Research Note: Validation of a new differentiation approach using the commercial ASAPTM media to detect the Salmonella 441/014 vaccine strain.

Vaccination is one of the most important control tools to reduce Salmonella in poultry production. In order for a live vaccine to be licensed for field use it should be provided with the detection methods to differentiate it from field strains. This paper aims to describe the validation of an alternative method for the differentiation of the Salmonella 441/014 vaccine strain from field strains, using a chromogenic Media, ASAP from bioMérieux. The ASAP-based differentiation method was compared with already authorized methods, namely the Anicon SE Kylt PCR DIVA 1 assay and Ceva S-Check Salmonella differentiation kit, following the ISO 16140-6:2019 validation method guidelines. A Generalised Linear Model was fitted to the data to determine the inclusivity and exclusivity of differentiation methods (PCR Kylt vs. S-Check vs. ASAPTM). Statistical differences were based on a P-value level of < 0.05 (SPSS Inc., Chicago, IL). In this study, we show that the ASAP media was able to differentiate Salmonella Enteritidis vaccine strains from field strains, obtaining 100% agreement between the three differentiation assays. This differentiation approach is quicker, easier to deploy and cheaper as compared to alternative methods.

Mannose receptor ligand-positive cells express the metalloprotease decysin in the B cell follicle.

Decysin, a gene encoding a disintegrin metalloprotease, is transcribed in human dendritic cells (DC) and germinal centers (GC). We have cloned its murine homologue and show that it is processed by the endoprotease furin before secretion of the catalytic domain. We have defined the cell types that express decysin in mouse spleen in the course of an immune response to T cell-dependent Ags. Like in humans, decysin is transcribed by activated CD11c(+) DC that enter the T cell zone from the marginal zone (MZ). In the GC, decysin is expressed by follicular DC and tingible body macrophages. In addition, a MZ cell population expresses decysin and appears to migrate into the B cell follicle. The majority of these follicle-homing cells express the mannose receptor ligand, a marker for the macrophage-like MZ metallophils. The follicle-homing cells are M-CSF dependent, as they are absent in op/op mice that lack functional M-CSF. This suggests that mannose receptor ligand(+) MZ metallophils differentiate into cells that migrate from the MZ into the B cell follicle. Decysin represents the first marker for this previously unrecognized cell population of the mouse spleen, which may represent a precursor for GCDC and may be specialized in the transport of unprocessed Ag from the MZ into developing GC.

Weak TCR stimulation induces a calcium signal that triggers IL-4 synthesis, stronger TCR stimulation induces MAP kinases that control IFN-gamma production.

Th1 and Th2 cells produce different cytokines and have distinct functions. Th1/Th2 cell differentiation is influenced, among other factors, by the nature of TCR-MHC interactions. However, how the TCR transduces a signal resulting in IFN-gamma or IL-4 production is a matter of debate. For example, some authors reported a loss of calcium signaling pathway in Th2 cells. We used a T cell hybridoma producing IL-4 upon weak TCR stimulation and both IL-4 and IFN-gamma for strong TCR engagement as a model to study how TCR signaling pathways are differentially activated in both conditions of stimulation and how this influences the production of cytokines. We show that: (1) the calcium response is identical following weak and strong TCR stimulation; (2) mitogen-activated protein kinase(MAPK) activation is a gradual phenomenon depending upon the strength of TCR activation; (3) a calcium response, even weak, triggers IL-4 expression; (4) IFN-gamma synthesis requires not only a calcium response but also MAPK activation. The MAPK pathway is dispensable for IL-4 production, although it amplifies IL-4 synthesis upon strong TCR stimulation; (5) TCR-induced IL-4 production also depends on calcium signaling in Th2 cells, while IFN-gamma synthesis is dependent, in addition, on MAPK activation in Th1 cells.

Gold is a T cell polyclonal activator in BN and LEW rats but favors IL-4 expression only in autoimmune prone BN rats.

Gold salts are beneficial in the treatment of rheumatoid arthritis but may induce immune-mediated disorders in predisposed patients. Gold salts induce Th2-dependent autoimmunity in Brown-Norway (BN) rats but not in Lewis (LEW) rats. The aim of this study was to define molecular targets of gold salts and to approach why LEW rats are resistant. Gold salts act on early steps of transduction in T cells from BN and LEW rats since they trigger tyrosine phosphorylation of numerous proteins including p56(lck) and a calcium signal which results in IL-4 and IFN-gamma expression by BN and LEW T cells. However, the IL-4 response was favored in BN spleen cells in vitro and in vivo. IFN-gamma, produced in part by CD8(+) cells, contributes to the resistance of LEW rats since gold salt-injected LEW rats receiving anti-CD8 or anti-IFN-gamma mAb displayed the parameters characteristics of gold salt-induced Th2 autoimmunity although to a lesser extent than in BN rats. Gold salts transduce a signal in BN and LEW spleen cells resulting in IL-4 and IFN-gamma gene transcription with a preferential IL-4 response in BN rats, a Th2-prone strain, while IFN-gamma contributes to the resistance of LEW rats.

