Understanding Rare Disease Experiences Through the Concept of Morally Problematic Situations.

Rare diseases, defined as having a prevalence inferior to 1/2000, are poorly understood scientifically and medically. Appropriate diagnoses and treatments are scarce, adding to the burden of living with chronic medical conditions. The moral significance of rare disease experiences is often overlooked in qualitative studies conducted with adults living with rare diseases. The concept of morally problematic situations arising from pragmatist ethics shows promise in understanding these experiences. The objectives of this study were to (1) acquire an in-depth understanding of morally problematic situations experienced by adults living with rare diseases in the province of Québec and (2) to develop an integrative model of the concept of morally problematic situations. To this end, an online survey targeting this population was developed through a participatory action research project. Respondents provided 90 long testimonies on the most important morally problematic situations they faced, often in healthcare settings. An integrative model was developed based on various qualitative analyses of these testimonies and relevant literature. The integrative model showcases that morally problematic situations have causes (i.e., contextual and relational factors, personal factors, jeopardized valuations), have affective repercussions (i.e., emotions and feelings, internal tensions), prompt action (i.e., through empowerment strategies leading to the evolution of situations), and elicit outcomes (i.e., factual consequences, residual emotions and feelings, positive or negative resolutions). In sum, this study advances understanding of the moral experiences of adults living with rare diseases while proposing a comprehensive conceptual tool to guide future empirical bioethics research on moral experiences.

Cystic fibrosis-related diabetes onset can be predicted using biomarkers measured at birth.

PURPOSE: Cystic fibrosis (CF), caused by pathogenic variants in the CF transmembrane conductance regulator (CFTR), affects multiple organs including the exocrine pancreas, which is a causal contributor to cystic fibrosis-related diabetes (CFRD). Untreated CFRD causes increased CF-related mortality whereas early detection can improve outcomes. METHODS: Using genetic and easily accessible clinical measures available at birth, we constructed a CFRD prediction model using the Canadian CF Gene Modifier Study (CGS; n = 1,958) and validated it in the French CF Gene Modifier Study (FGMS; n = 1,003). We investigated genetic variants shown to associate with CF disease severity across multiple organs in genome-wide association studies. RESULTS: The strongest predictors included sex, CFTR severity score, and several genetic variants including one annotated to PRSS1, which encodes cationic trypsinogen. The final model defined in the CGS shows excellent agreement when validated on the FGMS, and the risk classifier shows slightly better performance at predicting CFRD risk later in life in both studies. CONCLUSION: We demonstrated clinical utility by comparing CFRD prevalence rates between the top 10% of individuals with the highest risk and the bottom 10% with the lowest risk. A web-based application was developed to provide practitioners with patient-specific CFRD risk to guide CFRD monitoring and treatment.

Impact of ENaC downregulation in transgenic mice on the outcomes of acute lung injury induced by bleomycin.

NEW FINDINGS: What is the central question of this study? How does the downregulation of ENaC, the major driving force for alveolar fluid clearance, impact acute lung injury outcomes induced by bleomycin, featuring alveolar damage, as observed during ARDS exudative phase? What is the main finding and its importance? ENaC downregulation in αENaC(-/-)Tg+ mice did not elicit a substantial worsening impact on the main bleomycin outcomes. In ARDS patients, both ENaC alteration and alveolar damage are observed. Thus, novel therapeutic avenues, favouring alveolar integrity restauration, in addition to lung oedema resolution capacity, mainly driven by ENaC, would be essential. ABSTRACT: The exudative phase of acute respiratory distress syndrome (ARDS) is characterized by extended alveolar damage, resulting in accumulation of protein-rich inflammatory oedematous fluid in the alveolar space. Na+ reabsorption through ENaC channels is a major driving force for alveolar fluid clearance (AFC) in physiological and pathological conditions. It has previously been shown that partial αENaC impairment in transgenic (αENaC(-/-)Tg+) mice results in reduced AFC in basal conditions and increased wet/dry ratio after thiourea-induced lung oedema, a model in which the integrity of the alveolar epithelium is preserved. The goal of this study was to further investigate the impact of αENaC downregulation in αENaC(-/-)Tg+ mice using an experimental model of acute lung injury induced by bleomycin. A non-significant trend in enhanced weight loss and mortality rates was observed after the bleomycin challenge in αENaC(-/-)Tg+ compared to wild-type (WT) mice. Bronchoalveolar lavage analyses revealed increased TNFα levels and protein concentrations, as indexes of lung inflammation and alveolar damage, in αENaC(-/-)Tg+ mice, compared to WT, at day 3 post-bleomycin, although a statistical difference was no longer measured at day 7. Differential immune cell counts were similar in WT and αENaC(-/-)Tg+ mice challenged with bleomycin. Moreover, lung weight measurements indicated similar oedema levels in WT mice and in transgenic mice with impaired ENaC channels. Altogether, our data indicated that change in ENaC expression does not elicit a significant impact on lung oedema level/resolution in the bleomycin model, featuring alveolar damage.

