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Sacher  Robby  Wuttke  Marc  Knüdeler  Martin 《Manuelle Medizin》2019,57(2):100-102
Manuelle Medizin - Anhand der Beobachtung einer Manifestation des Proatlas mit Ausbildung eines zusätzlichen zervikalen Segments bei einem 8‑jährigen Jungen wird das Krankheitsbild...  相似文献   
63.
Interleukin-4 (IL-4) is a potent mediator of growth and differentiation of cells of several hematopoietic lineages. Interleukin-5 (IL-5) is a lineage-specific hematopoietic growth factor that stimulates the production of eosinophils and eosinophil colonies from normal human bone marrow cells. By using somatic cell hybrids and in situ chromosomal hybridization, we localized the IL-4 and IL-5 genes to human chromosome 5 at bands q23-31, a chromosomal region that is frequently deleted [del(5q)] in patients with myeloid disorders. By in situ hybridization, the IL-4 and IL-5 genes were found to be deleted in the 5q- chromosome of four patients with refractory anemia (RA) or therapy-related acute nonlymphocytic leukemia (t-ANLL), who had a del(5q). Thus a small segment of chromosome 5 contains IL-4, IL-5, IL- 3, and GM-CSF as well as other genes such as CD14 and EGR1. Our findings that each of these genes was deleted in the 5q- chromosome suggest that loss of function of one or more of these genes may play an important role in the pathogenesis of hematologic disorders associated with a del(5q).  相似文献   
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BACKGROUND: Areas of complex fractionated atrial electrograms (CFAEs) have been implicated in the atrial substrate of atrial fibrillation (AF). The mechanisms underlying CFAE in humans are not well investigated. OBJECTIVES: The purpose of this study was to investigate the regional activation pattern associated with CFAE using a high-density contact mapping catheter. METHODS: Twenty patients with paroxysmal AF were mapped using a high-density multielectrode catheter. CFAE were mapped at 10 different sites (left atrium [LA]: inferior, posterior, roof, septum, anterior, lateral; right atrium [RA]: anterior, lateral, posterior, septum). Local atrial fibrillation cycle length (AFCL) was measured immediately before and after the occurrence of CFAE, and the longest electrogram duration (CFAEmax) was assessed. RESULTS: Longer electrogram durations were recorded in the LA compared with the RA (CFAEmax 118 +/- 21 ms vs 104 +/- 23 ms, P = .001). AFCL significantly shortened before the occurrence of CFAEmax compared with baseline (LA: 174 +/- 32 ms vs 186 +/- 32 ms, P = .0001; RA: 177 +/- 31 ms vs 188 +/- 31 ms, P = .0001) and returned to baseline afterwards. AFCL shortened by >or=10 ms in 91% of mapped sites. Two different local activation patterns were associated with occurrence of CFAEmax: a nearly simultaneous activation in all spines in 84% indicating passive activation, and a nonsimultaneous activation sequence suggesting local complex activation or reentry. CONCLUSION: Fractionated atrial electrograms during AF demonstrate dynamic changes that are dependent on regional AFCL. Shortening of AFCL precedes the development of CFAE; thus, cycle length is a major determinant of fractionation during AF. High-density mapping in AF may help to differentiate passive activation of CFAE from CFAE associated with an active component of the AF process.  相似文献   
65.
We used light and electron microscopy to analyze the eyelid inflammation that develops in transgenic mice that overexpress interleukin-4 (IL-4; Tepper et al, Cell 62:457, 1990). Analysis of alkaline Giemsa-stained plastic sections examined by light microscopy (Dvorak et al, J Exp Med 132:558, 1970), as well as by routine transmission electron microscopy, indicated that the mast cells in the inflammatory eyelid lesions were undergoing piecemeal degranulation, a form of secretion in which the cells' cytoplasmic granules exhibit characteristic morphologic changes that are thought to be associated with the prolonged, vesicle-mediated release of the granules' constituents. Moreover, by using a newly reported enzyme affinity-gold method, which stains histamine based on binding to diamine oxidase-gold (Dvorak et al, J Histochem Cytochem 41:787, 1993), we show that these activated mast cells had released much of their histamine content. The eyelid lesions also exhibited increased numbers of mast cells; interstitial fibrosis, particularly around cutaneous nerves and blood vessels; activated fibroblasts; focal axonal damage; venules with endothelial cells containing numerous vesiculo-vacuolar organelles; and infiltrates of neutrophils and eosinophils. Our findings illustrate that overexpression of the IL-4 gene in vivo can result in eyelid lesions associated with piecemeal degranulation of mast cells, as well as tissue fibrosis and a variety of other pathologic changes. These results also represent the first direct morphologic evidence for histamine secretion by mast cells in vivo.  相似文献   
66.
The aim of this paper was to compare the recruitment strategies of two recent studies that focused on the parental influences on childhood obesity during the preschool years. The first study was a randomised controlled trial (RCT) of the Mind, Exercise, Nutrition?…?Do It! 2–4 obesity prevention programme and the second was a longitudinal cohort study. For both studies, the desired population were families with preschool children at risk of developing overweight or obesity. Hence, families from diverse ethnic and socio-economic backgrounds were sought. Funding for the RCT provided the resources to adopt a targeted approach to recruitment whereas for the longitudinal study, recruitment was random and opportunistic, rather than specific and targeted. The RCT reported higher child body mass index-for-age z scores, more families not from an Australian or New Zealand background, and more families in the lowest income bracket, suggesting that strategically targeted approaches to recruitment are more likely to achieve the desired sample.  相似文献   
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Background

The underlying mechanisms sustaining human persistent atrial fibrillation (PsAF) is poorly understood.

Objectives

This study sought to investigate the complexity and distribution of AF drivers in PsAF of varying durations.

Methods

Of 135 consecutive patients with PsAF, 105 patients referred for de novo ablation of PsAF were prospectively recruited. Patients were divided into 3 groups according to AF duration: PsAF presenting in sinus rhythm (AF induced), PsAF <12 months, and PsAF >12 months. Patients wore a 252-electrode vest for body surface mapping. Localized drivers (re-entrant or focal) were identified using phase-mapping algorithms.

Results

In this patient cohort, the most prominent re-entrant driver regions included the pulmonary vein (PV) regions and inferoposterior left atrial wall. Focal drivers were observed in 1 or both PV regions in 75% of patients. Comparing between the 3 groups, with longer AF duration AF complexity increased, reflected by increased number of re-entrant rotations (p < 0.05), number of re-entrant rotations and focal events (p < 0.05), and number of regions harboring re-entrant (p < 0.01) and focal (p < 0.05) drivers. With increased AF duration, a higher proportion of patients had multiple extra-PV driver regions, specifically in the inferoposterior left atrium (p < 0.01), superior right atrium (p < 0.05), and inferior right atrium (p < 0.05). Procedural AF termination was achieved in 70% of patients, but decreased with longer AF duration.

Conclusions

The complexity of AF drivers increases with prolonged AF duration. Re-entrant and focal drivers are predominantly located in the PV antral and adjacent regions. However, with longer AF duration, multiple drivers are distributed at extra-PV sites. AF termination rate declines as patients progress to longstanding PsAF, underscoring the importance of early intervention.  相似文献   
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