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1.
Injury ; 53 Suppl 1: S23-S28, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32993969

RESUMO

INTRODUCTION: Conversion Total Hip Arthroplasty (cTHA) is a rescue strategy for proximal femur osteosynthesis failures. However, it is unclear whether cTHAs performed for extra-capsular fracture fixation failures (ECF) or for intra-capsular fracture fixation failures (ICF) share the same complexity and efficacy. The purpose of our study was to compare cTHAs performed on pre-existing ICFs and pre-existing ECFs, focusing on surgical complications and functional outcomes in both groups. METHODS: An observational retrospective study was conducted on cTHA patients, treated between 2014 and 2018, divided into 2 groups: ICF-group and ECF-group. The main outcomes were: type of implant used, duration of surgery, need for transfusions, incidence of complications, functional outcomes. RESULTS: 28 patients were included (15 in the ECF group and 13 in the ICF group); the average follow-up was of 31 ± 17.3 months. No significant differences were identified in terms of the type of implant used and duration of surgery. The number of transfused patients was 4 in the ICF group and 12 in the ECF group (p = 0.02); the average transfused units were 0.4 ± 0.7 in the ICF group and 1.3 ± 0.9 in the ECF group (p = 0.01). The incidence of complications - an infection and a dislocation, both of which occurred in the ICF group - and functional outcomes did not present significant differences. CONCLUSION: The conversion surgery on ECFs patients is technically more difficult for the surgeon and prone to greater blood loss. The outcomes are satisfactory and overlap between the two groups.


Assuntos
Artroplastia de Quadril , Fraturas do Quadril , Artroplastia de Quadril/efeitos adversos , Fixação Interna de Fraturas/efeitos adversos , Fraturas do Quadril/cirurgia , Humanos , Reoperação , Estudos Retrospectivos
2.
Clin Ter ; 168(1): e8-e13, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28240756

RESUMO

INTRODUCTION: Osteoarticular infections are found frequently in drug addicted individuals, representing one of the main reasons for their hospitalization. Through inoculation, the pathogenic agents can enter the individual's system directly through the skin or parenterally, transmitted, that is, through syringes and other objects used during such practice. In these particular conditions, or when the medical history is vague, a warranted suspicion and the execution of targeted research can help in the diagnosis of high-risk patients such as addicts. DISCUSSION: With this paper, the Authors are presenting a case of septic arthritis in the hip joint, in a drug addicted patient with the habit of injecting narcotics into the femoral vein, in correspondence of the anatomical region known as the triangle of Scarpa. Following an examination of the bacterial culture samples taken by arthrocentesis, the S. Aureus infection was identified and a targeted antibiotic therapy (coxacillin and aminoglycosides) was prescribed. After one year, with clinical examination and medical scans resulting negative for infection, there was a remaining deformity of the femoral head and, therefore, a total hip arthroplasty (THA) was performed. The 14 year post-operative clinical examination and medical scan check-up showed a complete articular functionality and recovery of normal daily and work related activities.


Assuntos
Antibacterianos/uso terapêutico , Artrite Infecciosa/diagnóstico , Usuários de Drogas , Adulto , Artrite Infecciosa/terapia , Artroplastia de Quadril/métodos , Seguimentos , Articulação do Quadril , Humanos , Masculino , Staphylococcus aureus/isolamento & purificação
3.
Eur J Clin Microbiol Infect Dis ; 35(8): 1247-58, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27234593

RESUMO

Laboratory-acquired infections due to a variety of bacteria, viruses, parasites, and fungi have been described over the last century, and laboratory workers are at risk of exposure to these infectious agents. However, reporting laboratory-associated infections has been largely voluntary, and there is no way to determine the real number of people involved or to know the precise risks for workers. In this study, an international survey based on volunteering was conducted in biosafety level 3 and 4 laboratories to determine the number of laboratory-acquired infections and the possible underlying causes of these contaminations. The analysis of the survey reveals that laboratory-acquired infections have been infrequent and even rare in recent years, and human errors represent a very high percentage of the cases. Today, most risks from biological hazards can be reduced through the use of appropriate procedures and techniques, containment devices and facilities, and the training of personnel.


