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1.
In a new case of interstitial del(2q), measurements of ribulose 5-phosphate 3-epimerase activity suggested that the locus for this enzyme might be localized to the subregion 2q32q33.3. 相似文献
2.
Milzani Aldo; Carrera Paolo; Bergna Giovanni; Colombo Roberto 《Bioinformatics (Oxford, England)》1986,2(1):19-22
A program in BASIC is described which allows accurate quantificationof some numerical parameters that can be objectively correlatedto biological indexes in sigmoid biological events. Attentionwas focused on the polymerization process of actin (a muscleprotein with a mol. wt of 42 000 daltons) studied as the variationin the OD360 index with time. The experimental points, if plotted,can be well approximated by a rational function of the typeOD360 = f(t), which passes through the origin and can be representedgraphically by a sigmoid curve. The program was very helpfulin comparing the experimental curves and in analysing significantparameters, such as maximum velocity and asymptote, that characterizethese curves and whose interpretation would otherwise be purelysubjective.
Received on July 11, 1985; accepted on January 13, 1986 相似文献
3.
Andrea Lami Aldo Marchetto Piero Guilizzoni Anselma Giorgis Julieta Masaferro 《Hydrobiologia》1994,274(1-3):57-64
Stratigraphic analyses of organic carbon, organic nitrogen and algal and bacterial carotenoids in short cores of profundal
sediments of four alpine lakes (Tovel, Leit, Paione superiore and Tom) were used to reconstruct their trophic history. In
addition, depth distribution of carbonaceous particle concentrations provided information on lake contamination from atmospheric
deposition.
In three lakes (Tovel, Leit and Tom), sedimentary carotenoids unique to sulfur photosynthetic bacteria (okenone and isorenieratene)
provide evidence of changes in the oxygen, light and sulfide conditions in the water column. All the lakes are oligotrophic
or moderately productive, and the algal community is dominated by Chlorophyta, Pyrrhophyta and Cryptophyta. Cyanobacteria
are rather poorly represented.
The steep increase of carbonaceous particles in the uppermost sediment layers of all the lakes suggests that lake contamination
by atmospheric transport of pollutants began in the 1940s to 1950s. These data, coupled with those from a parallel study on
Chrysophycean scale-inferred pH, indicate recent acidification in those which are poorly buffered (Paione superiore and Leit). 相似文献
4.
Binding of BiP to an assembly-defective protein in plant cells 总被引:5,自引:1,他引:4
Emanuela Pedrazzini Giovanna Giovinazzo Roberto Bollini Aldo Ceriotti Alessandro Vitale 《The Plant journal : for cell and molecular biology》1994,5(1):103-110
The binding protein (BiP) has been implicated as a mediator of protein folding and assembly in the endoplasmic reticulum of mammalian cells and has often been found in stable association with structurally defective proteins. To acquire information on the activity of BiP in plant cells, we have expressed in tobacco protoplasts the wild type form and an assembly-defective form of bean phaseolin. Phaseolin (PHSL) is a soluble, trimeric, storage glycoprotein co-translationally inserted into the lumen of the endoplasmic reticulum and then transported along the secretory pathway to the protein storage vacuoles. We have previously shown that a PHSL mutant in which the last 59 amino acids have been deleted (Δ363PHSL) is unable to form trimers and is retained in a pre-Golgi compartment when synthesized in Xenopus oocytes. When transiently expressed in tobacco leaf protoplasts, wild-type PHSL is correctly glycosylated and assembles efficiently and rapidly into trimers. Δ363PHSL is also correctly glycosylated but does not trimerize. Tobacco BiP and Δ363PHSL are co-immunoselected using either anti-PHSL or anti-BiP antibodies. Under the same conditions, co-immunoselection of BiP with wild-type PHSL is not detectable. The BiP bound to Δ363PHSL can be released by treatment of the complex with ATP, indicating that the binding is related to the proposed function of BiP in protein folding and assembly in the endoplasmic reticulum. These data indicate that BiP stably binds structurally defective proteins in plant cells. 相似文献
5.
Dryas iulia appears to have undergone a mode of evolution different from that of other members of its subfamily (Heliconiinae). While other species constitute highly subdivided and inbred populations, those ofD. iulia are thought to be large and uniform. Analyzing six samples from Southern Brazil (state of Rio Grande do Sul) in relation to three enzyme systems (EST, LAP, and PGM) and their mtDNA RFLP patterns, we found that they are very similar at the molecular level. TheF statistics for enzyme polymorphism data revealed that inbreeding makes a great contribution to the population homozygosity, sinceF IS equals 0.1322 andF ST equals 0.0023. Since the chi-square test showed thatF ST is not significant, we conclude that all localities belong to the same population. The mtDNA differentiation was about 12 times greater than for nuclear genes;F ST was equivalent to 0.0265. We suggest that this difference is due to a higher dispersal of males, in relation to females. 相似文献
6.
