498 research outputs found
Calibration of tactile/force sensors for grasping with the PRISMA Hand II
The PRISMA Hand II is a mechanically robust anthropomorphic hand developed at PRISMA Lab, University of Naples Federico II. The hand is highly underactuated, three motors drive 19 joints via elastic tendons. Thanks to its particular mechanical design, the hand can perform not only adaptive grasps but also in-hand manipulation. Each fingertip integrates a tactile/force sensor, based on optoelectronic technology, to provide tactile/force feedback during grasping and manipulation, particularly useful with deformable objects. The paper briefly describes the mechanical design and sensor technology of the hand and proposes a calibration procedure for tactile/force sensors. A comparison between different models of Neural Networks architectures, suitable for sensors calibration, is shown. Experimental tests are provided to choose the optimal tactile sensing suite. Finally, experiments for the regulation of the forces are made to show the effectiveness of calibrated sensors
CCD UBV and Gaia DR3 based analysis of NGC 189, NGC 1758 and NGC 7762 open clusters
This paper presents photometric, astrometric, and kinematic analyses of the
open clusters NGC 189, NGC 1758 and NGC 7762 based on CCD UBV photometric and
Gaia Data Release 3 (DR3) data. According to membership analyses, we identified
32, 57 and 106 most probable member stars with membership probabilities in NGC 189, NGC 1758 and NGC 7762, respectively. The color excesses and
photometric metallicities of each cluster were determined separately using UBV
two-color diagrams. The color excess is mag for NGC
189, mag for NGC 1758 and mag for NGC 7762.
The photometric metallicity [Fe/H] is dex for both NGC 189 and
NGC 1758, and dex for NGC 7762. Distance moduli and ages of
the clusters were obtained by comparing PARSEC isochrones with the
color-magnitude diagrams constructed from UBV and Gaia photometric data. During
this process, we kept as constant color excess and metallicity for each
cluster. The estimated isochrone distance is pc for NGC 189, pc for NGC 1758 and pc for NGC 7762. These are compatible
with the values obtained from trigonometric parallax. Ages of the clusters are
Myr, Myr and Myr for NGC 189, NGC 1758
and NGC 7762, respectively. Galactic orbit integration of the clusters showed
that NGC 1758 completely orbits outside the solar circle, while NGC 189 and NGC
7762 enter the solar circle during their orbits.Comment: 25 pages, 11 figures and 6 tables, accepted for publication in
Advances in Space Researc
Bioelectrical impedance analysis in clinical practice: implications for hepatitis C therapy BIA and hepatitis C
<p>Abstract</p> <p>Background</p> <p>Body composition analysis using phase angle (PA), determined by bioelectrical impedance analysis (BIA), reflects tissue electrical properties and has prognostic value in liver cirrhosis. Objective of this prospective study was to investigate clinical use and prognostic value of BIA-derived phase angle and alterations in body composition for hepatitis C infection (HCV) following antiviral therapy.</p> <p>Methods</p> <p>37 consecutive patients with HCV infection were enrolled, BIA was performed, and PA was calculated from each pair of measurements. 22 HCV genotype 3 patients treated for 24 weeks and 15 genotype 1 patients treated for 48 weeks, were examined before and after antiviral treatment and compared to 10 untreated HCV patients at 0, 24, and 48 weeks. Basic laboratory data were correlated to body composition alterations.</p> <p>Results</p> <p>Significant reduction in body fat (BF: 24.2 ± 6.7 kg vs. 19.9 ± 6.6 kg, genotype1; 15.4 ± 10.9 kg vs. 13.2 ± 12.1 kg, genotype 3) and body cell mass (BCM: 27.3 ± 6.8 kg vs. 24.3 ± 7.2 kg, genotype1; 27.7 ± 8.8 kg vs. 24.6 ± 7.6 kg, genotype 3) was found following treatment. PA in genotype 3 patients was significantly lowered after antiviral treatment compared to initial measurements (5.9 ± 0.7° vs. 5.4 ± 0.8°). Total body water (TBW) was significantly decreased in treated patients with genotype 1 (41.4 ± 7.9 l vs. 40.8 ± 9.5 l). PA reduction was accompanied by flu-like syndromes, whereas TBW decline was more frequently associated with fatigue and cephalgia.</p> <p>Discussion</p> <p>BIA offers a sophisticated analysis of body composition including BF, BCM, and TBW for HCV patients following antiviral regimens. PA reduction was associated with increased adverse effects of the antiviral therapy allowing a more dynamic therapy application.</p
