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Effect of smoking status on lung function, patient-reported outcomes, and safety among COPD patients treated with glycopyrrolate inhalation powder: pooled analysis of GEM1 and GEM2 studies.
BackgroundSmoking is a major risk factor for COPD and may impact the efficacy of COPD treatments; however, a large proportion of COPD patients continue to smoke following diagnosis.MethodsThis post-hoc analysis of pooled data from the replicate 12-week, placebo-controlled GEM1 and GEM2 studies assessed the impact of smoking status on the efficacy and safety of glycopyrrolate 15.6 μg twice daily vs placebo in patients with moderate-to-severe COPD. Data from 867 patients enrolled in GEM1 and GEM2 were pooled for analysis and grouped by smoking status (57% current smokers, 43% ex-smokers). Forced expiratory volume in 1 s (FEV1) area under the curve from 0 to 12 h, trough FEV1, forced vital capacity, St George's Respiratory Questionnaire (SGRQ) total score, COPD assessment test (CAT) score, transition dyspnea index (TDI) focal score, daily symptom scores, and rescue medication use were assessed in current smokers and ex-smokers. Incidences of adverse events (AEs) and serious AEs (SAEs) were also assessed.ResultsTreatment with glycopyrrolate resulted in significant improvements in all lung function measures, independent of smoking status. In both current and ex-smokers, changes from baseline in trough FEV1 were less marked in patients taking inhaled corticosteroids (ICS) than those not receiving ICS. Changes from baseline in SGRQ total score and rescue medication use were significantly greater with glycopyrrolate compared with placebo, regardless of smoking status. Changes in the CAT score, TDI focal score, and daily symptom scores significantly improved versus placebo, but only in current smokers. Improvements in patient-reported outcomes (PROs) with glycopyrrolate relative to placebo were numerically greater in current smokers than ex-smokers. The incidences of AEs and SAEs were similar regardless of smoking status.ConclusionsIn this post-hoc analysis of GEM1 and GEM2, glycopyrrolate use led to significant improvements in lung function, independent of baseline smoking status; improvements were less marked among patients receiving background ICS, regardless of baseline smoking status. Improvements in PROs were greater with glycopyrrolate than placebo, and the magnitude of changes was numerically greater among current smokers. The safety profile of glycopyrrolate was comparable between current smokers and ex-smokers
HIGH YIELD IRRIGATED CORN: IMPLEMENTING RESEARCH AND ADAPTING FOR PROFITABLE PRODUCTION
ABSTRACT Irrigated corn producers on the High Plains are frequently confronted with issues that affect the profitability of their operations. The rapid adoption of new methods and technologies that preserve profitability is important for the economic sustainability of High Plains farmers. Traditional research is one method of identifying best management practices that may improve grower productivity and profitability. However, dissemination and implementation of research across broad geographies can be challenging. The scientific method often precludes investigation across a diverse set of variables common within and across farms. Private industry can augment implementation of scientific methods identified as profitable best management practices by employing resources necessary for wide scale spatial and temporal demonstrations. Furthermore, these investigations can be instrumental in prompt identification of processes and practices that improve producer efficiencies and/or profitability. The work and investigations summarized in this paper will demonstrate the use of spatial and temporal observations to identify best management practices for multiple nitrogen (N) applications through corn development. Also, the extension of university research on P and K starter fertilizer and its adoption and implementation by growers will be discussed
Link between foot pain severity and prevalence of depressive symptoms
OBJECTIVE: Associations between pain and depression are well known, yet foot pain, common in populations, has been understudied. This cross-sectional study examined foot pain and severity of foot pain with depressive symptoms in adults. METHODS: Framingham Foot Study (2002-2008) participants completed questionnaires that included questions about foot pain (yes/no; none, mild, moderate, or severe pain) and the Center for Epidemiologic Studies Depression Scale (scores ≥16 indicated depressive symptoms). Age and body mass index (BMI) were also assessed. Sex-specific logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (95% CIs) for associations of foot pain with depressive symptoms, adjusting for age and BMI. In a subset, further models adjusted for leg pain, back pain, or other joint pain. RESULTS: Of 1,464 men and 1,857 women, the mean ± SD age was 66 ± 10 years. Depressive symptoms were reported in 21% of men and 27% of women. Compared to those with no foot pain and independent of age and BMI, both men and women with moderate foot pain had approximately a 2-fold increased odds of depressive symptoms (men with severe foot pain OR of 4 [95% CI 2.26-8.48], women with severe foot pain OR of 3 [95% CI 2.02-4.68]). Considering other pain regions attenuated ORs, but the pattern of results remained unchanged. CONCLUSION: Even after we adjusted for age, BMI, and other regions of pain, those reporting worse foot pain were more likely to report depressive symptoms. These findings suggest that foot pain may be a part of a broader pain spectrum, with an impact beyond localized pain and discomfort
Evaluation of CFTR mRNA stability and dosage
Cystic fibrosis (CF) is an autosomal recessive disorder caused by more than 2000 variants in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. CFTR modulators have completely revolutionized the treatment of CF, with over 90% of individuals with CF being eligible for treatment. However, nonsense variants in CFTR have presented a particular challenge for therapeutic treatment. Nonsense mediated mRNA decay (NMD) targets premature termination codon (PTC)-bearing transcripts to reduce the potentially damaging effects of truncated proteins. CFTR modulators specifically target CFTR to aid in protein processing and function. Since NMD results in absence of CFTR protein, this prevents modulators from restoring CFTR function. mRNA stability is a critical consideration when evaluating therapeutic strategies for CF. In Chapter 2 of my thesis work, I investigate mRNA stability for the sixth most common CF- causing mutation, W1282X. I establish that this variant generates a PTC, targeting the transcript for degradation by NMD and resulting in low levels of steady state mRNA. This finding suggests that W1282X-bearing transcripts will not generate any protein, explaining the lack of CFTR functional response to modulators. In Chapter 3, I investigated several nonsense variants within the N- terminal region of CFTR and show that downstream translation initiation at M265 allows these variants to escape NMD. Treatment of the variant L88X with readthrough compounds combined with CFTR modulators restores full-length, functional CFTR protein. This work indicates that N-terminal variants that evade NMD are ideal candidates for combination treatment of readthrough compounds and modulator therapy. In Chapter 4, I establish a cell-based model system that enables independent expression of two copies of CFTR, which will aid in assessment of rare variants that are difficult to obtain through primary cell collection. Additionally, this system enables us to assess the fitness of the predicted model that each CFTR gene contributes to total CFTR function in an additive manner
