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Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Cloning of the Minimal Functional Domain of Human Lim Mineralization Protein-3 Able To Induce Bone Mineralization: In Vitro and In Vivo Study
No full textHuman LIM mineralization protein (LMP)-3 is one of the three
splice variants of LMP recently identified. LMPs are involved in
the osteoblast differentiation program and structurally characterized
by the two conserved LIM and PDZ domains. Human LMP-1
(hLMP-1) shows one N-terminal PDZ domain and three C-term
LIM domains connected by a non-conserved Unique region, deleted
in the hLMP-2. hLMP-3 misses almost completely the LIM domains
along with part of the unique region, due to a frame shift mutation.
The three isoforms are expressed almost ubiquitously but show
quantitative differences, hLMP-3 being the less expressed in all the
analyzed tissues. Both hLMP-1 and hLMP-3 has been demonstrated
to induce bone formation in vitro and ectopic bone formation in
vivo, while hLMP-2 is not osteoinductive, suggesting that LIM
domains are not essential for this function. Thus it has been
hypothesized that the osteoinductive domain could reside in the
Unique region that is partially conserved in hLMP-3. To examine
the osteoinductive properties of this minimal domain we have cloned
three different length of the Unique region of the hLMP-3 gene,
corresponding to 120, 90 and 60 bp, fused to the enhanced green
fluorescent protein (eGFP) and named L40-eGFP, L30-eGFP and
L20-eGFP respectively. Thus we tested the ability of these
constructs to induce bone specific gene expression and bone
mineralization in vitro and ectopic bone formation in vivo in
comparison to the full-length gene hLMP-3. Here we demonstrate
that adenoviral-mediated gene transfer of all the 3 domains induces
expression of certain bone-specific genes in a mouse fibroblasts cell
line. The up-regulation of osteo-specific genes was assessed in mouse
fibroblasts also by means of biolistic transfection using a plasmid
containing a L20-eGFP fusion gene. In addition, we demonstrate
that all the domains are able to induce mineralization in fibroblast
and mesenchymal stem cells. An experiment to evaluate if direct
gene transfer of the three constructs into murine skeletal muscle
results in ectopic bone formation as efficiently as using LMP-3 is
being performed. Finally in order to propose these new constructs
as an effective approach to induce bone formation in vivo for clinical
applications, we have synthesized a peptide of 20 aminoacid,
corresponding to the fragment of 60 bp of the Unique region (named
PTD-OD-1). The peptide enter the cells by a protein transduction
domain (PTD-5) and its ability to induce in vitro expression of
bone-specific genes and bone mineralization both in fibroblast and
in human mesenchymal stem cells will be evaluated. PTD-OD-1
could represent a safe and powerful tool for clinical applications,
and merit several analysis to evaluate its ability
Ex Vivo Gene Therapy Approach Using Human Lim Mineralization Protein-3 To Induce Bone Healing in a Rodent Model
No full textIntroduction. Gene therapy research in the field of orthopaedics have evolved during the last decade, leading to possible applications for the treatment of pathological conditions, such as bone fractures and defects. Several gene transfer techniques have been employed so far for inducing bone formation in animal models of bone defects. Cell-based approaches, such as the implantation in animals of ex vivo genetically modified cells, produced promising results. In this study we used autologous skin fibroblasts, which are very simple to harvest and propagate in culture, transduced ex vivo with the osteogenic factor Lim Mineralization Protein-3 (LMP-3). These engineered cells produced successful bone healing when implanted by the use of a scaffold in rats, validating the in vivo osteoinductive properties of hLMP-3. Materials and Methods. Primary dermal fibroblasts cultures were established using a biopsy of shaved skin obtained from the abdomen of each rat. Semi-confluent primary fibroblasts were infected with either AdBMP-2 or AdhLMP-3, using a overall multiplicity of infection (MOI) of 100 viral particles per cell. Cells transduced with Ad-eGFP were used as a viral infection control, while untreated cells served as a negative control. The transduced cells were harvested 24 hours after viral infection, let adsorbed on a Hydroxyapatite/Collagen scaffold and then implanted in a bone defect surgically performed in the mandible of immunocompetent rats. The animals were divided in 4 groups: rats treated with cells infected with AdLMP-3, rats