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31.
In Ae Kim Hyun Suk Yang Wan Seop Kim Hyun Keun Chee 《Journal of Korean medical science》2015,30(9):1367-1372
Fulminant myocarditis has been defined as the clinical manifestation of cardiac inflammation with rapid-onset heart failure and cardiogenic shock. We report on the case of a 23-yr-old woman with pathology-proven fulminant lymphocytic myocarditis presenting shock with elevated cardiac troponin I and ST segments in V1-2, following sustained ventricular tachycardia and a complete atrioventricular block. About 55 min of intensive cardio-pulmonary resuscitation, with extracorporeal membrane oxygenation support, bridged the patient to orthotopic heart transplantation. The explanted heart revealed diffuse lymphocytic infiltration and myocyte necrosis in all four cardiac chamber walls. Aggressive mechanical circulatory support may be an essential bridge for recovery or even transplantation in patients with fulminant myocarditis with shock.
Graphical Abstract
相似文献32.
Tannistha Nandi Matthew T.G. Holden Xavier Didelot Kurosh Mehershahi Justin A. Boddey Ifor Beacham Ian Peak John Harting Primo Baybayan Yan Guo Susana Wang Lee Chee How Bernice Sim Angela Essex-Lopresti Mitali Sarkar-Tyson Michelle Nelson Sophie Smither Catherine Ong Lay Tin Aw Chua Hui Hoon Stephen Michell David J. Studholme Richard Titball Swaine L. Chen Julian Parkhill Patrick Tan 《Genome research》2015,25(1):129-141
Burkholderia pseudomallei (Bp) is the causative agent of the infectious disease melioidosis. To investigate population diversity, recombination, and horizontal gene transfer in closely related Bp isolates, we performed whole-genome sequencing (WGS) on 106 clinical, animal, and environmental strains from a restricted Asian locale. Whole-genome phylogenies resolved multiple genomic clades of Bp, largely congruent with multilocus sequence typing (MLST). We discovered widespread recombination in the Bp core genome, involving hundreds of regions associated with multiple haplotypes. Highly recombinant regions exhibited functional enrichments that may contribute to virulence. We observed clade-specific patterns of recombination and accessory gene exchange, and provide evidence that this is likely due to ongoing recombination between clade members. Reciprocally, interclade exchanges were rarely observed, suggesting mechanisms restricting gene flow between clades. Interrogation of accessory elements revealed that each clade harbored a distinct complement of restriction-modification (RM) systems, predicted to cause clade-specific patterns of DNA methylation. Using methylome sequencing, we confirmed that representative strains from separate clades indeed exhibit distinct methylation profiles. Finally, using an E. coli system, we demonstrate that Bp RM systems can inhibit uptake of non-self DNA. Our data suggest that RM systems borne on mobile elements, besides preventing foreign DNA invasion, may also contribute to limiting exchanges of genetic material between individuals of the same species. Genomic clades may thus represent functional units of genetic isolation in Bp, modulating intraspecies genetic diversity.Burkholderia pseudomallei (Bp) is the causative agent of melioidosis, a serious infectious disease of humans and animals and a leading cause of community-acquired sepsis and pneumonia in endemic regions (Currie et al. 2010). Initially thought to be confined to Southeast Asia and Northern Australia, the prevalence of Bp appears to be spreading (Wiersinga et al. 2012), and Bp has been designated a biothreat select agent in the United States. Bp can persist in extreme environmental conditions and can infect several plant and animal hosts, including birds, dolphins, and humans (Wuthiekanun et al. 1995; Howard and Inglis 2003; Sprague and Neubauer 2004; Larsen et al. 2013). Treatment of clinical melioidosis is challenging because the bacterium is inherently resistant to many antibiotics, and Bp infections can persist in humans for more than a decade (Hayden et al. 2012; Wiersinga et al. 2012).The Bp genome comprises one of the largest and most complex bacterial genomes sequenced to date. Consisting of two large circular replicons (chromosomes) with a combined 7.2-Mb genome size (Holden et al. 2004), it contains a rich arsenal of genes related to virulence (e.g., Type III and Type VI secretion systems, polysaccharide biosynthesis clusters), metabolic pathways, and environmental adaptation (Wiersinga et al. 2012). Besides conserved regions, accessory genes on mobile elements and genomic islands may also contribute to phenotypic and clinical differences in