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During embryogenesis, the mammalian heart develops from a primitive heart tube originating from two bilateral primary heart fields located in the lateral plate mesoderm. Cells belongings to the pre-cardiac mesoderm will differentiate into early cardiac progenitors, which express early transcription factors which are also common to the Isl-1 positive cardiac progenitor cells isolated from the developing pharyngeal mesoderm and the foetal and post-natal mice hearts. A second population of cardiac progenitor cells positive to c-Kit has been abundantly isolated from adult hearts. Until now, these two populations have been considered two different sets of progenitor cells present in the heart in different stages of an individual life. In the present study we collected embryonic, foetal and infant hearts, and we tested the hypotheses that c-Kit positive cells, usually isolated from the adult heart, are also present in the intra-uterine life and persist in the adult heart after birth, and that foetal Isl-1 positive cells are also positive to c-Kit. Using immunohistochemistry we studied the temporal distribution of Isl-1 positive and c-Kit/CD105 double positive cells, and by immunofluorescence and confocal analysis we studied the co-localization of c-Kit and Isl-1 positive cells. The results indicated that cardiomyocytes and interstitial cells were positive for c-Kit from the 9th to the 19th gestational week, that cells positive for both c-Kit and CD105 appeared in the interstitium at the 17th gestational week and persisted in the postnatal age, and that the Isl-1 positive cells were a subset of the c-Kit positive population.

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We consider the three-body Casimir-Polder interaction between three atoms during their dynamical self-dressing. We show that the time-dependent three-body Casimir-Polder interaction energy displays nonlocal features related to quantum properties of the electromagnetic field and to the nonlocality of spatial field correlations. We discuss the measurability of this intriguing phenomenon and its relation with the usual concept of stationary three-body forces.

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BACKGROUND AND AIM: Thyroid pathologies, in particular goiter, are commonly found in everyday clinical practice in hospitalised patients. METHODS: The authors carried out a prospective type survey lasting 80 months in a mountain community with about 30,000 inhabitants with uniform socio-demographical characteristics. A total of 8,034 subjects (4,131 males and 3,903 females) were included in the study who were hospitalised in an Internal Medicine Department. All patients underwent screening using standard diagnostic criteria. RESULTS: Thyroid pathology was identified and classified into its various forms. There was a net prevalence of goiter which, owing to the unique features identified by the study, was defined as the sporadic form. The study demonstrated a marked prevalence in females, the familial pattern, the homogeneity of distribution throughout the area, the progression of disease with age and its evolution into immersed forms, the prevalence in both sexes in adults, the frequent use of surgery and its inherent problems, the inadequacy of treatment. CONCLUSIONS: The authors affirm that this pathology is regularly underestimated because it is not adequately identified, treated and monitored. They suggest a clinical and methodological approach based on a correct nosological definition, adequate diagnostic and prognostic stratification, an appropriate therapeutic protocol and clinical controls performed over time.

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The Holothuria polii Polian vesicles are organs of inflammatory responsiveness. Under antigenic provocation, they respond with remarkable structural modifications. They are also able to produce brown bodies that represent a survival strategy, used by the holothuroid, to rid the body of non-self material presented to it.

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