Exon identity influences splicing induced by exonic variants and in silico prediction efficacy

BackgroundMinigenes and in silico prediction tools are commonly used to assess the impact on splicing of CFTR variants. Exon skipping is often neglected though it could impact the efficacy of targeted therapies. The aim of the study was to identify exon skipping associated with CFTR variants and to evaluate in silico predictions of seven freely available software.MethodsCFTR basal exon skipping was evaluated on endogenous mRNA extracted from non-CF nasal cells and on two CFTR minigene banks. In silico tools and minigene systems were used to evaluate the impact of CFTR exonic variants on exon skipping.ResultsData showed that out of 65 CFTR variants tested, 26 enhanced exon skipping and that in silico prediction efficacy was of 50%-66%. Some in silico tools presented predictions with a bias towards the occurrence of splicing events while others presented a bias towards the absence of splicing events (non-detection including true negatives and false negatives). Classification of exons depending on their basal exon skipping level increased prediction rates up to 80%.ConclusionThis study indicates that taking basal exon skipping into account could orientate the choice of the in silico tools to improve prediction rates. It also highlights the need to validate effects using in vitro assays or mRNA studies in patients. Eventually, it shows that variant-guided therapy should also target exon skipping associated with variants.     

Acceptability and Feasibility of Geographically Explicit Ecological Momentary Assessment Among Men Who Have Sex with Men

Syphilis among men who have sex with men (MSM) has increased greatly in the past twenty years in the U.S. Geographically explicit ecological momentary assessment (GEMA), in which behaviors are geotagged and contextualized in time and space, may contribute to a greater understanding of transmission risk. The objective was to determine the acceptability and feasibility of GEMA for assessing HIV and syphilis transmission risk behaviors among a sample of MSM. Participants responded to a brief survey five times a day for two weeks. Feasibility was measured by participant recruitment, enrollment, prompts received and answered, geotagged prompts, and technical interference with data collection. Acceptability was measured by ratings of enjoyment and willingness for future participation. Summaries of five behavioral measures from the brief survey were calculated. Among the 83 participants contacted, 67.5% (56) expressed interest, 98% (55) were scheduled, and 81.8% (45) were enrolled. Participants answered 78.3% (2,277) of prompts received and 87.7% (1,998) of answered prompts were geotagged. Overall, 70.5% (31) enjoyed participating and 91.1% (41) were willing to participate in the future. Among prompts answered, missingness was low for five behavioral measures (range 0.2% (4) to 0.7% (16)). Feasibility and acceptability were high and missingness was low on behavioral measures in this MSM study population. Most participants reported that they would participate again. Future work should focus on whether GEMA improves our understanding of syphilis and HIV transmission risk.

     

Bulbectomy Enhances Neurogenesis and Cell Turnover of Primary Olfactory Neurons But Does Not Abolish Carnosine Expression

Primary olfactory neurons located in the olfactory neuroepithelium project to the ipsilateral olfactory bulb and undergo a continuous process of neurogenesis and differentiation. We describe, in the adult rat, the kinetics of proliferation, differentiation and survival of primary olfactory neurons either in the presence or absence of their target, the olfactory bulb. The experimental design included unilateral bulbectomy, coupled with a single bromodeoxyuridine pulse 35 days after surgery. The rate of proliferation and survival of olfactory neurons was then examined by immunohistochemistry for bromodeoxyuridine, and the differentiation status by in situ hybridization for calmodulin messenger RNA in immature and mature olfactory neurons and immunohistochemistry for the dipeptide carnosine in mature olfactory neurons. We show that primary olfactory neurons can synthesize carnosine in the absence of the olfactory bulb. However, the number of carnosine-immunopositive neurons in the absence of their target is dramatically reduced to less than one-fourth, whereas the number of olfactory neurons expressing calmodulin messenger RNA is only slightly reduced. The numeric reduction of camosine-positive neurons in the target-deprived neuroepithelium is correlated with a dramatic reduction in the survival rate of olfactory neurons, since newly generated olfactory neurons are completely lost 35 days after the bromodeoxyuridine pulse. In contrast, in the normal olfactory neuroepithelium almost one-third of newly generated olfactory neurons survive 35 days after the bromodeoxyuridine pulse. On the whole, these data indicate that most of the primary olfactory neurons have a short lifespan but that once they have connected with the olfactory bulb they may persist longer, and suggest that throughout adulthood olfactory neurons are overproduced, differentiate independently from their target, and then undergo a process of target-induced neuronal selection.     