microbial behavior (Currie et al. 2000; Sim et al. 2008). Analysis of the Bp genome has revealed previously unknown toxins and mechanisms of antibiotic resistance (Chantratita et al. 2011; Cruz-Migoni et al. 2011).Most large-scale studies of Bp genetic diversity to date have analyzed strains using multilocus sequence typing (MLST). These studies have suggested a high degree of genetic variability between Bp strains and related Burkholderia species (Cheng et al. 2008), and have shown that Bp strains belonging to different sequence types (STs) can often coexist in the same locale and sometimes even within the same sample (Pitt et al. 2007; Wuthiekanun et al. 2009). However, due to the limited number of genes analyzed by MLST, these studies cannot comment on the global proportion of genetic material shared between strains of different STs nor on the relative contribution of recombination, mutation, and horizontal gene transfer on intraspecies genetic diversity. Moreover, although previous studies have applied whole-genome sequencing (WGS) to study global patterns of Bp genetic heterogeneity and evolution, earlier Bp WGS reports have been confined to a limited number of isolates (10–12) derived from diverse geographical regions (Nandi et al. 2010), where geophysical barriers likely limit the propensity of the analyzed strains to exchange genetic material. To achieve a comprehensive understanding of genetic variation among closely related Bp strains, WGS analysis of much larger strain panels, ideally performed on strains isolated from a common region and belonging to the same (or closely related) ST groups, is required.In this study, we attempted to fill this important knowledge gap by performing WGS on 106 Bp strains drawn from a restricted Asian locale (Singapore and Malaysia). The WGS data, exceeding previous Bp WGS studies by 10-fold, enabled us to identify specific genomic clades of Bp, molecular features of Bp recombination at the whole-genome level, and accessory genome features contributing to recombination and horizontal gene transfer. We found a consistent pattern of genetic separation correlating with MLST, recombination haplotypes, shared accessory genes, and restriction modification (RM) systems. We provide evidence that restriction modification, beyond its role as defense against foreign DNA invasion, may have also partitioned the Bp species by restricting gene flow, resulting in the other observed correlations. Because RM systems are widely dispersed through the bacterial kingdom, it is possible that similar principles may apply to other bacterial species, implicating a potential role for epigenetic barriers as a driver of early incipient speciation. 相似文献
33.
Duraid Younan Chee Paul Lin Robert Johnson Robert Clark Lisa Smith Jean-Francois Pittet Mali Mathru David W. Miller 《The American journal of emergency medicine》2018,36(8):1439-1443
Background
Little data is available in the literature about the role of end tidal oxygen in critically ill patients. We sought to identify the association between the level of respiratory oxygen and clinical outcomes in critically-ill ventilated trauma and burn patients.Methods
A retrospective cohort of 55 trauma and burn patients from 2010 to 2016 was collected. Exposures of interest included a) expiratory end tidal oxygen (ETO2) and b) the difference between FiO2 and ETO2 (uptake). Associations of clinical characteristics with ETO2 and oxygen uptake were examined using a Spearman correlation. The relationships between discharge status, demographics, injury type, severity, and clinical characteristics were examined using chi-square (or Fisher's exact) tests and two-sample t-tests. Multivariable analyses using linear and logistic regression were performed to determine whether expiratory end tidal oxygen or oxygen uptake was an independent predictor of clinical outcomes.Results
Mean age for the patients was 46.3 ± 18.2 years with 41 (74.6%) male and 34 (61.8%) white. In the cohort, 27 (49.1%) of patients had burns and 28 (50.9%) blunt trauma. Oxygen uptake was negatively correlated with lactic acid, minute ventilation, total ICU days, and ventilator days (p < 0.05). Patients who died demonstrated lower oxygen uptake than those alive, oxygen uptake remained significantly associated with discharge status after adjusting for potential confounders (p = 0.028).Conclusion
A narrowed difference between ETO2 and inspiratory oxygen is associated with increased mortality in a cohort of ventilated trauma and burn patients. Future research is needed to further elucidate the role of respiratory oxygen level in larger, prospective studies. 相似文献34.