Assuntos
Pesquisa Biomédica , Laboratórios , Doenças Profissionais , Exposição Ocupacional , Pesquisa Biomédica/normas , Pesquisa Biomédica/estatística & dados numéricos , Contenção de Riscos Biológicos , Estudos Transversais , Humanos , Laboratórios/normas , Laboratórios/estatística & dados numéricos , Doenças Profissionais/epidemiologia , Doenças Profissionais/microbiologia , Doenças Profissionais/prevenção & controle , Doenças Profissionais/virologia , Exposição Ocupacional/prevenção & controle , Exposição Ocupacional/normas , Exposição Ocupacional/estatística & dados numéricos , Equipamento de Proteção Individual/normas , Equipamento de Proteção Individual/estatística & dados numéricos , Medição de Risco , Segurança , Inquéritos e Questionários
4.
J Parasitol ; 101(4): 488-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25764145

RESUMO

Here we report the case of a 42-yr-old patient who presented himself to us with a serpiginous erythematous lesion from the wrist of the right forearm up the arm to the right shoulder A similar lesion of a smaller size was also present in the left forearm. On the basis of clinical manifestations and progression of the lesion, combined with previous treatments and different diagnostic investigations, hookworm-related cutaneous larva migrans (HrCLM) disease was hypothesized. Albendazole was employed as treatment and the resolution of the symptoms confirmed the diagnosis. The relevance of the reported case relies on 3 main aspects: the acquisition of the disease in Italy, the initial treatment with topical corticosteroids that sped up the progression of the cutaneous trail, and the uncommon location of the lesions. Furthermore, the anamnestic data and the laboratory/clinical investigations strongly suggested an occupational exposure to the etiological agent. As illustrated here, HrCLM might represent a challenge for Western physicians in terms of diagnosis, treatment, and ways of acquisition. Describing the clinical presentation and the treatment of cases of cutaneous larva migrans might contribute to early and correct diagnosis, to an increase of our knowledge on this disease, and to an update on its epidemiology.


Assuntos
Infecções por Uncinaria/complicações , Larva Migrans/diagnóstico , Doenças Profissionais/diagnóstico , Corticosteroides/administração & dosagem , Corticosteroides/efeitos adversos , Adulto , Albendazol/uso terapêutico , Animais , Anticestoides/uso terapêutico , Braço , Diagnóstico Diferencial , Antebraço , Humanos , Itália , Larva Migrans/tratamento farmacológico , Larva Migrans/parasitologia , Masculino , Doenças Profissionais/tratamento farmacológico , Doenças Profissionais/parasitologia , Exposição Ocupacional , Manejo de Espécimes/efeitos adversos , Polegar , Zoologia
5.
J Cell Physiol ; 230(8): 1794-806, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25510868

RESUMO

Similar to phosphorylation, transient conjugation of ubiquitin to target proteins (ubiquitination) mediated by the concerted action of ubiquitin ligases and de-ubiquitinating enzymes (DUBs) can affect substrate function. As obligate intracellular parasites, viruses rely on different cellular pathways for their own replication and the well conserved ubiquitin conjugating/de-conjugating system is not an exception. Viruses not only usurp the host proteins involved in the ubiquitination/de-ubiquitination process, but they also encode their own ubiquitin ligases and DUBs. Here we report that an N-terminal variant of the herpes simplex virus (HSV) type-1 large tegument protein VP1/2 (VP1/2(1-767)), encompassing an active DUB domain (herpesvirus tegument ubiquitin specific protease, htUSP), and TSG101, a component of the endosomal sorting complex required for transport (ESCRT)-I, functionally interact. In particular, VP1/2(1-767) modulates TSG101 ubiquitination and influences its intracellular distribution. Given the role played by the ESCRT machinery in crucial steps of both cellular pathways and viral life cycle, the identification of TSG101 as a cellular target for the HSV-1 specific de-ubiquitinating enzyme contributes to the clarification of the still under debate function of viral encoded DUBs highly conserved throughout the Herpesviridae family.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Interações Hospedeiro-Parasita/fisiologia , Simplexvirus/patogenicidade , Fatores de Transcrição/metabolismo , Proteases Específicas de Ubiquitina/metabolismo , Proteínas Virais/metabolismo , Animais , Chlorocebus aethiops , Humanos , Imunoprecipitação , Microscopia Confocal , Reação em Cadeia da Polimerase em Tempo Real , Simplexvirus/metabolismo , Ubiquitinação , Células Vero
6.
Gene Ther ; 21(3): 272-81, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24430237

