Effect of Intracrystalline Silanol Defects on the Diffusivity of Benzene in Silicalite Zeolite

[EN] Intracrystalline zeolite silanol defect groups (& EQUIV;SiOH) were modelled in silicalite (silica ZSM-5, MFI) using experimental data. We make a molecular dynamics study on the self-diffusivity of benzene in silicalite with defects. The simulations at three different loadings (1, 3 and 5 benzene per unit cell) and temperatures (298, 348 and 398 K) allow to calculate self-diffusivity, adsorption energy and the activation energy. The results show that benzene self-diffusivity in silicalite is increased by the presence of silanol defects. Previous experimental results support this claim.This work was supported by Generalitat Valenciana predoctoral fellowship GRISOLIAP/2019/084. We also thank Generalitat Valenciana for funding through PROMETEO/2021/077 project and CESGA for the use of computational facilities. Financial support by the Ministry of Science and Innovation (MICINN) of Spain through project CEX2021-001230-S (10.13039/501100011033) is gratefully acknowledged.Misturini, A.; Altundal, ÖF.; García-Aznar, P.; Kariminasab, S.; Sastre Navarro, GI. (2023). Effect of Intracrystalline Silanol Defects on the Diffusivity of Benzene in Silicalite Zeolite. Chemie Ingenieur Technik. 95(11):1768-1776. https://doi.org/10.1002/cite.20230000817681776951

Mandibular odontogenic myxoma : reconstructive considerations by means of the vascularized fibular free flap

The odontogenic myxoma is a rare entity located in mandible and upper maxilla. Due to its local aggressiveness, wide surgical excision is mandatory. Several surgical techniques have been described for the reconstruction of segmental mandibular defects. In comparison with other free flaps, the vascularized free fibular flap (VFFF) supports the longest amount of bone and, due to the nature of the vascular supply a complete freedom in location of the osteotomy is present. A precise mandibular arc can be performed following bone resection. We suggest the performance of the ?in situ? VFFF technique in order to recreate mandibular contour by means of several osteotomies, while the pedicle is still attached to the leg. Substantial decrease in surgical time is obtained. With the ?double-barrel? technique and subsequent osseointegrated implants, good results are obtained in the reconstruction of dentate patients without maxillary atrophy. We present two new cases of large odontogenic mandibular myxoma. Wide surgical excision by means of hemimandibulectomies and subsequent reconstruction with VFFF were performed

Endoscopically-assisted transoral approach for the treatment of subcondylar fractures of the mandible

Introduction: Treatment of subcondylar fractures of the mandible is one of the most controversial aspects in the field of maxillofacial traumatology. This controversy centers on the positive and negative aspects of open and closed approaches for the treatment of this kind of fractures. Open techniques lead to good reduction and osteosynthesis, but have a high risk of injury to the facial nerve and produce facial scars. Closed techniques (intermaxillary fixation) reduce all the above-mentioned risks but rarely produce correct anatomic reduction, and complications such as ankylosis, condylar necrosis and inhibition of mandibular growth, causing abnormal occlusion, may occur. Despite all the associated risks, closed techniques are currently the most popular treatment. Objectives: To introduce the endoscopically-assisted transoral approach for the treatment of subcondylar fractures, presenting three cases treated in our department. A description of the technique has been included as well as the clinical and radiographic results obtained. Material and Methods: The study is based in three patients with subcondylar fractures of the mandible who were treated by an endoscopically-assisted transoral approach. A description of the surgical technique is included. The results were assessed by postsurgical radiographic control (orthopantomography), maximum mouth opening, occlusion and pain. Results: Three reductions of subcondylar fractures with transoral endoscopically-assisted approach were undertaken. The follow-up period was 6 months. Postsurgical radiographic control showed good reduction of the fracture in all three cases. None of the patients showed any sign of temporomandibular dysfunction after 6 months. Conclusion: Endoscopic treatment by transoral approach combines the positive aspects of both conventional techniques: closed and open reduction; allowing anatomic reduction and a stable fixation leaving no visible facial scars and with a minimum risk of injury to the facial nerve

Complete-Proteome Mapping of Human Influenza A Adaptive Mutations: Implications for Human Transmissibility of Zoonotic Strains

BACKGROUND: There is widespread concern that H5N1 avian influenza A viruses will emerge as a pandemic threat, if they become capable of human-to-human (H2H) transmission. Avian strains lack this capability, which suggests that it requires important adaptive mutations. We performed a large-scale comparative analysis of proteins from avian and human strains, to produce a catalogue of mutations associated with H2H transmissibility, and to detect their presence in avian isolates. METHODOLOGY/PRINCIPAL FINDINGS: We constructed a dataset of influenza A protein sequences from 92,343 public database records. Human and avian sequence subsets were compared, using a method based on mutual information, to identify characteristic sites where human isolates present conserved mutations. The resulting catalogue comprises 68 characteristic sites in eight internal proteins. Subtype variability prevented the identification of adaptive mutations in the hemagglutinin and neuraminidase proteins. The high number of sites in the ribonucleoprotein complex suggests interdependence between mutations in multiple proteins. Characteristic sites are often clustered within known functional regions, suggesting their functional roles in cellular processes. By isolating and concatenating characteristic site residues, we defined adaptation signatures, which summarize the adaptive potential of specific isolates. Most adaptive mutations emerged within three decades after the 1918 pandemic, and have remained remarkably stable thereafter. Two lineages with stable internal protein constellations have circulated among humans without reassorting. On the contrary, H5N1 avian and swine viruses reassort frequently, causing both gains and losses of adaptive mutations. CONCLUSIONS: Human host adaptation appears to be complex and systemic, involving nearly all influenza proteins. Adaptation signatures suggest that the ability of H5N1 strains to infect humans is related to the presence of an unusually high number of adaptive mutations. However, these mutations appear unstable, suggesting low pandemic potential of H5N1 in its current form. In addition, adaptation signatures indicate that pandemic H1N1/09 strain possesses multiple human-transmissibility mutations, though not an unusually high number with respect to swine strains that infected humans in the past. Adaptation signatures provide a novel tool for identifying zoonotic strains with the potential to infect humans

