Expression profile of MDM-2 proteins in chronic lymphocytic leukemia and their clinical relevance.

The MDM-2 oncoprotein exists in an autoregulatory feedback loop with the tumor suppressor protein p53. Therefore, intracellular levels of these two proteins may play important roles in cell proliferation and tumorigenesis. Several MDM-2 proteins (Mr 35-100 Kd) have been demonstrated in human cell lines.

Differential expression of lacZ in the liver and kidney of transgenic mice carrying chimeric lacZ-erythropoietin gene constructs with or without its 1.2 kb 3'-flanking sequence.

Erythropoietin (EPO) plays a key role in erythropoiesis and is expressed predominantly in the fetal liver and in the adult kidney. The EPO gene is up-regulated at the transcriptional level under hypoxic/anemic conditions. We studied the role of the 5'- and 3'-flanking sequences of the mouse EPO gene in its tissue-specific and hypoxia-induced expression by developing transgenic mouse lines carrying chimeric EPO-lacZ gene constructs.

Polycystic ovary syndrome: clinical and laboratory evaluation.

Objective: To evaluate clinically, and with laboratory, tests, women with polycystic ovary syndrome (PCO).

Patients: One hundred and twelve women with PCO were studied.

Methods: The following data was recorded: Current age; age at menarche; menstrual irregularity, occurrence of similar cases in the family; fertility, obstetric history; body mass index (BMI); and presence of hirsutism.

Comparative bioavailability study of an once-a-week matrix versus a twice-a-week reservoir transdermal estradiol delivery systems in postmenopausal women.

An open-label, randomised, crossover study was conducted with in healthy postmenopausal women to compare the relative bioavailability of a matrix transdermal estradiol delivery system worn for 7 consecutive days, versus a reservoir transdermal patch worn for 4 days followed by its immediate replacement by another patch worn for further 3 consecutive days. There was a minimum 7-day washout period between the two study periods. Both systems were labelled to release approximately 50 micrograms/day of estradiol.

Abnormal expression of MDM-2 in breast carcinomas.

MDM-2 is a cellular oncoprotein that binds to the p53 protein and abrogates its growth-suppressing function. At least seven MDM-2 mRNAs and five proteins (p90, p85, p76, p74, and p57) have been reported in tissue culture. MDM-2 gene amplification occurs in human sarcomas and high-grade gliomas.

p16INK4A and p15INK4B gene deletions in primary leukemias.

The 9p21 locus has been deleted at a high frequency in a wide variety of tumors. Recently, two genes, p16INK4A and p15INK4B (also called MTS1 and MTS2), have been localized in close proximity at the 9p21 locus, encoding cyclin-dependent kinases 4/6 inhibitors of relative molecular mass 16 kD and 15 kD, respectively and also found to be deleted at a high frequency in tumor cell lines. We analyzed p16INK4A and p15INK4B genes in 178 cases of primary leukemias including 81 cases of chronic lymphocytic leukemia (CLL), seven of hairy cell leukemia (HCL), seven of chronic myelogenous leukemia (CML), 43 of acute myelogenous leukemia (AML), 27 of acute lymphoblastic leukemia (ALL), and 13 of myelodysplastic syndrome (MDS) by Southern blot analyses.

Multiple patterns of MDM-2 deregulation in human leukemias: implications in leukemogenesis and prognosis.

The human analogue of the mouse double minute-2 (MDM-2) protein binds to p53 protein and abrogates its tumor-suppressing activity. MDM-2 overexpression may represent an alternative mechanism to p53 mutation for escaping the p53-mediated growth control. Interestingly, multiple MDM-2 protein isoforms have been described and the possibility of functional differences between various isoforms has been raised.

The role of calcium and N-linked glycans in the oligomerization and carbohydrate binding properties of human immunodeficiency virus external envelope glycoprotein.

Envelope glycoproteins of human immunodeficiency virus (gp120 and gp41) occur as oligomers. Here, we show by gel filtration analysis that gp120 oligomerization in vitro is calcium- and temperature-dependent. Recombinant gp120 (rgp120) species were recovered as monomers at 20 degrees C in the absence of calcium, but as tetramers at 37 degrees C in 10 mM CaCl2.

Premature ovarian failure: morphological and ultrastructural aspects.

The authors documented by means of light and transmission electron microscopy that the ovaries of women with premature ovarian failure (POF) displayed dense connective tissue and rare corpora albicantia. Eight of the ten studied cases did not present ovarian follicles; in two cases, it was verified the presence of ovarian follicles, atypical primordial follicles and in one case, a corpus luteum was identified (after stimulation with exogenous gonadotrophin). Regarding the ultrastructural analysis, it was noted that the fibroblasts were united one to each other by cellular prolongations that formed a woof, constituting a cellular syncicius.

Carbohydrate binding properties of the envelope glycoproteins of human immunodeficiency virus type 1.

Here, we confirm and extend our previous findings on human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein N-acetylglucosaminyl binding properties. We show the occurrence of saturable, temperature, pH, and calcium dependent carbohydrate-specific interactions between recombinant precursor gp160 (rgp160) and two affinity matrices: D-mannose-divinylsulfone-agarose, and natural glycoprotein, fetuin, also coupled to agarose. Binding of rgp160 to the matrices was inhibited by soluble mannosyl derivatives, alpha-D-Man17-BSA and mannan, by beta-D-GlcNAc47-BSA and by glycopeptides from Pronase-treated porcine thyroglobulin, which produces oligomannose and complex N-linked glycans.

Mannosyl/N-acetyl-beta-D-glucosaminyl binding properties of the envelope glycoprotein of human immunodeficiency virus type 2.