Fara Wahida Rezali Yit Siew Chin Zalilah Mohd Shariff Barakatun Nisak Mohd Yusof Kaartina Sanker Fui Chee Woon 《Nutrition Research And Practice》2015,9(5):511-516
BACKGROUND/OBJECTIVES
This study aims to determine contribution of meal frequency, self-efficacy for healthy eating, and availability of healthy foods towards diet quality of adolescents in Kuala Lumpur, Malaysia.SUBJECTS/METHODS
This study was conducted among 373 adolescents aged from 13 to 16 years old. Diet quality of the respondents was assessed using the Healthy Eating Index for Malaysians. Meal frequency, self-efficacy for healthy eating, and availability of healthy foods were assessed through the Eating Behaviours Questionnaire (EBQ), self-efficacy for healthy eating scale, and availability of healthy foods scale, respectively.RESULTS
The majority of the respondents (80.7%) were at risk of poor diet quality. Males (mean = 34.2 ± 8.2%) had poorer diet quality than females (mean = 39.9 ± 9.0%) (t = -5.941, P < 0.05). Malay respondents (mean = 36.9 ± 8.7%) had poorer diet quality than Indian respondents (mean = 41.3 ± 10.0%) (F = 2.762, P < 0.05). Age (r = 0.123, P < 0.05), self-efficacy for healthy eating (r = 0.129, P < 0.05), and availability of healthy foods (r = 0.159, P < 0.05) were positively correlated with the diet quality of the respondents. However, meal frequency was not correlated with the diet quality of the respondents. Multiple linear regression analysis showed that being a male, being a Malay, low self-efficacy for healthy eating, and low availability of healthy foods contributed significantly towards poor diet quality among respondents.CONCLUSIONS
In short, sex, ethnicity, self-efficacy for healthy eating, and availability of healthy foods were associated with diet quality among adolescents. Health practitioners should take into consideration of differences in sex and ethnicity during implementation of nutrition-related intervention programs. Self-efficacy for healthy eating and availability of healthy foods should be included as important components in improving diet quality of adolescents. 相似文献35.
36.
The aim of this study was to examine optimal self-management in osteoarthritis and its association with patient-reported outcomes.
We recruited a population-based sample of Medicare beneficiaries (n = 551) residing in Allegheny County, PA, USA and elicited an expanded set of self-management behaviors using open-ended inquiry.
We defined optimal self-management according to clinical recommendations, including use of hot compresses on affected joints,
alteration of activity, and exercise. Only 20% practiced optimal self-management as defined by two or more of these criteria.
Optimal and suboptimal self-managers did not differ in sociodemographic features. Both white and African–Americans who practiced
optimal self-management reported significantly less pain, but the benefit was greatest in severe disease for whites and for
mild-moderate disease among African–Americans. This backdrop of naturally occurring self-management behaviors may be important
to recognize in planning programs that seek to bolster self-management skills. 相似文献
37.
