[Changes in esophageal peristalsis in diverse clinical forms and antibody specificity in scleroderma: a scintigraphic study in 100 cases]. / Alterazioni della peristalsi esofagea nelle diverse forme cliniche e specificita' anticorpali della sclerodermia: studio scintigrafico in 100 pazienti.

OBJECTIVE: To define the prevalence and severity of esophageal involvement in systemic sclerosis (SSc) and its relationship with the different clinical forms and ANA specificities of the disease. METHODS: A hundred consecutive patients with SSc, 48 with cutaneous limited, 26 with intermediate and 26 with diffuse form of disease, 49 with anti-centromere and 37 with anti-Scl70 ANA pattern, were submitted to scintigraphy using a semisolid orally ingested bolus to detect esophageal hypomotility. RESULTS: An impairment of esophageal function has been observed in 68% of SSc patients. Esophageal dysmotility was significantly more frequent and severe in patients with cutaneous diffuse and intermediate forms of SSc and with anti-Scl70 ANA pattern. CONCLUSIONS: Esophageal involvement is very common in SSc. The scintigraphy confirms to be a useful and non invasive diagnostic method; moreover it permits to quantify the severity of the esophageal dysmotility by analyzing both global and segmental function.

A comparative study of cellular and molecular pharmacology of doxorubicin and MEN 10755, a disaccharide analogue.

MEN 10755 is a disaccharide anthracycline endowed with a broader spectrum of antitumour activity than doxorubicin (DOX). To investigate the cellular and molecular basis of its action, cytotoxic activity, drug uptake, subcellular localisation, induction of DNA damage, and apoptosis were assessed in the human A2780 ovarian carcinoma cell line. Experiments with radiolabelled anthracyclines indicated that MEN 10755 exhibited reduced cellular accumulation and a different subcellular distribution (higher cytoplasmic/nuclear ratio) than DOX. In spite of the lower nuclear concentration, MEN 10755 was as potent as DOX in eliciting DNA single- and double-strand breaks, G2/M cell arrest, and apoptosis. Sequencing of drug-induced topoisomerase II cleavage sites showed a common DNA cleavage pattern for MEN 10755 and DOX. Cleavage sites were always characterised by the presence of adenine in -1 position. However, the extent of DNA cleavage stimulation induced by MEN 10755 was greater than that produced by DOX. Reversibility studies showed that MEN 10755-stimulated DNA cleavage sites were more persistent than those induced by DOX, thus suggesting a more stable interaction of the drug in the ternary complex. As a whole, the study indicated that the cellular pharmacokinetics of MEN 10755 substantially differs from that of DOX, showing a lower uptake and a different subcellular disposition. In spite of the apparently unfavourable cellular pharmacokinetics, MEN 10755 was still as potent as DOX in inducing topoisomerase-mediated DNA damage. Although the extent and persistence of protein-associated DNA breaks may contribute to the cytotoxic effects, the drug's efficacy as apoptosis inducer and antitumour agent could not be adequately explained on the basis of DNA damage mediated by the known target (i.e. topoisomerase II), thus supporting additional cellular effects that may be relevant in cellular response.

Apoptotic events in a human ovarian cancer cell line exposed to anthracyclines.

Cytotoxic drugs commonly used in cancer therapy promote tumor cell death by inducing apoptosis, but the cell death pathway(s) is likely dependent on the mechanism of drug action. In the present study, we investigated the mechanisms of cell death induced by doxorubicin (DXR) and the novel disaccharide anthracycline MEN 10755, in a human ovarian cancer cell line (A2780). Exposure to either anthracycline induced the up-regulation of several genes known to promote cell cycle arrest and DNA repair (WAF1/p21, GADD45) or apoptosis (bax, Fas). Although the expression of Fas was increased, an antagonistic anti-Fas antibody ZB4 did not inhibit anthracycline-induced apoptosis, suggesting that the stimulation of the Fas receptor did not play a critical role in the induction of apoptosis in this cell line. We also observed that neither MEN 10755 nor DXR were able to induce apoptosis in A2780 cells deprived of the nucleus but retaining an intact mitochondrial function (cytoplasts) and that apoptosis induced by either anthracycline was inhibited by cycloheximide, indicating that it is an active process requiring new protein synthesis. Both the caspases inhibitors, ZVAD-fmk and DEVD-cho, inhibited at similar extent apoptosis induced by either DXR or MEN 10755, suggesting an involvement of caspase-3 in this response. We conclude that, in a tumor cell line of epithelial origin, the apoptosis following exposure to anthracyclines is an active process requiring protein synthesis and drug interaction with nuclear structures. The pathway was Fas-independent but likely involved bax and caspase-3 as effectors of the cascade culminating in apoptosis.