Post-Transcriptional Modulation of aENaC mRNA in Alveolar Epithelial Cells: Involvement of its 3' Untranslated Region.

BACKGROUND/AIMS: The epithelial sodium channel (ENaC) expressed in alveolar epithelial cells plays a major role in lung liquid clearance at birth and lung edema resorption in adulthood. We showed previously that αENaC mRNA expression is downregulated in part via posttranscriptional regulation of mRNA stability. In the present work, the role of the αENaC 3' untranslated region (3'UTR) in the regulation of mRNA stability was studied further. METHODS: Quantitative reverse transcription PCR (qRT-PCR) was performed to investigate the expression of αENaC in alveolar epithelial cells. The role of the αENaC 3'UTR was evaluated through sequential deletions. RNA affinity chromatography and mass spectrometry were achieved to investigate the nature of the proteins that could bind this sequence. The function of these proteins was assessed through knockdown and overexpression in vitro. RESULTS: First, we found that αENaC mRNA half-life was much shorter than expected when using a transcriptionally controlled plasmid expression system compared to Actinomycin D treatment. Sequential deletions of the αENaC 3'UTR revealed that the αENaC 3'UTR plays an important role in the modulation of αENaC mRNA stability, and that there is a complex stabilizing and destabilizing interplay between different regions of the 3'UTR that modulate this process. Finally, we identified RNA-binding proteins that interact with the αENaC 3'UTR and showed that Dhx36 and Tial1 are involved in the decrease in αENaC mRNA stability via the proximal region of its 3'UTR. CONCLUSION: Taken together, these findings indicate that the αENaC 3'UTR plays an important role in modulating transcript levels, and Dhx36 and Tial1 seem to be involved in posttranscriptional regulation of αENaC expression in alveolar epithelial cells.

Effect of adrenalectomy on pulmonary edema resolution.

PURPOSE: The capacity of the lung to clear edema fluid has been shown to be one of the factors that can influence the prognosis of cardiogenic and noncardiogenic pulmonary edema. Active Na+ transport across the alveolar epithelium is the main driving force involved in this physiological process. Since endogenous catecholamines are known to activate the sodium-dependent mechanism of alveolar edema clearance, the objective of the present study was to explore if adrenalectomy, which prevents the release of endogenous catecholamines and other hormones, such as corticosterone, into circulation, would affect edema resolution in a model of lung injury induced by thiourea. METHODS: A high-permeability pulmonary edema was induced in adult male Sprague-Dawley rats using a thiourea-induced pulmonary edema model. To determine if the release of adrenalin and corticosterone is essential for resolution of the thiourea-induced edema, we measured 1) the release of adrenalin and corticosterone in urine and 2) edema resolution in control animals and adrenalectomized animals. RESULTS: The administration of thiourea significantly increased the wet-to-dry ratio after four and eight hours. After 12 and 24 hours, the wet-to-dry ratio gradually returned to baseline. Although thiourea-induced pulmonary edema was associated with a significant increase in urine adrenalin and corticosterone, the absence of adrenalin and corticosterone response in adrenalectomized animals did not prevent the resolution of the edema. CONCLUSIONS: These experiments demonstrated that resolution of thioureainduced pulmonary edema can occur in the absence of hormonal secretion by the adrenal glands.

DNA Methylation Regulates RGS2-induced S100A12 Expression in Airway Epithelial Cells.

