Circulating miR-26b-5p and miR-451a as diagnostic biomarkers in medullary thyroid carcinoma patients.

PURPOSE/METHODS: The determination of tumour biomarkers is paramount to advancing personalized medicine, more so in rare tumours like medullary thyroid carcinoma (MTC), whose diagnosis is still challenging. The aim of this study was to identify non-invasive circulating biomarkers in MTC. To achieve this goal, paired MTC tissue and plasma extracellular vesicle samples were collected from multiple centres and microRNA (miRNA) expression levels were evaluated. RESULTS: The samples from a discovery cohort of 23 MTC patients were analysed using miRNA arrays. Lasso logistic regression analysis resulted in the identification of a set of circulating miRNAs as diagnostic biomarkers. Among them, miR-26b-5p and miR-451a, were highly expressed and their expression decreased during follow-up in disease-free patients in the discovery cohort. Circulating miR-26b-5p and miR-451a were validated using droplet digital PCR in a second independent cohort of 12 MTC patients. CONCLUSION: This study allowed the identification and validation of a signature of two circulating miRNAs, miR-26b-5p and miR-451a, in two independent cohorts reporting a significant diagnostic performance for MTC. The results of this study offer advancements in molecular diagnosis of MTC proposing a novel non-invasive tool to use in precision medicine.

The FXR agonist obeticholic acid inhibits the cancerogenic potential of human cholangiocarcinoma.

Cholangiocarcinoma (CCA) is an aggressive cancer with high resistance to chemotherapeutics. CCA is enriched in cancer stem cells, which correlate with aggressiveness and prognosis. FXR, a member of the metabolic nuclear receptor family, is markedly down-regulated in human CCA. Our aim was to evaluate, in primary cultures of human intrahepatic CCA (iCCA), the effects of the FXR agonist obeticholic acid (OCA), a semisynthetic bile acid derivative, on their cancerogenic potential. Primary human iCCA cell cultures were prepared from surgical specimens of mucinous or mixed iCCA subtypes. Increasing concentrations (0-2.5 µM) of OCA were added to culture media and, after 3-10 days, effects on proliferation (MTS assay, cell population doubling time), apoptosis (annexin V-FITC/propidium iodide), cell migration and invasion (wound healing response and Matrigel invasion assay), and cancerogenic potential (spheroid formation, clonogenic assay, colony formation capacity) were evaluated. Results: FXR gene expression was downregulated (RT-qPCR) in iCCA cells vs normal human biliary tree stem cells (p < 0.05) and in mucinous iCCA vs mixed iCCA cells (p < 0.05) but was upregulated by addition of OCA. OCA significantly (p < 0.05) inhibited proliferation of both mucinous and mixed iCCA cells, starting at a concentration as low as 0.05 µM. Also, CDCA (but not UDCA) inhibited cell proliferation, although to a much lower extent than OCA, consistent with its different affinity for FXR. OCA significantly induced apoptosis of both iCCA subtypes and decreased their in vitro cancerogenic potential, as evaluated by impairment of colony and spheroid formation capacity and delayed wound healing and Matrigel invasion. In general, these effects were more evident in mixed than mucinous iCCA cells. When tested together with Gemcitabine and Cisplatin, OCA potentiated the anti-proliferative and pro-apoptotic effects of these chemotherapeutics, but mainly in mixed iCCA cells. OCA abolished the capacity of both mucinous and mixed iCCA cells to form colonies when administered together with Gemcitabine and Cisplatin. In subcutaneous xenografts of mixed iCCA cells, OCA alone or combined with Gemcitabine or Cisplatin markedly reduced the tumor size after 5 weeks of treatment by inducing necrosis of tumor mass and inhibiting cell proliferation. In conclusion, FXR is down-regulated in iCCA cells, and its activation by OCA results in anti-cancerogenic effects against mucinous and mixed iCCA cells, both in vitro and in vivo. The effects of OCA predominated in mixed iCCA cells, consistent with the lower aggressiveness and the higher FXR expression in this CCA subtype. These results, showing the FXR-mediated capacity of OCA to inhibit cholangiocarcinogenesis, represent the basis for testing OCA in clinical trials of CCA patients.