[Calcium-dependent pathways involved in the production of cytokines in lymphocytes]. / Les voies dépendantes du calcium impliquées dans la production de cytokines dans les lymphocytes.

CD4+ T lymphocytes are divided in Th1 cells producing IFN gamma and Th2 cells that synthetize IL-4. This paper describes signaling pathways activated following T cell receptor (TCR) engagement and emphasizes differences that can account for differential cytokine production. This paper focuses on a new signaling pathway involved in IL-4 synthesis. This pathway couples the TCR to PKC that controls a calcium entry through dihydropyridine sensitive calcium channels. The calcium response is sufficient to initiate IL-4 gene transcription. Differing from that of IL-4, IFN gamma gene expression always requires MAP-kinase activation in addition to a calcium signal.

Determination of potato glycoalkaloids using a liposome immunomigration, liquid-phase competition immunoassay.

Polyclonal anti-solanine antibodies were raised and used in the assembly of a liposome immunomigration, liquid-phase competition strip immunoassay. In this format, a similar cross-reactivity was observed between the glycoalkaloids alpha-solanine and alpha-chaconine. The strip assay was implemented to quantitate total glycoalkaloids (TGA) from potatoes. Recoveries in spiked potato samples using the strip assay and water:acetic acid:sodium bisulfite extracting solvent were in the range of 84-111%. The values of the TGA quantitations by the strip assay as compared with those obtained by HPLC, in nonspiked tubers coming from cloned potato samples donated by potato breeders, were equivalent and highly correlated (r(2) = 0.91). The strip assay proved advantageous over HPLC for extra-laboratory measurements such as the rapid identification of samples that should be rejected due to an elevated TGA content.

Soluble Fc gamma receptors: interaction with ligands and biological consequences.

Soluble Fc gamma receptors are produced by cleavage of the membrane receptors or by alternative splicing. They are found in biologic fluids. After a brief description of the structure and mode of production of soluble Fc gamma R, we address the question of ligands and function of the soluble Fc gamma R by using recombinant molecules and transgenic animals. We show that soluble Fc gamma R are not only IgG-binding factors which interfere with, and block, Fc-dependent immune reactions but also molecules that interact, in vitro, with non-Ig-ligands such as CR3 and CR4 and are trigger or regulate immune functions via these receptors.

Relationships between serum lipids, platelet membrane fatty acid composition and platelet aggregation in type 2 diabetes mellitus.

In order to gain further insight into the mechanism of platelet dysfunction frequently reported in diabetes we investigated circulating fatty acids, lipid composition of platelet membrane and platelet function in Type 2 diabetic patients. In these subjects, percentages of C16 : 1n-7 and C18 : 1n-9 in serum phospholipid fraction and of C16 : 1n-7 in serum cholesterol ester fraction were decreased. Moreover, the content of C20 : 4n-6 in serum cholesterol esters was altered in Type 2 diabetic subjects: C18 : 0 and C20 : 3n-6 were increased but C20 : 4n-6 content was similar to controls. Aggregation in vitro did not differ from controls but aggregation in vivo was increased in Type 2 diabetic subjects. No correlation was observed between metabolic parameters -i.e., HbA1, blood glucose, serum triglycerides and total cholesterol, circulating fatty acids and fatty acid content of platelet membrane. A negative linear correlation was found between aggregation in vivo and C20 : 4n-6 content of platelet membrane. Moreover, a U shaped relationship was observed between platelet aggregation in vitro and C20 : 4n-6 content of platelet membrane suggesting that C20 : 4n-6 level should be tightly controlled otherwise platelet hyperreactivity may occur. These results indicate that despite a normal mean C20 : 4n-6 content in the platelet membrane, regulation of C20 : 4n-6 metabolism is less strictly controlled in Type 2 diabetes mellitus and confirm the importance of arachidonic acid platelet content in the regulation of platelet aggregability.

HDL-cholesterol and breast cancer: a joint study in northern Italy and southern France.

