4,609 research outputs found

    Intramyocardial hemorrhage: An enigma for cardiac MRI?

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    Cardiovascular magnetic resonance (CMR) is a useful noninvasive technique for determining the presence of microvascular obstruction (MVO) and intramyocardial hemorrhage (IMH), frequently occurring in patients after reperfused myocardial infarction (MI). MVO, or the so-called no-reflow phenomenon, is associated with adverse ventricular remodeling and a poor prognosis during follow-up. Similarly, IMH is considered a severe damage after revascularization by percutaneous primary coronary intervention (PPCI) or fibrinolysis, which represents a worse prognosis. However, the pathophysiology of IMH is not fully understood and imaging modalities might help to better understand that phenomenon. While, during the past decade, several studies examined the distribution patterns of late gadolinium enhancement with different CMR sequences, the standardized CMR protocol for assessment of IMH is not yet well established. The aim of this review is to evaluate the available literature on this issue, with particular regard to CMR sequences. New techniques, such as positron emission tomography/magnetic resonance imaging (PET/MRI), could be useful tools to explore molecular mechanisms of the myocardial infarction healing process

    The Status of the United States Population of Night Shark, Carcharhinus signatus

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    Night sharks, Carcharhinus signatus, are an oceanic species generally occurring in outer continental shelf waters in the western North Atlantic Ocean including the Caribbean Sea and Gulf of Mexico. Although not targeted, night sharks make up a segment of the shark bycatch in the pelagic longline fishery. Historically, night sharks comprised a significant proportion of the artisanal Cuban shark fishery but today they are rarely caught. Although information from some fisheries has shown a decline in catches of night sharks, it is unclear whether this decline is due to changes in fishing tactics, market, or species identification. Despite the uncertainty in the decline, the night shark is currently listed as a species of concern due to alleged declines in abundance resulting from fishing effort, i.e. overutilization. To assess their relevance to the species of concern list, we collated available information on the night shark to provide an analysis of its status. Night shark landings were likely both over- and under-reported and thus probably did not reflect all commercial and recreational catches, and overall they have limited relevance to the current status of the species. Average size information has not changed considerably since the 1980’s based on information from the pelagic longline fishery when corrected for gear bias. Analysis of biological information indicates night sharks have intrinsic rates of increase (r) about 10% yr–1 and have moderate rebound potential and an intermediate generation time compared to other sharks. An analysis of trends in relative abundance from four data sources gave conflicting results, with one series in decline, two series increasing, and one series relatively flat. Based on the analysis of all currently available information, we believe the night shark does not qualify as a species of concern but should be retained on the prohibited species list as a precautionary approach to management until a more comprehensive stock assessment can be conducted

    Early detection of biochemically occult autonomous thyroid nodules

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    Objective: Autonomously functioning thyroid areas may be associated with subclinical or overt hyperthyroidism, but may exist even in the presence of normal TSH. This study was aimed at comparing the rate of autonomously functioning areas and their cardiac sequelae in patients with nodular goitre studied with the usual and a novel approach. Design and methods: In total 490 adult outpatients with thyroid nodular goitre, living in a mild iodine-deficient area, were selected in our referral centre for thyroid diseases from 2009 to 2014 on the basis of a suspicion of thyroid functional autonomy. They were divided in three groups according to a non-conventional approach (excessive response to thyroxine treatment: group 1) or conventional approach (low/normal TSH with clinical suspicion or low TSH: groups 2 and 3). All patients of the study with the suspicion of thyroid functional autonomy underwent thyroid scan with radioactive iodine (I131) uptake (RAIU). Results: The percentage of confirmed thyroid functional autonomy was 319/490, being significantly higher in group 3 than in groups 1 and 2 (81.5 vs 64.7 vs 52.6%; chi-square P < 0.0001). However, the diagnosis with non-conventional approach was made at a significant earlier age (P < 0.0001). Cardiac arrhythmias as well as atrial fibrillation were similarly detected by conventional and non-conventional approaches (chi-square test: P = 0.2537; P = 0.8425). Conclusions: The hyper-responsiveness to thyroxine treatment should induce the suspicion of thyroid functional autonomy at an early stage, allowing to detect autonomous functioning areas in apparently euthyroid patients

    Effects of a Three-day Period of Intense, Intermittent Exercise on Oxidative Stress and Inflammation

