Hypermethylation of CpG islands in the promoter region of the p15INK4B gene in childhood acute leukaemia

It has been reported that the cyclin-dependent kinase inhibitor (CDKI) gene p15INK4B is frequently inactivated by genetic alterations and may be responsible for various malignant tumours. Another way of inactivation of this CDKI is by hypermethylation of 5'CpG islands in the promoter region of the p15INK4B gene and this inactivation seems to be a frequent event in various haematological malignancies. In the present study, we investigated the methylation status of the p151NK4B gene to clarify its role in the pathogenesis of childhood acute myeloid (AML) and acute lymphoblastic leukaemia (ALL). The study included 23 cases of B-cell origin ALL, 13 cases of T-cell origin ALL, 32 cases of AML, and 10 apparently healthy controls. Hypermethylation was studied by methylation-specific polymerase chain reaction. Hypermethylation of the p15INK4B gene was more frequent in cases with T-cell origin ALL (46.2%), but similar among children with B-cell origin ALL (13.0%) and AML (18.8%). Hypermethylation of p15INK4B may be involved in the pathogenesis of T-cell origin ALL, but not in that of AML or B-cell origin ALL.     

Predictive factors for response to rituximab in Waldenstrom's macroglobulinemia

Rituximab is an active agent for the treatment of Waldenstrom's macroglobulinemia. However, many patients do not respond to this agent and several others develop secondary resistance. In order to identify clinical and laboratory parameters that could predict a higher likelihood for response, we evaluated 54 patients who were treated with single-agent rituximab. Twenty-four patients (44%)exhibited > or = 50% reduction of serum monoclonal protein. Previously untreated and pretreated patients had the same probability for response. Low response rates were noted in patients with serum monoclonal protein level > or = 40 g/L (17%) and serum albumin level < 35 g/L (14%). Furthermore, a multivariate analysis indicated that high serum monoclonal protein and low albumin were the dominant variables associated with shorter time to progression. The presence of 2, 1, or none of these variables was associated with median times to progression of 4 months, 11 months, and approximately 48 months, respectively. We conclude that patients with low levels of monoclonal protein and normal albumin are the best candidates for treatment with rituximab.     

Inhalation of concentrated particulate matter produces pulmonary inflammation and systemic biological effects in compromised rats

Although significant progress has been made over the past few years, there is still debate on the causal fractions that are responsible for particulate matter (PM)-associated adverse health effects. A series of 1-d inhalation exposures to concentrated ambient particles (CAPs) were performed in compromised rats, focusing on pulmonary inflammation and changes in blood factors as biological outcomes. Studies were carried out in The Netherlands at an urban background location in Bilthoven, an industrialized location in the city of Utrecht, as well as at a location that is heavily dominated by freeway emissions. It was hypothesized that exposure to CAPs resulted in oxidative stress in the lung, producing a release of inflammatory mediators, which in turn can result in cardiovascular effects. Both spontaneously hypertensive rats and rats preexposed to ozone were studied. The effects were studied at 2d postexposure, focusing on pathology and cell proliferation, bronchoalveolar lavage fluid (BALF) analysis (including cytokines, biochemistry, cell differentials, cell viability and proliferation, and Clara-cell 16 protein), and blood analyses (fibrinogen, Clara-cell 16 protein, Von Willebrand factor, and cell differentials). Using CAPs exposures as a binary term, mild inflammation (increased numbers of neutrophils) and increased lung permeability (protein and albumin leakage in BALF) were evident. In addition, CAPs also produced increased fibrinogen concentrations in blood of spontaneously hypertensive rats. In conclusion, inhalation up to 3700 microg/m3 CAPs in the size range of 0.15-2.5 microm did induce statistically significant effects in the lung and blood, but the effects observed may not potentially be very biologically relevant. PM mass concentrations and lung permeability were weakly associated. This suggests that other PM metrics might be more appropriate.     

