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1.
J Cosmet Laser Ther ; 26(1-4): 86-88, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38914106

RESUMO

Contemporary approaches for facial rejuvenation encompass the utilization of both ablative and nonablative laser techniques. Extensive research has elucidated the adverse consequences associated with ablative laser treatment, such as the emergence of infectious, follicular, scarring, and pigmentary alterations. Nonablative fractional lasers exhibit commendable cosmetic outcomes, characterized by a diminished incidence of complications owing to their photomechanical mechanisms, in contrast to ablative laser modalities. Nonetheless, it is imperative to acknowledge that untoward effects may still manifest. In this report, we present two cases of herpes simplex virus (HSV) reactivation subsequent to nonablative fractional resurfacing. Timely identification and the appropriate administration of antiviral agents are important, which serve as imperative measures to mitigate the long-term consequences that may arise in the event of complications.


Assuntos
Envelhecimento da Pele , Humanos , Feminino , Envelhecimento da Pele/efeitos da radiação , Pessoa de Meia-Idade , Terapia com Luz de Baixa Intensidade/métodos , Terapia com Luz de Baixa Intensidade/efeitos adversos , Herpes Simples/etiologia , Ativação Viral/efeitos da radiação , Simplexvirus , Antivirais/uso terapêutico , Rejuvenescimento , Técnicas Cosméticas/efeitos adversos , Técnicas Cosméticas/instrumentação , Face , Terapia a Laser/efeitos adversos , Terapia a Laser/métodos
2.
J Oncol Pharm Pract ; 27(5): 1296-1301, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33054690

RESUMO

INTRODUCTION: Hepatitis B virus (HBV) infection remains a global public health threat, with approximately 257 million people suffering from chronic HBV infection worldwide in 2015. HBV reactivation is a known complication of immunosuppressive therapy in people suffering with chronic HBV. Medications commonly associated with HBV reactivation include B-cell depleting agents and anthracycline derivatives. There have been very few documented cases of chemoradiation inducing HBV reactivation among scientific literature. CASE REPORT: A 44-year-old woman with chronic HBV infection and [FIGO] stage IIIB cervical cancer developed marked transaminitis and increased HBV viral load after receiving treatment with three doses of cisplatin and one dose of carboplatin with concurrent radiation for cervical cancer.Management and outcome: The patient was admitted for acute liver failure and quickly developed encephalopathy, with treatment complicated by coagulopathy, hypoglycemia, and metabolic acidosis. The patient remained unresponsive to maximal therapeutic efforts and was mechanically ventilated for airway protection. She subsequently died after experiencing ventricular tachycardia followed by asystole. DISCUSSION: There are currently no standardized guidelines for the screening of HBV infection or prophylaxis treatment algorithm for patients undergoing chemoradiation. When initiating treatment with immunosuppressive therapy, it is important to screen all patients for chronic HBV infection and to work with an interdisciplinary team of oncologists, hepatologists, and pharmacists to initiate prophylactic antiviral therapy and closely monitor to minimize the risk of HBV reactivation.


Assuntos
Hepatite B Crônica/virologia , Neoplasias do Colo do Útero/terapia , Adulto , Antivirais/uso terapêutico , Evolução Fatal , Feminino , Humanos , Ativação Viral/efeitos dos fármacos , Ativação Viral/efeitos da radiação
3.
J Cosmet Laser Ther ; 21(3): 145-146, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30019972

RESUMO

Fractional photothermolysis was initially introduced by Manstein in 2004 .Fractional CO2 laser technology introduced has allowed physicians to obtain good cosmetic results with a lower rate of complications than non-fractionated ablative laser treatment. However, adverse effects may still occur.Reported cases of HSV infection after fractional photothermolysis are rare. A 48-year-old woman with Fitzpatrick skin type III presented with a scar in her perioral area desiring esthetic improvement of her burn scar. She didn't have a history of recurrent herpes simplex virus (HSV) infection periorally. A fractionated resurfacing laser Quadralase (Candela) was used to treat her perioral burn scar. Two sessions were performed with a month interval. Five days after the second session of laser therapy even after she took antiviral prophylaxis based on valacyclovir 500mg twice daily 24 hours before the laser session and 3 days after, she presented with a rash on the perioral area preceded by pain. Correlation of the history and the clinical presentation was consistent with HSV reactivation. Treatment was initiated with acyclovir 10mg/kg/8h administered intravenously for 10 days with a clearing of her vesicular eruption. Fractional CO2 laser is a very safe procedure when used with accepted parameters. Early recognition, close monitoring and careful wound care will prevent long term sequelae when complications occur.


