Real-time stability measurement system for postural control

A method for assessing balance, which was sensitive to changes in the postural control system is presented. This paper describes the implementation of a force-sensing platform, with force sensing resistors as the sensing element. The platform is capable of measuring destabilized postural perturbations in dynamic and static postural conditions. Besides providing real-time qualitative assessment, the platform quantifies the postural control of the subjects. This is done by evaluating the weighted center of applied pressure distribution over time. The objective of this research was to establish the feasibility of using the force-sensing platform to test and gauge the postural control of individuals. Tests were conducted in Eye Open and Eye Close states on Flat Ground (static condition) and the balance trainer (dynamic condition). It was observed that the designed platform was able to gauge the sway experienced by the body when subject’s states and conditions changed.     

Study of apoptosis-related responses of leukemic blast cells to in vitro anthracycline treatment.

Anthracyclines trigger an apoptotic cell death but their molecular targets are not totally explored. We investigated the apoptotic response of blast cells and lymphocytes from medullary samples of 31 de novo acute leukemia. Mononuclear cells were treated in vitro by therapeutic concentrations of either daunorubicin (DNR) or idarubicin (IDA) for 1 h, washed and cultured for 18 h. A multivariate analysis using flow cytometry and a CD45 gating on lymphocytes and blast cells was performed. DNR and IDA induced a Fas enhancement on both leukemic and normal cells. In blast cells the DEVDases were activated and the caspase 3 was cleaved in relation to phosphatidyl serine exposure, showing a caspase-dependent pathway in anthracycline-induced apoptosis. Apoptotic percentages were always higher for blast cells than for lymphocytes, confirming that anthracycline toxicity mainly affected tumor cells. Moreover, drug-induced apoptosis was not related to spontaneous apoptosis, suggesting that variations in response intensities were due to individual variations of sensitivity rather than to programmed life span time. The apoptotic response of P-glycoprotein-expressing blast cells was not significant, giving biological argument for the poor prognosis of multidrug resistance leukemia. Finally, Fas induction and anthracycline-induced apoptosis on blast cells were significantly higher when a complete remission was achieved, thus shedding light on potential new prognostic factors in acute leukemia.     

Increased jejunal intraepithelial lymphocytes bearing gamma/delta T-cell receptor in dermatitis herpetiformis.

T-cell receptor 1 (gamma/delta) expression was studied in 19 jejunal or duodenal specimens from patients with dermatitis herpetiformis and in 16 jejunal or duodenal specimens showing normal histology. In normal specimens, gamma/delta+ cells represented 10.8% of intraepithelial CD3+ lymphocytes. Around 50% of these cells were recognized by the A13 monoclonal antibody, which detects products of the V gamma 1/V delta 1 gene rearrangement and the non-disulfide-linked form of T-cell receptor 1. The remaining 50% reacted with the BB3 monoclonal antibody, which recognizes products of the V gamma 9/V delta 2 rearrangement and the disulfide-linked form of receptor. Very few gamma/delta+ cells were observed in the lamina propria. In jejunal specimens from patients with dermatitis herpetiformis, a significant increase in the prevalence of gamma/delta+ intraepithelial lymphocytes was observed (P less than 0.001). This finding was largely accounted for by an increase in those cells recognized by the A13 monoclonal antibody, thus possibly expressing the V gamma 1/V delta 1 rearrangement and the nondisulfide-linked form of receptor. These data suggest that similar pathogenetic mechanisms may be active in determining the jejunal damage in celiac disease and dermatitis herpetiformis.     

A comparison of toxicity following two different doses of cyclophosphamide for mobilization of peripheral blood progenitor cells in 116 multiple myeloma patients

