Bleeding jejunal varices and portal thrombosis in a splenectomized patient with hereditary spherocytosis

Bleeding from varices located in the small bowel is a very uncommon finding; nonetheless, such events accompany with a high mortality rate (1– 4). Moreover, early diagnosis of jejunal or ileal varices cannot usually be accomplished with standard diagnostic tools (ie, esophagogastroduodenoscopy, colonoscopy). Most reports in the literature relate to subjects with liver cirrhosis, often with hepatocarcinoma; in unusual anatomical situations, varices may develop beyond the ligament of Treitz in adjunct to the far more common location in the esophageal and gastric wall. Thrombosis of the portal vein is a common feature in such conditions. Portal thrombosis has also been described in association with overt or latent myeloproliferative diseases (5); its occurrence in nonneoplastic hematological conditions in subjects with normal liver function is quite uncommon. This report describes the observation of jejunal varices, with repeated episodes of “melena of unknown origin,” some of which quite severe, as their clinical presentation in a patient with portal thrombosis and with otherwise absolutely normal liver function, who had undergone splenectomy for hereditary spherocytosis in early adolescence

Investigating the effects of odour integration in reading and learning experiences

Books are the tools used for reading novels and stories, but also for educational purposes. Conventional books have undergone a radical transformation in recent years due to the use of new technologies. However, even today the technological devices used for reading e-books are still poorly exploited, despite the fact that they represent a fundamental tool to make the reading experience more immersive by using a complete multisensory approach. In this perspective, one sense that represents an important element of human perception is the sense of smell. Consequently, authors make the hypothesis that the introduction of odours during reading sessions could increase the user experience and the learning performances. In order to demonstrate these hypotheses, the authors have defined and carried out several experimental testing sessions. The analysis of the collected data proved that the introduction of odour does not disturb the reader during reading activities but, on the contrary, can actually make the experience more immersive. Similarly, odours do not disturb studying activities, but they can instead increase the level of concentration and people's learning performance

Design of an Intrinsically Motivating AR Experience for Environmental Awareness

Augmented Reality seems a promising tool to provide engaging and effective educational experiences, thanks to its potentiality in stimulating intrinsic motivation, that could influence the learning process and the attitude of the users towards behaviours. This paper presents the Resized Plastic Augmented Reality learning experience, designed on the basis of Dunleavy's framework to provide a systemic overview of the microplastics issue to allow users to understand its mechanisms, educate them about their role in the system and help them to connect this information to their everyday actions

A novel educational model based on "knowing how to do" paradigm implemented in an academic makerspace

The design discipline is faced with radical changes related to new technologies and to an increasingly globalized world with more and more competitive markets. These factors are profoundly influencing methods and processes of design, and the knowledge and skills related to the designer's role. Consequently, the design educational models are radically changing. Today, one of the most impacting evolutions is related to rapid prototyping techniques, which are bringing design practice closer to the auto-production. This emerging trend cannot be anymore supported with traditional didactic approaches, but it is necessary to create spaces for allowing students to learn, design and experiment in a shared way. This paper presents the Polifactory Lab at Politecnico di Milano, an innovative makerspace established with the aim of creating a new research and teaching space. In this paper, the authors present the Polifactory Lab, its theoretical purposes, and some examples of didactic activities carried out in the lab

Augmented Reality to Engage Visitors of Science Museums through Interactive Experiences

In the last years, interactive exhibitions based on digital technologies have become widely common, thanks to their flexibility and effectiveness in engaging visitors and creating memorable experiences. One of the topics in which digital technologies can be particularly effective is the communication of abstract concepts that are difficult for the human mind to imagine. An emblematic example is the astronomy discipline, which requires us to imagine and understand phenomena far away from our everyday life. In this paper, the authors present a research project, MARSS, in which digital technologies are used effectively to enhance the Users' Experience of the Museo Astronomico di Brera located in Milan. Specifically, the MARSS project aims at designing and developing a new digital journey inside the museum to allow different categories of visitors to enjoy the exhibition in an engaging and interactive way. The paper presents the design and development phases of the experience and its evaluation with users. The results of the evaluation indicate that the digital interactive experience is appreciated by users and is successful in translating the content of high scientific value into more engaging and easily understandable elements

Age-associated alterations in cholesterol homeostasis: evidence from a cross-sectional study in a Northern Italy population.

BACKGROUND: The modifications of cholesterol metabolism associated with aging are ill-defined. The objective of this study was to define age-associated alterations of the different metabolic pathways controlling cholesterol homeostasis by analyzing circulating sterols. METHODS: We analyzed serum samples collected from 201 adult (75 male, 126 female) subjects within the epidemiological MICOL study (Multicentrica Italiana Colelitiasi). The age range was 38-79 years; 103 had evidence of gallstones. The concentrations of the different sterols, recognized as markers of the main pathways of cholesterol homeostasis, were analyzed by gas chromatography-mass spectrometry, including lathosterol (synthesis), campesterol and sitosterol (absorption), and 7α-hydroxy-4-cholesten-3-one (degradation to bile acids). RESULTS: A significant direct correlation was detected between age and cholesterol levels (r =0.34, P<0.01). The lathosterol/cholesterol ratio was lower in older age quartiles (P<0.05 by analysis of variance), with an inverse correlation between the lathosterol/cholesterol ratio and age (r=-0.32, P<0.01). Such correlation was particularly evident in females. The campesterol/cholesterol and sitosterol/cholesterol ratios were inversely correlated with aging in control, but not in gallstone patients. The levels of 7α-hydroxy-4-cholesten-3-one were not correlated with age. CONCLUSION: These data show a reduction of cholesterol synthesis with aging which is associated with increased circulating cholesterol levels. The finding might be related to a reduced metabolic need for cholesterol in advancing age, leading to a downregulation of the main mechanisms of cholesterol intake in the liver. A different age-related behavior was observed in gallstone-free versus gallstone patients regarding cholesterol absorption. The possible implications in terms of the pharmacological management of hypercholesterolemia in the elderly remain to be defined