RGS2 is a key modulator of stress in human airway epithelial cells, especially of hyperresponsiveness and mucin hypersecretion, both of which are features of cystic fibrosis (CF). Because its expression can be modulated through the DNA methylation pathway, we hypothesize that RGS2 is downregulated by DNA hypermethylation in CF airway epithelial cells. This downregulation would then lead to an enhanced inflammatory response. We demonstrated RGS2 transcript and protein downregulation in cultured airway epithelial cells from patients with CF and validated our findings in two CF epithelial cell lines. A methylated DNA immunoprecipitation array showed the presence of methylated cytosine on 13 gene promoters in CF. Among these genes, we confirmed that the RGS2 promoter was hypermethylated by using bisulfite conversion coupled with a methylation-specific PCR assay. Finally, we showed that downregulation of RGS2 in non-CF cells increased the expression of S100A12, a proinflammatory marker. These results highlight the importance of epigenetic regulation in gene expression in CF and show that RGS2 might modulate the inflammatory response in CF through DNA methylation control.

Loss of barrier integrity in alveolar epithelial cells downregulates ENaC expression and activity via Ca2+ and TRPV4 activation.

The epithelial Na channel (ENaC) plays an essential role in lung physiology by modulating the amount of liquid lining the respiratory epithelium. Here, we tested the effect of breaking alveolar epithelial cell barrier integrity on ENaC expression and function. We found that either mechanical wounding by scratching the monolayer or disruption of tight junction with EDTA induced a ~ 50% decrease of α,ß and γENaC mRNA expression and an 80% reduction of ENaC short-circuit current (Isc) at 6 h. Scratching the cell monolayer generated a Ca2+ wave that spread from the margin of the scratch to distant cells. Pretreatment with BAPTA-AM, an intracellular Ca2+ chelator, abolished the effect of mechanical wounding and EDTA on αENaC mRNA expression, suggesting that [Ca2+]i is important for this modulation. We tested the hypothesis that a mechanosensitive channel such as TRPV4, a cationic channel known to increase [Ca2+]i, could mediate this effect. Activation of the channel with the TRPV4 specific agonist GSK-1016790A (GSK) decreased αENAC mRNA expression and almost completely abolished ENaC Isc. Pretreatment of alveolar epithelial cells with HC-067047 (HC0), a specific TRPV4 antagonist, reduced the extent of αENAC mRNA downregulation by mechanical wounding and EDTA. Altogether, our results suggest that mechanical stress induced by wounding or TRPV4-mediated loss of tight junction increases [Ca2+]i and elicits a Ca2+ wave that affects ENaC expression and function away from the site of injury. These data are important to better understand how Ca2+ signaling affects lung liquid clearance in injured lungs.

A clinical tool to calculate post-transplant survival using pre-transplant clinical characteristics in adults with cystic fibrosis.

BACKGROUND: We previously identified factors associated with a greater risk of death post-transplant. The purpose of this study was to develop a clinical tool to estimate the risk of death after transplant based on pre-transplant variables. METHODS: We utilized the Canadian CF registry to develop a nomogram that incorporates pre-transplant clinical measures to assess post-lung transplant survival. The 1-, 3-, and 5-year survival estimates were calculated using Cox proportional hazards models. RESULTS: Between 1988 and 2012, 539 adult Canadians with CF received a lung transplant with 208 deaths in the study period. Four pre-transplant factors most predictive of poor post-transplant survival were older age at transplantation, infection with B. cepacia complex, low FEV1 percent predicted, and pancreatic sufficiency. A nonlinear relationship was found between risk of death and FEV1 percent predicted, age at transplant, and BMI. We constructed a risk calculator based on our model to estimate the 1-, 3-, and 5-year probability of survival after transplant which is available online. CONCLUSIONS: Our risk calculator quantifies the risk of death associated with lung transplant using pre-transplant factors. This tool could aid clinicians and patients in the decision-making process and provide information regarding the timing of lung transplantation.

Proprotein Convertase Subtilisin/Kexin type 9 affects insulin but not lipid metabolism in cystic fibrosis.

