101,929 research outputs found
Experimental animal models of myocardinal damage in regenerative medicine studies involving adult bone marrow derived stem cells: ethical and methodological implication
No full textCardiac performance after myocardial infarction is compromised by ventricular remodeling, which represents a major cause of late infarct-related chronic heart failure and death. In recent years, the scientists' interest has focused on the hypothesis that the administration of bone marrow progenitors, following myocardial infarction, could ameliorate left ventricular remodeling by continuing to differentiate along the haematopoietic lineage. This approach has been developed minding to the consolidated use of transfusions to restore lost or depleted blood components and, therefore, as an enriched dose of various progenitors, generally autologous, injected peripherally or directly in the infarcted area. Since the safety of this therapy was not yet established, for ethical reasons pioneering researchers involved in these studies used animal models as surrogate of the human biologic system. Herein this hypothesis of therapy resulted in an increased use of living animals and in the reappraisal of models of myocardial damage with limited discussion on the theoretical basis of animal models applied to cell-based therapies. Recently, the European Union and its commission for surveillance of laboratory animals advanced a new proposal to restrict the use of living animals. This review will focus on the history of models utilization in biomedicine, with particular attention to animal models, and delineate an operative comparison between the two best known models of myocardial injury, namely coronary ligation and cryodamage, in the perspective of adult stem cell research applied to cardiovascular regenerative medicine
Imaging of tangential traction types in lamellar macular holes
No full textPURPOSE:
To determine the best imaging procedure for the definition of tangential tractions generated by epiretinal membranes in lamellar macular holes.
METHODS:
Inclusion criteria were a diagnosis of lamellar macular hole with tractional epiretinal membranes based upon fundus autofluorescence (FAF), and spectral-domain optical coherence tomography (SD-OCT) imaging (HRA + OCT Spectralis, Heidelberg Engineering, Heidelberg, Germany). Tangential tractions were evaluated with infrared reflectance (IR; 820 nm) and OCT en face (193 B-scans, 30 × 20°pattern size, 31 μm between two consecutive B-scans). Three different categories of tangential traction were previously defined: 1) unidirectional, 2) pluridirectional, and 3) concentric. Two independent masked physicians evaluated the images in order to categorize the type of tangential traction either with IR and OCT (en face) for every single patient. Cohen's kappa statistic was used to evaluate inter-observer and inter-instrument agreement.
RESULTS:
Twenty eyes of 19 patients were included in the study. Inter-observer OCT test showed almost perfect agreement between examiners (κ = 0.86). Inter-observer IR test showed substantial agreement (κ = 0.7). Inter-instrument agreement was fair for both observers, respectively κ = 0.35 for observer 1 and κ = 0.22 for observer 2. Intra-observer agreement was almost perfect for OCT (κ = 0.93) and substantial for IR (κ = 0.78).
CONCLUSION:
Tangential traction associated with epiretinal membranes in lamellar macular holes can be successfully evaluated by OCT en face and IR reflectance. Inter-observer concordance is high for both instruments. However, high inter-instrument discordance is present. Therefore, the gold standard imaging technique for differentiating the different types of contraction in epiretinal membranes has still to be determined
The strict Positivstellensatz for global analytic functions and the moment problem for semianalytic sets
No full textAnalytic functions strictly positive on a global semianalytic set X = {f1 0, · · · , fk 0} in Rn
are characterized as functions expressible as g = a0+a1f1+· · ·+akfk for strictly positive global analytic functions a0, · · · , ak. The proof is elementary, using the fact that the analytic functions are dense in C(Rn,R) in the Whitney topology. The same proof works for Nash functions. This is an improvement of the standard analytic version of Stengle’s Positivstellensatz in two directions: The hypothesis is weaker (there is no requirement that X be compact) and the conclusion is stronger. Several applications are given including: (i) a new proof of the weak Positivstellensatz for semianalytic sets; and (ii) the solution of theK-moment problem for basic closed semianalyticGNSAGACNRMURSTDGESDepto. de Álgebra, Geometría y TopologíaFac. de Ciencias MatemáticasTRUEpu
Episodes of Fall Asleep During Day Time in an Elder Woman with Vascular Dementia : Impact on Cerebral Ischeamic Tolerance and Utility of ECG Holter Monitoring
No full textHere we report the case of an 86-year-old woman with advanced dementia addressed to our service for routinary ECG Holter Monitoring (EHM) for bradycardia in AV block type I. Several day-time episodes of fall-asleep while sitting had been previously reported by the nurse and generally attributed to the dementia itself, without taking into consideration the hypothesis of an AV block. The EHM reading reported several and often subsequent pauses (561), many of them critical, the longest lasting 15,9 s with no changes in clinical condition of the patient. The results of the EHM were reported to the physicians in charge for the patient and subsequently the woman was referred to the arrhythmology unit for pace-maker device implantation. Generalizing our experience, we suggest that advanced dementia, often associated with episodes of fall-asleep, could mask a conduction disturbance causing critical pauses with syncope; therefore we suggest screening those patients for possible arrhythmic disorders. Finally, we remark that in our patient the pauses weren't associated with a worsening of the patient as seen in the follow-up, and this fact supports the hypothesis that vascular dementia could increase cerebral ischaemic tolerance
La tossina botulinica nel recupero del piede equino-valgo da paralisi cerebrale infantile
No full textThe different role of sex hormones on female cardiovascular physiology and function: not only oestrogens
No full textHuman response to different physiologic stimuli and cardiovascular (CV) adaptation to various pathologies seem to be gender specific. Sex-steroid hormones have been postulated as the major contributors towards these sex-related differences. This review will discuss current evidence on gender differences in CV function and remodelling, and will present the different role of the principal sex-steroid hormones on female heart. Starting from a review of sex hormones synthesis, receptors and CV signalling, we will summarize the current knowledge concerning the role of sex hormones on the regulation of our daily activities throughout the life, via the modulation of autonomic nervous system, excitation-contraction coupling pathway and ion channels activity. Many unresolved questions remain even if oestrogen effects on myocardial remodelling and function have been extensively studied. So this work will focus attention also on the controversial and complex relationship existing between androgens, progesterone and female hear
Dark Atrophy: An Optical Coherence Tomography Angiography Study.