Assuntos
Queimaduras/complicações , Cicatriz/radioterapia , Herpes Simples/etiologia , Lasers de Gás/efeitos adversos , Terapia com Luz de Baixa Intensidade/efeitos adversos , Simplexvirus/efeitos da radiação , Ativação Viral/efeitos da radiação , Aciclovir/administração & dosagem , Aciclovir/uso terapêutico , Administração Intravenosa , Antibioticoprofilaxia , Antivirais/administração & dosagem , Antivirais/uso terapêutico , Cicatriz/etiologia , Fracionamento da Dose de Radiação , Feminino , Seguimentos , Herpes Simples/tratamento farmacológico , Humanos , Lasers de Gás/uso terapêutico , Pessoa de Meia-Idade , Boca/patologia , Simplexvirus/fisiologia , Resultado do Tratamento
4.
Int J Mol Sci ; 19(10)2018 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-30274169

RESUMO

Among the many stressors astronauts are exposed to during spaceflight, cosmic radiation may lead to various serious health effects. Specifically, space radiation may contribute to decreased immunity, which has been documented in astronauts during short- and long-duration missions, as evidenced by several changes in cellular immunity and plasma cytokine levels. Reactivation of latent herpes viruses, either directly from radiation of latently infected cells and/or from perturbation of the immune system, may result in disease in astronauts. Epstein‒Barr virus (EBV) is one of the eight human herpes viruses known to infect more than 90% of human adults and persists for the life of the host without normally causing adverse effects. Reactivation of several latent viruses in astronauts is well documented, although the mechanism of reactivation is not well understood. We studied the effect of four different types of radiation, (1) 137Cs gamma rays, (2) 150-MeV protons, (3) 600 MeV/n carbon ions, and (4) 600 MeV/n iron ions on the activation of lytic gene transcription and of reactivation of EBV in a latently infected cell line (Akata) at doses of 0.1, 0.5, 1.0, and 2.0 Gy. The data showed that for all doses used in this study, lytic gene transcription was induced and median viral loads were significantly higher for all types of radiation than in corresponding control samples, with the increases detected as early as four days post-exposure and generally tapering off at later time points. The viability and size of EBV-infected Akata cells were highly variable and exhibited approximately the same trend in time for all radiation types at 0.1, 0.5, 1.0, and 2.0 Gy. This work shows that reactivation of viruses can occur due to the effect of different types of radiation on latently infected cells in the absence of changes or cytokines produced in the immune system. In general, gamma rays are more effective than protons, carbon ions, and iron ions in inducing latent virus reactivation, though these high-energy particles did induce more sustained and later reactivation of EBV lytic gene transcription. These findings also challenge the common relative biological effectiveness concept that is often used in radiobiology for other end points.


Assuntos
Carbono/química , Raios gama , Herpesvirus Humano 4/fisiologia , Herpesvirus Humano 4/efeitos da radiação , Ferro/química , Prótons , Ativação Viral/efeitos da radiação , Latência Viral/efeitos da radiação , Linhagem Celular , Tamanho Celular/efeitos da radiação , Sobrevivência Celular/efeitos da radiação , Humanos , Fótons , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Carga Viral/efeitos da radiação
5.
Int J Cancer ; 141(9): 1722-1729, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28571118

RESUMO

Epstein-Barr virus (EBV) is an important cancer causing virus. Cancer associated with EBV account for approximately 1.5% of all cancers, and represent 1.8% of all cancer deaths worldwide. EBV reactivation plays an important role in the development of EBV-related diseases and is closely related with patients' survival and clinical stages of EBV-related cancers. The therapy regarding to EBV-related cancers is very urgent, especially in endemic areas. Generating oxidative stress is a critical mechanism by which host cells defend against infection by virus. In addition, ROS-mediated oxidative stress plays a significant but paradoxical role acting as a "double-edged sword" to regulate cellular response to radiation, which is the main therapy strategy for EBV-related cancers, especially nasopharyngeal carcinoma. Therefore, in this review we primarily discuss the possible interplay among the oxidative stress, EBV lytic reactivation and radioresistance. Understanding the role of oxidative stress in EBV lytic reactivation and radioresistance will assist in the development of effective strategies for prevention and treatment of EBV-related cancers.


Assuntos
Carcinoma/genética , Infecções por Vírus Epstein-Barr/genética , Neoplasias Nasofaríngeas/genética , Estresse Oxidativo/genética , Tolerância a Radiação/genética , Carcinoma/patologia , Carcinoma/radioterapia , Carcinoma/virologia , Infecções por Vírus Epstein-Barr/patologia , Infecções por Vírus Epstein-Barr/radioterapia , Infecções por Vírus Epstein-Barr/virologia , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/patogenicidade , Herpesvirus Humano 4/efeitos da radiação , Interações Hospedeiro-Patógeno , Humanos , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/radioterapia , Neoplasias Nasofaríngeas/virologia , Estresse Oxidativo/efeitos da radiação , Ativação Viral/genética , Ativação Viral/efeitos da radiação
6.
Microb Pathog ; 109: 4-7, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28506884

RESUMO

Studies aimed at investigating factors and mechanism of induction of prophages, a major pathogenesis factor of Shiga toxin-producing Escherichia coli (STEC), are considered important to develop an effective treatment for STEC infections. In this study, we demonstrated the synergistic effect of the rotating magnetic field (RMF) of induction B = 34 mT and frequency ƒ = 50 Hz at a constant temperature of 37 °C and mitomycin C (MMC), that resulted in a higher level of induction of stx-carrying lambdoid Stx prophages. This is a first report on the induction of lambdoid Stx prophages in response to the enhancing effect of popular inductor (mitomycin C) under the influence of RMF.


