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Introduction: This study aimed to assess the regional and seasonal variations of food consumption in Cambodia. Methods: A cross-sectional food consumption survey was conducted in four different regions in Cambodia involving purposive sampling of 441 and 500 adult subjects aged 25-65 years, respectively. Dietary intake was assessed using 24-hour recall and a food frequency questionnaire. Results: The Cambodian diet typically consists of rice, fish, meat, fruits and vegetables. All subjects consumed rice at least twice a day. Mean daily consumption of cooked rice was 823 g/person, with the men consuming 1022 g/day compared to 712 g/ day for women. In the wet season all subjects consumed 881 g/ day compared to 772 g/ day in the dry season. The mean consumption of vegetables (250 g/day) and fruits (145 g/ day) approximately reached international recommendations (400 g/ day). The highest meat consumption and the lowest fish consumption rates were found in the capital region. The difference in fish and egg consumption between men and women was statistically significant. The Cambodian diet is still not sufficient in milk. The average consumption of alcohol was about 25 g/day. Conclusion: High consumption of rice observed in this study confirms that rice is a staple food in Cambodia as in the other Asian countries. Relatively high meat consumption in the capital could be related to income growth and could indicate the beginning of a nutritional transition from the traditional dietary pattern. Overall, the dietary habits of the Cambodian population have not changed (yet) to adapt to the western style diet. [ABSTRACT FROM AUTHOR]

Guinea-pig erythrocytes that had been exposed to influenza A virus or Vibrio cholerae neuraminidase activated the classical complement pathway in autologous serum. Because all viral particles were eluted from the treated cells, activation was not dependent on anti-viral antibodies or on the particles themselves. After a threshold of 45-55% desialation, had been reached, the relative capacity of treated cells to activate complement increased very rapidly with desialation. Desialation unmasked sites on which natural auto-antibodies of the IgM class were fixed. Antibody fixation on the membrane led to C3b deposition on the cell membrane and activation of the classical complement sequence then cell lysis. The relevance of in vitro lysis of desialated cells to in vivo clearance of these cells is not certain because C4-deficient guinea-pigs were able to eliminate desialated cells from the blood stream as efficiently as did normal guinea-pigs. Nevertheless, membrane desialation occuring during myxovirus infection could lead to autoimmunity and tissue changes, as well as to recovery by eliminating virus-modified cells. [ABSTRACT FROM AUTHOR]

During the ten-year period since the creation of EFSA, two scientific panels of EFSA, the former Scientific Panel on Food Additives, Flavourings, Processing Aids and Materials in Contact with Food (AFC Panel) and the Scientific Panel on Food Additives and Nutrient Sources added to Food (ANS Panel) have been successively responsible for the safety assessment of food additives and nutrient sources added to food. They have successfully addressed a challenging number of applications and re-evaluations while developing specific risk assessment methodologies and guidance for applicants. The achievements of these scientific panels are presented, focusing on: (i) safety assessment of food additives covering new applications and re-evaluation of already authorised food additives; (ii) safety assessment of nutrient sources added to food; and (iii) safety assessment of other substances with a nutritional or physiological effect. The most important developments are highlighted; these include establishment of new guidance for food additive applications and development of more refined exposure assessment methodologies. The future challenges for the ANS Panel are anticipated to be mainly linked to its role in the re-evaluation of the safety of authorised food additives and the assessment of substances other than vitamins and minerals.

EFSA requested the Scientific Committee to develop a guidance document on the use of the weight of evidence approach in scientific assessments for use in all areas under EFSA's remit. The guidance document addresses the use of weight of evidence approaches in scientific assessments using both qualitative and quantitative approaches. Several case studies covering the various areas under EFSA's remit are annexed to the guidance document to illustrate the applicability of the proposed approach. Weight of evidence assessment is defined in this guidance as a process in which evidence is integrated to determine the relative support for possible answers to a question. This document considers the weight of evidence assessment as comprising three basic steps: (1) assembling the evidence into lines of evidence of similar type, (2) weighing the evidence, (3) integrating the evidence. The present document identifies reliability, relevance and consistency as three basic considerations for weighing evidence., (© 2017 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.)

EFSA is committed to assess and communicate the risks occurring in the food and feed chain from farm to fork and to provide other forms of scientific advice. This work, carried out by EFSA since its inception, has resulted in the adoption of thousands of scientific assessments. EFSA is obliged to re-assess past assessments in specific regulatory contexts such as those on food and feed additives, active substances in plant protection products and genetically modified food and feed. In other sectors, the consideration for updating past EFSA scientific assessments is taken on an ad hoc basis mainly depending on specific requests by risk managers or on EFSA self-tasking. If safety is potentially at stake in any area within EFSA's remit, the readiness to update past scientific assessments is important to keep EFSA at the forefront of science and to promote an effective risk assessment. Although this task might be very complex and resource demanding, it is fundamental to EFSA's mission. The present EFSA Scientific Committee opinion deals with scientific motivations and criteria to contribute to the timely updating of EFSA scientific assessments. It is recognised that the decision for updating should be agreed following careful consideration of all the relevant elements by the EFSA management, in collaboration with risk managers and stakeholders. The present opinion addresses the scientific approaches through which it would be possible for EFSA to increase the speed and effectiveness of the acquisition of new data, as well as, to improve the consequent evaluations to assess the relevance and reliability of new data in the context of contributing to the better definition of whether to update past scientific assessments., (© 2017 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.)

