The Dimorphos ejecta plume properties revealed by LICIACube.

The Double Asteroid Redirection Test (DART) had an impact with Dimorphos (a satellite of the asteroid Didymos) on 26 September 20221. Ground-based observations showed that the Didymos system brightened by a factor of 8.3 after the impact because of ejecta, returning to the pre-impact brightness 23.7 days afterwards2. Hubble Space Telescope observations made from 15 minutes after impact to 18.5 days after, with a spatial resolution of 2.1 kilometres per pixel, showed a complex evolution of the ejecta3, consistent with other asteroid impact events. The momentum enhancement factor, determined using the measured binary period change4, ranges between 2.2 and 4.9, depending on the assumptions about the mass and density of Dimorphos5. Here we report observations from the LUKE and LEIA instruments on the LICIACube cube satellite, which was deployed 15 days in advance of the impact of DART. Data were taken from 71 seconds before the impact until 320 seconds afterwards. The ejecta plume was a cone with an aperture angle of 140 ± 4 degrees. The inner region of the plume was blue, becoming redder with increasing distance from Dimorphos. The ejecta plume exhibited a complex and inhomogeneous structure, characterized by filaments, dust grains and single or clustered boulders. The ejecta velocities ranged from a few tens of metres per second to about 500 metres per second.

Morphological and functional aspects of sciatic nerve regeneration after crush injury.

Experimental models for the investigation of nerve regeneration are critical in studying new strategies able to promote the repair process. The aim of the present work was to characterize morphological and functional aspects of sciatic nerve regeneration after mechanical crush injury in rodents. Morphological changes were assessed after a four minutes sciatic nerve injury induced by means of a standardized compression clip. Rat nerve samples were collected before injury and after 24 hours, four days, two weeks, and four weeks after injury, respectively. In an additional group with unilateral sciatic nerve injury, animals were evaluated for four weeks using walking track analysis and the sciatic static index (SSI) measured in both rearing and normal standing position. Histological study showed important axonal degeneration at four days and axonal regeneration at four weeks after injury. We observed no significant differences between SSI in rearing and normal standing stance and a strong correlation between SSI values measured in the two positions during the evaluation period. Positive correlations were also found for the footprint parameters. Our data provide a baseline characterization of the sciatic nerve crush injury that will further allow the investigation of peripheral nerve regeneration in the presence of potential neuroprotective agents in post-traumatic nerve repair.

Immunohistochemical profile of the estrogen and progesterone receptors in mammary benign lesions.

UNLABELLED: The immunohistochemical diagnosis for estrogen and progesterone receptors must be carried out in the tracking of every primary tumor, benign or malign, especially in the case of in situ carcinoma. MATERIAL AND METHOD: We have studied the expression of estrogen and progesterone receptors in benign lesions, identifying phenotypes depending on the presence of estrogen and progesterone receptors. RESULTS: The result "positive" or "negative" in the report sent to the doctor is not sufficient, the inclusion of the total score in the case of a positive result, the clone used, the usage / non-usage of antigenic exposure and also the quality control being necessary. The benign mammary lesions occur in the context of a hormonal imbalance, which, in the long run runs the risk of developing a mammary carcinoma. CONCLUSION: The further study of the hormonal spectrum of those lesions, considered as pre-malignant, may lead to the identification of some groups of hyperplastic lesions, presenting a high risk for developing a mammary cancer.

Human epidermal growth factor receptor 2 (HER2/neu) supraexpression in the mammary tumors.

A series of morphological and molecular factors can be used in order to appreciate the prognostic of mammary cancer. A multitude of molecular factors has been investigated in order to identify a prognostic factor, one of the most studied factors being HER2 (human epidermal receptor growth factor). For this purpose, we have carried out an immunohistochemical research, in order to determine the correlation between the presence of morphological factors in tumor formation, different stages of evolution, and the response to therapy. We have correlated HER2 expression with the histological type of carcinomas, the histological differential degree, ER, PR immunohistochemical expression, as well as the available clinical data. Within the studied carcinomas, we have identified a number of 98/156 (62.8%) carcinomas HER2/neu negative, out of which 74/156 (47.4%) did not reveal the presence of HER2/neu and 24/156 (15.4%) have been quantified as being 1+. The HER2/neu supraexpression was encountered in 58/156 (37.17%) cases: in 34/156 (21.8%) cases the immunostaining was interpreted as being 2+ and in 24/156 (15.4%) cases it was interpreted as being 3+. HER2/neu supraexpression should be routinely determined through immunohistochemical methods in all primary mammary tumors, especially in those poorly differentiated.