1,347 research outputs found
A preclinical model for the ATLL lymphoma subtype with insights into the role of microenvironment in HTLV-1-mediated lymphomagenesis
Abstract
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Adult T cell Leukemia/Lymphoma (ATLL) is a mature T cell malignancy associated with Human T cell Leukemia Virus type 1 (HTLV-1) infection. Among its four main clinical subtypes, the prognosis of acute and lymphoma variants remains poor. The long latency (3-6 decades) and low incidence (3-5%) of ATLL imply the involvement of viral and host factors in full-blown malignancy. Despite multiple preclinical and clinical studies, the contribution of the stromal microenvironment in ATLL development is not yet completely unraveled. The aims of this study were to investigate the role of the host microenvironment, and specifically fibroblasts, in ATLL pathogenesis and to propose a murine model for the lymphoma subtype. Here we present evidence that the oncogenic capacity of HTLV-1-immortalized C91/PL cells is enhanced when they are xenotransplanted together with human foreskin fibroblasts (HFF) in immunocompromised BALB/c Rag2-/-\u3b3c -/-mice. Moreover, cell lines derived from a developed lymphoma and their subsequent in vivo passages acquired the stable property to induce aggressive T cell lymphomas. In particular, one of these cell lines, C91/III cells, consistently induced aggressive lymphomas also in NOD/SCID/IL2R\u3b3c KO (NSG) mice. To dissect the mechanisms linked to this enhanced tumorigenic ability, we quantified 45 soluble factors released by these cell lines and found that 21 of them, mainly pro-inflammatory cytokines and chemokines, were significantly increased in C91/III cells compared to the parental C91/PL cells. Moreover, many of the increased factors were also released by human fibroblasts and belonged to the known secretory pattern of ATLL cells. C91/PL cells co-cultured with HFF showed features reminiscent of those observed in C91/III cells, including a similar secretory pattern and a more aggressive behavior in vivo. On the whole, our data provide evidence that fibroblasts, one of the major stromal components, might enhance tumorigenesis of HTLV-1-infected and immortalized T cells, thus throwing light on the role of microenvironment contribution in ATLL pathogenesis. We also propose that the lymphoma induced in NSG mice by injection with C91/III cells represents a new murine preclinical ATLL model that could be adopted to test novel therapeutic interventions for the aggressive lymphoma subtype
Effect of intranasal NGF administration in injured spinal cord and leptin levels in adult rats
Spinal cord injury alters a number of endogenous biological signals known to be involved in the modulation of neurotrophic and neuroprotective events. Nerve growth factor (NGF) is a neurotrophic factor expressed in neuronal and non-neuronal tissues including spinal cord, and increases after spinal cord injury. Recent findings revealed that leptin, an adipocyte-derived cytokine (adipokine), enhance neuronal survival and exert neuroprotective action, and played an important role in nociceptive behavior induced by nerve injury. Whether NGF affects the expression of leptin in injured spinal cord has not been investigated. The present study was designed to evaluate: (i) whether intranasal NGF administration reached the spinal cord of the rat, (ii) if NGF affects the expression of leptin in the spinal cord and adipose tissue, and (iii) whether intranasal NGF affects the behavioral and spinal cord neuronal deficits induced by spinal cord injury. The result showed that intranasal NGF enhances the expression of (i) NGF and NGF-receptors (TrkA and p75NTR) in injured spinal cord exerting behavioral and neuroprotective action, and (ii) leptin in injured spinal cord and in subcutaneous (white) and interscapular (brown) adipose tissue. Altogether, the present data demonstrate the efficacy of intranasal administration of NGF, and suggest a link between the neurotrophin NGF and the adipokine leptin that may be therapeutically explored in injured spinal cord.Adipobiology 2012; 4: 67-75
