The value of the CoughAssist® in the daily lives of children with neuromuscular disorders: Experiences of families, children and physiotherapists.

OBJECTIVES: We explored parents', children's and physiotherapists' experiences of regular CoughAssist® use, along with their perceptions of its value as an adjunct to in their daily, home respiratory management. METHODS: All children in the care of a specialist neuromuscular service who regularly used a CoughAssist® device at home participated. Qualitative case study methods involved semi-structured interviews with three children with neuromuscular disorders (NMD), their parents and physiotherapist. Data were analysed using thematic content analysis. RESULTS: Participants (n = 9) perceived the CoughAssist® held benefits for physical, social and emotional aspects of living with NMD. Poor adherence was identified as the major barrier to effective use, governed by factors including child's resistance, time constraints, treatment preference, practitioner support and fear of pressure trauma. CONCLUSIONS: Barriers to regular CoughAssist® use must be identified and individually addressed to enable uptake into respiratory care, accurately measure its effectiveness and realise its perceived benefits to children with NMD.

Targeted prostate cancer screening in BRCA1 and BRCA2 mutation carriers: results from the initial screening round of the IMPACT study.

BACKGROUND: Men with germline breast cancer 1, early onset (BRCA1) or breast cancer 2, early onset (BRCA2) gene mutations have a higher risk of developing prostate cancer (PCa) than noncarriers. IMPACT (Identification of Men with a genetic predisposition to ProstAte Cancer: Targeted screening in BRCA1/2 mutation carriers and controls) is an international consortium of 62 centres in 20 countries evaluating the use of targeted PCa screening in men with BRCA1/2 mutations. OBJECTIVE: To report the first year's screening results for all men at enrollment in the study. DESIGN, SETTING AND PARTICIPANTS: We recruited men aged 40-69 yr with germline BRCA1/2 mutations and a control group of men who have tested negative for a pathogenic BRCA1 or BRCA2 mutation known to be present in their families. All men underwent prostate-specific antigen (PSA) testing at enrollment, and those men with PSA >3 ng/ml were offered prostate biopsy. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: PSA levels, PCa incidence, and tumour characteristics were evaluated. The Fisher exact test was used to compare the number of PCa cases among groups and the differences among disease types. RESULTS AND LIMITATIONS: We recruited 2481 men (791 BRCA1 carriers, 531 BRCA1 controls; 731 BRCA2 carriers, 428 BRCA2 controls). A total of 199 men (8%) presented with PSA >3.0 ng/ml, 162 biopsies were performed, and 59 PCas were diagnosed (18 BRCA1 carriers, 10 BRCA1 controls; 24 BRCA2 carriers, 7 BRCA2 controls); 66% of the tumours were classified as intermediate- or high-risk disease. The positive predictive value (PPV) for biopsy using a PSA threshold of 3.0 ng/ml in BRCA2 mutation carriers was 48%-double the PPV reported in population screening studies. A significant difference in detecting intermediate- or high-risk disease was observed in BRCA2 carriers. Ninety-five percent of the men were white, thus the results cannot be generalised to all ethnic groups. CONCLUSIONS: The IMPACT screening network will be useful for targeted PCa screening studies in men with germline genetic risk variants as they are discovered. These preliminary results support the use of targeted PSA screening based on BRCA genotype and show that this screening yields a high proportion of aggressive disease. PATIENT SUMMARY: In this report, we demonstrate that germline genetic markers can be used to identify men at higher risk of prostate cancer. Targeting screening at these men resulted in the identification of tumours that were more likely to require treatment.

Classification of ambiguous mutations in DNA mismatch repair genes identified in a population-based study of colorectal cancer.

