Patient preferences for breast cancer screening: a systematic review update to inform recommendations by the Canadian Task Force on Preventive Health Care.

BACKGROUND: Different guideline panels, and individuals, may make different decisions based in part on their preferences. Preferences for or against an intervention are viewed as a consequence of the relative importance people place on the expected or experienced health outcomes it incurs. These findings can then be considered as patient input when balancing effect estimates on benefits and harms reported by empirical evidence on the clinical effectiveness of screening programs. This systematic review update examined the relative importance placed by patients on the potential benefits and harms of mammography-based breast cancer screening to inform an update to the 2018 Canadian Task Force on Preventive Health Care's guideline on screening. METHODS: We screened all articles from our previous review (search December 2017) and updated our searches to June 19, 2023 in MEDLINE, PsycINFO, and CINAHL. We also screened grey literature, submissions by stakeholders, and reference lists. The target population was cisgender women and other adults assigned female at birth (including transgender men and nonbinary persons) aged ≥ 35 years and at average or moderately increased risk for breast cancer. Studies of patients with breast cancer were eligible for health-state utility data for relevant outcomes. We sought three types of data, directly through (i) disutilities of screening and curative treatment health states (measuring the impact of the outcome on one's health-related quality of life; utilities measured on a scale of 0 [death] to 1 [perfect health]), and (ii) other preference-based data, such as outcome trade-offs, and indirectly through (iii) the relative importance of benefits versus harms inferred from attitudes, intentions, and behaviors towards screening among patients provided with estimates of the magnitudes of benefit(s) and harms(s). For screening, we used machine learning as one of the reviewers after at least 50% of studies had been reviewed in duplicate by humans; full-text selection used independent review by two humans. Data extraction and risk of bias assessments used a single reviewer with verification. Our main analysis for utilities used data from utility-based health-related quality of life tools (e.g., EQ-5D) in patients; a disutility value of about 0.04 can be considered a minimally important value for the Canadian public. When suitable, we pooled utilities and explored heterogeneity. Disutilities were calculated for screening health states and between different treatment states. Non-utility data were grouped into categories, based on outcomes compared (e.g. for trade-off data), participant age, and our judgements of the net benefit of screening portrayed by the studies. Thereafter, we compared and contrasted findings while considering sample sizes, risk of bias, subgroup findings and data on knowledge scores, and created summary statements for each data set. Certainty assessments followed GRADE guidance for patient preferences and used consensus among at least two reviewers. FINDINGS: Eighty-two studies (38 on utilities) were included. The estimated disutilities were 0.07 for a positive screening result (moderate certainty), 0.03-0.04 for a false positive (FP; "additional testing" resolved as negative for cancer) (low certainty), and 0.08 for untreated screen-detected cancer (moderate certainty) or (low certainty) an interval cancer. At ≤12 months, disutilities of mastectomy (vs. breast-conserving therapy), chemotherapy (vs. none) (low certainty), and radiation therapy (vs. none) (moderate certainty) were 0.02-0.03, 0.02-0.04, and little-to-none, respectively, though in each case findings were somewhat limited in their applicability. Over the longer term, there was moderate certainty for little-to-no disutility from mastectomy versus breast-conserving surgery/lumpectomy with radiation and from radiation. There was moderate certainty that a majority (>50%) and possibly a large majority (>75%) of women probably accept up to six cases of overdiagnosis to prevent one breast-cancer death; there was some uncertainty because of an indication that overdiagnosis was not fully understood by participants in some cases. Low certainty evidence suggested that a large majority may accept that screening may reduce breast-cancer but not all-cause mortality, at least when presented with relatively high rates of breast-cancer mortality reductions (n = 2; 2 and 5 fewer per 1000 screened), and at least a majority accept that to prevent one breast-cancer death at least a few hundred patients will receive a FP result and 10-15 will have a FP resolved through biopsy. An upper limit for an acceptable number of FPs was not evaluated. When using data from studies assessing attitudes, intentions, and screening behaviors, across all age groups but most evident for women in their 40s, preferences reduced as the net benefit presented by study authors decreased in magnitude. In a relatively low net-benefit scenario, a majority of patients in their 40s may not weigh the benefits as greater than the harms from screening whereas for women in their 50s a large majority may prefer screening (low certainty evidence for both ages). There was moderate certainty that a large majority of women 50 years of age and 50 to 69 years of age, who have usually experienced screening, weigh the benefits as greater than the harms from screening in a high net-benefit scenario. A large majority of patients aged 70-71 years who have recently screened probably think the benefits outweigh the harms of continuing to screen. A majority of women in their mid-70s to early 80s may prefer to continue screening. CONCLUSIONS: Evidence across a range of data sources on how informed patients value the potential outcomes from breast-cancer screening will be useful during decision-making for recommendations. The evidence suggests that all of the outcomes examined have importance to women of any age, that there is at least some and possibly substantial (among those in their 40s) variability across and within age groups about the acceptable magnitude of effects across outcomes, and that provision of easily understandable information on the likelihood of the outcomes may be necessary to enable informed decision making. Although studies came from a wide range of countries, there were limited data from Canada and about whether findings applied well across an ethnographically and socioeconomically diverse population. SYSTEMATIC REVIEW REGISTRATION: Protocol available at Open Science Framework https://osf.io/xngsu/ .

