Water-based spider silk films

Spider silk proteins represent exceptional natural polymers due to their mechanical properties in combination with biocompatibility. As both hydrophobic and slowly biodegrading biopolymers, recombinant spider silk proteins fulfill the required properties for a drug delivery system. The recombinant production of spider silk proteins allows the cost-effective fabrication of these biopolymers. The main focus of this thesis was to obtain a reproducible all-aqueous protein film production process in order to cast spider silk films characterized by biocompatibility, water insolubility and good mechanical properties. The evaluation of spider silk films as novel carrier for various pharmaceuticals was also part of this work. Ideally, the film preparation process has to be compatible with protein encapsulation and the obtained matrix should be able to release a therapeutic protein for a prolonged time

Comparison of IMU set-ups for the estimation of gait spatio-temporal parameters in an elderly population

The increasing average age emphasizes the importance of gait analysis in elderly populations. Inertial Measurement Units (IMUs) represent a suitable wearable technology for the characterization of gait by estimating spatio-temporal parameters (STPs). However, the location of inertial sensors on the human body and the associated algorithms for the estimation of gait STPs play a fundamental role and are still open challenges. Accordingly, the aim of this work was to compare three IMUs set-ups (trunk, shanks, and ankles) and correspondent algorithms to a gold standard optoelectronic system for the estimation of gait STPs in a healthy elderly population. In total, 14 healthy elderly subjects walked barefoot at three different speeds. Gait parameters were assessed for each IMUs set-up and compared to those estimated with the gold standard. A statistical analysis based on Pearson correlation, Root Mean Square Error and Bland Altman plots was conducted to evaluate the accuracy of IMUs. Even though all tested set-ups produced accurate results, the IMU on the trunk performed better in terms of correlation (R ≥ 0.8), RMSE (0.01-0.06 s for temporal parameters, 0.03-0.04 for the limp index), and level of agreement (-0.01 s ≤ mean error ≤ 0.01 s, -0.02 s ≤ standard deviation error ≤ 0.02 s), also allowing simpler preparation of subjects and minor encumbrance during gait. From the promising results, a similar experiment might be conducted in pathological populations in the attempt to verify the accuracy of IMUs set-ups and algorithms also in non-physiological patterns

Water-based spider silk films

Spider silk proteins represent exceptional natural polymers due to their mechanical properties in combination with biocompatibility. As both hydrophobic and slowly biodegrading biopolymers, recombinant spider silk proteins fulfill the required properties for a drug delivery system. The recombinant production of spider silk proteins allows the cost-effective fabrication of these biopolymers. The main focus of this thesis was to obtain a reproducible all-aqueous protein film production process in order to cast spider silk films characterized by biocompatibility, water insolubility and good mechanical properties. The evaluation of spider silk films as novel carrier for various pharmaceuticals was also part of this work. Ideally, the film preparation process has to be compatible with protein encapsulation and the obtained matrix should be able to release a therapeutic protein for a prolonged time

Gait Phases Detection in Elderly using Trunk-MIMU System

The increasing interest towards wearable Magnetic Inertial Measurement Units (MIMUs) for gait analysis is justified by their low invasiveness, confirmed repeatability and complete independence from laboratory constraints. However, some crucial doubts about the identification of a suitable sensor set-up and algorithm in different gait conditions and populations still exist. In this context, the principal aim of the present study was to investigate the effect of different walking conditions on the accuracy of gait phases detection with a trunk-MIMU system. Eleven healthy elderly subjects performed gait trials in four different walking conditions (fast speed, normal speed, slow speed and normal speed with dual-task). A stereophotogrammetric system was adopted as gold standard. The accuracy of the estimation of stance and swing phases was evaluated from the comparison of trunk-MIMU to the stereophotogrammetric system. Mean error values smaller than 0.03 s confirmed the accuracy of the tru nk-MIMU algorithm for an elderly population. Consequently, trunk-MIMU system can be considered suitable for the characterization of gait phases in elderly subjects regardless of walking conditions

New Constraints on Supersymmetry Using Neutrino Telescopes

We demonstrate that megaton-mass neutrino telescopes are able to observe the signal from long-lived particles beyond the Standard Model, in particular the stau, the supersymmetric partner of the tau lepton. Its signature is an excess of charged particle tracks with horizontal arrival directions and energy deposits between 0.1 and 1 TeV inside the detector. We exploit this previously-overlooked signature to search for stau particles in the publicly available IceCube data. The data shows no evidence of physics beyond the Standard Model. We derive a new lower limit on the stau mass of $320$ GeV (95\% C.L.) and estimate that this new approach, when applied to the full data set available to the IceCube collaboration, will reach world-leading sensitivity to the stau mass ($m_{\tilde{\tau}}=450\,\mathrm{GeV}$)

A challenging case of fever of unknown origin (FUO)

