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There is now ample evidence that blind individuals outperform sighted individuals in various tasks involving the non-visual senses. In line with these results, we recently showed that visual deprivation from birth leads to an increased sensitivity to pain. As many studies have shown that congenitally and late blind individuals show differences in their degree of compensatory plasticity, we here address the question whether late blind individuals also show hypersensitivity to nociceptive stimulation. We therefore compared pain thresholds and responses to supra-threshold nociceptive stimuli in congenitally blind, late blind and normally sighted volunteers. Participants also filled in questionnaires measuring attention and anxiety towards pain in everyday life. Results show that late blind participants have pain thresholds and ratings of supra-threshold heat nociceptive stimuli similar to the normally sighted, whereas congenitally blind participants are hypersensitive to nociceptive thermal stimuli. Furthermore, results of the pain questionnaires did not allow to discriminate late blind from normal sighted participants, whereas congenitally blind individuals had a different pattern of responses. Taken together, these results suggest that enhanced sensitivity to pain following visual deprivation is likely due to neuroplastic changes related to the early loss of vision.

The presence of brain atrophy and its progression in early Parkinson's disease (PD) are still a matter of debate, particularly in patients without cognitive impairment. The aim of this longitudinal study was to assess whether PD patients who remain cognitively intact develop progressive atrophic changes in the early stages of the disease. For this purpose, we employed high-resolution T1-weighted MR imaging to compare 22 drug-naïve de novo PD patients without cognitive impairment to 17 age-matched control subjects, both at baseline and at three-year follow-up. We used tensor-based morphometry to explore the presence of atrophic changes at baseline and to compute yearly atrophy rates, after which we performed voxel-wise group comparisons using threshold-free cluster enhancement. At baseline, we did not observe significant differences in regional atrophy in PD patients with respect to control subjects. In contrast, PD patients showed significantly higher yearly atrophy rates in the prefrontal cortex, anterior cingulum, caudate nucleus, and thalamus when compared to control subjects. Our results indicate that even cognitively preserved PD patients show progressive cortical and subcortical atrophic changes in regions related to cognitive functions and that these changes are already detectable in the early stages of the disease., (Copyright © 2014 Wiley Periodicals, Inc.)

In this study, we performed a complete histologic analysis of constructs based on large diameter ( >100 μm) poly-L-lactic acid (PLLA) microfibers obtained via dry-wet spinning and rat Mesenchymal Stromal Cells (rMSCs) differentiated towards the osteogenic lineage, using acrylic resin embedding. In many synthetic polymer-based microfiber meshes, ex post processability of fiber/cell constructs for histologic analysis may face deterring difficulties, leading to an incomplete investigation of the potential of these scaffolds. Indeed, while polymeric nanofiber (fiber diameter = tens of nanometers)/cell constructs can usually be embedded in common histologic media and easily sectioned, preserving the material structure and the antigenic reactivity, histologic analysis of large polymeric microfiber/cell constructs in the literature is really scant. This affects microfiber scaffolds based on FDA-approved and widely used polymers such as PLLA and its copolymers. Indeed, for such constructs, especially those with fiber diameter and fiber interspace much larger than cell size, standard histologic processing is usually inefficient due to inhomogeneous hardness and lack of cohesion between the synthetic and the biological phases under sectioning. In this study, the microfiber/MSC constructs were embedded in acrylic resin and the staining/reaction procedures were calibrated to demonstrate the possibility of successfully employing histologic methods in tissue engineering studies even in such difficult cases. We histologically investigated the main osteogenic markers and extracellular matrix molecules, such as alkaline phosphatase, osteopontin, osteocalcin, TGF-β1, Runx2, Collagen type I and the presence of amorphous, fibrillar and mineralized matrix. Biochemical tests were employed to confirm our findings. This protocol permitted efficient sectioning of the treated constructs and good penetration of the histologic reagents, thus allowing distribution and expression of almost all the tested molecules to be revealed. Our results demonstrated that it is possible to perform histologic analyses of large-diameter PLLA-based microfiber scaffold/MSC constructs that face the failure of standard histologic procedures.