Aldo Ferretti Vincent P. Flanagan Joseph T. Judd Padmanabhan P. Nair Philip R. Taylor 《The Journal of nutritional biochemistry》1993,4(12)
Dietary supplementation with a fish oil concentrate (FOC) reduced the endogenous synthesis of prostacyclin (PGI2), as measured by the excretion of its major urinary catabolite, 2,3-dinor-6-oxo-PGF1α (PGI2-M). Thirty-four healthy men (24–57 years old) were given controlled diets and supplements that provided 40% of the energy from fat and a minimum of 22 mg/d of α-tocopherol for two consecutive experimental periods of 10 weeks each. During the experimental periods, the men received capsules containing 15 g/d of a placebo oil (PO) (period 1) or 15 g/d of the FOC (period 2). In addition to the PO or FOC, capsules contained 1 mg of α-tocopherol per g of fat as an antioxidant. The average daily excretion of PGI2-M during the last week of FOC supplementation (period 2) was 22% less (P = 0.0001) than at the end of the first period. These results are at variance with those reported in comparable human studies conducted by other investigators during the middle and late 1980s. A 20% reduction (P = 0.003) in the 11-dehydrothromboxane B2 to 2,3-dinor-6-oxo-PGF1α excretion ratio at the end of period 2 in this study demonstrates that a shift of the n-6 to n-3 polyunsaturated fatty acid ratio from 12.5 to 2.3 brings about a substantial modulation of the eicosanoid system. 相似文献
7.
Alfonso Pompella Caterina Cambiaggi Silvia Dominici Aldo Paolicchi Roberto Tongiani Mario Comporti 《Histochemistry and cell biology》1996,105(3):173-178
Confocal laser scanning fluorescence microscopy coupled to image analysis was employed in order to develop and evaluate procedures for the appraisal at the single-cell level of: (1) protein-bound 4-hydroxynonenal, the specific product of membrane peroxidation (by means of immunocytochemistry with biotin-avidin revelation); (2) protein oxidation (by reaction of protein carbonyls with 2,4-dinitrophenyl-hydrazine followed by immunocytochemistry of dinitrophenyl moieties); and (3) cellular protein thiols (by direct alkylation of sulfhydryl groups with thiol-specific fluorescent reagents possessing different cell permeabilities). The procedures proved able to reveal the subcellular distribution of cytochemical parameters useful as indices of oxidative stress conditions, and may allow redox phenotyping of isolated cells, which would provide an efficient tool in selected experimental models. 相似文献
8.
Alfonso Pompella Aldo Paolicchi Silvia Dominici Mario Comporti Roberto Tongiani 《Histochemistry and cell biology》1996,106(3):275-282
A number of studies indicate that cell proliferation can be modulated by changes in the redox balance of (soluble and protein)
cellular thiols. Free radical processes, including lipid peroxidation (LPO), can affect such a balance, and a role for LPO
in multistage carcinogenesis has been envisaged. The present study was aimed to assess the relationships between the protein
thiol redox status and the LPO process in chemically induced preneoplastic tissue. The Solt-Farber's initiation-promotion
model of chemical carcinogenesis in the rat liver was used. In fresh cryostat sections, preneoplastic lesions were identified
by the reexpression of γ-glutamyltranspeptidase (GGT) activity. In serial sections, different classes of protein thiols were
stained; in additional sections, LPO was elicited by various prooxidant mixtures and determined thereafter by the hydroxynaphthoic
hydrazide-Fast Blue B procedure. The incubation of sections in the presence of chelated iron plus substrates for GGT activity
leads to the development of LPO in selected section areas closely corresponding to GGT-positive lesions, indicating the ability
of GGT activity to initiate LPO. Protein-reactive thiols, as well as total protein sulfur, were decreased by 20–25% in cells
belonging to GGT-positive preneoplastic nodules, suggesting the occurrence of oxidative conditions in vivo. The incubation
of additional adjacent sections with the prooxidant mixture H2O2 plus iron(II), in order to induce the complete oxidation of lipid present in the section, showed a decreased basal concentration
of oxidizable lipid substrate in GGT-rich areas. The decreased levels of both protein thiols and lipid-oxidizable substrate
in GGT-positive nodules suggest that the observed GGT-dependent path-way of LPO initiation can be chronically operative in
vivo during early stages of chemical carcinogenesis, in cells expressing GGT as part of their transformed phenotype. 相似文献
9.
Five novel representatives of the yeast genus Candida isolated from advanced stages of wood degradation from fallen trunks of Eucryphia cordifolia Cav., Laurelia sempervirens Weim., Laurelia philippiana Weim., Nothofagus dombeyii (Mirb.) Blume, and Nothofagus obliqua (Mirb.) Blume, in the evergreen rainy Valdivian forest of southern Chile, are described and illustrated. They clearly differ from all accepted Candida species to warrant their establishment as five new species of yeasts: Candida coipomensis sp. nov., Candida ralunensis sp. nov., Candida laureliae sp. nov., Candida osornensis sp. nov., and Candida llanquihuensis sp. nov. 相似文献
10.
Four unusual Apiotrichum, isolated from decayed wood of Eucryphia cordifolia Cav., Nothofagus obliqua (Mirb.) Blume, and Laurelia sempervirens Wein., one of which was also isolated from the intestinal tract of Scaptomyza multispinosa Malloch (Diptera), are described and illustrated. These species differ from all the accepted Apiotrichum species (1–3) to warrant their establishment as four new species: Apiotrichum eucryphiae, Apiotrichum osvaldii, Apiotrichum futronensis and Apiotrichum nothofagi. 相似文献