We have recently demonstrated that human immunodeficiency virus type 1 (HIV-1) recombinant envelope glycoprotein precursor gp160 (rgp160) behaves as a mannosyl/N-acetylglucosaminyl (GlcNAc) binding protein. If such a carbohydrate-binding property were of biological relevance it should be shared by other related primate immunodeficiency viruses such as HIV-2. The present study confirms this hypothesis and extends these findings by showing that HIV-2 recombinant gp140 (rgp140) specifically interacts with three affinity matrices substituted by synthetic or natural carbohydrate structures: D-mannose-divinylsulphone-agarose, para-aminophenyl-beta-D-GlcNAc-agarose and the natural glycoprotein, bovine fetuin, also coupled to agarose.

Sp1 is essential and its position is important for p120 gene transcription: a 35 bp juxtaposed positive regulatory element enhances transcription 2.5 fold.

Human proliferating cell nucleolar antigen p120 is expressed in tumor cells in the early G1 phase of the cell cycle. Deletion analyses of the essential cis-acting region -537/-278 showed that a 58 bp sequence from -457 to -400 is an important cis-acting element. An Sp1 transcription factor binds to the sequence AGAGGCGGGG (-425 to -416) within the -458/-400 cis-acting region.

Molecular biology of human renin and its gene.

This article describes investigations of several aspects of the molecular biology of the human renin gene and the three-dimensional structure of renin and its precursor, prorenin. Because of the importance of the RAS in hypertension, heart failure, renal failure, and possibly other disorders such as atherosclerosis, it is critical to understand the detailed control of this system. This control involves regulation at the transcriptional level, folding of prorenin, sorting of prorenin to a regulated pathway where it is proteolytically cleaved to renin and released in response to secretogogues, constitutive release of uncleaved prorenin, and nonproteolytic activation of prorenin.

Regulation of human renin expression in chorion cell primary cultures.

The human renin gene is expressed in the kidney, placenta, and several other sites. The release of renin or its precursor, prorenin, can be affected by several regulatory agents. In this study, primary cultures of human placental cells were used to examine the regulation of prorenin release and renin mRNA levels and of the transfected human renin promotor linked to chloramphenicol acetyltransferase reporter sequences.

The upstream sequence -537 to -278 is necessary for transcription of the human nucleolar antigen p120 gene.

Two cis-acting elements in the p120 gene play important roles in transcription; the region from -537 to -278 is necessary for initiation of transcription, and the region from -1426 to -1223 is necessary for efficient transcription. The distal element(s) which lies upstream of -278 is required for initiation of transcription.

Genomic structure of the human proliferating cell nucleolar protein P120.

A gene for human proliferating cell nucleolar protein p120 has been isolated from a human genomic library using p120 cDNA as a probe. The gene spanned 12 kilobase pairs and was composed of 15 exons and 14 introns. Unusual splice junction sequences, (AT) and (AC), instead of (GT) and (AG), respectively, were located at the splice sites for intron F.

The molecular biology of human renin and its gene.

The molecular biology of renin, prorenin, and the renin gene have been studied. A tissue-specific pattern of expression was found in rat and human tissues. In the human placenta, the transfected and endogenous renin promoters are active, and renin mRNA levels and transfected promoter activity are increased by a calcium ionophore plus cAMP.

Cloning of the cDNA and sequence of the human proliferating-cell nucleolar protein P120.

The 120 kDa proliferating-cell nucleolar antigen described by Freeman et al. (Cancer Res. 48:1244; 1988) is the most cancer specific of the proliferation-associated nucleolar proteins identified thus far.

Prominent IgM rheumatoid factor production by human cord blood lymphocytes stimulated in vitro with Staphylococcus aureus Cowan I.

We previously reported that Staphylococcus aureus Cowan I (SAC) is a potent stimulant of IgM rheumatoid factor (RF) production by normal adult peripheral blood mononuclear cells. In the current study, we compared the capacity of normal adult peripheral blood mononuclear cells and cord blood mononuclear cells to produce IgM RF. Although both populations of cells consistently produced IgM RF in response to SAC, the quantity of RF produced by cord blood cells (128 +/- 18 ng/ml, mean +/- SEM) greatly exceeded that of adult cells (37 +/- 5 ng/ml, p less than 0.

Human renin is correctly processed and targeted to the regulated secretory pathway in mouse pituitary AtT-20 cells.

Renin is formed by intracellular processing of prorenin and catalyzes the conversion of angiotensinogen to angiotensin I, the precursor to angiotensin II. Several tissues synthesize prorenin. However, in man, the kidney is the only known source of circulating renin, raising the possibility that the processing enzyme is unique to that tissue.

Staphylococcus aureus Cowan I. Potent stimulus of immunoglobulin M rheumatoid factor production.

These studies demonstrate that Staphylococcus aureus Cowan I (SAC), a protein A-positive Staphylococcal strain, is a potent and consistent inducer of IgM rheumatoid factor production by normal human peripheral blood mononuclear cells. The frequency and magnitude of this response greatly exceeded that of parallel cultures stimulated with pokeweed mitogen or the protein A-negative S. aureus Wood strain, although all three agents induced a similar amount of total IgM.

Bacterial peptidoglycan induces in vitro rheumatoid factor production by lymphocytes of healthy subjects.

The present studies were carried out to further characterize the polyclonal B cell activating properties of bacterial peptidoglycan (PG) and to determine if this ubiquitous agent induces in vitro IgM rheumatoid factor (RF) production by lymphocytes from healthy volunteers. Peripheral blood mononuclear cells (PBMC) were cultured in the presence of peptidoglycan, pokeweed mitogen (PWM), a standard polyclonal B cell activator, or additional culture medium. Supernatants were harvested on days 7-8 for determination of total IgM, total IgG, and IgM RF by an enzyme-linked immunosorbent assay (ELISA).