Breast density in NF1 women: a retrospective study

Neurofibromatosis type 1 (NF1) is an autosomal dominant condition caused by neurofibromin haploinsufficiency due to pathogenic variants in the NF1 gene. Tumor predisposition has long been associated with NF1, and an increased breast cancer (BC) incidence and reduced survival have been reported in recent years for women with NF1. As breast density is another known independent risk factor for BC, this study aims to evaluate the variability of breast density in patients with NF1 compared to the general population. Mammograms from 98 NF1 women affected by NF1, and enrolled onto our monocentric BC screening program, were compared with those from 300 healthy subjects to verify differences in breast density. Mammograms were independently reviewed and scored by a radiologist and using a Computer-Aided Detection (CAD) software. The comparison of breast density between NF1 patients and controls was performed through Chi-squared test and with multivariable ordinal logistic models adjusted for age, body mass index (BMI), number of pregnancies, and menopausal status.breast density was influenced by BMI and menopausal status in both NF1 patients and healthy subjects. No difference in breast density was observed between NF1 patients and the healthy female population, even after considering the potential confounding factors.Although NF1 and a highly fibroglandular breast are known risk factors of BC, in this study, NF1 patients were shown to have comparable breast density to healthy subjects. The presence of pathogenic variants in the NF1 gene does not influence the breast density value.

Organotypic human lung bud microarrays identify BMP-dependent SARS-CoV-2 infection in lung cells

Although lung disease is the primary clinical outcome in COVID-19 patients, how SARS-CoV-2 induces lung pathology remains elusive. Here we describe a high-throughput platform to generate self-organizing and commensurate human lung buds derived from hESCs cultured on micropatterned substrates. Lung buds resemble human fetal lungs and display proximodistal patterning of alveolar and airway tissue directed by KGF. These lung buds are susceptible to infection by SARS-CoV-2 and endemic coronaviruses and can be used to track cell type-specific cytopathic effects in hundreds of lung buds in parallel. Transcriptomic comparisons of infected lung buds and postmortem tissue of COVID-19 patients identified an induction of BMP signaling pathway. BMP activity renders lung cells more susceptible to SARS-CoV-2 infection and its pharmacological inhibition impairs infection by this virus. These data highlight the rapid and scalable access to disease-relevant tissue using lung buds that recapitulate key features of human lung morphogenesis and viral infection biology.

Self-organized stem cell-derived human lung buds with proximo-distal patterning and novel targets of SARS-CoV-2

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of the global COVID-19 pandemic and the lack of therapeutics hinders pandemic control1-2. Although lung disease is the primary clinical outcome in COVID-19 patients1-3, how SARS-CoV-2 induces tissue pathology in the lung remains elusive. Here we describe a high-throughput platform to generate tens of thousands of self-organizing, nearly identical, and genetically matched human lung buds derived from human pluripotent stem cells (hPSCs) cultured on micropatterned substrates. Strikingly, in vitro-derived human lung buds resemble fetal human lung tissue and display in vivo-like proximo-distal coordination of alveolar and airway tissue differentiation whose 3D epithelial self-organization is directed by the levels of KGF. Single-cell transcriptomics unveiled the cellular identities of airway and alveolar tissue and the differentiation of WNThi cycling alveolar stem cells, a human-specific lung cell type4. These synthetic human lung buds are susceptible to infection by SARS-CoV-2 and endemic coronaviruses and can be used to track cell type-dependent susceptibilities to infection, intercellular transmission and cytopathology in airway and alveolar tissue in individual lung buds. Interestingly, we detected an increased susceptibility to infection in alveolar cells and identified cycling alveolar stem cells as targets of SARS-CoV-2. We used this platform to test neutralizing antibodies isolated from convalescent plasma that efficiently blocked SARS-CoV-2 infection and intercellular transmission. Our platform offers unlimited, rapid and scalable access to disease-relevant lung tissue that recapitulate key hallmarks of human lung development and can be used to track SARS-CoV-2 infection and identify candidate therapeutics for COVID-19.

Customised multiphasic nucleus/annulus scaffold for intervertebral disc repair/regeneration

Background: In the case of a degenerated intervertebral disc (IVD), even though spinal fusion has provided good short-term clinical results, an alteration of the spine stability has been demonstrated by long-term studies. In this context, different designs of IVD prostheses have been proposed as alternative to spinal fusion. However, over the past few years, much of the recent research has been devoted to IVD tissue engineering, even if several limitations related to the complex structure of IVD are still presented.Purpose/Aim: Accordingly, the aim of the current paper was to develop a strategy in designing customised multiphasic nucleus/annulus scaffolds for IVD tissue engineering, benefiting from the great potential of reverse engineering, additive manufacturing and gels technology.Materials and Methods: The device consisted of a customised additive-manufactured poly(ε-caprolactone) scaffold with tailored architectural features as annulus and a cell-laden collagen-low molecular weight hyaluronic acid-based material as nucleus with specific rheological and functional properties. To this aim, injectability and viscoelastic properties of the hydrogel were analyzed. Furthermore, a mechanical and biological characterization of cell-laden multiphasic nucleus/annulus scaffold was performed.Results and Conclusions: Analyses on the developed devices demonstrated appropriate viscoelastic and mechanical properties. As evidenced by rheological tests, the hydrogel showed a shear-thinning behaviour, supporting the possibility to inject the material. The mechanical characterization highlighted a compressive modulus which falls in the range of lumbar discs, with the typical initial J-shaped stress-strain curve of natural IVDs. Furthermore, preliminary biological tests showed that human mesenchymal stem cells were viable over the culture period.

