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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
191

Eduardo FP. Análise in vitro da fototerapia com lasers em baixa intensidade (660 nm e 780 nm) sobre a ação do vírus herpes tipo I em células epiteliais de macacos (Vero) [Tese de Doutorado]. São Paulo: Faculdade de Odontologia da USP; 2006. RESUMO / In vitro effect of phototherapy with low intensity laser (660 and 780 nm) on HSV-1 and monkey epithelial cells (Vero)

Fernanda de Paula Eduardo 09 May 2006 (has links)
A fototerapia com lasers em baixa intensidade de lesões de herpes simples tem sido demonstrada clinicamente ora prevenindo a formação de vesículas, ora cicatrizando rapidamente as lesões e até aumentando o espaço de tempo entre o aparecimento dessas manifestações recorrentes. No entanto, os mecanismos básicos de ação dos lasers nessas situações são desconhecidos. Dessa forma, o objetivo do trabalho foi realizar ensaios in vitro utilizando células epiteliais em cultivo e culturas do vírus HSV-1 para estudar a interferência do laser em baixa intensidade na infecção do HSV-1. Material e Métodos: Culturas de vírus HSV-1 e de células epiteliais de macaco (linhagem Vero) infectadas ou não infectadas, crescidas em déficit nutricional (2 % de soro fetal bovino - sfb) foram utilizadas. As irradiações foram realizadas com um laser de GaAlAs (660 e 780 nm, área focal de 3,6 mm2). Uma, duas e três irradiações com intervalos de 6 h foram realizadas. Os grupos experimentais foram: Controle: não-irradiadas; 660 nm/ 3 J/cm2 (28 s); 660 nm/ 5 J/cm2 (38 s); 780 nm/ 3 J/cm2 (19 s) e, 780 nm/ 5 J/cm2 (25 s). Os efeitos citopáticos do HSV-1 e a viabilidade celular de culturas irradiadas e controles foram analisadas em 4 condições: 1) irradiação das células epiteliais não infectadas; 2) células epiteliais irradiadas antes da infecção; 3) irradiação dos vírus antes da infecção; 4) irradiação das células previamente infectadas pelo HSV-1. A viabilidade celular foi obtida pelo teste da redução do MTT e os efeitos citopáticos por observação em microscopia de luz. Resultados: A viabilidade celular de culturas irradiadas crescidas em déficit nutricional, independentemente do número de irradiações, foi sempre significantemente menor que aquela de culturas não-irradiadas e crescidas nas condições ideais de concentração de sfb (10 %). A viabilidade celular de culturas não infectadas foi similar em todos os grupos. O número de irradiações influenciou o crescimento celular positiva e proporcionalmente ao número de irradiações, exceto para o grupo 660 nm/ 3 J/cm2. Nenhuma diferença nos efeitos citopáticos foi observada entre os grupos, independentemente do número de irradiações nas 3 condições do estudo. A viabilidade celular de todos os grupos não mudou nem pela irradiação das células nem do vírus antes da inoculação nas células. A viabilidade de células infectadas antes da irradiação foi significantemente maior que o controle quando 2 irradiações foram realizadas. Conclusão: Nas condições deste estudo a radiação laser em baixa intensidade é capaz de aumentar o crescimento de células Vero crescidas em déficit, no entanto, não o suficiente para atingir o crescimento característico dessas células crescidas nas suas condições ideais. O número de irradiações influencia o crescimento das células de forma positiva e proporcional ao número de irradiações, exceto para o parâmetro 660 nm/ 3 J/cm2. A radiação laser não altera nem a susceptibilidade das células à infecção, nem a virulência do HSV-1. No entanto, ela prolonga a viabilidade das células infectadas pelo HSV-1. Efeitos positivos da fototerapia que tem sido relatados clinicamente parecem ser devido a efeitos no hospedeiro não relacionados com a replicação viral nas células infectadas. / Purpose: The clinical effects attributed to phototherapy relative to Herpes simplex lesions have included prevention of lesion formation, speeding the healing of lesions, and decreasing the frequency of recurrent lesions. The mechanisms underlying these findings have not been established yet. The aim of this in vitro study was to analyze the effect of phototherapy on epithelial cells, on HSV-1, and on infected epithelial cells in culture. Material and Methods: Cultures of HSV-1 and infected or non-infected monkey epithelial cells (Vero cell line) grown in deficient media (2 % fetal bovine serum-fbs) were used. The laser irradiation was delivered using a GaAlAs laser (660 and 780 nm, focal spot of 3.6 mm2). One, two and three irradiations with 6 hourintervals were done. The experimental groups were: Control: non-irradiated; 660 nm/3 J/cm2 (28 sec); 660 nm/5 J/cm2 (38 sec); 780 nm/3 J/cm2 (19 sec), and 780 nm/5 J/cm2 (25 sec). The HSV-1 cytopatic effects and the cell viability of irradiated cultures and controls were analyzed in four different conditions: 1) irradiation of noninfected epithelial cells; 2) epithelial cells irradiated prior infection; 3) virus irradiated prior infection; and 4) irradiation of HSV-1 infected cells. The cell viability was assessed by the reduction of the MTT test and the cytopatic effects by the light microscopy observation. Results: The cell viability of irradiated cultures grown in nutritional deficit, independently of the irradiation numbers, was always significantly smaller than that of non-irradiated cultures grown at the ideal serum concentration condition (10 %). The cell viability of non-infected cells was similar amongst the groups. The number of irradiations influenced the cell growth positively and proportionally to the number of irradiations, except for the 660 nm/3J/cm2 group. Any variation in cytopatic effects was observed amongst the experimental groups, independently of the irradiation numbers at the 3 conditions analyzed. The cell viability of all experimental groups were not altered either by irradiation of the cells or of the virus prior infection. The viability of infected cells prior irradiation was significantly higher than that of non-irradiated cultures when 2 irradiations were done. Conclusion: The experimental conditions for this study demonstrate that the phototherapy is capable of enhancing the growth of Vero cells grown under nutritional deficit conditions, however, not enough to reach the characteristic cell growth of cells grown at the ideal serum concentration condition. The number of irradiations influences the cell growth positive and proportionally, except when the parameter 660 nm and 3 J/cm2 was used. The laser radiation does not change either the susceptibility of the Vero cell to the HSV-1 infection or the HSV-1 virulence; however, prolongs the cell viability of HSV-1 infected cells. Positive benefits of phototherapy that have been reported clinically would appear to be due to host effects unrelated to viral replication in infected cells.
192