Prophylactic intravenous ondansetron and dolasetron in intrathecal morphine-induced pruritus: a randomized, double-blinded, placebo-controlled study

Pruritus is the most common side effect of intrathecal morphine for postoperative pain relief. Activation of central 5-hydroxytryptamine subtype 3 (5-HT3) receptors is one of its possible mechanisms. The role of 5-HT3 antagonists in the prevention of pruritus has not been clearly established. In a prospective, randomized, double-blind, placebo-controlled study, we evaluated the efficacy of prophylactic administration of ondansetron and dolasetron for the prevention of intrathecal morphine-induced pruritus. The patients were randomized into 3 groups to receive either 4 mg ondansetron IV (group O, n = 35), 12.5 mg dolasetron IV (group D, n = 35) or 5 mL placebo (group P, n = 35) 30 min before administration of spinal anesthesia with 10 to 17.5 mg of 0.5% hyperbaric bupivacaine and 0.25 mg of morphine for urologic, orthopedic, or vascular surgery. Patients were evaluated for incidence and severity of pruritus at arrival to the postanesthesia care unit and at 2, 4, 8, and 24 h postoperatively. The incidence and severity of pruritus was significantly less frequent in the ondansetron and dolasetron groups compared with placebo (34%, 20%, and 66% respectively, P < 0.01). Patients who received 5-HT3 antagonist reported significantly less total severity of pruritus compared with placebo during the first 8 h and the severe pruritus was observed only in patients within P group (P group: 4 of 35; 11%, O or D group: 0 of 35; 0%, P < 0.05). We conclude that the prophylactic use of ondansetron and dolasetron helps to reduce the incidence and severity of intrathecal morphine-induced pruritus.     

Early left ventricular function recovery after trap-door coronary transfer repair of ALCAPA in an adult patient

Anomalous origin of the left coronary from the pulmonary artery (ALCAPA) is a rare congenital malformation, which may result in myocardial infarction, congestive heart failure, and sudden death if left untreated. Despite frequently advanced pathologic changes, there seems to be significant potential for the recovery of myocardial function in individuals with left ventricular dysfunction after the establishment of physiologic coronary circulation, particularly in the pediatric population. Reports of ALCAPA repair in adulthood are scarce and little information exists regarding the response of the left ventricle to revascularization in this age group. In this report, repair of ALCAPA in a significantly symptomatic adult patient with ventricular dysfunction is described, leading to an early recovery of left ventricular function.     

Redox activity of airborne particulate matter at different sites in the Los Angeles Basin

Epidemiologic studies have shown associations between ambient particulate matter (PM) and adverse health outcomes including increased mortality, emergency room visits, and time lost from school and work. The mechanisms of PM-related health effects are still incompletely understood, but a hypothesis under investigation is that many of the adverse health effects may derive from oxidative stress, initiated by the formation of reactive oxygen species (ROS) within affected cells. While the adverse effects from PM have historically been associated with the airborne concentration of PM and more recently fine-particle PM, we considered it relevant to develop an assay to quantitatively measure the ability of PM to catalyze ROS generation as the initial step in the induction of oxidative stress. This ability of PM could then be related to different sources, chemical composition, and physical and spatial/temporal characteristics in the ambient environment. The measurement of ROS-forming ability in relation to sources and other factors will have potential relevance to control of redox-active PM. If oxidative stress represents a relevant mechanism of toxicity from PM, the measurement of redox activity represents a first step in the elucidation of the subsequent downstream processes. We have developed an assay for PM redox activity, utilizing the reduction of oxygen by dithiothreitol which serves as an electron source. We have found that PM will catalyze the reduction of oxygen and have examined the distribution and chemical characteristics of the redox activity of PM fractions collected in different sites in the Los Angeles Basin. Samples of concentrated coarse, fine, and ultrafine PM, obtained with aerosol concentrators, were studied with regard to their chemical properties and redox activity. Redox activity was highest in the ultrafine fraction, in agreement with results indicating ultrafines were the most potent toward inducing that heme oxygenase expression and depleting intracellular glutathione, which has relevance to induction of oxidative stress. Comparison of the redox activity with chemical composition showed a reasonable correlation of redox activity with elemental carbon (r(2)=0.79), organic carbon (r(2)=0.53), and with benzo[ghi]perylene (r(2)=0.82), consistent with species typically found in mobile emission sources.     

