1,940 research outputs found

    Coronary microvascular ischemia in hypertrophic cardiomyopathy - a pixel-wise quantitative cardiovascular magnetic resonance perfusion study.

    Get PDF
    BACKGROUND: Microvascular dysfunction in HCM has been associated with adverse clinical outcomes. Advances in quantitative cardiovascular magnetic resonance (CMR) perfusion imaging now allow myocardial blood flow to be quantified at the pixel level. We applied these techniques to investigate the spectrum of microvascular dysfunction in hypertrophic cardiomyopathy (HCM) and to explore its relationship with fibrosis and wall thickness. METHODS: CMR perfusion imaging was undertaken during adenosine-induced hyperemia and again at rest in 35 patients together with late gadolinium enhancement (LGE) imaging. Myocardial blood flow (MBF) was quantified on a pixel-by-pixel basis from CMR perfusion images using a Fermi-constrained deconvolution algorithm. Regions-of-interest (ROI) in hypoperfused and hyperemic myocardium were identified from the MBF pixel maps. The myocardium was also divided into 16 AHA segments. RESULTS: Resting MBF was significantly higher in the endocardium than in the epicardium (mean ± SD: 1.25 ± 0.35 ml/g/min versus 1.20 ± 0.35 ml/g/min, P < 0.001), a pattern that reversed with stress (2.00 ± 0.76 ml/g/min versus 2.36 ± 0.83 ml/g/min, P < 0.001). ROI analysis revealed 11 (31%) patients with stress MBF lower than resting values (1.05 ± 0.39 ml/g/min versus 1.22 ± 0.36 ml/g/min, P = 0.021). There was a significant negative association between hyperemic MBF and wall thickness (β = −0.047 ml/g/min per mm, 95% CI: −0.057 to −0.038, P < 0.001) and a significantly lower probability of fibrosis in a segment with increasing hyperemic MBF (odds ratio per ml/g/min: 0.086, 95% CI: 0.078 to 0.095, P = 0.003). CONCLUSIONS: Pixel-wise quantitative CMR perfusion imaging identifies a subgroup of patients with HCM that have localised severe microvascular dysfunction which may give rise to myocardial ischemia

    Apheresis as novel treatment for refractory angina with raised lipoprotein(a): a randomised controlled trial

    Get PDF
    Aims To determine the clinical impact of lipoprotein apheresis in patients with refractory angina and raised lipoprotein(a) > 500 mg/L on the primary end point of quantitative myocardial perfusion, as well as secondary end points including atheroma burden, exercise capacity, symptoms, and quality of life. Methods We conducted a single-blinded randomized controlled trial in 20 patients with refractory angina and raised lipoprotein(a) > 500 mg/L, with 3 months of blinded weekly lipoprotein apheresis or sham, followed by crossover. The primary endpoint was change in quantitative myocardial perfusion reserve (MPR) assessed by cardiovascular magnetic resonance. Secondary endpoints included measures of atheroma burden, exercise capacity, symptoms and quality of life. Results The primary endpoint, namely MPR, increased following apheresis (0.47; 95% CI 0.31–0.63) compared with sham (−0.16; 95% CI − 0.33–0.02) yielding a net treatment increase of 0.63 (95% CI 0.37–0.89; P < 0.001 between groups). Improvements with apheresis compared with sham also occurred in atherosclerotic burden as assessed by total carotid wall volume (P < 0.001), exercise capacity by the 6 min walk test (P = 0.001), 4 of 5 domains of the Seattle angina questionnaire (all P < 0.02) and quality of life physical component summary by the short form 36 survey (P = 0.001). Conclusion Lipoprotein apheresis may represent an effective novel treatment for patients with refractory angina and raised lipoprotein(a) improving myocardial perfusion, atheroma burden, exercise capacity and symptoms

    The time-dependent rearrangement of the epithelial basement membrane in human skin wounds