3D Patterning of cells in Magnetic Scaffolds for Tissue Engineering

A three dimensional magnetic patterning of two cell types was realised in vitro inside an additive manufactured magnetic scaffold, as a conceptual precursor for the vascularised tissue. The realisation of separate arrangements of vascular and osteoprogenitor cells, labelled with biocompatible magnetic nanoparticles, was established on the opposite sides of the scaffold fibres under the effect of non-homogeneous magnetic gradients and loading magnetic configuration. The magnetisation of the scaffold amplified the guiding effects by an additional trapping of cells due to short range magnetic forces. The mathematical modelling confirmed the strong enhancement of the magnetic gradients and their particular geometrical distribution near the fibres, defining the preferential cell positioning on the micro-scale. The manipulation of cells inside suitably designed magnetic scaffolds represents a unique solution for the assembling of cellular constructs organised in biologically adequate arrangements.

Occupational Therapy's efficacy in children with Asperger's syndrome: a systematic review of randomized controlled trials

This systematic review of randomized controlled trials (RCTs) aims at evaluating the efficacy of Occupational therapy (OT) interventions in Asperger's syndrome (AS) pediatric patients. We conducted a systematic review according to PRISMA guidelines. The screening of the literature was carried out on PUBMED, SCOPUS, WEB OF SCIENCE and OT SEEKER databases, TO December 2018. We selected three RCTs having the common objective to evaluate whether children with AS can improve their social skills thanks to OT treatments. The interventions targeted by the three selected studies were: LEGO therapy, Social Use of Language Programme, Let's Face It! software and Parent Training combined with the administration of risperidone. All the studies showed that the intervention groups improved their overall social ability.This review shows that OT interventions can help concretely AS children in overcoming their social issues. Nevertheless, more RCTs are needed to better understand the OT's benefits and limitations in AS patients.

Preliminary focus on the mechanical and antibacterial activity of a PMMA-based bone cement loaded with gold nanoparticles

In total knee arthroplasty (TKA) and total hip replacement (THR) the restoration of the normal joint function represents a fundamental feature. A prosthetic joint must be able to provide motions and to transmit functional loads.

As reported in the literature, the stress distribution may be altered in bones after the implantation of a total joint prosthesis. Some scientific works have also correlated uncemented TKA to a progressive decrease of bone density below the tibial component. Antibiotic-loaded bone cements are commonly employed in conjunction with systemic antibiotics to treat infections. Furthermore, nanoparticles with antimicrobial activity have been widely analysed. Accordingly, the current research was focused on a preliminary analysis of the mechanical and antibacterial activity of a PMMA-based bone cement loaded with gold nanoparticles. The obtained results demonstrated that nanocomposite cements with a specific concentration of gold nanoparticles improved the punching performance and antibacterial activity. However, critical aspects were found in the optimization of the nanocomposite bone cement.

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Evaluation of the in vitro effects of bacterial adhesion and proliferation on modified bone cement samples.

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Assessment of anti-bacterial and anti-biofilm activities of the nanocomposite bone cement.

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Analysis of the effect of the inclusion of gold nanoparticles on mechanical performances of a PMMA-based bone cement.

Surface functionalization of acrylic based photocrosslinkable resin for 3D printing applications

The limited number of resins, available for stereolithography applications, is one of the key drivers in research applied to rapid prototyping. In this work an acrylic photocrosslinkable resin based on methyl methacrylate (MMA), butyl methacrylate (BMA) and poly(ethylene glycol) dimethacrylate (PEGDA) was developed with different composition and characterized in terms of mechanical, thermal and biological behaviour. Two different systems have been developed using different amount of reagent. The influence of every components have been evaluated on the final characteristic of the resin in order to optimize the final composition for applications in bone tissue engineering. The crosslinked materials showed good mechanical properties and thermal stabilities and moreover cytotoxicity test confirms good biocompatibility with no cytotoxic effect on cells metabolism. Moreover two different treatments have been proposed, using fetal bovine serum (FBS) and methanol (MeOH), in order to improve cell recognition of the surfaces. Samples threatened with MeOH allow cell adhesion and survival, promoting spreading, elongation and fusion of C2C12 muscle myoblast cells.

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Photocrosslinkable biocompatible resin for application in tissue engineering.

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Surface treatment to improve materials wettability.

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Myoblast spreading and elongation on photocrosslinked modified surfaces.

Bioactivation of calcium deficient hydroxyapatite with foamed gelatin gel. A new injectable self-setting bone analogue

An alternative approach to bone repair for less invasive surgical techniques, involves the development of biomaterials directly injectable into the injury sites and able to replicate a spatially organized platform with features of bone tissue. Here, the preparation and characterization of an innovative injectable bone analogue made of calcium deficient hydroxyapatite and foamed gelatin is presented. The biopolymer features and the cement self-setting reaction were investigated by rheological analysis. The porous architecture, the evolution of surface morphology and the grains dimension were analyzed with electron microscopy (SEM/ESEM/TEM). The physico-chemical properties were characterized by X-ray diffraction and FTIR analysis. Moreover, an injection test was carried out to prove the positive effect of gelatin on the flow ensuing that cement is fully injectable. The cement mechanical properties are adequate to function as temporary substrate for bone tissue regeneration. Furthermore, MG63 cells and bone marrow-derived human mesenchymal stem cells (hMSCs) were able to migrate and proliferate inside the pores, and hMSCs differentiated to the osteoblastic phenotype. The results are paving the way for an injectable bone substitute with properties that mimic natural bone tissue allowing the successful use as bone filler for craniofacial and orthopedic reconstructions in regenerative medicine.