Ophthalmologic findings in cerebrofaciothoracic dysplasia

We describe the ophthalmologic findings in two cases of cerebrofaciothoracic dysplasia, a rare syndrome characterized by facial dysmorphism, multiple malformations of the vertebrae and ribs, and significant mental retardation. Both affected individuals are members of the same family and have epicanthal folds and hypertelorism. In addition, one patient has bilateral bull's eye maculopathy, which may represent an additional severe manifestation of cerebrofaciothoracic dysplasia syndrome.     

Unusual retrograde movement of a safety-pin ingested by an infant

Here we present the first reported case of an ingested open safety-pin in a 7-mo-old boy that migrated from the stomach to the oesophagus. CONCLUSION: This rare complication is probably due to a gastro-oesophageal reflux effect, and for this reason we propose that all infants with safety-pins and other sharp objects in the stomach should be positioned in a semi-upright position.     

Plasticity of dynamic muscle performance with strength training in elderly humans

Data are scarce relating to the plasticity with strength training of dynamic muscle performance in older humans. Hence, we investigated alterations in the torque-velocity relation with strength training in old age, and their origin. Knee extension and leg-press exercises were performed three times per week for 14 weeks. Maximal isokinetic knee extension torque was assessed during concentric and eccentric muscle actions. Agonist-antagonist muscle activation was assessed using electromyography. Vastus lateralis muscle architecture was examined in vivo using ultrasonography. Training increased concentric torque by 22-37% (P < 0.01), but failed to alter eccentric torque (P > 0.05). Increased agonist muscle activation, increased muscle fascicle lengths, and greater elastic energy recovered from tendinous structures may explain the adaptations during concentric actions, whereas the failure of eccentric torque to increase might be explained by the preservation of eccentric force with aging and an underloading of the eccentric movement phase during training. These findings may have important implications for dynamic muscle performance in old age.     

Effect of hormone therapy and raloxifene on serum VE-cadherin in postmenopausal women

OBJECTIVE: To investigate the effect of continuous combined hormone therapy and raloxifene on serum VE-cadherin. DESIGN: The study was double blinded, with a placebo run-in period of 28-50 days. SETTING: University menopause clinic. PATIENT(S): Twenty-eight healthy postmenopausal women devoid of climacteric complaints. INTERVENTION(S): Subjects were randomized to 17beta-estradiol (2 mg) + norethisterone acetate (1 mg; E(2)-NETA) or raloxifene hCL (60 mg) for a period of 6 months. MAIN OUTCOME MEASURE(S): Serum VE-cadherin, which was estimated at baseline and at month 6. RESULT(S): Serum VE-cadherin decreased significantly in both E(2)-NETA and raloxifene groups (raloxifene baseline +/- SD: 1.17 +/- 0.44 ng/mL, 6 months: 0.82 +/- 0.29 ng/mL; E(2)-NETA baseline: 1.19 +/- 0.47 ng/mL, 6 months: 0.92 +/- 0.49 ng/mL). Percentage changes from baseline were -21.7 +/- 24.3 for E(2)-NETA and -26.0 +/- 20.6 for raloxifene. CONCLUSION(S): The effect of E(2)-NETA and raloxifene suggests that these drugs may preserve interendothelial junction integrity and control vascular permeability. Although this effect may influence the progress of the atheromatous lesion, its clinical impact on coronary artery disease (CAD) remains uncertain.