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Marta BENINCASA

Personale tecnico amministrativo
Dipartimento di Scienze Biomediche, Metaboliche e Neuroscienze,sede Istituti Anatomici (area Policlinico)

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Pubblicazioni

2024 - Specific subcellular localization of phosphoinositide-specific phospholipase C enzymes in different human osteosarcoma cell lines [Articolo su rivista]
Corradini, M; Checchi, M; Benincasa, M; Ferretti, M; Cavani, F; Palumbo, C; LO VASCO, VINCENZA RITA
abstract

The role of signal transduction in cancer progression is well established and actively studied, including in osteosarcoma. The signal transduction pathways involved in the regulation of calcium metabolism are being intensively studied, with particular regard to phosphoinositide-specific phospholipase C (PLC) signaling. This family of enzymes helps to modulate calcium metabolism and is interconnected with additional signaling molecules belonging to different pathways. The expression and subcellular localization of PLCs have been shown to differ in normal cells compared to their neoplastic counterpart in different types of cancer. We now describe the localization of the PLC enzyme family in 4 human osteosarcoma cells different in origin and malignancy (MG63, U2OS, HOS and 143B cell lines). We identified cell line-specific differences and discussed possible meaning and implications.

2018 - Metformin induces apoptosis and alters cellular responses to oxidative stress in Ht29 colon cancer cells: Preliminary findings [Articolo su rivista]
Sena, P; Mancini, S; Benincasa, M; Mariani, Francesco; Palumbo, C; Roncucci, L
abstract

Accumulating evidence suggests that metformin, used as an antidiabetic drug, possesses anti-cancer properties. Metformin reduced the incidence and growth of experimental tumors in vivo. In a randomized clinical trial among nondiabetic patients, metformin treatment significantly decreased the number of aberrant crypt foci compared to the untreated group with a follow-up of 1 month. In our study, HT29 cells were treated with graded concentrations of metformin, 10 mM/25 mM/50 mM for 24/48 h. We performed immunofluorescence experiments by means of confocal microscopy and western blot analysis to evaluate a panel of factors involved in apoptotic/autophagic processes and oxidative stress response. Moreover, HT29 cells treated with metformin were analyzed by a flow cytometry assay to detect the cell apoptotic rate. The results demonstrate that metformin exerts growth inhibitory effects on cultured HT29 cells by increasing both apoptosis and autophagy; moreover, it affects the survival of cultured cells inhibiting the transcriptional activation of Nuclear factor E2-related factor 2 (NRF-2) and nuclear factor-kappa B (NF-κB). The effects of metformin on HT29 cells were dose- and time-dependent. These results are very intriguing since metformin is emerging as a multi-faceted drug: It has a good safety profile and is associated with low cost and might be a promising candidate for the prevention or the treatment of colorectal cancer.

2018 - Muscle-to-bone crosstalk: the Wnt/-catenin pathway is a candidate mechanism mediating the signalling between C2C12 muscle cells and 2T3 osteoblasts [Abstract in Rivista]
Magaro', MARIA SARA; Bertacchini, Jessika; Poti', Francesco; Checchi, Marta; Benincasa, Marta; Sena, Paola; Palumbo, Carla
abstract

The study aims to determine whether myokines can potentially regulate osteogenesis,

2017 - Expression and functional proteomic analyses of osteocytes from Xenopus laevis tested under mechanical stress conditions: preliminary observations on an appropriate new animal model [Articolo su rivista]
Bertacchini, Jessika; Benincasa, Marta; Checchi, Marta; Cavani, Francesco; Smargiassi, Alberto; Ferretti, Marzia; Palumbo, Carla
abstract

Hitherto, the role of the osteocyte as transducer of mechanical stimuli into biological signals is far from settled. In this study, we used an appropriate model represented by the cortex of Xenopus laevis long bone diaphysis lacking (unlike the mammalian one) of vascular structures and containing only osteocytes inside the bone matrix. These structural features allow any change of protein profile that might be observed upon different experimental conditions, such as bone adaptation to stress/mechanical loading, to be ascribed specifically to osteocytes. The study was conducted by combining ultrastructural observations and two-dimensional electrophoresis for proteomic analysis. The osteocyte population was extracted from long bones of lower limbs of amphibian skeletons after different protocols (free and forced swimming). The experiments were performed on 210 frogs subdivided into five trials, each including free swimming frogs (controls) and frogs submitted to forced swimming (stressed). The stressed groups were obliged to swim (on movable spheres covering the bottom of a pool on a vibrating plate) continuously for 8 h, and killed 24 h later along with the control groups. Long bones free of soft tissues (periosteum, endosteum and bone marrow), as well as muscles of posterior limbs, were processed and analyzed for proteins differentially expressed or phosphorylated between the two sample groups. The comparative analysis showed that protein phosphorylation profiles differ between control and stressed groups. In particular, we found in long bones of stressed samples that both Erk1/2 and Akt are hyperphosphorylated; moreover, the different phosphorylation of putative Akt substrates (recognized by specific Akt phosphosubstrates-antibody) in stressed vs. control samples clearly demonstrated that Akt signaling is boosted by forced swimming (leading to an increase of mechanical stress) of amphibian long bones. In parallel, we found in posterior limb muscles that the expression of heat shock protein HSP27 and HSP70 stress markers increased upon the forced swimming condition. Because the cortexes of frog long bones are characterized by the presence of only osteocytes, all our results establish the suitability of the X. laevis animal model to study the bone response to stress conditions mediated by this cell type and pave the way for further analysis of the signaling pathways involved in these signal transduction mechanisms.

