89 research outputs found
Sinonasal angioleiomyoma with adipocyte differentiation: clinicopathologic study of 2 cases and review of the literature
Angioleiomyoma (ALM) is a benign tumor of the skin and soft tissues composed of well differentiated smooth muscle cells arranged around and among many vascular channels. Few cases have been reported in the sinonasal region, where ALM may show a variable amount of mature adipose tissue that may make hard the distinction from angiomyolipoma.
We report here two cases that presented with a three- and six-month history of left nasal obstruction respectively. In both patients, clinical examination and imaging studies failed to reveal features of tuberous sclerosis complex and demonstrated a mass obliterating the nasal cavity arising from the inferior turbinate. Both masses were endoscopically excised. Pathologic analysis revealed highly vascularized tumors composed of well differentiated smooth muscle cells intermingled with a variable number of mature adipocytes. Immunostaining for melanocytic markers was negative. Based on these findings, both tumors were diagnosed as sinonasal-ALM with adipocytic differentiation.
These two cases indicate that both clinical data (i.e. absence of features of tuberous sclerosis complex) and immunohistochemistry (i.e. absence of melanocytic markers) are mandatory for the recognition of sinonasal-ALM with adipocytic differentiation. The term angiomyolipoma to identify these lesions is confusing and should be abandoned
Clinical recommendations for epistaxis management during the COVID-19 pandemic
Epistaxis is a common complaint in the general population, and its treatment is a common procedure in emergency departments. In the COVID-19 era, procedures involving airway management are a particular risk for health care workers due to the high virulence of the virus, the transmission through aerosol, and the risk of contagion from asymptomatic patients. In this article, we propose a simple memorandum of clinical recommendations to minimize the risk of operator infection deriving from epistaxis management. The correct use of personal protective equipment and strict compliance with the behavioral guidelines are essential to reduce the potential risk of infection. In particular, the use of filtering masks is strongly recommended since all patients, including those referring for epistaxis, should be treated as being COVID-19 positive in the emergency department. The safety of health care workers is essential not only to safeguard continuous patient care but also to limit virus transmission
Control of superluminal transit through a heterogeneous medium
We consider pulse propagation through a two component composite medium (metal
inclusions in a dielectric host) with or without cavity mirrors. We show that a
very thin slab of such a medium, under conditions of localized plasmon
resonance, can lead to significant superluminality with detectable levels of
transmitted pulse. A cavity containing the heterogeneous medium is shown to
lead to subluminal-to-superluminal transmission depending on the volume
fraction of the metal inclusions. The predictions of phase time calculations
are verified by explicit calculations of the transmitted pulse shapes. We also
demonstrate the independence of the phase time on system width and the volume
fraction under specific conditions.Comment: 21 Pages,5 Figures (Published in Journal of Modern Optics
Sporadic high-grade malignant peripheral nerve sheath tumor of the hypoglossal nerve
Malignant tumors of peripheral nerve sheaths (MPNSTs) are rare malignant soft tissue tumors arising either from a peripheral nerve or from a pre-existing benign nerve sheath tumor. They occur most often in the context of Neurofibromatosis type-1 (NF-1) and are characterized by poor prognosis and aggressive behavior with a high rate of recurrence and distant metastases. We describe a 50-year-old woman who presented with right neck swelling, progressive dysphagia and tongue paresis. Imaging analysis revealed a mass involving the right parapharyngeal space. The tumor was excissed through a transcervical approach. At surgery, the tumor was strictly adherent to the hypoglossal nerve. Pathologic evaluation of the mass revealed a high-grade MPNST. Based on the pathological diagnosis, a clinical work-up for NF-1 was performed but it resulted negative. Occurrence of sporadic high-grade MPNST in the parapharyngeal space is rare and development from the hypoglossal nerve exceptional. As far as we know, only in two cases, both with clinical features consistent with NF1, the tumor was reported to be arised from the hypoglossal nerve
Geometrical isotropy in perforated plates with subwavelength holes decorated with Archimedean patterns
The design and use of small apertures perforated in opaque plates to control the transmission of ultrasonic waves has been widely studied in recent years. The ultrasonic transmission response of brass plates perforated with Archimedean patterns of subwavelength hole arrays immersed in water is reported, both numerically and experimentally, in this work. It is shown that an increase in the geometrical isotropy of the elementary cells of the Archimedean patterns gives rise to a suppression of both minimum and maximum transmission corresponding to the destructive and constructive interferences, leading to uniformity within the angle-dependent transmitted sound power coefficient. The experimental results are in close agreement with the calculated ones. This property can be used to design ultrasonic devices such as filters and sensors.This work has been supported by the Spanish MICINN (MAT2010-16879) and Generalitat Valenciana (PROM-ETEOII/2014/026).GĂłmez Lozano, V.; Rubio Michavila, C.; Candelas Valiente, P.; Belmar Ibáñez, F.; Uris MartĂnez, A. (2015). Geometrical isotropy in perforated plates with subwavelength holes decorated with Archimedean patterns. EPL. 111(3):34002p1-34002p5. https://doi.org/10.1209/0295-5075/111/34002S34002p134002p5111
NH2-truncated human tau induces deregulated mitophagy in neurons by aberrant recruitment of Parkin and UCHL-1: implications in Alzheimer's disease.
