Assessing polygenic risk score models for applications in populations with under-represented genomics data: an example of Vietnam.

Most polygenic risk score (PRS)models have been based on data from populations of European origins (accounting for the majority of the large genomics datasets, e.g. >78% in the UK Biobank and >85% in the GTEx project). Although several large-scale Asian biobanks were initiated (e.g. Japanese, Korean, Han Chinese biobanks), most other Asian countries have little or near-zero genomics data. To implement PRS models for under-represented populations, we explored transfer learning approaches, assuming that information from existing large datasets can compensate for the small sample size that can be feasibly obtained in developing countries, like Vietnam. Here, we benchmark 13 common PRS methods in meta-population strategy (combining individual genotype data from multiple populations) and multi-population strategy (combining summary statistics from multiple populations). Our results highlight the complementarity of different populations and the choice of methods should depend on the target population. Based on these results, we discussed a set of guidelines to help users select the best method for their datasets. We developed a robust and comprehensive software to allow for benchmarking comparisons between methods and proposed a computational framework for improving PRS performance in a dataset with a small sample size. This work is expected to inform the development of genomics applications in under-represented populations. PRSUP framework is available at: https://github.com/BiomedicalMachineLearning/VGP.

Functional reserve and contractile phenotype of atrial myocardium from patients with atrial remodeling without and with atrial fibrillation.

Atrial contractility and functional reserve in atrial remodeling (AR) without (AR/-AF) or with atrial fibrillation (AR/+AF) are not well characterized. In this study, functional measurements were performed in right atrial muscle strips (n = 71) obtained from patients (N = 22) undergoing routine cardiac surgery with either no AR [left atrial (LA) diameter < 40 mm and no history of AF (hAF)], AR/-AF (LA diameter ≥ 40 mm, no hAF), or AR/+AF (hAF and LA diameter ≥ 40 mm or LAEF < 45%). AR/-AF and AR/+AF were associated with a prolongation of half-time-to-peak (HTTP, P < 0.001) and time-to-peak (TTP) contraction (P < 0.01) when compared with no AR. This effect was seen at baseline and during ß-adrenergic stimulation with isoproterenol (Iso). Early relaxation assessed by half-relaxation time (HRT) was prolonged in AR/-AF (P = 0.03) but not in AR/+AF when compared with no AR at baseline, but this delay in relaxation in AR/-AF was attenuated with Iso. Late relaxation (τ) did not differ between AR/-AF and no AR but was consistently shorter in AR/+AF than no AR before (P = 0.04) and during Iso (P = 0.01), indicating accelerated late relaxation in AR/+AF. Relative force increase during Iso was higher (P = 0.01) and more dispersed (P = 0.047) in patients with AR/+AF. Relative adrenergic response was unaltered in the myocardium of patients with AR/-AF and AR/+AF. In conclusion, AR/-AF and AR/+AF are associated with changes in myocardial inotropic reserve and contractility. The changes are particularly pronounced in patients with AR/+AF, suggesting that the progression from AR/-AF to AR/+AF is associated with progressive alterations in atrial function that may contribute to arrhythmogenesis.NEW & NOTEWORTHY Mechanical alterations in atrial remodeling without (AR/-AF) and with atrial fibrillation (AR/+AF) have not been studied in detail in human atrial tissue preparations. To our knowledge, this is the first study to compare the mechanical phenotype and inotropic reserve in human atrial myocardial preparations from patients with no atrial remodeling, AR/-AF, and AR/+AF. We identify specific patterns of contractile dysfunction and heterogeneity for both, AR/-AF and AR/+AF, indicating the progression of atrial disease.

To disclose or to falsify: The effects of cognitive trust and affective trust on customer cooperation in contact tracing.

Contact tracing involves collecting people's information to track the spread of COVID-19 and to warn people who have been in the proximity of infected individuals. This measure is important to public health and safety during the pandemic. However, customers' concerns about the violation of their privacy might inhibit their cooperation in the contact tracing process, which poses a risk to public safety. This research investigates how to facilitate customers' cooperative behavior in contact tracing based on cognitive trust and affective trust. The findings show that cognitive trust increases people's willingness to disclose information and reduces their willingness to falsify it, whereas affective trust increases the willingness for both disclosure and falsification. This research contributes to the literature on customer data privacy by illuminating how cognitive and affective trust distinctly influence cooperative behavior, which has important implications for hospitality businesses.

