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D Radu

Publications and source records attributed to D Radu.

At least 19 recordsLinked to original sources
PubMed2004

In situ localization of mRNA for the fibrinolytic factors uPA, PAI-1 and uPAR in endometriotic and endometrial tissue.

Endometriotic tissue grows invasively. The plasminogen-activating system is suggested to participate in degradation of extracellular matrix (ECM) and modulation of cell adhesion and migration. We have previously demonstrated elevated levels of the fibrinolytic factors urokinase plasminogen activator (uPA) and plasminogen activator inhibitor (PAI-1) in endometriotic tissue and endometrium from women with endometriosis. The aim of the present study was to localize the uPA, PAI-1 and urokinase plasminogen activator receptor (uPAR) mRNA in endometriotic tissue and in endometrium both from women with and without endometriosis. With in situ hybridization, we found that uPA mRNA seems to be up-regulated in endometriotic glands and endometrial stroma as well as PAI-1 mRNA in endometriotic and endometrial stroma from women with endometriosis. uPAR mRNA likewise appears to be up-regulated in both glands and stroma in endometriotic tissue and in endometrial glands from patients compared to endometrial glands and stroma from healthy women. These differences might be important for menstrual shedding and adherence of endometrial fragments to peritoneal lining in women developing endometriosis and for the invasive growth of endometriotic tissue.

Endometriosis↗
PubMed2001

Delayed stress-induced increase in tissue level of cholecystokinin in rat prefrontal cortex: modulation by microdialysis probe implantation and systemic ketamine.

In the brain, the neuropeptide cholecystokinin (CCK) appears to be involved in the mediation of stress responses. Here we provide new evidence that mild stress induces long-term changes in CCK-like immunoreactivity (CCK-LI) in the prefrontal cortex (PFC). The changes in CCK-LI show a biphasic pattern, with a decrease 20 min after and an increase 8 h after mild stress. These changes seem to be region specific. Measurement of CCK mRNA in prefrontal cortex neurons 4 or 8 h after the stress stimulus did not reveal changes in mRNA levels, suggesting that afferent CCK-containing neuron terminals may be more affected than local cortical CCK-ergic neurons. Furthermore, treatment with the glutamate NMDA receptor antagonist ketamine, led to more pronounced decreases in CCK-LI observed within 20 min after mild stress and counteracted the stress induced increase in cortical CCK-LI levels observed at 8 h. Implantation of a microdialysis probe in the PFC affected the response to mild stress, with no significant decrease in the CCK-LI level 20 min after, and attenuated reactivity to stress 8 h after the saline injection. Our results indicate that a mild stressful stimulus such as an intraperitoneal saline injection may have long-lasting effects on CCK-ergic transmission in the PFC. The use of microdialysis to study stress induced in vivo CCK-LI release in awake animals may, however, be significantly compromised by the impact of the microdialysis probe implantation on CCK-ergic mechanisms in the PFC. In addition, we hypothesize that subanesthetic doses of the psychotomimetic drug ketamine interfere with CCK-ergic mechanisms in the PFC during stress.

Animals↗
PubMed2000

Diagnosis of Fragile X syndrome by Southern blot hybridization using a chemiluminescent probe: a laboratory protocol.

BACKGROUND: Unequivocal molecular characterization of the FMR-1 triplet expansion region requires the combined use of PCR to amplify normal- and premutation-length alleles and Southern analysis to detect fully expanded alleles and assess methylation. We provide a detailed laboratory protocol, which can be generalized, for the preparation and use of a digoxigenin (DIG)-labeled probe for Southern analysis of genomic DNA digested with EcoR I and Eag I. METHODS AND RESULTS: The StB12.3 probe cloned in a recombinant plasmid is labeled by PCR amplification using M13 primers, in the presence of DIG-11-dUTP. Hybridization signal is visualized on x-ray film using an alkaline phosphatase anti-DIG-Fab conjugate in the presence of chemiluminescent substrate CDP-Star (Tropix, Bedford, MA). We provide details of probe labeling and quantitation, preparation, and hybridization of the alkaline Southern blot and an analysis of data. CONCLUSION: Several publications describe PCR-based methods that claim to preclude the requirement of Southern analysis for the diagnosis of Fragile X syndrome. However, none of these is as robust as the method described here. Currently, rapid Southern analysis is an important part of molecular detection of all possible normal and abnormal FMR-1 alleles. This nonradioactive approach is a convenient and rapid alternative to using a radioactive probe.

Blotting, Southern↗
PubMed1999

Failure of rearranged TCR transgenes to prevent age-associated thymic involution.

After puberty, the thymus undergoes a dramatic loss in volume, in weight and in the number of thymocytes, a phenomenon termed age-associated thymic involution. Recently, it was reported that age-associated thymic involution did not occur in mice expressing a rearranged transgenic (Tg) TCRalphabeta receptor. This finding implied that an age-associated defect in TCR rearrangement was the major, if not the only, cause for thymic involution. Here, we examined thymic involution in three other widely used MHC class I-restricted TCRalphabeta Tg mouse strains and compared it with that in non-Tg mice. In all three TCRalphabeta Tg strains, as in control mice, thymocyte numbers were reduced by approximately 90% between 2 and 24 mo of age. The presence or absence of the selecting MHC molecules did not alter this age-associated cell loss. Our results indicate that the expression of a rearranged TCR alone cannot, by itself, prevent thymic involution. Consequently, other presently unknown factors must also contribute to this phenomenon.