treated with cells infected with AdBMP-2, rats treated with cells infected with Ad-eGFP and rats treated with untreated cells. Rats from each group were sacrified at 1, 2 and 3 months after the treatment and studied by x-rays, Micro-CT and histology. Results. All the animals treated with LMP-3 showed healing of the bone defect after 3 months, as confirmed histologically and radiographically. On the contrary none of the controls showed bone formation at the latest time point. Discussion. Recently, Lim Mineralization Proteins (LMP) have been identified as regulators of the osteoblast differentiation program. We have previously demonstrated that human LMP-3 contributes actively to bone formation, acting through the BMP-2 signaling pathway, being capable of inducing differentiation of cells of mesenchymal derivation towards the osteoblastic lineage, through the up-regulation of bone-specific genes, along with ectopic bone formation in vivo and mineralization in vitro. In this study we have tested the efficacy of an ex-vivo approach using autologous dermal fibroblasts infected with AdLMP-3. Our results show that it s possible to induce a complete bone healing using this method, and confirm the in vivo osteoinductive properties of hLMP-3
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
IL-12p70 and IL-18 gene-modified dendritic cells loaded with tumor antigen-derived peptides or recombinant protein effectively stimulate specific Type-1 CD4+ T-cell responses from normal donors and melanoma patients in vitro.
No full textAlthough CD4(+) Type-1T helper (Th1) cells secreting interferon-gamma (IFN-gamma) appear to play an essential role in promoting durable antitumor immunity, we have previously shown that patients with cancer exhibit dysfunctional Th1-type responses against epitopes derived from tumor antigens, such as MAGE-A6. Here, we engineered human dendritic cells (DCs) to secrete high levels of the IFN-gamma-inducing cytokines, interleukin (IL)-12p70 and IL-18, via recombinant adenoviral infection to generate an in vitro stimulus capable of promoting previously deficient patient Th1-type responses. Dendritic cells co- infected with Ad. IL-12 and Ad. IL-18 (DC. IL-12/18) were more effective at stimulating MAGE-A6-specific Th1-type CD4(+) T-cell responses than DCs infected with either of the cytokine vectors alone, control Ad. C5 virus or uninfected DCs. Furthermore, we show that DC. IL-12/18 loaded with recombinant MAGE-A6 protein (rMAGE) and used as in vitro stimulators promote Th1-type immunity that is frequently directed against multiple MAGE-A6-derived epitopes. The superiority of DC. IL-12/18-based stimulations in melanoma patients was independent of disease stage or current disease status. Based on these results, we believe this modality may prove clinically useful as a vaccine platform to promote the recovery of tumor antigen-specific, Th1-type CD4(+) T-cell responses in patients with cancer
Ex Vivo Gene Therapy Approach Using Human Lim Mineralization Protein-3 To Induce Bone Healing in a Rodent Model
No full textIntroduction. Gene therapy research in the field of orthopaedics have evolved during the last decade, leading to possible applications for the treatment of pathological conditions, such as bone fractures and defects. Several gene transfer techniques have been employed so far for inducing bone formation in animal models of bone defects. Cell-based approaches, such as the implantation in animals of ex vivo genetically modified cells, produced promising results. In this study we used autologous skin fibroblasts, which are very simple to harvest and propagate in culture, transduced ex vivo with the osteogenic factor Lim Mineralization Protein-3 (LMP-3). These engineered cells produced successful bone healing when implanted by the use of a scaffold in rats, validating the in vivo osteoinductive properties of hLMP-3. Materials and Methods. Primary dermal fibroblasts cultures were established using a biopsy of shaved skin obtained from the abdomen of each rat. Semi-confluent primary fibroblasts were infected with either AdBMP-2 or AdhLMP-3, using a overall multiplicity of infection (MOI) of 100 viral particles per cell. Cells transduced with Ad-eGFP were used as a viral infection control, while untreated cells served as a negative control. The transduced cells were harvested 24 hours after viral infection, let adsorbed on a Hydroxyapatite/Collagen scaffold and then implanted in a bone defect surgically performed in the mandible of immunocompetent rats. The animals were divided in 4 groups: rats treated with cells infected with AdLMP-3, rats treated with cells infected with AdBMP-2, rats treated with cells