[Sinonasal polyposis associated with a deficiency subclass immunoglobulin G: Place of substitution immunoglobulins]. / Polypose nasosinusienne associée à un déficit en sous-classes d'Immunoglobuline G: place de la substitution en immunoglobulines polyvalentes.

PURPOSE: To study the effect of the introduction of a substitution by intravenous Immunoglobulins (Ig IV) at patients with immunoglobulins G (IgG) subclasses deficiency and nasal polyposis. MATERIAL AND METHODS: Prospective study concerning five patients with IgG subclasses deficiency and nasal polyposis treated by Ig IV. Rhinologic, otologic and pulmonary symptoms, exacerbations of nasal polyposis, chronic otitis and asthma as well as the number of antibiotics and corticoids treatments were counted during the Ig IV substitution. OBJECTIVES: To study the association between IgIV substitution and the number of exacerbations of nasal polyposis, chronic otitis, asthma and the number of antibiotics and corticoids treatments in patients with IgG subclasses deficiency and nasal polyposis. RESULTS: Five patients with a IgG subclass deficiency and nasal polyposis were substituted. The number of antibiotics and corticoids cures increased at one patient and remained stable at four others. The number of sinus, ear and lung infections as well as the global rhinologic score of symptoms and the endoscopic stage of the nasal polyposis remained stable. In the absence of efficiency of the treatment, this one was interrupted at the end of 6 months for patients n° 1 and n° 3, 24 months for patient n° 4 and 42 months for patient n° 5. CONCLUSION: The current study failed to highlight clinical improvement in patients wih IgG subclasses deficiency and nasal polyposis treated by Ig IV. A previous study had not allowed to find a link between IgG subclasses deficiency and severity of nasal polyposis, what seems to be confirmed by the absence of improvement brought during the substitution of this deficit in the current study.

Dengue virus serotypes and related factors in children with dengue hemorrhagic fever in Southern Vietnam.

INTRODUCTION: After the Coronavirus Disease 2019 pandemic, a high number of cases and severe dengue in children were reported in some provinces in the south of Vietnam. This study aimed to determine the distribution of dengue virus serotypes and their correlation with demographic factors, disease severity, clinical manifestations, and laboratory findings. METHODOLOGY: This study employed a cross-sectional design. Ninety-six dengue-infected children admitted to Can Tho Children's Hospital between October 2022 and March 2023 were included. Confirmation of dengue infection was achieved through the real-time polymerase chain reaction (RT-PCR). RESULTS: Among the identified serotypes, DENV-2 accounted for the highest proportion (71.87%), followed by DENV-1 (23.96%), and DENV-4 (4.17%). DENV-3 was not detected. No significant demographic, disease severity, or laboratory differences were observed among the identified dengue serotypes. However, DENV-2 was associated with a higher occurrence of mucous membrane hemorrhages and gastrointestinal bleeding compared to other serotypes. CONCLUSIONS: Although DENV-2 was the most prevalent serotype responsible for dengue in children in southern Vietnam, it did not lead to more severe cases compared to other serotypes. This finding is crucial for evaluating the illness's prognosis.

Lung-to-Heart Nano-in-Micro Peptide Promotes Cardiac Recovery in a Pig Model of Chronic Heart Failure.

BACKGROUND: The lack of disease-modifying drugs is one of the major unmet needs in patients with heart failure (HF). Peptides are highly selective molecules with the potential to act directly on cardiomyocytes. However, a strategy for effective delivery of therapeutics to the heart is lacking. OBJECTIVES: In this study, the authors sought to assess tolerability and efficacy of an inhalable lung-to-heart nano-in-micro technology (LungToHeartNIM) for cardiac-specific targeting of a mimetic peptide (MP), a first-in-class for modulating impaired L-type calcium channel (LTCC) trafficking, in a clinically relevant porcine model of HF. METHODS: Heart failure with reduced ejection fraction (HFrEF) was induced in Göttingen minipigs by means of tachypacing over 6 weeks. In a setting of overt HFrEF (left ventricular ejection fraction [LVEF] 30% ± 8%), animals were randomized and treatment was started after 4 weeks of tachypacing. HFrEF animals inhaled either a dry powder composed of mannitol-based microparticles embedding biocompatible MP-loaded calcium phosphate nanoparticles (dpCaP-MP) or the LungToHeartNIM only (dpCaP without MP). Efficacy was evaluated with the use of echocardiography, invasive hemodynamics, and biomarker assessment. RESULTS: DpCaP-MP inhalation restored systolic function, as shown by an absolute LVEF increase over the treatment period of 17% ± 6%, while reversing cardiac remodeling and reducing pulmonary congestion. The effect was recapitulated ex vivo in cardiac myofibrils from treated HF animals. The treatment was well tolerated, and no adverse events occurred. CONCLUSIONS: The overall tolerability of LungToHeartNIM along with the beneficial effects of the LTCC modulator point toward a game-changing treatment for HFrEF patients, also demonstrating the effective delivery of a therapeutic peptide to the diseased heart.