Downstream Alternate Start Site Allows N-Terminal Nonsense Variants to Escape NMD and Results in Functional Recovery by Readthrough and Modulator Combination
Genetic variants that introduce premature termination codons (PTCs) have remained difficult to therapeutically target due to lack of protein product. Nonsense mediated mRNA decay (NMD) targets PTC-bearing transcripts to reduce the potentially damaging effects of truncated proteins. Readthrough compounds have been tested on PTC-generating variants in attempt to permit translation through a premature stop. However, readthrough compounds have not proved efficacious in a clinical setting due to lack of stable mRNA. Here, we investigate N-terminal variants in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, which have been shown to escape NMD, potentially through a mechanism of alternative translation initiation at downstream AUG codons. We hypothesized that N-terminal variants in CFTR that evade NMD will produce stable transcript, allowing CFTR function to be restored by a combination of readthrough and protein modulator therapy. We investigate this using two cell line models expressing CFTR-expression minigenes (EMG; HEK293s and CFBEs) and primary human nasal epithelial (NE) cells, and we test readthrough compounds G418 and ELX-02 in combination with CFTR protein modulators. HEK293 cells expressing the variants E60X and L88X generate CFTR-specific core glycosylated products that are consistent with downstream translation initiation. Mutation of downstream methionines at codons 150 and 152 does not result in changes in CFTR protein processing in cells expressing L88X-CFTR-EMG. However, mutation of methionine at 265 results in loss of detectable CFTR protein in cells expressing E60X, L88X, and Y122X CFTR-EMGs, indicating that downstream translation initiation is occurring at the AUG codon at position M265. In HEK293 stable cells harboring L88X, treatment with readthrough compounds alone allows for formation of full-length, but misfolded CFTR protein. Upon addition of protein modulators in combination with readthrough, we observe formation of mature, complex-glycosylated CFTR. In CFBE and NE cells, addition of readthrough ELX-02 and modulator therapy results in substantial recovery of CFTR function. Our work indicates that N-terminal variants generate stable CFTR transcript due to translation initiation at a downstream AUG codon. Thus, individuals with CF bearing 5′ nonsense variants that evade NMD are ideal candidates for treatment with clinically safe readthrough compounds and modulator therapy
Protospacer modification improves base editing of a canonical splice site variant and recovery of CFTR function in human airway epithelial cells
Canonical splice site variants affecting the 5′ GT and 3′ AG nucleotides of introns result in severe missplicing and account for about 10% of disease-causing genomic alterations. Treatment of such variants has proven challenging due to the unstable mRNA or protein isoforms that typically result from disruption of these sites. Here, we investigate CRISPR-Cas9-mediated adenine base editing for such variants in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. We validate a CFTR expression minigene (EMG) system for testing base editing designs for two different targets. We then use the EMG system to test non-standard single-guide RNAs with either shortened or lengthened protospacers to correct the most common cystic fibrosis-causing variant in individuals of African descent (c.2988+1G>A). Varying the spacer region length allowed placement of the editing window in a more efficient context and enabled use of alternate protospacer adjacent motifs. Using these modifications, we restored clinically significant levels of CFTR function to human airway epithelial cells from two donors bearing the c.2988+1G>A variant
Evaluation of both exonic and intronic variants for effects on RNA splicing allows for accurate assessment of the effectiveness of precision therapies.
Elucidating the functional consequence of molecular defects underlying genetic diseases enables appropriate design of therapeutic options. Treatment of cystic fibrosis (CF) is an exemplar of this paradigm as the development of CFTR modulator therapies has allowed for targeted and effective treatment of individuals harboring specific genetic variants. However, the mechanism of these drugs limits effectiveness to particular classes of variants that allow production of CFTR protein. Thus, assessment of the molecular mechanism of individual variants is imperative for proper assignment of these precision therapies. This is particularly important when considering variants that affect pre-mRNA splicing, thus limiting success of the existing protein-targeted therapies. Variants affecting splicing can occur throughout exons and introns and the complexity of the process of splicing lends itself to a variety of outcomes, both at the RNA and protein levels, further complicating assessment of disease liability and modulator response. To investigate the scope of this challenge, we evaluated splicing and downstream effects of 52 naturally occurring CFTR variants (exonic = 15, intronic = 37). Expression of constructs containing select CFTR intronic sequences and complete CFTR exonic sequences in cell line models allowed for assessment of RNA and protein-level effects on an allele by allele basis. Characterization of primary nasal epithelial cells obtained from individuals harboring splice variants corroborated in vitro data. Notably, we identified exonic variants that result in complete missplicing and thus a lack of modulator response (e.g. c.2908G>A, c.523A>G), as well as intronic variants that respond to modulators due to the presence of residual normally spliced transcript (e.g. c.4242+2T>C, c.3717+40A>G). Overall, our data reveals diverse molecular outcomes amongst both exonic and intronic variants emphasizing the need to delineate RNA, protein, and functional effects of each variant in order to accurately assign precision therapies