Wandering represents one of many behavioural problems occurring in people with dementia. To consider the phenomenon of wandering behaviour in demented patients, we conducted searches using Medline and Google Scholar to find relevant articles, chapters, and books published since 1975. Search terms used included 'wandering', 'behavioural and psychological symptoms', 'dementia', 'nursing', and 'elopements'. Publications found through this indexed search were reviewed for further relevant references. The term 'wandering' covers different types of behaviour, including aimless movement without a discernible purpose. It is associated with a variety of negatives outcomes. The aetiology of wandering is poorly understood and it remains an unsolved riddle. Wandering is an acutely distressing problem worldwide, both for the patients and caregivers, and it is a major reason for nursing home admission. Evidence on the effectiveness of pharmacological and non-pharmacological interventions is limited. It is possible that management of coexistent psychopathology would help to ameliorate this problematic behavioural disorder., (© 2014 The Authors. Psychogeriatrics © 2014 Japanese Psychogeriatric Society.)

We analyzed the interactions between human primary cells from pancreatic ductal adenocarcinoma (PDAC) and polymeric scaffolds to develop 3D cancer models useful for mimicking the biology of this tumor. Three scaffold types based on two biocompatible polymeric formulations, such as poly(vinyl alcohol)/gelatin (PVA/G) mixture and poly(ethylene oxide terephthalate)/poly(butylene terephthalate) (PEOT/PBT) copolymer, were obtained via different techniques, namely, emulsion and freeze-drying, compression molding followed by salt leaching, and electrospinning. In this way, primary PDAC cells interfaced with different pore topographies, such as sponge-like pores of different shape and size or nanofiber interspaces. The aim of this study was to investigate the influence played by the scaffold architecture over cancerous cell growth and function. In all scaffolds, primary PDAC cells showed good viability and synthesized tumor-specific metalloproteinases (MMPs) such as MMP-2, and MMP-9. However, only sponge-like pores, obtained via emulsion-based and salt leaching-based techniques allowed for an organized cellular aggregation very similar to the native PDAC morphological structure. Differently, these cell clusters were not observed on PEOT/PBT electrospun scaffolds. MMP-2 and MMP-9, as active enzymes, resulted to be increased in PVA/G and PEOT/PBT sponges, respectively. These findings suggested that spongy scaffolds supported the generation of pancreatic tumor models with enhanced aggressiveness. In conclusion, primary PDAC cells showed diverse behaviors while interacting with different scaffold types that can be potentially exploited to create stage-specific pancreatic cancer models likely to provide new knowledge on the modulation and drug susceptibility of MMPs.

Alzheimer's disease and other dementia are associated with cognitive and functional impairment, as well as neuropsychiatric sequelae, including psychotic features. Research has largely concentrated on the study of cognitive decline, but the associated behavioral and neuropsychiatric symptoms are of equal importance in the clinical profile of the disease. Delusions are common, disabling and persistent in the course of dementia. The purpose of the present review was to examine the phenomenon of delusion in people with dementia. We searched the electronic databases for original research and review articles using the search terms "delusion, dementia, Alzheimer's disease, frontotemporal dementia, vascular dementia and Lewy body disease". Various types of explanations have been proposed regarding the etiology of delusional belief in dementia, and cerebral correlates are considered. Pharmacological and non-pharmacological treatments are analyzed., (© 2013 Japan Geriatrics Society.)

The traditional bone tissue-engineering approach exploits mesenchymal stem cells (MSCs) to be seeded once only on three-dimensional (3D) scaffolds, hence, differentiated for a certain period of time and resulting in a homogeneous osteoblast population at the endpoint. However, after achieving terminal osteodifferentiation, cell viability is usually markedly compromised. On the other hand, naturally occurring osteogenesis results from the coexistence of MSC progenies at distinct differentiative stages in the same microenvironment. This diversification also enables long-term viability of the mature tissue. We report an easy and tunable in vitro method to engineer simple osteogenic cell niches in a biomimetic fashion. The niches were grown via periodic reseeding of undifferentiated MSCs on MSC/scaffold constructs, the latter undergoing osteogenic commitment. Time-fractioning of the seeded cell number during differentiation time of the constructs allowed graded osteogenic cell populations to be grown together on the same scaffolds (i.e., not only terminally differentiated osteoblasts). In such cell-dynamic systems, the overall differentiative stage of the constructs could also be tuned by varying the cell density seeded at each inoculation. In this way, we generated two different biomimetic niche models able to host good reservoirs of preosteoblasts and other osteoprogenitors after 21 culture days. At that time, the niche type resulting in 40.8% of immature osteogenic progenies and only 59.2% of mature osteoblasts showed a calcium content comparable to the constructs obtained with the traditional culture method (i.e., 100.03 ± 29.30 vs. 78.51 ± 28.50 pg/cell, respectively; p=not significant), the latter colonized only by fully differentiated osteoblasts showing exhausted viability. This assembly method for tissue-engineered constructs enabled a set of important parameters, such as viability, colonization, and osteogenic yield of the MSCs to be balanced on 3D scaffolds, thus achieving biomimetic in vitro models with graded osteogenicity, which are more complex and reliable than those currently used by tissue engineers.

