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Facial nerve schwannomas (FNS) are rare benign tumors that can develop in any segment of the facial nerve. Patients often experience facial palsy and hearing loss after FNS removal or even before surgery. 1-3 Double-stage treatment is usually necessary for tumor resection and reconstruction of facial nerve function. 4,5 Video 1 describes the translabyrinthine approach for resection of the middle-posterior cranial fossa dumbbell FNS and end-to-side hypoglossal-facial nerve anastomosis in 1 stage. The case presented is of a 28-year-old female patient who suffered from right-side hearing loss for 1.5 years, right facial paralysis for 2 months (House-Brackmann grade V), and a right middle-posterior fossa dumbbell FNS extending from the right cerebellopontine angle area and internal auditory canal. Gross total resection of the tumor and hypoglossal-facial nerve end-to-side anastomosis were performed during the same procedure. Postoperative facial nerve function was House-Brackmann grade III at the 6-month follow-up. The patient experienced no postoperative complications. This case demonstrates the advantages of the translabyrinthine approach for middle-posterior fossa dumbbell FNS. This approach helps in achieving tumor resection and nerve anastomosis in 1 stage by avoiding multiple surgical intervention s for patients with hearing loss and impaired facial nerve function. The patient consented to surgery and the publication of her images. [ABSTRACT FROM AUTHOR]

This article concerns mainly on various ring properties of Morita contexts. Necessary and sufficient conditions are obtained for a general Morita context or a trivial Morita context or a generalized matrix ring over a ring to satisfy a certain ring property which is among being semilocal, semiperfect, left perfect, semiprimary, semipotent, potent, clean, strongly π-regular, semiregular, etc. Many known results on a formal triangular matrix ring are extended to a Morita context or a trivial Morita context. Some questions on this subject raised by Varadarajan in [22] are answered. [ABSTRACT FROM PUBLISHER]

The unit graph of a ring R, denoted G(R), is the simple graph defined on the elements of R with an edge between vertices x and y iff x + y is a unit of R. In this paper, we prove that the girth (G(R)) of the unit graph of an arbitrary ring R is 3, 4, 6 or ∞. We determine the rings R with R/J(R) semipotent and with (G(R)) = 6 or ∞, and classify the rings R with R/J(R) right self-injective and with (G(R)) = 3 or 4. [ABSTRACT FROM AUTHOR]

Let M be a right module over a ring R and let G be a group. The set MG of all formal finite sums of the form ∑ m g where m ∈ M becomes a right module over the group ring RG under addition and scalar multiplication similar to the addition and multiplication of a group ring. In this paper, we study basic properties of the RG-module MG, and characterize module properties of ( MG) in terms of properties of M and G. Particularly, we prove the module-theoretic versions of several well-known results on group rings, including Maschke's Theorem and the classical characterizations of right self-injective group rings and of von Neumann regular group rings. [ABSTRACT FROM AUTHOR]

Abstract: A well-known result of Wolfson [7] and Zelinsky [8] says that every linear transformation of a vector space V over a division ring D is a sum of two invertible linear transformations except when and . Indeed, many of these linear transformations satisfy a stronger property that they are sums of two commuting invertible linear transformations. The goal of this note is to prove that every linear transformation of a vector space V over a division ring D is a sum of two commuting invertible ones if and only if and . As a consequence, a sufficient and necessary condition is obtained for a semisimple module to have the property that every endomorphism is a sum of two commuting automorphisms. [Copyright &y& Elsevier]

Abstract: This paper concerns the formal matrix ring over a ring R defined by a central element s in R. Various basic properties of these rings are established; the isomorphism problem between these rings is addressed; some known results on the usual matrix rings are extended to the formal matrix rings; and the Cayley–Hamilton Theorem is proved for matrices in a formal matrix ring. [Copyright &y& Elsevier]

A module is defined to be an automorphism-invariant module if it is invariant under automorphisms of its injective hull. Quasi-injective modules and, more generally, pseudo-injective modules are all automorphism-invariant. Here we develop basic properties of these modules, and discuss when an automorphism-invariant module is quasi-injective or injective. Some known results on quasi-injective and pseudo-injective modules are extended. [ABSTRACT FROM AUTHOR]

Purpose: The herpes simplex virus type 1 tegument protein VP22 has the remarkable property of intercellular trafficking, thus making it a promising tool for improving gene transfer efficiency. Methods: To investigate whether the fusion of VP22 to the cytosine deaminase (CD) suicide gene could enhance the therapeutic efficiency of neural stem cells (NSCs) in the treatment for C6 glioma, the lentiviral vectors pHIV-VP-EGFP, pHIV-CD, and pHIV-VP-CD were constructed based on the pHIV-EGFP vector. After packaging, vectors were transduced into rat NSCs. Results: Fluorescence-activated cell sorting analysis revealed that the fusion of VP22-EGFP increased the expression rate of EGFP in NSCs compared with lenti-EGFP transduced cells. Under incubation with the prodrug 5-fluorocytosine (5-FC), the survival rates of C6 cells co-cultured with NSCs/VP-CD (NSCs transduced with lenti-VP-CD) decreased tremendously compared with those of C6 and NSCs/CD. Similar results were also observed in vivo; a significant reduction in tumor volumes in C6 glioma-bearing rats was observed in the NSCs/VP-CD therapy group when compared with other control groups. Conclusions: Our results reveal that VP22 increases the transduction efficiency of lentivirus into NSCs and enhances the therapeutic efficacy of CD-engineered rat NSCs in the treatment for C6 glioma, demonstrating that VP22 might be a useful tool for the gene therapy of engineered NSCs and providing a potential novel strategy for enhancing the effectiveness of gene therapy in other diseases. [ABSTRACT FROM AUTHOR]

For a polynomialwith zero constant term, a semiprime K-algebra R is called faithful f-free if every nonzero ideal of R does not satisfy f. We prove that a semiprime algebra has an essential ideal which is the direct sum of its largest faithful f-free ideal and its largest ideal satisfying the identity f. Here, faithful f-free algebras are characterized, and applications to some interesting differential identities are discussed. Especially with f = S2n(n ≥ 1), a description of semiprime rings is obtained in terms of faithful S2n-free rings and semiprime PI-rings of degree 2n. Semiprime PI-rings of degree 2n are realized through faithful S2n-rings. Finally, faithful S2n-rings are characterized. [ABSTRACT FROM PUBLISHER]

Abstract: Let K s(R) be the generalized matrix ring over a ring R with multiplier s. For a general local ring R and a central element s in the Jacobson radical of R, necessary and sufficient conditions are obtained for K s(R) to be a strongly clean ring. For a commutative local ring R and an arbitrary element s in R, criteria are obtained for a single element of K s(R) to be strongly clean and, respectively, for the ring K s(R) to be strongly clean. Specializing to s =1 yields some known results. New families of strongly clean rings are presented. [Copyright &y& Elsevier]