The goal of the present study is to evaluate HDL-cholesterol (HDL-C) as a marker of breast cancer (BC) risk. It is based on several epidemiological and biological studies and is justified by the rising incidence of breast cancer throughout the world. A hospital-based study on host-related risk factors and breast cancer, conducted with similar methods in northern Italy and southern France, provided the biological data, the information on the established BC risk factors and on nutrition for 307 cases and 329 controls. This data set allowed for a thorough analysis of the relationship of HDL-C with established risk factors for BC and also of its association with BC at the time of diagnosis. Most of our findings on HDL-C determinants in the control sample are comparable to previous studies. The BC risk factors associated with reproductive life correlate with HDL-C levels: the protective factors are associated with a lower level of HDL-C and inversely. The same is true for nutritional factors such as alcohol. For these determinants, the trend is similar for cases and controls, and HDL-C level appears to be related to oestrogen metabolism. Thus it may be considered as a marker of BC risk. Our results indicate that high HDL-C levels should be especially checked in women aged > or = 60 years, or in premenopausal women presenting a low BMI, or in postmenopausal women with an early menopause.

[Quality evaluation of a dehydrated product based on potato (Solanum tuberosum), lupin (Lupinus mutabilis) and eggs]. / Evaluación de la calidad de un producto deshidratado en base a papa (Solanum tuberosum), lupino (Lupinus mutabilis) y huevo.

After a mathematical evaluation of 20 mixtures containing different proportions of potato (P), lupin (L) and whole egg (E) on dry basis and kept the latter component in a constant amount of 6 per cent, a mixture of 60:34:6 (P:L:E) was chosen for a further experimental work at a lab level because of his better nutritional value for the pre-school children feeding. When an eighteen percent suspension of the mixture mentioned above was dehydrated in a drum drier an adecuate yield of flakes was obtained with an appropriate water absorption. The sensory evaluation test of the dehydrated product as a sauce indicated a higher acceptance than purées. On the other hand, during a 90 days period storage test of the product as flakes, it did not show microbiological problems, although after 45 days rancidity appeared in the dehydrated product.

The role of diet history and biologic assays in the study of "diet and breast cancer".

Nutritional factors related to breast cancer were investigated by means of a hospital-based case-control study in Milan (Italy) and Montpellier (France). Liposoluble vitamins, cholesterol and triglycerides were measured in blood samples taken from interviewed subjects (319 cases and 344 controls). In addition serum zinc and copper was assessed in the Italian samples and serum fatty acids and malonyl-di-aldehyde in the French samples. A significant difference was found between cases and controls in total fat and cholesterol intake in both populations, and in saturated fatty acid and mono-unsaturated fatty acid consumption in the French samples. No difference emerged in liposoluble vitamin consumption in both populations nor in zinc and copper consumption in the Italian samples. A statistically significant higher serum level of cholesterol and plasma level of vitamin E was observed in cases compared to controls in both populations. The difference in plasma vitamin E was confirmed after adjustment on total cholesterol and triglycerides. Similarly, zinc serum level was higher in Italian cases than in Italian controls, while malonyl-di-aldehyde was lower in French cases than French controls. A multivariate analysis was performed after classification of cases and controls according to quantile distribution of controls. Nutrient consumption and relevant blood markers were directly or partially correlated in both populations. All known risk factors plus age, serum total cholesterol and triglycerides were used as covariates. The odds ratio values for the highest quantiles are: Dietary cholesterol, OR = 1.9 (1.1-3.4); total dietary lipids, OR = 1.9 (1.0-3.4); plasma vitamin E, OR = 4.2 (1.9-9.0); serum zinc, OR = 12.2 (5.4-27.7); serum malonyl-di-aldehyde, OR = 0.56 (0.33-0.97).

Relationship between vitamin E and polyunsaturated fatty acids in breast cancer. Nutritional and metabolic aspects.

Intake of vitamin E, total lipids, total cholesterol, and fatty acids were analyzed with the blood levels of vitamin E, total cholesterol, triglycerides, and the serum distribution of fatty acids in a hospital-based population of 120 patients and 109 controls. In regard to nutritional intake, the only significant differences involve saturated and monounsaturated fatty acid consumption, which is more elevated in postmenopausal patients than in postmenopausal controls. Vitamin E and total cholesterol blood levels are significantly higher in patients than in controls, where the difference is that vitamin E is independent from cholesterol level in premenopausal women only. Fatty acid serum distribution is comparable in both samples, with the exception of arachidonic acid, which is significantly lower in premenopausal patients than in premenopausal controls. Two multivariate regression analyses of the plasma vitamin E levels of patients and controls were done with menopausal status and nutrients as independent variables for the first analysis, and with menopausal status and all blood analytes for the second one. The regression coefficients for total cholesterol and triglycerides are statistically significant for both samples, whereas a positive association between vitamin E plasma level and sunflower oil consumption and between vitamin E plasma level and serum linoleic acid distribution is significant for patients only. Furthermore, the multiple regression shows that, when adjusted for analyte variables, plasma vitamin E levels are higher in premenopausal than in postmenopausal patients. In addition, plasma lipid peroxidation, evaluated by malondialdehyde measurement, is shown to be significantly lower in patients than in controls. Malondialdehyde level is associated with a significant lower odds ratio (OR) after multivariate tertile analysis (OR for the highest tertile: 0.51; 95% CI: 0.29-0.89). Together, these findings are consistent with a picture of lower lipid peroxidation in patients than in controls.