Design and development of a sensorized cylindrical object for grasping assessment.

Aim of this work is to design and develop an instrumented cylindrical object equipped with force sensors, which is able to assess grasping performance of both human and robotic hands. The object is made of two concentric shells between which sixteen piezoresistive sensors have been located in order to measure the forces applied by the hand fingers during grasping. Furthermore, a magneto-inertial unit has been positioned inside the object for acquiring information about object orientation during manipulation. A wireless communication between the electronic boards, responsible for acquiring the data from the sensors, and a remote laptop has been guaranteed. The object has been conceived in such a way to be adopted for evaluating both power and precision grasps and for measuring the forces applied by each finger of the hand. In order to evaluate object performance, a finite element analysis for estimating the deformation of the external shell for different force values has been carried out. Moreover, to evaluate object sensitivity, a static analysis of the force transmitted by the external shell to the underlying sensors has been performed by varying the thickness of the shells. The obtained preliminary results have validated the feasibility of using the developed object for assessing grasping performed by human and robotic hands.

A bio-inspired force control for cyclic manipulation of prosthetic hands.

The human hand is considered as the highest example of dexterous system capable of interacting with different objects and adapting its manipulation abilities to them. The control of poliarticulated prosthetic hands represents one important research challenge, typically aiming at replicating the manipulation capabilities of the natural hand. For this reason, this paper wants to propose a bio-inspired learning architecture based on parallel force/position control for prosthetic hands, capable of learning cyclic manipulation capabilities. To this purpose, it is focused on the control of a commercial biomechatronic hand (the IH2 hand) including the main features of recent poliarticulated prosthetic hands. The training phase of the hand was carried out in simulation, the parallel force/position control was tested in simulation whereas preliminary tests were performed on the real IH2 hand. The results obtained in simulation and on the real hand provide an important evidence of the applicability of the bio-inspired neural control to real biomechatronic hand with the typical features of a hand prosthesis.

Development and preliminary testing of an instrumented object for force analysis during grasping.

This paper presents the design and realization of an instrumented object for force analysis during grasping. The object, with spherical shape, has been constructed with three contact areas in order to allow performing a tripod grasp. Force Sensing Resistor (FSR) sensors have been employed for normal force measurements, while an accelerometer has been used for slip detection. An electronic board for data acquisition has been embedded into the object, so that only the cables for power supply exit from it. Validation tests have been carried out for: (i) comparing the force measurements with a ground truth; (ii) assessing the capability of the accelerometer to detect slippage for different roughness values; (iii) evaluating object performance in grasp trials performed by a human subject.

A preliminary health technology assessment of a guidance system for interventional radiology.

Disruptive innovation in biomedical devices have to be carefully assessed in order to be included in the clinical practice, especially when these new systems interact with the human body. In this scenario the guidance devices for interventional radiology represent an area of great interest. In this paper a CT-navigation system, SIRIO, used for percutaneous interventions such as biopsy, thermal ablation, percutaneous interventional, is tested and assessed. The technical features of the system in terms of efficacy and safety and the comparison with the traditional CT-guided biopsy are analyzed. According to the clinical evidences, biopsies carried out with SIRIO show an important reduction of number of CT scans, procedure's time and radiation dose absorbed by the patients. The analysis of the technology costs, the social impact related to the benefits to clinicians and patients are also reported. Although SIRIO does not have an appropriate reimbursement procedure, short- and long-term benefits introduced by this device are discussed.

Preliminary study of early histomorphometric changes in hepatic steatosis.

