Different eyes, different views. Scanning Electron Microscopy applied to forensic investigations

The Scanning Electron Microscope (SEM) is an extremely versatile instrument, essential in a wide array of applications in forensic analysis: for example, it is used to analyze gunshot residue, bullet fingerprints, bullet wipe or patterns around the bullet hole, to examine traces of foreign material embedded in or adhered to bullets (which can provides critical information in the trajectory reconstruction of spent bullets); to study environmental dusts, fibers (both natural and artificial) and to identify unknown small particles; to detect non visible blood stains; to analyze diatoms in drowning cases; and for ink and paper analysis. One central feature of SEM is its ability of providing both panoramic and highly magnified views of the same sample, giving an almost 3D view of the specimen. It is the ideal trait d’union between macroscopic information collected during autoptic or investigative activity and microscopic information obtained with the light microscope. Above all, SEM allows performing a progressive and targeted microdissection of the sample. In this presentation, a selected number of investigations are shown in order to illustrate through specific cases general purpose applications. An elderly man was killed with several blows of axe at the head. SEM investigation allowed us to reconstruct the sequence of the blows, to recognize the type of weapon, to determine how this latter was used and how sharp it was. These results allowed the police to reject the initial version of the suspected, which was eventually convicted of willful murder. A young man died with multiple traumatic and fulguration lesions. SEM analysis allowed us to perform a detailed study of the burnt tissue and to reconstruct the path of the electric discharge, concluding that the primary causa mortis was an accidental electrocution, which caused the subsequent trauma. A child died of a sudden, dramatic internal bleeding. The autopsy revealed that some time before she had swallowed a coin battery which had become lodged in the oesophagus. Here the decaying products of the battery caused an electro-chemical dissection of the oesophagus and, finally, of the descending aorta. The SEM analysis revealed the details of the progressive degeneration of the surrounding tissues

Distinguishing blood and lymph vessel invasion in breast cancer: a prospective immunohistochemical study

Recently, peritumoural (lympho)vascular invasion, assessed on haematoxylin–eosin (HE)-stained slides, was added to the St Gallen criteria for adjuvant treatment of patients with operable breast cancer (BC). New lymphatic endothelium-specific markers, such as D2-40, make it possible to distinguish between blood (BVI) and lymph vessel invasion (LVI). The aim of this prospective study was to quantify and compare BVI and LVI in a consecutive series of patients with BC. Three consecutive sections of all formalin-fixed paraffin-embedded tissue blocks of 95 BC resection specimens were (immuno)histochemically stained in a fixed order: HE, anti-CD34 (pan-endothelium) and anti-D2-40 (lymphatic endothelium) antibodies. All vessels with vascular invasion were marked and relocated on the corresponding slides. Vascular invasion was assigned LVI (CD34⊕ or ⊖/D2-40⊕) or BVI (CD34⊕/D2-40⊖) and intra- (contact with tumour cells or desmoplastic stroma) or peritumoural. The number of vessels with LVI and BVI as well as the number of tumour cells per embolus were counted. Results were correlated with clinico-pathological variables. Sixty-six (69.5%) and 36 (37.9%) patients had, respectively, LVI and BVI. The presence of ‘vascular' invasion was missed on HE in 20% (peritumourally) and 65% (intratumourally) of cases. Although LVI and BVI were associated intratumourally (P=0.02), only peritumoural LVI, and not BVI, was associated with the presence of lymph node (LN) metastases (pperi=0.002). In multivariate analysis, peritumoural LVI was the only independent determinant of LN metastases. Furthermore, the number of vessels with LVI was larger than the number of vessels with BVI (P=0.001) and lymphatic emboli were larger than blood vessel emboli (P=0.004). We demonstrate that it is possible to distinguish between BVI and LVI in BC specimens using specific lymphatic endothelium markers. This is important to study the contribution of both processes to BC metastasis. Furthermore, immunohistochemical detection of lymphovascular invasion might be of value in clinical practice

Lympho-vascular invasion in BRCA related breast cancer compared to sporadic controls

<p>Abstract</p> <p>Background</p> <p>Germline mutations in the BRCA1 gene predispose to the development of breast cancer, exhibiting a specific histological phenotype. Identification of possible hallmarks of these tumors is important for selecting patients for genetic screening and provides inside in carcinogenetic pathways.</p> <p>Since BRCA1-associated breast cancers have pushing borders that prevent them from easily reaching vessels and are often of the medullary (like) type that is known to have a low rate of lympho-vascular invasion (LVI), we hypothesized that absence of LVI could characterize BRCA1 related breast cancer.</p> <p>Methods</p> <p>A population of 68 BRCA1 related invasive breast cancers was evaluated for LVI by an experienced breast pathologist blinded to mutation status, and compared to a control group matched for age, grade and tumor type.</p> <p>Results</p> <p>LVI was present in 25.0% of BRCA1 related cases, compared to 20.6% of controls (P = 0.54, OR = 1.29, CI 0.58-2.78).</p> <p>Conclusion</p> <p>LVI is frequent in BRCA1 germline mutation related breast cancers, but seems to occur as often in sporadic controls matched for age, grade and tumor type. Apparently, these hereditary cancers find their way to the blood and lymph vessels despite their well demarcation and often medullary differentiation.</p

Ultrastructural findings of congenital dyserythropoietic sickle cell beta thal-associated anemia

The ultrastructural findings of erythroblasts and reticulocytes in one case of congenital dyserythropoiethic anemia (CDA) associated with a haemoglobinopathy, sickle cell beta thalassemia minor (Type V CDA), is described. The observations can be summarized as follows: 1) A lot of large breaks are present in the erythroblast nuclear envelope. 2) Nuclear membrane evaginations are filled with dense loose chromatin. 3) Electron-transparent areas (moth eaten chromatin) are evident in dense chromatin. 4) Electron-dense granular material, related to altered haemoglobin chain storage, is evident in the nucleus and in the cytoplasm. 5) Iron deposits are present in mitochondrial matrix. 6) Myelinic figures are present in reticulocyte cytoplasm. For the first time the ultrastructural findings in this type of associated CDA are described and related to the double origin of clinical symptoms

Morphology of epiphyseal apparatus of a ranid frog (Rana Esculenta)

Morphological, histochemical and ultrastructural investigations on epiphyseal apparatus of Rana Esculenta were made. The most important findings were the following: 1) metaphyseal cartilage is localized inside proximal diaphyseal compact bone as a plug; 2) metaphyseal cartilage do not reduce in thickness during ageing; 3) metaphyseal cartilage do not show vascular invasion and do not mineralize in degenerative zone; 4) trabecular bone was not at al1 evident in this animal; 5) externa1 periosteum is well vascularized and proliferates in correspondence to marginal epiphyseal end of the diaphyseal. From these results the hypothesis that the ranid frog bone growth is not due to metaphyseal metabolism (as in avian and mammals) but to bone periosteal marginal mineralization is reached

The effect of the levonorgestrel releasing intrauterine system on endometrial hyperplasia: An Australian study and systematic review

Background: The levonorgestrel intrauterine system (LNG-IUS) provides effective contraception and treatment for menorrhagia and is used to prevent endometrial hyperplasia (EH) in women taking unopposed oestrogens