CS exposure--clinical effects and management.
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The number of people exposed to CS spray presenting to accident and emergency departments is on the increase. Its effects, though usually minor and short lived, involve several systems and can occasionally be life threatening. It is therefore important that staff are able to manage these patients and know when and how to protect themselves and others from further contamination. (+info)
Experimental infection of calves with bovine viral diarrhea virus genotype II (NY-93).
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To ascertain the virulence of bovine viral diarrhea virus (BVDV) genotype II, isolate NY-93 was inoculated intranasally into 3 calves, 2 of which were treated with a synthetic glucocorticoid prior to and after virus inoculation. Anorexia, fever (up to 42 C), dyspnea, and hemorrhagic diarrhea developed 6 days after intranasal inoculation with BVDV NY-93. The condition of all calves deteriorated further until the end of the study on day 14 postinoculation. The most significant postmortem macroscopic changes in all calves were limited to the gastrointestinal tract and consisted of moderate to severe congestion of the mucosa with multifocal hemorrhages. Microscopic lesions found in the gastrointestinal tract were similar to those observed in mucosal disease, including degeneration and necrosis of crypt epithelium and necrosis of lymphoid tissue throughout the ileum, colon, and rectum. The basal stratum of the epithelium of tongue, esophagus, and rumen had scattered individual necrotic cells. Spleen and lymph nodes had lymphocytolysis and severe lymphoid depletion. Severe acute fibrinous bronchopneumonia was present in dexamethasone-treated calves. Abundant viral antigen was detected by immunohistochemistry in the squamous epithelium of tongue, esophagus, and forestomachs. BVDV antigen was prominent in cells of the media of small arteries and endothelial cells. The presence of infectious virus in tissues correlated with an absence of circulating neutralizing antibodies. These findings highlight the potential of BVDV genotype II to cause severe disease in normal and stressed cattle. (+info)
Genetic analysis of the bone morphogenetic protein-related gene, gbb, identifies multiple requirements during Drosophila development.
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We have isolated mutations in the Drosophila melanogaster gene glass bottom boat (gbb), which encodes a TGF-beta signaling molecule (formerly referred to as 60A) with highest sequence similarity to members of the bone morphogenetic protein (BMP) subgroup including vertebrate BMPs 5-8. Genetic analysis of both null and hypomorphic gbb alleles indicates that the gene is required in many developmental processes, including embryonic midgut morphogenesis, patterning of the larval cuticle, fat body morphology, and development and patterning of the imaginal discs. In the embryonic midgut, we show that gbb is required for the formation of the anterior constriction and for maintenance of the homeotic gene Antennapedia in the visceral mesoderm. In addition, we show a requirement for gbb in the anterior and posterior cells of the underlying endoderm and in the formation and extension of the gastric caecae. gbb is required in all the imaginal discs for proper disc growth and for specification of veins in the wing and of macrochaete in the notum. Significantly, some of these tissues have been shown to also require the Drosophila BMP2/4 homolog decapentaplegic (dpp), while others do not. These results indicate that signaling by both gbb and dpp may contribute to the development of some tissues, while in others, gbb may signal independently of dpp. (+info)
High dietary lipid levels enhance digestive tract maturation and improve dicentrarchus labrax larval development.
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This study was designed to determine the nutritional lipid requirement of seabass larvae and to understand the effects of dietary fat concentration on their digestive tract maturation. Seabass (Dicentrarchus labrax) larvae were fed, from d 15 to 38 of life, one of five isonitrogenous compound diets with different lipid levels, ranging from 10 to 30 g/100 g. The higher the lipid level, the greater the growth and survival of the larvae (P < 0.05). The lipolytic enzymes assayed, lipase and phospholipase A2, were stimulated by the increase in their respective dietary substrates, triglycerides and phospholipids, in 38-d-old larvae (P < 0.05). Nevertheless, a plateau in the activity of these two lipolytic enzymes was observed from 20% dietary lipids onwards. The similar mRNA levels of phospholipase A2 in the three groups fed the highest lipid levels suggested that the maximal synthesis level of lipolytic enzyme was reached at 20% dietary fat. Pancreatic secretion of trypsin and amylase were positively affected by the dietary lipid level; a possible involvement of a cholecystokinin-releasing factor is discussed. Diets containing >20% lipids led to the increase in activities of brush border membrane enzymes to the detriment of a cytosolic enzyme in enterocytes, leucine-alanine (Leu-Ala) peptidase. This enzymatic change reveals the earlier maturation of enterocytes in larva groups fed high lipid levels. (+info)
Limited effect of refined carbohydrate dietary supplementation on colonization of the gastrointestinal tract of healthy subjects by Candida albicans.
