Prolonged acceptance of skin grafts induced by B cells places regulatory T cells on the histopathology scene

The participation of regulatory T (Treg) cells in B cell-induced T cell tolerance has been claimed in different models. In skin grafts, naive B cells were shown to induce graft tolerance. However, neither the contribution of Treg cells to B cell-induced skin tolerance nor their contribution to the histopathological diagnosis of graft acceptance has been addressed. Here, using male C57BL/6 naive B cells to tolerize female animals, we show that skin graft tolerance is dependent on CD25+ Treg cell activity and independent of B cell-derived IL-10. In fact, B cells from IL-10-deficient mice were able to induce skin graft tolerance while Treg depletion of the host inhibited 100% graft survival. We questioned how Treg cell-mediated tolerance would impact on histopathology. B cell-tolerized skin grafts showed pathological scores as high as a rejected skin from naive, non-tolerized mice due to loss of skin appendages, reduced keratinization and mononuclear cell infiltrate. However, in tolerized mice, 40% of graft infiltrating CD4+ cells were FoxP3+ Treg cells with a high Treg:Teff (effector T cell) ratio (6:1) as compared to non-tolerized mice where Tregs comprise less than 8% of total infiltrating CD4 cells with a Treg:Teff ratio below 1:1. These results render Treg cells an obligatory target for histopathological studies on tissue rejection that may help to diagnose and predict the outcome of a transplanted organ.

Proximate composition and quantification of fatty acids in breaded chicken steak

The aim of this work was to analyze the fatty acid and proximate composition of five brands of breaded chicken steak (A, B, C, D, and E) by accurate chromatographic quantification and to compare the experimental results with food label nutrition facts. The protein values of all brands were in agreement with the Brazilian regulation values, except for that of sample E, which presented the highest lipid content. Thirteen fatty acids were identified in the studied brands and the major ones were oleic acid, linoleic acid, and palmitic acid. The polyunsaturated fatty acid/saturated fatty acid ratios were within the values considered appropriate for human health; however, the high n-6/n-3 ratios found can result in an unbalanced intake of these fat acids. Only samples D and E can be considered trans free according to the regulations. The comparison of the analyses' results and the food label nutrition facts showed little variation in protein values. Nevertheless, most brands underestimated their lipid and energy levels. Brand B and C labels declared "free of trans", but the obteined results showed levels excedding those especified by regulation to be considered trans free values.

Evaluation of the antimicrobial activity of pecan nut [Carya illinoinensis (Wangenh) C. Koch] shell aqueous extract on minimally processed lettuce leaves

Abstract Pecan nutshell is a residue from food industry that has potential to be used as biopreservative in foods. The objective of this study was to evaluate the antimicrobial activity of pecan nutshell aqueous extract in vitro and its effectiveness to inhibit spoilage microorganisms on lettuce leaves. The results indicate that the aqueous extract presents inhibitory activity against important foodborne pathogenic bacteria such as Listeria monocytogenes, Salmonella Enteritidis, Staphylococcus aureus, Bacillus cereus, Aeromonas hydrophila and Pseudomonas aeruginosa. Antimicrobial activity was not observed against Corynebacterium fimi, Clostridium perfringens, Escherichia coli, and the phytopathogenic fungi tested. When applied onto lettuce leaves, pecan nutshell extract reduced the counts of mesophilic and psychrotrophic bacteria in 2 and 4 log CFU/g, respectively, during storage of leafy for 5 days at refrigeration temperature (5 °C). The extract was not effective to inhibit yeast on lettuce leaves. Thus, the aqueous extract of pecan shell showed great potential to be used as a natural preservative in foods, acting mainly in the inhibition of spoilage and pathogenic bacteria.

A systematic observation of hostile aggression in Junior B hockey

Aggressive behaviours within the sport of hockey appear to be increasing in both prevalence and consequence (Biasca, Wirth, & Tegner, 2002). Accordingly, this area of inquiry is currently garnering a considerable amount of attention from society and academics alike. The problem however, is that our current understanding of these behaviours has been deemed both incomplete and unreliable. The inconsistencies inherent within this body of knowledge have been traced back to a variety of methodological shortcomings. The purpose of this investigation was to assess hostile aggression using a more ecologically valid and comprehensive research design. Ten Junior B hockey games were tapped and subsequently coded by three independent observers, using a validated operational list. Two hundred and fifty-nine behaviours were extrapolated and examined according to the score differential, period, position of the aggressor, status of the aggressor's team, and whether the aggressor was a member of the home or visiting team. It was concluded that the frequency of aggressive behaviours significantly differed according to the score differential, and status of the aggressor's team (p < .01). However, these hostile acts did not differ according the aggressor's position, period, and the home versus away status of the aggressor's team (p > .01). It was also determined that the majority of aggressive acts (69.1 1%) across these ten games went unsanctioned. This highlights the profound influence that "positive misses" have on penalty measures of aggression, while concurrently highlighting the ecological validity present with observational designs. Consequently, by assessing aggressive behaviour in a more inclusive and ecologically valid manner, a more accurate picture of the frequency and distribution of hostile aggression may be provided.