Assuntos
Campos Magnéticos , Prófagos/efeitos da radiação , Toxina Shiga/efeitos da radiação , Ativação Viral/efeitos da radiação , Mitomicina , Prófagos/efeitos dos fármacos , Prófagos/crescimento & desenvolvimento , Ondas de Rádio , Toxina Shiga/genética , Toxina Shiga I/genética , Toxina Shiga I/efeitos da radiação , Toxina Shiga II/genética , Toxina Shiga II/efeitos da radiação , Escherichia coli Shiga Toxigênica , Ativação Viral/efeitos dos fármacos
7.
Clin Exp Immunol ; 181(3): 491-510, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25902927

RESUMO

In this study we examined the effects of non-myeloablative total body irradiation (TBI) in combination with immunosuppressive chemotherapy on immune homeostasis in rhesus macaques. Our results show that the administration of cyclosporin A or tacrolimus without radiotherapy did not result in lymphopenia. The addition of TBI to the regimen resulted in lymphopenia as well as alterations in the memory/naive ratio following reconstitution of lymphocyte populations. Dendritic cell (DC) numbers in whole blood were largely unaffected, while the monocyte population was altered by immunosuppressive treatment. Irradiation also resulted in increased levels of circulating cytokines and chemokines that correlated with T cell proliferative bursts and with the shift towards memory T cells. We also report that anti-thymocyte globulin (ATG) treatment and CD3 immunotoxin administration resulted in a selective and rapid depletion of naive CD4 and CD8 T cells and increased frequency of memory T cells. We also examined the impact of these treatments on reactivation of latent simian varicella virus (SVV) infection as a model of varicella zoster virus (VZV) infection of humans. None of the treatments resulted in overt SVV reactivation; however, select animals had transient increases in SVV-specific T cell responses following immunosuppression, suggestive of subclinical reactivation. Overall, we provide detailed observations into immune modulation by TBI and chemotherapeutic agents in rhesus macaques, an important research model of human disease.


Assuntos
Sistema Imunitário/efeitos dos fármacos , Sistema Imunitário/efeitos da radiação , Imunossupressores/farmacologia , Irradiação Corporal Total/métodos , Animais , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Ciclosporina/farmacologia , Citocinas/sangue , Citocinas/metabolismo , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Células Dendríticas/efeitos da radiação , Ensaio de Imunoadsorção Enzimática , Feminino , Homeostase/efeitos dos fármacos , Homeostase/efeitos da radiação , Sistema Imunitário/citologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Leucócitos/efeitos dos fármacos , Leucócitos/metabolismo , Leucócitos/efeitos da radiação , Contagem de Linfócitos , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Linfócitos/efeitos da radiação , Macaca mulatta/virologia , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Monócitos/efeitos da radiação , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Neutrófilos/efeitos da radiação , Tacrolimo/farmacologia , Varicellovirus/efeitos dos fármacos , Varicellovirus/crescimento & desenvolvimento , Varicellovirus/efeitos da radiação , Carga Viral/efeitos dos fármacos , Carga Viral/efeitos da radiação , Ativação Viral/efeitos dos fármacos , Ativação Viral/efeitos da radiação
8.
Cancer Sci ; 105(6): 697-703, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24654677

RESUMO

This study investigated whether conformal radiotherapy affects hepatitis B virus (HBV) reactivation, and the risk factors for HBV reactivation in patients with HBV-related hepatocellular carcinoma (HCC). Sixty-nine patients with HCC were included in this retrospective study. Before radiotherapy (RT), all patients underwent imaging examinations and some baseline examinations, including CBC, liver function test, renal function test, α-fetoprotein level, hepatitis B (HB) surface antigen, HB surface Ab, HB e antigen, HB e Ab, and serum HBV DNA quantification. During the period of RT and at least 16 weeks after the end of RT, CBCs were carried out weekly and the other tests were monitored monthly or more frequently if necessary. The clinical features and dosimetric parameters of RT were recorded. Univariate and multivariate logistic regression algorithms were used to analyze the risk factors of HBV reactivation. The incidence of complications in the study population was as follows: radiation-induced liver disease, 17.4%; HBV reactivation, 24.6%; and HBV reactivation-induced hepatitis, 21.7%. The HBV DNA level and dose volume parameters including normal liver volume, V20, and mean dose were associated with HBV reactivation. There was a relatively high incidence of HBV reactivation in HCC patients after the end of conformal RT. The serum HBV DNA level and some dosimetric parameters related to normal liver, including normal liver volume, V20, and mean dose, were the prognosis factors of HBV reactivation and should be carefully considered before conformal RT.