The B1 H + -ATPase ( Atp6v1b1 ) Subunit in Non-Type A Intercalated Cells is Required for Driving Pendrin Activity and the Renal Defense Against Alkalosis.

SIGNIFICANCE STATEMENT: In the kidney, the B1 H + -ATPase subunit is mostly expressed in intercalated cells (IC). Its importance in acid-secreting type A ICs is evident in patients with inborn distal renal tubular acidosis and ATP6V1B1 mutations. However, the protein is also highly expressed in alkali-secreting non-type A ICs where its function is incompletely understood. We demonstrate in Atp6v1b1 knock out mice that the B1 subunit is critical for the renal response to defend against alkalosis during an alkali load or chronic furosemide treatment. These findings highlight the importance of non-type A ICs in maintaining acid-base balance in response to metabolic challenges or commonly used diuretics. BACKGROUND: Non-type A ICs in the collecting duct system express the luminal Cl - /HCO 3- exchanger pendrin and apical and/or basolateral H + -ATPases containing the B1 subunit isoform. Non-type A ICs excrete bicarbonate during metabolic alkalosis. Mutations in the B1 subunit (ATP6V1B1) cause distal renal tubular acidosis due to its role in acid secretory type A ICs. The function of B1 in non-type A ICs has remained elusive. METHODS: We examined the responses of Atp6v1b1-/- and Atp6v1b1+/+ mice to an alkali load and to chronic treatment with furosemide. RESULTS: An alkali load or 1 week of furosemide resulted in a more pronounced hypokalemic alkalosis in male ATP6v1b1-/- versus Atp6v1b1+/+ mice that could not be compensated by respiration. Total pendrin expression and activity in non-type A ICs of ex vivo microperfused cortical collecting ducts were reduced, and ß2 -adrenergic stimulation of pendrin activity was blunted in ATP6v1b1-/- mice. Basolateral H + -ATPase activity was strongly reduced, although the basolateral expression of the B2 isoform was increased. Ligation assays for H + -ATPase subunits indicated impaired assembly of V 0 and V 1 H + -ATPase domains. During chronic furosemide treatment, ATP6v1b1-/- mice also showed polyuria and hyperchloremia versus Atp6v1b1+/+ . The expression of pendrin, the water channel AQP2, and subunits of the epithelial sodium channel ENaC were reduced. CONCLUSIONS: Our data demonstrate a critical role of H + -ATPases in non-type A ICs function protecting against alkalosis and reveal a hitherto unrecognized need of basolateral B1 isoform for a proper H + -ATPase complexes assembly and ability to be stimulated.

Blocking FGF23 signaling improves the growth plate of mice with X-linked hypophosphatemia.

Fibroblast growth factor 23 (FGF23) is a phosphaturic hormone. X-linked hypophosphatemia (XLH) is the most prevalent inherited phosphate wasting disorder due to mutations in the PHEX gene, which cause elevated circulating FGF23 levels. Clinically, it is characterized by growth impairment and defective mineralization of bones and teeth. Treatment of XLH is challenging. Since 2018, neutralizing antibodies against FGF23 have dramatically improved the therapy of XLH patients, although not all patients fully respond to the treatment, and it is very costly. C-terminal fragments of FGF23 have recently emerged as blockers of intact FGF23 signaling. Here, we analyzed the effect on growth and bone of a short 26 residues long C-terminal FGF23 (cFGF23) fragment and two N-acetylated and C-amidated cFGF23 peptides using young XLH mice (Phex C733RMhda mice). Although no major changes in blood parameters were observed after 7 days of treatment with these peptides, bone length and growth plate structure improved. The modified peptides accelerated the growth rate probably by improving growth plate structure and dynamics. The processes of chondrocyte proliferation, death, hypertrophy, and the cartilaginous composition in the growth plate were partially improved in young treated XLH mice. In conclusion, these findings contribute to understand the role of FGF23 signaling in growth plate metabolism and show that this may occur despite continuous hypophosphatemia.

