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Our understanding of the molecular mechanisms of many neurological disorders has been greatly enhanced by the discovery of mutations in genes linked to familial forms of these diseases. These have facilitated the generation of cell and animal models that can be used to understand the underlying molecular pathology. Recently, there has been a surge of interest in the use of patient-derived cells, due to the development of induced pluripotent stem cells and their subsequent differentiation into neurons and glia. Access to patient cell lines carrying the relevant mutations is a limiting factor for many centres wishing to pursue this research. We have therefore generated an open-access collection of fibroblast lines from patients carrying mutations linked to neurological disease. These cell lines have been deposited in the National Institute for Neurological Disorders and Stroke (NINDS) Repository at the Coriell Institute for Medical Research and can be requested by any research group for use in in vitro disease modelling. There are currently 71 mutation-defined cell lines available for request from a wide range of neurological disorders and this collection will be continually expanded. This represents a significant resource that will advance the use of patient cells as disease models by the scientific community.

Distinguishing Burkitt lymphoma (BL) from B cell lymphoma, unclassifiable with features intermediate between diffuse large B-cell lymphoma (DLBCL) and BL (DLBCL/BL), and DLBCL is challenging. We propose an immunohistochemistry and fluorescent in situ hybridization (FISH) based scoring system that is employed in three phases - Phase 1 (morphology with CD10 and BCL2 immunostains), Phase 2 (CD38, CD44 and Ki-67 immunostains) and Phase 3 (FISH on paraffin sections for MYC, BCL2, BCL6 and immunoglobulin family genes). The system was evaluated on 252 aggressive B-cell lymphomas from Europe and from sub-Saharan Africa. Using the algorithm, we determined a specific diagnosis of BL or not-BL in 82%, 92% and 95% cases at Phases 1, 2 and 3, respectively. In 3·4% cases, the algorithm was not completely applicable due to technical reasons. Overall, this approach led to a specific diagnosis of BL in 122 cases and to a specific diagnosis of either DLBCL or DLBCL/BL in 94% of cases that were not diagnosed as BL. We also evaluated the scoring system on 27 cases of BL confirmed on gene expression/microRNA expression profiling. Phase 1 of our scoring system led to a diagnosis of BL in 100% of these cases.

Only three cases of lymphoepithelioma-like carcinoma of the endometrium have been reported to date. We present a new case in a 67-year-old woman involving an exophytic mass that caused postmenopausal bleeding. Histologically, undifferentiated carcinomatous areas were intermingled with abundant lymphoid tissue. Epstein-Barr virus was not detected in either neoplastic or lymphoid cells.

The nipple is an unusual site of cutaneous melanoma with only few cases described in literature. We herein report an additional case of malignant melanoma arising on the nipple of a 47-year old woman. The nodular, ulcerated lesion was removed surgically and the diagnosis was that of a vertical growth phase melanoma. The melanocytic origin of the tumour was confirmed by immunohistochemistry. The case pursued a poor clinical outcome with distant metastases and death of the patient.

Heterotopic pancreas tissue in the gallbladder is a rare benign condition with no clinical relevance and found incidentally in most cases. Only 28 cases of heterotopic pancreas are reported until 2007 in the worldwide literature. The preoperative diagnosis is very hard, so that it could be considered in differential diagnosis with other benign and malignant disease of gallbladder and biliary tree. The surgical approach for the excision of a undefined lesion and the histological identification is a correct procedure in suspect case. We report 2 cases of heterotopic pancreatic tissue of the gallbladder.

Multiple hamartomas of the lung are uncommon. The few cases described to date are multiple parenchymal hamartomas or multiple endobronchial and parenchymal hamartomas. Herein, an original case is described which is characterized by the association between an endobronchial hamartoma and multiple, unusual, bronchial lesions of the peripheral lung.

Primitive neuroectodermal tumors of the hand are extremely rare, and only 5 cases have been described to date. Here, we report a case of a 35 year-old male who presented a progressive swelling on the palm of his right hand. Clinical examination showed a solid mass and X-ray revealed a soft tissue mass. Magnetic resonance imaging (MRI) revealed infiltrated interosseous muscles, metacarpal bones and tendons. The patient underwent surgery and the lesion was removed. On the basis of morphological, immunohistochemical and molecular biology findings, a diagnosis of primitive neuroctodermal tumor was made.

