The safety and tolerability of adenosine as a pharmacological stressor in stress perfusion cardiac magnetic resonance imaging in the Chinese population.

OBJECTIVE: To investigate the safety profile and effectiveness of adenosine as a pharmacological stressor in patients with known or suspected coronary artery disease who underwent cardiac magnetic resonance imaging perfusion study. SETTING: Regional hospital, Hong Kong. PATIENTS: All patients who underwent adenosine stress cardiac magnetic resonance imaging from May 2013 to August 2013 were prospectively interviewed during the scan. MAIN OUTCOME MEASURES: Common side-effects of adenosine as well as any other discomfort experienced during the scan were recorded. Haemodynamic changes including systolic and diastolic blood pressure and pulse rate before and during adenosine administration were also recorded. RESULTS: There were 98 consecutive patients with a mean (± standard deviation) age of 64.0 ± 11.4 years (range, 10-83 years) and mean body weight of 67.5 ± 12.0 kg. Male-to-female ratio was 2.5:1. Of the 98 patients interviewed, 62 (63.3%) experienced one or more adenosine-associated adverse effects. Chest discomfort was most frequently experienced (48.0%), followed by dyspnoea (29.6%) and headache (20.4%). No life-threatening event occurred. Following adenosine administration, a significant rise in pulse rate (75.1 ± 14.3 vs 93.2 ± 14.7 beats/min; P<0.01) and a significant drop in diastolic blood pressure (75.1 ± 13.3 vs 68.0 ± 13.9 mm Hg; P<0.01) were noted. There was a general decrease in systolic blood pressure, although no statistically significant difference was observed (144.9 ± 17.6 vs 143.1 ± 21.4 mm Hg; P=0.18). CONCLUSION: Adenosine stress cardiac magnetic resonance perfusion study is safe and well tolerated in clinical practice.

Victimization and depression among youth with disabilities in the US child welfare system.

AIM: This study aimed to examine the prevalence of victimization among a United States-wide cohort of youth with disabilities (YWD) investigated for maltreatment in the child welfare system (CWS) and their correlation with mental health. METHODS: Data were drawn from baseline interviews in the second National Survey of Child and Adolescent Well-Being, a national representative survey of youth involved in the CWS. Interviews took place between 2008 and 2009 and included 675 youth, 11-17 years old and residing with biological families across 83 counties nationwide. The sample consisted of 405 females (60.1%) and 270 males (39.9%), mean age = 13.5 years. We identified YWD if they reported one or more physical or neurodevelopmental health condition (n = 247). Reported victimization experiences and Children's Depression Inventory (CDI) scores were analysed using weighted regression analyses. RESULTS: One-quarter of YWD in the CWS reported three or more victimizations during the prior year compared with 19% of youth without disabilities. The odds of YWD reporting a one-unit increase in level of victimization was 75% higher (P < 0.05) than youth without disabilities. Prevalence of clinical depression was significantly higher among YWD (14 vs. 5.5%; P < 0.05). Unlike youth without disabilities, the odds of clinical depression were 92% higher for every one-unit increase in victimization among YWD, controlling for covariates (P < 0.05). Of CWS-involved youth who reported three or more victimizations, 24.4% of YWD and 2.2% of non-disabled youth had CDI scores in the clinical range. CONCLUSION: YWDs in the US CWS are at high risk of experiencing victimization and clinical depression. Our findings suggest that health professionals need to screen CWS-involved YWD for multiple forms of victimization, and develop and implement trauma-informed services that target the mental health sequelae that may jeopardize their independence in adulthood.

IL28B genetic variations are associated with high sustained virological response (SVR) of interferon-α plus ribavirin therapy in Taiwanese chronic HCV infection.

Chronic hepatitis C virus (HCV) infection patients exhibit different sustained virological responses (SVRs) following the treatment with pegylated interferon-α (IFN-α) and ribavirin. Genome-wide association studies consistently linked SVR of IFN-α-based therapy to the IL28B single-nucleotide polymorphisms (SNPs) on chromosome 19q.13 in various populations. This study was undertaken to investigate the association of IL28B SNPs with SVR in a cohort of Taiwanese chronic HCV patients. Ten SNPs of IL28B were genotyped in 728 chronic HCV patients and 960 healthy controls. Genotype distributions, allele frequencies and haplotypes were tested for SVR and susceptibility in Taiwanese chronic HCV patients. Non-genotype 1 infection (adjusted P=3.3 × 10(-12), odds ratio (OR) 0.179; 95% confidence interval (CI): 0.110-0.290) and low HCV viral load (<400 000 IU ml(-1)) (adjusted P=3.5 × 10(-9), OR 0.299; 95% CI: 0.200-0.446) were two major factors identified for high SVR. Notably, eight IL28B SNPs including previously described disease-associated SNPs (Trend test P=0.005) were significantly associated with SVR. Our data indicate that IL28B polymorphisms are the essential contributing factors for high SVR in Taiwanese chronic HCV patients. Combination of virus genotyping and host genetic data may be used to select the optimal treatment regimes in IFN-based therapy.