Introduction. Fever of unknown origin (FUO) is challenging for physicians as there are more than 200 differential diagnosis of FUO. The diagnosis often requires numerous non-invasive and invasive procedures and sometimes the etiology remains unknown. Clinical case. Our patient is a 24-year-old Caucasian female under contraceptive vaginal ring treatment who presented the first time to the emergency department with fever (38,5°C) and stomach ache. Haematological parameters showed thrombocytosis (728000/mmc) and anemia (10,2 g/dl). Ultrasonography of the abdomen revealed a 4 cm hepatic angioma. She was diagnosed a gastropathy and treated with PPI. Then she was studied deeper because of elevated inflammation markers, persistent thrombocytosis and low-grade fewer combined with fatigue and stomach ache. Despite multiple blood and urine cultures, serology, autoimmune serology, bone marrow biopsy, echocardiography, PET/CT, total body CT, brain MRI scan, transvaginal sonography and gynecological examination no clinical focus could be identified. Esophagogastroduodenoscopy was negative but the histological examination was suggestive of mild celiac disease. Thus, this diagnosis was unlikely because serologic tests and haplotypes DQ2 and DQ8 were negative. Abdomen RMI was suggestive of a 4 cm hepatic adenoma. After surgical resection of the adenoma platelet count normalized and fever disappeared. Conclusions. Hepatic adenoma is an uncommon liver tumor associated with use of oral contraceptive and can be a rare cause of FUO. MRI scan can be a useful tool to detect this tumor

Expression of circadian clock genes and diurnal oscillations of key physiological events in response to AsV and AsIII in soybean plants

Soybean (Glycine max L.) is often cultivated in soils with a high content of arsenic (As). Since this greatly affects crop growth and yield, the response mechanisms underlying tolerance to As should be well understood. Circadian rhythms are known to play a central role in plant adaptation to stressful conditions. Therefore, our aim was to evaluate the effects of arseniate (AsV) and arsenite (AsIII) on the expression of key circadian clock genes (CG) and on the possible diurnal oscillation of physiological events induced by As in soybean plants. Leaves and roots were evaluated during light-dark phases at 4-h intervals. The changes caused by As in the expression profiles of all CGs analyzed depended on its chemical form and the plant organ involved. Overexpression of GmLCL1, GmTOC1, GmPRR9 and GmGI was observed in leaves mainly upon AsV-treatment, while underexpression of GmLCL1 and overexpression of GmPRR9, GmELF4 and GmGI occurred in roots, mainly upon AsIII-treatment. Moreover, As seemed to have an influence on the daily fluctuations observed in events triggered in response to the stress, such as stomatal aperture control, phytochelatin (PC) and glutathione (GSH) content, and total antioxidant, ascorbate (APx) and glutathione peroxidase (GPx) activities. In particular, the increase in the synthesis of PCs (the main As chelators) and the decrease in their precursor, GSH, were higher during the light phase, while APx and GPx activities increased during the dark phase in As-treated plants. The results suggest a link between the circadian clock and the response to As in soybean plants, since exposure to As modified CG expression and induced important changes in the diurnal oscillation of several As-response mechanisms. Circadian clock regulation, then, might play a vital role in the tolerance to As.Fil: Vezza, Mariana Elisa. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Biotecnología Ambiental y Salud - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Biotecnología Ambiental y Salud; ArgentinaFil: Sosa Alderete, Lucas Gastón. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Biotecnología Ambiental y Salud - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Biotecnología Ambiental y Salud; ArgentinaFil: Agostini, Elizabeth. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Biotecnología Ambiental y Salud - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Biotecnología Ambiental y Salud; ArgentinaFil: Talano, Melina Andrea. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Biotecnología Ambiental y Salud - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Biotecnología Ambiental y Salud; Argentin

Micromechanical characterization of spider silk particles

Spider silk fibers are well known for their mechanical properties, and they are therefore in the focus of materials scientists. Additionally, silks display biocompatibility making them interesting materials for applications in medicine or cosmetics. Due to the low abundance of natural spider silk proteins because of the spider's cannibalism, the recombinant spider silk protein eADF4 has been established for material science applications. Once processed into micron-sized particles by controlled salting-out, these particles can be used as drug delivery vehicles. For any application of the silk particles it is important to know their mechanical characteristics for processing and storage reasons. Here, we examine the swelling behavior and mechanics of these particles. Upon hydration, a drastic drop in elastic modulus occurs by orders of magnitude, from 0.8 GPa in the dry state to 2.99 MPa in the wet state. Importantly, the elastic modulus of recombinant silk particles can be tuned by varying the molecular weight of the used proteins, as well as chemical crosslinking thereof

Procalcific Phenotypic Drift of Circulating Progenitor Cells in Type 2 Diabetes with Coronary Artery Disease

Diabetes mellitus (DM) alters circulating progenitor cells relevant for the pathophysiology of coronary artery disease (CAD). While endothelial progenitor cells (EPCs) are reduced, there is no data on procalcific polarization of circulating progenitors, which may contribute to vascular calcification in these patients. In a cohort of 107 subjects with and without DM and CAD, we analyzed the pro-calcific versus endothelial differentiation status of circulating CD34+ progenitor cells. Endothelial commitment was determined by expression of VEGFR-2 (KDR) and pro-calcific polarization by expression of osteocalcin (OC) and bone alkaline phosphatase (BAP). We found that DM patients had significantly higher expression of OC and BAP on circulating CD34+ cells than control subjects, especially in the presence of CAD. In patients with DM and CAD, the ratio of OC/KDR, BAP/KDR, and OC+BAP/KDR was about 3-fold increased than in other groups. EPCs cultured from DM patients with CAD occasionally formed structures highly suggestive of calcified nodules, and the expression of osteogenic markers by EPCs from control subjects was significantly increased in response to the toll-like receptor agonist LPS. In conclusion, circulating progenitor cells of diabetic patients show a phenotypic drift toward a pro-calcific phenotype that may be driven by inflammatory signals