In this paper we investigated a novel and non-invasive approach for an endogenous osteoblast stimulation mediated by boron nitride nanotubes (BNNTs). Specifically, following the cellular uptake of the piezoelectric nanotubes, cultures of primary human osteoblasts (hOBs) were irradiated with low frequency ultrasound (US), as a simple method to apply a mechanical input to the cells loaded with BNNTs. This in vitro study was aimed at investigating the main interactions between hOBs and BNNTs and to study the effects of the 'BNNTs + US' stimulatory method on the osteoblastic function and maturation.A non-cytotoxic BNNT concentration to be used in vitro with hOB cultures was established. Moreover, investigation with transmission electron microscopy/electron energy loss spectroscopy (TEM/EELS) confirmed that BNNTs were internalized in membranal vesicles. The panel of investigated osteoblastic markers disclosed that BNNTs were capable of fostering the expression of late-stage bone proteins in vitro, without using any mineralizing culture supplements. In our samples, the maximal osteopontin expression, with the highest osteocalcin and Ca(2+) production, in the presence of mineral matrix with nodular morphology, was observed in the samples treated with BNNTs + US. In this group was also shown a significantly enhanced synthesis of TGF-β1, a molecule sensitive to electric stimulation in bone. Finally, gene deregulations of the analyzed osteoblastic genes leading to depletive cellular effects were not detected. Due to their piezoelectricity, BNNT-based therapies might disclose advancements in the treatment of bone diseases.

Vision is important for avoiding encounters with objects in the environment that may imperil physical integrity. We tested whether, in the absence of vision, a lower pain threshold would arise from an adaptive shift to other sensory channels. We therefore measured heat and cold pain thresholds and responses to suprathreshold heat stimuli in 2 groups of congenitally blind and matched normal-sighted participants. We also assessed detection thresholds for innocuous warmth and cold, and participants' attitude toward painful encounters in daily life. Our results show that, compared to sighted subjects, congenitally blind subjects have lower heat pain thresholds, rate suprathreshold heat pain stimuli as more painful, and have increased sensitivity for cold pain stimuli. Thresholds for nonpainful thermal stimulation did not differ between groups. The results of the pain questionnaires further indicated that blind subjects are more attentive to signals of external threats. These findings indicate that the absence of vision from birth induces a hypersensitivity to painful stimuli, lending new support to a model of sensory integration of vision and pain processing., (Copyright © 2013 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.)

Background: Tissue engineering appears to be an attractive alternative to the traditional approach in the treatment of fracture non-unions. Mesenchymal stromal cells (MSCs) are considered an appealing cell source for clinical intervention. However, ex vivo cell expansion and differentiation towards the osteogenic lineage, together with the design of a suitable scaffold have yet to be optimized. Major concerns exist about the safety of MSC-based therapies, including possible abnormal overgrowth and potential cancer evolution., Aims: We examined the long-term efficacy and safety of ex vivo expanded bone marrow MSCs, embedded in autologous fibrin clots, for the healing of atrophic pseudarthrosis of the upper limb. Our research work relied on three main issues: use of an entirely autologous context (cells, serum for ex vivo cell culture, scaffold components), reduced ex vivo cell expansion, and short-term MSC osteoinduction before implantation., Methods and Findings: Bone marrow MSCs isolated from 8 patients were expanded ex vivo until passage 1 and short-term osteo-differentiated in autologous-based culture conditions. Tissue-engineered constructs designed to embed MSCs in autologous fibrin clots were locally implanted with bone grafts, calibrating their number on the extension of bone damage. Radiographic healing was evaluated with short- and long-term follow-ups (range averages: 6.7 and 76.0 months, respectively). All patients recovered limb function, with no evidence of tissue overgrowth or tumor formation., Conclusions: Our study indicates that highly autologous treatment can be effective and safe in the long-term healing of bone non-unions. This tissue engineering approach resulted in successful clinical and functional outcomes for all patients.