Assuntos
Carcinoma Hepatocelular/radioterapia , Vírus da Hepatite B/efeitos da radiação , Hepatite B Crônica/virologia , Neoplasias Hepáticas/radioterapia , Radioterapia Conformacional/efeitos adversos , Ativação Viral/efeitos da radiação , DNA Viral/sangue , Feminino , Vírus da Hepatite B/genética , Vírus da Hepatite B/crescimento & desenvolvimento , Humanos , Fígado/patologia , Fígado/virologia , Hepatopatias/etiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco
9.
Cancer Immunol Immunother ; 63(3): 235-45, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24337704

RESUMO

Toll-like receptor 4 (TLR4) is an important trigger of the immune response against hepatitis B virus (HBV) infection and liver injuries. The roles of HBV reactivation versus TLR4-dependant immune response may be critical factors in preventing radiation-induced liver diseases (RILDs) after liver cancer radiotherapy. This study consists of three phases. In the primary phase, livers of mutant TLR4 (TLR4(-)) mice were irradiated with 30 Gy in either the absence or presence of HBV infection. The latter was done by introduction of plasmid pAAV/HBV 1.2. In the advanced phase, RILDs were compared in normal TLR4 (TLR4(+)) versus TLR4(-) mice. In the validation phase, 28 liver cancer patients who had undergone radiotherapy before hepatectomy were enrolled. Liver biopsies near tumors, irradiated with 35-48 Gy, were used to construct tissue microarrays. HBV reactivation, TLR4 expression, and severity of RILDs were studied in both mouse and human. More HBV reactivation, without significant RILD, was observed in irradiated versus unirradiated TLR4(-) mice. RILD scores of TLR4(+) mice were higher than TLR4(-) mice. In humans, serious RILDs tended to develop in patients with high TLR4 expression, but not in patients with low TLR4 or high HBV surface antigen expression. High TLR4 expression was seen in only 2 of 12 HBV-reactive patients, but in HBV-nonreactive patients, it was seen in 6 of 9 (P < 0.03). In summary, RILDs correlated with high TLR4 expression, but not with HBV reactivation, which is inhibited in liver with high TLR4 expression after liver cancer radiotherapy.


Assuntos
Vírus da Hepatite B/efeitos da radiação , Hepatite B Crônica/etiologia , Hepatite B Crônica/imunologia , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/radioterapia , Lesões por Radiação/etiologia , Receptor 4 Toll-Like/metabolismo , Adulto , Idoso , Animais , DNA Viral/análise , Feminino , Vírus da Hepatite B/fisiologia , Hepatite B Crônica/virologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Knockout , Análise em Microsséries , Pessoa de Meia-Idade , Mutação/genética , Lesões por Radiação/imunologia , Radioterapia/efeitos adversos , Estudos Retrospectivos , Receptor 4 Toll-Like/genética , Carga Viral , Ativação Viral/efeitos da radiação
10.
J Cell Biochem ; 114(3): 616-24, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22991253

RESUMO

Epstein-Barr virus (EBV) is the causative agent of mononucleosis and is also associated with several malignancies, including Burkitt's lymphoma, Hodgkin's lymphoma, and nasopharyngeal carcinoma, among others. EBV reactivates during spaceflight, with EBV shedding in saliva increasing to levels ten times those observed pre-and post-flight. Although stress has been shown to increase reactivation of EBV, other factors such as radiation and microgravity have been hypothesized to contribute to reactivation in space. We used a modeled spaceflight environment to evaluate the influence of radiation and microgravity on EBV reactivation. BJAB (EBV-negative) and Raji (EBV-positive) cell lines were assessed for viability/apoptosis, viral antigen and reactive oxygen species expression, and DNA damage and repair. EBV-infected cells did not experience decreased viability and increased apoptosis due to modeled spaceflight, whereas an EBV-negative cell line did, suggesting that EBV infection provided protection against apoptosis and cell death. Radiation was the major contributor to EBV ZEBRA upregulation. Combining modeled microgravity and radiation increased DNA damage and reactive oxygen species while modeled microgravity alone decreased DNA repair in Raji cells. Additionally, EBV-infected cells had increased DNA damage compared to EBV-negative cells. Since EBV-infected cells do not undergo apoptosis as readily as uninfected cells, it is possible that virus-infected cells in EBV seropositive individuals may have an increased risk to accumulate DNA damage during spaceflight. More studies are warranted to investigate this possibility.


Assuntos
Herpesvirus Humano 4/metabolismo , Voo Espacial , Ativação Viral , Simulação de Ausência de Peso , Antígenos Virais/genética , Antígenos Virais/metabolismo , Apoptose , Linfoma de Burkitt/virologia , Linhagem Celular Tumoral , Sobrevivência Celular , Dano ao DNA , Reparo do DNA , Infecções por Vírus Epstein-Barr/virologia , Herpesvirus Humano 4/genética , Humanos , Espécies Reativas de Oxigênio/metabolismo , Regulação para Cima , Proteínas Virais/metabolismo , Ativação Viral/efeitos da radiação , Latência Viral
11.
Int J Cancer ; 130(2): 443-53, 2012 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-21351100

RESUMO

The p53 tumor suppressor pathway is impaired in more than 90% of cervical cancers and cancer-derived cell lines as a result of infection by human papillomavirus (HPV). The HPV E6 oncoprotein forms complexes with p53 and promotes its degradation via ubiquitin-dependent mechanism. In our study, we attempted to improve the clinical outcomes of this combined therapy by modifying the p53-targeted adenovirus to become radiation-responsive. The antitumor adenovirus was constructed by inserting a radiation-responsive expression cassette composed of the promoter of early growth response-1 (Egr-1) and the proapoptotic protein TRAIL. We showed that the addition of adenovirus containing Egr-1/TRAIL significantly increased cell death and apoptosis caused by radiotherapy. In mice bearing xenograft tumors, intratumoral administration of the Egr-1/TRAIL adenovirus followed by radiation significantly reduced tumor growth and enhanced tumor survival. Our Egr-1/TRAIL adenoviral gene product may offer a novel "one-two punch" tumor therapy for cervical cancers not only by potentiating radiation treatment but also by preserving p53 defect-specific tumor killing of the oncolytic adenovirus.