Persons who served more than six months in the War of 1812 : letter from the Secretary of War, transmitting in compliance with a resolution of the House calling for a statement of the number of officers, non-commissioned officers, privates, &c., who served for a period of six months and upwards in the War of 1812.--

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Stereoselective synthesis of 5-substituted pyrrolo[1,2-c]imidazol-3-ones. Access to aldosterone synthase inhibitors and chiral precatalysts

Compounds containing the pyrrolidine moiety are key substructures of compounds with biological activity and organocatalysts. In particular, annulated chiral pyrrolidines with alpha stereogenic centers have aldostereone synthase inhibition activity. In addition, 5-substituted pyrroloimidazol(in)ium salts precursors to N-heterocyclic carbene (NHC) precatalysts are rare due to a lack of convenient synthetic routes to access them. In this thesis is described a rapid synthesis of NHC precursors and a possible route to 5-substituted pyrroloimidazole biologically active compounds. The method involves the preparation of chiral saturated and achiral unsaturated pyrrolo[I,2- c]imidazol-3-ones from N-Cbz-protected t-Butyl proline carboxamide. The resulting starting materials may be used to prepare the target chiral annulated imidazol(in)ium products by a two-step sequence involving first stereoselective lithiation-substitution, followed by POCh induced salt formation.

Cabinet Card of Young Woman Photographed by N. C. Shorey, of Toronto [n.d.]

An unidentified African Canadian young woman is the subject of this cabinet card portrait photograph by N. C. Shorey, of Toronto, Ontario. The photo is undated but believed to be taken in the late 1890s. The photographer's stamp, with his name and address, appears in the gold lettering at the bottom of the card. The young woman in the photograph could possibly be a relative of the Sloman - Bell family, who resided in the London and St. Catharines areas. This cabinet card was in the possession of Iris Sloman Bell, of St. Catharines, Ontario. The Sloman - Bell family relatives are descended from former Black slaves from the United States.N. C. Shorey is listed as a photographer in Toronto, Ont. from 1892 - 1900. Source: Phillips, Glen C. The Ontario photographers list (1851-1900). Sarnia: Iron Gate Publishing Co., 1990. "Cabinet card photographs were first introduced in 1866. They were initially employed for landscapes rather than portraitures. Cabinet cards replaced Carte de visite photographs as the popular mode of photography. Cabinet cards became the standard for photographic portraits in 1870. Cabinet cards experienced their peak in popularity in the 1880's. Cabinet cards were still being produced in the United States until the early 1900's and continued to be produced in Europe even longer. The best way to describe a cabinet card is that it is a thin photograph that is mounted on a card that measures 4 1/4″ by 6 1/2″. Cabinet cards frequently have artistic logos and information on the bottom or the reverse of the card which advertised the photographer or the photography studio's services." Source: http://cabinetcardgallery.wordpress.com/category/cabinet-card-history/

Synthesis of 3', 5'-cyclic diguanylic acid (c-di-GMP) analogues

In the past few years, interest in signaling networks involving 3ʹ, 5ʹ -cyclic diguanylic acid (c-di-GMP) has increased dramatically. Evidence started to emerge that connects c-di-GMP to the regulation of a range of biological processes in bacteria, such as bacterial biofilm formation, virulence, extracellular polysaccharide synthesis, however, much remains to be explored in the signaling pathways that involve this secondary messenger. This molecule has also been shown to be a very powerful immunostimulating agent and potent mucosal vaccine adjuvant.

The effects of administration of a nuclear factor kappa-B inhibitor on pulmonary endothelial dysfunction after cardiopulmonary bypass: impact on oxygenation and hemodynamics and development of therapeutic and preventive modalities in a porcine model

Introduction: La circulation extracorporelle (CEC) peut entraîner une dysfonction endothéliale pulmonaire et l’hypertension pulmonaire. Le SN50 agit au niveau de la signalisation cellulaire pour prévenir ces réactions à la CEC et pourrait renverser la dysfonction endothéliale pulmonaire post-CEC sans effets néfastes sur l’hémodynamie. Méthodes: Quatre groups de porcs ont reçu un parmi quatre traîtements avant de subir 90 minutes de CEC et 60 minutes de reperfusion: (1) milrinone nébulisé; (2) sildenafil nébulisé; (3) placebo nébulisé; et (4) SN-50 intraveineux. Un monitoring hémodynamique invasif a été utilisé. La réactivité vasculaire des artères pulmonaires de deuxième ordre a été évaluée face à l’acétylcholine et la bradykinine. Résultats: Le sildénafil produit une augmentation significative de la pression de l’artère pulmonaire (PAP) moyenne à 60 minutes de reperfusion par rapport au début de la chirurgie. Les relaxations dépendantes de l’endothélium face à la bradykinine étaient meilleurs dans les groupes milrinone et SN-50 et surtout dans le groupe sildénafil par rapport au groupe placébo. Le SN-50 produisait de moins bonnes relaxations dépendantes de l’endothélium face à l’acétylcholine que les autres traitements incluant placébo. Conclusion: Le sildénafil prévient mieux la dysfonction endothéliale pulmonaire que les autres traitements. Les bénéfices du SN-50 sont possiblement sous-estimés vu que la dose n’a pas pu être ajustée à la durée de CEC. Le sildenafil inhalé mérite une étude plus importante chez l’humain et le SN-50 dans un model de CEC animal.

Pulsed Photoacoustic Determination of Absolute Fluorescent Quantum Yield of the Laser Dye Rhodamine B

Pulsed photoacoustic technique which is found to be a very convenient and accurate method, is used for the determination of absolute fluorescence quantum yield of laser dye rhodamine B. Concentration and power dependence of quantum yield of rhodamine B in methanol for excitation at 532 nm is reported here. Results show that a rapid decrease in quantum yield as the concentration is increased and finally it reaches the limit corresponding to fluorescence quenching.