153 research outputs found

    Initial experience related to the use of the Cosman-Roberts-Wells stereotactic instrument

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    Journal ArticleInitial experience with a new arc-radius design of stereotactic frame that interfaced with the existing components of the Brown-Roberts-Wells instrument is reported. Over a 6-month period, 32 procedures were performed on 23 males and nine female patients (mean age 32 years); these included 27 stereotactic biopsy procedures, two stereotactic implantations of cyst catheter reservoirs, two ventriculoscopic aspirations of third ventricular colloid cysts, and one stereotactic aspiration of a craniopharyngioma. In all cases successful targeting was achieved and verified by postoperative computerized tomography. There were no operation-related complications. This new frame offers rapid and accurate targeting and is a useful adjunct to the stereotactic armamentarium

    Management of cysticercosis cerebri

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    Journal ArticleInfestation of the central nervous system (CNS) with the parasitic larval form of the cestode Taenia solium, Cysticercosis Cerebri represents an endemic problem in much of the underdeveloped world. In such areas, up to 4% of the population maybe affected by neurocysticercosis, and it accounts for up to 11% of neurosurgical procedures performed in selected centers. The disease remains endemic in Central and South America, Mexico, Eastern Europe, and Asia. With an increasing immigrant influx, however, more cases of this enigmatic entity will be presenting to neurosurgeons in developed nations; therefore maintaining a high index of suspicion in persons of appropriate ethnic background, and recognizing the potential disease spectrum is paramount for all neurosurgeons

    Utilization of unilateral and bilateral stereotactically placed adrenomedullary-striatal autografts in Parkinsonian humans: rationale, techniques, and observations

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    Journal ArticleA limited clinical pilot study involving an amalgam of specialized disciplines including neurology, neuropharmacology, neuropsychology, neurosurgery, neuroanesthesia, neuroradiology, surgical pathology, neuropathology, and urological surgery was organized to clarify issues related to patient selection, optimization of grafting materials, design of a safe, effective, standardized, and reproducible surgical technique, and possible modification of clinical patterns. After initial assessment of 82 Parkinsonian patients for periods of 6 to 20 months, 10 (age, 39-68 years) were selected for unilateral or bilateral adrenomedullary autografts to the caudate nucleus with ependymal and cerebrospinal fluid contact, employing image-directed stereotactic methods. Selection was made only after clear definition of clinical pattern and optimization of medication responses

    Microenvironment in neuroblastoma: Isolation and characterization of tumor-derived mesenchymal stromal cells

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    Background: It has been proposed that mesenchymal stromal cells (MSCs) promote tumor progression by interacting with tumor cells and other stroma cells in the complex network of the tumor microenvironment. We characterized MSCs isolated and expanded from tumor tissues of pediatric patients diagnosed with neuroblastomas (NB-MSCs) to define interactions with the tumor microenvironment. Methods: Specimens were obtained from 7 pediatric patients diagnosed with neuroblastoma (NB). Morphology, immunophenotype, differentiation capacity, proliferative growth, expression of stemness and neural differentiation markers were evaluated. Moreover, the ability of cells to modulate the immune response, i.e. inhibition of phytohemagglutinin (PHA) activated peripheral blood mononuclear cells (PBMCs) and natural killer (NK) cytotoxic function, was examined. Gene expression profiles, known to be related to tumor cell stemness, Wnt pathway activation, epithelial-mesenchymal transition (EMT) and tumor metastasis were also evaluated. Healthy donor bone marrow-derived MSCs (BM-MSC) were employed as controls. Results: NB-MSCs presented the typical MSC morphology and phenotype. They showed a proliferative capacity superimposable to BM-MSCs. Stemness marker expression (Sox2, Nanog, Oct3/4) was comparable to BM-MSCs. NB-MSC in vitro osteogenic and chondrogenic differentiation was similar to BM-MSCs, but NB-MSCs lacked adipogenic differentiation capacity. NB-MSCs reached senescence phases at a median passage of P7 (range, P5-P13). NB-MSCs exhibited greater immunosuppressive capacity on activated T lymphocytes at a 1:2 (MSC: PBMC) ratio compared with BM-MSCs (p = 0.018). NK cytotoxic activity was not influenced by co-culture, either with BM-MSCs or NB-MSCs. Flow-cytometry cell cycle analysis showed that NB-MSCs had an increased number of cells in the G0-G1 phase compared to BM-MSCs. Transcriptomic profiling results indicated that NB-MSCs were enriched with EMT genes compared to BM-MSCs. Conclusions: We characterized the biological features, the immunomodulatory capacity and the gene expression profile of NB-MSCs. The NB-MSC gene expression profile and their functional properties suggest a potential role in promoting tumor escape, invasiveness and metastatic traits of NB cancer cells. A better understanding of the complex mechanisms underlying the interactions between NB cells and NB-derived MSCs should shed new light on potential novel therapeutic approaches