PURPOSE: Cystic Fibrosis (CF) is the most common genetic disorder and, with improved survival, glucose abnormalities have emerged as a major comorbidity. Proprotein convertase subtilisin/kexin type 9 (PCSK9), a regulator of plasma LDL-cholesterol homeostasis, is associated with lipid and glucose metabolism in healthy individuals. Here we report on the link between PCSK9 and markers of metabolism in CF. METHODS: Cross-sectional analysis was performed on CF patients (≥ 18 years, N=94) from the Montreal Cohort, without known diabetes, and on healthy individuals (N=19). The levels of PCSK9 and lipid markers were quantified and all subjects underwent a 2 h oral glucose tolerance test. RESULTS: No significant differences in PCSK9 levels were found between healthy individuals and patients with CF, or between the groups with different degrees of glucose tolerance. No association was found between PCSK9 and markers of lipid metabolism; however, a positive correlation was found between PCSK9 and total insulin secretion and a negative one with insulin sensitivity in CF patients who had normal glucose tolerance. CONCLUSION: Circulating levels of PCSK9 in the CF population are comparable to those in the healthy population. There are no associations between PCSK9 levels and either glucose or lipid homeostasis parameters. Nevertheless, a statistically significant link was observed between PCSK9 and markers of insulin homeostasis, solely in CF patients who presented normal glucose tolerance. Further exploration of the relationship between PCSK9 and insulin homeostasis in CF patients with normal glucose tolerance is warranted.

Real-time imaging of inflation-induced ATP release in the ex vivo rat lung.

Extracellular ATP and other nucleotides are important autocrine/paracrine mediators that regulate diverse processes critical for lung function, including mucociliary clearance, surfactant secretion, and local blood flow. Cellular ATP release is mechanosensitive; however, the impact of physical stimuli on ATP release during breathing has never been tested in intact lungs in real time and remains elusive. In this pilot study, we investigated inflation-induced ATP release in rat lungs ex vivo by real-time luciferin-luciferase (LL) bioluminescence imaging coupled with simultaneous infrared tissue imaging to identify ATP-releasing sites. With LL solution introduced into air spaces, brief inflation of such edematous lung (1 s, ∼20 cmH2O) induced transient (<30 s) ATP release in a limited number of air-inflated alveolar sacs during their recruitment/opening. Released ATP reached concentrations of ∼10-6 M, relevant for autocrine/paracrine signaling, but it remained spatially restricted to single alveolar sacs or their clusters. ATP release was stimulus dependent: prolonged (100 s) inflation evoked long-lasting ATP release that terminated upon alveoli deflation/derecruitment while cyclic inflation/suction produced cyclic ATP release. With LL introduced into blood vessels, inflation induced transient ATP release in many small patchlike areas the size of alveolar sacs. Findings suggest that inflation induces ATP release in both alveoli and the surrounding blood capillary network; the functional units of ATP release presumably consist of alveolar sacs or their clusters. Our study demonstrates the feasibility of real-time ATP release imaging in ex vivo lungs and provides the first direct evidence of inflation-induced ATP release in lung air spaces and in pulmonary blood capillaries, highlighting the importance of purinergic signaling in lung function.

CFTR silencing in pancreatic ß-cells reveals a functional impact on glucose-stimulated insulin secretion and oxidative stress response.

Cystic fibrosis (CF)-related diabetes (CFRD) has become a critical complication that seriously affects the clinical outcomes of CF patients. Although CFRD has emerged as the most common nonpulmonary complication of CF, little is known about its etiopathogenesis. Additionally, whether oxidative stress (OxS), a common feature of CF and diabetes, influences CFRD pathophysiology requires clarification. The main objective of this study was to shed light on the role of the cystic fibrosis transmembrane conductance regulator (CFTR) in combination with OxS in insulin secretion from pancreatic ß-cells. CFTR silencing was accomplished in MIN6 cells by stable expression of small hairpin RNAs (shRNA), and glucose-induced insulin secretion was evaluated in the presence and absence of the valuable prooxidant system iron/ascorbate (Fe/Asc; 0.075/0.75 mM) along with or without the antioxidant Trolox (1 mM). Insulin output from CFTR-silenced MIN6 cells was significantly reduced (∼ 70%) at basal and at different glucose concentrations compared with control Mock cells. Furthermore, CFTR silencing rendered MIN6 cells more sensitive to OxS as evidenced by both increased lipid peroxides and weakened antioxidant defense, especially following incubation with Fe/Asc. The decreased insulin secretion in CFTR-silenced MIN6 cells was associated with high levels of NF-κB (the major participant in inflammatory responses), raised apoptosis, and diminished ATP production in response to the Fe/Asc challenge. However, these defects were alleviated by the addition of Trolox, thereby pointing out the role of OxS in aggravating the effects of CFTR deficiency. Our findings indicate that CFTR deficiency in combination with OxS may contribute to endocrine cell dysfunction and insulin secretion, which at least in part may explain the development of CFRD.