[Sexually-transmissible anorectal diseases]. / Maladies anorectales sexuellement transmissibles.

Several anorectal diseases are described. Most are sexually transmitted (gay bowel syndrome or heterosexual transmission). The clinical aspect of nearly all of them is similar. Thus, the diagnosis usually cannot be done on clinical grounds alone: one has to request the help of the laboratory. Amebiasis, giardiasis, chancroid and donovanosis are frequent in Africa but rare in our countries, except in male homosexuals. Shigellosis, salmonellosis, pediculosis, scabies and campylobacter infections are seen in male homosexuals because of orofecal contacts. Condylomata acuminata are frequent in our country. The typical clinical aspect leads to an easy diagnosis. Electrocoagulation is the treatment of choice. Anorectal gonococcal are also frequent in our country, both homosexually and heterosexually transmitted. The clinical aspect suggests the diagnosis, but this must be confirmed by the laboratory.

Failure to achieve tight control of plasma cholesterol and apolipoprotein B with intraperitoneal insulin infusion in type 1 diabetes.

The best route of insulin administration by infusion pumps remains a subject of controversy. For that reason plasma lipids and apolipoproteins were compared in three groups of nine patients who had been treated for several months or years with conventional treatment (group I), continuous subcutaneous insulin infusion (CSII, group II) or continuous intraperitoneal insulin infusion (CPII, group III). Plasma cholesterol and apolipoprotein B remained increased on CPII compared with CSII even when similar satisfactory or even tight diabetic control was achieved with both techniques. This study suggests that cholesterol and perhaps apolipoprotein B biosynthesis by the liver is increased in patients treated with CPII compared to those treated with CSII.

[Paralytic ileus secondary to podophyllin poisoning]. / Ileus paralytique secondaire à une intoxication à la podophylline.

The authors report a case of general and local poisoning after erroneous intravaginal administration of podophyllin for warts. The clinical course mainly showed a 10 day paralytic ileus, vaginal and urethral lesions and a severe peripheral neurological illness: paresthesia, dysesthesia and ataxia. The authors stress the potential toxicity of podophyllin and recommend great caution in using this product.

Liposoluble vitamins and lipid parameters in breast cancer. A joint study in northern Italy and southern France.

The relationship between breast cancer, liposoluble vitamins, cholesterol and triglycerides was investigated by means of a hospital-based case-control study conducted at Milan (Italy) and Montpellier (France). These parameters were measured in blood samples taken from 319 cases and 344 controls. The interview included an evaluation of dietary intake of liposoluble vitamins. No difference emerged in liposoluble vitamin consumption, whereas a statistically significantly higher serum level of cholesterol and plasma level of vitamin E existed in cases compared to controls. The difference in plasma vitamin E was confirmed after adjustment for total cholesterol and triglycerides. In contrast, vitamin A variations appear to follow triglyceride trends. A multivariate analysis of the vitamin E plasma level was performed after classification of cases and controls according to quintile distribution of controls. All known risk factors plus age, serum total cholesterol and triglycerides were used as covariates. The odds ratio value for the highest quintile of plasma vitamin E is: 4.2 (1.9-9.0).

Plasma lipid fatty acids and platelet function during continuous subcutaneous insulin infusion in type I diabetes.

Eleven insulin-dependent diabetics exhibiting a fair but less than ideal diabetic control (HbA1 = 10.0 +/- 0.6%) were submitted in a random order to two 6 week-study periods of: continuous subcutaneous insulin infusion (CSII) and optimized conventional insulin therapy. Plasma lipids, fatty acids in plasma lipids and platelet function were estimated at baseline and at the end of each study period. Declines in HbA1 were observed at the end of either CSII or conventional period compared with baseline, but the differences were only significant under CSII (P less than 0.02). Plasma lipids and apoproteins remained unchanged at the end of the two study periods compared with baseline. Both CSII and optimized conventional treatment were followed by a significant increase of arachidonate in plasma lipids. A deterioration of the platelet function estimated from ADP or epinephrine-induced platelet aggregation and TxB2 generation by platelets was found under optimized conventional treatment while the platelet function appears to be normal at baseline and under CSII. These data indicate that slight but not sufficient improvements of diabetic control can result in deterioration of the platelet function. It seems that these deleterious effects are mediated through an increased production of arachidonate and in turn of TxB2.