1,721,044 research outputs found
The dual response of protein kinase Fyn to neural trauma: early induction in neurons and delayed induction in reactive astrocytes.
No full textIntroduzione a Biologia dello Sviluppo. Principi generali dello Sviluppo.
No full textCon il termine “sviluppo” ci riferiamo fondamentalmente all’insieme degli eventi attraverso cui da un uovo fecondato si genera un organismo pluricellulare, composto da differenti tipi cellulari, organizzati in tessuti ed organi, ciascuno deputato a svolgere una specifica funzione (di sostegno, di protezione, di nutrizione, di locomozione, sensoriale, riproduttiva, ecc.) e con una sua ben precisa forma tridimensionale e localizzazione spaziale rispetto alle altre strutture che compongono l’organismo
Mukaiyama reagent: An efficient reaction mediator for rapid synthesis of 1,2-disubstituted-1H-benzo[d]imidazoles
No full textWithin the field of medicinal chemistry, 1,2-disubstituted benzimidazoles represent a privileged class of nitrogen-based heterocycles but, unlike 2-substitued derivatives, few synthetic methods have been reported. In this context, we developed a rapid, metal-free, and straightforward method to prepare a series of 1,2-disubstituted-1H-benzo[d]imidazoles starting from 1,2-phenylendiamines and various aromatic and aliphatic aldehydes in the presence of the Mukaiyama reagent. The reaction proceeded at room temperature with good product yields within few minutes
Beneath the surface of eyebrows: investigating the vermiculate pattern in medieval central Italy.
No full textThe skull is affected by different porosities, being physiological, pathological, or alterations difficult to classify in terms of aetiology such as that related to the vermiculate pattern (VP). The VP is a distinct alteration morphologically characterized by grooves and pitting, and it has been described on the cortical surface of the brow region of fossil hominids, modern human populations from identified osteological collections , and non-human primates. Considering the poor knowledge of VP and its aetiology as well as the scarce existing research on this topic, the aim of this study is to analyze the VP for the first time in a historical archaeological population. A sample of 118 adults from the medieval rural site of Pieve di Pava (Tuscany, 10th -12th century CE) was chosen. Gross examination of superciliary arches, supraorbital margins, and zygomatic bones revealed VP was significantly present (X2=25.124, d.f.=1, p < 0.001) among the male subsample (94.0%, n=67) compared to the female subsample (54.9%, n=51); VP was present in both sexes across all age groups but it was more frequently observed among individuals aged 35+ (84.9%, n=73). No clear trend was found when testing its correlation with other cranial lesions like cribra orbitalia (r=0.13) or chronic maxillary and frontal sinusitis (r=0.07 and r=0.15, respectively).
Although further studies on imaging and histology of VP are needed to understand the underlying mechanism responsible for this alteration, this preliminary research represents one the first attempt to investigate this condition in the osteoarchaeological material
Common inflammatory reaction for uncommon place: a case of sphenoid sinusitis from Late Roman Etruria (Tuscany, second half of the 3rd-4th centuries AD)
No full textInflammatory bone reaction is one of the most common pathological alterations observed in ancient human skeletal remains. However, such finding is usually detected in connection to the external cranial surface and postcranial bones, while the inner structures of the sinuses are rarely encountered due to difficult access to their observation.
The aim of this study is to present an uncommon location of chronic sinusitis observed thanks to appropriate recovery of osteological remains during archaeological excavations and to careful laboratory procedures.
The macroscopical skeletal analysis of a mature male individual (US 289) from the site of ‘Volterra Le Colombaie’, in Tuscany (central Italy, second half of the 3rd-4th centuries AD), allowed us to appreciate deposits of grey porous woven bone adhering to the underlying cortex of numerous fragments of the left sphenoid sinus. This pathological alteration was diagnosed as a case of isolated chronic sphenoid sinusitis in active stage at the time of death of this individual. Different organisms are responsible for the inflammation of the sphenoid sinuses, with the Staphylococcus aureus being the most common pathogen, followed by the Aspergillus species among the fungal organisms.
Bone remodeling and bone sclerosis, as seen in the present case, are signs of important long-standing inflammation of the sinuses, usually associated with fungal infection in individuals with compromised immune systems (e.g., old people or those affected by serious pre-existing conditions). Sphenoid sinusitis is a rare entity in clinical practice and, to our knowledge, no cases have been detected so far in paleopathology
Insulin receptor in mouse neuroblastoma cell line N18TG2: binding properties and visualization with colloidal gold.
No full textInsulin function in the nervous system is still poorly understood. Possible roles as a neuromodulator and as a growth factor have been proposed (Baskin et al., 1987, Ann. Rev. Physiol. 49, 335-347). Stable cell lines may provide an appropriate experimental system for the analysis of insulin action on the various cellular components of the central nervous system. We report here a study to investigate the presence and the properties of insulin specific binding sites in the murine neuroblastoma line, N18TG2, together with insulin action on cell growth and metabolism. Also, receptor internalization has been studied. Binding experiments, carried out in standard conditions at 20 degrees C, enabled us to demonstrate that these cells bind insulin in a specific manner, thus confirming previous findings on other cell lines. Saturation curves showed the presence of two binding sites with Kd 0.3 and 9.7 nM. Competition experiments with porcine and bovine insulin showed an IC50 of 1 and 10 nM, respectively. Competition did not occur in the presence of the unrelated hormones ACTH and FSH. Dissociation experiments indicated the existence of an internalization process of the ligand-receptor complex; this was confirmed by an ultrastructural study using gold conjugated insulin. As far as the insulin action in N18TG2 cells is concerned, physiological concentrations stimulate cell proliferation, whereas no stimulation of glucose uptake was observed, indicating that insulin action in these cells is not mediated by general metabolic effects. On the basis of these data, N18TG2 line appears to be a very suitable model for further studies of the neuronal type insulin receptors, and possibly insulin specific action on the nervous system
(Dis)abled people in pre-Roman times: a case study from Pontecagnano (southern Italy, 4th century BCE)
No full textGoing Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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