Severe obesity and global developmental delay in preschool children: Findings from a Canadian Paediatric Surveillance Program study.

Background: The co-presentation of severe obesity (SO) and global developmental delay (GDD) in Canadian preschool children has not been examined. However, SO and GDD may require syndromic diagnoses and unique management considerations. Objectives: To determine (1) minimum incidence; (2) age of onset and risk factors; and (3) health care utilization for co-presenting SO and GDD. Methods: Through the Canadian Paediatric Surveillance Program (CPSP), a monthly form was distributed to participants from February 2018 to January 2020 asking for reports of new cases of SO and GDD among children ≤5 years of age. We performed descriptive statistics for quantitative questions and qualitative content analysis for open-ended questions. Results: Forty-seven cases (64% male; 51% white; mean age: 3.5 ± 1.2 years) were included. Age of first weight concern was 2.5 ± 1.3 years and age of GDD diagnosis was 2.7 ± 1.4 years. Minimum incidence of SO and GDD was 3.3 cases per 100,000 for ≤5 years of age per year. Identified problems included school and/or behavioural problems (n = 17; 36%), snoring (n = 14; 30%), and asthma/recurrent wheeze (n = 10; 21%). Mothers of 32% of cases (n = 15) had obesity and 21% of cases (n = 10) received neonatal intensive care. Microarray was ordered for 57% (n = 27) of children. A variety of clinicians and services were accessed. As reported by CPSP participants, challenges faced by families and health service access were barriers to care. Conclusion: Children with SO and GDD have multiple comorbidities, and require early identification and referral to appropriate services. These cases may also benefit from additional testing to rule out known genetic obesity syndromes.

The application and reporting of motivational interviewing in managing adolescent obesity: A scoping review and stakeholder consultation.

Motivational interviewing (MI) is an evidence-based counseling approach that can help individuals make positive behavioral and cognitive changes for managing obesity. We conducted a scoping review to summarize evidence on fidelity and key elements of MI-based interventions for managing adolescent obesity and examine the reporting of these interventions. Ten electronic databases and gray literature were searched systematically and included literature from January 1983 to February 2022, and 26 studies were included. Data on MI features, delivery context, training, and fidelity to treatment were summarized. Fidelity was assessed using an assessment grid with five domains-theory, training, implementation, treatment receipt, and treatment enactment. The last step of the review involved stakeholder consultation with clinician-scientists and researchers with experience in MI and managing adolescent obesity. Thirteen stakeholders were interviewed about our review findings on MI and treatment fidelity. Our analyses revealed that MI-based interventions for managing adolescent obesity had "low treatment fidelity"; no studies had "high treatment fidelity" across all five domains. Fidelity strategies adhered to the most was theory, and treatment enactment was the lowest. Stakeholders mentioned that "low treatment fidelity" may be due to increased time to complete fidelity assessments and increased cost associated with treatment fidelity. These findings have implications for planning, implementing, and evaluating MI-based interventions for managing adolescent obesity.

Social service providers' perspectives on caring for structurally vulnerable hospital patients who use drugs: a qualitative study.

BACKGROUND: People who use drugs and are structurally vulnerable (e.g., experiencing unstable and/or lack of housing) frequently access acute care. However, acute care systems and providers may not be able to effectively address social needs during hospitalization. Our objectives were to: 1) explore social service providers' perspectives on addressing social needs for this patient population; and 2) identify what possible strategies social service providers suggest for improving patient care. METHODS: We completed 18 semi-structured interviews with social service providers (e.g., social workers, transition coordinators, peer support workers) at a large, urban acute care hospital in Western Canada between August 8, 2018 and January 24, 2019. Interviews explored staff experiences providing social services to structurally vulnerable patients who use drugs, as well as continuity between hospital and community social services. We conducted latent content analysis and organized our findings in relation to the socioecological model. RESULTS: Tensions emerged on how participants viewed patient-level barriers to addressing social needs. Some providers blamed poor outcomes on perceived patient deficits, while others emphasized structural factors that impede patients' ability to secure social services. Within the hospital, some participants felt that acute care was not an appropriate location to address social needs, but most felt that hospitalization affords a unique opportunity to build relationships with structurally vulnerable patients. Participants described how a lack of housing and financial supports for people who use drugs in the community limited successful social service provision in acute care. They identified potential policy solutions, such as establishing housing supports that concurrently address medical, income, and substance use needs. CONCLUSIONS: Broad policy changes are required to improve care for structurally vulnerable patients who use drugs, including: 1) ending acute care's ambivalence towards social services; 2) addressing multi-level gaps in housing and financial support; 3) implementing hospital-based Housing First teams; and, 4) offering sub-acute care with integrated substance use management.

