The role of nanopatterning in cell and nuclear mechanics

Biophysical signals are known to influence cell fate and functions. In particular, topographic cues exert a direct control over focal adhesions positioning and cytoskeletal assemblies. Moreover, the nuclear envelope is directly connected to the cytoskeleton and actin generated stresses can directly impact on nuclear shape and gene matter configuration. However, how topographic patterns might influence the processes above or more generally, cellular and nuclear mechanics is still unclear. The goal of this work is to investigate how the microenvironmental conditions in terms of topographic cues, substrate chemistry and cell-cell contacts may alter the cell morphology, along with cellular and nuclear mechanics. In a first set of experiments we used nanopatterned polydimethylsiloxane (PDMS) as cell culturing substrates. The patterns consisted of parallel and straight channels having ridge to groove width ratio of 1:1. Pattern features used were 700nm or 350 nm wide with depth of 250nm or 100nm respectively. Additionally, the chemistry of the material surface was modified by performing different functionalization treatments, namely fibronectin or serum coating. Mesenchymal Stem Cells (hMSC) were cultured at low densities on the substrates up to 48h. Atomic Force Microscopy (AFM) was employed to generate elasticity maps of the whole cell body. We then correlated local elastic modulus with cell height in order to discriminate the different cellular regions. Our analysis showed structural and mechanical heterogeneity of the cell body, clearly mediated by topographic and adhesive signal. In particular, the spindle like phenotype observed on the nanopatterned materials generates compressive forces on the nucleus, which increase its mechanical properties. Our results also demonstrated a positive correlation between the expression of lamins A / C, the structural proteins of the nucleus, and the mechanical properties of the nuclear region. Therefore it is reasonable to hypothesize that these proteins have a primary role in dictating the mechanical properties of the nucleus. In a second setup, we used endothelial cells (HUVECs) on flat PDMS substrates to investigate the effect of cell-cell contacts on cytoskeletal assembly and nuclear mechanics. We found that actin is redistributed in the cortical area, freeing the nucleus, which exhibits a mechanical conformation characterized by lower moduli than single cells. Our results pave the way for capturing designing concept to fabricate novel patterned platforms that effectively alters nuclear mechanics and possibly cell fate by tuning the material-cytoskeleton-nucleus crosstalk

Soil quality of a degraded urban area

Human activities cause modifications of the soil characteristics, leading to a significant reduction of the soil fertil- ity and quality. The aim of this study was to evaluate the relationships between microbial activity or biomass and chemical char- acteristics (i.e. heavy metal and organic matter contents) of a degraded urban soil. The study area is located in an urban park (about 10 ha, called Quarantena) near to the Fusaro Lake of Campi Fle- grei (Southern Italy); the Park was established in 1953 to shelter animals coming from any place of the Planet and execute veterinary checks before their delivery to different European zoos. In 1997, the park was abandoned and nowadays in it a large amount of urban wastes accumulates. Surface soils (0-10 cm) were sampled at three points: two of them covered by Holm Oak specimens (P1 and P2) and one covered by herbaceous species, particularly legumes (P3). P1 was localized at the border of the park and next to a busy road; P2 at the centre of the Quarantena Park; P3 at a gap area near the Fusaro Lake. The results showed that the soil sampled at P1 showed the highest Cr and Ni concentrations; the soil sampled at P3 had high levels of Cu and Pb, exceeding the threshold values of 100 μg g-1 d.w. fixed by the Italian law for urban soils, probably due to boat traffic, fishing practice and agricultural activities; the soil sampled at P2 had interme- diate values of metal concentrations but the highest amount of organic matter (more than 20% d.w.). Despite of metal contamination, P1 and P3 showed higher soil microbial biomass and activity as compared to P2. Therefore, at this site, the organic matter accumulation could be due to the scarce litter degradation. In conclusion, although the studied area was not too large, a wide heterogeneity of soil quality (in terms of the investigated chemical and biological characteristics) was detected, depending on the local human impact