Validering av Varicella Zoster virus och Herpes Simplex virus

Bajric, Amina January 2018 (has links)
Syftet med denna valideringsstudie är att värdera lämpligheten att överföra den manuella analysen av aktuell infektion av Varicella Zoster Virus (aVZV IgM) och Herpes Simplex Virus (aHSV IgM) med SIEMENS Enzygnost® till en av de automatiserade analysinstrumenten EUROIMMUN Analyzer I (ELISA) eller DiaSorin LIAISON® XL. Arbetet utfördes på Klinisk Mikrobiologi i Lund. Konsekutiva serumprover för VZV IgM (n=108) och för HSV IgM (n=116) från det vardagliga flödet analyserades, tillsammans med 10 PCR- eller serokonversion-konfirmerade positiva serumprover av primär infektion VZV och HSV samt 10 positiva för reaktiverad infektion av VZV och HSV. Utöver det användes 10 serumprover konfirmerade positiva för Cytomegalovirus (CMV) respektive 10 för Epstein-Barr Virus (EBV) för att testa korsreaktionen metoderna emellan. Resultatet från VZV-valideringen i Analyzer I samt LIAISON® XL gav en överensstämmelse på 93% respektive 94% av de konsekutiva proverna, 71% respektive 86% av de primärinfekterade proverna och 75% respektive 58% av de reaktiverade proverna, samt en korsreaktivitet (positiva och gränsvärden) på totalt 33% respektive 20% av proverna. Resultatet från HSV-valideringen i Analyzer I samt LIAISON® XL gav en överensstämmelse på 84% respektive 87% av de konsekutiva proverna, 82% respektive 18% av de primärinfekterade proverna och 40% respektive 10% av de reaktiverade proverna, samt en korsreaktivitet (positiva och gränsvärden) på totalt 67% respektive 47% av proverna. Enligt rekommendation efter utförandet av denna studie så bör analysen av HSV IgM uteslutas från båda automatiserade metoder medan VZV IgM bör kontrolleras något ytterligare i Analyzer I, med förhoppning om att denna metod kan vara känsligare. / The approach of this validation study is to evaluate the adequacy for transferring the manual analysis method of ongoing infection of Varicella Zoster Virus (aVZV IgM) and Herpes Simplex Virus (aHSV IgM) with SIEMENS Enzygnost® to one of the automated instruments EUROIMMUN Analyzer I (ELISA) or DiaSorin LIAISON® XL. The study was carried out at Clinical Microbiology in Lund. Consecutive serum samples for VZV IgM (n=108) and HSV IgM (n=116) from the daily local flow of tests were analyzed, along with 10 positive for primary infection of VZV and HSV, confirmed by PCR or seroconversion, and 10 with reactivated infection of VZV and HSV. Beyond those, 10 serum samples confirmed positive for Cytomegalovirus (CMV) respectively 10 for Epstein-Barr Virus (EBV) to test the cross-reaction between the three methods. The results from the validation of VZV in Analyzer I and LIAISON® XL gave an agreement of 93% and 94% respectively in the consecutive tests, 71% and 86% respectively in the primary infected tests and 75% and 58% respectively in the reactivated tests, and also a cross-reactivity (both positive and in between-values) at a total of 33% respectively 20% of the tests. The results from the validation of HSV in Analyzer I and LIAISON® XL gave an agreement of 84% and 87% respectively in the consecutive tests, 82% and 18% respectively in the primary infected tests and 40% and 10% respectively in the reactivated tests, and also a cross-reactivity (both positive and in between-values) at a total of 67% respectively 47% of the tests. According recommendations after the performance of this study, the analysis of HSV IgM should be excluded from both of the automated methods while VZV IgM should be controlled further in Analyzer I, with hopes that this new method could be more sensitive.
193

