Assay for lipid peroxides in animal tissues by thiobarbituric acid reaction

Summary: Staphylococcus aureus is an important cause of skin and soft-tissue infections (SSTIs), endovascular infections, pneumonia, septic arthritis, endocarditis, osteomyelitis, foreign-body infections, and sepsis. Methicillin-resistant S. aureus (MRSA) isolates were once confined largely to hospitals, other health care environments, and patients frequenting these facilities. Since the mid-1990s, however, there has been an explosion in the number of MRSA infections reported in populations lacking risk factors for exposure to the health care system. This increase in the incidence of MRSA infection has been associated with the recognition of new MRSA clones known as community-associated MRSA (CA-MRSA). CA-MRSA strains differ from the older, health care-associated MRSA strains; they infect a different group of patients, they cause different clinical syndromes, they differ in antimicrobial susceptibility patterns, they spread rapidly among healthy people in the community, and they frequently cause infections in health care environments as well. This review details what is known about the epidemiology of CA-MRSA strains and the clinical spectrum of infectious syndromes associated with them that ranges from a commensal state to severe, overwhelming infection. It also addresses the therapy of these infections and strategies for their prevention.

Community-associated methicillin-resistant Staphylococcus aureus: epidemiology and clinical consequences of an emerging epidemic.

The terms 'antioxidant', 'oxidative stress' and 'oxidative damage' are widely used but rarely defined. This brief review attempts to define them and to examine the ways in which oxidative stress and oxidative damage can affect cell behaviour both in vivo and in cell culture, using cancer as an example.

Biochemistry of oxidative stress

Serotonin, tryptophan metabolism and the brain-gut-microbiome axis.

Bacillus cereus is widespread in nature and frequently isolated from soil and growing plants, but it is also well adapted for growth in the intestinal tract of insects and mammals. From these habitats it is easily spread to foods, where it may cause an emetic or a diarrhoeal type of food-associated illness that is becoming increasingly important in the industrialized world. The emetic disease is a food intoxication caused by cereulide, a small ring-formed dodecadepsipeptide. Similar to the virulence determinants that distinguish Bacillus thuringiensis and Bacillus anthracis from B. cereus, the genetic determinants of cereulide are plasmid-borne. The diarrhoeal syndrome of B. cereus is an infection caused by vegetative cells, ingested as viable cells or spores, thought to produce protein enterotoxins in the small intestine. Three pore-forming cytotoxins have been associated with diarrhoeal disease: haemolysin BL (Hbl), nonhaemolytic enterotoxin (Nhe) and cytotoxin K. Hbl and Nhe are homologous three-component toxins, which appear to be related to the monooligomeric toxin cytolysin A found in Escherichia coli. This review will focus on the toxins associated with foodborne diseases frequently caused by B. cereus. The disease characteristics are described, and recent findings regarding the associated toxins are discussed, as well as the present knowledge on virulence regulation.

From soil to gut: Bacillus cereus and its food poisoning toxins

Immune responses and gene expression in white shrimp, Litopenaeus vannamei, induced by Lactobacillus plantarum

γ-Aminobutyric acid (GABA), a hypotensive agent, and monacolin K, a cholesterol-lowering drug, can be produced by Monascus spp. Under optimal culture conditions, the products of fermentation using Monascus spp. may serve as a multi-functional dietary supplement and can prevent heart disease. In this study, Monascus purpureus CCRC 31615, the strain with the highest amount of monacolin K, was identified from 16 strains using solid fermentation. Its GABA productivity was particularly high. Addition of sodium nitrate during solid-state fermentation of M. purpureus CCRC 31615 improved the productivity of monacolin K and GABA to 378 mg/kg and 1,267.6 mg/kg, respectively. GABA productivity increased further to 1,493.6 mg/kg when dipotassium hydrophosphate was added to the medium.

Production of the secondary metabolites gamma-aminobutyric acid and monacolin K by Monascus.

BACKGROUND: Immunomodulation by probiotic microorganisms has become a topic of increasing interest in food microbiology. Polysaccharides are broadly used in the food industry as gelling, thickening, stabilizing, or emulsifying agents. Some probiotics such as lactic acid bacteria also produce exopolysaccharides that stimulate macrophage production of cytokines. The aim of this study was to characterize the effects of exopolysaccharides of Lactobacillus paracasei subsp. paracasei NTU 101 (101EP) and Lactobacillus plantarum NTU 102 (102EP) exopolysaccharides on antioxidant activity and immunomodulation in vitro.

RESULTS: The sugar composition (including arabinose, galactose, glucose, fructose, mannose, and maltose) of 101EP and 102EP was quantified by high-performance anion-exchange chromatography. Cytokine production (including IL-6, TNF-α, and IL-1β) was induced by 101EP and 102EP in Raw 264.7 in a dose-dependent manner (5-500 µg mL−1). 101EP and 102EP also demonstrated potential antioxidant properties (1,1-diphenyl-2-picrylhydrazyl radical scavenging activity, chelation of ferrous ions, inhibition of linoleic acid peroxidation, and reducing power) in vitro.

CONCLUSION: 101EP and 102EP stimulate cell proliferation and may be useful as a mild immune modulator of macrophages. Copyright © 2011 Society of Chemical Industry

Immunomodulatory and antioxidant potential of Lactobacillus exopolysaccharides.

Probiotics have a number of beneficial health effects in humans and animals, such as reducing lactose intolerance symptoms and enhancing the bioavailability of nutrients. Probiotics help regulate intestinal microflora and immunomodulatory properties. Probiotics also decrease the prevalence of allergies in susceptible individuals, inhibit the inflammatory responses in the gut, and have antagonistic effects against intestinal and food-borne pathogens. Bacteria typically colonize the intestinal tract first and then reinforce the host defense systems by inducing generalized mucosal immune responses, including modulation of DC/NK interaction, a balanced T-helper cell response, self-limited inflammatory response, and the secretion of polymeric IgA. A lot of reports showed that lactic acid bacteria (LAB) as Lactobacillus and Bifidobacterium and their fermented products are effective at enhancing innate and adaptive immunity, prevent gastric mucosal lesion development, alleviate allergies, and put up defense against intestinal pathogen infection. In this review paper, we compared the influence of immunomodulatory effects on the function and efficacy of lactobacillus products with different strains. We also discuss the beneficial effects of several LAB strain and its derivative products for human immunity and related diseases.

Tzu-Ming Pan

Papers

Immune responses and gene expression in white shrimp, Litopenaeus vannamei, induced by Lactobacillus plantarum

Production of the secondary metabolites gamma-aminobutyric acid and monacolin K by Monascus.

Immunomodulatory and antioxidant potential of Lactobacillus exopolysaccharides.

The immunomodulatory effects of lactic acid bacteria for improving immune functions and benefits

Exopolysaccharide activities from probiotic bifidobacterium: Immunomodulatory effects (on J774A.1 macrophages) and antimicrobial properties.