The term pseudolymphoma refers to a heterogeneous group of benign reactive T-cell or B-cell lymphoproliferative processes of diverse causes that simulate lymphoma clinically and histologically but usually undergo spontaneous remission. Its pathogenesis is still unclear. The prognosis is good although some evidence suggests that pseudolymphoma may progress to lymphoma. Pseudolymphoma of the urinary tract is extremely rare. We herein report a case of pseudolymphoma of the renal sinus in a 70-year-old man, associated with a high grade urothelial carcinoma of the bladder and to a prostatic adenocarcinoma (Gleason score 6). A brief review of the literature is included. The kidney showed a well-defined, whitish soft mass which involved the renal sinus. Microscopically, the lesion of the renal sinus consisted of a proliferation of small to medium size lymphocytes (CD20 positive and Bcl-2 negative) sometimes arranged in hyperplastic follicular structures. The diagnosis was confirmed by molecular studies which showed an oligopolyclonal IgH rearrangement. To the best of our knowledge, this is the second case of pseudolymphoma with a complete molecular characterization ever described in the renal sinus and the first one associated with multiple urogenital carcinomas.

A case of primary linitis plastica of the colon is presented. This case is of interest for three reasons: the site of origin in the right colon (80% of cases reported develop distally to the splenic flexure), a biopsy previously taken from the mucosa demonstrated the presence of a signet ring cell carcinoma (endoscopic biopsies do not provide a conclusive diagnosis in the majority of cases reported) and hyaline with sparse amyloid nodules were detected in the extensive, dense fibrous tissue intermingled with tumour cells.

BACKGROUND: Recent evidence suggests that lipid pathway is altered in many human tumours. In Burkitt lymphoma this is reflected by the presence of lipid droplets which are visible in the cytoplasm of neoplastic cells in cytological preparations. These vacuoles are not identifiable in biopsy section as lipids are "lost" during tissue processing. METHODS AND RESULTS: In this study we investigated the expression of genes involved in lipid metabolism, at both RNA and protein level in Burkitt lymphoma and in other B-cell aggressive lymphoma cases. Gene expression profile indicated a significant over-expression of the adipophilin gene and marked up-regulation of other genes involved in lipid metabolism in Burkitt lymphoma. These findings were confirmed by immunohistochemistry on a series od additional histological samples: 45 out of 47 BL cases showed strong adipophilin expression, while only 3 cases of the 33 of the not-Burkitt lymphoma category showed weak adipophilin expression (p

DACH1 is the human homolog of the Drosophila dachshund gene, which is involved in the development of the eye, nervous system, and limbs in the fly. Here, we systematically investigate DACH1 expression patterns during human neurodevelopment, from 5 to 21 postconceptional weeks. By immunodetection analysis, we found that DACH1 is highly expressed in the proliferating neuroprogenitors of the developing cortical ventricular and subventricular regions, while it is absent in the more differentiated cortical plate. Single-cell global transcriptional analysis revealed that DACH1 is specifically enriched in neuroepithelial and ventricular radial glia cells of the developing human neocortex. Moreover, we describe a previously unreported DACH1 expression in the human striatum, in particular in the striatal medium spiny neurons. This finding qualifies DACH1 as a new striatal projection neuron marker, together with PPP1R1B, BCL11B, and EBF1. We finally compared DACH1 expression profile in human and mouse forebrain, where we observed spatio-temporal similarities in its expression pattern thus providing a precise developmental description of DACH1 in the 2 mammalian species.

We describe the use of DNA transposons as tools for carrying out functional screenings in murine embryonic stem (ES) cell-derived neural stem (NS) cells. NS cells are a new type of stem cells featuring radial glial properties, that undergoes symmetric cell division for an indefinite number of passages, expanding as a monolayer. In this model, the previously unreported Sleeping Beauty transposase M3A achieves an optimal blend of clone generation efficiency and low redundancy of integrations per clone, compared to the SB100X Sleeping Beauty variant and to the piggyBac transposon. The technology described here makes it possible to randomly trap genes in the NS cell genome and modify their expression or tag them with fluorescent markers and selectable genes, allowing recombinant cells to be isolated and expanded clonally. This approach will facilitate the identification of novel determinants of stem cell biology and neural cell fate specification in NS cells.