Aging↗
PubMed1999

Autoradiographic studies of 5-HT1A-receptor-stimulated [35S]GTPgammaS-binding responses in the human and monkey brain.

G-protein activation mediated by serotonin 5-HT1A receptors in human and monkey brain was investigated by using quantitative autoradiography of agonist-stimulated [35S]GTPgammaS binding to whole-hemisphere brain sections. [35S]GTPgammaS binding was stimulated by the mixed 5-HT1A/1B/1D agonist L 694247 (10 microm) in human brain regions enriched in 5-HT1A binding sites [e.g. hippocampus (132-137%), superficial layers of the neocortex (37-61%), and cingulate and entorhinal cortex (34 and 32%, respectively)]. L 694247 caused virtually no stimulation in regions with 5-HT1B/1D receptors, such as substantia nigra, caudate nucleus and putamen. Similar results were obtained with monkey brain sections. The L 694247-mediated [35S]GTPgammaS-binding responses in human and monkey brain sections were antagonized by the selective, silent 5-HT1A antagonist WAY 100635 (10 microm). The 5-HT1B inverse agonist SB 224289 (10 microm) did not affect the [35S]GTPgammaS-binding response of L 694247. The distribution pattern of the [35S]GTPgammaS-binding response and the antagonist profile suggest the L 694247-induced response in human and monkey brain is mediated by 5-HT1A receptors. A weak stimulation of [35S]GTPgammaS binding was also observed in human hippocampus with either 10 microm 8-OH-DPAT (25 +/- 4%) or naratriptan (42 +/- 2%) compared with that obtained with L 694247. In conclusion, G-protein activation by 5-HT1A receptors can be measured in human and monkey brain sections. L 694247 appears to possess higher efficacy at 5-HT1A receptors compared with 8-OH-DPAT and naratriptan.

8-Hydroxy-2-(di-n-propylamino)tetralin↗
PubMed1995

Immune response against the murine mdri protein induced by vaccination with synthetic lipopeptides in liposomes.

Intrinsically, or after exposure to chemotherapeutic drugs, many cancer cells overexpress a class of high molecular weight membrane glycoproteins associated with the multidrug resistance (mdr) of these cells. This report describes an immunization protocol eliciting autoantibodies specific to extracellular epitopes of the murine mdr 1 P-glycoprotein (Pgp). Synthetic peptides with the sequences of extracellular loops of murine Pgp were covalently coupled with four palmitic acid moieties per peptide molecule. These "lipopeptides" were reconstituted in the bilayer of liposomes containing lipid A and used to immunize mice. Antibodies against the lipopeptides corresponding to loop 2 and 4 were elicited in sera of immunized mice. They reacted specifically with extracellular epitopes of the naturally occurring murine Pgp. After interaction with resistant cancer cells, the antibodies induced an average 50% increase in cellular accumulation of doxorubicin and Bodipy-verapamil. In the presence of these antibodies the resistance of L1210 mdr cells was reduced from an LD50 of 4 x 10(-5) M to 5 x 10(-7) M doxorubicin.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1980

Facial plastic surgery in children with Down's syndrome.

Six minor corrections in the face of children with Down's syndrome can clearly improve their facial expression. Reduction of macroglossia facilitates phonation. Augmentation of the bridge of the nose effaces the epicanthus. The lid axis, the hypotonic lower lip, and microgenia can be repaired. While the parents have been satisfied with the results of surgery, a positive effect on social behavior and mental development of the children has not yet been proven.

Adolescent↗
PubMed1977

[Tissue levels following intravenous administration of tetracyclines (author's transl)].

Interested by a comparative trial on tetracycline concentrations in gallbladder, bile and peritoneum 3 hours after administration, we wanted to know the long-term tissue concentrations, measured towards the end of a 24-hour off-drug interval, as these concentrations are particularly important for a bacteriostatic drug. We found that the tissue concentrations of doxycycline in gallbladder wall, lung, muscle, and thyroid gland were 2 to 3 times higher than those of pyrrolidino-methyltetracycline. The concentrations in the skin, in various sections of the intestinal tract and of the peritoneum, and in the gallbladder content were about the same for both drugs. The implications of these data for therapy are discussed.

Bile↗
PubMed1976

Immune complexes in chronic hepatitis.

Rheumatoid factors were present in 33.2%, crioglobulins in 47.6%, and anticomplementary assay in 34.2% of cases with chronic active hepatitis. No statistically significant loss of total complement was observed, but its components especially C1 and C3, exhibited lowered titers in 48.6% and respectively 45.7% of 160 cases. The origin, significance and pathogenicity of these factors are discussed in connection with the presence and possible role of the immunologic complexes to the development of chronic liver injury.

Antigen-Antibody Complex↗