Early health technology assessment during nonalcoholic steatohepatitis drug development: a two-round, cross-country, multicriteria decision analysis
Background. The assessment of value along the clinical development of new biopharmaceutical compounds is a challenging task. Complex and uncertain evidence has to be analyzed, considering a multitude of value preferences from different stakeholders. Objective. To investigate the use of multicriteria decision analysis (MCDA) to support decision making during drug development while considering payer and health technology assessment (HTA) value concerns, by applying the Advance Value Framework in nonalcoholic steatohepatitis (NASH) and testing for the consistency of the results. Design. A multiattribute value theory methodology was applied and 2 rounds of decision conferences (DCs) were organized in 3 countries (England, France, and Germany), with the participation of national key experts and stakeholders using the MACBETH questioning protocol and algorithm. A total of 51 health care professionals, patient advocates, and methodologists, including (ex-) committee members or assessors from national HTA bodies, participated in 6 DCs in the study countries. Target Population. NASH patients in fibrosis stages F2 to 3 were considered. Interventions. The value of a hypothetical product profile was assessed against 3 compounds under development using their phase 2 results. Outcome Measures. DC participants’ value preferences were elicited involving criteria selection, options scoring, and criteria weighting. Results. Highly consistent valuation rankings were observed in all DCs, always favoring the same compound. Highly consistent rankings of criteria clusters were observed, favoring therapeutic benefit criteria, followed by safety profile and innovation level criteria. Limitations. There was a lack of comparative treatment effects, early evidence on surrogate endpoints was used, and stakeholder representativeness was limited in some DCs. Conclusions. The use of MCDA is promising in supporting early HTA, illustrating high consistency in results across countries and between study rounds
Sarcoidosis of the Intra- and Extrahepatic Bile Ducts with Concomitant Cholangitis in a Patient with Ulcerative Colitis
Cholangitis in patients with ulcerative colitis (UC) can lead to misdiagnosis of primary sclerosing cholangitis (PSC). Furthermore, it can mimic cholangiocellular carcinoma, which also can lead to inappropriate and potentially harmful treatment of the patient. An 18-year-old male patient with known UC presented with pain in his right upper abdomen and elevation of the cholestatic liver enzymes (alkaline phosphatase: 197 U/L, γ-glutamyltransferase: 229 U/L) and increased inflammatory parameters (leukocytosis and CrP of 13.6 mg/L). Magnetic resonance cholangiopancreatography revealed unclear stenosis in the bifurcation of the main hepatic bile duct as well as in the prepapillary bile duct. Ultrasound (US) examination and endoscopic retrograde cholangiopancreatography showed dilatation of the intra -and extrahepatic bile ducts, which raised the suspicion of PSC. US image with dilated intra- and extrahepatic dilatation of the bile duct was also suggestive for autoimmune cholangitis. However, serum analysis revealed an elevated soluble interleukin-II receptor (1,305 U/mL), while immunoglobulin G4 was within normal ranges. Liver biopsy demonstrated hepatic inflammation and presence of granulomatous cells within the portal fields – convenient to sarcoidosis. After starting treatment with steroids, we observed a rapid clinical response with improvement of the dilated bile ducts and decrease of the initially elevated cholestatic liver enzymes. Sarcoidosis within the bile duct is a rare condition. Steroids are the treatment of choice and – along with the histology – are furthermore helpful to differentiate between several potential differential diagnoses like IgG4 cholangitis, primary biliary cholangitis, or PSC