Policy actor views on structural vulnerability in harm reduction and policymaking for illegal drugs: A qualitative study.

BACKGROUND: Health risks associated with drug use are concentrated amongst structurally vulnerable people who use illegal drugs (PWUD). We described how Canadian policy actors view structural vulnerability in relation to harm reduction and policymaking for illegal drugs, and what solutions they suggest to reduce structural vulnerability for PWUD. METHODS: The Canadian Harm Reduction Policy Project is a mixed-method, multiple case study. The qualitative component included 73 semi-structured interviews conducted with harm reduction policy actors across Canada's 13 provinces and territories between November 2016 and December 2017. Interviews explored perspectives on harm reduction and illegal drug policies and the conditions that facilitate or constrain policy change. Our sub-analysis utilized a two-step inductive analytic process. First, we identified transcript segments that discussed structural vulnerability or analogous terms. Second, we conducted latent content analysis on the identified excerpts to generate main findings. RESULTS: The central role of structural vulnerability (including poverty, unstable/lack of housing, racialization) in driving harm for PWUD was acknowledged by participants in all provinces and territories. Criminalization, in particular, was seen as a major contributor to structural vulnerability by justifying formal and informal sanctions against drug use and, by extension, PWUD. Many participants expressed that their personal understanding of harm reduction included addressing the structural conditions facing PWUD, yet identified that formal government harm reduction policies focused solely on drug use rather than structural factors. Participants identified several potential policy solutions to intervene on structural vulnerability including decriminalization, safer supply, and enacting policies encompassing all health and social sectors. CONCLUSIONS: Structural vulnerability is salient within Canadian policy actors' discourses; however, formal government policies are seen as falling short of addressing the structural conditions of PWUD. Decriminalization and safer supply have the potential to mitigate immediate structural vulnerability of PWUD while policies evolve to advance social, economic, and cultural equity.

A survey of stakeholders' perceived importance of health indicators and subgroup analyses to inform the Canadian clinical practice guideline for managing paediatric obesity.

OBJECTIVE: To assess stakeholder ratings of health indicators and subgroup analyses in systematic reviews used to update the Canadian Clinical Practice Guideline for Managing Paediatric Obesity. METHODS: Stakeholders (caregivers of children with obesity and Clinical Practice Guideline Steering Committee members) completed an online survey between April 2020 and March 2021. Participants rated importance of health indicators and subgroup analyses for behavioural and psychological, pharmacotherapeutic, and surgical interventions for managing paediatric obesity from not important to critically important using Grading, Recommendations, Assessment, Development and Evaluation criteria. RESULTS: No health indicators or subgroup analyses were rated not important by the 30 caregivers and 17 Steering Committee members. Across intervention types, stakeholders rated anxiety, depression, health-related quality of life, serious adverse events, plus age and weight status subgroups as critically important. CONCLUSION: Stakeholder ratings will inform data reporting and interpretation to update Canada's Clinical Practice Guideline for Managing Paediatric Obesity.

Resilin is needed for wing posture in Drosophila suzukii.

Resilin is a protein matrix in movable regions of the cuticle conferring resistance to fatigue. The main component of Resilin is Pro-Rresilin that polymerises via covalent di- and tri-tyrosine bounds (DT). Loss of Pro-Resilin is nonlethal and causes a held-down wing phenotype (hdw) in the fruit fly Drosophila melanogaster. To test whether this mild phenotype is recurrent in other insect species, we analysed resilin in the spotted-wing fruit fly Drosophila suzukii. As quantified by DT autofluorescence by microscopy, DT intensities in the trochanter and the wing hinge are higher in D. suzukii than in D. melanogaster, while in the proboscis the DT signal is stronger in D. melanogaster compared to D. suzukii. To study the function of Pro-Resilin in D. suzukii, we generated a mutation in the proresilin gene applying the Crispr/Cas9 technique. D. suzukii pro-resilin mutant flies are flight-less and show a hdw phenotype resembling respective D. melanogaster mutants. DT signal intensity at the wing hinge is reduced but not eliminated in D. suzukii hdw flies. Either residual Pro-Resilin accounts for the remaining DT signal or, as proposed for the hdw phenotype in D. melanogaster, other DT forming proteins might be present in Resilin matrices. Interestingly, DT signal intensity reduction rates in D. suzukii and D. melanogaster are somehow different. Taken together, in general, the function of Pro-Resilin seems to be conserved in the Drosophila genus; small differences in DT quantity, however, allow us to hypothesise that Resilin matrices might be modulated during evolution probably to accommodate the species-specific lifestyle.

