesized that differential basal gene expression could be correlated with patterns of small-molecule sensitivity across many cell lines to illuminate the actions of compounds whose MoA are unknown. To test this idea, we correlated the sensitivity patterns of 481 compounds with ∼19,000 basal transcript levels across 823 different human cancer cell lines and identified selective outlier transcripts. This process yielded many novel mechanistic insights, including the identification of activation mechanisms, cellular transporters and direct protein targets. We found that ML239, originally identified in a phenotypic screen for selective cytotoxicity in breast cancer stem-like cells, most likely acts through activation of fatty acid desaturase 2 (FADS2). These data and analytical tools are available to the research community through the Cancer Therapeutics Response Portal.

Building trust: The influence of mentoring behaviors on perceptions of health care managers' trustworthiness.

BACKGROUND: In health care organizations, trust is critical for effective workplace relationships that ensure patient-centered outcomes. Although research has focused on trust in the relationship between patients and clinicians, less is known about what influences workers to trust their managers. An understanding is needed of the specific behaviors that influence health care workers' evaluations of their managers' trustworthiness. Mentoring research focuses on the developmental assistance that a more experienced worker provides to a less experienced worker. Building upon seminal research on mentoring functions, we argue that health care managers can build trust by providing informational (career-related) and interpersonal (psychosocial) support. PURPOSE: The aim of the study was to investigate the influence of health care managers' informational and interpersonal mentoring behaviors on workers' perceptions of their managers' trustworthiness and the mediating role of trustworthiness on trust in the managers. METHODOLOGY/APPROACH: Surveys were completed during work hours by 315 health care workers at an acute care hospital and associated clinics in the Midwest. FINDINGS: Results showed that managers' mentoring behaviors influenced worker perceptions of their managers' trustworthiness, in terms of ability, integrity, and benevolence. Ability partially mediated the relationship between informational mentoring and trust in managers, whereas integrity and benevolence partially mediated the relationship between interpersonal mentoring and trust in managers. PRACTICE IMPLICATIONS: Health care managers can actively build trust through mentoring behaviors that inspire positive assessments of managers' ability, integrity, and benevolence.

Ecology under lake ice.

Winter conditions are rapidly changing in temperate ecosystems, particularly for those that experience periods of snow and ice cover. Relatively little is known of winter ecology in these systems, due to a historical research focus on summer 'growing seasons'. We executed the first global quantitative synthesis on under-ice lake ecology, including 36 abiotic and biotic variables from 42 research groups and 101 lakes, examining seasonal differences and connections as well as how seasonal differences vary with geophysical factors. Plankton were more abundant under ice than expected; mean winter values were 43.2% of summer values for chlorophyll a, 15.8% of summer phytoplankton biovolume and 25.3% of summer zooplankton density. Dissolved nitrogen concentrations were typically higher during winter, and these differences were exaggerated in smaller lakes. Lake size also influenced winter-summer patterns for dissolved organic carbon (DOC), with higher winter DOC in smaller lakes. At coarse levels of taxonomic aggregation, phytoplankton and zooplankton community composition showed few systematic differences between seasons, although literature suggests that seasonal differences are frequently lake-specific, species-specific, or occur at the level of functional group. Within the subset of lakes that had longer time series, winter influenced the subsequent summer for some nutrient variables and zooplankton biomass.

Understanding and Supporting Grieving Adolescents and Young Adults.

The adolescent and young adult years are a time of growth, change, and challenge. Experiencing the loss of a family member or friend during this period of life can have a profound effect on a young person's social functioning, physical and mental health, and development. Research demonstrates that the grief reactions of adolescents and young adults differ from those of adults, and that loss is an individual experience that varies widely throughout each developmental stage. Further, youth who struggle to cope with a significant loss without support and guidance are more likely to experience a greater intensity of grief and distress. When providing support to a grieving adolescent or young adult, it is important to understand normal development, appreciate common grief responses, and identify deviations. It is also important to know about available interventions and supportive strategies, specifically for this age group. With this knowledge, pediatric nurses and other helping professionals can tailor guidance, support, and referrals to suit the specific needs of individual bereaved youth.