Boron nitride nanotubes (BNNTs) represent an innovative and extremely intriguing class of nanomaterials. Thanks to their special chemical and physical characteristics, they have already found a large number of applications in the field of nanotechnology, and recent studies have shown their possible exploitation in the biomedical domain, both as nanocarriers and, more interestingly, as nanotransducers. In this review, the latest findings on the interactions between BNNTs and living systems are summarized, starting with the major issues of their stabilization in physiological media and their functionalization with bioactive molecules. Thereafter the biocompatibility data which have so far been made available are discussed, and the need for further extensive and standardized tests is highlighted. Finally, the appealing diagnostic and therapeutic opportunities offered by BNNT-based systems are described, envisioning the potential spill-over effects of such 'smart' and 'active' nanoparticles in nanomedicine., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Boron nitride nanotubes (BNNTs) represent an innovative and extremely intriguing class of nanomaterials, and preliminar but encouraging studies about their applications in biomedicine have emerged in the latest years. As a consequence, a systematic investigation of their biosafety has become of fundamental importance in the biomedical research. Extending our previous pilot in vivo study, here we present biocompatibility data of BNNTs injected in rabbits at a dose up to 10mg/kg. No significant adverse effects were found up to 7 days since their administration, and no impairments in blood, liver and kidney functionality were highlighted. Moreover, a terminal half-life circulation of about 90min was found. All the collected data are very promising, suggesting the optimal biocompatibility of BNNTs, and thus enabling their exploitation in nanomedicine as nanotransducers and nanocarriers., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Hypothesis: Precise knowledge of the expression and distribution of extracellular matrix (ECM) molecules and osteochondrogenic markers helps target the proper in vitro regeneration of novel ossicular chain (OC) replacements via tissue engineering (TE)., Background: We performed an extensive histologic analysis of human ear ossicles in healthy adults. A variety of OC prostheses are currently available, but extrusion of synthetic devices still represents an important clinical phenomenon. TE is a novel discipline combining stem cells, bioresorbable biomaterials, and stimulatory factors for the development of new living tissues in vitro, which might offer forefront opportunities to otologic surgery. However, to drive stem cell differentiation correctly, the final tissue target must be accurately known., Methods: Malleus, incus, and stapes were collected from cadaveric temporal bones. TE PORPs were obtained via osteodifferentiation of human mesenchymal stromal cells on polymeric scaffolds. Histochemical and immunohistochemical analyses were performed to detect ECM molecules and osteochondrogenic markers., Results: Malleus and incus showed the same histologic tissue type, with similar levels of expression and distributions for both ECM molecules and osteochondrogenic markers, whereas the stapes showed self-standing histologic patterns. In TE PORPs, mesenchymal ECM synthesis and early stage development of ossification sites could be observed, highlighting good cellular integration with the scaffold biomaterial., Conclusion: Detailed morphologic study of the ossicles provides data related to tissue dynamics involved in their development, defining features of tissue differentiation and maturation. Such findings underpin the future development of biomimetic ossicular replacement, data that can guide tissue-engineered ossiculoplasty.

While in the last years applications of carbon nanotubes in the field of biotechnology have been largely proposed, so far biomedical applications of boron nitride nanotubes (BNNTs) are still totally unexplored. BNNTs show very interesting physical properties that might be exploited in the nanomedicine field. To fill up the lack of biocompatibility studies on BNNTs, our group has recently begun a rational investigation on interactions between BNNTs and different cell lines. This chapter reports on preliminary cytocompatibility studies carried out on human neuroblastoma (SH-SY5Y) and on mouse myoblast (C2C12) cell lines as model of neural and skeletal muscle cells, respectively, highlighting the methods that allowed us to evaluate the main parameters of interests for cytocompatibility, such as cell viability, metabolism, apoptosis, and differentiation.

