Generation of herpesvirus entry mediator (HVEM)-restricted herpes simplex virus type 1 mutant viruses: resistance of HVEM-expressing cells and identification of mutations that rescue nectin-1 recognition.

Both initial infection and cell-to-cell spread by herpes simplex virus type 1 (HSV-1) require the interaction of the viral glycoprotein D (gD) with an entry receptor on the cell surface. The two major HSV entry receptors, herpesvirus entry mediator (HVEM) and nectin-1, mediate infection independently but are coexpressed on a variety of cells. To determine if both receptors are active in these instances, we have established mutant viruses that are selectively impaired for recognition of one or the other receptor. In plaque assays, these viruses showed approximately 1,000-fold selectivity for the matched receptor over the mismatched receptor. Separate assays showed that each virus is impaired for both infection and spread through the mismatched receptor. We tested several human tumor cell lines for susceptibility to these viruses and observed that HT29 colon carcinoma cells are susceptible to infection by nectin-1-restricted virus but are highly resistant to HVEM-restricted virus infection, despite readily detectable HVEM expression on the cell surface. HVEM cDNA isolated from HT29 cells rendered HSV-resistant cells permissive for infection by the HVEM-restricted virus, suggesting that HT29 cells lack a cofactor for HVEM-mediated infection or express an HVEM-specific inhibitory factor. Passaging of HVEM-restricted virus on nectin-1-expressing cells yielded a set of gD missense mutations that each restored functional recognition of nectin-1. These mutations identify residues that likely play a role in shaping the nectin-1 binding site of gD. Our findings illustrate the utility of these receptor-restricted viruses in studying the early events in HSV infection

Tamponamento cardíaco tardio traumático: análise de cinco casos Traumatic late cardiac tamponade: analysis of five cases

São analisados cinco casos de tamponamento cardíaco tardio traumático. Os pacientes eram masculinos, idade média de 26,2 anos, vítimas de ferimento por arma branca em região precordial, área de Ziedler, sendo admitidos em centro de referência para trauma. Foram classificados pelo índice fisiológico de Ivatury para trauma cardíaco e inicialmente tratados por pleurotomia intercostal e reposição volêmica, com estabilização do quadro hemodinâmico e respiratório. Os pacientes foram readmitidos após intervalo de oito a 24 dias (mediana de 20 dias), agora no serviço de cirurgia torácica de um hospital de referência terciária, com sinais de tamponamento cardíaco. Os exames diagnósticos confirmaram derrame pericárdico com espessamento pericárdico associado a encarceramento de base pulmonar esquerdo em quatro casos, os quais foram abordados por toracotomia póstero-lateral, com realização de pericardiectomia parcial e descorticação pulmonar. Um paciente evoluiu com pericardite purulenta, comprovada por exames complementares, e foi submetido à drenagem pericárdica subxifóidea. Ocorreu arritmia pós-operatória em um paciente; os demais evoluíram sem complicações pós-operatórias ou recidiva do tamponamento.<br>Five traumatic late cardiac tamponade cases were analyzed. All patients were male, mean age was 26.2, victims of thoracic penetrating stabbing wound in the precordial region, Ziedler area, admitted to a trauma reference center. They were classified by the Ivatury physiological index for cardiac trauma. The first treatment approach was intercostal pleurectomy and volemic resuscitation followed by hemodynamic and respiratory recovery. Patients with cardiac tamponade symptoms were re-admitted within an interval from eight to twenty four days (mean 20 days) in a thoracic surgery service of a tertiary reference hospital. Diagnostic exams confirmed thickening and pericardial effusion associated with a left pulmonary base entrapment in four of the cases which were treated by posterolateral thoracotomy, including partial pericardiectomy and pulmonary decortication. One patient was diagnosed with purulent pericarditis by supplementary exams and underwent a subxiphoid pericardial drainage. Postoperative cardiac arrhythmia occurred in one patient but the others did not develop any complications and there were no tamponade recurrent cases

Febre crônica associada a abscesso esplênico causado por Staphylococcus epidermidis Chronic fever associated with splenic abscess due to Staphylococcus epidermidis

Abscessos ocultos são causa freqüente de febre crônica. Os abscessos esplênicos são entidades raras, usualmente associadas a quadros subjacentes de cirurgia abdominal, endocardite ou imunodepressão. Apresenta-se um caso de paciente com febre prolongada causada por um abscesso esplênico, cujo principal diagnóstico diferencial era leishmaniose visceral, que provavelmente esteve associado a traumatismo abdominal. O tratamento consistiu em antibioticoterapia seguida de esplenectomia.<br>Occult abscesses are frequent causes of chronic fever. Splenic abscesses are rare entities that are usually associated with underlying conditions such as abdominal surgery, endocarditis or immunodepression. We report on the case of a patient with prolonged fever caused by a splenic abscess, whose main differential diagnosis was visceral leishmaniasis. However, this condition was probably related to abdominal trauma. The treatment consisted of antibiotics followed by splenectomy