RESUMO

Corneal graft rejection is a major problem in chronic herpetic keratitis (HK) patients with latent infection. A new class of antiviral agents targeting latent and active forms of herpes simplex virus type 1 (HSV-1) is importantly required. Meganucleases are sequence-specific homing endonucleases capable of inducing DNA double-strand breaks. A proof-of-concept experiment has shown that tailor-made meganucleases are efficient against HSV-1 in vitro. To take this work a step forward, we hypothesized that the pre-treatment of human corneas in eye banks using meganuclease-encoding vectors will allow HK patients to receive a medicated cornea to resist the recurrence of the infection and the common graft rejection problem. However, this strategy requires efficient gene delivery to human corneal endothelium. Using recombinant adeno-associated virus, serotype 2/1 (rAAV2/1), efficient gene delivery of a reporter gene was demonstrated in human corneas ex vivo. The optimum viral dose was 3.7 × 10(11) VG with an exposure time of 1 day, followed by 6 days incubation in de-swelling medium. In addition, 12 days incubation can result in transgene expression in excess of 70%. Using similar transduction conditions, meganuclease transgene expression was detected in 39.4% of the endothelial cells after 2 weeks in culture. Reduction of the total viral load in the media and the endothelial cells of corneas infected with HSV-1 was shown. Collectively, this work provides information about the optimum conditions to deliver genetic material to the cornea, and demonstrates for the first time the expression of meganuclease in human corneas ex vivo and its antiviral activity. In conclusion, we demonstrate that the treatment of human corneas in eye banks before transplantation is a new approach to address the unmet clinical needs in corneal diseases.


Assuntos
Córnea/metabolismo , Desoxirribonuclease I/genética , Proteínas Virais/genética , Desoxirribonuclease I/metabolismo , Dependovirus/genética , Dependovirus/metabolismo , Técnicas de Transferência de Genes , Genes Reporter/genética , Herpesvirus Humano 1/enzimologia , Humanos , Técnicas In Vitro , Proteínas Virais/metabolismo
7.
Int J Hyg Environ Health ; 217(1): 17-22, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23540488

RESUMO

Influenza virus spreads via small particle aerosols, droplets and fomites, and since it can survive for a short time on surfaces, can be introduced into the nasal mucosa before it loses infectivity. The hypothiocyanite ion (OSCN-), product of the lactoperoxidase/H2O2/SCN- system of central airways, is emerging as an important molecule for innate defense mechanism against bacteria, fungi and viruses. Here we demonstrated that OSCN(-) displays virucidal activity in vitro against the A/H1N1 2009 pandemic influenza virus. The concentration required to inhibit viral replication by 50% was 2 µM when virus were challenged directly with OSCN- before cell inoculation. These values were even lower when inoculated cells were maintained in contact with enzyme free-OSCN- in the culture medium. The last experimental conditions better reflect those of tracheobronchial mucosa, where HOSCN/OSCN- is retained in the air-liquid interface and inactivates both the viruses approaching the epithelium from outside and those released from the inoculated cells after the replication cycle. Importantly no OSCN- cytotoxicity was observed in the cellular system employed. The lack of toxicity in humans and the absence of damage on surfaces of fomites suggest a potential use of OSCN- to avoid mucosal and environmental transmission of influenza virus. Since hypothiocyanite is normally present in human airways a low risk of viral resistance is envisaged. In vivo confirmatory studies are needed to evaluate the appropriate dose, regimen and formulation.