The first systematic analysis of 3D rapid prototyped poly(ε-caprolactone) scaffolds manufactured through BioCell printing: the effect of pore size and geometry on compressive mechanical behaviour and in vitro hMSC viability

Novel additive manufacturing processes are increasingly recognized as ideal techniques to produce 3D biodegradable structures with optimal pore size and spatial distribution, providing an adequate mechanical support for tissue regeneration while shaping in-growing tissues. With regard to the mechanical and biological performances of 3D scaffolds, pore size and geometry play a crucial role. In this study, a novel integrated automated system for the production and in vitro culture of 3D constructs, known as BioCell Printing, was used only to manufacture poly(ε-caprolactone) scaffolds for tissue engineering; the influence of pore size and shape on their mechanical and biological performances was investigated. Imposing a single lay-down pattern of 0°/90° and varying the filament distance, it was possible to produce scaffolds with square interconnected pores with channel sizes falling in the range of 245-433 µm, porosity 49-57% and a constant road width. Three different lay-down patterns were also adopted (0°/90°, 0°/60/120° and 0°/45°/90°/135°), thus resulting in scaffolds with quadrangular, triangular and complex internal geometries, respectively. Mechanical compression tests revealed a decrease of scaffold stiffness with the increasing porosity and number of deposition angles (from 0°/90° to 0°/45°/90°/135°). Results from biological analysis, carried out using human mesenchymal stem cells, suggest a strong influence of pore size and geometry on cell viability. On the other hand, after 21 days of in vitro static culture, it was not possible to detect any significant variation in terms of cell morphology promoted by scaffold topology. As a first systematic analysis, the obtained results clearly demonstrate the potential of the BioCell Printing process to produce 3D scaffolds with reproducible well organized architectures and tailored mechanical properties.

Magnetic poly(ε-caprolactone)/iron-doped hydroxyapatite nanocomposite substrates for advanced bone tissue engineering

In biomedicine, magnetic nanoparticles provide some attractive possibilities because they possess peculiar physical properties that permit their use in a wide range of applications. The concept of magnetic guidance basically spans from drug delivery and hyperthermia treatment of tumours, to tissue engineering, such as magneto-mechanical stimulation/activation of cell constructs and mechanosensitive ion channels, magnetic cell-seeding procedures, and controlled cell proliferation and differentiation. Accordingly, the aim of this study was to develop fully biodegradable and magnetic nanocomposite substrates for bone tissue engineering by embedding iron-doped hydroxyapatite (FeHA) nanoparticles in a poly(ε-caprolactone) (PCL) matrix. X-ray diffraction analyses enabled the demonstration that the phase composition and crystallinity of the magnetic FeHA were not affected by the process used to develop the nanocomposite substrates. The mechanical characterization performed through small punch tests has evidenced that inclusion of 10 per cent by weight of FeHA would represent an effective reinforcement. The inclusion of nanoparticles also improves the hydrophilicity of the substrates as evidenced by the lower values of water contact angle in comparison with those of neat PCL. The results from magnetic measurements confirmed the superparamagnetic character of the nanocomposite substrates, indicated by a very low coercive field, a saturation magnetization strictly proportional to the FeHA content and a strong history dependence in temperature sweeps. Regarding the biological performances, confocal laser scanning microscopy and AlamarBlue assay have provided qualitative and quantitative information on human mesenchymal stem cell adhesion and viability/proliferation, respectively, whereas the obtained ALP/DNA values have shown the ability of the nanocomposite substrates to support osteogenic differentiation.

AvidinOX™ for tissue targeted delivery of biotinylated cells

AvidinOX™, a product containing aldehyde groups, generated by ligand-assisted sugar oxidation of avidin by sodium periodate, maintains the capacity to bind biotin with very high affinity and exhibits the property to chemically link cellular and tissue proteins through Schiff's base formation thus residing in tissues for weeks. In recent studies, we have shown that AvidinOX exhibits much higher persistency in the skeletal muscle than native avidin. The aim of the present study is to evaluate whether AvidinOX-biotin interaction might be exploited to target biotinylated cells to an AvidinOX pre-treated muscle. To accomplish this we performed the following experiments: 1) The proliferation and differentiation properties of biotinylated C2C12 myoblasts were tested in vitro upon linkage to AvidinOX; 2) Bone marrow-derived cells (BMDC) were isolated from GFP positive transgenic mice [strain C57 BL/6-tg (UBC-GFP)] and after biotinylation (bBMDC) were intravenously administered to naive and MAVA+ (Mouse anti Avidin Antibody) C57/B6 mice previously injected with AvidinOX in a tibial muscle (TM). Localization efficiency of GFP+ bBMDC was evaluated on serial sections of the AvidinOX- and vehicle-treated (contra lateral limb) TM, 5 days after transplantation. Results show that biotinylated C2C12 cells, once linked to AvidinOX, maintain their proliferation and differentiation capacity, in vitro. Intravenous injection of biotinylated GFP+ bone marrow-derived cells leads to their specific and efficient localization in the AvidinOX-pre-treated, but not contra lateral muscle of both naive and MAVA+ mice. The present data suggest a potential use of AvidinOX to improve tissue targeted delivery of biotinylated cells.

A FRET based melting curve analysis to detect nucleotide variations in HA receptor-binding site of H5N1 virus

Outbreaks of highly pathogenic H5N1 influenza A virus represent a major public health problem because of the possibility of direct transmission of these viruses from avian species to humans. For influenza H5N1 hemagglutinin, a switch from SA-a-2, 3-Gal to SA-a-2, 6-Gal receptor specificity is a critical step that could lead to inter-human transmission. The monitoring of the receptor-binding preference of H5N1 viruses represents an instrument to detect a potential pandemic virus. The aim of this study was to develop a method based on the fluorescence resonance energy transfer (FRET) technology and melting peaks analysis for rapid screening of pandemic H5N1 influenza A virus. Three selected probes corresponding to a 23bp nucleotide sequence of the avian receptor-binding site were used in a real-time RT-PCR to detect nucleotide variations. Five strains of avian influenza A viruses isolated from avian species and two synthesized HA gene were tested. The results showed that the melting peaks analysis is a reliable screening method for detecting the variability of the H5N1 receptor-binding site.

