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Biomedical subjects

A Baldi

Publications and source records attributed to A Baldi.

At least 163 records · Page 9Linked to original sources
PubMed1979

Transcriptional features of fractionated human breast tumor chromatin.

By means of controlled mechanical shearing it was possible to fractionate human breast tumor chromatin in "active" and "inactive" species, according to their in vitro template activity, using Escherichia coli RNA polymerase. The "active" molecules can be resolved in three well defined regions in an exponential sucrose gradient, showing approximately 300 times the efficiency for synthesizing ribonucleic acid, relative to the chromatin which migrated fastest. This technique could provide the initial tool to isolate eu-and heterochromatin from native human chromatin.

Breast Neoplasms↗
PubMed1977

Binding of estradiol receptor complexes to isolated human breast chromatin.

The interaction of estradiol-receptor complexes and isolated human breast tumor chromatin was studied under equilibrium conditions. The estradiol-receptor complexes bound specifically to the chromatin of hormone dependent tumors and showed a single class of binding sites with a Ka of 0.96 X 10(10) M-1 and a binding capacity of 1.5 pmoles/mg DNA. The binding was a temperature-dependent process and involved a "transformation" of the receptor protein. The heat-activated hormone-receptor complex was more active than the 8S form in the binding phenomenon. The specific interaction of estradiol-receptor complex with isolated chromatin was saturable and sensitive to conditions of temperature and ionic strength. Furthermore under optimal conditions no acceptor sites were detected in chromatin of hormone independent tumors.

Breast Neoplasms↗
PubMed1977

An improved procedure for purifying RNA tumor viruses from malignant tissue.

A convenient method for purifying RNA tumor viruses is described. Viruses banded in isopycnic gradients are contaminated with membranes that can be removed by velocity sedimentation in glycerol gradients. On sodium dodecyl sulfate (SDS) gel electrophoresis, the particles purified by these procedures from mouse mammary tumor tissue show protein profiles typical of those observed with virus purified from milk.

Animals↗
PubMed1976

Giant pilomatrixoma (Malherbe calcifying epithelioma).

The pilomatrixoma (Malherbe calcifying epithelioma) starts as a skin lesion, bearing a superficial resemblance to the common inclusion or sebaceous cysts. One of the largest cysts recorded appeared in a 56-year-old woman as an ulcerated, locally invasive tumor. The cyst demonstrated the typical ghost (shadow) cells, basophilic cells, keratin pearls, and calcifications. The lesion responded to wide excision and skin grafting. The result 17 months later was most satisfactory.

Face↗
PubMed1976

Steroid metabolism in rat submaxillary glands.

The ability of rat submaxillary gland to metabolize C21 steroids was studied by culturing explants with labeled progesterone, pregnenolone and 17 alpha-hydroxyprogesterone. The metabolites isolated were identified by paper chromatography, thin layer chromatography and combined gas liquid chromatography mass spectrometry. The radiochemical purity of certain metabolites was confirmed by recrystallization to constant specific activity. The capability of this gland to reduce C21 steroids was confirmed with the isolation of 3 alpha-hydroxy-5 alpha-pregnan-20-one and 5 alpha-pregnane-3 alpha, 20 beta-diol. The presence of delta 5, 3 beta hydroxy steroid dehydrogenase was shown by the conversion of pregnenolone to progesterone. Only in the incubations with 17 alpha-hydroxyprogesterone a compound with a molecular weight 290 was detected.

Animals↗
PubMed1975

[Behavior of lipoprotein X (LP-X) in viral hepatitis].

The AA. have studied the behaviour of LP-X in fifty cases of viral hepatitis printing out a positivity in 32% of the examined cases, with a positivity of the Au-antigen in the 34% of cases. They have observed a more remarkable inclination to the cholostasis in children (40% of the cases of positivity of LP-X), concluding for a scarce specificity of such a "marker" of cholostasis.

Apoproteins↗