Quality of life in post-menopausal osteoporosis
BACKGROUND: To evaluate the impact of osteoporosis on the patients' quality of life, particularly in the absence of fractures. METHODS: 100 post-menopausal women (age 50-85) - 62 with uncomplicated primary osteoporosis and 38 with primary osteoporosis complicated by vertebral fractures; all already treated - were studied using two validated questionnaires: Qualeffo-41 for quality of life in osteoporosis, and Zung for depression. Data were compared to those of 35 controls of comparable age, affected by a different chronic disease (hypothyroidism). RESULTS: Family history of osteoporosis and T-score of spine were similar in the two subgroups of osteoporotic women. Body mass index, age at menopause and education level were similar in the two subgroups of osteoporotic women and in the control group. The patients affected by osteoporosis perceived it as a disease affecting their personal life with undesirable consequences: chronic pain (66% of women with fractures and 40% of women without fractures), impaired physical ability, reduced social activity, poor well-being (21% of women without fractures) and depressed mood (42% of women irrespective of fractures). Overall, 41% of the women showed a reduced quality of life. On the contrary, in the control group only 11% reported a reduced quality of life. CONCLUSION: The quality of life of osteoporotic patients should be investigated even before fractures, in order to develop appropriate counselling, support and care interventions to help patients develop efficient strategies for accepting the disease and coping with it
Mitochondrial Complex I: Structural and functional aspects
AbstractThis review examines two aspects of the structure and function of mitochondrial Complex I (NADH Coenzyme Q oxidoreductase) that have become matter of recent debate. The supramolecular organization of Complex I and its structural relation with the remainder of the respiratory chain are uncertain. Although the random diffusion model [C.R. Hackenbrock, B. Chazotte, S.S. Gupte, The random collision model and a critical assessment of diffusion and collision in mitochondrial electron transport, J. Bioenerg. Biomembranes 18 (1986) 331–368] has been widely accepted, recent evidence suggests the presence of supramolecular aggregates. In particular, evidence for a Complex I–Complex III supercomplex stems from both structural and kinetic studies. Electron transfer in the supercomplex may occur by electron channelling through bound Coenzyme Q in equilibrium with the pool in the membrane lipids. The amount and nature of the lipids modify the aggregation state and there is evidence that lipid peroxidation induces supercomplex disaggregation. Another important aspect in Complex I is its capacity to reduce oxygen with formation of superoxide anion. The site of escape of the single electron is debated and either FMN, iron–sulphur clusters, and ubisemiquinone have been suggested. The finding in our laboratory that two classes of hydrophobic inhibitors have opposite effects on superoxide production favours an iron–sulphur cluster (presumably N2) is the direct oxygen reductant. The implications in human pathology of better knowledge on these aspects of Complex I structure and function are briefly discussed
Cystic fibrosis bone disease: Pathophysiology, assessment and prognostic implications.
Cystic fibrosis bone disease (CFBD) is a common long-term complication of cystic fibrosis (CF) that can lead to increased fractures and significant morbidity and mortality in this patient population. CFBD pathophysiology remains poorly understood and is likely to be multifactorial. There are limited studies evaluating diagnostic tools and tests to guide therapeutic decisions and monitoring of CFBD. This review will present and discuss the current evidence
Capsaicin-induced corneal sensory denervation and healing impairment are reversed by NGF treatment.