Fast curing of restorative materials through the soft light energy release

OBJECTIVE

The effect of a novel light curing process, namely soft light energy release (SLER), on shrinkage, mechanical strength and residual stress of four dental restorative materials (DEI experience, Gradia Direct, Enamel Plus HFO and Venus) was investigated.

METHODS

Composite specimens were fast cured through high level of power density and soft light energy release. Temperature, linear shrinkage and light power measurements were acquired in parallel in order to assess the effect of light modulation on temperature and shrinkage profiles during the light curing process and the following dark reaction phase. The small punch test and Raman spectroscopy were adopted to investigate the effect of SLER on mechanical strength and on internal stress, respectively.

RESULTS

The soft light energy release photo-polymerization allows to reduce of about 20% the shrinkage rate and to increase the strength of fast light cured specimens. In addition, a more relaxed and homogeneous internal stress distribution was observed.

SIGNIFICANCE

Properties of fast cured restorative materials can be improved by adopting the soft light energy release process.

IART (Intra-Operative Avidination for Radionuclide Therapy) for accelerated radiotherapy in breast cancer patients. Technical aspects and preliminary results of a phase II study with 90Y-labelled biotin

BACKGROUND

Breast conserving surgery (BCS) plus external beam radiotherapy (EBRT) is considered the standard treatment for early breast cancer. We have investigated the possibility of irradiating the residual gland, using an innovative nuclear medicine approach named IART(®) (Intra-operative Avidination for Radionuclide Therapy).

AIM

The objective of this study was to determine the optimal dose of avidin with a fixed activity (3.7 GBq) of (90)Y-biotin, in order to provide a boost of 20 Gy, followed by EBRT to the whole breast (WB) at the reduced dose of 40 Gy. Local and systemic toxicity, patient's quality of life, including the cosmetic results after the combined treatment with IART(®) and EBRT, were assessed.

METHODS

After tumour excision, the surgeon injected native avidin diluted in 30 ml of saline solution into and around the tumour bed (see video). Patients received one of three avidin dose levels: 50 mg (10 pts), 100 mg (15 pts) and 150 mg (10 pts). Between 12 to 24 h after surgery, 3.7 GBq (90)Y-biotin spiked with 185 MBq (111)In-biotin was administered intravenously (i.v.). Whole body scans and SPECT images were performed up to 30 h post-injection for dosimetric purposes. WB-EBRT was administered four weeks after the IART(®) boost. Local toxicity and quality of life were evaluated.

RESULTS

Thirty-five patients were evaluated. No side effects were observed after avidin administration and (90)Y-biotin infusion. An avidin dose level of 100 mg resulted the most appropriate in order to deliver the required radiation dose (19.5 ± 4.0 Gy) to the surgical bed. At the end of IART(®), no local toxicity occurred and the overall cosmetic result was good. The tolerance to the reduced EBRT was also good. The highest grade of transient local toxicity was G3, which occurred in 3/32 pts following the completion of WB-EBRT. The combination of IART(®)+EBRT was well accepted by the patients, without any changes to their quality of life.

CONCLUSIONS

These preliminary results support the hypothesis that IART(®) may represent a valid approach to accelerated WB irradiation after BCS. We hope that this nuclear medicine technique will contribute to a better management of breast cancer patients.

A novel bracket base design: biomechanical stability

The aim of this research was to investigate the retention of a bracket equipped with a novel base, the R-system. The design of the bracket base is characterized by concentric grooves. The behaviour of this bracket was compared with a bracket with a conventional mesh base from the same manufacturer. Thirty lower adult bovine incisors were selected and metallic brackets were bonded using the Concise adhesive system. Each bracket-adhesive-enamel interface was investigated according to torsion debonding. One-way analysis of variance was used for statistical evaluation. Finite element analysis was also undertaken. In order to assess if the technique was detrimental to the enamel, the mode of failure was determined using the Adhesive Remnant Index (ARI). The debonded surfaces were analysed using scanning electron microscopy (SEM) and electron dispersion spectrometry (EDS). The R-system provided a bond strength greater than that of the mesh-base bracket. EDS showed that the amount of calcium on the novel base was higher than that on the conventional base, which allowed transfer of torsional stress more uniformly to the substrate, resulting in higher bond values for the R-system. On the other hand, as debonding of the R-system occurred at the enamel-composite interface, lesions to the enamel substrate are possible.