Updating the Canadian clinical practice guideline for managing pediatric obesity: a protocol.

BACKGROUND: Since the first national guideline for managing obesity in adults and children in Canada was published in 2007, new evidence has emerged and guideline standards have evolved. Our purpose is to describe the protocol used to update the Canadian clinical practice guideline for managing pediatric obesity. METHODS: This guideline will update the pediatric components of the 2007 Canadian clinical practice guideline for the management of obesity. In partnership with Obesity Canada, we began preliminary work in 2019; activities are scheduled for completion in 2022. The guideline will follow standards developed by the National Academy of Medicine and the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) working group. Guideline development will be informed by 5 complementary literature reviews: a scoping review that focuses on clinical assessment in pediatric obesity management and 4 systematic reviews to synthesize evidence regarding families' values and preferences as well as the safety and effectiveness of interventions (psychological and behavioural; pharmacotherapeutic; and surgical). We will use standard systematic review methodology, including summarizing and assessing the certainty of evidence and determining the strength of recommendations. Competing interests will be managed proactively according to recommendations from the Guidelines International Network. Diverse stakeholders, including families and clinicians, will be engaged throughout guideline development. INTERPRETATION: The guideline will support Canadian families and clinicians to make informed, value-sensitive and evidence-based clinical decisions related to managing pediatric obesity. The guideline and accompanying resources for end-users will be published in English and French, and we will partner with Obesity Canada to optimize dissemination using integrated and end-of-project knowledge translation.

The state of science on including inhalation within supervised consumption services: A scoping review of academic and grey literature.

BACKGROUND: Internationally, many supervised consumption services (SCS) include drug inhalation (smoking). However, most research is focused on SCS for people who inject drugs. We aimed to: (1) synthesize the literature on including inhalation or other forms of non-injection drug use (e.g., oral, intranasal) within SCS; (2) describe the state of the science on the feasibility of this practice and its outcomes; and (3) outline an agenda for future evaluation research in this area. METHODS: We searched 9 academic and 13 grey literature databases and ultimately included 40 studies. Thirty-two studies (80%) reported findings from feasibility or needs assessments. From these studies, we extracted information on willingness to use these services, perspectives of people who use drugs and other stakeholders, and recommendations for implementation. Eight studies (20%) evaluated including inhalation in SCS, from which we extracted data on associated outcomes. Data were analysed using narrative synthesis and descriptive statistics. RESULTS: We found high willingness to use SCS including inhalation among people who use drugs, especially those experiencing structural vulnerability. Research emphasized a need for implementation to account for the social nature of drug inhalation, and to limit potential occupational hazards associated with passive inhalation. Positive outcomes associated with inhalation within SCS included improved health and safety of people who use drugs and decreased public drug use. However, this evidence was based primarily on a limited number of studies with designs of mixed quality. CONCLUSION: Our review demonstrates feasibility of, and need for, implementing SCS including inhalation, and some potential positive outcomes associated with this practice. However, more comprehensive and systematic evaluations of including inhalation as well as other forms of non-injection drug use (e.g., oral, intranasal, rectal) within SCS should be conducted.

Chronic High Phosphate Intake in Mice Affects Macronutrient Utilization and Body Composition.