Assuntos
Antivirais/farmacologia , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Tiocianatos/farmacologia , Animais , Linhagem Celular , Cães , Vírus da Influenza A Subtipo H1N1/fisiologia , Pandemias , Internalização do Vírus/efeitos dos fármacos
8.
Bone Joint J ; 95-B(10): 1332-8, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24078528

RESUMO

A retrospective study was conducted to investigate the changes in metal ion levels in a consecutive series of Birmingham Hip Resurfacings (BHRs) at a minimum ten-year follow-up. We reviewed 250 BHRs implanted in 232 patients between 1998 and 2001. Implant survival, clinical outcome (Harris hip score), radiographs and serum chromium (Cr) and cobalt (Co) ion levels were assessed. Of 232 patients, 18 were dead (five bilateral BHRs), 15 lost to follow-up and ten had been revised. The remaining 202 BHRs in 190 patients (136 men and 54 women; mean age at surgery 50.5 years (17 to 76)) were evaluated at a minimum follow-up of ten years (mean 10.8 years (10 to 13.6)). The overall implant survival at 13.2 years was 92.4% (95% confidence interval 90.8 to 94.0). The mean Harris hip score was 97.7 (median 100; 65 to 100). Median and mean ion levels were low for unilateral resurfacings (Cr: median 1.3 µg/l, mean 1.95 µg/l (< 0.5 to 16.2); Co: median 1.0 µg/l, mean 1.62 µg/l (< 0.5 to 17.3)) and bilateral resurfacings (Cr: median 3.2 µg/l, mean 3.46 µg/l (< 0.5 to 10.0); Co: median 2.3 µg/l, mean 2.66 µg/l (< 0.5 to 9.5)). In 80 unilateral BHRs with sequential ion measurements, Cr and Co levels were found to decrease significantly (p < 0.001) from the initial assessment at a median of six years (4 to 8) to the last assessment at a median of 11 years (9 to 13), with a mean reduction of 1.24 µg/l for Cr and 0.88 µg/l for Co. Three female patients had a > 2.5 µg/l increase of Co ions, associated with head sizes ≤ 50 mm, clinical symptoms and osteolysis. Overall, there was no significant difference in change of ion levels between genders (Cr, p = 0.845; Co, p = 0.310) or component sizes (Cr, p = 0.505; Co, p = 0.370). Higher acetabular component inclination angles correlated with greater change in ion levels (Cr, p = 0.013; Co, p = 0.002). Patients with increased ion levels had lower Harris hip scores (p = 0.038). In conclusion, in well-functioning BHRs the metal ion levels decreased significantly at ten years. An increase > 2.5 µg/l was associated with poor function.


Assuntos
Artroplastia de Quadril/efeitos adversos , Prótese de Quadril/efeitos adversos , Metais/sangue , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Cromo/sangue , Cobalto/sangue , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite do Quadril/cirurgia , Período Pós-Operatório , Falha de Prótese , Reoperação , Estudos Retrospectivos , Fatores Sexuais , Resultado do Tratamento , Adulto Jovem
10.
Br J Ophthalmol ; 93(2): 244-8, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19174401