Energy metabolism and the skeleton: Reciprocal interplay

The relation between bone remodelling and energy expenditure is an intriguing, and yet unexplained, challenge of the past ten years. In fact, it was only in the last few years that the skeleton was found to function, not only in its obvious roles of body support and protection, but also as an important part of the endocrine system. In particular, bone produces different hormones, like osteocalcin (OC), which influences energy expenditure in humans. The undercarboxylated form of OC has a reduced affinity for hydroxyapatite; hence it enters the systemic circulation more easily and exerts its metabolic functions for the proliferation of pancreatic β-cells, insulin secretion, sensitivity, and glucose tolerance. Leptin, a hormone synthesized by adipocytes, also has an effect on both bone remodelling and energy expenditure; in fact it inhibits appetite through hypothalamic influence and, in bone, stimulates osteoblastic differentiation and inhibits apoptosis. Leptin and serotonin exert opposite influences on bone mass accrual, but several features suggest that they might operate in the same pathway through a sympathetic tone. Serotonin, in fact, acts via two opposite pathways in controlling bone remodelling: central and peripheral. Serotonin product by the gastrointestinal tract (95%) augments bone formation by osteoblast, whereas brain-derived serotonin influences low bone mineral density and its decrease leads to an increase in bone resorption parameters. Finally, amylin (AMY) acts as a hormone that alters physiological responses related to feeding, and plays a role as a growth factor in bone. In vitro AMY stimulates the proliferation of osteoblasts, and osteoclast differentiation. Here we summarize the evidence that links energy expenditure and bone remodelling, with particular regard to humans

Non-arthritic Hip Score: translation, cultural adaptation and validation of the Italian version

BACKGROUNDː the aim of the study was to translate the Nonarthritic Hip Score (NAHS) questionnaire into the Italian language, to adapt it into the Italian culture and to validate it. METHODSː Translation and cultural adaptation were performed following international guidelines. To assess the reliability of the tool internal consistency and test-retest reliability were evaluated through Cronbach’s alpha and Intraclass Correlation Coefficient (ICC) respectively. Validity was evaluated by Pearson’s correlation coefficient between the NAHS, the Lequesne Index of Severity for Osteoarthritis of the Hip (LISOH) and the Western Ontario and McMaster Universities Arthritis Index (WOMAC), that were administered together. These three questionnaires were applied to a population of 64 individuals between 19 and 82 years old with generic hip injures or diseases. RESULTSː The items of the original version of NAHS are similar or equal to the items of the Italian version of NAHS. Cronbach’s α was 0.614 (Pain); 0.821 (Symptom); 0.877 (Function); 0.896 (Activity). ICC for total score was 0.905. The correlation with the WOMAC was 0.850 (p< 0.01) and with the LISOH was 0.738 (p<0.01). CONCLUSIONSː The NAHS showed positive results for reliability and validity so it was translated into Italian language and was cross-culturally adapted to Italian culture. This questionnaire is a good instrument in clinical practice and scientific research for the evaluation of young and active individuals affected by hip injures or diseases

Soil Biological Responses under Different Vegetation Types in Mediterranean Area

The knowledge of the effects of fire on soil properties is of particular concern in Mediterranean areas, where the effects of vegetation type are still scarce also. This research aimed: to assess the properties of burnt soils under different vegetation types; to highlight the soil abiotic properties driving the soil microbial biomass and activity under each vegetation type; to compare the biological response in unburnt and burnt soils under the same vegetation type, and between unburnt and burnt soils under different vegetation types. The soils were collected at a Mediterranean area where a large wildfire caused a 50% loss of the previous vegetation types (holm oak: HO, pine: P, black locust: BL, and herbs: H), and were characterized by abiotic (pH, water, and organic matter contents; N concentrations; and C/N ratios) and biotic (microbial and fungal biomasses, microbial respiration, soil metabolic quotient, and hydrolase and dehydrogenase activities) properties. The biological response was evaluated by the Integrative Biological Responses (IBR) index. Before the fire, organic matter and N contents were significantly higher in P than H soils. After the fire, significant increases of pH, organic matter, C/N ratio, microbial biomass and respiration, and hydrolase and dehydrogenase activities were observed in all the soils, especially under HO. In conclusion, the post-fire soil conditions were less favorable for microorganisms, as the IBR index decreased when compared to the pre-fire conditions

Effects of different vegetation types on burnt soil properties and microbial communities

The intensive wildfires recurring in the Mediterranean area modify soil physico-chemical properties, in turn inducing changes in soil microbial abundance and activity. Soils were sampled from burnt and adjacent unburnt sites within Vesuvius National Park 1 year after a large wildfire occurred in summer 2017. The aims of the present study were to evaluate the effects of fires on soil characteristics and to investigate whether different plant types contribute to mitigating or enhancing these effects. The results showed lower organic matter and water content and a higher C/N ratio in burnt than in unburnt soils. In particular, this trend was the same for all the plant types investigated, with the exception of soils covered by black locust tree and holm oak, which showed a higher C/N ratio in unburnt than in burnt soils. In soils covered by holm oaks, a shift in the bacterial and fungal fractions occurred between burnt and unburnt soils, whereas the amount of ammonia oxidisers was notably higher in burnt than in unburnt soils covered by black locusts; the highest N concentration was also measured in burnt soils covered by black locusts. The burnt soils showed a lower metabolic quotient and a higher rate of organic carbon mineralisation compared with unburnt soils, and this trend was particularly evident in soils under herbaceous plants. The findings suggest that soils covered by herbaceous species are more sensitive to fire effects and less able to restore their functionality compared with soils covered by trees