infected with Ad-eGFP and rats treated with untreated cells. Rats from each group were sacrified at 1, 2 and 3 months after the treatment and studied by x-rays, Micro-CT and histology. Results. All the animals treated with LMP-3 showed healing of the bone defect after 3 months, as confirmed histologically and radiographically. On the contrary none of the controls showed bone formation at the latest time point. Discussion. Recently, Lim Mineralization Proteins (LMP) have been identified as regulators of the osteoblast differentiation program. We have previously demonstrated that human LMP-3 contributes actively to bone formation, acting through the BMP-2 signaling pathway, being capable of inducing differentiation of cells of mesenchymal derivation towards the osteoblastic lineage, through the up-regulation of bone-specific genes, along with ectopic bone formation in vivo and mineralization in vitro. In this study we have tested the efficacy of an ex-vivo approach using autologous dermal fibroblasts infected with AdLMP-3. Our results show that it s possible to induce a complete bone healing using this method, and confirm the in vivo osteoinductive properties of hLMP-3
Early Transcriptional Events During Osteogenic Differentiation of Human Bone Marrow Stromal Cells Induced by Lim Mineralization Protein 3
No full textLim mineralization protein-3 (LMP3) induces osteoblast differentiation by regulating the expression and activity of certain molecules involved in the osteogenic cascade, including those belonging to the bone morphogenetic protein (BMP) family. The complete network of molecular events involved in LMP3-mediated osteogenesis is still unknown. The aim of this study was to analyze the genome-wide gene expression profiles in human mesenchymal stem cells (hMSC) induced by exogenous LMP3 to mediate osteogenesis. For this purpose hMSC were transduced with a defective adenoviral vector expressing the human LMP3 gene and microarray analysis was performed 1 day post-adenoviral transduction. Cells transduced with the vector backbone and untransduced cells were used as independent controls in the experiments. Microarray data were independently validated by means of real-time PCR on selected transcripts. The statistical analysis of microarray data produced a list of 263 significantly (p < 0.01) differentially expressed transcripts. The biological interpretation of the results indicated, among the most noteworthy effects, the modulation of genes involved in the TGF-beta1 pathway: 88 genes coding for key regulators of the cell cycle regulatory machinery and 28 genes implicated in the regulation of cell proliferation along with the development of connective, muscular, and skeletal tissues. These results suggested that LMP3 could affect the fine balance between cell proliferation/differentiation of mesenchymal cells mostly by modulating the TGF-beta1 signaling pathway
Efficient bone formation by gene transfer of human LIM mineralization protein-3
No full textLIM mineralization protein (LMP) is a novel positive regulator of the osteoblast differentiation program. In humans, three different LMP splice variants have been identified: LMP-1, LMP-2, and LMP-3. Gene transfer of human LMP-1 (hLMP-1) induces expression of genes involved in bone formation, including certain bone morphogenetic proteins (BMPs), promotes bone nodule formation in vitro, ectopic bone formation in vivo, and is therapeutic in animal models of posterior thoracic and lumbar spine fusion. To examine the osteoinductive properties of the LMP-3 in vitro and in vivo, we have generated plasmid and adenoviral vectors expressing codon-optimized hLMP-3. Here we demonstrate that gene transfer of hLMP-3 induces expression of the bone-specific genes osteocalcin, osteopontin, and bone sialoprotein and induced bone mineralization in preosteoblastic and fibroblastic cells. We also demonstrate that hLMP-3 is able to induce bone mineralization and the expression of the bone-specific genes, BMP-2, OSX, RunX2, and alkaline phosphatase in human mesenchymal stem cells in a dose-dependent manner. Finally, we demonstrate that direct gene transfer of hLMP-3 into murine skeletal muscle results in ectopic bone formation more efficiently than BMP-2. These results demonstrate that hLMP-3 gene transfer can be used to promote bone formation in cell culture and in vivo as or more efficiently than BMP-2, thus establishing feasibility and efficacy of direct gene delivery of hLMP-3 to produce bone in vivo. These results suggest that gene transfer of hLMP-3 could be developed as a bone-inductive therapeutic agent for clinical applications
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