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BACKGROUND: Infections due to Candida albicans occur readily in situations in which ample glucose is available. In mice, dietary refined carbohydrate supplementation leads to higher rates of Candida growth in the gastrointestinal tract and favors mucosal invasion. OBJECTIVE: The modulating properties of dietary carbohydrate supplementation on colonization of the human gastrointestinal tract by C. albicans were evaluated. DESIGN: A 2-step study was conducted in 28 healthy volunteers. First, we determined the subjects' habitual uptake of refined carbohydrates and correlated these data with the C. albicans blastoconidia concentration in the mouth washes and feces of subjects with no intervention. Second, we compared C. albicans counts in the specimens before, during, and after a high-sugar diet. RESULTS: No correlation between C. albicans counts in the specimens and the habitual uptake of refined carbohydrates was observed. A high-sugar diet did not increase the frequency of C. albicans-positive samples, the number of subjects positive for C. albicans in the mouth washes, or the concentration of candidal blastoconidia in the samples of the 28 subjects. However, in selected subjects with elevated counts of oral C. albicans, we observed an increase in fecal C. albicans counts in response to the diet. CONCLUSIONS: The effect of adding a high amount of refined carbohydrates to the diet of healthy human subjects has a limited influence on Candida colonization. Follow-up studies should define whether selected patient groups might benefit from dietary restriction of refined carbohydrates. (+info)
Interleukin-2 (IL-2) amplifies immune stimuli and influences B cell differentiation. IL-2-deficient mice spontaneously develop intestinal inflammation if raised under specific pathogen-free (SPF) conditions. We quantitatively determined the aggressiveness and kinetics of gastrointestinal and hepatic inflammation in the presence or absence of viable bacteria in IL-2-deficient mice. Breeding colonies were maintained under SPF and germfree (GF) conditions. Intestinal tissues, serum, and mesenteric lymph nodes were obtained from mice at different ages for blind histological scoring, immunoglobulin measurements, mucosal T cell infiltration, and cytokine secretion. GF IL-2 -/- mice developed mild, focal, and nonlethal intestinal inflammation with delayed onset, whereas the more aggressive inflammation in SPF IL-2 -/- mice led to their death between 28 and 32 wk. Periportal hepatic inflammation was equal in the presence or absence of bacterial colonization. Intestinal immunoglobulin secretion decreased significantly by 13 wk of age in IL-2 -/- mice in both GF and SPF environments. In contrast to other genetically engineered rodents, IL-2 -/- mice develop mild focal gastrointestinal and active portal tract inflammation in the absence of viable bacteria. (+info)
Relationship of nimesulide safety to its pharmacokinetics: assessment of adverse reactions.
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Non-steroidal anti-inflammatory drugs (NSAIDs) are among the most widely used drugs and their use is frequently associated with severe or even serious adverse events, which increase morbidity and mortality. The increase of toxic effects, primarily of the digestive system, due to treatment with NSAIDs, underlines a need for safer NSAIDs. Nimesulide (4-nitro-2-phenoxymethanesulphonanilide) is a chemically unique anti-inflammatory agent in that it has a higher pKa (6.5) than conventional acidic NSAIDs and it is one of the newer class of NSAIDs that are selective for cyclooxygenase-2. Nimesulide also has additional activities, among them effects on production/action of oxy-radicals and other components of neutrophil activation that may contribute to the spectrum of its anti-inflammatory activity as well as potentially reducing the likelihood of gastrointestinal ulcerogenicity. An analysis was performed of the safety data of nimesulide collected in clinical studies and from those reported spontaneously worldwide in the post-marketing phase. The results show that nimesulide is associated with a relatively low occurrence of adverse drug reactions especially in the gastrointestinal tract while those in the liver are within or below the general incidence with other NSAIDs. (+info)
Gastrointestinal toxicity of non-steroidal anti-inflammatory drugs: the effect of nimesulide compared with naproxen on the human gastrointestinal tract.
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This overview includes theories and evaluation of non-steroidal anti-inflammatory drug (NSAID)-induced gastrointestinal toxicity. Factors in damage include microvascular aspects, neutrophil recruitment, mucosal prostaglandins, gastrointestinal secretions and bacteria. We have proposed an extensive simplified framework that includes an important local initiating effect which may involve NSAID accumulation, interaction with surface phospholipids, events that alter cellular ATP, and local/systemic effects of cyclooxygenase (COX) inhibition. COX-2-selective drugs are desirable not only because they spare COX-1 and so avoid gastrointestinal toxicity, but also because COX-2-selective agents are only weakly acidic and therefore avoid substantial accumulation in the gastric mucosa. Short-term endoscopy studies of NSAIDs are important initially to evaluate human gastroduodenal tolerability. They show that injury increases with the amount of NSAIDs even though the lowest therapeutic doses inhibit gastric COX almost completely, and that the more-acidic NSAIDs tend to cause greater gastric damage. Long-term endoscopy studies involve NSAID ingestion for at least 3 months. A main question is the extent to which the ulcers seen cause symptoms, substantial bleeding and/or perforation. Measurement of serious outcomes is thought by many to be the best assessment of gastrointestinal safety, but studies find marked variations even with the same drug. Damage to the small intestine by NSAIDs is even more frequent than to the upper gastrointestinal tract, but is difficult to evaluate. Conventional acidic NSAIDs increase the permeability of human small intestine, probably by a non-prostaglandin mechanism, but nimesulide does not do so, possibly because of its very weak acidity. (+info)