The effects of antiinflammatory steroids on the response of the guinea-pig isolated ileum to acetylcholine,histamine, nicotine, 5-hydroxytryptamine and electrical stimulation

Summary High concentrations of antiinflammatory steroids (2.5–40 g/ml) reversibly inhibited the electrically induced contractions of the guinea-pig isolated ileum. At 40 g/ml they also reversibly inhibited contractions clicited by acetylcholine, histamine, nicotine and 5-hydroxytryptamine. PGE₁ (2.5 ng/ml), PGE₂ (2.5 ng/ml) and PGF₂ (25 ng/ml) antagonized these effects.The inhibition of contractions elicited by direct agonists were less pronounced than those elicited by indirect or partly indirect agonists. The inhibitory effect of steroids may be related to non-specific actions on biological membranes. An overall sensitization of the smooth muscle by PG's may explain their antagonism to inhibition by steroids.     

Iatrogenic Thyrotoxicosis: Causal Circumstances, Pathophysiology, and Principles of Treatment—Review of the Literature

Thyrotoxicosis is the clinical syndrome that results when tissues are exposed to high levels of circulating thyroid hormones. In most instances thyrotoxicosis is due to hyperthyroidism, a term reserved for disorders characterized by overproduction of thyroid hormones by the thyroid gland. Nevertheless, thyrotoxicosis may also result from a variety of conditions other than thyroid hyperfunction. The present report focuses on the etiologies, pathophysiology, and treatment of iatrogenic thyrotoxicosis. Iatrogenic thyrotoxicosis may be caused by (1) subacute thyroiditis (a result of lymphocytic infiltration, cellular injury, trauma, irradiation) with release of preformed hormones into circulation; (2) excessive ingestion of thyroid hormones (“thyrotoxicosis factitia”); (3) iodine-induced hyperthyroidism (radiologic contrast agents, topical antiseptics, other medications). Among these causes of iatrogenic thyrotoxicosis, that induced by the iodine overload and cytotoxicity associated with amiodarone represents a significant challenge. Successful management of amiodarone-induced thyrotoxicosis requires close cooperation between endocrinologists and endocrine surgeons. Surgical treatment may have a leading yet often underestimated role in view of the potential life-threatening severity of this disease, whereas others kinds of iatrogenic thyrotoxicosis are usually treated conservatively.     

How to optimize physicians' communication skills in cancer care: results of a randomized study assessing the usefulness of posttraining consolidation workshops.

PURPOSE: Although there is wide recognition of the usefulness of improving physicians' communication skills, no studies have yet assessed the efficacy of post-training consolidation workshops. This study aims to assess the efficacy of six 3-hour consolidation workshops conducted after a 2.5-day basic training program. METHODS: Physicians, after attending the basic training program, were randomly assigned to consolidation workshops or to a waiting list. Training efficacy was assessed through simulated and actual patient interviews that were audiotaped at baseline and after consolidation workshops for the consolidation-workshop group, and approximately 5 months after the end of basic training for the waiting-list group. Communication skills were assessed according to the Cancer Research Campaign Workshop Evaluation Manual. Patients' perceptions of communication skills improvement were assessed using a 14-item questionnaire. RESULTS: Sixty-three physicians completed the training program. Communication skills improved significantly more in the consolidation-workshop group compared with the waiting-list group. In simulated interviews, group-by-time repeated measures analysis of variance showed a significant increase in open and open directive questions (P =.014) and utterances alerting patients to reality (P =.049), as well as a significant decrease in premature reassurance (P =.042). In actual patient interviews, results revealed a significant increase in acknowledgements (P =.022) and empathic statements (P =.009), in educated guesses (P =.041), and in negotiations (P =.008). Patients interacting with physicians who benefited from consolidation workshops reported higher scores concerning their physicians' understanding of their disease (P =.004). CONCLUSION: Consolidation workshops further improve a communication skills training program's efficacy and facilitate the transfer of acquired skills to clinical practice.