No full textPURPOSE: To assess the status of choriocapillaris in eyes with macular atrophy secondary to age-related macular degeneration (AMD) (geographic atrophy [GA]) and Stargardt disease (STGD) using optical coherence tomography angiography (OCTA).
DESIGN:
Prospective, observational case series.
PARTICIPANTS:
A total of 14 patients (20 eyes) affected by GA and 10 patients (20 eyes) affected by STGD.
METHODS:
Each patient underwent a complete ophthalmological examination including fundus autofluorescence (FAF), dynamic simultaneous fluorescein angiography (FA) and indocyanine green angiography (ICGA), enhanced-depth imaging optical coherence tomography (EDI-OCT) (HRA+OCT Spectralis, Heidelberg Engineering, Heidelberg, Germany), and OCTA using AngioVue technologies (Optovue Inc, Freemont, CA).
MAIN OUTCOME MEASURES:
An evaluation of the status of choriocapillaris in the 2 groups was performed.
RESULTS:
Patients' mean age was 75 years for subjects with GA (median, 76 years; range, 63-88 years) and 61 years for STGD (median, 62 years; range, 40-74 years). Atrophy was bilateral in 42% (n = 6) of subjects with GA and 100% (n = 10) of subjects with STGD. In the early frames, FA displayed hyperfluorescence in the atrophic area in 100% (n = 20) of eyes affected by GA and 20% (n = 4) of eyes affected by STGD; dark choroid was present in 0% of GA eyes and 65% of STGD eyes (n = 13). Atrophy in ICGA late frames was hypofluorescent in 20% (n = 4) of GA eyes and 100% (n = 20) of STGD eyes. A ring at atrophy margins was detected in both FA (90%, n = 18) and ICGA (100%, n = 20) in STGD eyes. Mean subfoveal choroidal thickness was 156 μm (147, 42-362 μm) for GA eyes and 168 μm (167, 55-320 μm) for STGD eyes (P = 0.59). At OCTA evaluation, GA eyes showed persisting, rarefied choriocapillaris in correspondence of retinal pigment epithelium (RPE) atrophy in 80% (n = 16) of cases, whereas eyes affected by STGD had disappearance of this tissue in 100% (n = 20; P < 0.0001).
CONCLUSIONS:
Analysis of macular atrophy by OCTA in patients with STGD revealed an extensive loss of choriocapillaris in the central area with persisting tissue at its margins, whereas in those with GA the area of RPE loss showed persistent but rarefied choriocapillaris
Tempo di essere incivili : Una riflessione terrona sull'omonazionalismo in Italia al tempo dell'austerity
No full textLimited hypotensive effect of sildenafil in a high-risk population: a preliminary report
No full textErectile dysfunction (ED) is often associated with cardiovascular disease (CVD) and the risk of sildenafil-induced orthostatic hypotension (OH) in subjects with CVD is a matter of concern. We describe our experience in using the tilt test (TT) with continuous plethysmography to evaluate the occurrence of OH in patients with CVD and ED after a test dose of sildenafil. When sildenafil was added on top of their usual pharmacological treatment two patients out of 32 (6.2%) developed asymptomatic OH, with a maximum blood pressure fall of 40/20 mm Hg. The low prevalence and modest clinical relevance of OH in our high-risk population coupled with the known high sensitivity and reproducibility of the TT seem to suggest that sildenafil is haemodynamically safer than is generally believed even when added on top of vasoactive treatment. These findings should be put into perspective against the growing wealth of evidence that PDE5 inhibitors may have therapeutic potential for a number of CV conditions
Bibliographie Hilarion G. Petzold 1958 – 2009 mit Anhang als Einführung
No full textDieses Archiv enthält die Gesamtbibliographie der Werke des Autors nebst einiger Texte „Über H. G. Petzold“ im Schlussteil der Bibliographie sowie einen Anhang mit einer Einführung in die Architektur des Werkes in seinem wissenslogischen Aufbau als Ausarbeitung seines „Tree of Science Modells“ (2007).This archive contains the complete bibliography of the author and some texts about H. G. Petzold, moreover an epilogue with an introduction to the architecture of the works in its epistemological structure and composition and as an elaborations of Petzold’s „Tree of Science Modell (2007).https://www.fpi-publikation.de/polyloge/01-2009-petzold-h-g-gesamtbibliographie-h-g-petzold-1958-2009-updating-november2009/peerReviewedpublishedVersio
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