A contemporary survival analysis of individuals with cystic fibrosis: a cohort study.

Previously established predictors of survival may no longer apply in the current era of cystic fibrosis (CF) care. Our objective was to identify risk factors associated with survival in a contemporary CF population. We used the Canadian CF Registry, a population-based cohort, to calculate median age of survival and summarise patient characteristics from 1990 to 2012. Clinical, demographic and geographical factors, and survival were estimated for a contemporary cohort (2000-2012) using Cox proportional hazards models. There were 5787 individuals in the registry between 1990 and 2012. Median survival age increased from 31.9 years (95% CI 28.3-35.2 years) in 1990 to 49.7 years (95% CI 46.1-52.2 years) in the most current 5-year window ending in 2012. Median forced expiratory volume in 1 s improved (p=0.04) and fewer subjects were malnourished (p<0.001) over time. Malnourished patients (hazard ratio (HR) 2.1, 95% CI 1.6-2.8), those with multiple exacerbations (HR 4.5, 95% CI 3.2-6.4) and women with CF-related diabetes (HR 1.8, 95% CI 1.2-2.7) were at increased risk of death. Life expectancy in Canadians with CF is increasing. Modifiable risk factors such as malnutrition and pulmonary exacerbations are associated with an increased risk of death. The sex gap in CF survival may be explained by an increased hazard for death in women with CF-related diabetes.

Association between serum YKL-40 level and dysglycemia in cystic fibrosis.

BACKGROUND: YKL-40, a chitinase-like protein, is a biomarker for type 1 and type 2 diabetes prognosis. We hypothesized that YKL-40 protein levels are elevated in CF patients with dysglycemia. METHODS: Seventeen healthy control subjects and 66 CF patients were prospectively recruited and subjected to an oral glucose tolerance test. In all participants, fasting serum YKL-40 was compared between control and CF patients and between normal glucose-tolerant patients (NG-CF) and CF patients with dysglycemia (DG-CF). A Botnia clamp procedure was performed on a subset of patients for each group to determine the impact of acute increases of either glucose or insulin on YKL-40 concentration. RESULTS: CF patients had higher serum YKL-40 values than the controls (113 [49;288] vs. 38 [30;50] ng/ml, p<0.001). YKL-40 concentrations in CF patients were mainly increased in the DG-CF group, who had significantly higher values: 213 [93;383] vs. 67 [27;97] ng/ml in the NG-CF group, p<0.001). No significant modulation of YKL-40 concentration was observed in serum of CF (NG or DG-CF) or non-CF patients, after acute exposure to glucose or insulin. CONCLUSIONS: Higher serum YKL-40 levels in CF patients are significantly associated with dysglycemia. The increase in YKL-40 is potentially associated with an inflammatory response resulting from chronic glucose intolerance or CF disease evolution.

Oxidative stress modulates the expression of genes involved in cell survival in ΔF508 cystic fibrosis airway epithelial cells.

Although cystic fibrosis (CF) pathophysiology is explained by a defect in CF transmembrane conductance regulator (CFTR) protein, the broad spectrum of disease severity is the consequence of environmental and genetic factors. Among them, oxidative stress has been demonstrated to play an important role in the evolution of this disease, with susceptibility to oxidative damage, decline of pulmonary function, and impaired lung antioxidant defense. Although oxidative stress has been implicated in the regulation of inflammation, its molecular outcomes in CF cells remain to be evaluated. To address the question, we compared the gene expression profile in NuLi-1 cells with wild-type CFTR and CuFi-1 cells homozygous for ΔF508 mutation cultured at air-liquid interface. We analyzed the transcriptomic response of these cell lines with microarray technology, under basal culture conditions and after 24 h oxidative stress induced by 15 µM 2,3-dimethoxy-1,4-naphtoquinone. In the absence of oxidative conditions, CuFi-1 gene profiling showed typical dysregulated inflammatory responses compared with NuLi-1. In the presence of oxidative conditions, the transcriptome of CuFi-1 cells reflected apoptotic transcript modulation. These results were confirmed in the CFBE41o- and corrCFBE41o- cell lines as well as in primary culture of human CF airway epithelial cells. Altogether, our data point to the influence of oxidative stress on cell survival functions in CF and identify several genes that could be implicated in the inflammation response observed in CF patients.