Assuntos
Adenovírus Humanos/fisiologia , Terapia Viral Oncolítica/métodos , Neoplasias do Colo do Útero/terapia , Adenovírus Humanos/genética , Adenovírus Humanos/efeitos da radiação , Animais , Apoptose/efeitos da radiação , Terapia Combinada , Proteína 1 de Resposta de Crescimento Precoce/biossíntese , Proteína 1 de Resposta de Crescimento Precoce/genética , Feminino , Células HeLa , Humanos , Camundongos , Camundongos Nus , Regiões Promotoras Genéticas/efeitos da radiação , Ligante Indutor de Apoptose Relacionado a TNF/biossíntese , Ligante Indutor de Apoptose Relacionado a TNF/genética , Transfecção , Proteína Supressora de Tumor p53/metabolismo , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/radioterapia , Ativação Viral/efeitos da radiação , Replicação Viral
12.
J Bacteriol ; 192(4): 1122-30, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20008075

RESUMO

To determine the relative importance of temperate bacteriophage in the horizontal gene transfer of fitness and virulence determinants of Enterococcus faecalis, a panel of 47 bacteremia isolates were treated with the inducing agents mitomycin C, norfloxacin, and UV radiation. Thirty-four phages were purified from culture supernatants and discriminated using pulsed-field gel electrophoresis (PFGE) and restriction mapping. From these analyses the genomes of eight representative phages were pyrosequenced, revealing four distinct groups of phages. Three groups of phages, PhiFL1 to 3, were found to be sequence related, with PhiFL1A to C and PhiFL2A and B sharing the greatest identity (87 to 88%), while PhiFL3A and B share 37 to 41% identity with PhiFL1 and 2. PhiFL4A shares 3 to 12% identity with the phages PhiFL1 to 3. The PhiFL3A and B phages possess a high DNA sequence identity with the morphogenesis and lysis modules of Lactococcus lactis subsp. cremoris prophages. Homologs of the Streptococcus mitis platelet binding phage tail proteins, PblA and PblB, are encoded on each sequenced E. faecalis phage. Few other phage genes encoding potential virulence functions were identified, and there was little evidence of carriage of lysogenic conversion genes distal to endolysin, as has been observed with genomes of many temperate phages from the opportunist pathogens Staphylococcus aureus and Streptococcus pyogenes. E. faecalis JH2-2 lysogens were generated using the eight phages, and these were examined for their relative fitness in Galleria mellonella. Several lysogens exhibited different effects upon survival of G. mellonella compared to their isogenic parent. The eight phages were tested for their ability to package host DNA, and three were shown to be very effective for generalized transduction of naive host cells of the laboratory strains OG1RF and JH2-2.


Assuntos
Bacteriófagos/genética , Enterococcus faecalis/virologia , Genoma Viral , Prófagos/genética , Transdução Genética , Antibacterianos/farmacologia , Bacteriemia/microbiologia , Bacteriófagos/classificação , Bacteriófagos/isolamento & purificação , Impressões Digitais de DNA , DNA Viral/genética , Eletroforese em Gel de Campo Pulsado , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/isolamento & purificação , Enterococcus faecalis/efeitos da radiação , Ordem dos Genes , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Microscopia Eletrônica de Transmissão , Mitomicina/farmacologia , Dados de Sequência Molecular , Norfloxacino/farmacologia , Análise de Sequência de DNA , Homologia de Sequência , Sintenia , Raios Ultravioleta , Vírion/ultraestrutura , Ativação Viral/efeitos dos fármacos , Ativação Viral/efeitos da radiação
13.
J Neurovirol ; 16(5): 342-54, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20822371