2017 - Myeloperoxidase expression in human colonic mucosa is related to systemic oxidative balance in healthy subjects [Articolo su rivista]
Mancini, Stefano; Mariani, Francesco; Sena, Paola; Benincasa, Marta; Roncucci, Luca
abstract

Objectives: To improve understanding of the preclinical stage of colonic inflammation by exploring the existence of a link between early inflammatory changes in the colonic mucosa and the systemic redox balance. Methods: Clinical characteristics, a fasting blood draw, and mucosal biopsies from the right, left, and sigmoid-rectum colonic tracts collected from 28 healthy individuals (14/14 males/females) who underwent colonoscopy. Myeloperoxidase (MPO) positive cells infiltrating colonic mucosa specimens were assessed by immunohistochemistry, and patients divided into high or low MPO expressing cells/optical field groups (MPOhighor MPOlow, respectively).The systemic oxidative balance has been studied through derived-Reactive Oxygen Metabolites (d-ROMs), Biological Antioxidant Potential (BAP), and Lipoperoxide-cholesterol Oxidizing (LP-CHOLOX) tests on serum. Results: MPOhighpatients demonstrated an increased systemic oxidative stress compared to MPOlowindividuals (P = 0.035), especially when MPO is referred to the left-sided colonic mucosa (P = 0.007). MPOlowsubjects in the sigmoid-rectum showed a significant higher antioxidant capacity in the serum (P < 0.02). Sex-specific differences in MPO expression (male and female: 4.6 ± 3.2 and 2.6 ± 1.5 MPO-positive cells/optical field, respectively, P = 0.044), and a decreasing gradient in MPO expression moving from the cecum to the rectum (ascendant, descendant, and sigmoid-rectum: 3.7 ± 2.8, 3.1 ± 1.7, and 1.4 ± 0.5, respectively, P = 0.012) were also found and discussed. Discussion: The study is the first demonstrating a connection between systemic redox balance and MPO expression in the colonic mucosa, according to the colonic tract and patient gender. Further research evaluating the MPO expression in the human colon and its relationship with pathological conditions could benefit from these results.

2017 - Scleral ossicles as natural biomaterials on which vascular-like network is promoted from Mouse Aortic Endothelial cells (MAECs): preliminary results [Abstract in Rivista]
Checchi, Marta; Grisendi, Giulia; Bertacchini, Jessika; Magaro', MARIA SARA; Ferretti, Marzia; Benincasa, Marta; Sena, Paola; Cavani, Francesco; Palumbo, Carla
abstract

When a severe fracture is difficult to self-recovered, it is defined as “critical-size” bone defect. Till now, many efforts have been made by the tissue engineering (TE) to generate scaffolds suitable for recovering of this type of fracture, but the main obstacle remains the lack of an appropriate vascularization of the scaffolds. In the field of the regenerative medicine, the TE has developed many different biomaterials, with various features and peculiar functions, to be used in combination with cells and growth factors, in the generation of specialized constructs. Our proposal of natural scaffolds useful to obtain complex constructs concerns peculiar bony chips extracted from the eye bulb of adult chickens: the scleral ossicles (SOs). This proposed model is interesting because once SOs reach the definitive size in the adult animal, they are devoted only to mechanical stereotyped stress for their lifetime so that the activation of the bone remodelling should be avoided and, to do this, the osteocytes undergo massive apoptosis, making the ossicles like decellularized bones [1]. The novelty of our proposal is that the scaffolds do not require surface treatment (like further matrix deposition on the SO surface) since they are characterized, like all bones, by the well-known organic components such as type I-collagen fibres, proteoglycans and glycoproteins. The latter, for example, play the role of adhesion proteins and therefore can mediate the adhesion of the endothelial cells that should develop the vascular network. Our final goal is to obtain an in vitro 3D-vascularized natural constructs, from scaffolds easily available in nature to use in vivo for the healing of “critical-size” bone defeats. Previously [2] we identified the best preparation methods to obtain suitable SO surface for cell culture. Recently, we have performed a series of in vitro experiments to test the biocompatibility properties of the support; then, cell adhesion tests, viability and proliferation assay were carried out. Further, we tried to induce a vascular-like network organization of Mouse Aortic Endothelial Cells (MAECs) directly on the SOs surface, stimulating the cells with a known angiogenic factor, the Vascular Endothelial Growth Factor (VEGF), getting encouraging preliminary results.

2016 - PRELIMINARY OBSERVATIONS ON SCLERAL OSSICLES IN PERFORMING FUNCTIONALIZED 3D VASCULARIZED SCAFFOLDS FOR "CRITICAL_SIZE" BONE DEFECT HEALING [Abstract in Rivista]
Checchi, Marta; Smargiassi, Alberto; Ferretti, Marzia; Sena, Paola; Benincasa, Marta; Cavani, Francesco; Sola, Marco; Ranieri, Antonio; Stefania, Mitola; Palumbo, Carla
abstract

PRELIMINARY OBSERVATIONS ON SCLERAL OSSICLES IN PERFORMING FUNCTIONALIZED 3D VASCULARIZED SCAFFOLDS FOR "CRITICAL_SIZE" BONE DEFECT HEALING

2016 - Subclinical inflammation of colorectal mucosa is related to systemic oxidative balance in healthy adult subjects [Abstract in Rivista]
Mancini, Stefano; Mariani, Francesco; Sena, Paola; Benincasa, Marta; Roncucci, Luca
abstract

Oxidative balance is related to myeloperroxidase-positive cell count in normal colorectal mucosa

2015 - Autophagy is upregulated during colorectal carcinogenesis, and in DNA microsatellite stable carcinomas [Articolo su rivista]
Sena, Paola; Mariani, Francesco; Mancini, Stefano; Benincasa, Marta; Magnani, Giulia; Pedroni, Monica; Palumbo, Carla; Roncucci, Luca
abstract

Cancer cells are exposed to a wide range of stress sources, such as nutrient deprivation and hypoxia, as well as cytotoxic chemotherapy and radiotherapy. Certain forms of stress can also promote survival activating the metabolic autophagy pathway in cancer cells. Autophagy is dramatically increased in cancer cells. In these conditions, it is becoming evident that autophagy protects cells, by providing an alternative energy source and by eliminating dysfunctional organelles or proteins. Its role in tumorigenesis is more controversial and both the presence and the absence of autophagy have been implicated. Autophagy is known to be associated with the poor outcome of patients with various types of cancers, and its effectiveness as a prognostic marker in colorectal cancer was demonstrated by several studies. The inhibition of autophagy may be a potential therapeutic target in colorectal cancer. In vitro experiments have shown that the inhibition of autophagy increases 5-FU-induced apoptosis. There are two trials currently investigating the addition of chloroquine to 5-FU-based chemotherapy and bevacizumab. In the present study, we evaluated the expression of LC3B-II in samples of human colorectal microadenomas (i.e., dysplastic aberrant crypt foci) and carcinomas compared to normal mucosa. Furthermore, the expression pattern of LC3B-II was assessed in carcinomas classified as DNA microsatellite stable (MSS) and unstable (MSI). Thus, immunofluorescence techniques coupled with confocal microscopy and immunoblot experiments were performed. The results clearly showed a significant increase in expression of the autophagic key factor in microadenomas and carcinomas with respect to normal mucosa. In MSS carcinomas, the level of LC3B-II expression was higher than that in the MSI carcinomas.