The immunosuppressor st1959, a 3,5-diaryl-s-triazole derivative, inhibits T cell activation by reducing NFAT nuclear residency

3-(2-ethylphenyl)-5-(3-methoxyphenyl)-1H-1,2,4-triazole (ST1959) has shown therapeutic effects in several animal models of autoimmune diseases. In this study the effects of ST1959 were further investigated in a murine model of colitis. The evidence obtained indicates that the beneficial effects exerted by ST1959 rely upon a decreased local immunological response. The cellular effects of ST1959 were additionally investigated on human peripheral blood mononuclear cells and Jurkat T cells by measuring cytokine production, cell proliferation and activation of a set of transcription factors. ST1959 decreases human T cell proliferation and inhibits cytokine expression at the transcriptional level. Moreover, at doses inhibiting cytokine production, ST1959 blocks phorbol 12-myristate 13-acetate (PMA) and ionomycin-induced nuclear factor protein of activated T cell (NFAT1) activity, without impairing AP-1- and NF-kB-dependent transcription. Immunofluorescence data show that ST1959 inhibits the nuclear residency of NFAT1 in both Jurkat and human peripheral blood mononuclear cells activated with PMA/ionomycin. leptomycin B, an inhibitor of CRM1/exportin-1alpha-dependent nuclear export, reverted the inhibitory effect of ST1959 on NFAT1 nuclear localization. This indicates that ST1959 may increase the nuclear export of NFAT1, downregulating NFAT1 activity via a mechanism different from that of cyclosporin A, since it does not affect NFAT phosporylation/dephosphorylation steps. These findings provide new insights into the molecular mechanisms underlying the immunomodulatory activity of ST1959.

Biomechanical behavior of a novel composite intervertebral body fusion device

PURPOSE

Low back pain related to intervertebral disc (IVD) degeneration represents a socio-economic problem which affects quality of life. In order to solve this problem the current gold standard techniques such as spinal arthroplasty and arthrodesis (or fusion) are considered. As for spinal arthroplasty, over the past 40 yrs, IVD prostheses have been designed to maintain the correct IVD spacing and to allow for motion, while providing stability. However, there are many difficulties in incorporating important features such as viscoelastic and shock absorber behavior of natural IVDs in a prosthetic disc design. Moreover, in some cases, the use of IVD prostheses does not represent the ideal solution. Consequently, the aim of this study was to improve the design of alternative devices for spinal fusion, which overcome the problems related to metal ones currently available on the market, such as stress shielding, stress concentration effects and eventual bone corrosive or inflammatory reaction.

METHODS

Accordingly, a novel polyetherimide (PEI)-based cage reinforced with carbon fibers through filament winding and compression molding technologies was realized.

RESULTS

The characterization through a porcine model has produced very interesting results. The small values obtained from local compression tests have suggested that a reduction in mobility occurred, whereas distributed compression tests on IVDs prosthesized by employing the PEI-based cage reinforced with carbon fibers have highlighted a compressive stiffness of 100 MPa. This stiffness is lower than that of the IVD prosthesized through the titanium cage (146 MPa), and closer to the stiffness of natural porcine IVDs (90 MPa).

CONCLUSIONS

Through a suitable composite cage design it is possible to control stress-strain distributions and the mechanical signals to bone, thus avoiding the stress-shielding phenomena, but also corrosion and metal ions release which are typical of the metallic implants.

Structure of msj-1 gene in mice and humans: a possible role in the regulation of male reproduction

Msj-1 gene encodes a DnaJ protein highly expressed in spermatids and spermatozoa of both rodents and amphibians, possibly involved in vesicle fusion and protein quality control by means of interaction with heat shock proteins. We isolated and characterized the entire murine msj-1 gene and searched for putative msj-1-like genes into the human genome. Furthermore, ultrastructural localization of MSJ-1 was analyzed in mouse germ cells by immunogold electron microscopy. The analysis of murine msj-1 genomic sequence reveals that it is an intron less gene. Putative promoter region was predicted within the 600 bp upstream the transcription start site. In mouse, msj-1 maps on chromosome 1, into an intronic region of UDP glucuronosyl-transferase 1 family cluster. At ultrastructural level, MSJ-1 marks the developing acrosomic vesicle and the sperm centriolar region. A blast search against the human genome database revealed two closed regions (Ha and Hb) on human chromosome 2 having high nucleotide identity with murine msj-1 coding region. Similarly to mouse, in human both regions map into an intronic region of UDP glycosyl-transferase 1 family polypeptide A cluster (ugt1a@). A significant ORF encoding a putative DnaJ protein of 145 aa was predicted from Ha. Finally, expression analysis, conducted by RT-PCR in human sperm cells, demonstrated that Ha mRNA is effectively present in humans; by Western blot, a specific MSJ-1 band of approximately 30kDa was detected in human sperm. Taken together, these data suggest that msj-1 gene might be conserved among vertebrates and might exert fundamental functions in reproduction.

Basic structural parameters for the design of composite structures as ligament augmentation devices

Composite structures are designed to mimic the morphology and mechanical properties of natural ligaments. Filament winding technology has been implemented in order to obtain a composite material based on a polyurethane matrix (HydroThaneTM ), reinforced with degradable and non-degradable fibers. The mechanical properties of the matrix and fiber have been analysed to define the optimal type, volume ratio and winding angle of the reinforcement. The typical J-shaped stress-strain curve, displayed by natural tendons and ligaments, is reproduced. The mechanical behaviour of HydroThaneTM reinforced with poly(ethylene terephthalate) (PET) fibers were modified by varying the winding angle of the fibers. Fibers comprising poly(l-lactic acid) (PLLA), poly(glycolic acid) (PGA) and PET, individually and in combination, were considered as candidate materials for the reinforcement of a composite ligament augmentation device (LAD). Mechanical and degradation studies demonstrated that, by combining different types of fiber, at a fixed volume fraction and winding angle (20 degrees ), it is possible to optimize mechanical properties and degradation kinetics of the device.

