Interaction of radiation-generated radicals with myoglobin in aqueous solution. III. Effects of oxygen and catalase on the product distribution in solutions of ferrimyoglobin containing N2O

The gamma-radiolysis of aqueous solutions of ferrimyoglobin in the presence of N2O at pH 7.3 has been examined as a function of added catalase and oxygen. Changes in the nature of the heme group have been monitored by visible absorption spectrophotometry and analysed quantitatively by a multiple wavelength method based on Beer's Law. Simple chemical analyses have been used to confirm qualitative identification of the product derivatives. As observed previously, the ferriheme is reduced by indirect globin-mediated action initiated by OH/H. The yield of reduced product decreases as [O2] increases. Conversion to ferrimyoglobin through the participation of H2O2 derived from irradiated water and from protein-mediated processes in oxygenated solution, is eliminated by the presence of catalase. Formation of a hemichrome form of ferrimyoglobin is apparent at higher doses in the presence of O2. These results demonstrate that oxygen plays an important role in controlling the nature and extent of redox that manifests ultimately on the heme group of ferrimyoglobin as a result of the initial interaction of OH/H.     

Cervical intraepithelial neoplasia and associated condylomatous lesions. A preliminary report on 4,764 women from Northern Israel

During the period spanning the years 1973 to 1981, 4,764 women visited the Gynecology Out-Patient Clinics and Colposcopy Unit of the Nahariyya Hospital to be examined colposcopically and cytologically (and histologically whenever indicated) for precancerous and cancerous lesions of the cervix. Of these women, 2,614 (55%) were referred because of symptoms of cervical pathology and 2,150 (45%) for other (prophylactic) reasons. The subdivision of all women according to their demographic backgrounds afforded a comparison of the findings in Israeli-born Jewesses with those of foreign-born Jewesses and non-Jewish females living in the same geographic area of the Western Galilee district of Israel. Despite the low prevalence of cervical cancer in Jewesses throughout the world, the preliminary report of our pilot study demonstrated that the percentage rates of all degrees of dysplasia/cervical intraepithelial neoplasia (CIN I, II and III) of the uterine cervix of Israeli-born Jewesses was 5.4% in patients with cervical pathology and 3.24% in noncervical-pathology patients. These rates were the highest recorded for any of the demographic groups: 2.06% and 0.33%, respectively, in Moslem women; 1.23% in Christian women with cervical pathology; 2.38% and 1.78%, respectively, in European/American-born Jewesses; and 1.63% and 0.48%, respectively, in Asian/African-born Jewesses. The highest proportion of CIN lesions occurred in the 15- to 30-year-old age groups. Of 100 CIN lesions found in all patients, 45 were cytohistologically associated with the cells of condylomatous lesions. Of 36 patients in whom cervical squamous-cell carcinoma lesions were detected, 18 (50%) were staged (FIGO) as carcinoma in situ (stage 0); the remainder were in stages IA, IB, IIA and IIB, with none in stages III or IV.     

The mast cells of the mammalian central nervous system. IX. Development of the mast cells in the brain of the young rat

There are four potentially granular or frankly granular cells within the connective tissue compartment of the mammalian central nervous system, whether this is part of the surface leptomeninges or the leptomeningeal sleeves around parenchymal blood vessels larger than capillaries. These are: Cells that behave like macrophages, part of the mononuclear phagocyte system of the body; they are granular to varying degrees (containing lysosomes). Brown-pigmented granular cells which are mainly located on the surface but are also seen for varying distances along blood vessels as they pass inside the CNS of pigmented animals. Mast cells (MCs) which are granular and located especially prominently in surface leptomeninges of young mammals, and, in adults, are restricted to special parts of the CNS. Granular cells, referred to by me as neurolipomastocytoid cells (NLMs), are numerous, ubiquitously distributed, and seem to have morphological features in common with those of both MCs and macrophages. The exact identity of these NLMs still needs to established. One approach was to study the development of all three non-pigmented cells in the immature brain of the albino rat, especially at the ultrastructural level. This communication represents the findings regarding the MCs. The MCs appear to arise from a small mononuclear cell and to go through maturation stages identical to those described by others for MCs outside the CNS. The greatly flattened adjacent leptomeningeal cells are an easily identifiable entity especially due to their peculiar glycogen content in the young.     