Host Nectin-1 Is Required for Efficient Chlamydia Trachomatis Serovar E Development

Hall, Jennifer V., Sun, Jingru, Slade, Jessica, Kintner, Jennifer, Bambino, Marissa, Whittimore, Judy, Schoborg, Robert V. 01 January 2014 (has links)
Interaction of Herpes Simplex Virus (HSV) glycoprotein D (gD) with the host cell surface during Chlamydia trachomatis/HSV co-infection stimulates chlamydiae to become persistent. During viral entry, gD interacts with one of 4 host co-receptors: HVEM (herpes virus entry mediator), nectin-1, nectin-2 and 3-O-sulfated heparan sulfate. HVEM and nectin-1 are high-affinity entry receptors for both HSV-1 and HSV-2. Nectin-2 mediates HSV-2 entry but is inactive for HSV-1, while 3-O-sulfated heparan sulfate facilitates HSV-1, but not HSV-2, entry. Western blot and RT-PCR analyses demonstrate that HeLa and HEC-1B cells express nectin-1 and nectin-2, but not HVEM. Because both HSV-1 and HSV-2 trigger persistence, these data suggest that nectin-1 is the most likely co-receptor involved. Co-infections with nectin-1 specific HSV-1 mutants stimulate chlamydial persistence, as evidenced by aberrant body (AB) formation and decreased production of elementary bodies (EBs). These data indicate that nectin-1 is involved in viral-induced chlamydial persistence. However, inhibition of signal transduction molecules associated with HSV attachment and entry does not rescue EB production during C. trachomatis/HSV-2 co-infection. HSV attachment also does not activate Cdc42 in HeLa cells, as would be expected with viral stimulated activation of nectin-1 signaling. Additionally, immunofluorescence assays confirm that HSV infection decreases nectin-1 expression. Together, these observations suggest that gD binding-induced loss of nectin-1 signaling negatively influences chlamydial growth. Chlamydial infection studies in nectin-1 knockdown (NKD) HeLa cell lines support this hypothesis. In NKD cells, chlamydial inclusions are smaller in size, contain ABs, and produce significantly fewer infectious EBs compared to C. trachomatis infection in control HeLa cells. Overall, the current study indicates that the actions of host molecule, nectin-1, are required for successful C. trachomatis development.
194

New Concepts in Herpes Simplex Virus Vaccine Development: Notes From the Battlefield