Analysis of the optimal cut-point for HIV-p24 antigen testing to diagnose HIV infection in HIV-exposed children from resource-constrained settings.

BACKGROUND: Nucleic-acid-testing (NAT) to diagnose HIV infection in children under age 18 months provides a barrier to HIV-testing in exposed children from resource-constrained settings. The ultrasensitive HIV-p24-antigen (Up24) assay is cheaper and easier to perform and is sensitive (84-98%) and specific (98-100%). The cut-point optical density (OD) selected for discriminating between positive and negative samples may need assessment due to regional differences in mother-to-child HIV-transmission rates. OBJECTIVES: We used receiver operator characteristics (ROC) curves and logistic regression analyses to assess the effect of various cut-points on the diagnostic performance of Up24 for HIV-infection status among HIV-exposed children. Positive and negative predictive values at different rates of disease prevalence were also estimated. STUDY DESIGN: A study of Up24 testing on dried blood spot (DBS) samples collected from 278 HIV-exposed Haitian children, 3-24-months of age, in whom HIV-infection status was determined by NAT on the same DBS card. RESULTS: The sensitivity and specificity of Up24 varied by the cut-point-OD value selected. At a cut-point-OD of 8-fold the standard deviation of the negative control (NCSD), sensitivity and specificity of Up24 were maximized [87.8% (95% CI, 83.9-91.6) and 92% (95% CI, 88.8-95.2), respectively]. In lower prevalence settings (5%), positive and negative predictive values of Up24 were maximal (75.9% and 98.8%, respectively) at a cut-point-OD that was 15-fold the NCSD. CONCLUSIONS: In low prevalence settings, a high degree of specificity can be achieved with Up24 testing of HIV-exposed children when a higher cut-point OD is used; a feature that may facilitate more frequent use of Up24 antigen testing for HIV-exposed children.

Axial tensile fracture of microcrystalline cellulose compacts.

An adapted tensile stress methodology for the fracture of microcrystalline cellulose (MCC) tablets has been investigated and implemented. The application of the generally applied linear elastic fracture mechanic (LEFM) parameters used to describe the fracture behaviour of these porous systems has been discussed. The application of an effective crack length concept, comprising of the notch depth and a process zone length designated delta c, has enabled the localised non-linear response of the MCC tablets to be characterised in a quantified manner. The requirement of the composite value delta c is postulated to be a direct result of the internal properties of the tablet formed during the compaction process due to its strong dependence on porosity. The high compact relative density creates a greater possibility for both local small-scale plastic yielding at the crack tip, commonly found in polymer materials and microcracking ahead of the crack tip, typically observed in the fracture of ceramics. The extrapolated value of KIC0 of 0.72 MPa m0.5 found in this work lies within the range found in literature for this material indicating that the adopted procedure is acceptable for the determination of the resistance to fracture of MCC compacts.

Surgical repair of postinfarction ventricular septal defect.

BACKGROUND: Rupture of the interventricular septum complicates 1% to 2% of all acute myocardial infarction patients and its natural course is ominous. The purpose of this study is to present our experience with surgical ventricular septal defect (VSD) repair and examine the possible risk factors and explanations for surgical mortality. METHODS: Fourteen patients underwent repair of postinfarction VSD from 1996 to 1998 at the Taipei Veterans General Hospital. Thirteen patients were in New York Heart Association (NYHA) Functional Class IV and one was in Functional Class III. Eleven patients were in cardiogenic shock with intra-aortic balloon pumps (IABPs) prior to surgery. The operative techniques for VSD repair range from extensive infarctectomy with reconstruction of the septum and the right and left ventricular free walls using single or double patches, to minimal or no infarctectomy with closure of the VSD by excluding the infarcted muscle from the left ventricular cavity and leaving the right ventricle intact. RESULTS: Overall surgical mortality occurred in four patients. All deaths occurred in patients with cardiogenic shock, two with anterior VSD and two with posterior VSD. Three late survivors had limited exercise tolerance with NYHA Functional Class II to III. Left ventricular function was moderately impaired in most patients with a mean nuclear scan ejection fraction of 0.32. However, all patients were elderly and adapted to their residual symptoms without significant life-style changes. CONCLUSIONS: The surgical mortality for treating patients with postinfarction VSD has decreased with improvements in surgical technique. Rapid diagnosis, appropriate preoperative management and delicate surgical repair improve the overall results and help to attain long-term survival.