Regulation of ob gene expression: evidence for epinephrine-induced suppression in human obesity

Leptin acts as satiety factor and increases energy expenditure. Studies conducted on animals and in vitro on adipocytes culture have shown that infusion of catecholamines leads to a significant reduction of ob gene expression; it appears of interest to evaluate the in vivo effects of adrenergic activation on the expression of the ob gene in humans. We studied ob gene expression in adipose tissue samples from 13 obese subjects before and after epinephrine (25 ng/min x kg ideal body weight for 3 h) and 6 obese patients during saline infusion. Hormonal infusion led to a significant increase in epinephrine plasma levels (from 27 +/- 4 to 339 +/- 75 pg/mL; P < 0.001), plasma free fatty acids (from 0.73 +/- 0.05 to 0.98 +/- 0.07; P < 0.05), heart rate (13.5 +/- 3.1 beats/min; F = 2.9; P < 0.03), and systolic blood pressure (F = 2.7; P < 0.05), whereas diastolic blood pressure did not show significant variation. Plasma leptin levels decreased by the end of the infusion (from 63 +/- 13 to 49 +/- 11 ng/mL; P < 0.05), and ob messenger ribonucleic acid levels were significantly reduced (decrease amounting to 47 +/- 5% of basal values). Our study shows that adrenergic activation contributes to regulate ob messenger ribonucleic acid levels in humans. The interaction between epinephrine and leptin may operate during metabolic and psychological stress to regulate energy expenditure and food intake

Age-related changes in bile acid synthesis and hepatic nuclear receptor expression

BACKGROUND:Recent data highlighted the role of nuclear receptors in the transcriptional regulation of the limiting enzyme of bile acid synthesis, cholesterol 7alpha-hydroxylase, in cellular and animal models. This study was designed to analyze the effects of age on cholesterol 7alpha-hydroxylase and related nuclear receptor expression in human livers.DESIGN:Surgical liver biopsies were obtained in 23 patients requiring operation on the gastrointestinal tract. mRNA levels of cholesterol 7alpha-hydroxylase and related nuclear receptors and co-activators were assayed by quantitative real-time RT-PCR. Serum levels of 7alpha-hydroxy-4-cholesten-3-one, a marker of bile acid synthesis, were assayed by gas-liquid chromatography:mass spectrometry.RESULTS:Ageing was inversely correlated with serum 7alpha-hydroxy-4-cholesten-3-one and with cholesterol 7alpha-hydroxylase mRNA levels (r = -0.44 and r = -0.45 on a semi-log scale, respectively, P < 0.05). Among different nuclear factors, cholesterol 7alpha-hydroxylase mRNA best correlated with hepatocyte nuclear factor-4 (r = 0.55 on a log scale, P < 0.05); hepatocyte nuclear factor-4 levels were also inversely correlated with age (r = -0.64 on a semi-log scale, P < 0.05). Age was inversely correlated with serum insulin-like growth factor-I levels, which were directly correlated with hepatocyte nuclear factor-4 and cholesterol 7alpha-hydroxylase expression. No suppressive effect of short heterodimer partner expression on cholesterol 7alpha-hydroxylase was observed.CONCLUSIONS:Ageing associates with reduced bile acid synthesis, possibly related to decreased hepatic expression of hepatocyte nuclear factor-4 and consequently of cholesterol 7alpha-hydroxylase. Age-related modifications of the growth hormone/insulin-like growth factor axis might play a role. These findings may help to elucidate the pathophysiology of age-related modifications of cholesterol metabolism

Investigating the effects of odour integration in reading and learning experiences

Books are the tools used for reading novels and stories, but also for educational purposes. Conventional books have undergone a radical transformation in recent years due to the use of new technologies. However, even today the technological devices used for reading e-books are still poorly exploited, despite the fact that they represent a fundamental tool to make the reading experience more immersive by using a complete multisensory approach. In this perspective, one sense that represents an important element of human perception is the sense of smell. Consequently, authors make the hypothesis that the introduction of odours during reading sessions could increase the user experience and the learning performances. In order to demonstrate these hypotheses, the authors have defined and carried out several experimental testing sessions. The analysis of the collected data proved that the introduction of odour does not disturb the reader during reading activities but, on the contrary, can actually make the experience more immersive. Similarly, odours do not disturb studying activities, but they can instead increase the level of concentration and people's learning performance