Dasgupta, Gargi, Chentoufi, Aziz A., Nesburn, Anthony B., Wechsler, Steven L., BenMohamed, Lbachir 01 August 2009 (has links)
The recent discovery that T cells recognize different sets of herpes simplex virus type 1 and type 2 epitopes from seropositive symptomatic and asymptomatic individuals might lead to a fundamental immunologic advance in vaccine development against herpes infection and diseases. The newly introduced needle-free mucosal (i.e., topical ocular and intravaginal) lipopeptide vaccines provide a novel strategy that might target ocular and genital herpes and possibly provide 'heterologous protection' from HIV-1. Indeed, mucosal self-adjuvanting lipopeptide vaccines are easy to manufacture, simple to characterize, extremely pure, cost-effective, highly immunogenic and safe. In this review, we bring together recent published and unpublished data that illuminates the status of epitope-based herpes vaccine development and present an overview of our recent approach to an 'asymptomatic epitope'-based lipopeptide vaccine.
195

The future of viral vectors for gene therapy

Ekstedt, Elias, Fryckstedt, Inna, Hyllander, Hanna, Jonsson, Josefin, Ring, Elin, Wærn, Felix January 2021 (has links)
Gene therapy is a fast growing technology that offers treatments for genetic diseases. The method is based on introducing genetic material into a patient to replace the disease-causing gene, using a vector. This report examines the potential of some viral vectors for gene therapy, to give Bio-Works Technologies a recommendation on what the future market demands. Oncolytic viruses, vaccines and gene editing are not treated in the report as a delimitation.  Viral vectors have different biological properties and require different purification methods, making them suitable for different applications in gene therapy. In the purification of the viruses it can be challenging to obtain a high purity and large-scale manufacturing. One major drawback with most purification methods is that they are not specific to just one virus, which leads to contaminants in the solution and lower purity. The viral vectors handled in the report are the adenovirus, adeno-associated virus, gammaretrovirus, lentivirus, alpharetrovirus, foamy virus, herpes simplex virus and baculovirus. These were chosen as they are relevant vectors for gene therapy and stay within the scope of the report. Lentiviral vectors (LVs) and adeno-associated viral vectors (AAVs) will dominate the gene therapy field in the coming years. This is based on the information that the use of AAVs and LVs in clinical trials have increased in recent years, while the other vectors mentioned above have slightly decreased or show no apparent change. However, challenges still remain in the purification processes. Ligands used in affinity chromatography for purification of AAVs are effective at removing most contaminants, but cannot distinguish between empty and loaded capsids, which can induce immune response when used clinically. This is the main challenge when purifying AAVs. The empty capsids can be removed with ion exchange chromatography, which results in higher purity but also lower recovery. There is no specific purifying method for LVs, therefore a lentivirus-specific affinity ligand, such as an antibody ligand, would be beneficial for the purification and manufacturing procedure.  In addition to AAVs and LVs, baculoviral vectors and foamy viral vectors show great potential in a long-term perspective but they only have been researched in preclinical studies. Moreover, herpes simplex viral vectors and adenoviral vectors show potential in cancer treatments or as vaccines rather than in augmentation gene therapy.
196

Nectin-1 is Degraded in <em>Chlamydia trachomatis</em>-Infected Genital Epithelial Cells and is Required for Herpes Simplex Virus Co-Infection-Induced <em>C. trachomatis</em> Persistence.

Sun, Jingru 09 May 2009 (has links) (PDF)
The obligate intracellular bacterium Chlamydia trachomatis is the most common bacterial STD agent in the US. This bacterium has a unique biphasic developmental cycle in which the infectious elementary body (EB) infects a host mucosal epithelial cell and differentiates into the replicative form (the reticulate body or RB) within a modified vacuole called an inclusion. The RB later divides and develops back into an EB and is released, perpetuating the infectious cycle. When developing chlamydiae are exposed to unfavorable environmental conditions, they deviate from the normal developmental cycle into a non-infectious but viable state termed persistence. Previous data from our laboratory indicate that i) during C. trachomatis/HSV co-infection, the chlamydiae become persistent and ii) HSV gD interaction with host cell surface is sufficient to induce this response. During viral entry, HSV gD interacts with one of four host co-receptors, one of which is the host adhesion molecule nectin-1. Interestingly, Western blotting demonstrated that nectin-1 is significantly decreased in C. trachomatis-infected HeLa cells. Additional studies indicated that active C. trachomatis replication is required for nectin-1 down-regulation and nectin-1 is likely down-regulated post-translationally. CPAF, a chlamydia-secreted protease, is responsible for degrading several host proteins. Both in vivo experiments using CPAF-specific chemical inhibitors and cell-free cleavage assays using recombinant CPAF indicate that nectin-1 is degraded by CPAF in C. trachomatis-infected cells. Further studies suggest that nectin-1 is the most likely candidate involved in triggering HSV-induced chlamydial persistence. Co-infection experiments using nectin-1-specific HSV-1 mutants suggest that nectin-1 is, indeed, required for persistence induction. Additional studies in single co-receptor-expressing CHO cells demonstrate that, despite the fact that HSV-1 enters both HVEM- and nectin-1-expressing cells, viral co-infection reduces chlamydial infectivity only in the CHO-nectin-1 cell line. These data confirm that HSV/nectin-1 interaction is sufficient for chlamydial persistence induction. Although nectin-1 ligation is known to activate Cdc42, pull-down assays indicate that Cdc42 is not activated in co-infected HeLa cells. Taken together, these data suggest that: i) HSV gD-nectin-1 binding activates a novel host epithelial cell pathway that restricts chlamydial development and ii) the chlamydiae may degrade nectin-1 to evade this inhibitory host response.
197