RESUMO

BACKGROUND: Vascular endothelial growth factor (VEGF) has been shown to play a major role in the pathological neovascularisation that occurs in degenerative retinal diseases like age-related macular degeneration (AMD). Although several approaches to attenuate VEGF show significant promise, repeated treatments are required to achieve therapeutic benefits. As lentiviruses efficiently and stably infect resting cells, a human immunodeficiency virus type 1 (HIV-1)-based vector was used for the delivery and long-term endogenous expression of a short hairpin RNA (shRNA) specific for VEGF in postmitotic human retinal pigment epithelium (RPE) cells. METHODS: An HIV-1 vector expressing a shRNA targeting VEGF was developed and adopted to transduce RPE cell cultures, in both normoxic and hypoxic conditions in vitro. Intracellular VEGF expression was analysed by western blotting, and the release of VEGF in culture supernatants was determined by ELISA. RESULTS: At least 90% of RPE cells were successfully transduced by HIV-1 virions. Inhibition of VEGF expression and reduction by 95% of VEGF release in transduced cells were achieved. Moreover, shRNA-VEGF effectively and specifically prevented hypoxia-induced VEGF upregulation. CONCLUSION: HIV-1-mediated delivery of a shRNA-VEGF leading to gene expression knockdown could represent a novel therapeutic strategy against neovascularisation-related eye diseases.


Assuntos
Técnicas de Silenciamento de Genes/métodos , HIV-1/genética , Epitélio Pigmentado da Retina/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Células Cultivadas , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Inativação Gênica , Vetores Genéticos , Humanos , Sequências Repetidas Invertidas/genética , RNA Interferente Pequeno/genética , Epitélio Pigmentado da Retina/citologia , Fator A de Crescimento do Endotélio Vascular/genética
11.
Gene Ther ; 16(2): 279-90, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19037240

RESUMO

Recombinant Semliki Forest virus (SFV) is an attractive viral vector system owing to its ability to allow high efficiency of viral protein expression. To produce recombinant pseudotyped human immunodeficiency virus type 1 (HIV-1) virions, we designed a chimeric SFV/HIV vector system that contains both the HIV-1 cis- and trans-acting elements under the transcriptional control of the SFV replicase and investigated the ability of the hybrid SFV/HIV system to produce lentiviral particles capable of transducing target cells. Co-transfection of target cells with the two helper SFV packaging system RNAs along with each SFV/Gag-Pol, SFV/VSV(G) as well as SFV/HIV-1 vector unit replicon led to the generation of efficient transducing competent recombinant SFV/HIV particles. In contrast, co-transduction of target cells with the SFV/HIV chimeric virions produced recombinant particles with low transducing ability. Our data suggest that both the genomic and the subgenomic RNAs containing the HIV-1 vector unit were negatively selected for incorporation into recombinant particles, despite the fact that the SFV-driven HIV-1 vector replicon was the only one containing a lentiviral packaging sequence. The results of this study provide insights relevant to the design of chimeric lentiviral vectors.


Assuntos
HIV-1/genética , Vírus da Floresta de Semliki/genética , Transativadores/biossíntese , Linhagem Celular , Vetores Genéticos/genética , Humanos , Recombinação Genética , Replicon/genética , Transativadores/genética , Transdução Genética , Vírion/genética
12.
Rev Med Virol ; 19(1): 31-45, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18618839

RESUMO

As an enveloped virus buds, the nascent viral capsid becomes wrapped in a plasma membrane-derived lipid envelope, and a membrane fission event is thus necessary to separate the virion from the host cell. This membrane fission event is well characterised in the case of enveloped RNA viruses, where it is promoted by late assembly domains (L-domains) present at the level of specific viral structural proteins. Research conducted over the past 10 years has demonstrated that L-domains represent docking sites for cellular proteins essential for the biogenesis of a cellular organelle, the multivesicular body (MVB). In this way, enveloped RNA viruses hijack the MVB components to the cellular site where the budding is executed. This review will focus on the cellular machinery exploited by enveloped RNA viruses in order to be released from infected cells. The role of ubiquitin and lipids in viral budding will also be discussed.