    Get PDF
    In 62 human skin wounds (surgical wounds, stab wounds and lacerations after surgical treatment) we analyzed the immunohistochemical localization of collagen IV in the epithelial basement membrane. In 27 of these wounds the distribution of collagen VII, which represents a specific component of the basement membrane of stratified epithelia, was also analyzed. We were able to demonstrate a virtually identical co-distribution of both collagen IV and VII in the wound area with no significant time-dependent differences in the appearance of both collagen types. Fragments of the epithelial basement membrane could be detected in the wound area from as early as 4 days after wounding and after 8 days a complete restitution of the epithelial basement membrane was observed. In all cases with a wound age of more than 21 days the basement membrane was completely reformed over the former lesional area. The period between 8 and 21 days after wounding was characterized by a wide variability ranging from complete restitution to deposition of basement membrane fragments or total lack of the epidermal basement membrane

    Infection with hepatitis B virus carrying novel pre-S/S gene mutations in female siblings vaccinated at birth: two case reports

    Get PDF
    <p>Abstract</p> <p>Introduction</p> <p>After the initiation of a mass hepatitis B vaccination program in Taiwan, the prevalence of hepatitis B virus infection has declined progressively. However, about 1 percent of the young generation, who received hepatitis B vaccination at birth, remain carriers. Infection with vaccine-escape hepatitis B virus mutants always occurs shortly after birth. Here, we report two female siblings in whom the infection occurred in their adolescence. This report raises the question of whether a booster for hepatitis B vaccination is needed.</p> <p>Case presentation</p> <p>Two 19 and 14-year-old Taiwanese female siblings were born to a mother infected with hepatitis B virus and received a complete course of hepatitis B vaccination at birth. They remained negative for serum hepatitis B surface antigen and positive for serum anti-hepatitis B surface antibody throughout their childhood. However, both were infected with the hepatitis B virus in their adolescence. Hepatitis B virus DNA was extracted from serum samples from the mother and two siblings. Hepatitis B virus pre-S/S sequence was amplified by polymerase chain reaction followed by nucleotide sequencing. When compared with the sequence obtained from the mother, multiple amino acid substitutions located near or in the major hydrophilic region of the surface antigen were identified in the elder sister. Four of these mutations (sL97S, sL98S, sG102R, and sA159P) were novel. A novel in-frame deletion (14 amino acids deleted, pre-S 127-140) was found in the hepatitis B virus pre-S2 region in the younger sister.</p> <p>Conclusions</p> <p>Despite having received hepatitis B vaccination at birth, hepatitis B virus infection can still occur in adolescence with the emergence of novel mutations in the pre-S/S gene. This is a rare event and, to the best of our knowledge, has not been previously reported.</p

    A novel immunomodulatory function of neutrophils on rhinovirus-Activated monocytes in vitro

    Get PDF
    © 2016 Published by the BMJ Publishing Group Limited. Background Rhinovirus (RV) infections are the major precipitant of asthma exacerbations. While neutrophilic lung inflammation occurs during such infections, its role remains unclear. Neutrophilic inflammation is associated with increased asthma severity and steroid refractory disease. Neutrophils are vital for controlling infections but also have immunomodulatory functions. Previously, we found that neutrophils respond to viral mimetics but not replication competent RV. We aimed to investigate if neutrophils are activated and/or modulate immune responses of monocytes during RV16 infection. Methods Primary human monocytes and autologous neutrophils were cocultured with or without RV16, in direct contact or separated by transwells. RV16-stimulated monocytes were also exposed to lysed neutrophils, neutrophil membrane components or soluble neutrophil intracellular components. Interleukin 6 (IL-6) and C-X-C motif (CXC)L8 mRNA and proteins were measured by quantitative PCR and ELISA at 24â €..hours. Results RV16 induced IL-6 and CXCL8 in monocytes, but not neutrophils. RV16-induced IL-6 and CXCL8 from monocytes was reduced in the presence of live neutrophils. Transwell separation abolished the inhibitory effects. Lysed neutrophils inhibited RV16-induced IL-6 and CXCL8 from monocytes. Neutrophil intracellular components alone effectively inhibited RV16-induced monocyte-derived IL-6 and CXCL8. Neutrophil intracellular components reduced RV16-induced IL-6 and CXCL8 mRNA in monocytes. Conclusions Cell contact between monocytes and neutrophils is required, and preformed neutrophil mediator(s) are likely to be involved in the suppression of cytokine mRNA and protein production. This study demonstrates a novel regulatory function of neutrophils on RV-Activated monocytes in vitro, challenging the paradigm that neutrophils are predominantly proinflammatory