Jain M Brenner DA Cui L Lim CC Wang B Pimentel DR Koh S Sawyer DB Leopold JA Handy DE Loscalzo J Apstein CS Liao R 《Circulation research》2003,93(2):e9-16
Reactive oxygen species (ROS)-mediated cell injury contributes to the pathophysiology of cardiovascular disease and myocardial dysfunction. Protection against ROS requires maintenance of endogenous thiol pools, most importantly, reduced glutathione (GSH), by NADPH. In cardiomyocytes, GSH resides in two separate cellular compartments: the mitochondria and cytosol. Although mitochondrial GSH is maintained largely by transhydrogenase and isocitrate dehydrogenase, the mechanisms responsible for sustaining cytosolic GSH remain unclear. Glucose-6-phosphate dehydrogenase (G6PD) functions as the first and rate-limiting enzyme in the pentose phosphate pathway, responsible for the generation of NADPH in a reaction coupled to the de novo production of cellular ribose. We hypothesized that G6PD is required to maintain cytosolic GSH levels and protect against ROS injury in cardiomyocytes. We found that in adult cardiomyocytes, G6PD activity is rapidly increased in response to cellular oxidative stress, with translocation of G6PD to the cell membrane. Furthermore, inhibition of G6PD depletes cytosolic GSH levels and subsequently results in cardiomyocyte contractile dysfunction through dysregulation of calcium homeostasis. Cardiomyocyte dysfunction was reversed through treatment with either a thiol-repleting agent (L-2-oxothiazolidine-4-carboxylic acid) or antioxidant treatment (Eukarion-134), but not with exogenous ribose. Finally, in a murine model of G6PD deficiency, we demonstrate the development of in vivo adverse structural remodeling and impaired contractile function over time. We, therefore, conclude that G6PD is a critical cytosolic antioxidant enzyme, essential for maintenance of cytosolic redox status in adult cardiomyocytes. Deficiency of G6PD may contribute to cardiac dysfunction through increased susceptibility to free radical injury and impairment of intracellular calcium transport. The full text of this article is available online at http://www.circresaha.org. 相似文献
38.
Estri Arthaningtyas Chee Choy Kok Viatcheslav A. Mordvinov Colin J. Sanderson 《Growth factors (Chur, Switzerland)》2013,31(3):211-221
The role of eosinophilia in allergic disorders indicates hIL-5 as a potential target for therapy. The conservation of hIL-5 gene proximal elements suggests they are important in controlling expression. Corticosteroids are important in the treatment of allergy, and are powerful inhibitors of IL-5 expression. This study aimed at understanding the role of hIL-5 conserved proximal elements, and elucidating the target of corticosteroid activity, in hIL-5 gene expression. Methods used include transient transfection of PBMC and PER117 cells with hIL-5 deletion constructs, EMSA, Western Blotting, and RT-PCR.The conserved proximal CLE0/TATA elements driving a reporter gene gave similar or higher expression than a 500 bp promoter in primary human T cells and a T-cell line. Two and three copies of IL-5 CLE0 upstream of the silent IL-4 minimal promoter gave 30–45 fold increases in expression in forward orientation, but little activity in reverse orientation. Consequently, CLE0 is a powerful activator but not a classical enhancer. Deletion analysis identified CLE0 as the key element in the inhibition of IL-5 reporter constructs by dexamethasone, and RT-PCR analysis indicated that GILZ expression correlated with dexamethasone-induced inhibition of IL-5. Ectopic expression of GILZ, confirmed by western blotting, gave a 90% inhibition of promoter constructs in absence of dexamethasone. CLE0 is a powerful activator sufficient for the inducible expression of IL-5, and functions when moved upstream in a heterologous promoter. CLE0 is also the main target for IL-5 inhibition by dexamethasone, and we present evidence consistent with a role of GILZ in this. 相似文献
39.
40.
Wee Chee Tan Indu Bala Jaganath Rishya Manikam Shamala Devi Sekaran 《International journal of medical sciences》2013,10(13):1817-1829
Nucleoside analogues such as acyclovir are effective antiviral drugs against herpes simplex virus infections since its introduction. However, with the emergence of acyclovir-resistant HSV strains particularly in immunocompromised patients, there is a need to develop an alternative antiherpetic drug and plants could be the potential lead. In this study, the antiviral activity of the aqueous extract of four Phyllanthus species were evaluated against herpes simplex virus type-1 (HSV-1) and HSV-2 in Vero cells by quantitative PCR. The protein expressions of untreated and treated infected Vero cells were studied by 2D-gel electrophoresis and Western blot. This is the first study that reported the antiviral activity of P. watsonii. P. urinaria was shown to demonstrate the strongest antiviral activity against HSV-1 and HSV-2, with SI >33.6. Time-of-addition studies suggested that the extract may act against the early infection stage and the replication stage. Protein expression studies indicated that cellular proteins that are involved in maintaining cytoskeletal structure could be potential target for development of antiviral drugs. Preliminary findings indicated that P. urinaria demonstrated potent inhibitory activity against HSV. Hence, further studies such as in vivo evaluation are required for the development of effective antiherpetic drug. 相似文献