2015 - Effects of PTH(1-34) during fracture healing after experimental bone drilling in rat femur: novel aspects [Abstract in Rivista]
Smargiassi, Alberto; Ferretti, Marzia; Cavani, Francesco; Sena, Paola; Benincasa, Marta; Palumbo, Carla
abstract

The study concerns the role of PTH(1-34) during bone lesion repair. 3-month-old male Sprague-Dawley rats, in which trans-cortical holes were drilled at femur middiaphysis, were divided in groups with/without Teriparatide administration (40g/ Kg/day), and sacrificed at different times (10, 28, 45 days). In 2002 (1) we demonstrated the occurrence of two successive bone forming processes during both skeletal organogenesis and bone repair, i.e. static (SO) and dynamic (DO) osteogenesis: the former (due to stationary osteoblasts, haphazardly grouped in cords) producing preliminary bad quality trabecular bone, the latter (due to typical polarized osteoblasts organized in ordered movable laminae) producing mechanically valid bone tissue. In brief, the primary function of SO is to provide a rigid scaffold, containing osteocytes (i.e. mechano-sensors), to DO-osteoblastic laminae; therefore, in DO mechanical factors can play a crucial role in transduction of mechanical stresses into biological signals. In the present work, histomorphometric analysis showed that, already after 10 days from drilling, notwithstanding the holes are temporarily filled by the same amount of newly-formed trabecular bone (produced by SO) independently from the treatment, the number of movable osteoblast laminae (typical of DO), covering the trabecular surface, is statistically higher in animals submitted to PTH(1-34) administration than in the control ones; this suggests that the mere effect of Teriparatide is to anticipate the occurrence of dynamic osteogenesis involved in the production of good quality bone more suitable to loading. These findings are also supported by the higher values of microhardness as well as the more ordered-fibered texture (observed by polarized light) in treated animals with respect to control ones that strongly indicates the qualitative (instead of quantitative) effect of PTH (1-34) in improving bone healing. The present investigation could be of crucial importance in further translational clinical research in humans to define the best therapeutic strategies in recovering skeletal lesions, particularly in terms of time of administration of PTH(1-34).

2014 - Effect of PTH (1-34) on trabecular bone of rat vertebral body in induced-biochemical osteoporosis by calcium- deprived diet [Abstract in Rivista]
Ferretti, Marzia; Cavani, Francesco; Smargiassi, Alberto; Sena, Paola; Benincasa, Marta; Palumbo, Carla
abstract

Rats fed calcium-deprived diet were used as experimental model for studying bone modelling alterations during biochemical osteoporosis and recovery of bone loss. Such model is suitable to evaluate the possible effects exerted by PTH(1-34) in preventing as well as in recovering metabolic osteoporosis. Three-month-old Sprague Dawley male rats were divided in different groups: some fed normal diet or calcium-deprived diet with/without 40µg/Kg/day PTH(1-34), provided by Eli Lilly-USA, for 4 weeks and some with restoration of normal diet with/without PTH (1-34) for further 4 weeks. To evaluate the occurrence of osteogenesis during the first 4 weeks of the experimental period, rats received three labels of bone deposition at 1st, 20th and 27th day (and then were sacrificed); during the successive 4 weeks (in which those rats previously fed with calcium-deprived diet had restoration of normal diet), animals received three labels of bone deposition at 1st, 7th and 14th day. Histomorphometrical analyses were performed on cortical and trabecular bone taken from the central level of the 5th lumbar vertebral body, transversely sectioned. The results showed that differences among the groups were observed mainly in trabecular bone with respect to cortical one, thus underlining the different role of the two types of bone architecture in mineral and skeletal homeostasis. Concerning trabecular bone, the observations showed that administration of PTH (1-34) during calcium-deprived diet and/or during the restoration of normal diet induces higher deposition of trabecular bone with respect to that recorded in rats that never received PTH(1-34), neither during calcium-deprived diet nor during restoration of normal diet. Since increments of trabecular bone are detectable only after the period of diet restoration (but not before), the authors suggest that a chronic administration of PTH (1-34) is necessary to achieve appreciable results on bone mass recovery.

2014 - Increased expression of autophagy-related proteins in human colorectal cancer development, and correlation with DNA Microsatellite Stable and Unstable [Abstract in Rivista]
Sena, Paola; Mancini, Stefano; Mariani, Francesco; Pedroni, Monica; Magnani, Giulia; Benincasa, Marta; Roncucci, Luca
abstract

Autophagy is upregulated during human colorectal carcinogenesis

2014 - Induction of altered cellular response to oxydative stress in HT29 colon cancer cells treated with metformin [Abstract in Rivista]
Sena, Paola; Mancini, Stefano; Mariani, Francesco; Pedroni, Monica; Benincasa, Marta; Roncucci, Luca
abstract

Metformin induces oxydative stress in HT29 colon cancer cells

2014 - Morphological and quantitative analysis of BCL6 expression in human colorectal carcinogenesis. [Articolo su rivista]
Sena, Paola; Mariani, Francesco; Benincasa, Marta; PONZ DE LEON, Maurizio; Di Gregorio, C; Mancini, Stefano; Cavani, Francesco; Smargiassi, Alberto; Palumbo, Carla; Roncucci, Luca
abstract

The aim of the present study was to determine whether BCL6 is expressed during malignant transformation of the large bowel and to assess whether, and to what extent, immunoreactivity is related to the different stages of neoplastic progression. Samples of normal colorectal mucosa (n=22), microadenomas (n=22) and colorectal cancer (n=22), were analyzed by immunohistochemistry, immunofluorescence coupled with confocal microscopy and western blotting. Our results clearly outlined the marked increase occurring in both intensity and density of BCL6 protein expression in the normal mucosa-microadenoma-carcinoma sequence. Immunohistochemistry and immunofluorescence analyses showed that BCL6 is expressed at low levels in normal mucosa and increases in microadenoma and in cancer with statistical significance. These results were confirmed by western blotting data. The increasing expression of BCL6 in human colorectal cancer development suggests the involvement of BCL6 in tumor progression, from the earliest stages of carcinogenesis with significant increase in cancer. The enhanced understanding of the biological role of BCL6, previously shown to exert a key role in lymphomagenesis, may lead to a re-evaluation of this protein and may highlight the importance of performing further studies in order to identify novel therapeutic targets for colorectal cancer.