RESUMO

Simian varicella virus (SVV) infection of primates resembles human varicella-zoster virus (VZV) infection. After primary infection, SVV becomes latent in ganglia and reactivates after immunosuppression or social and environmental stress. Herein, natural SVV infection was established in 5 cynomolgus macaques (cynos) and 10 African green (AG) monkeys. Four cynos were treated with the immunosuppressant tacrolimus (80 to 300 μg/kg/day) for 4 months and 1 was untreated (group 1). Four AG monkeys were exposed to a single dose (200 cGy) of x-irradiation (group 2), and 4 other AG monkeys were irradiated and treated with tacrolimus for 4 months (group 3); the remaining 2 AG monkeys were untreated. Zoster rash developed 1 to 2 weeks after tacrolimus treatment in 3 of 4 monkeys in group 1, 6 weeks after irradiation in 1 of 4 monkeys in group 2, and 1 to 2 weeks after irradiation in all 4 monkeys in group 3. All monkeys were euthanized 1 to 4 months after immunosuppression. SVV antigens were detected immunohistochemically in skin biopsies as well as in lungs of most monkeys. Low copy number SVV DNA was detected in ganglia from all three groups of monkeys, including controls. RNA specific for SVV ORFs 61, 63, and 9 was detected in ganglia from one immunosuppressed monkey in group 1. SVV antigens were detected in multiple ganglia from all immunosuppressed monkeys in every group, but not in controls. These results indicate that tacrolimus treatment produced reactivation in more monkeys than irradiation and tacrolimus and irradiation increased the frequency of SVV reactivation as compared to either treatment alone.


Assuntos
Varicela/induzido quimicamente , Herpes Zoster/virologia , Herpesvirus Humano 3/fisiologia , Imunossupressores/farmacologia , Tacrolimo/farmacologia , Ativação Viral/efeitos dos fármacos , Animais , Chlorocebus aethiops , Macaca fascicularis , Ativação Viral/efeitos da radiação , Latência Viral
14.
Viruses ; 12(8)2020 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-32823598

RESUMO

HIV-1 infects 39.5 million people worldwide, and cART is effective in preventing viral spread by reducing HIV-1 plasma viral loads to undetectable levels. However, viral reservoirs persist by mechanisms, including the inhibition of autophagy by HIV-1 proteins (i.e., Nef and Tat). HIV-1 reservoirs can be targeted by the "shock and kill" strategy, which utilizes latency-reversing agents (LRAs) to activate latent proviruses and immunotarget the virus-producing cells. Yet, limitations include reduced LRA permeability across anatomical barriers and immune hyper-activation. Ionizing radiation (IR) induces effective viral activation across anatomical barriers. Like other LRAs, IR may cause inflammation and modulate the secretion of extracellular vesicles (EVs). We and others have shown that cells may secrete cytokines and viral proteins in EVs and, therefore, LRAs may contribute to inflammatory EVs. In the present study, we mitigated the effects of IR-induced inflammatory EVs (i.e., TNF-α), through the use of mTOR inhibitors (mTORi; Rapamycin and INK128). Further, mTORi were found to enhance the selective killing of HIV-1-infected myeloid and T-cell reservoirs at the exclusion of uninfected cells, potentially via inhibition of viral transcription/translation and induction of autophagy. Collectively, the proposed regimen using cART, IR, and mTORi presents a novel approach allowing for the targeting of viral reservoirs, prevention of immune hyper-activation, and selectively killing latently infected HIV-1 cells.


Assuntos
Citocinas/imunologia , Vesículas Extracelulares/imunologia , HIV-1/efeitos da radiação , Radiação Ionizante , Serina-Treonina Quinases TOR/antagonistas & inibidores , Latência Viral/efeitos dos fármacos , Antivirais/farmacologia , Autofagia/efeitos dos fármacos , Benzoxazóis/farmacologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/efeitos da radiação , Linfócitos T CD4-Positivos/virologia , Vesículas Extracelulares/virologia , Feminino , HIV-1/efeitos dos fármacos , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/virologia , Masculino , Células Mieloides/efeitos dos fármacos , Células Mieloides/efeitos da radiação , Células Mieloides/virologia , Pirimidinas/farmacologia , Sirolimo/farmacologia , Células U937 , Ativação Viral/efeitos da radiação
15.
Mol Microbiol ; 68(1): 29-36, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18298445

RESUMO

Inactivation of bacteriophage lambda CI repressor leads almost exclusively to lytic development. Prophage induction can be initiated either by DNA damage or by heat treatment of a temperature-sensitive repressor. These two treatments also cause a concurrent activation of either the host SOS or heat-shock stress responses respectively. We studied the effects of these two methods of induction on the lytic pathway by monitoring the activation of different lambda promoters, and found that the lambda genetic network co-ordinates information from the host stress response networks. Our results show that the function of the CII transcriptional activator, which facilitates the lysogenic developmental pathway, is not observed following either method of induction. Mutations in the cro gene restore the CII function irrespective of the induction method. Deletion of the heat-shock protease gene ftsH can also restore CII function following heat induction but not following SOS induction. Our findings highlight the importance of the elimination of CII function during induction as a way to ensure an efficient lytic outcome. We also show that, despite the common inhibitory effect on CII function, there are significant differences in the heat- and SOS-induced pathways leading to the lytic cascade.


