Fingermark age determinations: Legal considerations, review of the literature and practical propositions.

The question of the age of fingermarks is often raised in investigations and trials when suspects admit that they have left their fingermarks at a crime scene but allege that the contact occurred at a different time than the crime and for legal reasons. In the first part of this review article, examples from American appellate court cases will be used to demonstrate that there is a lack of consensus among American courts regarding the admissibility and weight of testimony from expert witnesses who provide opinions about the age of fingermarks. Of course, these issues are not only encountered in America but have also been reported elsewhere, for example in Europe. The disparity in the way fingermark dating cases were managed in these examples is probably due to the fact that no methodology has been validated and accepted by the forensic science community so far. The second part of this review article summarizes the studies reported on fingermark dating in the literature and highlights the fact that most proposed methodologies still suffer from limitations preventing their use in practice. Nevertheless, several approaches based on the evolution of aging parameters detected in fingermark residue over time appear to show promise for the fingermark dating field. Based on these approaches, the definition of a formal methodological framework for fingermark dating cases is proposed in order to produce relevant temporal information. This framework identifies which type of information could and should be obtained about fingermark aging and what developments are still required to scientifically address dating issues

The role of Collagen type VI in fibrosis

In this review, collagen type VI structure and function are described and its role in fibrosis. Collagen type VI is an extracellular matrix (ECM) component. This protein forms a microfibrillar network in most connective tissues, where it is mostly found. Type VI collagen is produced mainly by fibroblasts, but also by macrophages. The structure of collagen type VI is complex. Collagen VI consist of three α chains, and recently three novel α chains are added. The assembly of this collagen type is a complex process. The three chains, α1, α2 and α3, form a triple helical monomer followed by assembly into disulfide bonded antiparallel dimers. These dimers align to form tetramers that are also stabilized by the disulfide bonds. In the last step, the tetramers are secreted into the ECM forming long molecular chains, known as microfibrils. The function of type VI collagen is not been identified clearly. Studies have shown that collagen VI interacts with several extracellular matrix proteins. Also is indicated that collagen VI anchors large interstitial structures and it has a critical role in integrity of tissues. Collagen VI is expressed in many tissues especially is the muscles. Mutations of the collagen VI genes cause two myopathies, Bethlem myopathy and Ullrich congenital muscular dystrophy. Collagen type VI has an important role in the remodeling of extra cellular matrix and also in several tissues fibrosis. At present, it is known that collagen VI has a role in liver, lung, cardiac and renal fibrosis. It is showed that collagen type VI can be used as a biomarker for liver fibrosis, a non-invasive method. Future studies are required for determination of the role of collagen VI in fibrosis of other tissues and for understanding the mechanism behind this.