A total of 291 unvaccinated sheep from Brucella melitensis-infected flocks were examined for delayed-type hypersensitivity (DTH) responses with Brucellergene commercial allergen and with cold saline extract and cytosol from rough B. melitensis 115, and their sera were tested in the rose bengal test (RBT), complement fixation test (CFT), and enzyme-linked immunosorbent assay (ELISA) with lipopolysaccharide. DTH reactions were maximal after 72 h, with no intensity differences among allergens, inoculation sites (eyelid and tail), and doses tested. There were no differences in the results recorded by visual inspection and palpation of inoculation sites, by measuring skin thickness with a caliper, or by microscopic examination of samples taken at necropsy. Six days after DTH testing, anergy was observed in 100%Yo of the animals, and 100%v reactivity was recovered only after 24 days. All animals were necropsied, and thorough bacteriological searches were performed. The sensitivities found with the 140 animals from which B. melitensis was isolated were ELISA, 100%o; DTH, 97.1%; RBT, 92.1%; and CFT, 88.6%. Those results put into question the value of RBT and CFT as screening and confirmatory tests for sheep brucellosis and at least indicate that their standardization should be modified. For 151 tested sheep from which B. melitensis was not isolated, the percentages of positive animals were ELISA, 100%o; DTH, 94.0%; RBT, 57.6%; and CFT, 53.6%. All tests were negative for 100 tested sheep from Brucella-free flocks. The different results of bacteriological and immunological tests suggest the usefulness of developing indirect tests able to distinguish truly infected animals from those that have developed an immunological response.

A lipid extract with a composition similar to that of myelin was used to prepare liposomes and proteoliposomes containing the Folch-Lees proteolipid apoprotein. Freeze-fracture replicas of the proteoliposomes were prepared to demonstrate the presence of intramembrane protein particles in the fracture faces of the lipid bilayer. Experiments with 45CaCl2 showed that a steady calcium movement occurs across liposomal membranes, approaching equilibrium between intra- and extravesicular spaces. The most significant finding was that Mg-ATP, ATP analogues, and other nucleotides depressed significantly the calcium fluxes in proteoliposomes, having no effect on liposomes that lacked the proteolipid protein. It is suggested that this intrinsic protein, interacting with nucleotides and endogenous lipids, could be involved in the regulation of calcium levels in myelin by means of a conformational change mechanism. These observations could lead to implications concerning the pathophysiology of myelin.

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BackgroundCardiovascular events (CVE) are an increasing cause of morbi-mortality for HIV patients. The antiretroviral therapy (ART), persistent immune activation, and life style are factors that can increase CVE for such patients. We performed a case-control study to evaluate the role of coinfections and immune markers associated with CVE.MethodsWe included patients under ART, with undetectable plasma viral load ≥12 months. Patients presenting any condition of risk for CVE were considered cases, and those without CVE risk conditions were controls. History of viral infections (Epstein–Barr virus, hepatitis C virus, hepatitis B virus, and cytomegalovirus), exposure to antiretroviral drugs, time since HIV diagnosis/under ART, and life style (demographics, weight, smoking, alcohol, and illicit drug use) were assessed. CD4/CD8 nadir and current counts, nadir and current CD4/CD8 ratio, immune activation markers (CD4CD38HLADR, CD8CD38HLADR), and serum levels of eight cytokines [IL-2, IL-4, IL-6, IL-10, tumoral necrosis factor-alpha (TNF-α), interferon gamma, macrophage inflammatory proteins 1 alpha, and interferon-inducing protein (IP-10)] were measured.ResultsTwo-thirds of patients were males. Cases (N = 106) were older (52.8 vs 49.5 years, p = 0.002), had higher levels of creatinine (0.97 vs 0.87 mg/dL, p = 0.002) and IL-6 (0.67 vs 0.52 pg/mL, p = 0.04) than controls (N = 114). There was no difference between groups regarding frequency of CD4CD39HLADR+ or CD8CD38HLADR+ cells. We found a significant correlation (all patients) between increased frequency of CD4CD38HLADR+ cells and levels of IP-10 (r = 0.171, p = 0.02) and TNF-α (r = 0.187, p = 0.01). Levels of IL-6 (r = 0.235, p = 0.02), TNF-α (r = 0.267, p = 0.01), and IP-10 (r = 0.205, p = 0.04) were correlated with CD4CD38HLADR+ cells, in controls. Higher frequency of CD4CD38HLADR+ cells was also correlated with levels of IP-10 (r = 0.271, p = 0.04) in patients presenting with arterial hypertension. Frequency of CD4CD38HLADR+ cells was negatively correlated with levels of IL-2 (r = −0.639, p = 0.01) and IL-6 (r = −0.0561, p = 0.03) in patients with hypercholesterolemia. No association was detected between viral infections or smoking/alcohol use and immune activation markers.ConclusionOur results indicate IL-6 levels are associated with increased CV risk. Activated CD4+ T cells were associated with increased levels of proinflammatory cytokines.