An experimental and theoretical composite model of the human mandible

The purpose is to design and manufacture a composite mandible replicate suitable for testing the influence of prosthetic materials on the stress distribution of bone. Composite mandibles made of a poly(methylmethacrylate) core and a glass reinforced outer shell are manufactured and characterised through mechanical tests assisted by the finite element analysis. The mandible replicate has been conveniently equipped with strain gauges, moreover a video extensometer has also been used in order to measure the arch width change during loading. A close agreement is found between the experimental data and the theoretical predictions. By laterally loading the mandibles the maximum values of stress and strain take place in the premolar-incisal region. By varying technological parameters such as the fiber volume fraction and orientation, it is easy to replicate the behaviour of mandibles having different stiffnesses. The results obtained by laterally loading the composite mandibles through the condyles or through the gonion regions are consistent with literature data relative to the arch width decrease of natural jaws during opening and closing. This novel synthetic system coupled with the Finite Element model constitutes an experimental-theoretical model suitable to investigate the biomechanical effects of oral rehabilitations on mandibular bone.

Mandibular intrabony lesion as first sign of sarcoidosis: case report

A 33-year-old woman with intra-bony sarcoidosis of the mandible is reported. This presentation of sarcoidosis was the first sign of the disease in this patient, and was treated surgically because of an inaccurate biopsy report. Medical therapy was instituted once the diagnosis was made, and the disease was well controlled (including the mandibular localization) at 2 years follow-up.

Presence of TT virus DNA in bone marrow cells from hematologic patients

Recent observations suggest that TT virus (TTV), in addition to liver, may also infect bone marrow. In this study, bone marrow samples and sera from 33 patients with haematological disorders and sera from 16 healthy controls were investigated for TTV DNA presence. Altogether TTV DNA sequences were demonstrated in bone marrow cells of 84.84% of patients. Moreover TTV DNA was detected in sera from 72.72% of patients and from 93.75% of controls. N22 sequences amplified from bone marrow cells and serum of 3 patients were analysed, after cloning: all these isolates were of type 2c and 2 or 3 variants were present in each isolate. After single strand DNA degradation, replicative forms were detectable in BM cells. This finding, in addition to the detection of variants similar in the BM and in the serum of the same patient could suggest that BM is a site of TTV replication (or one of the sites) from which the virus is spread in blood.

Dynamic mechanical behavior of PMMA based bone cements in wet environment

The mechanical properties of three wet commercial bone cements, namely Braxel (from Bioland), Simplex-P (from Howmedica) and CMW1-G (from DePuy) are investigated by means of stress relaxation and dynamic mechanical analysis (DMA). The geometry of loading that was used is the three point bending method (ASTM D790); all the tests were performed in a water chamber by means of temperature sweeps between 17 and 57 degrees C and spanning four frequency decades. The results show that viscoelastic properties are strongly dependent on specimen conditioning (i.e. water uptake and heat treatment). The results also show that all the cements that were analyzed show mechanical properties which are intermediate between the ones of the cancellous bone and of the metals of which prostheses are normally made. As a consequence, the cement is able to reduce the stress concentrations due to the interfacing of materials which have very different stiffnesses. Moreover, the results of the DMA, particularly the ones concerning the damping factor (tan delta), indicate that at body temperature the bone cements tested show an increased capacity of dissipation, the higher is the loading frequency, thus displaying shock absorbing properties.

Polyomavirus BK infection in pediatric kidney-allograft recipients: a single-center analysis of incidence, risk factors, and novel therapeutic approaches

BACKGROUND

Although a growing body of literature regarding polyoma BK virus (BKV) infection and associated interstitial nephritis in kidney-allograft recipients is becoming available, the impact of BKV infection in the pediatric population has not been fully evaluated.

METHODS

In a retrospective analysis, we performed polymerase chain reaction (PCR) assays for BKV DNA in serum and urine samples from 100 pediatric kidney-allograft recipients referred to our institution in the last 5 years.

RESULTS

BKV viruria was observed in 26 of 100 patients, whereas BKV viremia was demonstrated in 5 patients. Serum creatinine was significantly higher in recipients with positive BK viremia compared with BKV DNA-negative patients (mean 2.66 vs. 1.14 mg/100 mL). Renal biopsy performed in 3 of 5 patients showed graft damage consistent with interstitial nephropathy. In the univariate analysis, negative antibody status of the recipient and the presence of mycophenolate mofetil in baseline immunosuppression were the two factors predictive of active BKV infection.

CONCLUSIONS

Our study shows that BKV-associated nephropathy is a relevant complication in the pediatric kidney transplantation setting also. Identification of patients at risk of developing virus-associated nephropathy, through prospective quantification of viral load, could improve clinical outcome by allowing the use of timely preemptive therapy guided by BKV DNA levels.

Novel antitenascin antibody with increased tumour localisation for Pretargeted Antibody-Guided RadioImmunoTherapy (PAGRIT)

The Pretargeted Antibody-Guided RadioImmunoTherapy (PAGRIT) method is based on intravenous, sequential administration of a biotinylated antibody, avidin/streptavidin and (90)Y-labelled biotin. The hybridoma clone producing the monoclonal antitenascin antibody BC4, previously used for clinical applications, was found not suitable for further development because of the production of an additional, nonfunctional light chain. In order to solve this problem, the new cST2146 hybridoma clone was generated. The monoclonal antibody ST2146, produced by this hybridoma, having the same specificity as BC4 but lacking the nonfunctional light chain, was characterised. ST2146 was found able to bind human tenascin at an epitope strictly related, if not identical, to the antigenic epitope of BC4. It showed, compared to BC4, higher affinity and immunoreactivity and similar selectivity by immunohistochemistry. Biodistribution studies of biotinylated ST2146 and three other monoclonal antitenascin antibodies showed for ST2146 the highest and more specific tumour localisation in HT29-grafted nude mice. On the overall, ST2146 appears to be a good alternative to BC4 for further clinical development of PAGRIT.