Investigation of the mechanisms of ozone-mediated viral inactivation

Ohmine, Seiga 10 July 2005 (has links) (PDF)
Previous studies have established that ozone-oxygen mixtures can be used to inactivate a variety of microorganisms including bacteria, fungi and viruses. Ozone is a potent reactive oxygen species (ROS) that rapidly decays into a variety of additional short half-life ROS which have been shown to cause oxidative damage to biological molecules. I hypothesize that controlled ozone exposure and the subsequent generation of additional ROS would reduce viral infectivity by lipid and/or protein peroxidation. A proprietary ozone-oxygen delivery system was used to inactivate a series of enveloped [herpes simplex virus type-1 strain McIntyre (HSV-1), vaccinia strain Elstree (VAC), vesicular stomatitis virus strain Indiana (VSV), and influenza A strain (H1N1) A/WS/33] and non-enveloped [human adenovirus type2 (Ad2)] viruses. Plaque reduction and suspension-infection viral antigen assays were used to determine inactivation kinetics. After ozonation, HSV-1 and VSV lost up to 6 log10 infectious particles in 15 min, while VAC and influenza A lost up to 5 log10 in 40 min and 30 min, respectively. In comparison, the non-enveloped Ad2 lost up to 5 log10 in 60 min. Increasing amounts of serum supplementation in the ozone treated virus suspensions slowed the rate of inactivation in both enveloped and non-enveloped viruses, suggesting the protective effect of serum against ozone. Lipid peroxidation was determined through a chromogenic assay for malondialdehyde (MDA), a byproduct of peroxidation events. MDA concentrations were inversely correlated with virus infectivity, as MDA concentrations elevated with virus exposure time to ozone. Transmission electron microscopy images of Ad2, HSV-1, VAC and VSV confirmed the drastic morphological changes that resulted from ozone treatment. The ROS-mediated attack compromised the integrity of the lipid envelopes and protein shells of the viruses. These data suggest that a wide range of viruses can be inactivated through use of an innovative ozone delivery system, thus validating my hypothesis.
198

The Effect of N-Methyl-N'-Nitro-N-Nitrosoguanidine on Herpes Simplex Virus Replication and Gene Expression

Arshoff, Larry Usher 12 1900 (has links)
Experiments were carried out to determine if pretreatment of cells with N-Methyl-N'-Nitro-N-Nitrosoguanidine (a potent alkylating agent known to induce DNA repair) would affect Herpes Simplex Virus Replication. The data demonstrated a 1.5 fold increase in virus yield, a 2 fold increase in HSV specific TK activity and no change in HSV specific DNA polymerase activity in MNNG treated cultures. The effects of MNNG treatment on virus replication and enzyme expression are discussed. / Thesis / Master of Science (MSc)
199

An Analysis of Heat Shock Protein Production in Human Retinal Pigment Epithelial Cells After Different Stress-Induced States

Krainz, Thomas Edward January 2018 (has links)
No description available.
200

Development of Oncolytic HSV-1 as an Anticancer Therapeutic for Extracranial Neural Tumors and Cancer Stem Cells

Mahller, Yonatan Y. January 2007 (has links)
No description available.

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