Long-term therapy with plasma exchange in systemic sclerosis: effects on laboratory markers reflecting disease activity.

Plasma exchange (PEX) is a technique that has been applied to the treatment of many immunological disorders, including connective tissue diseases. The crucial role of some humoral factors in the pathogenesis of systemic sclerosis (SSc) could explain the good clinical results obtained in terms of slowing down the disease progression, but the efficacy of PEX in the treatment of SSc is not yet well defined, owing to the lack of controlled studies and validated parameters of disease activity. To demonstrate the long-term efficacy of PEX in the treatment of SSc we treated a group of 28 SSc patients affected with recent onset and/or rapidly progressive disease. Most of these had a diffuse form of SSc, with anti-Sc170 antibody as a disease marker. Before and after long-term PEX treatment we evaluated disease activity parameters including the serum levels of interleukin 2 soluble receptor (sIL-2R) and aminoterminal type III procollagen peptide (PIIINP), plus the percentage of DR+ T cells in the peripheral blood. We also assessed clinical parameters of total skin score and total visceral score. The same parameters were evaluated in 25 SSc patients who did not satisfy the admission criteria for PEX, treated long-term with drugs only. At baseline, serum PIIINP and sIL-2R levels and the percentage of DR+ T cells were significantly increased in PEX patients as compared to others. Following long-term PEX treatment, all the laboratory parameters significantly decreased and the clinical scores showed a slight but not significant improvement. Conversely, in the other group of SSc patients treated for the same period with drugs only, no significant change of laboratory parameters was detected and the clinical scores slightly worsened. Our data suggest that long-term PEX therapy seems to be effective in slowing down the clinical course of patients with severe and rapidly progressive SSc.

[Cytogenetic analysis in couples with spontaneous abortions]. / Badania cytogenetyczne u malzenstw z poronieniami samoistnymi.

Cytogenetic studies were performed in 129 couples with the history of recurrent spontaneous miscarriages. In 8 couples (6.2%) chromosome aberrations were found The most frequent aberrations were reciprocal translocations (in 6 couples). Pericentric inversion of chromosome 9 was detected in 3 couples (2.3%) while the chromosome polymorphism was observed in 20% of analyzed cases.

Expression and characterization of a mouse/human chimeric antibody specific for EGF receptor.

Murine antibodies which recognize the epidermal growth factor receptor (EGF-r) are good candidates for therapy and diagnosis of tumors overexpressing this receptor. Here we report the isolation of the variable regions from a murine monoclonal antibody anti-EGF-r (Mint5), the procedure to obtain the mouse/human chimeric antibody (chMint5) and its expression in COS, NS0 and CHO cells. The approach followed to construct chMint5 is based on the use of consensus primers specific for the ends of the variable regions. The sequence imposed by the primers did not affect the targeting potential of the antibody. In fact, the affinity of the chimeric antibody for EGF-r was nearly the same as that of the parental murine antibody. Based on previous in vitro and in vivo animal studies. Mint5 was shown to be a good candidate for the targeting of EGF-r overexpressing tumours. chMint5 is expected to be less immunogenic than murine antibody and therefore, could be useful for human treatment.

Interleukin-2 bolus therapy induces immediate and selective disappearance from peripheral blood of all lymphocyte subpopulations displaying natural killer activity: role of cell adhesion to endothelium.

As early as 10-15 min after the start of a 30 min interleukin-2 (IL-2) infusion, a rapid, virtually complete disappearance of all natural killer (NK) lymphocyte subpopulations (including both CD3- CD56+ and CD3+ CD56+ cells with either alpha/beta or gamma/delta T-cell receptor) was observed from peripheral blood. In contrast, the number of T lymphocytes (CD3+ CD56-) was unmodified for at least 2 h after IL-2 injection. The IL-2-induced, rapid disappearance from peripheral blood of NK and NK-like lymphocytes may be related to their massive adherence to the activated endothelium. In this regard, IL-2 infusion caused a very rapid rise of tumour necrosis factor-alpha (TNF-alpha) plasma concentration, whereas other cytokines, such as interferon-gamma (IFN-gamma), were induced only at later times. In vitro experiments indicated that IL-2, either alone or better combined with TNF-alpha, exerts a rapid and selective stimulatory effect on NK adhesion to endothelial cells. On the basis of these findings, we suggest that the activation of NK lymphocytes induced by IL-2, alone or combined with TNF-alpha, plays a key role in mediating the massive and selective adherence of NK and NK-like cells following IL-2 bolus infusion.