The Prognostic Value of Olfactory Dysfunction in Patients with COVID-19: The COVIDORA Study.

BACKGROUND: Among all studies describing COVID-19 clinical features during the first wave of the pandemic, only a few retrospective studies have assessed the correlation between olfac-tory dysfunction (OD) and the evolution of disease severity. The main aim was to assess whether OD is a predictive factor of COVID-19 severity based on the patient's medical management (outpa-tient care, standard hospital admission, and ICU admission). METHODS: A national, prospective, mul-ticenter cohort study was conducted in 20 public hospitals and a public center for COVID-19 screen-ing. During the first wave of the pandemic, from 6 April to 11 May 2020, all patients tested positive for COVID-19 confirmed by RT-PCR underwent two follow-up ENT consultations within 10 days of symptom onset. The main outcome measures were the evolution of medical management (out-patient care, standard hospital admission, and ICU admission) at diagnosis and along the clinical course of COVID-19 disease. RESULTS: Among 481 patients included, the prevalence of OD was 60.7%, and it affected mostly female patients (74.3%) under 65 years old (92.5%), with fewer comor-bidities than patients with normal olfactory function. Here, 99.3% (290/292) of patients with OD presented with non-severe COVID-19 disease. Patients reporting OD were significantly less hospi-talized than the ones managed as outpatients, in either a standard medical unit or an ICU. Conclu-sions: As regards the clinical course of COVID-19 disease, OD could predict a decreased risk of hospitalization during the first wave of the pandemic.

Diagnostic mammography: identifying minimally acceptable interpretive performance criteria.

PURPOSE: To develop criteria to identify thresholds for the minimally acceptable performance of physicians interpreting diagnostic mammography studies. MATERIALS AND METHODS: In an institutional review board-approved HIPAA-compliant study, an Angoff approach was used to set criteria for identifying minimally acceptable interpretive performance for both workup after abnormal screening examinations and workup of a breast lump. Normative data from the Breast Cancer Surveillance Consortium (BCSC) was used to help the expert radiologist identify the impact of cut points. Simulations, also using data from the BCSC, were used to estimate the expected clinical impact from the recommended performance thresholds. RESULTS: Final cut points for workup of abnormal screening examinations were as follows: sensitivity, less than 80%; specificity, less than 80% or greater than 95%; abnormal interpretation rate, less than 8% or greater than 25%; positive predictive value (PPV) of biopsy recommendation (PPV2), less than 15% or greater than 40%; PPV of biopsy performed (PPV3), less than 20% or greater than 45%; and cancer diagnosis rate, less than 20 per 1000 interpretations. Final cut points for workup of a breast lump were as follows: sensitivity, less than 85%; specificity, less than 83% or greater than 95%; abnormal interpretation rate, less than 10% or greater than 25%; PPV2, less than 25% or greater than 50%; PPV3, less than 30% or greater than 55%; and cancer diagnosis rate, less than 40 per 1000 interpretations. If underperforming physicians moved into the acceptable range after remedial training, the expected result would be (a) diagnosis of an additional 86 cancers per 100,000 women undergoing workup after screening examinations, with a reduction in the number of false-positive examinations by 1067 per 100,000 women undergoing this workup, and (b) diagnosis of an additional 335 cancers per 100,000 women undergoing workup of a breast lump, with a reduction in the number of false-positive examinations by 634 per 100,000 women undergoing this workup. CONCLUSION: Interpreting physicians who fall outside one or more of the identified cut points should be reviewed in the context of an overall assessment of all their performance measures and their specific practice setting to determine if remedial training is indicated.