2014 - Oral surgery biomaterials: analyses of Al2O3-treated titanium surfaces tested with fibroblast and osteocyte cell lines [Abstract in Rivista]
Smargiassi, Alberto; Ferretti, Marzia; Cavani, Francesco; Sena, Paola; Benincasa, Marta; Zaffe, Davide; Facciani, Valentino; Gabrel, Ivano; Palumbo, Carla
abstract

Two different cell lines - MLO-Y4 (murine osteocytes) and 293 (human fibroblasts) - cultured for 48 hours in standard media were used to analyse engineered bio-materials (i.e. Al2O3 shot-peened titanium surfaces). Distribution, density and expression of adhesion molecules (fibronectin and vitronectin) were evaluated under scanning electron microscope (SEM) and confocal microscope (CM) as previously described [1]. The engineered biomaterial surfaces showed under SEM irregular morphology displaying variously-shaped spicules, obtained by shooting different-in-size particles of Al2O3 against the scaffolds of biomaterial. DAPI and fluorochrome-conjugated antibodies were used to highlight nuclei, fibronectin and vitronectin, under CM; cell distribution was analysed after Gold-Palladium sputtering of samples by SEM. Both SEM and CM observations showed better outcome in terms of cell adhesion and distribution in treated titanium surfaces with respect to the untreated ones. The results obtained clearly showed that this kind of surface-treated titanium, used to manufacture devices for dental implantology: i) is very suitable for cell colonization, essential prerequisite for the best osseointegration, and ii) represents an excellent solution for the development of further engineered implants with the target to obtain recovery of dental function stable over time. Further studies on these Al2O3 shot-peened-titanium surfaces, both in vitro and in vivo, will be needed to obtain accurate definition of better biomaterial outcome, also after additional treatments. References [1] Palumbo et al. (2013) Immunocytochemical and structural comparative study of committed versus multipotent stem cells cultured with different biomaterials. Micron 47: 1–9.

2014 - Up-regulation of the chemo-attractive receptor ChemR23 and occurrence of apoptosis in human chondrocytes isolated from fractured calcaneal osteochondral fragments [Articolo su rivista]
Sena, Paola; Manfredini, Giuseppe; Benincasa, Marta; Mariani, Francesco; Smargiassi, Alberto; Catani, Fabio; Palumbo, Carla
abstract

To study the expression level of a panel of pro/anti-apoptotic factors and inflammation-related receptors in chondral fragments from patients undergoing surgical treatment for intra-articular calcaneal fractures, cartilage fragments were retrieved from calcaneal fractures of 20 patients subjected to surgical treatment. Primary cultures were performed using chondral fragments from fractured and control patients. Chondrocyte cultures from each patient of the fractured and control groups were subjected to immunofluorescence staining and quantitatively analyzed under confocal microscopy. Proteins extracted from the cultured chondrocytes taken from the fractured and control groups were processed for Western blot experiments and densitometric analysis. The percentage of apoptotic cells was determined using the cleaved PARP-1 antibody. The proportion of labelled cells was 35% for fractured specimens, compared with 7% for control samples. Quantification of caspase-3 active and Bcl-2 proteins in chondrocyte cultures showed a significant increase of the apoptotic process in fractured specimens compared with control ones. Fractured chondrocytes were positively stained for ChemR23 with statistically significant differences with respect to control samples. Densitometric evaluation of the immunoreactive bands confirmed these observations. Human articular chondrocytes obtained from patients with intra-articular calcaneal fractures express higher levels of pivotal pro-apoptotic factors, and of the chemoattractive receptor ChemR23, compared with control cultures. On the basis of these observations, the authors hypothesize that consistent prolonged chondrocyte death, associated with the persistence of high levels of proinflammatory factors, could enhance the deterioration of cartilage tissue with consequent development of post-traumatic arthritis following intra-articular bone fracture.

2013 - Chondrocyte expression of apoptotic and pro-inflammatory factors in the development of post- traumatic arthritis in humans [Abstract in Rivista]
Sena, Paola; Benincasa, Marta; Cavani, Francesco; Ferretti, Marzia; Smargiassi, Alberto; Manfredini, Giuseppe; Palumbo, Carla
abstract

The development of post-traumatic arthritis following intra-articular fracture remains an important unsolved clinical problem. The possibility that extensive chondrocyte apoptosis occurs following intra-articular fracture, thus contributing to the development of post-traumatic arthritis, has received increasing attention [1]. It has been demonstrated the existence of a direct correlation between the rate of apoptosis and the severity of osteoarthritis [2]. Pharmacologic inhibitors of enzymes involved in apoptosis have been explored as potential therapeutic agents [3]. In the present study we aimed to deepen the characterization of apoptotic mediators, expressed by chondrocytes, involved in human post-traumatic arthritis following intra-articular fracture and the possible implication of pro-inflammatory receptors in arthritis. The expression of a panel of pro/anti apoptotic factors (Caspase-3, PARP-1, BCL2) and inflammation-related receptors (ChemR23) were analysed in chondrocytes from patients undergoing surgery for intra-articular calcaneal fractures. The factors were investigated by immunofluorescence coupled with confocal analysis and western blotting, followed by densitometric evaluation of chondrocyte cultures harvested from patients with intra-articular fractures compared with control ones. The results clearly demonstrated that a statistically significant difference exists in the expression of pro/anti apoptotic factors and ChemR23 between fractured and control patients. In conclusion our data suggest that increased chondrocyte death, occurring after cartilage injury together with inflammatory process, could play a pivotal role in the onset of arthritic disease. References [1]. Hembree W.C. et al. (2007) Viability and apoptosis of human chondrocytes in osteochon-dral fragments following joint trauma. J Bone Joint Surg Br 89(10): 1388-95. [2] Kim H.A. et al. (2000) Apoptotic chondrocyte death in human osteoarthritis. J Rheumatol 27: 455–462. [3] D'Lima D. et al. (2006) Caspase inhibitors reduce severity of cartilage lesions in experi-mental osteoarthritis. Arthritis Rheum 54(6): 1814-1821.