Conserved Nodulation Genes in Rhizobium meliloti and Rhizobium trifolii

Plasmids which contained wild-type or mutated Rhizobium meliloti nodulation (nod) genes were introduced into Nod⁻R. trifolii mutants ANU453 and ANU851 and tested for their ability to nodulate clover. Cloned wild-type and mutated R. meliloti nod gene segments restored ANU851 to Nod⁺, with the exception of nodD mutants. Similarly, wild-type and mutant R. meliloti nod genes complemented ANU453 to Nod⁺, except for nodCII mutants. Thus, ANU851 identifies the equivalent of the R. meliloti nodD genes, and ANU453 specifies the equivalent of the R. meliloti nodCII genes. In addition, cloned wild-type R. trifolii nod genes were introduced into seven R. meliloti Nod⁻ mutants. All seven mutants were restored to Nod⁺ on alfalfa. Our results indicate that these genes represent common nodulation functions and argue for an allelic relationship between nod genes in R. meliloti and R. trifolii.     

Stimulation of 16-dehydroprogesterone and progesterone reductases of Eubacterium sp. strain 144 by hemin and hydrogen or pyruvate.

Suspensions of Eubacterium sp. strain 144, prepared from cells grown with 16-dehydroprogesterone, catalyzed the reduction of this steroid to 17-isoprogesterone at a very low rate. Modifications of the assay to optimize the pH (5.5) and increase the steroid solubility (10% [vol/vol] methanol) did not significantly enhance the reaction. However, growth of strain 144 in the presence of hemin was found to stimulate 16-dehydroprogesterone reductase during the initial 30 min of incubation, giving a biphasic time course. These biphasic kinetics could be eliminated by providing the cells with an exogenous electron donor. Strain 144 used either H2 or pyruvate for this purpose, and 17-isoprogesterone formation was nearly complete after 20 to 30 min of incubation. However, under these conditions, strain 144 further converted 17-isoprogesterone to products which lacked UV absorbance (254 nm). When progesterone was used as a substrate, it was found that strain 144 could reduce the C4-C5 double bond of this steroid by a progesterone reductase to give mostly 5 beta-pregnadione and some 5 alpha-pregnadione. Furthermore, the 3-keto group of 5 beta-pregnadione steroid was also reduced to a hydroxy function. The maximum activities of both 16-dehydroprogesterone and progesterone reductases in cell suspensions required the growth of strain 144 with hemin and 16-dehydroprogesterone and the presence of H2 or pyruvate.     

Control of sugar transport in human fibroblasts independent of glucose metabolism or carrier-substrate interaction

Transport regulation by different metabolizable and nonmetabolizable sugars was studied in human fibroblasts. Sugars were classed as glucose-like (D-mannose, 3-0-methyl-D-glucose, thio-D-glucose, and D-allose) and starvation-like (D-galactose, D-fructose, L-glucose, D-xylose, 6-deoxy-D-glucose and 2-deoxy-D-glucose) based on their competence in curbing glucose starvation enhanced transport. No significant correlation existed between the ability of a sugar to curb hexose transport and the KI of that sugar in inhibiting hexose transport. Independence of the transport curb from glucose metabolism was observed since nonmetabolizable analogs of D-glucose when substituted for D-glucose in the culture medium effected glucose [i.e. 3-0-methyl-D-glucose (3-OMG)] and starvation-like (i.e. 6- and 2-deoxy-D-glucose) effects. The KI of inhibition pf 2-deoxy-D-glucose transport for 3-OMG was 8.5 mM, similar to those obtained for 6-deoxyglucose and 2-deoxyglucose on 2-deoxyglycose transport (7.5 and 3.5 mM, respectively) and on 3-0-methylglucose transport (3.5 and 2.5 mM, respectively). An equimolar mixture of D-glucose and 3-OMG (5.55 mM each) was more effective than 11.1 mM D-glucose or 3-OMG alone in curbing hexose transport or reversing hexose starvation induced increases in transport. The effect of 3-OMG may be independent of glucose metabolism but it is possible that 3-OMG structurally mimics a metabolite of glucose that may interact with intracellular regulators of carrier degradation and or expression.     

Ginseng extract inhibits protein degradation and stimulates protein synthesis in human fibroblasts

Aqueous extracts of Panax ginseng inhibit intracellular protein degradation in confluent cultures of IMR-90 human diploid fibroblasts. The magnitude of the inhibition is similar to that observed with insulin and polypeptide growth factors. Furthermore, the inhibition of proteolysis by ginseng, like that produced by insulin and growth factors, is selective in that it applies to long-lived proteins but not to short-lived proteins. Ginseng also stimulates protein synthesis in human fibroblasts indicating that components of ginseng extract are capable of acting directly on human cells to promote protein accumulation.