Pathogenic Role and Antibiotic Resistance of Methicillin-Resistant Staphylococcus aureus (MRSA) Strains Causing Severe Community-Acquired Pneumonia in Vietnamese Children.

In recent years, the pathogenic role and antibiotic resistance of methicillin-resistant Staphylococcus aureus (MRSA) strains causing severe community-acquired pneumonia (CAP) have received increasing attention in clinical practice. The aim of this study was to determine the rate of isolates of MRSA strains causing severe CAP in children and to assess their level of antibiotic resistance. The study design was cross-sectional. Children with severe CAP were sampled by nasopharyngeal aspiration for the culture, isolation, and identification of MRSA. Antimicrobial susceptibility testing was performed using the gradient diffusion method to determine the minimum inhibitory concentration (MIC) of antibiotics. Results: MRSA was identified as the second leading cause of severe CAP in Vietnamese children. The rate of isolates of S. aureus was 41/239 (17.5%), of which most were MRSA, at 32/41 (78.0%). MRSA strains were completely non-susceptible to penicillin (100%), more resistant to clindamycin and erythromycin, less sensitive to ciprofloxacin and levofloxacin, and fully susceptible to vancomycin and linezolid, with a 32-fold decreased MIC90 for vancomycin (0.5 mg/L) and a 2-fold decreased MIC90 for linezolid (4 mg/L). Therefore, vancomycin and linezolid may be appropriate options for severe CAP identified by MRSA.

A comprehensive evaluation of polygenic score and genotype imputation performances of human SNP arrays in diverse populations.

Regardless of the overwhelming use of next-generation sequencing technologies, microarray-based genotyping combined with the imputation of untyped variants remains a cost-effective means to interrogate genetic variations across the human genome. This technology is widely used in genome-wide association studies (GWAS) at bio-bank scales, and more recently, in polygenic score (PGS) analysis to predict and stratify disease risk. Over the last decade, human genotyping arrays have undergone a tremendous growth in both number and content making a comprehensive evaluation of their performances became more important. Here, we performed a comprehensive performance assessment for 23 available human genotyping arrays in 6 ancestry groups using diverse public and in-house datasets. The analyses focus on performance estimation of derived imputation (in terms of accuracy and coverage) and PGS (in terms of concordance to PGS estimated from whole-genome sequencing data) in three different traits and diseases. We found that the arrays with a higher number of SNPs are not necessarily the ones with higher imputation performance, but the arrays that are well-optimized for the targeted population could provide very good imputation performance. In addition, PGS estimated by imputed SNP array data is highly correlated to PGS estimated by whole-genome sequencing data in most cases. When optimal arrays are used, the correlations of PGS between two types of data are higher than 0.97, but interestingly, arrays with high density can result in lower PGS performance. Our results suggest the importance of properly selecting a suitable genotyping array for PGS applications. Finally, we developed a web tool that provides interactive analyses of tag SNP contents and imputation performance based on population and genomic regions of interest. This study would act as a practical guide for researchers to design their genotyping arrays-based studies. The tool is available at: https://genome.vinbigdata.org/tools/saa/ .

Prevalence and Characteristics of Altered Sense of Smell/Taste During Covid-19 first wave: A French Nationwide Cross-sectional Study.

AIM: Altered sense of smell and/or taste is a leading symptom of SARS-CoV-2 infection, but its prevalence at a population-level is unknown. METHODS: From a questionnaire addressed to a representative subset of the French general adult (≥18-year) population over a 6-week period during the first French lockdown (April 7 to May 19 2020), self-reported new cases of altered sense of smell and/or taste were collected. RESULTS: From 29,660 participants, new altered sense of smell and/or taste was 2.18% and 2.11% after direct standardization on the French population representing more than 1,110,000 subjects in France. Moreover, 0.5% of participants reported a positive SARS-CoV-2 test, among which 47.4% reported a newly altered sense of smell and/or taste. Male participants, younger ones together with those presenting with chronic condition had higher odds of reporting a newly altered sense of smell and/or taste. CONCLUSION: This study provides an accurate estimate of new cases of altered sense of smell and/or taste in the general population at a nationwide level during the Covid-19 first wave.