Assuntos
Endossomos/virologia , Interações Hospedeiro-Patógeno , Vírus de RNA/fisiologia , Montagem de Vírus , Animais , Humanos
14.
Gene Ther ; 13(14): 1080-7, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16554839

RESUMO

The ability of viruses to selectively target, replicate within, and destroy tumour cells without deleterious effects in normal cells (oncolysis), makes the use of viruses as an attractive tool for cancer treatment. Pancreatic adenocarcinoma, being insensitive to traditional therapy and having a rather poor prognosis, represents a suitable target to evaluate viral oncolysis as a novel therapeutic approach. Herpes simplex virus (HSV) has been reported to produce an oncolytic effect in cells overexpressing Ras. As Ras signalling is frequently aberrant in pancreatic cancer, we compared four pancreatic cell lines (which differ in the presence of mutated or wild-type ras) for their ability to support growth of gamma34.5-replication attenuated HSV-1 (R3616). Our data show that permissiveness to viral replication is neither associated with enhanced Ras signalling nor with defective PKR activity. By contrast, we provide evidence that disregulation of the PI 3-kinase signalling pathway allows conditionally replication-defective R3616 virus to overcome the cellular antiviral activity.


Assuntos
Adenocarcinoma/terapia , Terapia Genética/métodos , Herpesvirus Humano 1/genética , Terapia Viral Oncolítica/métodos , Neoplasias Pancreáticas/terapia , Fosfatidilinositol 3-Quinases/metabolismo , Adenocarcinoma/enzimologia , Adenocarcinoma/virologia , Linhagem Celular Tumoral , Cromonas/uso terapêutico , Flavonoides/uso terapêutico , Deleção de Genes , Genes ras , Herpes Simples/complicações , Humanos , Immunoblotting/métodos , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Morfolinas/uso terapêutico , Neoplasias Pancreáticas/enzimologia , Neoplasias Pancreáticas/virologia , Inibidores de Fosfoinositídeo-3 Quinase , Transdução de Sinais , Proteínas Virais/genética , Replicação Viral/genética
15.
Eur Spine J ; 14(2): 151-4, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15759172

RESUMO

Back Pain (BP) is one of the most frequent symptoms during the last period of pregnancy, and high incidence has been described in several studies. Until now no wide, multicenter and prospective clinical studies on the natural course of BP after pregnancy have been available. We performed a multicenter follow-up study in a sample of pregnant women using the Italian validated version of the Roland questionnaire to assess the evolution of BP after pregnancy and identify prognostic factors. Each center had to re-evaluate at least 75% of the initially enrolled women, with latency of 1 year after delivery. At the follow-up, we acquired substantial clinical data concerning the post-delivery period. The evaluation of symptom evolution was based on the Roland questionnaire. At follow-up, 53% of re-evaluated women had no BP symptoms. Moreover, there was a significant improvement of patient-oriented assessment in women who suffered BP after delivery. With regard to the predictive factors, the presence of BP before pregnancy implied a 3.1-fold higher probability of improvement after delivery. In conclusion, women without history of BP before pregnancy and who complain of these symptoms during pregnancy require greater attention, because they have a lower possibility for improvement. Conversely, in women with a history of BP, pregnancy represents a transient period of worsening symptoms, probably due to the temporary para-physiological mechanical condition.


Assuntos
Dor nas Costas/fisiopatologia , Complicações na Gravidez/fisiopatologia , Feminino , Seguimentos , Humanos , Período Pós-Parto/fisiologia , Gravidez , Prognóstico , Estudos Prospectivos , Inquéritos e Questionários
16.
J Neurovirol ; 8(3): 180-90, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12053273