Varicose veins of the lower limbs and venous capacitance in postmenopausal women: Relationship with obesity

AbstractObjective: The purpose of this study was to examine the association between body mass index (BMI), venous capacitance, and clinical evidence of varicose veins after adjustment for sex hormones in postmenopausal women. Methods: This study group of the DIANA (DIet and ANdrogens) project (a randomized controlled trial on the effect of some dietary changes on sex hormone pattern in women with elevated androgenic hormone levels in Italy) was comprised of 104 healthy volunteer postmenopausal women, aged 48 to 65 years. The main outcome measures were physical examination to determine the presence and severity of varicose veins and plethysmographic measurement of lower limb venous capacitance and outflow. Results: Women in the upper quartile of BMI (>30 kg/m2) showed a positive association with clinical evidence of varicose veins (odds ration, 5.8; 95% CI, 1.2 to 28.2) after adjustment for age, estradiol, testosterone, and sex hormone binding globulin. No association was found between BMI and plethysmographic measurements of venous parameters. Conclusion: Obesity is associated with clinical evidence of varicose veins independently from the influence of sex hormones in postmenopausal women and is not associated with venous capacitance. Increased body weight increases the risk of varicose veins. (J Vasc Surg 2002;36:965-8.

Nanostructured lipid dispersions for topical administration of crocin, a potent antioxidant from saffron (Crocus sativus L.)

© 2016 Elsevier B.V.Crocin, a potent antioxidant obtained from saffron, shows anticancer activity in in vivo models. Unfortunately unfavorable physicochemical features compromise its use in topical therapy.The present study describes the preparation and characterization of nanostructured lipid dispersions as drug delivery systems for topical administration of crocin and the evaluation of antioxidant and antiproliferative effects of crocin once encapsulated into nanostructured lipid dispersions.Nanostructured lipid dispersions based on monoolein in mixture with sodium cholate and sodium caseinate have been characterized by cryo-TEM and PCS. Crocin permeation was evaluated in vitro by Franz cells, while the oxygen radical absorbance capacity assay was used to evaluate the antioxidant activity. Furthermore, the antiproliferative activity was tested in vitro by the MTT test using a human melanoma cell line.The emulsification of monoolein with sodium cholate and sodium caseinate led to dispersions of cubosomes, hexasomes, sponge systems and vesicles, depending on the employed emulsifiers. Permeation and shelf life studies demonstrated that nanostructured lipid dispersions enabled to control both rate of crocin diffusion through the skin and crocin degradation. The oxygen radical absorbance capacity assay pointed out an interesting and prolonged antioxidant activity of crocin while the MTT test showed an increase of crocin cytotoxic effect after incorporation in nanostructured lipid dispersions.This work has highlighted that nanostructured lipid dispersions can protect the labile molecule crocin from degradation, control its skin diffusion and prolong antioxidant activity, therefore suggesting the suitability of nanostructured lipid dispersions for crocin topical administration

Evaluation of a Novel Method Using Computed Tomography to Predict New Onset of Atrial Fibrillation or Embolic Events after Transcatheter Aortic Valve Implantation: the Role of Hounsfield Unit Density Ratio in the Left Atrial Appendage

Backgrounds: Evaluation of left atrial appendage (LAA) with angio-computed tomography (CCTA) in order to predict new onset of atrial fibrillation (AF) or embolic events is a new upcoming topic. No previous reported studies are available in patients undergoing transcatheter aortic valve implantation (TAVI). Methods: We analyzed pre-procedural CCTA scans of 325 patients who underwent TAVI performing a linear coefficient of attenuation analyses with Hounsfield units (HU) in LAA. HU in LAA distal and proximal was calculated, as well as the ratio. A sensibility and specificity analyses was conducted in order to identify the optimal cutoff to predict new onset AF or embolic events after TAVI. Results: Patients were divided into 4 groups according to the presence of AF. Baseline clinical and echocardiographic features were similar except for a significantly higher STS score and mitral regurgitation severity in PRE-TAVI AF group (p=0.003 and p=0.002 respectively). HU analyses showed a statistical difference in measure performed in LAA distal and in the HU LAA distal/Proximal ratio, with the lowest value in patients with pre-TAVI AF (p<0.001 and p<0.001 respectively). The ROC analyses found 0.84 as the cut-off for to predict the composite endpoint of new AF or embolic events, with sensitivity of 51% and specificity of 52% (p=0.008). Conclusion: In patients with aortic stenosis (AS), use of LAA assessment with CCTA to predict embolic events or new onset AF is no efficacy and cannot be substituted clinical indications for prevention and therapy of embolic events