Effects of BNP and Sacubitrilat/Valsartan on Atrial Functional Reserve and Arrhythmogenesis in Human Myocardium.

Background: Although the angiotensin receptor-neprilysin inhibitor (ARNI) sacubitril/valsartan started a new era in heart failure (HF) treatment, less is known about the tissue-level effects of the drug on the atrial myocardial functional reserve and arrhythmogenesis. Methods and Results: Right atrial (RA) biopsies were retrieved from patients (n = 42) undergoing open-heart surgery, and functional experiments were conducted in muscle strips (n = 101). B-type natriuretic peptide (BNP) did not modulate systolic developed force in human myocardium during ß-adrenergic stimulation, but it significantly reduced diastolic tension (p < 0.01) and the probability of arrhythmias (p < 0.01). In addition, patient's plasma NTproBNP positively correlated with isoproterenol-induced contractile reserve in atrial tissue in vitro (r = 0.65; p < 0.01). Sacubitrilat+valsartan (Sac/Val) did not show positive inotropic effects on atrial trabeculae function but reduced arrhythmogeneity. Atrial and ventricular biopsies from patients with end-stage HF (n = 10) confirmed that neprilysin (NEP) is equally expressed in human atrial and ventricular myocardium. RA NEP expression correlates positively with RA ejection fraction (EF) (r = 0.806; p < 0.05) and left ventricle (LV) NEP correlates inversely with left atrial (LA) volume (r = -0.691; p < 0.05). Conclusion: BNP ameliorates diastolic tension during adrenergic stress in human atrial myocardium and may have positive long-term effects on the inotropic reserve. BNP and Sac/Val reduce atrial arrhythmogeneity during adrenergic stress in vitro. Myocardial NEP expression is downregulated with declining myocardial function, suggesting a compensatory mechanism in HF.

Communicating With Breast Imaging Patients During the COVID-19 Pandemic: Impact on Patient Care and Physician Wellness.

OBJECTIVE: Assess the impact of COVID-19 on patient-breast radiologist interactions and evaluate the relationship between safety measure-constrained communication and physician wellbeing. METHODS: A 41-question survey on the perceived effect of COVID-19 on patient care was distributed from June 2020 to September 2020 to members of the Society of Breast Imaging and the National Consortium of Breast Centers. Non-radiologists and international members were excluded. Anxiety and psychological distress scores were calculated. A multivariable logistic model was used to identify demographic and mental health factors associated with responses. RESULTS: Five hundred twenty-five surveys met inclusion criteria (23% response rate). Diminished ability to fulfill patients' emotional needs was reported by 46% (221/479), a response associated with younger age (OR, 0.8 per decade; P < 0.01), higher anxiety (OR, 2.3; P < 0.01), and higher psychological distress (OR, 2.2; P = 0.04). Personal protective equipment made patient communication more difficult for 88% (422/478), a response associated with younger age (OR, 0.8 per decade; P = 0.008), female gender (OR, 1.9; P < 0.01), and greater anxiety (OR, 2.6; P = 0.001). The inability to provide the same level of care as prior to COVID-19 was reported by 37% (177/481) and was associated with greater anxiety (OR, 3.4; P < 0.001) and psychological distress (OR, 1.7; P = 0.03). CONCLUSION: The majority of breast radiologists reported that COVID-19 has had a negative impact on patient care. This perception was more likely among younger radiologists and those with higher levels of anxiety and psychological distress.

COVID-19 and Breast Radiologist Wellness: Impact of Gender, Financial Loss, and Childcare Need.