The first endpoint of this study was to find new markers that document the progression of hepatic steatosis through quantitative histomorphometric analysis in the absence of hemodynamic changes. The second endpoint was to start building a mathematical database to help to achieve a score in the future. For this study we enrolled 130 random patients, including 10 with normal histology despite suspected disease, 70 positive for steatosis, 20 affected by nonalcoholic steato hepatitis, and 30 with hepatitis virus C or B-related cirrhosis. One hundred thirty images were analyzed for a total of 1,320 sinusoids. Each image was processed with a custom program written with the use of the Vision toolbox of the Labview platform, following a semiautomated procedure. The mean sinusoidal areas (SAs) and percentage fractions of parenchymal area occupied by sinusoids (SA/PA) were subdivided into 3 groups. Finally, we analyzed the form of sinusoids, approximating them to an ellipse, to be able to define the relationship between the 2 axes with the aim of proposing a parameter, "local hydraulic resistance" (LHR), that was proportional to the resistance to blood flow within the bounds of the histologic specimen. Among the images, we observed a difference in the size of SAs among the 3 groups of patients, namely, normal, steatotic of different stages, and cirrhotic patients. In fact, there was evidence of a reducted SA when steatosis was <30%, with an average value of 0.0032 mm(2), patients with steatosis of 30%-50% showed an average SA of 0.0024 mm(2), and there was a further reduction among subjects with steatosis grades >50% (mean 0.0017 mm(2)). The LHR value showed that the morphometric parameter SA/PA could be quantitatively interpreted also as a functional impairment relative to the increased resistance opposing blood flow in pathologic conditions.

Polycystic liver diseases.

Polycystic liver diseases (PCLDs) are genetic disorders with heterogeneous etiologies and a range of phenotypic presentations. PCLD exhibits both autosomal or recessive dominant pattern of inheritance and is characterized by the progressive development of multiple cysts, isolated or associated with polycystic kidney disease, that appear more extensive in women. Cholangiocytes have primary cilia, functionally important organelles (act as mechanosensors) that are involved in both normal developmental and pathological processes. The absence of polycystin-1, 2, and fibrocystin/polyductin, normally localized to primary cilia, represent a potential mechanism leading to cyst formation, associated with increased cell proliferation and apoptosis, enhanced fluid secretion, abnormal cell-matrix interactions, and alterations in cell polarity. Proliferative and secretive activities of cystic epithelium can be regulated by estrogens either directly or by synergizing growth factors including nerve growth factor, IGF1, FSH and VEGF. The abnormalities of primary cilia and the sensitivity to proliferative effects of estrogens and different growth factors in PCLD cystic epithelium provide the morpho-functional basis for future treatment targets, based on the possible modulation of the formation and progression of hepatic cysts.

New insights into liver stem cells.

Hepatic progenitor cells are bi-potential stem cells residing in human and animal livers that are able to differentiate towards the hepatocytic and the cholangiocytic lineages. In adult livers, hepatic progenitor cells are quiescent stem cells with a low proliferating rate, representing a reserve compartment that is activated only when the mature epithelial cells of the liver are continuously damaged or inhibited in their replication, or in cases of severe cell loss. Hepatic progenitor cell activation has been described in various acute and chronic liver diseases. Their niche is composed by numerous cells such as Hepatic Stellate Cells, endothelial cells, hepatocytes, cholangiocytes, Kupffer cells, pit cells and inflammatory cells. All these cells, numerous hormones and growth factors could interact and cross-talk with progenitor cells influencing their proliferative and differentiative processes. Hepatic progenitor cells and their niche could represent, in the near future, a target for therapeutic approaches to liver disease based on cell-specific drug delivery systems. Isolation and transplantation of hepatic progenitor cells could represent a new approach for therapy of end-stage chronic liver diseases, as they offer many advantages to transplantation of mature hepatocytes. The possibility of applying stem cell therapy to liver diseases will represent a major goal in this field.

An overview on immune system and migraine.

The pathogenesis of migraine is still unclear, but much evidence led us hypothesize that it can be associated with immune system modification, so that a role for cytokines has been suggested. Cytokines are important mediators of the immune and inflammatory pathways and their receptors are widely express in central nervous system (CNS) by all cell types, including neurons, indicating that they can act on neuronal receptors. Cytokines are now considered to be the pain mediators in neurovascular inflammation. Furthermore cytokines may be a cause of the migraine pain: in fact an high levels of chemokines could stimulate the activation of trigeminal nerves, the release of vasoactive peptides or other biochemical mediators, such as nitric oxide, and then to cause inflammation. In this scenario, many studies on humans have focused the attention on peripheral and central levels of cytokines, but data obtained are highly controversial. Since at the moment there is not a conclusive evidence of the role played by cytokines in migraine, the authors present and comment the latest reports regarding cytokine modification and the role of the immune system in migraine.