SCOPE: In the last decades, dietary phosphate intake has increased due to a higher consumption of ultraprocessed food. This higher intake has an impact on body composition and health state. Recently, this study finds that a high chronic phosphate diet leads to no major renal alterations, but negatively affects parameters of bone health probably due to the chronic acid load. Here the effect of high phosphate consumption on parameters of energy metabolism is assessed. METHODS AND RESULTS: Healthy mature adult mice are fed for 1 year or 4 months with either a standard (0.6 % w/w) or a high phosphate (1.2 % w/w) diet. Males and females of two different genetic backgrounds are investigated. Mice feed the high phosphate diet show an attenuated body-weight gain, lower respiratory exchange ratio, decreased body fat mass, and increased lean-to-fat mass ratio. Moreover, the high phosphate diet leads to fasting hypoglycemia with no differences in the glucose response to an oral glucose tolerance test. Triglycerides and cholesterol in blood are similar independently of dietary phosphate content. However, 1-methylhistidine is lower in animals feed a chronic high phosphate intake. CONCLUSIONS: High phosphate diet attenuates body weight gain, but induces hypoglycemia and may alter muscle homeostasis.

Establishing a Working Definition of User Experience for eHealth Interventions of Self-reported User Experience Measures With eHealth Researchers and Adolescents: Scoping Review.

BACKGROUND: Across eHealth intervention studies involving children, adolescents, and their parents, researchers have measured user experience to assist with intervention development, refinement, and evaluation. To date, no widely accepted definitions or measures of user experience exist to support a standardized approach for evaluation and comparison within or across interventions. OBJECTIVE: We conduct a scoping review with subsequent Delphi consultation to identify how user experience is defined and measured in eHealth research studies, characterize the measurement tools used, and establish working definitions for domains of user experience that could be used in future eHealth evaluations. METHODS: We systematically searched electronic databases for published and gray literature available from January 1, 2005, to April 11, 2019. We included studies assessing an eHealth intervention that targeted any health condition and was designed for use by children, adolescents, and their parents. eHealth interventions needed to be web-, computer-, or mobile-based, mediated by the internet with some degree of interactivity. We required studies to report the measurement of user experience as first-person experiences, involving cognitive and behavioral factors reported by intervention users. We appraised the quality of user experience measures in included studies using published criteria: well-established, approaching well-established, promising, or not yet established. We conducted a descriptive analysis of how user experience was defined and measured in each study. Review findings subsequently informed the survey questions used in the Delphi consultations with eHealth researchers and adolescent users for how user experience should be defined and measured. RESULTS: Of the 8634 articles screened for eligibility, 129 articles and 1 erratum were included in the review. A total of 30 eHealth researchers and 27 adolescents participated in the Delphi consultations. On the basis of the literature and consultations, we proposed working definitions for 6 main user experience domains: acceptability, satisfaction, credibility, usability, user-reported adherence, and perceived impact. Although most studies incorporated a study-specific measure, we identified 10 well-established measures to quantify 5 of the 6 domains of user experience (all except for self-reported adherence). Our adolescent and researcher participants ranked perceived impact as one of the most important domains of user experience and usability as one of the least important domains. Rankings between adolescents and researchers diverged for other domains. CONCLUSIONS: Findings highlight the various ways in which user experience has been defined and measured across studies and what aspects are most valued by researchers and adolescent users. We propose incorporating the working definitions and available measures of user experience to support consistent evaluation and reporting of outcomes across studies. Future studies can refine the definitions and measurement of user experience, explore how user experience relates to other eHealth outcomes, and inform the design and use of human-centered eHealth interventions.

Jak1/Stat3 Activation Alters Phosphate Metabolism Independently of Sex and Extracellular Phosphate Levels.

INTRODUCTION: Phosphate homeostasis is regulated by a complex network involving the parathyroid hormone (PTH), fibroblast growth factor 23 (FGF23), and calcitriol acting on several organs including the kidney, intestine, bone, and parathyroid gland. Previously, we showed that activation of the Janus kinase 1 (Jak1)-signal transducer and activator of transcription 3 (Stat3) signaling pathway leads to altered mineral metabolism with higher FGF23 levels, lower PTH, and higher calcitriol levels. Here, we investigated if there are sex differences in the role of Jak1/Stat3 signaling pathway on phosphate metabolism and if this pathway is sensitive to extracellular phosphate alterations. METHODS: We used a mouse model (Jak1S645P+/-) that resembles a constitutive activating mutation of the Jak1/Stat3 signaling pathway in humans and analyzed the impact of sex on mineral metabolism parameters. Furthermore, we challenged Jak1S645P+/- male and female mice with a high (1.2% w/w) and low (0.1% w/w) phosphate diet and a diet with phosphate with organic origin with lower bioavailability. RESULTS: Female mice, as male mice, showed higher intact FGF23 levels but no phosphaturia, and higher calcitriol and lower PTH levels in plasma. A phosphate challenge did not alter the effect of Jak1/Stat3 activation on phosphate metabolism for both genders. However, under a low phosphate diet or a diet with lower phosphate availability, the animals showed a tendency to develop hypophosphatemia. Moreover, male and female mice showed similar phosphate metabolism parameters. The only exception was higher PTH levels in male mice than those in females. DISCUSSION/CONCLUSION: Sex and extracellular phosphate levels do not affect the impact of Jak1/Stat3 activation on phosphate metabolism.

