Pathogenesis of Human Papillomavirus – Immunological Responses to HPV Infection

Papillomavirus is an oncogenic virus which infects mucosal and cutaneous epithelia where it induces benign hyperproliferative lesions. Few studies have been conducted on the causative factors associated with the development of cancer. Infections by high-risk human papillomaviruses (HPVs) have been implicated as causative agents in a variety of cancers such as anogenital, and head and neck cancers. HPVs appear to have evolved mechanisms resulting in escape from host immune surveillance and delay of resolution of infection. The HPV E5 oncoprotein is one of the possible effectors that allows the virus to escape from host immune system through the downregulation of surface classical major histocompatibility complex class I (MHC I) and not the nonclassical MHC I. Lack of classical MHC I in infected cells expressing E5 would allow evasion of cytotoxic T lymphocytes (CTLs) killing and thus establishment and persistence of viral infection

The Eccentric Connectivity Polynomial of some Graph Operations

The eccentric connectivity index of a graph G, ξ^C, was proposed by Sharma, Goswami and Madan. It is defined as ξ^C(G) = ∑ u ∈ V(G) degG(u)εG(u), where degG(u) denotes the degree of the vertex x in G and εG(u) = Max{d(u, x) | x ∈ V (G)}. The eccentric connectivity polynomial is a polynomial version of this topological index. In this paper, exact formulas for the eccentric connectivity polynomial of Cartesian product, symmetric difference, disjunction and join of graphs are presented.* The work of this author was supported in part by a grant from IPM (No. 89050111)

The Wiener, Eccentric Connectivity and Zagreb Indices of the Hierarchical Product of Graphs

Let G1 = (V1, E1) and G2 = (V2, E2) be two graphs having a distinguished or root vertex, labeled 0. The hierarchical product G2 ⊓ G1 of G2 and G1 is a graph with vertex set V2 × V1. Two vertices y2y1 and x2x1 are adjacent if and only if y1x1 ∈ E1 and y2 = x2; or y2x2 ∈ E2 and y1 = x1 = 0. In this paper, the Wiener, eccentric connectivity and Zagreb indices of this new operation of graphs are computed. As an application, these topological indices for a class of alkanes are computed. ACM Computing Classification System (1998): G.2.2, G.2.3.The research of this paper is partially supported by the University of Kashan under grant no 159020/12

Some remarks on Laplacian eigenvalues and Laplacian energy of graphs

Suppose $mu_1$, $mu_2$, ... , $mu_n$ are Laplacian eigenvalues of a graph $G$. The Laplacian energy of $G$ is defined as $LE(G) = sum_{i=1}^n|mu_i - 2m/n|$. In this paper, some new bounds for the Laplacian eigenvalues and Laplacian energy of some special types of the subgraphs of $K_n$ are presented

Mutational Analysis of the Transforming Protein E8 of Bovine Papillomavirus Type-4 (BPV-4)

The transforming genes of bovine papillomavirus type 4 (BPV-4) are encoded by the E7 and E8 open reading frames (ORFs). E7 is the transforming gene of BPV-4, in that, in co-operation with activated ras, it induces morphological transformation of primary bovine fibroblasts (PalF) in the absence of other viral genes, but the acquisition of anchorage independent growth requires the additional presence of E8. The BPV-4 E8 is a small transforming protein localized to cellular membrane. It consists of two domains: a very hydro'phobic region encompassing the first 30 amino acids of the protein, and a second region of mainly hydrophilic amino acids comprising the C terminal 12 residues. The results in this thesis demonstrated that in addition to the ability of E8 to grow independently of anchorage, PalF cells expressing E8 lose gap junction intercellular communication (GJIC), can grow in low serum, and are not contact inhibited. E8 also transactivates the cyclin A promoter in PalF cells. Mutant forms of E8 were generated to establish if the transforming functions of the protein could be segregated and therefore to define its functional domains. Mutations were introduced both in the hydrophobic domain and in the hydrophilic C-terminal tail, and chimeras with BPV-1 E5 were constructed. Cells expressing either E8 wild type or its mutants were analysed for their ability to: morphological transformation, anchorage independent growth, focus formation, cell population growth in low serum, tumorigenicity in nude mice, trans-activation of the cyclin A promoter, binding to ductin and down regulation of GJIC. The analysis of E8 mutants and chimeras constructed with BPV-1 E5 show that the multiple transforming function of E8 can be segregated and that both the hydrophobic domain and the hydrophilic C-terminal tail of E8 are critical for its functions and for the transactivation of the cyclin A promoter. These results support the hypothesis that the different aspects of cellular transformation produced by E8 might be due to interaction with different cellular targets. The observation from the analysis of the transformation parameters of E8 and BPV-1 E5 expressing cells suggest that E8 acts differently from E5. This study also demonstrates that the separate domains of E5 and E8 are not functionally interchangeable. The short term co-transfection analysis of E8 mutants suggest that substitution of alanine with proline, which is expected to alter the conformation of the hydrophobic domain, may have an effect on cell transformation. Also the short-term co-transfection experiments of E8 mutants in the putative casein kinase II site support the possibility that BPV-4 E8 might be phosphorylated by CKII and that this phosphorylation could have an effect on the biological activities of this protein