2013 - Immunocytochemical and structural comparative study of committed versus multipotent stem cells cultured with different biomaterials. [Articolo su rivista]
Palumbo, Carla; Baldini, Andrea; Cavani, Francesco; Sena, Paola; Benincasa, Marta; Ferretti, Marzia; Zaffe, Davide
abstract

The aim of this work was the comparison of the behavior of committed (human osteoblast cells - hOB - from bone biopsies) versus multipotent (human dental pulp stem cells - hDPSC - from extracted teeth) cells, cultured on shot-peened titanium surfaces, since the kind of cell model considered has been shown to be relevant in techniques widely used in studies on composition/morphology of biomaterial surfaces. The titanium surface morphology, with different roughness, and the behavior of cells were analyzed by confocal microscope (CM), scanning electron microscope (SEM) and X-ray microanalysis. The best results, in terms of hOB adhesion/distribution, were highlighted by both CM and SEM in cultured plates having 20-mum-depth cavities. On the contrary, CM and SEM results highlighted the hDPSC growth regardless the different surface morphology, arranged in overlapped layers due to their high proliferation rate, showing their unfitness in biomaterial surface test. Nevertheless, hDPSC cultured inside 3D-matrices reproduced an osteocyte-like three-dimensional network, potentially useful in the repair of critical size bone defects. The behavior of the two cell models suggests a different use in biomaterial cell cultures: committed osteoblast cells could be appropriate in selecting the best surfaces to improve osseointegration, while multipotent cells could be suitable to obtain in vitro osteocyte-like network for regenerative medicine. The originality of the present work consists in studying for the first time two different cell models (committed versus multipotent) compared in parallel different biomaterial cultures, thus suggesting distinct targets for each cellular model. Copyright 2012 Elsevier Ltd. All rights reserved.

2013 - Induced Biochemical osteoporosis: Effects of 1-month calcium–deprived diet on rat bone remodelling with/without contemporary administration of PTH(1-34) [Abstract in Rivista]
Ferretti, Marzia; Cavani, Francesco; Sena, Paola; Benincasa, Marta; Smargiassi, Alberto; Palumbo, Carla
abstract

It is known that rats fed calcium-deprived diet develop osteoporosis due to en-hanced bone resorption secondary to parathyroid overactivity resulting from nutritional hypocalcemia. Therefore, rats provide a good experimental animal model for studying bone remodelling alterations during biochemical osteoporosis. This preliminary study is performed in 3 month-old Sprague Dawley male rats, divided into 4 groups (5 rats each): 1) base line, 2) normal diet for 4 weeks, 3) calcium-deprived diet for 4 weeks; 4) calcium-deprived diet for 4 weeks plus contemporary administration of PTH(1-34) 40µg/kg/day. Three labels of osteogenesis were performed at 1st , 20th and 27th day of experimental period in order to evaluate bone formation during animal treatment. His-tomorphometrical analyses were performed on cortical bone of femoral diaphyses, as well as on trabecular bone of distal femoral metaphyses, both transversely sectioned. The preliminary results showed that at femur mid-diaphyseal level the diet induced a reduction of cortical bone area (even if not significant) with enlargement of the medul-lary canal due to endosteal resorption, while periosteal neo-deposition is similar in all groups and particularly abundant in those periosteal regions mainly devoted in answering the mechanical demands. PTH(1-34) treatment seems to reduce endosteal resorption only in those surfaces where periosteal mechanical loading are less consistent. Conversely, PTH(1-34) treatment doesn't seem to affect osteoblast activity. Moreover, in distal femoral metaphyses, diet induced osteoclast activity, with a decrease in the amount of trabecular bone volume, confirming that this architecture is mainly devoted in answering the metabolic demands. The novelty of the proposed model Is the contemporary administration of PTH(1-34) together with calcium deprived diet to evaluate induced-biochemical osteoporosis. This model seems a good starting point for successive studies in order to study bone alterations during unbalanced calcium metabolism frequently occurring in aging and to define time and manner of bone mass recovery.

2012 - Matrix metalloproteinases 15 and 19 are stromal regulators of colorectal cancer development from the early stages [Articolo su rivista]
Sena, Paola; Mariani, Francesco; Marzona, Laura; Benincasa, Marta; PONZ DE LEON, Maurizio; Palumbo, Carla; Roncucci, Luca
abstract

Matrix metalloproteinases (MMPs) have been well characterized for their ability to degrade extracellular matrix proteins and, thus, they have been studied to elucidate their involvement in both tumor development and progression. In the present study, attention was focused on MMP-15 and MMP-19, two less known members of the MMP family. The expression profile of MMP-15 and -19 was assayed in samples of normal colorectal mucosa, microadenomas and cancer using confocal analysis, western blotting and quantitative reverse transcription polymerase chain reaction (qRT-PCR). Both qRT-PCR and western blotting showed that MMP-15 and MMP-19 appeared to be upregulated during colorectal tumorigenesis, with different expression patterns: MMP-15 expression level increases from normal mucosa to microadenomas, with a reduced level in cancer with respect to microadenomas; the semiquantitative immunofluorescence analysis showed a stromal localization of this protein in the early phases of neoplastic transformation. Increasing amount of MMP-19 mRNA and protein levels were observed in the progression of colonic lesions; MMP-19 staining increased in the normal mucosa-microadenoma-carcinoma sequence. Such different expression patterns, are probably due to the different roles played in colorectal tumorigenesis by these two molecules. Conflicting data on the role of these proteins in tumor progression have been reported, thus, an improved understandingof the biological roles of MMPs, in particular the lesser known members such as MMP-15 and 19, in colorectal cancer may lead to a re-evaluation of the use of MMP inhibitors and suggests the need of integrated translational studies on MMP expression patterns.

2012 - Osteocyte apoptosis and absence of bone remodeling in human auditory ossicles and scleral ossicles of lower vertebrates: a mere coincidence or linked processes? [Articolo su rivista]
Palumbo, Carla; Cavani, Francesco; Sena, Paola; Benincasa, Marta; Ferretti, Marzia
abstract

Considering the pivotal role as bone mechanosensors ascribed to osteocytes in bone adaptation to mechanical strains, the present study analyzed whether a correlation exists between osteocyte apoptosis and bone remodeling in peculiar bones, such as human auditory ossicles and scleral ossicles of lower vertebrates, which have been shown to undergo substantial osteocyte death and trivial or no bone turnover after cessation of growth. The investigation was performed with a morphological approach under LM (by means of an in situ end-labeling technique) and TEM. The results show that a large amount of osteocyte apoptosis takes place in both auditory and scleral ossicles after they reach their final size. Additionally, no morphological signs of bone remodeling were observed. These facts suggest that (1) bone remodeling is not necessarily triggered by osteocyte death, at least in these ossicles, and (2) bone remodeling does not need to mechanically adapt auditory and scleral ossicles since they appear to be continuously submitted to stereotyped stresses and strains; on the contrary, during the resorption phase, bone remodeling might severely impair the mechanical resistance of extremely small bony segments. Thus, osteocyte apoptosis could represent a programmed process devoted to make stable, when needed, bone structure and mechanical resistance.