PURPOSE. We aimed to evaluate the nerve growth factor (NGF) pathway and its influence on corneal healing mechanisms in normal conditions and in an animal model of corneal denervation induced by capsaicin. METHODS. Peripheral sensory damage was induced in rat pups by subcutaneous injection of capsaicin and the effects evaluated by hot-plate test, corneal nerve count, and tear secretion. Corneal damage was induced in capsaicin-treated and -untreated rats by epithelial scraping. Healing rate; NGF pathway (NGF, tyrosine kinase A [TrkA], p75); and the stem cell marker p63 were evaluated by RT-PCR, ELISA, Western blot, and immunohistochemistry. The effects of exogenous NGF administration as eye drop formulation were also tested. RESULTS. Capsaicin treatment induced a significant reduction of peripheral sensitivity, corneal innervation, tear secretion, and corneal healing rate. The ocular effects of capsaicin treatment were associated with an NGF pathway alteration. NGF eye drop treatment aided corneal healing mechanisms through a significant increase in the NGF receptors TrkA and p75, and in the stem cell marker p63. CONCLUSIONS. In this study, we show that an alteration in the NGF pathway is responsible for a delay in corneal healing in an animal model of sensory denervation. Moreover, we show that NGF eye drop administration modulates corneal innervation, epithelial cell healing, and corneal stem cells. These findings may trigger further research on the role of the NGF pathway in limbal stem cell deficiency. (Invest Ophthalmol Vis Sci. 2012; 53:8280‐8287) DOI:10.1167/iovs.12-1059
An internet-based approach for lifestyle changes in patients with NAFLD: Two-year effects on weight loss and surrogate markers
Background & Aims Interventions aimed at lifestyle changes are pivotal for the treatment of non-alcoholic fatty liver disease (NAFLD), and web-based programs might help remove barriers in both patients and therapists. Methods In the period 2010–15, 716 consecutive NAFLD cases (mean age, 52; type 2 diabetes, 33%) were treated in our Department with structured programs. The usual protocol included motivational interviewing and a group-based intervention (GBI), chaired by physicians, dietitians and psychologists (five weekly meetings, n = 438). Individuals who could not attend GBI entered a web-based intervention (WBI, n = 278) derived from GBI, with interactive games, learning tests, motivational tests, and mail contacts with the center. The primary outcome was weight loss ≥10%; secondary outcomes were alanine aminotransferase within normal limits, changes in lifestyle, weight, alanine aminotransferase, and surrogate markers of steatosis and fibrosis. Results GBI and WBI cohorts had similar body mass index (mean, 33 kg/m2), with more males (67% vs. 45%), younger age, higher education, and more physical activity in the WBI group. The two-year attrition rate was higher in the WBI group. Healthy lifestyle changes were observed in both groups and body mass index decreased by almost two points; the 10% weight target was reached in 20% of WBI cases vs. 15% in GBI (not significant). In logistic regression analysis, after adjustment for confounders and attrition rates, WBI was not associated with a reduction of patients reaching short- and long-term 10% weight targets. Liver enzymes decreased in both groups, and normalized more frequently in WBI. Fatty liver index was reduced, whereas fibrosis remained stable (NAFLD fibrosis score) or similarly decreased (Fib-4). Conclusion WBI is not less effective than common lifestyle programs, as measured by significant clinical outcomes associated with improved histological outcomes in NAFLD. eHealth programs may effectively contribute to NAFLD control. Lay summary In patients with non-alcoholic fatty liver disease, participation in structured lifestyle programs may be jeopardized by job and time constraints. A web-based intervention may be better suited for young, busy patients, and for those living far from liver units. The study shows that, following a structured motivational approach, a web-based, interactive intervention coupled with six-month face-to-face meetings is not inferior to a standard group-based intervention with respect to weight loss, adherence to healthy diet and habitual physical activity, normalization of liver enzymes, and stable surrogate markers of fibrosis
Bringing social interaction at the core of organizational neuroscience