Diversity-oriented synthesis probe targets Plasmodium falciparum cytochrome b ubiquinone reduction site and synergizes with oxidation site inhibitors.

BACKGROUND: The emergence and spread of drug resistance to current antimalarial therapies remains a pressing concern, escalating the need for compounds that demonstrate novel modes of action. Diversity-Oriented Synthesis (DOS) libraries bridge the gap between conventional small molecule and natural product libraries, allowing the interrogation of more diverse chemical space in efforts to identify probes of novel parasite pathways. METHODS: We screened and optimized a probe from a DOS library using whole-cell phenotypic assays. Resistance selection and whole-genome sequencing approaches were employed to identify the cellular target of the compounds. RESULTS: We identified a novel macrocyclic inhibitor of Plasmodium falciparum with nanomolar potency and identified the reduction site of cytochrome b as its cellular target. Combination experiments with reduction and oxidation site inhibitors showed synergistic inhibition of the parasite. CONCLUSIONS: The cytochrome b oxidation center is a validated antimalarial target. We show that the reduction site of cytochrome b is also a druggable target. Our results demonstrating a synergistic relationship between oxidation and reduction site inhibitors suggests a future strategy for new combination therapies in the treatment of malaria.

Kinase-Independent Small-Molecule Inhibition of JAK-STAT Signaling.

Phenotypic cell-based screening is a powerful approach to small-molecule discovery, but a major challenge of this strategy lies in determining the intracellular target and mechanism of action (MoA) for validated hits. Here, we show that the small-molecule BRD0476, a novel suppressor of pancreatic ß-cell apoptosis, inhibits interferon-gamma (IFN-γ)-induced Janus kinase 2 (JAK2) and signal transducer and activation of transcription 1 (STAT1) signaling to promote ß-cell survival. However, unlike common JAK-STAT pathway inhibitors, BRD0476 inhibits JAK-STAT signaling without suppressing the kinase activity of any JAK. Rather, we identified the deubiquitinase ubiquitin-specific peptidase 9X (USP9X) as an intracellular target, using a quantitative proteomic analysis in rat ß cells. RNAi-mediated and CRISPR/Cas9 knockdown mimicked the effects of BRD0476, and reverse chemical genetics using a known inhibitor of USP9X blocked JAK-STAT signaling without suppressing JAK activity. Site-directed mutagenesis of a putative ubiquitination site on JAK2 mitigated BRD0476 activity, suggesting a competition between phosphorylation and ubiquitination to explain small-molecule MoA. These results demonstrate that phenotypic screening, followed by comprehensive MoA efforts, can provide novel mechanistic insights into ostensibly well-understood cell signaling pathways. Furthermore, these results uncover USP9X as a potential target for regulating JAK2 activity in cellular inflammation.

The jellification of north temperate lakes.

Calcium (Ca) concentrations are decreasing in softwater lakes across eastern North America and western Europe. Using long-term contemporary and palaeo-environmental field data, we show that this is precipitating a dramatic change in Canadian lakes: the replacement of previously dominant pelagic herbivores (Ca-rich Daphnia species) by Holopedium glacialis, a jelly-clad, Ca-poor competitor. In some lakes, this transformation is being facilitated by increases in macro-invertebrate predation, both from native (Chaoborus spp.) and introduced (Bythotrephes longimanus) zooplanktivores, to which Holopedium, with its jelly coat, is relatively invulnerable. Greater representation by Holopedium within cladoceran zooplankton communities will reduce nutrient transfer through food webs, given their lower phosphorus content relative to daphniids, and greater absolute abundances may pose long-term problems to water users. The dominance of jelly-clad zooplankton will likely persist while lakewater Ca levels remain low.