2012 - Proposed roles of the immune response regulator-ThPOK in human colorectal cancer progression [Abstract in Rivista]
Sena, Paola; Mariani, Francesco; Roncucci, Luca; Benincasa, Marta; PONZ DE LEON, Maurizio; Palumbo, Carla
abstract

Solid tumours are commonly infiltrated by several immune cells [1-3]. In cancer, immune cells play conflicting roles with both the potentials to eliminate or to promote malignancy. In contrast to infiltration of cells responsible for chronic inflammation, the presence of high numbers of lymphocytes, especially T cells, has been reported to be important as indicator of good prognosis in many types of cancer [4-7]. The thorough knowledge of both manners and pathways with which tumors are able to evade immune-mediated attack, once established, is therefore of crucial importance. The strategies to escape anti-tumor immune responses include the limited priming or differentiation of antitumor T cells and the role of tumor microenvironment in order to prevent infiltration or activation of effector phase functions. We proposed to evaluate the role of Th inducing POZ-Kruppel Factor (ThPOK), a transcriptional regulator of T cell fate, in tumour-induced immune system plasticity during colorectal carcinogenesis. Data were collected on the amounts of CD4+, CD8+ and CD56+ as well as on ThPOK+ cells infiltrated in normal colorectal mucosa (NM), in dysplastic aberrant crypt foci (microadenomas, MA, the earliest detectable lesions in colorectal carcinogenesis) and in colorectal carcinomas (CRC); moreover, the colocalization of ThPOK with the above-mentioned markers of immune cells was evaluated using confocal microscopy. Interestingly, ThPOK showed a prominent increase since MA. A strong colocalization of ThPOK with CD4 both in NM and in MA was observed, weaker in carcinomas. Surprisingly, there was a peak in the colocalization levels of ThPOK with CD8 in MA, which was evident, although to a lesser extent, also in carcinomas. In conclusion, according to the data of the present study, ThPOK may be considered a central regulator of the earliest events in the immune system during colorectal cancer development. The novelty of the present study is the proposed role of ThPOK in influencing the immune response against cancer cells. References [1] Dunn et al. (2004) The immunobiology of cancer immunosurveillance and immunoediting. Immunity 21: 137-148. [2] Knaapen et al. (2006) Neutrophils and respiratory tract DNA damage and mutagenesis: a review. Muta-genesis 21: 225-236. [3] Coussens and Werb (2002) Inflammation and cancer. Nature 420: 860-867. [4] Watt and House (1978) Colonic carcinoma: a quantitative assessment of lymphocyte infiltration at the periphery of colonic tumors related to prognosis. Cancer 41: 279-282. [5] Galon et al. (2006) Type, density, and location of immune cells within human colorectal tumors predict clinical outcome. Science 313: 1960-1964. [6] Pagès et al. (2009) In situ cytotoxic and memory T cells predict outcome in patients with early-stage colorectal cancer. J Clin Oncol 27: 5944-5951. [7] Mlecnik et al. (2010) Biomolecular network reconstruction identifies T-cell homing factors associated with survival in colorectal. Gastroenterology 138: 1429-1434.

2012 - Role of osteocyte apoptosis in peculiar ossicles of the hearing sense organ: preliminary observations on hearing loss and osteoporosis [Abstract in Rivista]
Palumbo, Carla; Presutti, Livio; Genovese, Elisabetta; Cavani, Francesco; Sena, Paola; Benincasa, Marta; Ferretti, Marzia
abstract

Starting point of the present study is the osteocyte role in bone remodelling that allows bone adaptation to mechanical load [1-3]. Bone remodelling has been investigated in relation to the occurrence of apoptosis [4] to understand if and how the process of programmed cell death interferes with bone turnover. In 1998, in a study on human middle ear, Marotti et al. [5] demonstrated that: 1) over 40% of osteo-cytes are dead within the 2nd year of age (but the authors were not able to demonstrate if osteocyte death occurred by degeneration or apoptosis); 2) bone remodelling occurs only occasionally. Recently [6], we showed that: 1) osteocytes of human auditory ossicles die by apoptosis; 2) also osteocytes located inside scleral ossicles of lower vertebrate eye (reptiles and birds) phylogenetically so far from human auditory ossicles are widely affected by apoptosis (about 60%); 3) in scleral ossicles bone turnover never occur. It is to be noted that both auditory ossicles of human ear and scleral ossicles of vertebrate eye are peculiar bony segments continuously submitted to stereotyped stresses and strains, with specialized func-tions: the first are involved in sound wave transmission and the latter protect the eyeball against deformation during the movement and have a role in visual accomodation, providing attachment for the ciliary muscles. In both cases, bone remodelling might severely impair, by resorption, the mechanical resistance of these extremely small specialized bony segments. Thus, we suggested that in auditory and scleral ossicles, submitted to stereotyped loading for all life, bone mechanical adaptation is not needed and osteocyte programmed death could represent the mechanism to avoid bone remodelling and to make stable, when necessary, bone structure and mechanical resistance. More recently, to confirm this hypothesis, clinical data were collected from a cohort of patients aged 55-85 years affected by hearing loss. The main target of the present study is to exclude any correlation between hearing loss and osteoporosis. During osteoporosis, unbalanced bone turnover causes the bone depletion in skeletal segments; such condition, in the peculiar ossicles of human middle ear, should imply hearing impairment. Our preliminary observations indicate, instead, that osteoporotic patients do not show higher percentage of hearing loss with respect to non osteoporotic ones. This evidence is ascribable to osteocyte apoptosis of auditory ossicles that avoid bone remodelling, thus assuring the integrity of such bony segments also in osteoporotic conditions. References [1] Turner (1991) Omeostatic control of bone structure: an application of feed-bach theory. Bone 12: 203-217. [2] Turner and Forwood (1995) What role does the osteocyte network play in bone adaptation? Bone 16: 283-285. [3] Marotti (1996) The structure of bone tissue and the cellular control oftheir deposition. IJAE 101(4): 26-79. [4] Noble et al. (1997) Identification of apoptotic changes in osteocytes in normal and pathological human bone. Bone 20: 273-282. [5] Marotti et al. (1998) Morphometric investigation on osteocytes in human auditory ossicles. Ann Anat 180: 449-453. [6] Palumbo et al. (2012) Osteocyte apoptosis in human auditory ossicles and scleral ossicles of lower ver-tebrates: a mere coincidence or linked processes? Calcif. Tissue Int. 90: 211-218.