RESUMO

Brain resistance to intracerebral superinfections develops after a peripheral inoculation of neurovirulent viruses. Superinfection resistance combines specificity, toward the virus used for the peripheral inoculum, and short-term duration after the inoculum. In order to study this unusual combination, neurovirulent superinfections were made on albino Swiss mice previously infected with a nasal inoculum. A herpesvirus strain SC16, or a homologue recombinant virus carrying the reporter lac Z gene or a vesicular stomatitis virus (VSV) (a virus taxonomically unrelated to Herpesviridae) were used. The mice underwent a neurological examination and their survival rate was recorded. The brains superinfected with the reporter virus were stained for the beta-galactosidase reaction to trace the virus spread and the inflammatory infiltrates were characterized immunocytochemically. The results confirm and extend previous observations about virus specificity and short-term duration of superinfection resistance. They show, moreover, an enhanced brain inflammation with T-cells and macrophages infiltrating the tissue around microvessels, at a time when both neurovirulence and the spread of herpesvirus in the brain are reduced. The results suggest that the immune response to superinfection in the nervous tissue is enhanced by blood-brain barrier mechanisms that promote the timely extravasation of immune cells.


Assuntos
Encéfalo/imunologia , Encéfalo/virologia , Encefalite por Herpes Simples/imunologia , Encefalite por Herpes Simples/fisiopatologia , Herpesvirus Humano 1 , Animais , Barreira Hematoencefálica , Encéfalo/irrigação sanguínea , Modelos Animais de Doenças , Orelha Externa/virologia , Encefalite por Herpes Simples/mortalidade , Genes Reporter , Imunidade Inata/imunologia , Camundongos , Camundongos Endogâmicos , Superinfecção/imunologia , Superinfecção/mortalidade , Superinfecção/fisiopatologia , beta-Galactosidase/genética
17.
Scand J Infect Dis ; 33(10): 794-6, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11728057

RESUMO

Several type-specific serologic assays for herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2), based on glycoprotein G1 (gG1) and gG2, have recently been developed. These include immunodot (POCkit HSV-2) and enzyme-linked immunosorbent assay (ELISA). The diagnostic value of POCkit HSV-2, a near-patient test, and of 2 immunoenzymatic, type-specific assays was evaluated on 122 patients attending an STD clinic. Western blot was used as the reference test. The sensitivity of POCkit HSV-2 was good but the specificity was poor, so that in a population with low seroprevalence, a positive result is likely to be a false positive. Analysis of 2 currently available HSV type-specific ELISAs yielded results suggesting that the sensitivity of these tests may also be suboptimal.


Assuntos
Anticorpos Antivirais/análise , Ensaio de Imunoadsorção Enzimática/métodos , Herpesvirus Humano 1/imunologia , Herpesvirus Humano 2/imunologia , Kit de Reagentes para Diagnóstico , Western Blotting/métodos , Método Duplo-Cego , Humanos , Sensibilidade e Especificidade
18.
Herpes ; 8(2): 50-5, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11867019

RESUMO

Herpes simplex virus types 1 and 2 (HSV-1 and -2) are two of the major opportunistic agents involved in the pathogenesis of AIDS, which is caused by human immunodeficiency virus types 1 and 2 (HIV-1 and HIV-2). A body of evidence suggests that they can also act as co-factors by interacting with HIV-1, thereby influencing disease progression. Indeed, the HIV-1 life cycle can be affected by HSV at different levels of interaction, both in vitro and in vivo: (i) transactivation of the HIV-1 long terminal repeat can be mediated, probably through different pathways, by HSV-1-infected cell protein (ICP)0, ICP4, ICP27 and US11 gene products; the HSV-1 transactivator viral protein 16 is not able to transactivate the long terminal repeat; (ii) cytokine release and antigen presentation from HSV-infected cells are both able to stimulate HIV-1 expression; (iii) Pseudotyping of the HIV-1 core particle with HSV-1 envelope glycoproteins can expand HIV-1 tropism to new cell types. Moreover, in vivo studies report that aciclovir treatment can produce a survival benefit in HIV-1-infected patients and that recurrent genital herpes appears to be linked to HIV-1 transmission by both boosting plasma retroviral load and providing a portal of entry and exit for HIV-1.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/metabolismo , HIV-1/metabolismo , HIV-2/metabolismo , Herpes Simples/metabolismo , Herpesvirus Humano 1/metabolismo , Herpesvirus Humano 2/metabolismo , Citocinas/metabolismo , Progressão da Doença , Humanos , Recidiva , Ativação Transcricional
19.
Proc Natl Acad Sci U S A ; 97(24): 13063-8, 2000 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-11087860