Dengue virus co-opts UBR4 to degrade STAT2 and antagonize type I interferon signaling.

An estimated 50 million dengue virus (DENV) infections occur annually and more than forty percent of the human population is currently at risk of developing dengue fever (DF) or dengue hemorrhagic fever (DHF). Despite the prevalence and potential severity of DF and DHF, there are no approved vaccines or antiviral therapeutics available. An improved understanding of DENV immune evasion is pivotal for the rational development of anti-DENV therapeutics. Antagonism of type I interferon (IFN-I) signaling is a crucial mechanism of DENV immune evasion. DENV NS5 protein inhibits IFN-I signaling by mediating proteasome-dependent STAT2 degradation. Only proteolytically-processed NS5 can efficiently mediate STAT2 degradation, though both unprocessed and processed NS5 bind STAT2. Here we identify UBR4, a 600-kDa member of the N-recognin family, as an interacting partner of DENV NS5 that preferentially binds to processed NS5. Our results also demonstrate that DENV NS5 bridges STAT2 and UBR4. Furthermore, we show that UBR4 promotes DENV-mediated STAT2 degradation, and most importantly, that UBR4 is necessary for efficient viral replication in IFN-I competent cells. Our data underscore the importance of NS5-mediated STAT2 degradation in DENV replication and identify UBR4 as a host protein that is specifically exploited by DENV to inhibit IFN-I signaling via STAT2 degradation

Adjoint fermion zero-modes for SU(N) calorons

We derive analytic formulas for the zero-modes of the Dirac equation in the adjoint representation in the background field of Q=1 SU(N) calorons. Solutions with various boundary conditions are obtained, including the physically most relevant cases of periodic and antiperiodic ones. The latter are essential ingredients in a semiclassical treatment of finite temperature supersymmetric Yang-Mills theory. A detailed discussion of adjoint zero-modes in several other contexts is also presented.Comment: 40 latex pages and 5 eps figure

A Novel Paramyxovirus?

In public databases, we identified sequences reported as human genes expressed in kidney mesangial cells. The similarity of these genes to paramyxovirus matrix, fusion, and phosphoprotein genes suggests that they are derived from a novel paramyxovirus. These genes are sufficiently unique to suggest the existence of a novel paramyxovirus genus

Type I Interferon Imposes a TSG101/ISG15 Checkpoint at the Golgi for Glycoprotein Trafficking during Influenza Virus Infection

SummarySeveral enveloped viruses exploit host pathways, such as the cellular endosomal sorting complex required for transport (ESCRT) machinery, for their assembly and release. The influenza A virus (IAV) matrix protein binds to the ESCRT-I complex, although the involvement of early ESCRT proteins such as Tsg101 in IAV trafficking remain to be established. We find that Tsg101 can facilitate IAV trafficking, but this is effectively restricted by the interferon (IFN)-stimulated protein ISG15. Cytosol from type I IFN-treated cells abolished IAV hemagglutinin (HA) transport to the cell surface in infected semi-intact cells. This inhibition required Tsg101 and could be relieved with deISGylases. Tsg101 is itself ISGylated in IFN-treated cells. Upon infection, intact Tsg101-deficient cells obtained by CRISPR-Cas9 genome editing were defective in the surface display of HA and for infectious virion release. These data support the IFN-induced generation of a Tsg101- and ISG15-dependent checkpoint in the secretory pathway that compromises influenza virus release

Sinus elevation by in situ utilization of bone scrapers : technique and results

Objectives: The objective was to present a novel technique for antrostomy performed before sinus elevation in atrophic maxilla for subsequent implant placement. Material and methods: The study included 10 sinus elevations performed by the proposed technique in nine consecutive patients presenting with inadequate posterior maxillary height. The technique is described, calculating the antrostomy surface area, volume of bone tissue obtained and final height attained in each case. A total of 16 implants were placed. Results: All ten elevations were accomplished. Mean antrostomy surface area was 0.55 mm2 , mean bone volume obtained was 0.56 cm3 and mean height attained was 11.7 mm from a baseline mean height of 5.6 mm. Out of the 16 implants, 14 were inserted immediately after the elevation and 2 were inserted in a second step, after ossification; 93.7% of the implants were osseointegrated at 6 months after prosthesis placement. Conclusion: The use of bone scrapers to create antrostomy for sinus elevation is a simple and very safe procedure. It provides a variable amount of particulate bone graft that is easily handled and highly useful for packing the cavity that will elevate the sinus membrane