Assuntos
Bacteriófago lambda/genética , Ativação Viral/genética , Bacteriófago lambda/efeitos dos fármacos , Bacteriófago lambda/efeitos da radiação , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/fisiologia , Lisogenia/efeitos dos fármacos , Lisogenia/genética , Lisogenia/efeitos da radiação , Mitomicina/farmacologia , Regiões Promotoras Genéticas/genética , Proteínas Repressoras/genética , Proteínas Repressoras/fisiologia , Resposta SOS em Genética/genética , Temperatura , Fatores de Transcrição/genética , Fatores de Transcrição/fisiologia , Raios Ultravioleta , Proteínas Virais/genética , Proteínas Virais/fisiologia , Proteínas Virais Reguladoras e Acessórias/genética , Proteínas Virais Reguladoras e Acessórias/fisiologia , Ativação Viral/efeitos dos fármacos , Ativação Viral/efeitos da radiação
16.
J Neuroimmunol ; 206(1-2): 39-43, 2009 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-19042034

RESUMO

HSV-1 is a significant human pathogen that can result in the loss of sight as a result of episodic reactivation of latent virus from sensory ganglion neurons. In this study the potential efficacy of anti-viral cytokine expression in preventing latent virus reactivation was investigated. Both type I (IFN-beta) and type II (IFN-gamma) IFN transgene expression following transduction of trigeminal ganglion explant cultures significantly reduced the incident of HSV-1 reactivation that in the case of IFN-beta was dependent on the presence of double stranded RNA-dependent protein kinase and RNase L. In vivo, expression of the IFN-gamma but not IFN-beta transgene significantly delayed and reduced the frequency of reactivation of latent mice exposed to UV light without discernable inflammation. This result is the first report that demonstrates the ability to block reactivation using an ectopic cytokine expression system and warrants further exploration as a means to prevent HSV-1 reactivation.


Assuntos
Endorribonucleases/metabolismo , Herpes Simples/terapia , Herpesvirus Humano 1/fisiologia , Interferon gama/administração & dosagem , Ativação Viral/fisiologia , eIF-2 Quinase/metabolismo , Análise de Variância , Animais , Citocinas/metabolismo , Endorribonucleases/deficiência , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Vetores Genéticos/administração & dosagem , Herpes Simples/genética , Interferon beta/genética , Interferon gama/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fatores de Tempo , Transdução Genética/métodos , Raios Ultravioleta , Ativação Viral/efeitos da radiação , eIF-2 Quinase/deficiência
17.
Clin Cancer Res ; 14(4): 984-94, 2008 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-18281530

RESUMO

PURPOSE: The Epstein Barr virus (EBV) is intimately associated with nasopharyngeal cancer (NPC) in a latent state expressing a limited number of genes. The process of switching from latency to replication is not well understood, particularly in response to DNA stress; hence, the focus of this study is on an EBV-positive NPC model. EXPERIMENTAL DESIGN: C666-1 cells were exposed to radiation (2-15 Gy) or cisplatin (0.1-50 microg/mL) assayed subsequently for relative EBV copy number (BamHI) and lytic gene expression (BRLF1 and BZLF1) using quantitative real-time PCR. Chromatin immunoprecipitation was conducted to assess the interaction of the transcription factor nuclear factor-Y (NF-Y) with promoter sequences. RESULTS: Radiation-induced and cisplatin-induced BamHI expression, along with increased levels of BRLF1 and BZLF1 in a dose-dependent and time-dependent manner, associated with the immediate nuclear transactivation of the transcription factor NF-Y and its own increased transcription of NF-Y subunits 8 h posttreatment. In silico analysis revealed three putative NF-Y consensus-binding sequences in the promoter region of BRLF1, which all interacted with NF-Y in response to radiation and cisplatin, confirmed using chromatin immunoprecipitation. Introduction of dominant-negative NF-YA reduced BRLF1 expression after radiation and cisplatin by 2.8-fold; in turn, overexpression of NF-YA resulted in a 2-fold increase in both BRLF1 and BZLF1 expression. CONCLUSIONS: These results show that NF-Y is an important mediator of EBV stress response in switching from a latent to lytic state. This novel insight could provide a potential therapeutic strategy to enhance NPC response to radiation and cisplatin.


Assuntos
Fator de Ligação a CCAAT/fisiologia , Regulação Viral da Expressão Gênica , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/virologia , Fatores de Transcrição/fisiologia , Ativação Viral/fisiologia , Latência Viral/fisiologia , Animais , Antineoplásicos/farmacologia , Western Blotting , Linhagem Celular Tumoral , Cisplatino/farmacologia , Proteínas de Ligação a DNA/metabolismo , Ensaio de Imunoadsorção Enzimática , Infecções por Vírus Epstein-Barr/metabolismo , Raios gama , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/fisiologia , Expressão Gênica/efeitos da radiação , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Regulação Viral da Expressão Gênica/efeitos da radiação , Genes Virais , Herpesvirus Humano 4/efeitos dos fármacos , Herpesvirus Humano 4/fisiologia , Herpesvirus Humano 4/efeitos da radiação , Humanos , Proteínas Imediatamente Precoces/metabolismo , Imunoprecipitação , Camundongos , Camundongos SCID , Regiões Promotoras Genéticas , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transativadores/metabolismo , Proteínas Virais/metabolismo , Ativação Viral/efeitos dos fármacos , Ativação Viral/efeitos da radiação , Latência Viral/efeitos dos fármacos , Latência Viral/efeitos da radiação
18.
Technol Cancer Res Treat ; 18: 1533033819875136, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31526114