PURPOSE: The purpose of this study was to evaluate the emotional and financial impact of coronavirus disease 2019 (COVID-19) on breast radiologists to understand potential consequences on physician wellness and gender disparities in radiology. METHODS: A 41-question survey was distributed from June to September 2020 to members of the Society of Breast Imaging and the National Consortium of Breast Centers. Psychological distress and financial loss scores were calculated on the basis of survey responses and compared across gender and age subgroups. A multivariate logistic model was used to identify factors associated with psychological distress scores. RESULTS: A total of 628 surveys were completed (18% response rate); the mean respondent age was 52 ± 10 years, and 79% were women. Anxiety was reported by 68% of respondents, followed by sadness (41%), sleep problems (36%), anger (25%), and depression (23%). A higher psychological distress score correlated with female gender (odds ratio [OR], 1.9; P = .001), younger age (OR, 0.8 per SD; P = .005), and a higher financial loss score (OR, 1.4; P < .0001). Participants whose practices had not initiated wellness efforts specific to COVID-19 (54%) had higher psychological distress scores (OR, 1.4; P = .03). Of those with children at home, 38% reported increased childcare needs, higher in women than men (40% versus 29%, P < .001). Thirty-seven percent reported that childcare needs had adversely affected their jobs, which correlated with higher psychological distress scores (OR, 2.2-3.3; P < .05). CONCLUSIONS: Psychological distress was highest among younger and female respondents and those with greater pandemic-specific childcare needs and financial loss. Practice-initiated COVID-19-specific wellness efforts were associated with decreased psychological distress. Policies are needed to mitigate pandemic-specific burnout and worsening gender disparities.

Impact of COVID-19 on Breast Imaging Practice Operations and Recovery Efforts: A North American Study.

OBJECTIVE: To assess the impact of the COVID-19 pandemic on breast imaging facilities' operations and recovery efforts across North America. METHODS: A survey on breast imaging facilities' operations and strategies for recovery during the COVID-19 pandemic was distributed to the membership of the Society of Breast Imaging and National Consortium of Breast Centers from June 4, 2020, to July 14, 2020. A descriptive summary of responses was performed. Comparisons were made between demographic variables of respondents and questions of interest using a Pearson chi-square test. RESULTS: There were 473 survey respondents (response rate of 13%). The majority of respondents (70%; 332/473) reported 80%-100% breast imaging volume reduction, with 94% (447/473) reporting postponement of screening mammography. The majority of respondents (97%; 457/473) continued to perform biopsies. There were regional differences in safety measures taken for staff (P = 0.004), with practices in the West more likely reporting no changes in the work environment compared to other regions. The most common changes to patients' experience included spacing out of furniture in waiting rooms (94%; 445/473), limiting visitors (91%; 430/473), and spacing out appointments (83%). A significantly higher proportion of practices in the Northeast (95%; 104/109) initiated patient scheduling changes compared to other regions (P = 0.004). CONCLUSION: COVID-19 had an acute impact on breast imaging facilities. Although common national operational patterns emerged, geographic variability was notable in particular in recovery efforts. These findings may inform future best practices for delivering breast imaging care amid the ongoing and geographically shifting COVID-19 pandemic.

Identifying minimally acceptable interpretive performance criteria for screening mammography.

PURPOSE: To develop criteria to identify thresholds for minimally acceptable physician performance in interpreting screening mammography studies and to profile the impact that implementing these criteria may have on the practice of radiology in the United States. MATERIALS AND METHODS: In an institutional review board-approved, HIPAA-compliant study, an Angoff approach was used in two phases to set criteria for identifying minimally acceptable interpretive performance at screening mammography as measured by sensitivity, specificity, recall rate, positive predictive value (PPV) of recall (PPV(1)) and of biopsy recommendation (PPV(2)), and cancer detection rate. Performance measures were considered separately. In phase I, a group of 10 expert radiologists considered a hypothetical pool of 100 interpreting physicians and conveyed their cut points of minimally acceptable performance. The experts were informed that a physician's performance falling outside the cut points would result in a recommendation to consider additional training. During each round of scoring, all expert radiologists' cut points were summarized into a mean, median, mode, and range; these were presented back to the group. In phase II, normative data on performance were shown to illustrate the potential impact cut points would have on radiology practice. Rescoring was done until consensus among experts was achieved. Simulation methods were used to estimate the potential impact of performance that improved to acceptable levels if effective additional training was provided. RESULTS: Final cut points to identify low performance were as follows: sensitivity less than 75%, specificity less than 88% or greater than 95%, recall rate less than 5% or greater than 12%, PPV(1) less than 3% or greater than 8%, PPV(2) less than 20% or greater than 40%, and cancer detection rate less than 2.5 per 1000 interpretations. The selected cut points for performance measures would likely result in 18%-28% of interpreting physicians being considered for additional training on the basis of sensitivity and cancer detection rate, while the cut points for specificity, recall, and PPV(1) and PPV(2) would likely affect 34%-49% of practicing interpreters. If underperforming physicians moved into the acceptable range, detection of an additional 14 cancers per 100000 women screened and a reduction in the number of false-positive examinations by 880 per 100000 women screened would be expected. CONCLUSION: This study identified minimally acceptable performance levels for interpreters of screening mammography studies. Interpreting physicians whose performance falls outside the identified cut points should be reviewed in the context of their specific practice settings and be considered for additional training.