RESUMO

Retroviral Gag polyproteins have specific regions, commonly referred to as late assembly (L) domains, which are required for the efficient separation of assembled virions from the host cell. The L domain of HIV-1 is in the C-terminal p6(gag) domain and contains an essential P(T/S)AP core motif that is widely conserved among lentiviruses. In contrast, the L domains of oncoretroviruses such as Rous sarcoma virus (RSV) have a more N-terminal location and a PPxY core motif. In the present study, we used chimeric Gag constructs to probe for L domain activity, and observed that the unrelated L domains of RSV and HIV-1 both induced the appearance of Gag-ubiquitin conjugates in virus-like particles (VLP). Furthermore, a single-amino acid substitution that abolished the activity of the RSV L domain in VLP release also abrogated its ability to induce Gag ubiquitination. Particularly robust Gag ubiquitination and enhancement of VLP release were observed in the presence of the candidate L domain of Ebola virus, which contains overlapping P(T/S)AP and PPxY motifs. The release defect of a minimal Gag construct could also be corrected through the attachment of a peptide that serves as a physiological docking site for the ubiquitin ligase Nedd4. Furthermore, VLP formation by a full-length Gag polyprotein was sensitive to lactacystin, which depletes the levels of free ubiquitin through inhibition of the proteasome. Our findings suggest that the engagement of the ubiquitin conjugation machinery by L domains plays a crucial role in the release of a diverse group of enveloped viruses.


Assuntos
Vírus do Sarcoma Aviário/fisiologia , Ebolavirus/fisiologia , Produtos do Gene gag/metabolismo , HIV-1/fisiologia , Ligases/metabolismo , Replicação Viral/fisiologia , Sequência de Aminoácidos , Sequência Conservada , Produtos do Gene gag/química , Células HeLa , Humanos , Dados de Sequência Molecular , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Transfecção , Ubiquitina-Proteína Ligases , Ubiquitinas/metabolismo , Vírion/fisiologia
20.
J Med Chem ; 43(20): 3799-802, 2000 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-11020296

RESUMO

A series of 6-aminoquinolone compounds were evaluated for their in vitro activity against human immunodeficiency virus type 1 (HIV-1). Compound 12a, bearing a methyl substituent at the N-1 position and a 4-(2-pyridyl)-1-piperazine moiety at the C-7 position, was the most active in inhibiting HIV-1 replication on de novo infected C8166 human lymphoblastoid cell lines. The 12a EC(50) value was 0.1 microM, a 7-20-fold lower concentration relative to that for compounds 8a and 7a containing a cyclopropyl and tert-butyl substituent at the N-1 position, respectively. When the C-6 amino group was replaced with a fluorine atom, a decreased antiviral effect was observed. The observed effects are selective, since potency is substantially reduced when testing the compounds against the herpes simplex virus type 1 (HSV-1). Active quinolone derivatives very efficiently interact with TAR RNA, which suggests a nucleic acid-targeted mechanism of action.


Assuntos
Fármacos Anti-HIV/síntese química , Piperazinas/síntese química , Quinolonas/síntese química , Inibidores da Transcriptase Reversa/síntese química , Animais , Fármacos Anti-HIV/química , Fármacos Anti-HIV/farmacologia , Linhagem Celular , Chlorocebus aethiops , DNA Viral/química , HIV-1/efeitos dos fármacos , Herpesvirus Humano 1/efeitos dos fármacos , Piperazinas/química , Piperazinas/farmacologia , Quinolonas/química , Quinolonas/farmacologia , RNA Viral/química , Inibidores da Transcriptase Reversa/química , Inibidores da Transcriptase Reversa/farmacologia , Espectrometria de Fluorescência , Relação Estrutura-Atividade , Células Vero
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