Stimulation of genetic resistance to marrow grafts in mice by interferon-alpha/beta

Lethally irradiated mice were infused with syngeneic, H-2 allogeneic, parental strain, or H-2 heterozygous bone marrow cells. They were injected daily with rabbit anti-mouse interferons (IFN)-alpha/beta or gamma or with IFN-alpha/beta. The growth of donor-derived cells was judged 5 days later by measuring splenic incorporation of 5-iodo-2'-deoxyuridine-125I into DNA. Antibodies to IFN-alpha/beta, but not to IFN-gamma, weakened genetic (both hybrid and allogeneic) resistance to marrow cell grafts. IFN-alpha/beta stimulated hybrid and allogeneic resistance, the latter even in genetically "poor responder" mice. Mice pretreated with silica, which weakens genetic resistance, were stimulated by IFN-alpha/beta to resist incompatible marrow cell grafts; however, IFN-alpha/beta failed to reverse the effects of antiasialo GM1 serum on marrow graft rejection. IFN-alpha/beta did not inhibit the growth of syngeneic marrow cells and did not stimulate resistance to H-2 heterozygous bone marrow cells. We propose that genetic resistance occurs in two discrete steps. In the first step, hemopoietic histocompatibility (Hh) antigens are recognized by one host cell type, and this recognition leads to IFN-alpha/beta secretion by a silica-sensitive cell. In the second step, asialo GM1-positive natural killer cells stimulated by IFN-alpha/beta recognize Hh antigens on marrow stem cells and cause rejection. The defects in resistance observed in genetically poor responder mice and in mice treated with silica appear to involve the first step in recognition. The lack of rejection of H-2 heterozygous (Hh-) marrow cells by parental strain mice injected with IFN-alpha/beta indicated that specific Hh recognition is critical in the second step of genetic resistance.     

Evaluation of superoxide dismutase and glutathione peroxidase enzymes and their cofactors in Egyptian children with Down's syndrome

The present work investigated the activity of Cu/Zn superoxide dismutase enzyme (SOD) in red blood cells and glutathione peroxidase enzyme (GPx) in whole blood by spectrophotometric methods. Plasma levels of the cofactors copper and zinc and whole-blood selenium were evaluated using atomic absorption spectrophotometer. The study included a population of 18 Down's syndrome (DS) patients with complete trisomy 21 (group 1), translocations (group 2), and mosaicism (group 3), and their 15 matched controls. The purpose of this work was to study the gene dosage effect of SOD and its consequence on GPx enzyme and the various cofactors, and to find out correlations with developmental fields. Our results showed that in the population with complete trisomy 21 and translocations, SOD and GPx activities were increased, whereas in cases with mosaicism, the enzymes activities were within normal limits. Plasma copper concentrations were increased, whereas whole-blood selenium concentrations were significantly decreased in the three DS groups. Plasma zinc levels were within normal in all patients. We concluded that changes in trace elements and enzyme activities were not related to age or sex. Also, there was no correlation between the enzyme levels and the developmental activities. Our results are useful tools for identifying nutritional status and guiding antioxidant intervention.     

Alkaline Phosphatase Activity in Skin, as Shown by Staining En Bloc1

A modification of Gomori's method for alkaline phosphatase was applied to 5-7 mm cubes of fresh, unfixed human skin. Exposure to the substrate of buffered Na-β·glycerophosphate was varied from 8-36 hr, to the 2% Co(NO₃)₃, 2-12 hr; and to ammonium sulfide (containing approximately 1% NH₃), 1-2 hr. Optimum timing for these treatments were found to be 24, 4 and 1 hr, respectively. After staining, blocks were embedded in paraffin and serial sections were made. In such small blocks, the staining was uniform throughout the block. Alkaline phosphatase activity was seen in the walls of the subepidermal and periappendageal capillaries, as well as in the eccrine sweat glands, and did not differ from that seen in stained frozen sections. In particular, there was no loss of specificity and no diffusion of the enzyme.     

Aroma Profile of Two Populations of Salvia verbenaca Collected from Two Bio‐Geographical Zones from Jordan

The aroma emitted from the different organs of two Salvia verbenaca L. populations from Jordan were extracted by Solid Phase Micro‐Extraction (SPME) and then analyzed by GC/MS. The emission profile of the stem, leaf and sepal samples from the Mediterranean zone (Al‐Salt) was dominated by monoterpene hydrocarbons (68.0 %, 33.7 %, and 42.2 %, respectively). The emission profile of flowering parts including pre‐flowering buds, fully expanded flowers and petals was dominated by oxygenated monoterpenes (58.6 %, 59.3 % and 87.1 %, respectively). The major constituent detected in these organs was trans‐sabinene hydrate acetate (range 14.5 %–87.0 %). On the other hand, samples collected from Irano‐Turanian zone showed different emission patterns. While the stems, leaves and petal emissions were dominated by sesquiterpene hydrocarbons (54.9 %, 76.8 % and 52.6 %, respectively), monoterpene hydrocarbons dominated the emission profiles of the pre‐flowering buds (75.1 %) and fully expanded flowers (73.6 %). Petals emissions were characterized by high concentrations of oxygenated monoterpenes (58.8 %). Notably, trans‐sabinene hydrate dominated most organs emissions except for leaves (range 20.0 %–58.8 %). Principle Component Analysis (PCA) and Cluster Analysis (CA) revealed two different clusters related to the two different geographical zones. The current investigation revealed two ecotypes of S. verbenaca that could result in two different chemotypes. Trans‐sabinene hydrate acetate and trans‐sabinene hydrate are suggested compounds for identifying these two chemotypes.