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Biomedical subjects

F Flora

Publications and source records attributed to F Flora.

5 recordsLinked to original sources

Analysis of high- n dielectronic Rydberg satellites in the spectra of Na -like Zn XX and Mg -like Zn XIX.

We have observed spectra from highly charged zinc ions in a variety of laser-produced plasmas. Spectral features that are Na - and Mg -like satellites to high- n Rydberg transitions in the Ne -like Zn XXI spectrum are analyzed and modeled. Identifications and analysis are made by comparison with highly accurate atomic structure calculations and steady state collisional-radiative models. Each observed Zn XX and Zn XIX feature comprises up to approximately 2 dozen individual transitions, these transitions are excited principally by dielectronic recombination through autoionizing levels in Na - and Mg -like Zn19+ and Zn18+. We find these satellites to be ubiquitous in laser-produced plasmas formed by lasers with pulse lengths that span four orders of magnitude, from 1 ps to approximately 10 ns. The diagnostic potential of these Rydberg satellite lines is demonstrated.

Journal Article↗

Comparative analysis of isolated cellular organelles by means of soft X-ray contact microscopy with laser-plasma source and transmission electron microscopy.

Soft X-ray contact microscopy (SXCM) is, at present, a useful tool for the examination at submicrometre resolution of biological systems maintained in their natural hydrated conditions. Among current X-ray-generating devices, laser-plasma sources are now easily available and, owing to their pulse nature, offer the opportunity to observe living biological samples before radiation damage occurs, even if the resolution achievable is not as high as with synchrotron-produced X-rays. To assess the potential of laser-plasma source SXCM in the study of cellular organelles, we applied it for the analysis of chloroplasts extracted from spinach leaves and mitochondria isolated from bovine heart and liver. X-ray radiation was generated by a nanosecond laser-plasma source, produced by a single shot excimer XeCl laser focused onto an yttrium target. The images obtained with SXCM were then compared with those produced by transmission electron microscopy observation of the same samples prepared with negative staining, a technique requiring no chemical fixation, in order to facilitate their interpretation and test the applicability of SXCM imaging.

Animals↗

Gershoni-Baruch syndrome: report of a new family confirming autosomal recessive inheritance.

Gershoni-Baruch syndrome is a multiple congenital malformation complex characterized by omphalocele, diaphragmatic hernia, cardiovascular abnormalities, and radial ray defects. Autosomal recessive inheritance is suggested. We describe two additional cases from a single family (sister and brother) delivered through termination at 23 and 9 weeks of gestation, respectively. The first fetus showed a spectrum of schisis defects without any limb involvement while the second bore mainly malformations of hands and feet. The occurrence of two different syndromes in the same family is highly improbable, but, considering both malformation complexes as possible manifestations of the same disease, a diagnosis of Gershoni-Baruch syndrome appears the most reasonable. These new familial cases bring further support to the hypothesis of an autosomal recessive inheritance of this syndrome.

Abnormalities, Multiple↗

Lithium fluoride as a novel X-ray image detector for biological mu-world capture.

X-ray microradiographs of small biological objects, such as animals and plant materials at micrometric resolution, are currently performed by various methods, all of which are limited by the resolution or the dynamic range of the image detectors. Here a novel X-ray image detector is discussed, in which the previous limitations have been overcome. A film of lithium fluoride salt is used as a detector, in which the stored biological image is read by observing the optically stimulated visible luminescence of the active color centers, efficiently produced by the X-rays.

Animals↗

[Multiple Spitz nevus].

Benign juvenile melanoma was originally described and differentiated from malignant melanoma by Sophie Spitz in 1948. The solitary form is the most frequent and usually appears on the face and extremities of young children and adolescents as a solitary, hairless, dome-shaped papule or nodule, varying in size from 3 to 15 mm. It can be of a wide spectrum of colors including pink, yellow, red, brown, purple and black, representing 1% to 8% of melanocytic tumors in children. Histologically, Spitz nevus has been subdivided into junctional, compound and intradermal type according to the location of neoplastic melanocytes in the skin. Rarely multiple benign juvenile melanoma arranged in clusters (agminated) or widespread (disseminated) are described. Less than 50 cases have been reported in the world literature. The grouped form usually occurs on the face of children on normal, but also hyperpigmented or hypopigmented skin, while the disseminated one in adults. A case of multiple agminated Spitz nevus arised on the face of a 2 years old girl is reported. The clinical presentations with a 3 years follow-up and the histologic features of this nevus are described as well as the therapeutic approach.

Child, Preschool↗