Breast cancer remains a leading cause of morbidity and mortality worldwide yet methods for early detection remain elusive. We describe the discovery and validation of biochemical signatures measured by mass spectrometry, performed upon blood samples from patients and controls that accurately identify (>95%) the presence of clinical breast cancer. Targeted quantitative MS/MS conducted upon 1225 individuals, including patients with breast and other cancers, normal controls as well as individuals with a variety of metabolic disorders provide a biochemical phenotype that accurately identifies the presence of breast cancer and predicts response and survival following the administration of neoadjuvant chemotherapy. The metabolic changes identified are consistent with inborn-like errors of metabolism and define a continuum from normal controls to elevated risk to invasive breast cancer. Similar results were observed in other adenocarcinomas but were not found in squamous cell cancers or hematologic neoplasms. The findings describe a new early detection platform for breast cancer and support a role for pre-existing, inborn-like errors of metabolism in the process of breast carcinogenesis that may also extend to other glandular malignancies.Statement of Significance: Findings provide a powerful tool for early detection and the assessment of prognosis in breast cancer and define a novel concept of breast carcinogenesis that characterizes malignant transformation as the clinical manifestation of underlying metabolic insufficiencies.

A method of preparing a total lipid extract (TLE), free of protein, by extracting brain white matter with tetrahydrofuran is presented. The optimal conditions of extraction were found to be 50 ml of THF per gram of lyophilized tissue, though fresh tissue can also be used if larger volumes of solvent are employed. The method allowed, in a short time and in a single step, a yield of TLE of 50% on a dry weight basis. Its analytical characterization revealed a qualitative and quantitative composition very similar to the lipid composition of CNS myelin, including all the phospholipid and galactolipid species, cholesterol and gangliosides, but it contained only traces (0.1%) of protein. TLE has been used to prepare liposomes, either multilamellar (MLVs) or unilamellar (LUVs, SUVs), characterized by freeze ‐fracture electron microscopy. A multilayered, heterogeneous population of liposomes is observed in the MLVs preparation. When these samples were submitted to a freezing and thawing procedure the resulting liposomes were single‐walled, and their intravesicular volume was increased. They were quite impermeable to the mono‐valent cation 86Rb+ and, by contrast rather permeable to 45Ca+ +. Their complex lipid composition, together with their permeability properties and their response to ionophores, make them very useful to study protein‐lipid interactions occurring within the myelin membrane as well as the functional properties of myelin proteins in reconstitution experiments.

: The major proteins of myelin have classically been extracted in organic solvents. Here we investigated some of the characteristics of brain myelin solubilization in aqueous detergent solutions. At comparable molar concentrations, two nonionic detergents, i.e., octyl glucoside and Lubrol PX, proved relatively better myelin solubilizers than the detergents related to the bile salts, i.e., cholate and CHAPS. The two former detergents solubilized more protein than lipid and the two latter ones more lipid than protein from myelin membranes. All four detergents solubilized the phospholipid more efficiently than the cholesterol component of myelin. The detergent concentrations required for myelin solubilization were reduced substantially if the temperature and the salt concentration of the media were increased. As much as 3 mg of lyophilized myelin (about 1 mg of protein) were solubilized readily per milliliter of a solution containing 30 mM octyl glucoside and 0.1 M sodium sulfate in 0.1 M sodium phosphate buffer, pH 6.7. Each of the detergents studied, including the above four, sodium dodecyl sulfate (SDS), Triton X‐100, and Zwittergent 3–14, had its own advantages and drawbacks as myelin protein extractors. The nonionic amphiphiles and CHAPS left a small residue mainly composed of proteins of the Wolfgram fraction, as revealed by SDS‐polyacrylamide gel electrophoresis. Octyl glucoside was preferred, given its versatility as solubilizer, ultraviolet transparency, and high critical micellar concentration. Observations on possible difficulties that may be encountered are also included.

The number of solvents capable of dissolving myelin and proteolipid protein (PLP) and of being used as a mobile phase for the separation of myelin proteins by reversed-phase high-performance liquid chromatography (RP-HPLC) is very limited. In a thorough study, we found that aqueous tetrahydrofuran (THF) fulfilled such a requirement. The maximal amount of protein extracted corresponded to a THF/water ratio of 4:1 v/v and a polarity index of 5.16. This mixture dissolved a purified PLP preparation completely, 60% of proteins from fresh myelin, and 20% of white matter total proteins. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) of those extracts, followed by densitometric analysis, showed that the amount and type of proteins dissolved depended on the polarity (i.e., the content of water) of the solvent mixture used. This selective effect was greater for basic protein in myelin preparations. Crude extracts highly enriched in basic protein can be prepared. In addition, the solvent system THF/water proved to be very useful as a mobile phase in RP-HPLC for separating myelin proteins. Using a C3 column and a linear gradient from 30% to 100% THF in water, both containing 0.1% trifluoroacetic acid (TFA), we separated completely the three main protein fractions of central nervous system (CNS) myelin in a short period of time. The high solubility power of THF/water mixtures prolonged greatly the life of the column.