Objectives: The aim of this study was the fabrication of ossicular replacement prostheses (ORPs) from decellularized banked cortical bone via computer numerically controlled (CNC) ultraprecision micromilling, in order to obtain preformed clinical-grade tissue products, reproducing shape, size, and details perfectly comparable to those of synthetic devices., Methods: Banked femoral compact bone was used to fabricate partial and total ORPs via CNC micromilling according to Good Manufacturing Practices procedures. Drawings of ORPs with different shapes and sizes were uploaded to the computer interface, and different surface-finish parameters were tested. The obtained products underwent dimensional, weight, and surface characterizations. A histologic analysis was pursued to compare the bone matrix compactness of the produced ORPs to that of the ear ossicles., Results: Banked-bone ORPs were produced with high dimensional accuracy. Partial ORP weights averaged (+/- SD) 31.2 +/- 0.6 mg, and total ORP weights averaged 69.3 +/- 0.7 mg. The best-finish mode allowed microscale or nanoscale roughness free from machinery textures to be obtained. Finally, the histologic analysis confirmed that the extracellular matrix compactness of the produced ORPs was suitable for ossicular chain replacement., Conclusions: This study assesses the fabrication feasibility of novel banked-bone ORPs of extremely high dimensional accuracy. Such devices are aimed at combining the most favorable aspects of both synthetic (reproducibility, convenience, and biosafety) and biological replacements (total biocompatibility).

Recently, a differential recruitment of brain areas throughout the distributed neural system for face perception has been found in social phobic patients as compared to healthy control subjects. These functional abnormalities in social phobic patients extend beyond emotion-related brain areas, such as the amygdala, to include cortical networks that modulate attention and process other facial features, and they are also associated with an alteration of the task-related activation/deactivation trade-off. Functional connectivity is becoming a powerful tool to examine how components of large-scale distributed neural systems are coupled together while performing a specific function. This study was designed to determine whether functional connectivity networks among brain regions within the distributed system for face perception also would differ between social phobic patients and healthy controls. Data were obtained from eight social phobic patients and seven healthy controls by using functional magnetic resonance imaging. Our findings indicated that social phobic patients and healthy controls have different patterns of functional connectivity across brain regions within both the core and the extended systems for face perception and the default mode network. To our knowledge, this is the first study that shows that functional connectivity during brain response to socially relevant stimuli differs between social phobic patients and healthy controls. These results expand our previous findings and indicate that brain functional changes in social phobic patients are not restricted to a single specific brain structure, but rather involve a mis-communication among different sensory and emotional processing brain areas.

In this paper, we propose an absolutely innovative technique for the electrical stimulation of cells, based on piezoelectric nanoparticles. Ultrasounds are used to impart mechanical stress to boron nitride nanotubes incubated with neuronal-like PC12 cells. By virtue of their piezoelectric properties, these nanotubes can polarize and convey electrical stimuli to the cells. PC12 stimulated with the present method exhibit neurite sprout 30% greater than the control cultures after 9 days of treatment.

In the latest years, innovative nanomaterials have attracted a dramatic and exponentially increasing interest, in particular for their potential applications in the biomedical field. In this paper, we reported our findings on the cytocompatibility of barium titanate nanoparticles (BTNPs), an extremely interesting ceramic material. A rational and systematic study of BTNP cytocompatibility was performed, using a dispersion method based on a non-covalent binding to glycol-chitosan, which demonstrated the optimal cytocompatibility of this nanomaterial even at high concentration (100 μg/ml). Moreover, we showed that the efficiency of doxorubicin, a widely used chemotherapy drug, is highly enhanced following the complexation with BTNPs. Our results suggest that innovative ceramic nanomaterials such as BTNPs can be realistically exploited as alternative cellular nanovectors.

