[Ultrastructural aspects in the development of the human nephron--electron microscopy study]. / Aspecte ultrastructurale în dezvoltarea nefronului uman. Studiu de microscopie electronica.

UNLABELLED: We have looked for electron microscopy aspects tissue fragments of human nephrons harvested from fetuses of 7,5-19 weeks to show ultrastructure aspects of the nephron during development. MATERIAL AND METHODS: We have used 9 fragments from human embryos; Four cases were aged of 7,5, 8, 12 and 17 weeks. The other 5 cases were between 18 and 19 weeks. Tissue fragments were fixed in glutaraldehyde at 4 degrees C and processed by the classic technique. RESULTS: The electron microscopy study shows the evolutive steps of the human nephron (stages I-IV), stages met for the 12-19 weeks embryo. For the cases under this age the meta-nephrogenic blastema was dominant. In the IVth development stage, the cells in the proximal tubule show a higher development degree than the distal segments. CONCLUSION: These observations indicate that during early development the proximal segment is better developed and probably more functional than the distal segments.

[Gelatinases in peri-implantation stage]. / Gelatinazele în perioada periimplantara.

The periimplantation stage in mice is marked around the 5th day after mating by blastocyst presence in the emdometrium. The events that are marking the implantation event are focused on the evolution of the extracellular matrix around the mezenchime cells that undergoes decidualization. The inductive process is guided by gelatinases and the purpose of our study is to demonstrate their presence at this level.

[Periodontitis, a risk factor for cardiovascular diseases?]. / Periodontitele, factor de risc pentru bolile cardiovasculare?

Exist a statistically significant association between a diagnosis of coronary heart disease and certain oral health parameters. These parameters are independent and more strongly associated with coronary heart disease than were recognized risk factors, such as serum cholesterol levels, body mass index, diabetes and smoking status. The correlation between serum and salivary cholesterol concentration and the role of salivary lipids in oral health have been poorly characterized. Lipids in saliva are mostly glandular in origin, through some may diffuse diffuse directly from the serum. The surface of the enamel (in case of dietary fat which have an cariostatic effect) is protected against demineralization by a mixture of salivary lipids and proteins. Salivary lipids may have anucleating role in the early mineralization of the dental plaque. The prevalence of periodontal disease may be increased in patients with atherosclerosis, and dental and periodontal infections have been shown to be associated with occurrence of acute and chronic coronary heart disease. Among the known risk factors of atherosclerosis, high serum lipid levels, especially cholesterol may be important with regard to periodontal health.