K+ channels regulate ENaC expression via changes in promoter activity and control fluid clearance in alveolar epithelial cells.

Active Na+ absorption by alveolar ENaC is the main driving force of liquid clearance at birth and lung edema resorption in adulthood. We have demonstrated previously that long-term modulation of KvLQT1 and KATP K+ channel activities exerts sustained control in Na+ transport through the regulation of ENaC expression in primary alveolar type II (ATII) cells. The goal of the present study was: 1) to investigate the role of the alpha-ENaC promoter, transfected in the A549 alveolar cell line, in the regulation of ENaC expression by K+ channels, and 2) to determine the physiological impact of K+ channels and ENaC modulation on fluid clearance in ATII cells. KvLQT1 and KATP channels were first identified in A549 cells by PCR and Western blotting. We showed, for the first time, that KvLQT1 activation by R-L3 (applied for 24 h) increased alpha-ENaC expression, similarly to KATP activation by pinacidil. Conversely, pharmacological KvLQT1 and KATP inhibition or silencing with siRNAs down-regulated alpha-ENaC expression. Furthermore, K+ channel blockers significantly decreased alpha-ENaC promoter activity. Our results indicated that this decrease in promoter activity could be mediated, at least in part, by the repressor activity of ERK1/2. Conversely, KvLQT1 and KATP activation dose-dependently enhanced alpha-ENaC promoter activity. Finally, we noted a physiological impact of changes in K+ channel functions on ERK activity, alpha-, beta-, gamma-ENaC subunit expression and fluid absorption through polarized ATII cells. In summary, our results disclose that K+ channels regulate alpha-ENaC expression by controlling its promoter activity and thus affect the alveolar function of fluid clearance.

Cycloheximide and lipopolysaccharide downregulate αENaC mRNA via different mechanisms in alveolar epithelial cells.

Active Na(+) transport mediated by epithelial Na(+) channel (ENaC) is vital for fetal lung fluid reabsorption at birth and pulmonary edema resolution. Previously, we demonstrated that αENaC expression and activity are downregulated in alveolar epithelial cells by cycloheximide (Chx) and Pseudomonas aeruginosa. The regulatory mechanisms of αENaC mRNA expression by Chx and lipopolysaccharide (LPS) from P. aeruginosa were further studied in the present work. Both agents decreased αENaC mRNA expression to 50% of control values after 4 h. Chx repressed αENaC expression in a dose-dependent manner independently of protein synthesis. Although extracellular signal-regulated kinases 1 and 2 (ERK1/2) and p38 mitogen-activated protein kinase (MAPK) pathways were activated by the two treatments, their mechanisms of ENaC mRNA modulation were different. First, activation of the signaling pathways was sustained by Chx but only transiently by LPS. Second, ERK1/2 or p38 MAPK inhibition attenuated the effects of Chx on αENaC mRNA, whereas suppression of both signaling pathways was necessary to alleviate the outcome of LPS on αENaC mRNA. The molecular mechanisms involved in the decrease of αENaC expression were investigated in both conditions. LPS, but not Chx, significantly reduced αENaC promoter activity via the ERK1/2 and p38 MAPK pathways. These results suggest that LPS attenuates αENaC mRNA expression via diminution of transcription, whereas Chx could trigger some posttranscriptional mechanisms. Although LPS and Chx downregulate αENaC mRNA expression similarly and with similar signaling pathways, the mechanisms modulating ENaC expression are different depending on the nature of the cellular stress.

Induction of nitric oxide synthase expression by lipopolysaccharide is mediated by calcium-dependent PKCα-ß1 in alveolar epithelial cells.