Spatial and structural dependence of mechanical properties of porcine intervertebral disc

Structure-function relationship of natural tissues is crucial to design a device mimicking the structures present in human body. For this purpose, to provide guidelines to design an intervertebral disc (IVD) substitute, in this study the influence of the spatial location and structural components on the mechanical properties of porcine IVD was investigated. Local compressive stiffness (LCS) was measured on the overall disc, also constrained between the two adjacent vertebrae: the dependence on the lumbar position was evaluated. The compliance values in the anterior position (A) were higher than both in the central posterior (CP) and in the lateral-posterior (RP, LP) locations. The values of Young's Modulus (74.67+/-6.03 MPa) and compression break load (1.36x10(4)+/-0.09x10(4)N) of the disc were also evaluated by distributed compression test. The NP rheological behavior was typical of weak-gels, with elastic modulus G' always higher than viscous modulus G" all over the frequency range investigated (G' and G" respectively equal to 320 and 85 Pa at 1 Hz) and with the moduli trends were almost parallel to each other.

Coracoclavicular joint: osteologic study of 1020 human clavicles

We examined 1020 dry clavicles from cadavers of Italian origin to determine the prevalence of the coracoclavicular joint (ccj), a diarthrotic synovial joint occasionally present between the conoid tubercle of the clavicle and the superior surface of the horizontal part of the coracoid process. Five hundred and nine clavicles from individuals of different ages were submitted to X-ray examination. Using radiography, we measured the entire length and the index of sinuosity of the anterior lateral curve, on which the distance between the conoid tubercle and the coracoid process depends. We also used radiography to record the differences in prevalence of arthritis in two neighbouring joints, the acromioclavicular and sternoclavicular joints. Of the 1020 clavicles, eight (0.8%) displayed the articular facet of the ccj. No statistical correlation was found between clavicular length and the index of sinuosity of the anterior lateral curve. The prevalence of arthritis in clavicles with ccj was higher than that revealed in clavicles without ccj. The prevalence of ccj in the studied clavicles is lower than that observed in Asian cohorts. Furthermore, ccj is not conditioned by either length or sinuosity of the anterior lateral curve of the clavicle. Finally, the assumption that ccj is a predisposing factor for degenerative changes of neighbouring joints is statistically justified.

Developmental genetics in primitive chordates

Recent advances in the study of the genetics and genomics of urochordates testify to a renewed interest in this chordate subphylum, believed to be the most primitive extant chordate relatives of the vertebrates. In addition to their primitive nature, many features of their reproduction and early development make the urochordates ideal model chordates for developmental genetics. Many urochordates spawn large numbers of transparent and externally developing embryos on a daily basis. Additionally, the embryos have a defined and well-characterized cell lineage until the end of gastrulation. Furthermore, the genomes of the urochordates have been estimated to be only 5-10% of the size of the vertebrates and to have fewer genes and less genetic redundancy than vertebrates. Genetic screens, which are powerful tools for investigating developmental mechanisms, have recently become feasible due to new culturing techniques in ascidians. Because hermaphrodite ascidians are able to self-fertilize, recessive mutations can be detected in a single generation. Several recent studies have demonstrated the feasibility of applying modern genetic techniques to the study of ascidian biology.

TT virus contaminates first-generation recombinant factor VIII concentrates

Recombinant factor VIII and factor IX concentrates, human-plasma-derived albumin, and samples from previously untreated patients with hemophilia were examined for the presence of TT virus (TTV) by using polymerase chain reaction testing. Blood samples from the patients were obtained prospectively before and every 3 to 6 months after therapy was begun. TTV was detected in 23.5% of the recombinant-product lots and 55.5% of the albumin lots tested. Only first-generation factor VIII recombinant concentrates stabilized with human albumin were positive for TTV, whereas all second-generation (human protein-free) concentrates were negative for the virus. In 59% of patients treated with either first- or second-generation recombinant factor concentrates, TTV infection developed at some point after the initial infusion. Infection with TTV in these patients before and after treatment did not appear to be clinically important. Thus, first-generation recombinant factor VIII concentrates may contain TTV and the source of the viral contamination may be human albumin.

Persistence of parvovirus B19 DNA in synovium of patients with haemophilic arthritis

A progressive arthropathy develops commonly in haemophiliacs and its pathogenesis is not fully understood. Human parvovirus B19 has been associated with several diseases including acute and chronic arthropathy and some studies suggest its implication in chronic inflammatory diseases of the joints such as rheumatoid arthritis. In haemophiliacs parvovirus B19 infection occurs very frequently because of its transmission with plasma derivatives. In order to assess a role of B19 virus in haemophilic arthritis, synovial tissue samples from patients with haemophilia with arthritis and from patients, nonhaemophiliacs, with arthrosis or with joint trauma were examined for B19 DNA by nested PCR. In addition, the prevalence of antibody to parvovirus B19 NS1 protein as a possible serological marker of persistent B19 infection was tested and the association of the outcome of parvovirus infection with genetic diversity of B19 P6 promoter sequences was investigated. B19 DNA was detected in the synovial tissue of 31% of haemophiliacs with progressive arthropathy and of 5% of control patients. Fourteen out of 17 patients (82%) with haemophilic arthritis and with B19 DNA in their synovial membranes had IgG antibodies against the nonstructural protein NS1 of parvovirus B19. On the other hand, 19% of patients with haemophilia with B19 PCR negative synovial tissue and 21% of controls showed anti-NS1 antibodies. The P6 promoter presented specific sites of point mutations shared frequently by isolates from patients with haemophilia and arthritis. These results indicate that B19 DNA can persist in the synovial membranes of patients with haemophilic arthritis significantly more frequently in comparison to control individuals with arthrosis or joint trauma and show a correlation between anti- NS1 antibody presence and B19 DNA persistence in the synovial tissue.

