212 research outputs found
A literature review on surgery for cervical vagal schwannomas
Cervical vagal schwannoma is a benign, slow-growing mass, often asymptomatic, with a very low lifetime risk of malignant transformation in general population, but diagnosis is still a challenge. Surgical resection is the treatment of choice even if its close relationship with nerve fibres, from which it arises, threats vagal nerve preservation. We present a case report and a systematic review of literature. All studies on surgical resection of cervical vagal schwannoma have been reviewed. Papers matching the inclusion criteria (topic on surgical removal of cervical vagal schwannoma, English language, full text available) were selected. Fifty-three patients with vagal neck schwannoma submitted to surgery were identified among 22 studies selected. Female/male ratio was 1.5 and median age 44 years. Median diameter was 5 cm (range 2 to 10). Most schwannoma were asymptomatic (68.2%) and received an intracapsular excision (64.9%). Postoperative symptoms were reported in 22.6% of patients. Cervical vagal schwannoma is a benign pathology requiring surgical excision, but frequently postoperative complications can affect patients lifelong, so, surgical indications should be based carefully on the balance between risks and benefits
A Molecular Platinum Cluster Junction: A Single-Molecule Switch
We present a theoretical study of the electronic transport through
single-molecule junctions incorporating a Pt6 metal cluster bound within an
organic framework. We show that the insertion of this molecule between a pair
of electrodes leads to a fully atomically engineered nano-metallic device with
high conductance at the Fermi level and two sequential high on/off switching
states. The origin of this property can be traced back to the existence of a
HOMO which consists of two degenerate and asymmetric orbitals, lying close in
energy to the Fermi level of the metallic leads. Their degeneracy is broken
when the molecule is contacted to the leads, giving rise to two resonances
which become pinned close to the Fermi level and display destructive
interference.Comment: 4 pages, 4 figures. Reprinted (adapted) with permission from J. Am.
Chem. Soc., 2013, 135 (6), 2052. Copyright 2013 American Chemical Societ
Sour Taste Responses in Mice Lacking PKD Channels
The polycystic kidney disease-like ion channel PKD2L1 and its associated
partner PKD1L3 are potential candidates for sour taste receptors. PKD2L1 is
expressed in type III taste cells that respond to sour stimuli and genetic
elimination of cells expressing PKD2L1 substantially reduces chorda tympani
nerve responses to sour taste stimuli. However, the contribution of PKD2L1
and PKD1L3 to sour taste responses remains unclear.We made mice lacking PKD2L1 and/or PKD1L3 gene and investigated whole nerve
responses to taste stimuli in the chorda tympani or the glossopharyngeal
nerve and taste responses in type III taste cells. In mice lacking PKD2L1
gene, chorda tympani nerve responses to sour, but not sweet, salty, bitter,
and umami tastants were reduced by 25–45% compared with those
in wild type mice. In contrast, chorda tympani nerve responses in PKD1L3
knock-out mice and glossopharyngeal nerve responses in single- and
double-knock-out mice were similar to those in wild type mice. Sour taste
responses of type III fungiform taste cells (GAD67-expressing taste cells)
were also reduced by 25–45% by elimination of PKD2L1.These findings suggest that PKD2L1 partly contributes to sour taste responses
in mice and that receptors other than PKDs would be involved in sour
detection
Piezo1-pannexin-1-P2X3 axis in odontoblasts and neurons mediates sensory transduction in dentinal sensitivity
©2022 Ohyama, Ouchi, Kimura, Kurashima, Yasumatsu, Nishida, Hitomi, Ubaidus, Kuroda, Ito, Takano, Ono, Mizoguchi, Katakura and Shibukawa. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms
A New Species of Saphonecrus (Hymenoptera, Cynipoidea) Associated With Plant Galls on Castanopsis (Fagaceae) in China
A new cynipid species, Saphonecrus hupingshanensis Liu, Yang, et Zhu, sp. nov. (Hymenoptera: Cynipidae: Synergini), is described from China. This is the first species of the inquilinous tribe Synergini ever known to have an association with chinquapins (Fagaceae: Castanopsis). The biology and implication to species diversity of Cynipidae in eastern and southeast Asia are discussed
Maspin is a tumour suppressor that inhibits breast cancer tumour metastasis in vivo
Maspin is a member of the serpin family of serine proteases and functions as a tumour suppressor. A study using a new syngeneic mouse model for breast cancer suggests that maspin can inhibit metastasis in vivo
The associated expression of Maspin and Bax proteins as a potential prognostic factor in intrahepatic cholangiocarcinoma
BACKGROUND: Maspin, a member of the serpin family, is a suppressor of tumor growth, an inhibitor of angiogenesis and an inducer of apoptosis. Maspin induces apoptosis by increasing Bax, a member of the Bcl-2 family of apoptosis-regulating proteins. In this exploratory study, we investigated the associated expression of Maspin and Bax proteins as a potential prognostic factor in intrahepatic cholangiocarcinoma (IHCCA). METHODS: Twenty-two paraffin-embedded samples were analyzed by immunohistochemical methods using Maspin, Bax and CD34 antibodies. Maspin was scored semiquantitatively (HSCORE). Apoptosis was assessed using an antibody against cleaved caspase-3. RESULTS: The strong relationship observed between the expression of Maspin and Bax, indicates that Bax is likely to be the key effector of Maspin-mediated induction of apoptosis as indicated by the activation of cleaved caspase-3. We categorized Maspin HSCORE by calculating the optimal cutpoint. A Maspin HSCORE above the cutpoint was inversely related with tumor dimension, depth of tumor and vascular invasion. Uni/multivariate analysis suggests that a Maspin HSCORE below the cutpoint significantly worsens the patients' prognosis. Tumors with Maspin HSCORE below the cutpoint had a shorter survival (11+/-5 months) than did patients with Maspin HSCORE above the cutpoint (27+/-4 months), whereas Kaplan-Meier analysis and logrank test showed no significant difference in overall survival between the patients. CONCLUSION: The associated expression of Maspin and Bax might delay tumor progression in IHCCA. Maspin above the cutpoint might counteract tumor development by increasing cell apoptosis, and by decreasing tumor mass and cell invasion. The combined expression of Maspin and Bax appears to influence the susceptibility of tumor cholangiocytes to apoptosis and thus may be involved in delaying IHCCA progression
Bimetallic Ag-Pt Sub-nanometer Supported Clusters as Highly Efficient and Robust Oxidation Catalysts
A combined experimental and theoretical investigation of Ag-Pt sub-nanometer clusters as heterogeneous catalysts in the CO→CO_2 reaction (COox) is presented. Ag_9Pt_2 and Ag_9Pt_3 clusters are size-selected in the gas phase, deposited on an ultrathin amorphous alumina support, and tested as catalysts experimentally under realistic conditions and by first-principles simulations at realistic coverage. In situ GISAXS/TPRx demonstrates that the clusters do not sinter or deactivate even after prolonged exposure to reactants at high temperature, and present comparable, extremely high COox catalytic efficiency. Such high activity and stability are ascribed to a synergic role of Ag and Pt in ultranano-aggregates, in which Pt anchors the clusters to the support and binds and activates two CO molecules, while Ag binds and activates O_2, and Ag/Pt surface proximity disfavors poisoning by CO or oxidized species
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