Attenuated secretion of very low density lipoproteins from McA-RH7777 cells treated with eicosapentaenoic acid is associated with impaired utilization of triacylglycerol synthesized via phospholipid remodeling.

In McA-RH7777 cells stably expressing human apolipoprotein (apo) B100, treatment with oleic acid (18:1(n-9)) promoted whereas treatment with eicosapentaenoic acid (EPA, 20:5(n-3)) attenuated assembly and secretion of VLDL. Under conditions where the cells were cultured in the presence of 20% serum, EPA (0.4 mM) had marginal effect on the secretion of total apoB100 (determined by pulse-chase analysis) but decreased (by 50%) secretion of triacylglycerol (TG), indicating that the inhibitory effect of EPA was exerted primarily on TG-rich VLDL. Analysis of phospholipid mass and species by tandem mass spectrometry showed increased phosphatidylethanolamine (PE) in EPA-treated cells, the increase was significant in the distal Golgi membranes (by 170%) and endoplasmic reticulum (by 116%). Lipid pulse-chase studies showed a major distinction between phospholipid species containing 20:5(n-3) and 18:1(n-9), which in turn was associated with distinct compartmentalization of TG containing 20:5(n-3) or 18:1(n-9) between cytosol and microsomes and their recruitment during VLDL assembly. Thus, 18:1-TG was secreted as VLDL but 20:5-TG was not. These results suggest that EPA attenuation of VLDL secretion is associated with impaired utilization of TG derived from phospholipid remodeling.

Clinical efficacy and cost-effectiveness of newborn screening for medium chain acyl-CoA dehydrogenase deficiency using tandem mass spectrometry.

OBJECTIVE: To determine the clinical efficacy and cost-effectiveness of newborn screening for MCADD using tandem mass spectrometry (MS/MS) compared with clinical diagnosis within the Canadian context. DESIGN AND METHODS: A systematic review of the clinical and economic literature was performed. For primary economic analysis, a decision-tree model was built based on the available information, the impact of newborn screening on the health care and the relevant Canadian data. RESULTS: Twenty-one clinical and two economic studies met the selection criteria. Mean incidence of MCADD was approximately 1:16,000. Clinical sensitivity and specificity were 100% and 99.99%, respectively. Screening significantly lowered morbidity and mortality. Both economic studies showed that screening for MCADD using MS/MS was cost-effective if willingness-to-pay was US 50,000 dollars. Our primary economic analysis showed that screening was cost-effective based on the cost-effective threshold of C 20,000 dollars per QALY. CONCLUSION: Screening consumes more resources than no screening but attains better health outcomes.

Recommendations and supporting evidence in guidelines for referral of patients to sleep laboratories.

At the request of Canadian health ministries, we reviewed recommendations in guidelines prepared by professional bodies on the referral of individuals to sleep laboratories. Searching electronic databases and the Internet, we found 37 guidelines that covered 18 applications of sleep laboratory investigation including obstructive sleep apnea, other respiratory disorders, obstructive sleep apnea and other conditions in children, sudden infant death syndrome, treatment for snoring, insomnia, depression with insomnia, narcolepsy, restless legs syndrome/periodic limb movement disorder, parasomnias and circadian rhythm disorders. We identified recommendations on referral of patients for sleep studies and assessed the quality and relevance of evidence cited in support of these. Of 81 recommendations, 46 were supported by evidence from primary investigations. Only six cases cited evidence from well-conducted, prospective controlled studies. Evidence was highly relevant in 18 cases, of some relevance in 22 and of little or no relevance in six. No evidence was provided in support of 31 recommendations, and in four cases the guideline had identified an absence of available evidence. Although the publications from professional bodies that were reviewed contain much detailed information, evidence supporting many recommendations is limited. There is a need for further, good quality, studies of many sleep laboratory applications.