Mechanical strength of tooth fragment reattachment

The aim of this study was static and fatigue test investigation of the strength of a tooth fragment reattached with adhesives to the tooth body. Central bovine incisor teeth were used, and standardized fragments were obtained by cutting the incisal edge of the selected teeth. All the fragments were reattached using a multistep dentine adhesive system, and the specimens were randomly divided into two groups (A and B). Group B specimens underwent a further dental treatment: a circumferential double chamfer prepared around the external cut interface was filled with light cured composite restorative resin. Static and fatigue bending tests were performed and linear elastic equations were used to analyze and compare the strength of the treated teeth. The results indicated that the static and fatigue bending properties were improved by using reinforcement with composite restorative resin.

Human herpesvirus 8 DNA sequences are present in bone marrow from HIV-negative patients with lymphoproliferative disorders and from healthy donors

Bone marrow (BM) from patients affected by multiple myeloma (MM), exhibiting monoclonal gammopathy of undetermined significance (MGUS) or with non-Hodgkin lymphoma (NHL) as well as from healthy donors were investigated for the presence of human herpesvirus-8 (HHV-8) DNA sequences. ORF 26 sequences were detected in 36--56% of the patients and in 29% of the controls. In a few cases, two other HHV-8 DNA sequences were also detected. These observations indicate that the presence of the HHV-8 genome in BM is relatively common in different groups of patients as well as in healthy individuals and do not support an alleged role for HHV-8 in MM.

Bone fracture analysis on the short rod chevron-notch specimens using the X-ray computer micro-tomography

Mechanical fatigue of bone leads to micro-cracking which is associated with remodeling, establishing a balance in the microcrack population of the living tissue, thus, in the steady-state, the microstructure of bone provides sites of discontinuity acting as stress raisers. Hence fracture toughness plays a decisive role in bone functionality by determining the level to which the material can be stressed in the presence of cracks, or, equivalently, the magnitude of cracking which can be tolerated at a given stress level. Cortical bone, which behaves as a quasi-brittle solid when fractured, was tested as short-rod chevron-notched tension specimens (CNT). The main features of the CNT specimen are its geometry and the V shaped notch. The notch leads to steady-state crack propagation whilst the requested geometry allows a diameter 40% smaller than the thickness of a standard compact tension specimens (CT). These features are essential to distinguish the inhomogeneties in the fracture properties of materials like bone. Bone structure and crack propagation of the CNT specimens were analyzed using X-ray computed micro-tomography (XMT), which is a non-invasive imaging technique. The unique feature of the micro-CT is the high resolution three-dimensional image which consists of multi-sliced tomographs taken in a fine pitch along the rotational axis. Fracture toughness (K(IC)) computed according to the peak load was 4.8 MNm(-3/2) while that derived from experimental calibration tests using XMT was 4.9 MNm(-3/2).

The fusion protein MEN 11303 (granulocyte-macrophage colony stimulating factor/erythropoietin) acts as a potent inducer of erythropoiesis

OBJECTIVE

A fusion protein made of human granulocyte-macrophage colony-stimulating factor (GM-CSF) and erythropoietin (EPO), referred to as MEN 11303, has been tested for biologic activity using mobilized CD34(+) cells.

METHODS AND RESULTS

MEN 11303 and a combination of GM-CSF/EPO produced the same amount of colony-forming unit granulocyte-macrophage (CFU-GM), of burst-forming unit erythroid (BFU-E), and of multipotent CFU-mixed. After 15 days, liquid cultures of CD34(+) cells exposed to MEN 11303 yielded a total cell number larger than that obtained with an equimolar mixture of GM-CSF and EPO, with a clear prevalence of cells exhibiting an erythroid phenotype. A colony-forming cell assay established from CD34(+) cells precultured with MEN 11303 for 7 days yielded a greater amount of BFU-E than GM-CSF/EPO combination. Exposing CD34(+) cells to MEN 11303 for 7 days in liquid culture resulted in higher recoveries of cells expressing a comparatively less differentiated hematopoietic phenotype and of long-term culture initiating cells. A cell-based binding-competition assay using the human EPO-receptor (EPO-R) transfected murine Ba/F3EPOR cell line showed that MEN 11303 bound to EPO-R with a sixfold lower affinity but induced a more sustained receptor phosphorylation. MEN 11303 supported the growth of Ba/F3EPOR cells more efficiently than EPO and remained detectable in the spent culture medium for a longer time.

CONCLUSIONS

MEN 11303 and the combination of GM-CSF/EPO are equally potent in recruiting hematopoietic progenitors into cycle, but the fusion protein is superior in promoting the expansion of committed erythroid percursors. Primitive hematopoiesis is less affected by MEN110303 than GM-CSF/EPO combination. Part of these effects may reflect the peculiar interaction of the EPO moiety of MEN 11303 with the EPO-R.

Carbon fiber post adhesion to resin luting cement in the restoration of endodontically treated teeth

Carbon fiber posts (CFP) are widely used in the restoration of endodontically treated teeth to enhance the mechanical behavior in spite of metallic posts and to prevent vertical fractures of the tooth under chewing loads. The post is cemented inside the canal lumen using polymer resins with Young's modulus lower than dentine. In this conditions the stress concentration is located at the post-cement interface and in the cement bulk itself, preserving radicular dentine from dangerous stress accumulation. The mechanical resistance of CFP posts cemented in human dentine was evaluated by the means of mechanical pull-out tests assisted by the finite element analysis. The average bond strength and the critical stress values of the CHP-cement interface were 25 MPa and 50 MPa respectively.