Ratio between Lactobacillus plantarum and Acetobacter pomorum on the surface of Drosophila melanogaster adult flies depends on cuticle melanisation.

OBJECTIVES: As in most organisms, the surface of the fruit fly Drosophila melanogaster is associated with bacteria. To examine whether this association depends on cuticle quality, we isolated and quantified surface bacteria in normal and melanized flies applying a new and simple protocol. RESULTS: On wild flies maintained in the laboratory, we identified two persistently culturable species as Lactobacillus plantarum and Acetobacter pomorum by 16S rDNA sequencing. For quantification, we showered single flies for DNA extraction avoiding the rectum to prevent contamination from the gut. In quantitative PCR analyses, we determined the relative abundance of these two species in surface wash samples. On average, we found 17-times more A. pomorum than L. plantarum. To tentatively study the importance of the cuticle for the interaction of the surface with these bacteria, applying Crispr/Cas9 gene editing in the initial wild flies, we generated flies mutant for the ebony gene needed for cuticle melanisation and determined the L. plantarum to A. pomorum ratio on these flies. We found that the ratio between the two bacterial species reversed on ebony flies. We hypothesize that the cuticle chemistry is crucial for surface bacteria composition. This finding may inspire future studies on cuticle-microbiome interactions.

Systemic Jak1 activation causes extrarenal calcitriol production and skeletal alterations provoking stunted growth.

Mineral homeostasis is regulated by a complex network involving endocrine actions by calcitriol, parathyroid hormone (PTH), and FGF23 on several organs including kidney, intestine, and bone. Alterations of mineral homeostasis are found in chronic kidney disease and other systemic disorders. The interplay between the immune system and the skeletal system is not fully understood, but cytokines play a major role in modulating calcitriol production and function. One of the main cellular signaling pathways mediating cytokine function is the Janus kinase (JAK)--signal transducer and activator of transcription (STAT) pathway. Here, we used a mouse model (Jak1S645P+/- ) that resembles a constitutive activating mutation of the Jak1/Stat3 signaling pathway in humans, and shows altered mineral metabolism, with higher fibroblast growth factor 23 (FGF23) levels, lower PTH levels, and higher calcitriol levels. The higher calcitriol levels are probably due to extrarenal calcitriol production. Furthermore, systemic Jak1/Stat3 activation led to growth impairment and skeletal alterations. The growth plate in long bones showed decreased chondrocyte proliferation rates and reduced height of terminal chondrocytes. Furthermore, we demonstrate that Jak1 is also involved in bone remodeling early in life. Jak1S645P+/- animals have decreased bone and cortical volume, imbalanced bone remodeling, reduced MAP kinase signaling, and local inflammation. In conclusion, Jak1 plays a major role in bone health probably both, directly and systemically by regulating mineral homeostasis. Understanding the role of this signaling pathway will contribute to a better knowledge in bone growth and in mineral physiology, and to the development of selective Jak inhibitors as osteoprotective agents.

Physician-related predictors of referral for multidisciplinary paediatric obesity management: a population-based study.

BACKGROUND: It is recommended that primary care-based physicians refer children with overweight and obesity to multidisciplinary paediatric obesity management, which can help to improve weight and health. OBJECTIVE: To determine predictors of referral to multidisciplinary paediatric obesity management. METHODS: This retrospective, population-level study included physicians who could refer 2-17 years old with a body mass index ≥85th percentile to one of three multidisciplinary paediatric obesity management clinics in Alberta, Canada. Physician demographic and procedural data were obtained from Practitioner Claims and Provider Registry maintained by Alberta Health from January 2014 to December 2017. Physician characteristics were compared based on whether they did or did not refer children for obesity management. Univariable and multivariable logistic regression models analysed associations between physician characteristics and referral making. RESULTS: Of the 3863 physicians (3468 family physicians, 395 paediatricians; 56% male; 49.3 ± 12.2 years old; 22.3 ± 12.6 years since graduation) practicing during the study period, 1358 (35.2%) referred at least one child for multidisciplinary paediatric obesity management. Multivariable regression revealed that female physicians (versus males) [odds ratio (OR): 1.68, 95% confidence interval (CI): 1.46-1.93; P < 0.0001], paediatricians (versus family physicians) (OR: 4.89, 95% CI: 3.85-6.21; P < 0.0001) and urban-based physicians (versus non-urban-based physicians) (OR: 2.17, 95% CI: 1.79-2.65; P < 0.0001) were more likely to refer children for multidisciplinary paediatric obesity management. CONCLUSIONS: Approximately one-third of family physicians and paediatricians referred children for multidisciplinary paediatric obesity management. Strategies are needed to improve referral practices for managing paediatric obesity, especially among male physicians, family physicians and non-urban-based physicians as they were less likely to refer children.