Identification of germline mutations in DNA mismatch repair genes in colorectal cancer probands without an extensive family history can be problematic when ascribing relevance to cancer causation. We undertook a structured assessment of the disease-causing potential of sequence variants identified in a prospective, population-based study of 932 colorectal cancer patients, diagnosed at <55 years of age. Patient samples were screened for germline mutations in MLH1, MSH2, and MSH6. Of 110 carriers, 74 (67%) had one of 33 rare variants of uncertain pathogenicity (12 MLH1, 11 MSH2, and 10 MSH6). Pathogenicity was assessed by determining segregation in families, allele frequency in large numbers of unaffected controls, effect on mRNA for putative splice-site mutations, effect on protein function by bioinformatic analysis and tumor microsatellite instability (MSI) status and DNA mismatch repair protein expression by immunohistochemistry. Because of the ambiguous nature of these variants and lack of concordance between functional assays and control allele frequency, we devised a scoring system to rank the degree of support for a pathogenic role. MLH1 c.200G>A p.G67E, MLH1 c.2041G>A p.A681T, and MSH2 c.2634+5G>C were categorized as pathogenic through assimilation of all available data, while 14 variants were categorized as benign (seven MLH1, three MSH2, and four MSH6). Interestingly, there is tentative evidence suggesting a possible protective effect of three variants (MLH1 c.2066A>G pQ689R, c.2146G>A p.V716M, and MSH2 c.965G>A p.G322D). These findings support a causal link with colorectal cancer for several DNA mismatch repair gene variants. However, the majority of missense changes are likely to be inconsequential polymorphisms.

Formation of high density lipoproteins containing both apolipoprotein A-I and A-II in the rabbit.

Human plasma HDLs are classified on the basis of apolipoprotein composition into those that contain apolipoprotein A-I (apoA-I) without apoA-II [(A-I)HDL] and those containing apoA-I and apoA-II [(A-I/A-II)HDL]. ApoA-I enters the plasma as a component of discoidal particles, which are remodeled into spherical (A-I)HDL by LCAT. ApoA-II is secreted into the plasma either in the lipid-free form or as a component of discoidal high density lipoproteins containing apoA-II without apoA-I [(A-II)HDL]. As discoidal (A-II)HDL are poor substrates for LCAT, they are not converted into spherical (A-II)HDL. This study investigates the fate of apoA-II when it enters the plasma. Lipid-free apoA-II and apoA-II-containing discoidal reconstituted HDL [(A-II)rHDL] were injected intravenously into New Zealand White rabbits, a species that is deficient in apoA-II. In both cases, the apoA-II was rapidly and quantitatively incorporated into spherical (A-I)HDL to form spherical (A-I/A-II)HDL. These particles were comparable in size and composition to the (A-I/A-II)HDL in human plasma. Injection of lipid-free apoA-II and discoidal (A-II)rHDL was also accompanied by triglyceride enrichment of the endogenous (A-I)HDL and VLDL as well as the newly formed (A-I/A-II)HDL. We conclude that, irrespective of the form in which apoA-II enters the plasma, it is rapidly incorporated into spherical HDLs that also contain apoA-I to form (A-I/A-II)HDL.

Apolipoprotein E enhances hepatic lipase-mediated hydrolysis of reconstituted high-density lipoprotein phospholipid and triacylglycerol in an isoform-dependent manner.

This study compares the kinetics of hepatic lipase (HL)-mediated phospholipid and triacylglycerol hydrolysis in spherical, reconstituted high-density lipoproteins (rHDL) that contain either apolipoprotein E2 (apoE2), apoE3, apoE4, or apoA-I as the sole apolipoprotein. HL-mediated phospholipid hydrolysis was assessed by incubating various concentrations of rHDL that contained only cholesteryl esters (CE) in their core, (E2/CE)rHDL, (E3/CE)rHDL, (E4/CE)rHDL, and (A-I/CE)rHDL, with a constant amount of HL. The rate of phospholipid hydrolysis was determined as the formation of nonesterified fatty acid mass. HL-mediated triacylglycerol hydrolysis was assessed in rHDL containing CE, unlabeled triacylglycerol, and [(3)H]triacylglycerol in their core, (E2/TG)rHDL, (E3/TG)rHDL, (E4/TG)rHDL, and (A-I/TG)rHDL. Triacylglycerol hydrolysis was determined as the ratio of (3)H-labeled hydrolysis products to (3)H-labeled unhydrolyzed triacylglycerol. The rates of phospholipid hydrolysis in the (E2/CE)rHDL, (E3/CE)rHDL, and (E4/CE)rHDL were significantly greater than that in the (A-I/CE)rHDL. The rates of triacylglycerol hydrolysis were also greater in the (E2/TG)rHDL, (E3/TG)rHDL, and (E4/TG)rHDL compared to the (A-I/TG)rHDL, although to a lesser degree than observed with phospholipid hydrolysis. Furthermore, the rates of both phospholipid and triacylglycerol hydrolyses were greater in the (E2)rHDL than in either the (E3)rHDL or the (E4)rHDL. These results show that apoE increases the rate of HL-mediated phospholipid and triacylglycerol hydrolysis in rHDL and that this influence is isoform dependent.