IgG Protease Mac/IdeS Is Not Essential for Phagocyte Resistance or Mouse Virulence of M1T1 Group a Streptococcus.

IgG Protease Mac/IdeS Is Not Essential for Phagocyte Resistance or Mouse Virulence of M1T1 Group A Streptococcus.

MBio. 2013; 4(4):
Okumura CY, Anderson EL, Döhrmann S, Tran DN, Olson J, von Pawel-Rammingen U, Nizet V

ABSTRACT The Mac/IdeS protein of group A Streptococcus (GAS) is a secreted cysteine protease with cleavage specificity for IgG and is highly expressed in the GAS serotype M1T1 clone, which is the serotype most frequently isolated from patients with life-threatening invasive infections. While studies of Mac/IdeS with recombinant protein have shown that the protein can potentially prevent opsonophagocytosis of GAS by neutrophils, the role of the protein in immune evasion as physiologically produced by the living organism has not been studied. Here we examined the contribution of Mac/IdeS to invasive GAS disease by generating a mutant lacking Mac/IdeS in the hyperinvasive M1T1 background. While Mac/IdeS was highly expressed and proteolytically active in the hyperinvasive strain, elimination of the bacterial protease did not significantly influence GAS phagocytic uptake, oxidative-burst induction, cathelicidin sensitivity, resistance to neutrophil or macrophage killing, or pathogenicity in pre- or postimmune mouse infectious challenges. We conclude that in the highly virulent M1T1 background, Mac/IdeS is not essential for either phagocyte resistance or virulence. Given the conservation of Mac/IdeS and homologues across GAS strains, it is possible that Mac/IdeS serves another important function in GAS ecology or contributes to virulence in other strain backgrounds. IMPORTANCE Group A Streptococcus (GAS) causes human infections ranging from strep throat to life-threatening conditions such as flesh-eating disease and toxic shock syndrome. Common disease-associated clones of GAS can cause both mild and severe infections because of a characteristic mutation and subsequent change in the expression of several genes that develops under host immune selection. One of these genes encodes Mac/IdeS, a protease that has been shown to cleave antibodies important to the immune defense system. In this study, we found that while Mac/IdeS is highly expressed in hypervirulent GAS, it does not significantly contribute to the ability of the bacteria to survive white blood cell killing or produce invasive infection in the mouse. These data underscore the importance of correlating studies on virulence factor function with physiologic expression levels and the complexity of streptococcal pathogenesis and contribute to our overall understanding of how GAS causes disease. HubMed – eating

Changing Dietary Habits in Persons Living with Type 2 Diabetes.

J Nutr Educ Behav. 2013 Jul 27;
Castro-Sánchez AE, Avila-Ortíz MN

To describe changes in eating behavior and analyze subjects’ perceptions regarding a diabetes diet.Qualitative study was conducted with 45 semistructured interviews; 21 men and 24 women who had been diagnosed with type 2 diabetes were included. Sample size was determined by theoretical sampling. Responses were grouped into codes that described concepts, themes, and subthemes.Three phases were identified: initial, accommodation-adaptation, and crisis. The most significant difficulties were controlling appetite increase, replacing animal fats with vegetable fats and meat with legumes and vegetables, and eating with others.Eating behavior changes over time, with several stages, when a person lives with type 2 diabetes. Strict adherence to diet is only temporary and short-term. Further research is needed to help ill persons after they receive their first diet prescription. HubMed – eating

Association between Serum Vitamin D Status and Metabolic Syndrome in Korean Young Men.

Med Sci Sports Exerc. 2013 Jul 29;
Ha CD, Han TK, Lee SH, Cho JK, Kang HS

The study examined the relations of serum vitamin D levels to body fatness, cardiorespiratory fitness (CRF), and metabolic risk factors in young adults in Korea.Between 2007 and 2009, 799 young men completed a health examination. Body fatness, CRF based on a maximal treadmill exercise test, and measurements of metabolic risk factors were measured in study participants. Participants were classified by serum vitamin D levels as deficient (20 ng•mL) and by CRF as unfit (lowest 20%) and fit (remaining 80%) based on age-standardized distribution of VO2max values in this study population. Body fatness, CRF, and metabolic risk factors were evaluated according to serum vitamin D classification. A clustered metabolic risk score was computed by summing standardized scores for waist circumference, resting blood pressures, triacylglycerols, the inverse of high-density lipoprotein cholesterol, glucose, and insulin.Linear decreases in body fatness and metabolic risk factors were observed, as was a linear increase for CRF across incremental vitamin D categories. A linear decrease was found in the clustered metabolic risk score across incremental vitamin D categories. Compared to the fit group (referent), the unfit group had significantly higher risks for serum vitamin D inadequacy before and after adjusting for age, smoking, and body fatness parameters.The findings of the study suggest that increasing vitamin D intake, eating a healthy diet, and getting enough outdoor physical activity should be promoted as non-pharmacologic means to improve CRF and prevent a clustering of metabolic risk factors in young adults. HubMed – eating

[Effects of delayed first feeding on growth and survival of Hucho taimen larvae].

Ying Yong Sheng Tai Xue Bao. 2013 Apr; 24(4): 1125-30
Zhang YQ, Yin JS, Du J, Zhang Y, Tong GX

This paper studied the effects of delaying first breeding Hucho taimen larvae for different days on the larvae growth, survival, and body size. Five treatments were installed, i. e. , feeding begins on the first eating day (control, S0) and on the 9th, 12th, 15th, and 18th days after the first eating day (S1 -S4) at 10.4-14.9 degree C, respectively. By the end of the experiment (36-day), the growth rate and initial feeding rate in S1 was higher than that in S0, and the overall mortality rate in S1 was lower, but the body size and mass in S1and S0 had no significant difference. Compared with S0, S2 had higher growth rate, initial feeding rate, total mortality, and self-mutilation mortality, the body mass was significantly lower, but the body size had less difference. S3 had higher first feeding rate, body size, total mortality, and self-mutilation mortality, but significantly lower body mass than S0, whereas the growth rate had less difference. In S4, the growth rate and body mass were lower, and the total mortality and self-mutilation mortality were higher than those in S0. It was suggested that under the same conditions, delaying first feeding for 9 days would induce H. taimen larvae presenting “completely compensatory growth”, and this feeding way could be applied for the culture of H. taimen larvae in their initial feeding period. HubMed – eating

Yoga therapy for eating disorders
Watch it with headphones for better listening. Therapist Lauren Manasse-Latham, LICSW interviews yoga therapist Divya Jyoti (DJ) for her course in eating dis…