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    It is documented that strenuous and prolonged exercise induces oxidative stress and inflammation, with the associated muscle damage and fatigue compromising performance. Little is known about the oxidant effects of intense, intermittent exercise, as performed daily by elite athletes competing in team sports. PURPOSE: To assess the short-term effects of a 3-day period of intense, intermittent exercise on biomarkers of oxidative stress and inflammation in trained athletes. METHODS: Ten trained athletes (age: 32.11±1.91yrs; mass: 66.33±1.95kg; maximal oxygen uptake (VO2max): 51.44±1.59mL·kg·minˉ1) completed a high-intensity, intermittent exercise protocol (90-minute intermittent treadmill run, ~70% VO2max) on three consecutive days and were compared to a control group (N=10). Blood samples were collected immediately pre (T1) and post (T2) the 3-day exercise protocol, then 21h- (T3) and 42h-post-exercise (T4); and assayed for Total Antioxidant Status (TAS), Thiobarbituric Acid Reactive Substances (TBARS), Interleukins (IL-6, IL-8 and IL-10), C-Reactive Protein (C-RP) and Lactate Dehydrogenase (LDH). Data were corrected for plasma volume change; results presented as M±SE. RESULTS: No significant differences were observed between the exercise and control group at T1 (TAS: 1.20±0.14mmol.L-1 vs. 1.18±0.11mmol.L-1; LDH: 302.14±16.24U/L vs. 295.27±31.26U/L; TBARS: 6.21±1.09μM vs. 5.88±1.00μM; and IL-6: 0.67±0.70pg/ml vs. 1.12±0.28pg/ml). The 3-day exercise period caused a significant increase in LDH (413.24±35.27U/L, P = 0.029), IL-6 (2.54±0.35pg/ml, P = 0.037) and TBARS (7.00±0.61μM, P = 0.042) at T2, with the effects of TBARS remaining above baseline at T4 (6.43±0.79μM, P = 0.043). TAS increased post-exercise with a significant difference observed between groups at T2 (1.86±0.21mmol.L-1 vs. 1.20±0.13mmol.L-1, P = 0.006), T3 (1.86±0.28mmol.L-1 vs. 1.30±0.14mmol.L-1, P = 0.010) and T4 (1.71±0.22mmol.L-1 vs. 1.17±0.13mmol.L-1, P = 0.014). IL-8, IL-10, and C-RP did not differ between groups. CONCLUSIONS: A 3-day period of intense, intermittent exercise increased oxidative stress and upregulated antioxidants in trained athletes, confirming the current model that exercise-induced oxidants play an important role in intracellular signaling pathways of endogenous antioxidants

    Emotional experiences in youth tennis

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    Abstract Objectives To explore adolescents' emotional experiences in competitive sport. Specifically, this study sought to identify, 1) The emotions adolescents' experience at tennis tournaments, 2) The precursors of the emotions they experience, and, 3) How adolescents attempt to cope with these emotions. Design Case-study. Method Four adolescent tennis players competed in four or five tennis matches under the observation of a researcher. Immediately following each match, participants completed a post-match review sheet and a semi-structured interview. A further semi-structured interview was completed at the end of the tournament. Review sheets, notes from match observations, and video recordings of matches were used to stimulate discussions during final interviews. All data were analyzed following the procedures outlined by Miles and Huberman (1994). Results Participants cited numerous positively and negatively valenced emotions during matches and tournaments. Participants' emotions seemed to be broadly influenced by their perceptions of performance and outcomes, as well as their opponent's behavior and player's perceptions of their own behavior. Participants described various strategies to cope with these emotions, such as controlling breathing rate, focusing on positive thoughts, and individualized routines. Further, if participants perceived them to be facilitative, negative emotions could be beneficial for performance. Conclusion This study provided original insights into the complexity of adolescent athletes' emotional experiences at competitions and highlights the critical need for further in-depth examinations of youth sport to fully comprehend the experiences of young people. Most notably, the findings highlight the necessity of considering the impact of both intra- and interpersonal influences on adolescents' emotional experiences, while also accounting for temporal changes

    Automated, high accuracy classification of Parkinsonian disorders: a pattern recognition approach

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    Progressive supranuclear palsy (PSP), multiple system atrophy (MSA) and idiopathic Parkinson’s disease (IPD) can be clinically indistinguishable, especially in the early stages, despite distinct patterns of molecular pathology. Structural neuroimaging holds promise for providing objective biomarkers for discriminating these diseases at the single subject level but all studies to date have reported incomplete separation of disease groups. In this study, we employed multi-class pattern recognition to assess the value of anatomical patterns derived from a widely available structural neuroimaging sequence for automated classification of these disorders. To achieve this, 17 patients with PSP, 14 with IPD and 19 with MSA were scanned using structural MRI along with 19 healthy controls (HCs). An advanced probabilistic pattern recognition approach was employed to evaluate the diagnostic value of several pre-defined anatomical patterns for discriminating the disorders, including: (i) a subcortical motor network; (ii) each of its component regions and (iii) the whole brain. All disease groups could be discriminated simultaneously with high accuracy using the subcortical motor network. The region providing the most accurate predictions overall was the midbrain/brainstem, which discriminated all disease groups from one another and from HCs. The subcortical network also produced more accurate predictions than the whole brain and all of its constituent regions. PSP was accurately predicted from the midbrain/brainstem, cerebellum and all basal ganglia compartments; MSA from the midbrain/brainstem and cerebellum and IPD from the midbrain/brainstem only. This study demonstrates that automated analysis of structural MRI can accurately predict diagnosis in individual patients with Parkinsonian disorders, and identifies distinct patterns of regional atrophy particularly useful for this process

    The impact of early life immune challenge on behavior and microglia during postnatal development

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    Sexual dichotomy exists in the development, presentation, and course of many neuropsychiatric disorders, including anxiety. Anxiety disorders are one of the earliest psychiatric illnesses to manifest and a role for immune system programming of the developing CNS has emerged in relation to anxiety. Adult rodents neonatally exposed to an immune challenge exhibit increased anxiety-related behaviors. The objective of this study was to determine the impact of postnatal immune challenge on behavior and microglia during the postnatal period and in adulthood. Mice were administered lipopolysaccharide (LPS; 0.05mg/kg, i.p.) or saline on postnatal days (P) three and five. Anxiety-related behavior was assessed during early development on P15 and P21, and re-assessed in adulthood at 10 and 12 weeks. Results reveal sex-specificity in the temporal emergence and phenotypic profile of behaviors displayed by LPS-treated mice. Male LPS-treated mice exhibited reduced exploratory in early development (P15 and P21) that persisted into adulthood. Female LPS-mice exhibited increased anxiety-like behaviors in the EPM in adulthood. These results demonstrate a role for interactions between sex and the immune system in shaping the developmental trajectory of exploratory and anxiety-like behaviors
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