Thanks to a non-covalent wrapping with glycol-chitosan, highly biocompatible and highly concentrated dispersions of boron nitride nanotubes were obtained and tested on human neuroblastoma cells. A systematic investigation of the cytotoxicity of these nanovectors with several complementary qualitative and quantitative assays allowed a strong interference with the MTT metabolic assay to be highlighted, similar to a phenomenon already observed for carbon nanotubes, that would wrongly suggest toxicity of boron nitride nanotubes. These results confirm the high complexity of these new nanomaterials, and the needing of extensive investigations on their exciting potential applications in the biomedical field., (2010 Elsevier Inc. All rights reserved.)

This is a novel study aimed at exploring possible tissue engineering (TE) options for fabricating middle ear ossicle replacements. Alternatives to prosthetic replacements currently used in ossiculoplasty are desirable, considering that current devices are known to suffer from a persistent rejection phenomenon, known as extrusion. In this study a biocompatible and biodegradable polymer, poly(propylene fumarate)/poly(propylene fumarate)-diacrylate (PPF/PPF-DA), was chosen to assess the fabrication feasibility of highly porous devices shaped as partial ossicular replacement prostheses (PORPs). PORP-like scaffolds were produced, and their poral features (porosity and pore interconnectivity) were evaluated via micro-CT. In addition, their capability to support human mesenchymal stromal cell (hMSC) colonization and osteoblastic differentiation in vitro was investigated with both quantitative and qualitative analyses. This report summarizes and discusses all the fundamental issues associated with ossicle prosthetization as well as the challenging opportunities potentially offered to middle ear reconstruction by TE; moreover it demonstrates that PPF/PPF-DA PORP-like scaffolds can be appropriately fabricated to allow both the colonization of hMSCs and their osteoblastic maturation in vitro. Specifically, the expression patterns of the main osteogenic markers (alkaline phosphatase, calcium) and of various matrix biomolecules (glycoproteins, glycosaminoglycans, collagen I) were studied. These preliminarily obtained outcomes may launch a new trend in otology dedicated to TE ossicle development to improve on the performance of current prosthetic replacements., ((c) 2009 Wiley Periodicals, Inc.)

Alternatives for ossicular replacements were fabricated in order to overcome persisting rejections in middle ear prosthetization. Unlike the synthetic prostheses in fashion, we propose biological and biohybrid replacements containing extra cellular matrix (ECM) molecules to improve biointegration. In this study, ECM-containing devices shaped as Partial Ossicular Replacement Prostheses (PORPs) were fabricated reproducing the current synthetic models. Biological PORPs were obtained from human decellularized cortical bone allografts by computer numerically controlled ultraprecision micromilling. Moreover, porous PORP-like scaffolds were produced and cultured with osteoinduced human mesenchymal stromal cells to generate in vitro bone ECM within the scaffold porosity (biohybrid PORPs). The acoustic responses of such devices were investigated and compared to those of commercial prostheses. Results showed that biological PORPs transmit mechanical signals with appropriate frequencies, amplitudes, and with early extinction time. Although signal transmission in biohybrid PORPs showed insufficient amplitude, we believe that tissue engineered constructs represent the new challenge in ossiculoplasty.

Mesenchymal stem cells (MSCs) represent a promising source of progenitor cells having the potential to repair and to regenerate diseased or damaged skeletal tissues. Bone marrow (BM) has been the first source reported to contain MSCs. However, BM-derived cells are not always acceptable, due to the highly invasive drawing and the decline in MSC number and differentiative capability with increasing age. Human umbilical cord blood (UCB), obtainable by donation with a noninvasive method, has been introduced as an alternative source of MSCs. Here human UCB-derived MSCs isolation and morpho-functional characterization are reported. Human UCB-derived mononuclear cells, obtained by negative immunoselection, exhibited either an osteoclast-like or a mesenchymal-like phenotype. However, we were able to obtain homogeneous populations of MSCs that displayed a fibroblast-like morphology, expressed mesenchym-related antigens and showed differentiative capacities along osteoblastic and early chondroblastic lineages. Furthermore, this study is one among a few papers investigating human UCB-derived MSC growth and differentiation on three-dimensional scaffolds focusing on their potential applications in regenerative medicine and tissue engineering. UCB-derived MSCs were proved to grow on biodegradable microfiber meshes; additionally, they were able to differentiate toward mature osteoblasts when cultured inside human plasma clots, suggesting their potential application in orthopedic surgery.