NLRP3 inflammasome activation is required for fibrosis development in NAFLD
NLR inflammasomes, caspase 1 activation platforms critical for processing key pro-inflammatory cytokines, have been implicated in the development of nonalcoholic fatty liver disease (NAFLD). As the direct role of the NLRP3 inflammasome remains unclear, we tested effects of persistent NLRP3 activation as a contributor to NAFLD development and, in particular, as a modulator of progression from benign hepatic steatosis to steatohepatitis during diet-induced NAFLD. Gain of function tamoxifen-inducible Nlrp3 knock-in mice allowing for in vivo temporal control of NLRP3 activation and loss of function Nlrp3 knockout mice were placed on short-term choline-deficient amino acid-defined (CDAA) diet, to induce isolated hepatic steatosis or long-term CDAA exposure, to induce severe steatohepatitis and fibrosis, respectively. Expression of NLRP3 associated proteins was assessed in liver biopsies of a well-characterized group of patients with the full spectrum of NAFLD. Nlrp3−/− mice were protected from long-term feeding CDAA-induced hepatomegaly, liver injury, and infiltration of activated macrophages. More importantly, Nlrp3−/− mice showed marked protection from CDAA-induced liver fibrosis. After 4 weeks on CDAA diet, wild-type (WT) animals showed isolated hepatic steatosis while Nlrp3 knock-in mice showed severe liver inflammation, with increased infiltration of activated macrophages and early signs of liver fibrosis. In the liver samples of patients with NAFLD, inflammasome components were significantly increased in those patients with nonalcoholic steatohepatitis (NASH) when compared to those with non-NASH NAFLD with mRNA levels of pro-IL1 beta correlated to levels of COL1A1. Our study uncovers a crucial role for the NLRP3 inflammasome in the development of NAFLD. These findings may lead to novel therapeutic strategies aimed at halting the progression of hepatic steatosis to the more severe forms of this disease.Fil: Wree, Alexander. University of California at San Diego; Estados Unidos. University Hospital Essen; AlemaniaFil: McGeough, Matthew D.. University of California at San Diego; Estados UnidosFil: Peña, Carla A.. University of California at San Diego; Estados UnidosFil: Schlattjan, Martin. University Hospital Essen; AlemaniaFil: Li, Hongying. University of California at San Diego; Estados UnidosFil: Inzaugarat, Maria Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Inmunología, Genética y Metabolismo. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Inmunología, Genética y Metabolismo; ArgentinaFil: Messer, Karen. University of California at San Diego; Estados UnidosFil: Canbay, Ali. University Hospital Essen; AlemaniaFil: Hoffman, Hal M.. University of California at San Diego; Estados Unidos. Ludwig Institute of Cancer Research; Estados UnidosFil: Feldstein, Ariel E.. University of California at San Diego; Estados Unido
Changes in the expression of plasma membrane calcium extrusion systems during the maturation of hippocampal neurons
Spatial and temporal control of intracellular calcium signaling is essential for neuronal development and function. The termination of local Ca2+ signaling and the maintenance of basal Ca2+ levels require specific extrusion systems in the plasma membrane. In rat hippocampal neurons developing in vitro, transcripts for all isoforms of the plasma membrane Ca2+ pump (PMCA) and the Na/Ca2+ exchanger (NCX), and the major non-photoreceptor Na+/Ca2+,K+ exchangers (NCKX) were strongly upregulated during the second week in culture. Upregulation of PMCA1, 3, and 4 mRNA coincided with a splice shift from the ubiquitous b-type to the neuron-specific a-type with altered calmodulin regulation. Expression of all PMCA isoforms increased over five-fold during the first two weeks. PMCA immunoreactivity was initially concentrated in the soma and growth cones of developing hippocampal neurons. As the cells matured, PMCAs concentrated in the dendritic membrane and often co-localized with actin-rich dendritic spines in mature neurons. In the developing rat hippocampal CA1 region, immunohistochemistry confirmed the upregulation of all PMCAs and showed that by the end of the second postnatal