Head Trauma as a Precipitating Factor for Late-onset Leigh Syndrome: a Case Report

Leigh syndrome is a severe progressive neurodegenerative disorder with different clinical presentationsthat usually becomes apparent in the first year of life and rarely in late childhood and elderly years. It is causedby failure of mitochondrial respiratory chain and often results in regression of both mental and motor skills and might even lead to death. In some of the inherited neurodegenerative diseases like Alexander disease, head trauma is reported as a trigger for onset of the disease. We present a late onset Leigh syndrome in a 14-year-old girl whose symptoms were initiating following head trauma

On the Szeged and the Laplacian Szeged spectrum of a graph

AbstractFor a given graph G its Szeged weighting is defined by w(e)=nu(e)nv(e), where e=uv is an edge of G,nu(e) is the number of vertices of G closer to u than to v, and nv(e) is defined analogously. The adjacency matrix of a graph weighted in this way is called its Szeged matrix. In this paper we determine the spectra of Szeged matrices and their Laplacians for several families of graphs. We also present sharp upper and lower bounds on the eigenvalues of Szeged matrices of graphs

Assessment of Clindamycin and Erythromycin Resistance, and Inducible Clindamycin Resistance in Streptococcus Group B Isolated from Urinary Samples of Outpatient Women in Tehran

Background: Streptococcus group B (GBS) or Streptococcus agalactiae is typically associated with neonatal disease and infection in pregnant women. Mortality of GBS sepsis in neonates is over 50% and is particularly high in preterm infants. GBS also causes invasive infection in pregnant and non-pregnant women including urinary tract infection (UTI). Penicillin-derived antibiotics remained as choice drugs for treatment of GBS infection; however, Erythromycin and Clindamycin are useful in cases of allergic to Penicillin. The aim of this study was to investigate the resistance to Erythromycin and Clindamycin, especially inducible Clindamycin resistance, in GBS isolated from urinary samples of women who attended medical offices in Tehran, Iran.Materials and Methods: This study was conducted on 5000 urine samples from Jan. 2011 to Oct. 2012 that 104 GBS were isolated. The isolates were identified as GBS using laboratory criteria. Antimicrobial susceptibility test was done by Erythromycin disk 15µg and Clindamycin disk 2µg for observation inducible resistant D-zone test by double-disk diffusion method with Erythromycin and adjacent Clindamycin.Results: Among the 5000 urine samples 104 (2.08%) were Beta hemolytic GBS. Of the 104 isolated GBS, 22 (21.2%) were resistance, 24 (23%) were intermediate, and 58 (55.8%) were susceptible to Erythromycin; however, 24 (23%) were resistance, 5 (4.8%) were intermediate, and 75 (72.2%) were susceptible to Clindamycin. Of the 22 Erythromycin-resistant isolates, 10 (9.5% in total GBS isolated) displayed the D zone; it means they have inducible Erythromycin resistant to Clindamycin.Conclusion: Various studies in other countries report lower rates of inducible Clindamycin resistance; it indicates the use of more macrolides in the treatment of UTI

Eusociality unveiled: discovery and documentation of two new eusocial shrimp species (Caridea: Alpheidae) from the Western Indian Ocean

Abstract The alpheid snapping shrimp genus Synalpheus Spence Bate, 1888, is a prominent component of arthropod diversity found in coral reefs. Notably, Synalpheus is the only genus of marine organisms known to exhibit eusocial behavior. Although eusociality has evolved at least four times independently in Synalpheus, all described eusocial species are from the West Atlantic, with only a single study documenting possibly eusocial species from Indonesia. In 2008, during an expedition to Madagascar organized by the Florida Museum of Natural History (FLMNH), a diverse array of sponge-dwelling species was collected, including two species of Synalpheus exhibiting colonial behavior. Through detailed examination of these specimens, we have confirmed that these two species are eusocial and represent new eusocial species of Synalpheus outside of the West Atlantic. Consequently, we provide the first official documentation of eusocial species from the Western Indian Ocean and present their taxonomic descriptions and their phylogenetic relationships with other species of the genus in this study