Biodegradable synthetic polymers such as poly(lactic acid) (PLA) are widely used to prepare scaffolds for cell transplantation and tissue growth, using different techniques set up for the purpose. However the poor hydrophilicity of these polymers represents the main limitation to their use as scaffolds because it causes a low affinity for the cells. An effective way to solve this problem could be represented by the addition of biopolymers that are in general highly hydrophilic. The present work concerns porous biodegradable sponge-like systems based on poly(L-lactic acid) (PLLA) and gelatine. Morphology and porosity characteristics of the sponges were studied by scanning electron microscopy and mercury intrusion porosimetry respectively. Blood compatibility was investigated by bovine plasma fibrinogen (BPF) adsorption test and platelet adhesion test (PAT). The cell culture method was used in order to evaluate the ability of the matrices to work as scaffolds for tissue regeneration. The obtained results indicate that the sponges have interesting porous characteristics, good blood compatibility and above all good ability to support cell adhesion and growth. In fact viable and metabolically active animal cells were found inside the sponges after 8 weeks in culture. On this basis the systems produced seem to be good candidates as scaffolds for tissue regeneration.

In recent years MSCs have become a very attractive tool in tissue engineering and regenerative medicine because of their ability to be committed along several lineages through chemical or physical stimuli. Nevertheless their therapeutic potential and plasticity are not yet totally understood. This report describes the use of AFM together with conventional microscopies to obtain mechanical information on cell surfaces and deposited extra cellular matrix molecules, after inducing the differentiation of human MSCs towards three typical mesoderm phenotypes. The aim is to correlate morphological, functional, and mechanical aspects of human MSCs to obtain a deeper understanding of their great potential.

Biodegradable synthetic polymers such as poly(lactic acid) are widely used to prepare scaffolds for cell transplantation and tissue growth, using different techniques set up for the purpose. However the poor hydrophilicity of these polymers represents the main limitation to their use as scaffolds because it causes a low affinity for the cells. An effective way to solve this problem could be represented by the addition of biopolymers that are in general highly hydrophilic. The present work concerns porous biodegradable sponge-like systems based on poly(L-lactic acid) and gelatine. Morphology and porosity characteristics of the sponges were studied by scanning electron microscopy and mercury intrusion porosimetry respectively. Blood compatibility was investigated by bovine plasma fibrinogen adsorption test and platelet adhesion test. The cell culture method was used in order to evaluate the ability of the matrices to work as scaffolds for tissue regeneration. The obtained results indicate that the sponges have interesting porous characteristics, good blood compatibility and above all good ability to support cell adhesion and growth. In fact viable and metabolically active animal cells were found inside the sponges after 8 weeks in culture. On this basis the systems produced seem to be good candidates as scaffolds for tissue regeneration.

Poly(vinyl alcohol) hydrogels prepared by freeze-thawing procedure represent synthetic systems widely investigated as non-biodegradable scaffolds for tissue regeneration. In order to improve the biocompatibility properties of pure poly(vinyl alcohol) (PVA) hydrogels, blends of PVA with different biological macromolecules, such hyaluronic acid, dextran, and gelatin were prepared and used to produce "bioartificial hydrogels". The porosity characteristics of these hydrogels were investigated by scanning electron microscopy and mercury intrusion porosimetry. The morphology of bioartificial hydrogels was evaluated and compared with that of pure PVA hydrogels. In particular the effect exerted by each biological component on pore size and distribution was investigated. The obtained results indicate that when a natural macromolecule is added to PVA the internal structure of the material changes. A small amount of biopolymer induces the structural elements of PVA matrix to take on a well evident lamellar appearance and an apparent preferential orientation. Comparing the results of SEM and mercury intrusion porosimetry it was concluded that hydrogels containing 20% of biological component have the most regular structure and at the same time the lowest total porosity. On the contrary samples with the highest content of natural polymer (40%) show the less regular structure and the highest total porosity.