Nitric oxide (NO) plays an important role in innate host defense and inflammation. In response to infection, NO is generated by inducible nitric oxide synthase (iNOS), a gene product whose expression is highly modulated by different stimuli, including lipopolysaccharide (LPS) from gram-negative bacteria. We reported recently that LPS from Pseudomonas aeruginosa altered Na⁺ transport in alveolar epithelial cells via a suramin-dependent process, indicating that LPS activated a purinergic response in these cells. To further study this question, in the present work, we tested whether iNOS mRNA and protein expression were modulated in response to LPS in alveolar epithelial cells. We found that LPS induced a 12-fold increase in iNOS mRNA expression via a transcription-dependent process in these cells. iNOS protein, NO, and nitrotyrosine were also significantly elevated in LPS-treated cells. Ca²âº chelation and protein kinase C (PKCα-ß1) inhibition suppressed iNOS mRNA induction by LPS, implicating Ca²âº-dependent PKC signaling in this process. LPS evoked a significant increase of extracellular ATP. Because PKC activation is one of the signaling pathways known to mediate purinergic signaling, we evaluated the hypothesis that iNOS induction was ATP dependent. Although high suramin concentration inhibited iNOS mRNA induction, the process was not ATP dependent, since specific purinergic receptor antagonists could not inhibit the process. Altogether, these findings demonstrate that iNOS expression is highly modulated in alveolar epithelial cells by LPS via a Ca²âº/PKCα-ß1 pathway independent of ATP signaling.

Morally Problematic Situations Encountered by Adults Living With Rare Diseases.

BACKGROUND: Rare diseases are generally poorly understood from scientific and medical standpoints due, to their complexity and low prevalence. As a result, individuals living with rare diseases struggle to obtain timely diagnoses and suitable care. These clinical difficulties add to the physical and psychological impacts of living with chronic and often severe medical conditions. From the standpoint of pragmatist ethics, the morally problematic situations that adults living with rare diseases experience matter crucially. However, there is little known about these experiences. METHODS: A survey study was conducted with 121 adults living with rare diseases in Québec, Canada, to identify morally problematic situations encountered in the healthcare system and everyday life as part of a participatory action research project. Morally problematic situations elicited internal tensions and constraints to agency. RESULTS: Adults living with rare diseases experienced morally problematic situations of stigmatization, disbelief, and sometimes abuse in the healthcare system. These situations were compounded by diagnostic delays, inadequate care, and suboptimal follow-up, and led some individuals to opt-out of medical care. In their personal lives, these individuals sometimes found themselves in situations of physical and financial dependency. They often also had to give up professional occupations, academic training, or life projects. CONCLUSIONS: Adults living with rare diseases experience important morally problematic situations navigating the healthcare system and their everyday lives, some of which could be alleviated through interventions developed through future participatory action research.

An Ethics Action Plan for Rare Disease Care: Participatory Action Research Approach.

BACKGROUND: Owing to their low prevalence, rare diseases are poorly addressed in the scientific literature and clinical practice guidelines. Thus, health care workers are inadequately equipped to provide timely diagnoses, appropriate treatment, and support for these poorly understood conditions. These clinical tribulations are experienced as moral challenges by patients, jeopardizing their life trajectories, dreams, and aspirations. OBJECTIVE: This paper presents an ethical action plan for rare disease care and the process underlying its development. METHODS: This action plan was designed through an ethical inquiry conducted by the Ethics and Rare Diseases Working Group, which included 3 patient partners, 2 clinician researchers, and 1 representative from Québec's rare disease association. RESULTS: The plan is structured into 4 components. Component A presents the key moral challenges encountered by patients, which are the lack of knowledge on rare diseases among health care workers, the problematic attitudes that it sometimes elicits, and the distress and powerlessness experienced by patients. Component B emphasizes a vision for patient partnership in rare disease care characterized by open-mindedness, empathy, respect, and support of patient autonomy from health care workers. Component C outlines 2 courses of action prompted by this vision: raising awareness among health care workers and empowering patients to better navigate their care. Component D compares several interventions that could help integrate these 2 courses of action in rare disease care. CONCLUSIONS: Overall, this action plan represents a toolbox that provides a review of multiple possible interventions for policy makers, hospital managers, practitioners, researchers, and patient associations to critically reflect on key moral challenges experienced by patients with rare diseases and ways to mitigate them. This paper also prompts reflection on the values underlying rare disease care, patient experiences, and health care workers' beliefs and behaviors. Health care workers and patients were the primary beneficiaries of this action plan.