2012 - Structural and histomorphometric evaluations of ferutinin effects on the uterus of ovariectomized rats during osteoporosis treatment [Articolo su rivista]
Ferretti, Marzia; Bertoni, Laura; Cavani, Francesco; Benincasa, Marta; Sena, Paola; Carnevale, Gianluca; Zavatti, Manuela; Vittoria Di, Viesti; Zanoli, Paola; Palumbo, Carla
abstract

Aims: The effects of chronic administration of Ferutinin (phytoestrogen found in the plants of genus Ferula),compared with those elicited by estradiol benzoate, were evaluated, following ovariectomy, on the uterus ofovariectomized rats as regard weight, size, structure and histomorphometry.Main methods: The experimental study included 40 female Sprague–Dawley rats, assigned to two different protocols,i.e. preventive and recovering. In the preventive protocol, ferutinin (2 mg/kg/day)was orally administeredfor 30 days, starting from the day after ovariectomy; in the recovering protocol, ferutinin was administered, atthe same dosage, for 30 days starting fromthe 60th day after ovariectomy, when osteoporosiswas clearly established.Its effects were compared with those of estradiol benzoate (1.5 μg per rat twice a week, subcutaneouslyinjected) vs. vehicle-treated ovariectomized controls and vehicle-treated sham-operated controls. Uteri were removed,weighed and analysed under both the structural and histomorphometrical points of view.Key findings: Our data show that ferutinin acts, similarly to estradiol benzoate, on the uterus stimulating endometrialand myometrial hypertrophy; this notwithstanding, the phytoestrogen ferutinin, in contrast to estrogentreatment, appears to increase apoptosis in uterine luminal and glandular epithelia.Significance: Ferutinin, used in osteoporosis treatment primarily for bonemass recovering, seems in linewith aneventual protective function against uterine carcinoma, unlike estrogens so far employed in hormone replacementtherapy (HRT).

2011 - Effect of pulsed electromagnetic fields (PEMFs) on condrogenic phenotype maintenance of MSCs in presence of pro-inflammatory cytochines: preliminary results [Abstract in Rivista]
Palumbo, Carla; Ferretti, Marzia; Bertoni, Laura; Cavani, Francesco; Benincasa, Marta; Sena, Paola; Gian Luigi, Sacchetti; Stefania, Setti; Cadossi, Ruggero
abstract

The aim of the present study was to evaluate in vitro the effects of PEMFs on maintenance over time of chondrocyte phenotype of conditioned Mesenchimal Stem Cells (MSCs), in presence of pro-inflammatory cytokines (IL-ß1). MSCs, taken from bone marrow, were pellet-cultured in medium conditioning towards the chondrogenic lineage. Two targets were pursued: the first was to standardize the method to obtain chondrocyte pellets in terms of type/amount of withdrawal, time/degree of differentiation and amount of extracellular matrix production; the second was to extend over time chondrocyte differentiation, checking the phenotype maintenance, after adding pro-inflammatory IL-ß1 cytokine in culture medium with/without the application of PEMFs (device provided by IGEA-Carpi). The pellets obtained were coltured for different times (21, 28, 34 days), verifying the presence of type-II collagen (as index of chondrocyte differentiation) both by means of TEM analysis and immunoreaction. The best differentiation was obtained after 28 days of culture; in such pellets the studies were performed in triplicate for 15 days, identifying four experimental conditions: 1) without IL-b1 and PEMFs; 2) with IL-b1, without PEMFs; 3) without IL-b1 and with PEMFs; 4) with IL-b1 and PEMFs. The parameters of applied PEMFs were 1.7mT and 75Hz, and the time of application was 4 hours/day. Medium was changed every 3-4 days and stored for the evaluations of PGE2 (indicative of inflammation) and proteoglycans (indicative of chondrogenic differentiation). At the end of the experiment, each pellet was fixed with paraformaldehyde 4% and embedded in paraffin; sections (5 µm thick) were obtained and stained with Toluidin Blue in order to evaluate metachromasia. The results indicate that: 1) only the pellets treated with IL-b1 without PEMFs did not show metachromasia, indicanting a chondrocyte de-differentiation towards fibroblastic phenotype; 2) only in pellets treated with IL-b1 and with PEMF application, after about 12 days of treatment the amount of PGE2 in medium decreases (31%) while the proteoglycan production slightly increases (2%).In conclusion, if the results will be confirmed, pulsed electromagnetic fields could be proposed in preventing chondrocyte de-differentiation due to inflammation induced by IL-ß1; this with the final aim to integrate regenerative medicine techniques to apply in the healing of joint cartilage lesions with bio-physic energy devices, in order to obtain a stable-in-time recovery of physiologic function of articular surfaces that suffered a severe injury.

2011 - INTERACTION OF BIOPHYSIC STIMULI ON CONDROGENIC DIFFERENTIATION OF MSCs: PRELIMINARY RESULTS ON THE EVALUATION OF ANTI-INFLAMMATORY EFFECT OF ELECTROMAGNETIC FIELDS [Abstract in Rivista]
Palumbo, Carla; Ferretti, Marzia; Bertoni, Laura; Cavani, Francesco; Benincasa, Marta; Taronna, ANGELO PIO; Sena, Paola; Setti, S.; Cadossi, Ruggero
abstract

The aim of the present study is to investigate in vitro chondrocyte-like cells treated with electromagnetic fields to evaluate over time maintenance of chondrocyte phenotype, in presence of pro-inflammatory cytokines (IL-1ß). Mesenchimal Stem Cells taken from bone marrow were cultured (in pellet) in medium conditioning towards the chondrogenic lineage. The targets are firstly to standardize the method to obtain chondrocyte pellets in terms of a) type/amount of withdrawal, b) time/degree of differentiation, and c) amount of extracellular matrix production; secondly, to extend over time chondrocyte differentiation, checking the phenotype maintenance, after adding pro-inflammatory cytokines in culture medium with/without the application of electromagnetic fields (device provided by IGEA-Carpi). The pellets obtained were coltured for different times (21, 28, 34 days), verifying the presence of type 2 collagen (index of chondrocyte differentiation). The best differentiation was obtained after 28 days of culture. In such pellets, after inflammatory induction and application of electromagnetic field (1.7mT, 75Hz) for 15 days, the observations showed that after about 12 days of treatment the amount of PGE2 in medium decreases (31%) while the proteoglycan production slightly increases (2%). In conclusion, electromagnetic fields could be proposed (if the results will be confirmed) in preventing chondrocyte de-differentiation due to inflammation induced by IL-1ß, to integrate regenerative medicine techniques in the healing of cartilage lesions.

