Informant ratings of cognitive decline of elderly people: relationship to longitudinal change on cognitive tests

Formal assessment of cognitive decline with cognitive tests can be difficult, requiring either two measurement points or a comparison of 'hold' with 'don't hold' tests. Informant-based assessment provides an alternative approach because informants can adopt a longitudinal perspective and directly rate cognitive change. A study was carried out to assess the validity of informant ratings collected by means of the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE). A community sample of 500 subjects aged 74 or over underwent four cognitive tests on two occasions 3½ years apart. On the second occasion, informants filled out the IQCODE. Subjects rated as having moderate or severe decline were found to have greater change on the cognitive tests. These findings support the validity of informant ratings of cognitive decline.     

Primary Immunodeficiency Diseases in Latin America: The Second Report of the LAGID Registry

This is the second report on the continuing efforts of LAGID to increase the recognition and registration of patients with primary immunodeficiency diseases in 12 Latin American countries: Argentina, Brazil, Chile, Colombia, Costa Rica, Honduras, Mexico, Panama, Paraguay, Peru, Uruguay, and Venezuela. This report reveals that from a total of 3321 patients registered, the most common form of primary immunodeficiency disease was predominantly antibody deficiency (53.2%) with IgA deficiency reported as the most frequent phenotype. This category was followed by 22.6% other well-defined ID syndromes, 9.5% combined T- and B-cell inmunodeficiency, 8.6% phagocytic disorders, 3.3% diseases of immune dysregulation, and 2.8% complement deficiencies. All countries that participated in the first publication in 1998 reported an increase in registered primary immunodeficiency cases, ranging between 10 and 80%. A comparison of the estimated minimal incidence of X-linked agammaglobulinemia, chronic granulomatous disease, and severe combined immunodeficiency between the first report and the present one shows an increase in the reporting of these diseases in all countries. In this report, the estimated minimal incidence of chronic granulomatous disease was between 0.72 and 1.26 cases per 100,000 births in Argentina, Chile, Costa Rica, and Uruguay and the incidence of severe combined immunodeficiency was 1.28 and 3.79 per 100,000 births in Chile and Costa Rica, respectively. However, these diseases are underreported in other participating countries. In addition to a better diagnosis of primary immunodeficiency diseases, more work on improving the registration of patients by each participating country and by countries that have not yet joined LAGID is still needed. Latin American Group for Primary Immunodeficiency Diseases     

Fracture healing following high energy tibial trauma: Ilizarov versus Taylor Spatial Frame

Introduction

The optimal treatment of high energy tibial fractures remains controversial and a challenging orthopaedic problem. The role of external fixators for all these tibial fractures has been shown to be crucial.

Methods

A five-year consecutive series was reviewed retrospectively, identifying two treatment groups: Ilizarov and Taylor Spatial Frame (TSF; Smith & Nephew, Memphis, TN, US). Fracture healing time was the primary outcome measure.

Results

A total of 112 patients (85 Ilizarov, 37 TSF) were identified for the review with a mean age of 45 years. This was higher in women (57 years) than in men (41 years). There was no significant difference between frame types (p=0.83). The median healing time was 163 days in both groups. There was no significant difference in healing time between smokers and non-smokers (180 vs 165 days respectively, p=0.07), open or closed fractures (p=0.13) or age and healing time (Spearman''s r=0.12, p=0.18). There was no incidence of non-union or re-fracture following frame removal in either group.

Conclusions

Despite the assumption of the rigid construct of the TSF, the median time to union was similar to that of the Ilizarov frame and the TSF therefore can play a significant role in complex tibial fractures.     

Chediak-Higashi gene in humans. I. Impairment of natural - killer function

Natural-killer (NK)-cell function was profoundly depressed in donors homozygous for the Chediak-Steinbrinck-Higashi syndrome (C-HS) gene when compared with age- and sex-matched normals. This apparent defect was not simply a result of a delayed response because little cytolysis was evident in kinetics experiments even after 24 h of incubation. NK cells from C-HS donors failed to lyse adherent (MDA, CEM, and Alab) or nonadherent (K562 and Molt-4) tumor cell lines or nontransformed human fetal fibroblasts. Therefore, the apparent C-HS defect was not a result of a shift in target selectivities. In addition, the depressed reactivity did not appear to be a result of suppressor cells or factors because: (a) enriched NK populations (nonadherent lymphocytes bearing receptors for the Fc portion of IgG) from C-HS donors were low in NK-cell function, (b) C-HS mononuclear cells did not inhibit the cytotoxicity of normal cells in coculture experiments, and (c) cells from the C-HS donors remained poorly reactive even after culture for up to 7 d. The nature of the defective NK activity in C-HS patients is not clear but may lie within the lytic mechanism rather than at the level of the recognition structure or population size because the frequency of target-binding cells was normal. In vitro NK activity could be partially restored by interferon treatment. Combined with the results presented in the following paper (4), these observations suggest that the C-HS gene causes a selective immunodeficiency disorder, mainly involving NK cells. This finding, in conjunction with the high incidence of spontaneous possibly malignant, lymphoproliferative disorders in these patients, may have important implications regarding the theory of immune surveillance mediated by NK cells.