    Women's preference for cesarean delivery and differences between Taiwanese women undergoing different modes of delivery

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The rate of cesarean delivery was 35% in 2007 in Taiwan. It is unclear how many of the cesarean deliveries were without medical indications. Women's preference for cesarean delivery during their course of pregnancy has rarely been studied and therefore our objectives were to examine rate of cesarean deliveries without medical indications, to explore women's preference for cesarean delivery as their gestation advances, and to compare background and perinatal factors among women who underwent different modes of delivery in Taiwan.</p> <p>Methods</p> <p>This prospective study applied a longitudinal design. The study participants were 473 women who received prenatal care at four hospitals in Taipei and answered structured questionnaires at 20 to 24 weeks of pregnancy, 34 to 36 weeks of pregnancy, and 5 to 7 weeks after delivery.</p> <p>Results</p> <p>Of the 151 women (31.9%) who had cesarean deliveries, 19.9% were without medical indication. Three indications: malpresentation, prior cesarean section, and dysfunctional labor together accounted for 82.6% of cesarean section with medical indications. The prevalence of maternal preference for cesarean delivery was found to be 12.5% and 17.5% during the second and third trimester, respectively. Of the women who preferred cesarean delivery during the second trimester, 93.2% eventually had a cesarean delivery. Women who were older, with older spouses, and who had health problems before or during pregnancy were more likely to have cesarean deliveries.</p> <p>Conclusions</p> <p>About 20% of cesarean deliveries were without medical indications. Women's preference for cesarean delivery during the second trimester predicts subsequent cesarean delivery. Counseling regarding mode of delivery should be offered early in pregnancy, especially for women who are older or with older spouses, have health problems, or had a prior cesarean section.</p

    Prevalence of invasive fungal disease in hematological patients at a tertiary university hospital in Singapore

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The use of newer azoles as prophylaxis in hematological patients undergoing stem cell transplantation or immunosuppressive chemotherapy has been shown to decrease the risk of developing invasive fungal disease (IFD). However, the cost-effectiveness of such a strategy is dependent on the local epidemiology of IFD. We conducted an audit of hematological patients with IFD in our institution in order to derive the prevalence and types of IFD that occur locally.</p> <p>Findings</p> <p>We conducted a retrospective chart review of all hematological patients who developed possible, probable or definite IFD according to EORTC/MSG criteria in the period from Oct 2007 to Apr 2010. The prevalence of IFD was determined via correlation with institutional database records of all hematological patients treated at our institution over the same time period.</p> <p>There were 39 cases of IFD diagnosed during the study period, with 8 (20.5%) possible, 19 (48.7%) probable and 12 (30.8%) definite cases of IFD. <it>Aspergillus </it>spp. accounted for 83.9% of all probable and definite infections. There was 1 case each of <it>Rhinocladelia </it>spp., <it>Coprinopsis cinerea</it>, <it>Exserohilum </it>spp. sinusitis and <it>Rhizopus </it>spp. sinusitis. IFD occurred in 12 of 124 (9.7%) AML and 4 of 103 (3.9%) ALL patients treated at our institution respectively. There were 10 (16.1%) infections among 62 allogeneic HSCT recipients, six of whom were having concurrent graft-versus-host disease (GVHD). Five other cases occurred after allogeneic HSCT failure, following salvage chemotherapy for disease relapse. The prevalence of IFD during induction chemotherapy was 8.9% (11 of 124 cases) for AML and 1.0% (1 of 103 cases) for ALL. Fluconazole prophylaxis had been provided for 28 out of the 39 (71.8%) cases, while 4 (10.3%) were on itraconazole prophylaxis. The in-hospital mortality was 28.2% (11 of 39 cases), of which 5 (12.8%) deaths were attributed to IFD.</p> <p>Conclusions</p> <p>The burden of IFD is high in our institution, especially in allogeneic HSCT recipients and patients on induction chemotherapy for AML. A prophylactic strategy directed against invasive mould infections for local high-risk patients may be considered as the comparative costs of treatment, prolonged hospitalisation and subsequent delayed chemotherapy favours such an approach.</p
    corecore