    Combined platelet-rich plasma and lipofilling treatment provides great improvement in facial skin-induced lesion regeneration for scleroderma patients

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    Background: The use of stem cells, including mesenchymal stem cells (MSCs), for regenerative medicine is gaining interest for the clinical benefits so far obtained in patients. This study investigates the use of adipose autologous tissue in combination with platelet-rich plasma (PRP) to improve the clinical outcome of patients affected by systemic sclerosis (SSc). Methods: Adipose-derived mesenchymal stem cells (AD-MSCs) and PRPs were purified from healthy donors and SSc patients. The multilineage differentiation potential of AD-MSCs and their genotypic-phenotypic features were investigated. A cytokine production profile was evaluated on AD-MSCs and PRPs from both healthy subjects and SSc patients. The adipose tissue-derived cell fraction, the so-called stromal vascular fraction (SVF), was coinjected with PRP in the perioral area of SSc patients. Results: Histopathological and phenotypical analysis of adipose tissue from SSc patients revealed a disorganization of its distinct architecture coupled with an altered cell composition. Although AD-MSCs derived from SSc patients showed high multipotency, they failed to sustain a terminally differentiated progeny. Furthermore, SVFs derived from SSc patients differed from healthy donors in their MSC-like traits coupled with an aberrant cytokine production profile. Finally, the administration of PRP in combination with autologous SVF improved buccal's rhyme, skin elasticity and vascularization for all of the SSc patients enrolled in this study. Conclusions: This innovative regenerative therapy could be exploited for the treatment of chronic connective tissue diseases, including SSc

    IL4 primes the dynamics of breast cancer progression via DUSP4 inhibition

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    The tumor microenvironment supplies proinflammatory cytokines favoring a permissive milieu for cancer cell growth and invasive behavior. Here we show how breast cancer progression is facilitated by IL4 secreted by adipose tissue and estrogen receptor-positive and triple-negative breast cancer cell types. Blocking autocrine and paracrine IL4 signaling with the IL4R\uce\ub1 antagonist IL4DM compromised breast cancer cell proliferation, invasion, and tumor growth by downregulating MAPK pathway activity. IL4DM reduced numbers of CD44+/CD24-cancer stem-like cells and elevated expression of the dual specificity phosphatase DUSP4by inhibiting NF-\uce\ubaB. Enforced expression of DUSP4 drove conversion of metastatic cells to nonmetastatic cells. Mechanistically, RNAi-mediated attenuation of DUSP4activated the ERKand p38 MAPK pathways, increased stem-like properties, and spawned metastatic capacity. Targeting IL4 signaling sensitized breast cancer cells to anticancer therapy and strengthened immune responses by enhancing the number of IFN\uce\ub3-positive CTLs. Our results showed the role of IL4 in promoting breast cancer aggressiveness and how its targeting may improve the efficacy of current therapies

    Multifunctional metal matrix composites with embedded printed electrical materials fabricated by Ultrasonic Additive Manufacturing