week, PMCAs 1, 2 and 3 were concentrated in the neuropil, with less intense staining of cell bodies in the pyramidal layer. PMCA4 staining was restricted to a few cells showing intense labeling of the cell periphery and neurites. These results establish that all major Ca2+ extrusion systems are strongly upregulated in hippocampal neurons during the first two weeks of postnatal development. The overall increase in Ca2+ extrusion systems is accompanied by changes in the expression and cellular localization of different isoforms of the Ca2+ pumps and exchangers. The accumulation of PMCAs in dendrites and dendritic spines coincides with the functional maturation in these neurons, suggesting the importance of the proper spatial organization of Ca2+ extrusion systems for synaptic function and development
Inhibition of focal adhesion kinase with her-2 targeted antibody pertuzumab (Omnitarg®, 2C4) in breast cancer cells
Pertuzumab (Omnitarg®, 2C4) is a recombinant humanized monoclonal antibody targeted to extracellular region of HER-2. Previous results proved the inhibitory effect of Pertuzumab on the survival of breast cancer cells via MAPK and Akt pathway. Focal adhesion kinase (FAK) regulates multiple cellular processes including growth, differentiation, adhesion, motility and apoptosis. Here, we aimed to investigate the effects of Pertuzumab on ligand activated total FAK expression and phosphorylation in the HER-2 overexpressing BT-474 breast cancer cell line. Heregulin was used for ligand activation. We have found that FAK expression and phosphorylation were inhibited in with Pertuzumab in breast cancer cells
Combined activities of JNK1 and JNK2 in hepatocytes protect against toxic liver injury
Background & Aims: c-Jun N-terminal kinase (JNK)1 and JNK2 are expressed in hepatocytes and have overlapping and distinct functions. JNK proteins are activated, via phosphorylation, in response to acetaminophen- or CCl4-induced liver damage; the level of activation correlates with the degree of injury. SP600125, a JNK inhibitor, has been reported to block acetaminophen-induced liver injury. We investigated the role of JNK in drug-induced liver injury (DILI) in liver tissues from patients and in mice with genetic deletion of JNK in hepatocytes. Methods: We studied liver sections from patients with DILI (due to acetaminophen, phenprocoumon, non-steroidal anti-inflammatory drugs or autoimmune hepatitis), or patients without acute liver failure (controls), collected from a DILI Biobank in Germany. Levels of total and activated (phosphorylated) JNK were measured by immunohistochemistry and western blotting. Mice with hepatocyte-specific deletion ofJnk1 (Jnk1Δhepa) or combination of Jnk1 and Jnk2 (JnkΔhepa), as well as Jnk1-floxed C57BL/6 (control) mice, were given injections of CCl4 (to induce fibrosis) or acetaminophen (to induce toxic liver injury). We performed gene expression microarray, and phosphoproteomic analyses to determine mechanisms of JNK activity in hepatocytes. Results: Liver samples from DILI patients contained more activated JNK, predominantly in nuclei of hepatocytes and in immune cells, than healthy tissue. Administration of acetaminophen to JnkΔhepa mice produced a greater level of liver injury than that observed in Jnk1Δhepa or control mice, based on levels of serum markers and microscopic and histologic analysis of liver tissues. Administration of CCl4 also induced stronger hepatic injury in JnkΔhepa mice, based on increased inflammation, cell proliferation, and fibrosis progression, compared to Jnk1Δhepa or control mice. Hepatocytes from JnkΔhepamice given acetaminophen had an increased oxidative stress response, leading to decreased activation of AMPK, total protein AMPK levels, and pJunD and subsequent necrosis. Administration of SP600125 before or with acetaminophen protected JnkΔhepaand control mice from liver injury. Conclusions: In hepatocytes, JNK1 and JNK2 appear to have combined effects in protecting mice from CCl4- and acetaminophen-induced liver injury. It is important to study the tissue-specific functions of both proteins, rather than just JNK1, in the onset of toxic liver injury. JNK inhibition with SP600125 shows off-target effects
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