Il saggio, dopo aver sviluppato il tema inerente la cartografia storica su Roma, espone i risultati di una lunga ricerca, coordinata da Paolo Micalizzi, finalizzata alla realizzazione e messa in rete di un sofisticato sistema informativo geografico sul centro storico di Roma, denominato Descriptio Romae WebGIS. The essay, having developed the theme concerning the historical maps of Rome, expounds the results of an extensive research, coordinated by Paolo Micalizzi, aimed at the creation and networking of a sophisticated geographic information system on the historic center of Rome, called Descriptio Romae WebGIS.

The possibility of generating neural stem/precursor cells (NPCs) from induced pluripotent stem cells (iPSCs) has opened a new avenue of research that might nurture bench-to-bedside translation of cell transplantation protocols in central nervous system myelin disorders. Here we show that mouse iPSC-derived NPCs (miPSC-NPCs)-when intrathecally transplanted after disease onset-ameliorate clinical and pathological features of experimental autoimmune encephalomyelitis, an animal model of multiple sclerosis. Transplanted miPSC-NPCs exert the neuroprotective effect not through cell replacement, but through the secretion of leukaemia inhibitory factor that promotes survival, differentiation and the remyelination capacity of both endogenous oligodendrocyte precursors and mature oligodendrocytes. The early preservation of tissue integrity limits blood-brain barrier damage and central nervous system infiltration of blood-borne encephalitogenic leukocytes, ultimately responsible for demyelination and axonal damage. While proposing a novel mechanism of action, our results further expand the therapeutic potential of NPCs derived from iPSCs in myelin disorders.

High Mobility Group A proteins (HMGA1 and HMGA2) are architectural nuclear factors involved in development, cell differentiation, and cancer formation and progression. Here we report the cloning, developmental expression and functional analysis of a new multi-AT-hook factor in Xenopus laevis (XHMG-AT-hook) that exists in three different isoforms. Xhmg-at-hook1 and 3 isoforms, but not isoform 2, are expressed throughout the entire development of Xenopus, both in the maternal and zygotic phase. Localized transcripts are present in the animal pole in the early maternal phase; during the zygotic phase, mRNA can be detected in the developing central nervous system (CNS), including the eye, and in the neural crest. We show evidence that XHMG-AT-hook proteins differ from typical HMGA proteins in terms of their properties in DNA binding and in protein/protein interaction. Finally, we provide evidence that they are involved in early CNS development and in neural crest differentiation.

Neural stem (NS) cells are a self-renewing population of symmetrically dividing multipotent radial glia-like stem cells, characterized by homogeneous expansion in monolayer. Here we report that fetal NS cells isolated from different regions of the developing mouse nervous system behave in a similar manner with respect to self-renewal and neuropotency, but exhibit distinct positional identities. For example, NS cells from the neocortex maintain the expression of anterior transcription factors, including Otx2 and Foxg1, while Hoxb4 and Hoxb9 are uniquely found in spinal cord-derived NS cells. This molecular signature was stable for over 20 passages and was strictly linked to the developmental stage of the donor, because only NS cells derived from E14.5 cortex, and not those derived from E12.5 cortex, carried a consistent transcription factor profile. We also showed that traits of this positional code are maintained during neuronal differentiation, leading to the generation of electrophysiologically active neurons, even if they do not acquire a complete neurochemical identity.

We report 3 cases of lymphoid neoplasms with mixed lineage features of T-, NK-, or B-cell marker expression and clonal gene rearrangement for both T-cell receptor and immunoglobulin light chain IgK. A characteristic of our cases was the lack of expression of the specific B-cell transcription factor, Pax5, which is essential for maintaining the identity and function of mature B cells during late B lymphopoiesis. In the absence of Pax5, B cells in vitro can differentiate into macrophages, dendritic cells, granulocytes, and T/NK cells. Methylation analysis of the Pax5 gene in our cases suggests that its inactivation by this epigenetic event in a committed or mature B cell, before plasma cell differentiation, may well be a common pathogenetic mechanism in mature lymphoid neoplasms with expression of multilineage antigens. In particular, case 1 may represent a mixed NK- and B-cell lineage; and cases 2 and 3 may represent mixed T and B-cell lineage, respectively. Aberrations in the DNA methylation patterns are currently recognized as a hallmark of human cancer. Cases with aberrant phenotypes require molecular analysis for lineage assignment. Studies of such cases may be helpful to better elucidate whether they represent a distinct entity with clinical, immunophenotypic, and molecular characteristics or an incidental phenomenon during malignant transformation. Interestingly, these cases were all characterized by poor clinical outcome.

