Specific and non-specific immunity and protection of macaques against SIV infection.

The simian immunodeficiency virus is a retrovirus closely related to the human immunodeficiency viruses; it induces an AIDS-like disease in macaques, and provides therefore an obvious animal model for anti-lentiviral drug and vaccine strategy assessments. In our experiment, we immunized rhesus macaques with a purified and formalin-inactivated whole SIVmac251 antigen preparation. Most of these monkeys were still protected for more than 4 months following a heterologous SIVsm intravenous challenge. Both virus stocks, for vaccine preparation and challenge, were provided by culture supernatants of infected T cells of human origin. Four of the protected macaques were then reimmunized with the same antigen preparation and rechallenged intravenously with a homologous rhesus cell grown SIVmac251. Unexpectedly, all animals developed clinical and biological evidence of infection by day 15 after the second challenge.     

The metabolic fate of an oral 14C-alanine load in the obese Zucker rat.

Following an oral 14C-alanine load, obese Zucker rats showed the same rate of intestinal amino acid absorption as their lean counterparts. Alanine absorption was unchanged by a 24 h starvation period. The whole-body oxidation of the absorbed tracer was lower in the fa/fa rats and was significantly decreased in both lean and obese groups when the animals were submitted to starvation. The incorporation of the 14C-tracer into 14C-lipid was significantly higher in the carcass, skeletal muscle, white adipose tissue and liver of the obese animals, while that of brown adipose tissue was decreased as compared to that of the lean rats. Starvation induced no variation in 14C-lipid incorporation in the lean (+/?) animals while it sharply decreased this parameter in the obese. The incorporation of the tracer into 14C-glycogen and 14C-protein was also increased in the liver of the obese rats while no changes in incorporation into these fractions were observed in skeletal muscle. It is concluded that dietary amino acids significantly contribute to the hyperlipogenesis found in the liver and adipose tissue of the fa/fa rats.     

Medulloblastoma in adulthood: Prognostic factors influencing survival and recurrence

Summary Thirty adult patients presenting with medulloblastoma between 1974 and 1991 were studied and treated at Puerta de Hierro Clinic. After diagnosis, all patients were treated by surgery followed by radiotherapy and eight of them received adjuvant chemotherapy. We have studied the influence of some factors such as age, sex, location of tumour in the cerebellum, amount of surgical resection and histological variants on survival and recurrence of the disease. Only the histological type has a statistically significant influence on survival and recurrence: we have found that patients presenting classic medulloblastoma have a long survival and a long relapse-free interval.     

Visceral leishmaniasis: another HIV-associated opportunistic infection? Report of eight cases and review of the literature

Visceral leishmaniasis (VL) is considered an opportunistic infection in immunocompromised patients. We review the clinical, laboratory, and therapeutic data in 63 patients (eight new cases and 55 cases reported in the literature) with Mediterranean VL (kala azar) and HIV-1 infection to determine whether VL should be considered an opportunistic infection in HIV-infected adults. We conclude that: (1) in areas where both leishmaniasis and HIV-1 infection are endemic, VL may be more frequent among HIV-infected adults; (2) in HIV-infected patients, the clinical picture did not differ significantly from classical kala azar, although it often ran a recurrent course, with resistance to antimonial therapy. We propose the inclusion of VL in the IVC-2 subgroup of the Centers for Disease Control (CDC) clinical classification of HIV-1 infection while prospective and larger studies further define whether there are clinical presentations that could justify adding VL to the list of opportunistic infections indicative of AIDS.     

How do clinicians learn to request permission for autopsies?

A postal survey of 434 clinicians at four local hospitals was undertaken in order to identify the methods by which clinicians learn how to request permission for hospital autopsies and to assess the preferred techniques and timing of relevant communication skills training. The majority of 128 responding clinicians had learnt through personal experience with some assistance from senior colleagues and peers. Few clinicians appeared to have learnt through formal training. The preferred methods for the provision of communication skills training were training in small groups (such as seminars or tutorials) and observation of clinicians at work. The most desirable time for the provision of this training was considered to be between the beginning of the final undergraduate year and the end of the pre-registration house officer year. The communication skills training provided within medical education is in need of improvement. More emphasis should be given to clinical-task- or situation-specific applications such as requesting permission for autopsies.     

Application of ECCLS guidelines to the analysis of Toxoplasma IgG and Rubella IgG using laboratory kits based on the Meia method.

The Meia method is an enzymo-immunoassay involving fluorometric detection, which is used in the Abbott IMx automatic analyzer. The purpose of this report was to analyse the Meia Toxoplasma gondii IgG antibody and Rubella IgG antibody assays, following ECCLS guidelines for the analysis of laboratory kits. The results showed that between-run imprecision for Rubella IgG was close to 15%; for Toxoplasma IgG the percentage was 13%. The mean recovery for Rubella IgG was 104% and 94% for Toxoplasma IgG. The carry-over for Rubella IgG was 0.64% and 0.26% for Toxoplasma IgG which, in both cases, was less than the analytical variability. Both Meia and Elisa showed a linear relationship in the analytical range of the method. Comparing Meia with the Elisa method, constant and proportional differences were found for IgG Rubella and proportional differences for IgG Toxoplasma. The Meia method has many positive analytical features to recommend and it can easily be used in a multidisciplinary laboratory, needing only a small number of serum samples.     

Current data on barotraumatic ear disease with isolated vestibular expression during apnea diving]

The authors have taken an interest in isolated vertiginous symptoms observed from free diving patients. In order to achieve a current bibliographic synthesis, they resume, on basis of 6 cases, the basic principles of the physics theories and the etiopathogenic mechanisms. They try so to help in the understanding of the vestibular clinical signs observed in this successful sport.