Organizations are composed of individuals working together for achieving specific goals, and interpersonal dynamics do exert a strong influence on workplace behaviour. Nevertheless, the dual and multiple perspective of interactions has been scarcely considered by Organizational Neuroscience (ON), the emerging field of study that aims at incorporating findings from cognitive and brain sciences into the investigation of organizational behaviour. This perspective article aims to highlight the potential benefits of adopting experimental settings involving two or more participants (the so-called "second person" approach) for studying the neural bases of organizational behaviour. Specifically, we stress the idea that moving beyond the individual perspective and capturing the dynamical relationships occurring within dyads or groups (e.g., leaders and followers, salespersons and clients, teams) might bring novel insights into the rising field of ON. In addition, designing research paradigms that reliably recreate real work and life situations might increase the generalizability and ecological validity of its results. We start with a brief overview of the current state of ON research and we continue by describing the second-person approach to social neuroscience. In the last paragraph, we try and outline how this approach could be extended to ON. To this end, we focus on leadership, group processes and emotional contagion as potential targets of interpersonal ON research
BlogDidattici, una storia a più voci
Un blog è molto spesso un’isola, uno spazio privato nel quale l’autore racconta se stesso, uno strumento poco idoneo per essere utilizzato in didattica. La scommessa di BlogDidattici è stata quella di fare del blog un ambiente di apprendimento cooperativo. La storia di BlogDidattici è un racconto a più voci di esperienze formative personali che si intrecciano tra il virtuale e il reale
An in vitro strategy to assess mitigation of hazardous properties of engineered metal nanoparticles
The huge progress in the nanotechnology field has requested the production of increasingly
advanced engineered nanoparticles (NPs). In particular, metal-based advanced NPs are
widely used in several industrial applications. However, their potential effects on human
health during occupational exposure are still incompletely characterized thus far and
possible strategies to decrease their hazardous properties are not yet clearly defined. In this
project we are developing an in vitro approach to test the cytotoxic effects of metal-based
NPs, as derived from production lines or modified through coating with organic or inorganic
moieties. We have used two cell models widely employed in toxicological studies, the human
alveolar cell line A549 and the murine macrophage cell line RAW264.7, to avoid possible
limitations due to cell specific effects. Moreover, in order to evaluate the effectiveness of
mitigation approaches for NPs endowed with little acute cytotoxicity, additional endpoints,
alternative to viability, have also been assessed. Colloidal suspensions of Ag, TiO2 and ZrO2
NPs were tested as provided by industries or modified with SiO2 NPs or citrate used as
coating remediation agents. Heterocoagulation of opposite charged phases was applied in
order to promote the coating of pristine surfaces by modifying agents. Heterocoagulated sols
were obtained by ball milling sols of positive charged Ag, TiO2 and ZrO2 NPs with negative
charged SiO2 NPs or citrate ions. Modified samples, obtained by spray-drying and re-
dispersing in water the corresponding sols, were also obtained in order to compare
reactivity. Original and modified NPs were added to culture media starting from water
colloidal suspensions. Viability was determined with the resazurin method in a range of
doses from 2.5 to 80 nfg/cm2 (0.3125 to 20 g/cm2 for Ag NPs) of monolayer surface at three
experimental times (24, 48 and 72h). The expression of the inducible form of nitric oxide
synthase (Nos2), an indicator of macrophage activation and, hence, of pro-inflammatory
activity, was assessed with RT-PCR as an end-point alternative to viability.
Among the NPs tested, only Ag NP caused a significant loss of viability, with an IC50 of about
0.8 g/cm2 for Raw264.7 cells and 2.4 g/cm2 for A549 cells at the 24h-experimental time. In
a preliminary experiment, SiO2 NPs were demonstrated to have no significant effect on cell
viability. The comparison between original and SiO2-coated Ag NPs, performed in the same
experiment, suggested a coating-independent mitigation effect of bioreactivity exerted by the
spray drying procedure. However, once corrected for the actual Ag content of the spray-
dried powder, no significant difference was found in the IC50 values, indicating that neither
silica coating nor spray drying mitigate cytotoxicity. The effects on viability of original TiO2
and ZrO2 NPs were assessed using P25 Aeroxide TiO2 NPs as a reference material. These
materials did not affect significantly cell viability at any time point tested, so that it was not
possible to estimate IC50 values for either cell line. However, titania produced a clear-cut
induction of Nos2 expression in Raw264.7 cells, thus indicating their potential pro-
inflammatory activity. Citrate coating did not produce any significant attenuation of the
biological effect. In summary, these preliminary results showed no mitigating effect of the
surface modifications tested on the biological effects of the engineered NPs investigated.
However, the exploitation of this in vitro experimental strategy can be useful for the
preliminary assessment of the mitigation potential of surface modifications of both low-toxic
and high-toxic engineered NPs.
Supported by EU Grant NMP4-SL-2012-280716 (Sanowork Project
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