Cultured epithelial cells isolated from guinea pig trachea were treated with Vibrio cholerae sialidase. The treatment was not cytotoxic and resulted in membrane desialylation as assessed by measurement of sialic acids released, along with an increased fixation of the galactose-specific lectin peanut agglutinin. After incubation in serum from normal guinea pigs, membrane-bound immunoglobulins were detected using peroxidase-labelled antibodies. Sialidase-treated cells bound significantly more IgM than controls (P < 0.0005), whereas binding of IgG was not significantly different between treated and untreated cells (0.1 < P < 0.375); IgA were never detected. In influenza-infected guinea-pigs, as assessed by reactivity with peanut agglutinin, the tracheal and lung epithelium, as well as alveolar cells were hyposialylated. In these animals, the level of serum IgG autoantibodies capable to bind sialidase treated cultured cells increased, while the level of IgM autoantibodies did not change. These autoantibodies may participate in cellular dysfunctions and modified bronchoreactivity that occur during infection of the respiratory tract by sialidase-producing microorganisms, either through activation of the complement system, or subsequently to their reaction with cells expressing membrane complement and/or Fc receptors.

1. The sialidase activity of human thymocyte was examined by a fluorogenic assay. 2. These studies revealed that human thymocyte sialidase activity is essentially acid-active and membrane-bound since 59.6% and 33% of the total activity was recovered in the lysosome-enriched and microsomal fractions, respectively. 3. A weak activity was also detected in the cytosolic fraction. 4. However, the acidic optimum pH of this soluble sialidase was at variance with the general concept of mammalian soluble sialidases which are known to be optimally active at more neutral pH. 5. This acidic soluble sialidase seems to be a general characteristic of the human T-cell lineage since examination of mature circulating T-cells revealed that they contain a soluble sialidase activity similar to that observed in thymocytes. 6. Analysis of mature and immature thymocyte subpopulation obtained by differential PNA agglutination indicated that this enzymatic system was not altered during the course of thymic maturation. 7. These results suggest that unlike in T-cell activation where changes in the level of sialidase activity were shown to influence the extent of cell surface sialylation and thereby the cell physiology, this enzymatic system seems not to be involved in the fluctuation of cell surface sialic acid content observed during thymic maturation.

Guinea-pig erythrocytes that had been exposed to influenza A virus or Vibrio cholerae neuraminidase activated the classical complement pathway in autologous serum. Because all viral particles were eluted from the treated cells, activation was not dependent on anti-viral antibodies or on the particles themselves. After a threshold of 45-55% desialation, had been reached, the relative capacity of treated cells to activate complement increased very rapidly with desialation. Desialation unmasked sites on which natural auto-antibodies of the IgM class were fixed. Antibody fixation on the membrane led to C3b deposition on the cell membrane and activation of the classical complement sequence then cell lysis. The relevance of in vitro lysis of desialated cells to in vivo clearance of these cells is not certain because C4-deficient guinea-pigs were able to eliminate desialated cells from the blood stream as efficiently as did normal guinea-pigs. Nevertheless, membrane desialation occurring during myxovirus infection could lead to autoimmunity and tissue changes, as well as to recovery by eliminating virus-modified cells.

An enzyme-linked immunosorbent assay (ELISA) using horseradish peroxidase is described for the detection and quantitation of anti-influenza virus antibodies. Compared with complement fixation and hemagglutination inhibition tests, ELISA is far superior with respect to sensitivity and reliability. Non-specific viral inhibitors present in sera do not affect the titer in ELISA. Its sensitivity, close to that of radioimmunoassay permits detection of small amounts of antibodies in pulmonary secretions and supernatants from in vitro spleen cell cultures.

Guinea-pigs were infected intranasally with influenza A Hong Kong 68 (H3N2) virus. Infective particles were re-isolated from lung homogenates up to 3 days after inoculation and indicated local replication. The subsequent lung inflammatory stages were studied by light microscopy, scanning and transmission electron microscopy (TEM). Lung alterations appeared after 24 h and intensified up to 7 days after virus inoculation, progressively decreasing until 3 weeks thereafter. The damage was reversible and complete restoration of structure was obtained within 5 weeks. The lesions commenced with the infiltration of bronchiolar and alveolar walls by polymorphonuclear cells, histiocytes and macrophages. A purulent exudate was seen to occupy the bronchiolar lumen. Cilia disappeared from tracheal and bronchiolar epithelia. Tracheal epithelium desquamated in some animals. TEM examination showed deterioration in type I pneumocytes, an increase in type II pneumocytes and concomitant damage to alveolar capillaries. Alveolar oedema and fibrinous deposits were seen. The pleura presented slight modifications. These results show that infection of guinea-pigs with influenza virus is a useful model for the study of lung pathology associated with a non-lethal respiratory viral infection.

The study of broncho-alveolar lavage harvested from rats intratracheally dusted with chrysotile (0.5 mg), leached chrysotile (0.5 mg), crocidolite (0.5 mg) and quartz (0.5 and 5 mg) indicated: 1. A cytotoxic lysis of alveolar macrophages in relation to phagocytosis of dust particles in the following decreasing order: quartz, crocidolite, chrysotile. 2. Regarding cell intensity and duration while asbestos, even leached chrysotile, gave merely an early and transient response. This cell recruitment concerned mostly PMN leukocytes and at a less extent alveolar macrophage. 3. Cell recruitment was associated with an increased protein and phospholipids alveolar content. The increase of proteins came probably mostly from an inflammatory serum exudation. However, an increase synthesis of complement C3 and phospholipids is not excluded.

Normobarie oxygen exposures momentarily raise by about 20% the haemolytic activity of the guinea pig complement likely by a rise of protein synthesis. About the end of this treatment the complement activity quickly decreases back to its initial value. Hyperbaric oxygen exposure immediately decreases the haemolytic activity. This shift might be result of a release in the serum of cytoplasmic elements bearing an anticomplementary activity or of an inactivation of the complement components involved in the stress reaction appearing in the treated animals. 2 days after the first exposure, during the resting phase, the complement rate increases by about 25% then decreases slowly back to normal.