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    This work proposes a new method for the fabrication of Multifunctional Metal Matrix Composite (MMC) structures featuring embedded printed electrical materials through Ultrasonic Additive Manufacturing (UAM). Printed electrical circuitries combining conductive and insulating materials were directly embedded within the interlaminar region of UAM aluminium matrices to realise previously unachievable multifunctional composites. A specific surface flattening process was developed to eliminate the risk of short circuiting between the metal matrices and printed conductors, and simultaneously reduce the total thickness of the printed circuitry. This acted to improve the integrity of the UAM MMC’s and their resultant mechanical strength. The functionality of embedded printed circuitries was examined via four-point probe measurement. DualBeam Scanning Electron Microscopy (SEM) and Focused Ion Beam (FIB) milling were used to investigate the microstructures of conductive materials to characterize the effect of UAM embedding energy whilst peel testing was used to quantify mechanical strength of MMC structures in combination with optical microscopy. Through this process, fully functioning MMC structures featuring embedded insulating and conductive materials were realised whilst still maintaining high peel resistances of ca. 70 N and linear weld densities of ca. 90%

    Targeting chemoresistant colorectal cancer via systemic administration of a BMP7 variant

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    Despite intense research and clinical efforts, patients affected by advanced colorectal cancer (CRC) have still a poor prognosis. The discovery of colorectal (CR) cancer stem cell (CSC) as the cell compartment responsible for tumor initiation and propagation may provide new opportunities for the development of new therapeutic strategies. Given the reduced sensitivity of CR-CSCs to chemotherapy and the ability of bone morphogenetic proteins (BMP) to promote colonic stem cell differentiation, we aimed to investigate whether an enhanced variant of BMP7 (BMP7v) could sensitize to chemotherapy-resistant CRC cells and tumors. Thirty-five primary human cultures enriched in CR-CSCs, including four from chemoresistant metastatic lesions, were used for in vitro studies and to generate CR-CSC-based mouse avatars to evaluate tumor growth and progression upon treatment with BMP7v alone or in combination with standard therapy or PI3K inhibitors. BMP7v treatment promotes CR-CSC differentiation and recapitulates the cell differentiation-related gene expression profile by suppressing Wnt pathway activity and reducing mesenchymal traits and survival of CR-CSCs. Moreover, in CR-CSC-based mouse avatars, BMP7v exerts an antiangiogenic effect and sensitizes tumor cells to standard chemotherapy regardless of the mutational, MSI, and CMS profiles. Of note, tumor harboring PIK3CA mutations were affected to a lower extent by the combination of BMP7v and chemotherapy. However, the addition of a PI3K inhibitor to the BMP7v-based combination potentiates PIK3CA-mutant tumor drug response and reduces the metastatic lesion size. These data suggest that BMP7v treatment may represent a useful antiangiogenic and prodifferentiation agent, which renders CSCs sensitive to both standard and targeted therapies

    Elimination of quiescent/slow-proliferating cancer stem cells by Bcl-XL inhibition in non-small cell lung cancer

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    Lung cancer is the most common cause of cancer-related mortality worldwide, urging the discovery of novel molecular targets and therapeutic strategies. Stem cells have been recently isolated from non-small cell lung cancer (NSCLC), thus allowing the investigation of molecular pathways specifically active in the tumorigenic population. We have found that Bcl-XL is constantly expressed by lung cancer stem cells (LCSCs) and has a prominent role in regulating LCSC survival. Whereas chemotherapeutic agents were scarcely effective against LCSC, the small molecule Bcl-2/Bcl-XL inhibitor ABT-737, but not the selective Bcl-2 inhibitor ABT-199, induced LCSC death at nanomolar concentrations. Differently from gemcitabine, which preferentially eliminated proliferating LCSC, ABT-737 had an increased cytotoxic activity in vitro towards quiescent/slow-proliferating LCSC, which expressed high levels of Bcl-XL. In vivo, ABT-737 as a single agent was able to inhibit the growth of LCSC-derived xenografts and to reduce cancer stem cell content in treated tumors. Altogether, these results indicate that quiescent/slow-proliferating LCSC strongly depend on Bcl-XL for their survival and indicate Bcl-XL inhibition as a potential therapeutic avenue in NSCLC
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