RESUMO

PURPOSE: To analyze the correlation of hepatitis B virus reactivation with patient-related and treatment-related dose-volume factors and to describe the feasibility of hepatitis B virus reactivation analyzed by a normal tissue complication probability model for patients with hepatocellular carcinoma treated with radiotherapy. MATERIALS AND METHODS: Ninety patients with hepatitis B virus-related hepatocellular carcinoma treated with radiotherapy were enrolled in this retrospective study and were followed from June 2009 to December 2015. Of the 90 patients, 78 had received conventional fractionation radiotherapy to a mean dose of 39.6 to 50.4 Gy and 12 patients were scheduled to receive hypofractionation. The physical doses were converted into 2 Gy equivalents for analysis. The parameters, TD50 (1), n, and m, of the Lyman-Kutcher-Burman normal tissue complication probability model were derived using maximum likelihood estimation. Bootstrap and leave-one-out were employed to against model overfitting and improve the model stability. RESULTS: Radiation-induced liver diseases were 17.8%, hepatitis B virus reactivation was 22.2%, and hepatitis B virus reactivation-induced hepatitis was 21.1%, respectively. In multivariate analysis, the V5Gy was associated with hepatitis B virus reactivation; TD50 (1), m, and n were 32.3, 0.55, and 0.71 Gy, respectively, for hepatitis B virus reactivation. Bootstrap and leave-one-out results showed that the hepatitis B virus parameter fits were extremely robust. CONCLUSION: A Lyman-Kutcher-Burman normal tissue complication probability model has been established to predict hepatitis B virus reactivation for patients with hepatocellular carcinoma who received radiotherapy.


Assuntos
Carcinoma Hepatocelular/radioterapia , Vírus da Hepatite B/fisiologia , Vírus da Hepatite B/efeitos da radiação , Hepatite B Crônica/virologia , Neoplasias Hepáticas/radioterapia , Ativação Viral/efeitos da radiação , Adulto , Idoso , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/etiologia , Feminino , Hepatite B Crônica/complicações , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/etiologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Razão de Chances , Curva ROC , Lesões por Radiação , Dosagem Radioterapêutica , Radioterapia Conformacional/efeitos adversos , Tomografia Computadorizada por Raios X
19.
Virus Res ; 248: 71-73, 2018 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-29476782

RESUMO

A new visible-light-induced photocatalyst based on several transition metals (iron, magnesium and manganese)-loaded TiO2 was evaluated for its anti-viral activity with influenza virus H1N1. Under a fluorescent lamp of 1000 lx, λ > 410 nm, the virus was eradicated to more than 99% within 30 min. Since this photocatalyst can be used for coating plastics, wall papers and walls, it would be desirable to use this photocatalyst to reduce viral transmission via droplets and aerosols as well as surface contact for disinfection.


Assuntos
Fluorescência , Vírus da Influenza A Subtipo H1N1/fisiologia , Vírus da Influenza A Subtipo H1N1/efeitos da radiação , Luz , Catálise , Processos Fotoquímicos , Titânio , Raios Ultravioleta , Ativação Viral/efeitos da radiação
20.
PLoS One ; 13(7): e0201316, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30059513

RESUMO

Convincing data that support routine use of preventive therapy against hepatitis B virus (HBV) reactivation in radiotherapy (RT) for hepatocellular carcinoma (HCC) are lacking. The aim of this study was to investigate the incidence, clinical significance, and risk factors of HBV reactivation after RT. Medical records of 133 HBsAg (+) HCC patients who received radiotherapy from March 2009 to February 2016 were reviewed. Patients were divided into two groups: 1) non-antiviral group, those who did not receive antiviral therapy before RT (n = 27); and antiviral group (those who underwent antiviral therapy before RT) (n = 106). Factors related to HBV reactivation in HCC patients were evaluated. 17 (12.7%) of 133 patients developed HBV reactivation after RT. Patients in the antiviral group had significantly lower rates of HBV reactivation than those in the non-antiviral group (7.5% vs. 33.3%, p<0.001). HBV related hepatitis was also lower in the antiviral group (3.8% vs. 14.8%, p = 0.031). In multivariate analysis, absence of antiviral treatment (OR: 8.339, 95% CI: 2.532-27.470, p<0.001) and combined treatment of RT with transarterial chemoembolizatoin (TACE) (OR: 5.313, 95% CI: 1.548-18.232, p = 0.008) were risk factors for HBV reactivation. HBV reactivation can occur after radiotherapy. Combination treatment of RT with TACE and non-antiviral treatment are major risk factors for HBV reactivation during or after RT. Therefore, preventive antiviral therapy should be recommended for patients with HCC who are scheduled to receive RT.


Assuntos
Antivirais/administração & dosagem , Carcinoma Hepatocelular/radioterapia , Quimioembolização Terapêutica , Vírus da Hepatite B/fisiologia , Hepatite B/terapia , Neoplasias Hepáticas/radioterapia , Ativação Viral , Idoso , Carcinoma Hepatocelular/virologia , Feminino , Hepatite B/etiologia , Humanos , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Ativação Viral/efeitos dos fármacos , Ativação Viral/efeitos da radiação
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