Two cDNA clones encoding catalase (Cat1 and Cat2) from peach [Prunus persica (L.) Batsch] were identified, that show homologies to other plant catalases. The nucleotide sequences of the two coding regions showed 88% identity to each other. The amino acid sequences predicted from the two full-length clones showed the highest homology to a catalase from cotton and Nicotiana plumbaginifolia L. and included C-terminal tri-peptides typical of those used to target proteins to peroxisomes. Southern hybridisation analysis suggested the existence of two catalase genes in peach. The expression of Cat1 and Cat2 was determined in seeds, vegetative tissue, leaves during the seasonal cycle and in leaves in response to light / dark treatments. Cat1 had high levels of expression only in leaf tissue and was responsive to light and seasonal changes. Cat2 had high levels of expression in in vitro shoots and was also responsive to seasonal changes, but not to light. In situ hybridisations to leaf tissue indicated that the expression of Cat1 was localised mainly in palisade cells, while Cat2 mRNA was present in the vascular tissue. The results of the expression analysis and in situ hybridisation suggest a role for Cat1 in photorespiration and for Cat2 in stress responses.

The authors describe a rare case of primary intestinal lymphangiectasis resolved with surgical treatment. Usually the natural course of the disease is relatively mild and medical nutritional treatment can be sufficient. In this case the lymphatic intestinal anomaly was generalized to the entire small intestine but a distal ileal segment was particularly involved. The surgical resection of this intestinal tract resolved the symptomatology.

In mice, the clenbuterol-induced decrease in spontaneous motor activity was antagonized by IPS-339 (beta 2 antagonist) but not by betaxolol (beta 1 antagonist), whereas the isoproterenol-induced decrease in spontaneous motor activity was completely antagonized by betaxolol and only partially by IPS-339. It can be concluded that the clenbuterol-induced decrease in spontaneous motor activity is of the beta 2-type, whereas that induced by isoproterenol is essentially of the beta 1 type. In addition, chronic treatment with clenbuterol induced a tachyphylaxis to the effect of clenbuterol but not of isoproterenol. After chronic administration of tricyclic antidepressants (imipramine and desipramine) the number of cortical beta 1 adrenergic receptors decreased without impairing the clenbuterol-induced decrease in spontaneous motor activity. We conclude that beta 2 adrenergic receptors mediate the clenbuterol-induced decrease in spontaneous motor activity and the tachyphylaxis to this effect after chronic treatment.

1. Mice were isolated for 7-9 days. An isolated mouse and a mouse reared in group show a difference in their behaviour when observed together under an inverted beaker. The isolated mouse makes one half escape attempts in regard to the grouped mouse. This is considered as a social behavioural deficit. 2. The effect of four tricyclic antidepressant drugs was tested on this social behavioural deficit. None of the following drugs acutely given: imipramine, desipramine, amitriptyline impaired the social behavioural deficit. Clomipramine reduced the deficit at the only dose of 2 mg/kg. The four antidepressants tended to increase the deficit at the high dose of 32 mg/kg but this may reflect a sedative effect. Chronic amitriptyline did not impair the social behavioural deficit. 3. It is concluded that acute and probably also chronic antidepressant treatments are without effect on the isolation induced social behavioural deficit test.

The beta-adrenergic agonist clenbuterol decreased interest in food in starved mice, 30 minutes after administration. This effect disappeared after repeated treatment with clenbuterol (0.25 mg/kg, twice daily). Three chronic injections were sufficient to prevent the effect of an acute dose of clenbuterol (0.125 mg/kg) up to 45 hours after treatment.

The beta-adrenergic stimulants isoprenaline, salbutamol and clenbuterol decreased motor activity, reduced the interest of fasting mice in food pellets ('Tantale' test), and antagonized high-dose apomorphine hypothermia. Clenbuterol was 16--60 times more potent than the other two agonists in all tests, apparently because of better crossing into the C.N.S. The beta-adrenergic blockers, d,l-propranolol and l-penbutolol, completely antagonized the effects of salbutamol and clenbuterol in tests of motor activity and apomorphine hypothermia, penbutolol being 30--60 times more active than propranolol, perhaps due to its greater lipid solubility. The Tantale test allows unambiguous differentiation between penbutolol and propranolol. While the first completely blocked the effects of clenbuterol and salbutamol, the second was effective only within a narrow dose range. Finally, the dose-effect relationships of the 3 agonists were parallel in the Tantale test, while they were divergent in the other two. This suggests that different classes of beta-adrenergic receptors may be involved in the various test.