Disarrangement in functions and quality control of mitochondria at synapses are early events in Alzheimer's disease (AD) pathobiology. We reported that a 20-22 kDa NH2-tau fragment mapping between 26 and 230 amino acids of the longest human tau isoform (aka NH2htau): (i) is detectable in cellular and animal AD models, as well in synaptic mitochondria and cerebrospinal fluids (CSF) from human AD subjects; (ii) is neurotoxic in primary hippocampal neurons; (iii) compromises the mitochondrial biology both directly, by inhibiting the ANT-1-dependent ADP/ATP exchange, and indirectly, by impairing their selective autophagic clearance (mitophagy). Here, we show that the extensive Parkin-dependent turnover of mitochondria occurring in NH2htau-expressing post-mitotic neurons plays a pro-death role and that UCHL-1, the cytosolic Ubiquitin-C-terminal hydrolase L1 which directs the physiological remodeling of synapses by controlling ubiquitin homeostasis, critically contributes to mitochondrial and synaptic failure in this in vitro AD model. Pharmacological or genetic suppression of improper mitophagy, either by inhibition of mitochondrial targeting to autophagosomes or by shRNA-mediated silencing of Parkin or UCHL-1 gene expression, restores synaptic and mitochondrial content providing partial but significant protection against the NH2htau-induced neuronal death. Moreover, in mitochondria from human AD synapses, the endogenous NH2htau is stably associated with Parkin and with UCHL-1. Taken together, our studies show a causative link between the excessive mitochondrial turnover and the NH2htau-induced in vitro neuronal death, suggesting that pathogenetic tau truncation may contribute to synaptic deterioration in AD by aberrant recruitment of Parkin and UCHL-1 to mitochondria making them more prone to detrimental autophagic clearance
p63 isoforms regulate metabolism of cancer stem cells
p63 is an important regulator of epithelial
development expressed in different variants containing (TA)
or lacking (\u394N) the N-terminal transactivation domain. The
different isoforms regulate stem-cell renewal and differentiation
as well as cell senescence. Several studies indicate
that p63 isoforms also play a role in cancer development;
however, very little is known about the role played by p63 in
regulating the cancer stem phenotype. Here we investigate the
cellular signals regulated by TAp63 and \u394Np63 in a model of
epithelial cancer stem cells. To this end, we used colon cancer
stem cells, overexpressing either TAp63 or \u394Np63 isoforms,
to carry out a proteomic study by chemical-labeling approach
coupled to network analysis. Our results indicate that p63 is
implicated in a wide range of biological processes, including metabolism. This was further investigated by a targeted strategy at
both protein and metabolite levels. The overall data show that TAp63 overexpressing cells are more glycolytic-active than \u394Np63
cells, indicating that the two isoforms may regulate the key steps of glycolysis in an opposite manner. The mass-spectrometry
proteomics data of the study have been deposited to the ProteomeXchange Consortium (http://proteomecentral.
proteomexchange.org) via the PRIDE partner repository with data set identifiers PXD000769 and PXD000768
Adaptive on-chip control of nano-optical fields with optoplasmonic vortex nanogates
A major challenge for plasmonics as an enabling technology for quantum
information processing is the realization of active spatio-temporal control of
light on the nanoscale. The use of phase-shaped pulses or beams enforces
specific requirements for on-chip integration and imposes strict design
limitations. We introduce here an alternative approach, which is based on
exploiting the strong sub-wavelength spatial phase modulation in the near-field
of resonantly-excited high-Q optical microcavities integrated into plasmonic
nanocircuits. Our theoretical analysis reveals the formation of areas of
circulating powerflow (optical vortices) in the near-fields of optical
microcavities, whose positions and mutual coupling can be controlled by tuning
the microcavities parameters and the excitation wavelength. We show that
optical powerflow though nanoscale plasmonic structures can be dynamically
molded by engineering interactions of microcavity-induced optical vortices with
noble-metal nanoparticles. The proposed strategy of re-configuring plasmonic
nanocircuits via locally-addressable photonic elements opens the way to develop
chip-integrated optoplasmonic switching architectures, which is crucial for
implementation of quantum information nanocircuits.Comment: 11 pages, 5 figure
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