Background Otx genes, orthologues of the Drosophila orthodenticle gene (otd), play crucial roles in vertebrate brain development. In the Xenopus eye, Xotx2 and Xotx5b promote bipolar and photoreceptor cell fates, respectively. The molecular basis of their differential action is not completely understood, though the carboxyl termini of the two proteins seem to be crucial. To define the molecular domains that make the action of these proteins so different, and to determine whether their retinal abilities are shared by Drosophila OTD, we performed an in vivo molecular dissection of their activity by transfecting retinal progenitors with several wild-type, deletion and chimeric constructs of Xotx2, Xotx5b and otd. Results We identified a small 8–10 amino acid divergent region, directly downstream of the homeodomain, that is crucial for the respective activities of XOTX2 and XOTX5b. In lipofection experiments, the exchange of this 'specificity box' completely switches the retinal activity of XOTX5b into that of XOTX2 and vice versa. Moreover, the insertion of this box into Drosophila OTD, which has no effect on retinal cell fate, endows it with the specific activity of either XOTX protein. Significantly, in cell transfection experiments, the diverse ability of XOTX2 and XOTX5b to synergize with NRL, a cofactor essential for vertebrate rod development, to transactivate the rhodopsin promoter is also switched depending on the box. We also show by GST-pull down that XOTX2 and XOTX5b differentially interact with NRL, though this property is not strictly dependent on the box. Conclusion Our data provide molecular evidence on how closely related homeodomain gene products can differentiate their functions to regulate distinct cell fates. A small 'specificity box' is both necessary and sufficient to confer on XOTX2 and XOTX5b their distinct activities in the developing frog retina and to convert the neutral orthologous OTD protein of Drosophila into a positive and specific XOTX-like retinal regulator. Relatively little is known of what gives developmental specificity to homeodomain regulators. We propose that this box is a major domain of XOTX proteins that provides them with the appropriate developmental specificity in retinal histogenesis.

HMGA proteins are "architectural modifiers" of the chromatin, characterized by three conserved "AT-hook" motifs, with which they bind AT-rich regions of the DNA, to assist in gene transcription. We report the identification and developmental expression of Xenopus laevis hmga2beta (Xlhmga2beta). We provide evidence of two forms of hmga2 (Xlhmga2alpha and Xlhmga2beta) and of a splicing variant for Xlhmga2beta with an additional AT-hook. By comparing X. laevis and X. tropicalis hmga2 DNA sequences to those of other organisms we show a high conservation of the Xlhmga2beta variant. By RT-PCR, Xlhmga2beta transcripts are first detected before the midblastula transition (MBT), and then become more abundant. By in situ hybridization, localized transcripts are first detected at neurula stages, in the presumptive central nervous system (CNS). At tailbud and tadpole stages, Xlhmga2beta mRNA is detected in the CNS, in the otic vesicles, in neural crest cell derivatives, in the notochord, and in the medio-lateral mesoderm.

C’è ancora molto di incerto nelle esperienze solitamente rubricate sotto l’espressione “media education”, e comunque nell’impatto delle nuove generazioni con i nuovi sistemi di comunicazione emergono nuove esigenze. Non si tratta di cercare soltanto nuovi modelli educativi – compito, anche questo interessante e lodevole, ma di prospettare nuove modalità di ricerca attorno ai modelli educativi e quindi, proprio per questo, nuovi approcci pedagogici. Dall’incontro con le tecnologie della informazione e della comunicazione la persona trae non soltanto strumenti, possibilità, ed opportunità, ma anche un contesto dinamico di riferimento entro il quale va a riscrivere motivazioni e bisogni, attese e prospettive, connotazioni e criteri… Il discorso sulle competenze e sui criteri educativi diventa così un pretesto per giungere a questioni propriamente pedagogiche (e non soltanto educative) e didattiche. Nel saggio la didattica si connota come disciplina destinata a studiare lo spazio di possibile mediazione fra obiettivi assegnati all’educazione e compiti di sviluppo assunti dalla persona; una mediazione da esercitarsi con gli strumenti della negoziazione e con le regole (criteri) che disciplinano la decisione e la scelta dell’insegnante. Non c’è più spazio per una didattica che non si configuri come scienza e che non si proietti verso il futuro con la determinazione che deriva dalla consapevolezza del rilievo dei compiti che le sono propri.