Distribution of acid alpha-naphthyl acetate esterase among human T lymphocyte subsets

Human T lymphocyte subsets, identified by means of OKT3, 4 and 8 monoclonal antibodies, were isolated by a fluorescence activated cell sorter (FACS IV) and analyzed for distribution of alpha-naphthyl acetate esterase (ANAE) activity. As compared to OKT8⁺ lymphocytes a higher proportion of OKT4⁺ lymphocytes was ANAE-positive exibiting a spot or dot-like pattern in the cytoplasm. OKT8 and 4 positive subsets showed a similar ANAE distribution in diffuse granular form. Although OKT4 and OKT8 populations presented a different ANAE dot-like reactivity, this marker did not allow as clear a distinction between them as that reported for T_G and T_M lymphocytes.     

Downmodulation of ERK activity inhibits the proliferation and induces the apoptosis of primary acute myelogenous leukemia blasts.

MAP kinase/ERK kinase (MEK)-extracellular signal-regulated kinase (ERK) kinases are frequently activated in acute myelogenous leukemia (AML), and can have prosurvival function. The purpose of this study was to induce downmodulation of MEK-ERK activation in AML primary blasts in order to detect the effect on cell cycle progression and on the apoptosis of leukemic cells. We investigated 14 cases of AML with high ERK 1/2 activity and four cases with undetectable or very low activity. After 24 h incubation of the AML blasts with high ERK activity using PD98059 (New England BioLabs, Beverly, MA, USA), a selective inhibitor of MEK1 phosphorylation, at concentrations of 20 and 40 microM, we observed a strong decrease in the levels of ERK1/2 activity. A significant decrease of blast cell proliferation compared with untreated controls was found. In contrast, the proliferation of blast cells that expressed low or undetectable levels of ERK activity was not inhibited. Time-course analysis demonstrated that the downmodulation of MEK1/2, ERK1 and ERK2 dual-phosphorylation was evident even after 3 h of treatment with 20 and 40 microM. The cleavage of poly(ADP-ribose) polymerase (PARP), an early sign of apoptosis, appeared after 18 h of PD98059 treatment at concentrations of 20 and 40 microM in eight of the 14 cases. After 24 h of treatment, cleaved PARP appeared in all 14 cases. Time-course analysis of cell cycle progression and apoptosis showed that PD98059 induced a G1-phase accumulation with low or undetectable levels of apoptosis after 24 h incubation; after 48 and 72 h incubation, a significant increase of apoptosis was observed. Thus, the primary effect of ERK downmodulation was a cell cycle arrest followed by the apoptosis of a significant percentage of the leukemic blasts.The preclinical model of leukemia treatment reported in this paper makes further comment with regard to MEK1 inhibition as a useful antileukemic target, and encourages the conducting of in vivo studies and clinical investigations.     

Thallium-201 myocardial perfusion imaging in patients with systemic lupus erythematosus

The cardiovascular system is frequently affected in systemic lupus erythematosus (SLE). The observation of clinical manifestations related to the presence of coronary artery disease has not been frequently documented in young SLE patients. In these patients, the presence of inflammatory or thrombotic vascular lesions is often documented by anatomo-histological studies in the absence of previous clinical manifestations. The purpose of this study was to evaluate the presence of myocardial perfusion defects in SLE patients. The study was carried out in 15 patients without clinical signs of myocardial ischemia, 1 male and 14 females, 24 to 64 years old, with a mean SLE duration of 10.2 +/- 7.5 years. All the patients had normal blood pressure; electrocardiogram and Doppler-echocardiographic analysis showed values in the normal range. All the patients underwent thallium-201 exercise stress imaging repeated 3 hours later at rest, with tomographic SPECT analysis. Exercise test was carried out until submaximal load, without induction of ST segment alterations or symptoms. Scintigraphic scan showed normal thallium-201 SPECT imaging in 11/15 patients, while the other 4 patients had a slight perfusion defect, 3 of them in the inferior segment, in 2 non reversible and in 1 reversible; 1 patient had a non reversible defect in the septal segment. These slight perfusion defects, prevalently non reversible, may sometimes be a false positive imaging. Our results are in contrast with the literature observations concerning the frequent incidence of thallium-201 perfusion defects in SLE patients. In young asymptomatic SLE patients, our study does not report very important data indicating myocardial ischemia and suggesting the presence of significant coronary obstruction or vasculitis.     

Schnitzler's syndrome: monoclonal gammopathy associated with chronic urticaria

Schnitzler's syndrome (SS) is defined by monoclonal gammopathy and chronic urticaria combined with at least two of the following features: fever, arthralgia or arthritis, bone pain, hepato- and/or splenomegaly, palpable lymph nodes, elevated ESR, and leukocytosis. We report a 49-year-old man with monoclonal IgM gammopathy and a 4-year history of recurrent urticarial rash, unexplained fever and arthralgias. The skin biopsy from an acute lesion revealed perivascular lymphocytic infiltrates consisting of CD4+ and CD8+ T lymphocytes. To our knowledge, this is the first report of an immunophenotypic characterization of skin infiltrates in SS. A lower CD4+/CD8+ ratio of circulating T lymphocytes was also detected. SS usually has a benign course, but in 15% of patients a lymphoproliferative disorder develops.     

Conservative approach in Peutz-Jeghers syndrome: Single-balloon enteroscopy and small bowel polypectomy

AIM: To assess the usefulness of the balloon assisted enteroscopy in preventing surgical intervention in pa-tients with Peutz-Jeghers syndrome (PJS) having a small bowel large polyps. METHODS: Seven consecutive asymptomatic pts(age 15-38 years) with PJS have been collected; six under-went polypectomy using single balloon enteroscopy(Olympus SIF Q180) with antegrade approach using push and pull technique. SBE system consists of the SIF-Q180 enteroscope, an overtube balloon control unit(OBCU Olympus Balloon Control Unit) and a dispos-able silicone splinting tube with balloon(ST-SB1). All procedures were performed under general anesthesia. Previously all pts received wireless capsule endos-copy(WCE). Prophylactic polypectomy was reservedmainly in pts who had polyps 15 mm in diameter. The balloon is inflated and deflated by a balloon control unit with a safety pressure setting range from-6.0 kPa to +5.4 kPa. Informed consent has been obtained from pts or parents for each procedure.RESULTS: Six pts underwent polypectomy of small bowel polyps; in 5 pts a large polyp 15 mm(range 20-50 mm in diameter) was resected; in 1 patient with WCE negative, SBE was performed for previous surgi-cal resection of gastrointestinal stromal tumors. In 2 pts endoscopic clips were placed due to a polypectomy. No surgical complication have been reported. SBE with resection of small bowel large polyps in PJS pts was useful to avoid gastrointestinal bleeding and emergency laparotomy due to intestinal intussuscep-tions. No gastrointestinal tumors were found in sub-sequent enteroscopic surveillance in all seven pts. In order surveillance, all pts received WCE, upper en-doscopy, ileocolonoscopy every 2 years. No pts had extraintestinal malignant lesions. SBE was performed when WCE was positive for significant polyps( 15 mm).CONCLUSION: The effective of prophylactic polyp-ectomy of small bowel large polyps( 15 mm) could be the first line treatment for conservative approach in management of PJS patients.