2011 - Reverse-phase protein microarrays (RPPA) as a diagnosticand therapeutic guide in multidrug resistant leukemia [Articolo su rivista]
Maraldi, Tullia; Bertacchini, Jessika; Benincasa, Marta; M., Guida; DE POL, Anto; L., Liotta LA; E., Petricoin; L., Cocco; Marmiroli, Sandra
abstract

Abstract. Reverse-phase microarray assays using phosphospecificantibodies (RPPA) can directly measure levels ofphosphorylated protein isoforms. In the current study, lysatesfrom parental and multidrug resistant (MDR) CEM leukemiacells were spotted onto reverse-phase protein microarraysand probed with a panel of phospho-antibodies to ERK, PCKand Akt pathways. In particular, the Akt pathway is consideredto play significant roles in leukemia and Akt inhibitor therapyhas been proposed as a potential tool in the treatment of thisdisease. The RPPA data prompted us to investigate deeperthis pathway. Here, we found that whereas total Akt1 proteinlevel is higher in parental CEM cells, the activated isoformcontent, p-Akt1, increases in doxorubicin-selected CEM cells(MDR-CEM). This was backed up by Western blot analysis,confirming that Akt1 activity/phosphorylation may be upregulatedin MDR-CEM cells. Further exploration of inhibitorytherapy in this system was evaluated. The TNF-relatedapoptosis-inducing ligand, TRAIL, has been shown toselectively kill tumor cells. Herein, we describe that in MDRCEMcells TRAIL responsiveness correlates with a reducedexpression of endogenous Akt1, suggesting that the MDRphenotype associated to P-gp sensitizes cells to TRAIL therapy.

2010 - Decreased osteocyte viability in multiple myeloma patients: osteolytic bone lesions, apoptosis and their potential role in bone remodeling alterations. [Abstract in Rivista]
Palumbo, Carla; Ferretti, Marzia; Benincasa, Marta; Lazzaretti, Mirca; M., Abeltino; M., Bolzoni; C., Mancini; E., Martella; P., Storti; N., Giuliani
abstract

Osteocytes seem to regulate bone remodelling by different manners including apoptosis. A reduction of osteocyte viability (OC-V) was shown in osteoporotic bone. Osteolysis/osteoporosis, induced by multiple myeloma (MM), are characterized by severely imbalanced uncoupled bone remodelling due to increased osteoclastogenesis and suppressed osteoblast differentiation occurring close to MM cell infiltration. The aim of this study is to investigate the eventual involvement of osteocytes in bone remodelling alterations occurring in MM patients. Iliac crest biopsies were taken from 34 patients with MM (52% of which displayed osteolytic bone lesions), 10 with monoclonal gammopathy of uncertain significance (MGUS) and 10 without haematological malignancies/osteoporosis/metabolic bone diseases. Viable osteocytes and degenerated or apoptotic osteocytes/empty lacunae were evaluated on 500 lacunae per histological section. Significant reductions of OC-V in MM patients were found compared to healthy controls, whereas not statistical significance in OC-V was observed between MM and MGUS. Death osteocytes/empty lacunae number was significantly increased in MM vs. controls but not as compared to MGUS. Concerning the skeletal involvement, in MM patients either OC-V percentage was significantly lower in osteolytic vs. non-osteolytic patients or the number of dead osteocytes/empty lacunae was higher in osteolytic vs. non-osteolytic patients. Monolayers were also performed of human preosteocytes incubated with/without conditioned media (CM) taken from human myeloma cell lines (HMCLs) or co-cultured with them, and TEM observations showed dead cells in those monolayers treated with HMCL-CM or co-cultured with HMCLs as compared to non treated cells. In CM of preosteocytes co-cultured with HMCLs significantly increased CD14+-derived osteoclastogenesis occurs, evaluated by TRAP staining and pit-forming assay. Our data demonstrate that MM bone is characterized by reduction of OC-V; the increase of osteocyte death (apoptosis/degeneration) in relation to the presence of bone lesions may represent a triggering event to osteoclast recruitment.

2008 - Influence of ferutinin on bone mass and its side effects in ovariectomized rats. [Abstract in Rivista]
Ferretti, Marzia; Palumbo, Carla; Bretoni, L.; Cavani, Francesco; Resca, E.; Benincasa, Marta; Carnevale, Gianluca; Zavatti, Manuela; Montanari, C.; Benelli, A.; Zanoli, P.; Marotti, Gastone
abstract

Ferutinin seems to display the same effects on bone mass recorded with estradiol, but with respect to estrogens it seems to extert a protection against uterine carcinoma.

2006 - Leptin effect on rat primary ossification centers during bone histogenesis. [Abstract in Rivista]
Palumbo, Carla; Ferretti, Marzia; Benincasa, Marta; Bertoni, Laura; Cavani, Francesco; Rivasi, M.; Benelli, A.
abstract

During the early phases of endochondral ossification, Leptin positive effects are shown in growith of rat ossification centers.

2002 - TUNEL REVEALS THE ONSET OF APOPTOSIS ON MESENCHYMAL CELLS IN STATIC AND DYNAMIC BONE FORMATION. [Abstract in Rivista]
Ferretti, Marzia; Palumbo, Carla; Benincasa, Marta; DE POL, Anto
abstract

Apoptosis is mostly associated with DBF with respect SBF during intramembranous ossification.

1999 - Static and dynamic bone formation and the mechanism of collagen fiber orientation. [Abstract in Rivista]
Marotti, Gastone; Ferretti, Marzia; Palumbo, Carla; Benincasa, Marta
abstract

Woven bone forms by FBS, whereas the deposition of a bone tissue with orderly arranged collagen fibers (parallel-fibered and lamellar bone) may only occur by DBF, i.e. by movable osteoblasts.

1996 - Zinc promoted addition of methyl 2,2-dihalocarboxylates to carbonyl compounds [Articolo su rivista]
Benincasa, Marta; Forti, Luca; Ghelfi, Franco; Libertini, Emanuela; Pagnoni, Ugo Maria
abstract

Methyl 2,2-dihalocarboxylates add easily to carbonyl compounds in fair to good yields through the intermediate formation of 2-haloester enolates; the reaction is promoted by zinc, following a ''Barbier'' type procedure.