[Morphological aspects of atherosclerosis lesion: past and present]. / Aspetti morfologici della lesione ateromasica tra passato e presente.

Atherosclerosis is an inflammatory process disease that involves the artery wall and that is characterized by the progressive accumulation of lipids. The term arteriosclerosis has been created by Lobstein in 1833. Subsequently, during the 19th century, the contribution of Rokitansky and Virchow was important to elucidate the pathogenesis of arteriosclerosis and the morphologic aspects of the plaque. In the beginning of the 20th century, Aschoff was a leading proponent who regarded the morphologically different intimal lipid deposits of children and adults as early and late stages of one disease and he called them atherosis and atherosclerosis, respectively. The first classification of atherosclerosis was made by the World Health Organization (WHO) in 1958 and it consisted of the following sequence: fatty streak, atheroma, fibrous plaque and complicated lesions. In 1990s, thanks to much more sensitive techniques, the American Heart Association (AHA) proposed a new morphological classification based on eight lesion types designated by Roman numerals which indicate the usual sequence of lesion progression. Finally, Virmani et al. (2000) described a classification with the add of a specific plaque type, not recognized by the AHA classification, called "thin fibrous cap atheroma" which is more likely to rupture. The atherosclerotic process is characterized by typical ultrastructural changes that mainly involve the endothelial and smooth muscle cells. The morphological alterations of the endothelium are associated with dysfunctions leading to a proinflammatory and prothrombotic phenotype. This process seems to be due to turbulent blood flow and low fluid shear stress that normally occurs in particular regions of the vascular tree. Inflammation has a key role in the pathogenesis of atherosclerosis and it is supported by numerous factors such as modified LDL, hypertension, diabetes mellitus, free radicals and, in particular, by infectious agents such as Chlamydia pneumoniae.

Angiosarcoma of the heart: structural and ultrastructural study.

BACKGROUND: Primary cardiac tumours are rare. Nearly 70% of primary cardiac tumours are benign, the majority of which are represented by myxomas. The most frequent primary cardiac neoplasm is the angiosarcoma that represents 31% of primary cardiac malignant. We report a particular clinical case of cardiac angiosarcoma, its light and transmission electron microscopic aspects and a review of the recent literature. METHODS: A 52 years old man died for a severe right ventricle filling deficit caused by an intracavitary tumour originated from the right atrial anterolateral wall. The fragments obtained from autoptic tumoral cardiac tissue were processed for light and electron microscopy. The section were stained with haematoxilineosin, Masson trichromic and Gomori method. An immunohistochemical study for vimentin, Factor VIII related antigen and peroxidase-conjugated lectin from Ulex Europaeus was also performed using the unlabed peroxidase-antiperoxidase method. RESULTS: The hematoxylin-eosin staining showed that the tumoral mass was composed by a well-differentiated histotype characterized by numerous vascular areas in which neoplastic cells were loosely and irregularly arranged to form incomplete vessels or anastomized blood-filled vascular channels. On the other hand, some less-differentiated solid areas were present and irregularly surrounded the differentiated vascular areas. Results of Ulex Europeaeus Agglutinin I labelling were positive in both solid and vascular areas of the tumour although the positive reaction was less evident in the solid zones Factor VIII related antigen positive cells were less numerous and mainly found in vascular areas. The observation by electron microscopy showed the lack of evident pinocytotic vesicles, the presence of thin and delicate cytoplasmatic processes, Weibel-Palade bodies, and also the disarrangement of the extracellular fibrous matrix. CONCLUSION: The light microscopy observation and immunohistochemical study underscore that is not easy to obtain information about the level of differentiation of this tumour. The presence of blood-filled lumina and the identification of typical markers of endothelial cells seems to indicate a well-differentiated nature. However, the ultrastructural findings seem to indicate a less differentiated nature.