Paediatric overweight and obesity impact one-third of children in Canada and the USA. It is recommended that physicians refer children with overweight and obesity to paediatric obesity management, which can help to improve their weight and health. While referral practices of US physicians have been well characterized, Canadian evidence remains limited. To address this gap, we examined predictors of referral making for paediatric obesity management. Our study included physicians (family physicians and paediatricians) who could refer 2­17 years old with overweight and obesity to three paediatric weight management clinics in Alberta, Canada between January 2014 and December 2017. Descriptive analyses and regression models were performed. Of the 3863 physicians practicing during the study period, 1358 (35.2%) referred at least one child for paediatric obesity management. Referring physicians were more likely to be female, paediatricians and practicing in urban-based clinics. Additional research is needed to explore physicians' decisions to refer children for obesity management, which can inform interventions to enhance referral, and ultimately, improve the health and well-being of children with obesity.

Systemic Jak1 activation provokes hepatic inflammation and imbalanced FGF23 production and cleavage.

Fibroblast growth factor 23 (FGF23) is a main regulator of mineral homeostasis. Low and high circulating FGF23 levels are associated with bone, renal, cardiovascular diseases, and increased mortality. Understanding the factors and signaling pathways affecting FGF23 levels is crucial for the management of these diseases and their complications. Here, we show that activation of the Jak1/Stat3 signaling pathway leads to inflammation in liver and to an increase in hepatic FGF23 synthesis, a key hormone in mineral metabolism. This increased synthesis leads to massive C-terminal FGF23 circulating levels, the inactive C-terminal fragment, and increased intact FGF23 levels, the active form, resulting in imbalanced production and cleavage. Liver inflammation does not lead to activation of the calcineurin-NFAT pathway, and no signs of systemic inflammation could be observed. Despite the increase of active intact FGF23, excessive C-terminal FGF23 levels block the phosphaturic activity of FGF23. Therefore, kidney function and renal αKlotho expression are normal and no activation of the MAPK pathway was detected. In addition, activation of the Jak1/Stat3 signaling pathway leads to high calcitriol levels and low parathyroid hormone production. Thus, JAK1 is a central regulator of mineral homeostasis. Moreover, this study also shows that in order to assess the impact of high FGF23 levels on disease and kidney function, the source and the balance in FGF23 production and cleavage are critical.

Toxicity of Dithiothreitol (DTT) to Drosophila melanogaster.

The thiol-containing compound Dithiothreitol (DTT) has been shown to be toxic to cultured cells by inducing the generation of reactive oxygen species that ultimately cause cell death. However, its effects on multicellular organisms and the environment have not been investigated yet in detail. In this work, we tested the toxicity of DTT to the model insect Drosophila melanogaster. We show that DTT is lethal to D. melanogaster by topical application but not through feeding. DTT treatment triggers the transcription of the canonical apoptosis regulators grim, hid and rpr at low amounts. The amplitude of this induction declines with elevating DTT amounts. By live microscopy, we observe apoptotic cells especially in the gut of DTT treated flies. In parallel, low DTT amounts also activate the expression of the cuticle barrier component gene snsl. This indicates that a physical defence response is launched upon DTT contact. This combined measure is seemingly successful in preventing fly death. The expression of a number of known detoxification genes including cyp6a2, cyp6a8, cyp12d1 and GstD2 is also enhanced through DTT contact. The degree of upregulation of these genes is proportional to the applied DTT amounts. Despite this effort, flies exposed to high amounts of DTT eventually die. Together, D. melanogaster is able to sense DTT toxicity and adjust the defence response successfully at least at low concentrations. This is the first time to analyse the molecular consequences of DTT exposure in a multicellular organism. Our work provides a new model to discuss the physiological response of animals against thiol toxins and to resurvey the effect of redox agents on the environment.