On the nucleolar and cytoplasmic RNA density during "cell dedifferentiation" represented by blastic transformation of human mature T lymphocytes - a cytochemical study.

The present study was undertaken to provide information on the nucleolar and cytoplasmic density in specimens stained for RNA during "cell dedifferentiation" represented by blastic transformation of mature T lymphocytes. Nucleolar and cytoplasmic RNA's were visualized using a simple cytochemical method followed by computer assisted densitometry and size measurements of digitised images. An increased nucleolar and cytoplasmic RNA density accompanying the blastic transformation was significant after 48 hours of cultivation with phytohemaglutinin (PHA) when stimulated cells were characterized the largest nucleolar size reflecting S or G2 phase of the cell cycle. On the other hand, significantly larger ratio of the nucleolar to cytoplasmic density was noted only after a shorter cultivation when stimulated cells were presumably in the G1 phase. Thus the increased nucleolar and cytoplasmic RNA density together represented an accompanying phenomenon of the cell proliferation and cycling state. From the methodical point of view, the nucleolar and cytoplasmic RNA densitometry appeared as a simple as well as useful additional method to study "dedifferentiation" or various cell states at the single cell level. In addition, it was also interesting that the increase of the nucleolar diameter in stimulated cells was much larger than that of the nucleolar density. Such difference suggested that the RNA content in nucleoli was related mainly to their size

Transvenozni pristup za indirektnu karotidno kavernoznu fistulu koristeći odvojive zavojnice: prikaz slučaja i pregled metoda liječenja

Carotid-cavernous fistula (CCF) is a relatively rare pathology with a low incidence compared with other vascular pathologies. They can be classified based on hemodynamics as low- or high-flow fistulas, and anatomically as direct or indirect fistulas. Anatomy of the shunt somewhat dictates the selection of endovascular treatment, meaning the venous or arterial approach and selection of embolizing materials. Although there is general agreement as to when to access CCF transvenously or transarterialy, which depends on the shunt being direct or indirect, there is no uniform agreement on which occlusion method should be used. Herein, we report a case of an 80-year-old woman treated for indirect CCF using detachable coils. We also provide a brief review of the literature, including recent advances in treatment of said entities. In conclusion, selection of both the approach and material used depends on the operator’s experience and preference.Karotidno kavernozna fistula je relativno rijetka patologija s niskom incidnecijom u odnosu na ostale vaskularne abnormalnosti. Hemodinamski se dijele na niskoporotočne i visokoprotočne, a anatomski na direktne i indirektne. Anatomija fistule određuje vrstu endovaskularnog tretmana, dakle arterijki ili venski pristup, kaoo I vrstu materijala kojom se vrši embolizacija. Iako postoji opći konsenzus oko primjene arterijskog ili venskog pristupa, ovisno o tome je li fistula direktna ili indirektna, ne postoji uniformni dogovor koja bi se metoda trebala koristiti u pojedinačnim slučajevima. Ovim radom smo prikazali slučaj osamdesetogodišnje bolesnice koja je liječena radi indirektne karotidno kavernozne fistule koristeći zavojnice. Također, prikazan je pregled literature i recentnog napretka u liječenju spomenutih entiteta. Zaključno, kako izbor pristup tako i izbor materijala ovise o iskustvu te preference operatera

On the nucleolar and cytoplasmic RNA density during "cell dedifferentiation" represented by blastic transformation of human mature T lymphocytes - a cytochemical study.

The present study was undertaken to provide information on the nucleolar and cytoplasmic density in specimens stained for RNA during "cell dedifferentiation" represented by blastic transformation of mature T lymphocytes. Nucleolar and cytoplasmic RNA's were visualized using a simple cytochemical method followed by computer assisted densitometry and size measurements of digitised images. An increased nucleolar and cytoplasmic RNA density accompanying the blastic transformation was significant after 48 hours of cultivation with phytohemaglutinin (PHA) when stimulated cells were characterized the largest nucleolar size reflecting S or G2 phase of the cell cycle. On the other hand, significantly larger ratio of the nucleolar to cytoplasmic density was noted only after a shorter cultivation when stimulated cells were presumably in the G1 phase. Thus the increased nucleolar and cytoplasmic RNA density together represented an accompanying phenomenon of the cell proliferation and cycling state. From the methodical point of view, the nucleolar and cytoplasmic RNA densitometry appeared as a simple as well as useful additional method to study "dedifferentiation" or various cell states at the single cell level. In addition, it was also interesting that the increase of the nucleolar diameter in stimulated cells was much larger than that of the nucleolar density. Such difference suggested that the RNA content in nucleoli was related mainly to their size

Aneuploidy and Confined Chromosomal Mosaicism in the Developing Human Brain

BACKGROUND: Understanding the mechanisms underlying generation of neuronal variability and complexity remains the central challenge for neuroscience. Structural variation in the neuronal genome is likely to be one important mechanism for neuronal diversity and brain diseases. Large-scale genomic variations due to loss or gain of whole chromosomes (aneuploidy) have been described in cells of the normal and diseased human brain, which are generated from neural stem cells during intrauterine period of life. However, the incidence of aneuploidy in the developing human brain and its impact on the brain development and function are obscure. METHODOLOGY/PRINCIPAL FINDINGS: To address genomic variation during development we surveyed aneuploidy/polyploidy in the human fetal tissues by advanced molecular-cytogenetic techniques at the single-cell level. Here we show that the human developing brain has mosaic nature, being composed of euploid and aneuploid neural cells. Studying over 600,000 neural cells, we have determined the average aneuploidy frequency as 1.25-1.45% per chromosome, with the overall percentage of aneuploidy tending to approach 30-35%. Furthermore, we found that mosaic aneuploidy can be exclusively confined to the brain. CONCLUSIONS/SIGNIFICANCE: Our data indicates aneuploidization to be an additional pathological mechanism for neuronal genome diversification. These findings highlight the involvement of aneuploidy in the human brain development and suggest an unexpected link between developmental chromosomal instability, intercellural/intertissular genome diversity and human brain diseases