Alpha-SMA expression in hepatic stellate cells and quantitative analysis of hepatic fibrosis in cirrhosis and in recurrent chronic hepatitis after liver transplantation.

BACKGROUND: The alpha isotype of actin expressed by hepatic stellate cells reflects their activation to myofibroblast-like cell and has been directly related to experimental liver fibrogenesis, and indirectly to human fibrosis in chronic liver disease. AIMS: To evaluate the changes in distribution and percentage of alpha-smooth muscle actin-positive hepatic stellate cells and the correlation with the degree of the fibrosis in cirrhotic livers, as well as in patients with recurrent HCV chronic hepatitis after liver transplantation. METHODS: Human liver biopsies were divided in four groups: (1) normal livers obtained from cadaveric liver donors (n=35), (2) cirrhosis post-HBV hepatitis (n=11), (3) cirrhosis post-HCV hepatitis (n=10), and (4) post-transplant recurrent HCV chronic hepatitis (n=13). Samples were stained with anti-alpha-smooth muscle actin antibody by immunoperoxidase method and semi-quantitatively evaluated. Liver fibrosis was assessed from specimens stained with Masson's trichrome and quantified by computer image analysis. RESULTS: The percentage of alpha-smooth muscle actin-positive hepatic stellate cells was significantly higher in the HBV cirrhosis, HCV cirrhosis and post-transplant HCV recurrent hepatitis groups (36.1+/-15.2, 23.8+/-19.7 and 27.8+/-16.4%, respectively) compared to the liver donor group (2.9+/-4.0%). The alpha-smooth muscle actin-positive hepatic stellate cells to fibrous tissue ratio were significantly higher in the post-transplant recurrent HCV hepatitis group (2.36+/-1.12) compared to both the donor livers and the HCV cirrhosis groups (0.74+/-1.09 and 1.03+/-0.91, respectively). The alpha-smooth muscle actin-positive hepatic stellate cell percentage and fibrosis correlated positively in the post-transplant recurrent HCV hepatitis group and negatively in the HCV cirrhosis group. No difference in the immunohistochemical and morphometrical variables was found between the HCV cirrhosis and HBV cirrhosis groups. CONCLUSIONS: These results indirectly confirm that, in vivo, alpha-smooth muscle actin expression is a reliable marker of hepatic stellate cells activation which precedes fibrous tissue deposition even in the setting of recurrent HCV chronic hepatitis after liver transplantation, and it could be useful to identify the earliest stages of hepatic fibrosis and monitoring the efficacy of the therapy. In the presence of advanced cirrhosis other factors, rather than alpha-smooth muscle actin-positive hepatic stellate cells, may sustain fibrosis deposition.

Lateral costal artery: accessory thoracic vessel of clinical interest.

The lateral costal artery (LCA), a supernumerary branch of the internal thoracic artery (ITA), occurs in several ethnic groups on one side of the thorax or on both, in 15-30% of cases. It has been considered responsible for the "steal-syndrome" of the coronary blood after coronary artery bypass grafting and it used occasionally for myocardial revascularization. To clarify its functional significance, an interpretation based on our findings and human and comparative anatomy and embryology has been attempted. We report on a case where a right LCA of about 2 mm in caliber, rising from the ITA 2.5 cm below the subclavian, coursed as far as the 4th intercostal space for a distance of 13 cm after the anterior axillary line. Anastomosing with the intercostal arteries, it can act as a blood derivative circuit of the thoracic wall. Embryologically, this artery, like the normal parietal arteries of the trunk, might form a longitudinal channel connecting the intersegmental arteries. In mammals having a thoracic cage transversely restricted (quadrupeds), the ITA is more lateral than in primates having a circular thorax, and gives off a ventral branch toward the sternum. It might be hypothesized that the sternal branch occurring in quadrupeds, undergoing adaptation to the thoracic shape of primates, may become the main trunk of the ITA, whereas the LCA may be the remnant of the ITA of quadrupeds. Because the LCA ran partly along the "milk line" of humans, it might be regarded as a supernumerary mammary artery.