Natural killer activity in the experimental privational rickets

To study the 'in vivo' importance of vitamin D on the natural killer (NK) activity, rats were submitted to privational rickets induced by a diet deficient in vitamin D and phosphorus (D-P-). Thirty days after the beginning of treatment the animals showed low body weight, changes in the bone development, and decreased levels of 25-hydroxyvitamin D-3 (25-OH D-3). NK activity, evaluated using a cytotoxicity assay against Cr-51-labeled Yac.1 target cells, was not modified by the rickets-inducing treatment during the first 30 days. Following a long-term treatment (60 days) the rachitic rats (D-P-) exhibited higher NK activity than control animals (D + P +) (P < 0.05). on the other hand, D - P + animals showed higher cytotoxic activity than D - P - and D + P + groups. Feed replacement to the rachitic rats by a complete diet (D - P - /D + P +) led to a partial recuperation of growth, bone development, and 25-OH D-3 scrum. levels. The NK activity was also influenced by vitamin D intake, decreasing after treatment. (C) 2002 Elsevier B.V. B.V. All rights reserved

Mathematical modelling to assess the carrying capacity for multi-species culture within coastal waters

In the context of aquaculture, carrying capacity is generally understood as the standing stock of a particular species at which production is maximised without negatively affecting growth rates. The estimation of carrying capacity for aquaculture is a complex issue. That complexity stems from the many interactions between and among cultivated and non-cultivated species, as well as between those species and their physical and chemical environments. Mathematical models may help to resolve these interactions, by analysing them in a dynamic manner. Previous carrying capacity models have considered the biogeochemical processes that influence growth of cultivated species in great detail. However, physical processes tend to have been addressed very simplistically. Further, most modelling has been for monocultures, despite the increasing importance of multi-species (=polyculture) systems. We present here a two-dimensional coupled physical–biogeochemical model implemented for Sungo Bay, Shandong Province, People’s Republic of China. Sungo Bay is used for extensive polyculture, where bivalve shellfish and kelp are the most important cultivated species. Data collected over 13 years (1983–2000)was available for modelling. Our main objectives were to implement the model, achieving reasonable calibration and validation with independent data sets, for use in estimating the environmental carrying capacity for polyculture of scallops and oysters. Findings indicate that the model successfully reproduces some of the main features of the simulated system. Although requiring some further work to improve predictive capability in parts, predictions clearly indicate that Sungo Bay is being exploited close to the environmental carrying capacity for suspension-feeding shellfish. Comparison of different culture scenarios also indicates that any significant increase in yield will depend largely on a more optimal spatial distribution of the different cultivated species

A functional model of responsive suspension-feeding and growth in bivalve shellfish configured and validated for the scallop Chlamys farreri during culture in China

A dynamic growth model is presented for the suspension-feeding scallop Chlamys farreri. The model is configured and validated for C. farreri cultured in Sungo Bay, China, using functional relations to simulate rapid and sensitive adjustments in feeding and metabolism as observed in response to the highly changeable environment there. Notable novel elements include resolving significant adjustments in the relative processing of living chlorophyll-rich phytoplankton organics, nonphytoplankton organics and the remaining inorganic matter during both differential retention on the gill and selective pre-ingestive rejection within pseudofaeces. We also include a facility to predict the energy content of non-phytoplankton organics. This is significant, for living phytoplankton contributed less than 20% towards suspended particulate organic matter within Sungo Bay. Further, the energy content of non-phytoplankton organics was very much more variable than for phytoplankton organics. Whether using that facility or assuming an average value for the energy content of non-phytoplankton organics, resolution of the relative processing of different particle types allows simulation of how the rates, organic compositions and energy contents of filtered, ingested and deposited matter change in response to differences in seawater temperature, seston availability and seston composition. Dependent relations predict rates of energy absorption, energy expenditure and excretion. By these means, our model replicates dynamic adjustments in feeding and metabolism across full ranges of relevant natural variability, and successfully simulates scallop growth from larvae or seed to harvestable size under different temporal and spatial scenarios of culture. This is an important advance compared with simpler models that do simulate responsive adjustments. Only by modelling the complex set of feedbacks, both positive and negative, whereby suspension feeding shellfish interact with ecosystem processes, can one realistically hope to assess environmental capacities for culture

Brazilian report on primary immunodeficiencies in children: 166 cases studied over a follow-up time of 15 years

One hundred sixty-six cases of primary immunodeficiency diseases (PID) (95 males, 71 females), diagnosed according to WHO criteria, have been registered at the Children's Hospital, University of São Paulo, Brazil. the following frequencies were found: predominantly humoral defects, 60.8% (n = 101); T cell defects, 4.9% (n = 8): combined ID, 9.6% (n = 16); phagocyte disorders, 18.7% (n = 31); and complement deficiencies, 6% (it = 10). IgA deficiency was the most frequent disorder (n = 60), followed by transient hypogammaglobulinemia (n = 14), chronic granulomatous disease (ii = 14), and X-linked agammaglobulinemia (n = 9). in comparison to other (national) reports, we observed higher relative frequencies of phagocyte and complement deficiencies. Recurrent infections were the cause of death in 12.7%. Allergic symptoms were observed in 41%, mainly in IEA-deficient, hypogammaglobulinemic. or hyper-IEE patients, and autoimmune disorders in 5%, predominantly in IgA and complement deficiencies. Five patients suffered from BCG dissemination: two of them died. This is the first Brazilian report on PID over an observation time of 15 years.UNIV São Paulo,DEPT PEDIAT,ALLERGY & IMMUNOL UNIT,São Paulo,BRAZILUNIV São Paulo,DEPT PEDIAT,ALLERGY & IMMUNOPATHOL UNIT,São Paulo,BRAZILINST ADOLFO LUTZ REGISTRO,São Paulo,BRAZILUNIV CAMPINAS,DEPT PEDIAT,CAMPINAS,SP,BRAZILUNIV HEIDELBERG,INST IMMUNOL,D-6900 HEIDELBERG,GERMANYUNIV São Paulo,DEPT IMMUNOL,São Paulo,BRAZILWeb of Scienc

Brazilian report on primary immunodeficiencies in children: 166 cases studied over a follow-up time of 15 years

One hundred sixty-six cases of primary immunodeficiency diseases (PID) (95 males, 71 females), diagnosed according to WHO criteria, have been registered at the Children's Hospital, University of Sao Paulo, Brazil. The following frequencies were found: predominantly humoral defects, 60.8% (n = 101); T cell defects, 4.9% (n = 8): combined ID, 9.6% (n = 16); phagocyte disorders, 18.7% (n = 31); and complement deficiencies, 6% (it = 10). IgA deficiency was the most frequent disorder (n = 60), followed by transient hypogammaglobulinemia (n = 14), chronic granulomatous disease (ii = 14), and X-linked agammaglobulinemia (n = 9). In comparison to other (national) reports, we observed higher relative frequencies of phagocyte and complement deficiencies. Recurrent infections were the cause of death in 12.7%. Allergic symptoms were observed in 41%, mainly in IEA-deficient, hypogammaglobulinemic. or hyper-IEE patients, and autoimmune disorders in 5%, predominantly in IgA and complement deficiencies. Five patients suffered from BCG dissemination: two of them died. This is the first Brazilian report on PID over an observation time of 15 years.17434034