High-dose cyclophosphamide (HDC) has been shown to be an effective regimen for collecting PBPC in multiple myeloma (MM) patients, but the optimal dose to be used remains controversial. Two historical cohorts of MM patients who received G- or GM-CSF and HDC at the dose of either 7 g/m(2) (HDC7, n = 74) or 4 g/m (HDC4, n = 42) were compared. As patients in the HDC4 group were more likely to have received G-CSF than GM-CSF (P < 10(-3)) and fewer previous alkylating agents (P = 0.004), multivariate logistic regression analysis was performed. In the HDC4 group, patients had a shorter median duration of neutropenia (P < 10(-4)), fewer RBC (P < 10(-3)) and platelet transfusions (P < 10(-3)) with fewer patients with platelets <20 x 10(9)/l (P = 0.004). Moreover, fewer febrile episodes (P < 10(-3)) and less need of intravenous antibiotics (P < 10(-3)) were found in the HDC4 group. No statistical difference was observed with regard to CD34(+) cell collection efficiency. Thus, the use of HDC at the dose of 4 g/m(2) for the collection of PBPC in MM patients decreases hematological and extrahematological toxicity with an equivalent CD34(+) cell collection efficiency.     

Relation between left ventricular function and oxidative stress in patients undergoing bypass surgery

Objective—To determine whether preoperative left ventricular ejection fraction (LVEF) is related to the degree of myocardial oxidative stress during bypass surgery in man.
Design—Observational study.
Setting—Tertiary care centre.
Patients and interventions—31 patients (LVEF range was 20% to 68%) undergoing elective coronary bypass surgery with blood cardioplegic reperfusion were studied. Arterial and coronary sinus blood was collected before aortic cross clamping (T0) and at 0 (T1), 15 (T2), and 30 (T3) minutes after unclamping. Transmural left ventricular biopsies were also obtained from 15 patients at T0 and at T1.
Main outcome measures—Glutathione and adenine nucleotides were measured in myocardial biopsies, while coronary sinus-artery differences for glutathione, nucleotides, and products of lipid peroxidation were calculated from blood specimens. Creatine kinase (myocardial band; CK-MB) was measured in plasma at four and 12 hours after operation.
Results—Myocardial glutathione and adenine nucleotides were correlated (p < 0.02) with preoperative LVEF both at T0 (r = 0.909 and 0.672) and T1 (r = 0.603 and 0.605). Oxidised glutathione released from the heart during reperfusion was inversely correlated with LVEF (r = −0.448, −0.466, and −0461 at T1, T2, and T3, p < 0.01), while reduced glutathione (r = 0.519 and 0.640 at T1 and T2) and glutathione redox ratio (r = 0.647, 0.714, 0.645, and 0.702 at T0, T1, T2, and T3) showed a direct correlation (p < 0.01). Lipid peroxidation at T1 was negatively related to LVEF (r = −0.492). CK-MB was also negatively related to LVEF (r = −0.440 at 4 h and −0.462 at 12 h).
Conclusions—The capacity to counterbalance oxidative burst following ischaemia and reperfusion appears to be related to the functional ability of the heart.

Keywords: oxidative stress; glutathione; lipid peroxidation; aortocoronary bypass     

High-dose darbepoetin alpha in the treatment of anaemia of lower risk myelodysplastic syndrome results of a phase II study

An open-label, phase II non-randomised trial was conducted with darbepoetin (DAR), an erythropoiesis-stimulating factor with prolonged half-life, at a weekly dose of 300 mug subcutaneously in 62 anaemic patients with myelodysplastic syndrome (MDS) with an endogenous erythropoietin (EPO) level <500 mU/ml. Most of the patients were classified as low or intermediate 1 according to the International Prognostic Scoring System. After 12 weeks, 44 (71%) patients had an erythroid response (34 major and 10 minor), including eight of 13 patients who were previous non-responders to conventional EPO. Two additional responses (one minor and one major) occurred, in 10 non-responders, after the addition of granulocyte colony-stimulating factor (G-CSF). Thirty-six of the 46 total responders (31/35 major and 5/11 minor) continued to respond on maintenance DAR after a median of 40 weeks (range 4-84). Median dose of DAR required to maintain response was 300 microg every 14 d. The only prognostic factors of favourable response were low endogenous EPO level and low or absent red blood cell transfusion requirement. Those results suggest that high-dose DAR alone yields high erythroid response rates in anaemia of lower risk MDS, possibly equivalent to those obtained with conventional EPO + G-CSF, although this will need to be confirmed in larger and randomised trials.     

Karyotypic abnormalities in myelofibrosis following polycythemia vera

Polycythemia vera (PV) is a chronic myeloproliferative disease characterized by an increase of total red cell volume; in 10% to 15% of cases, bone marrow fibrosis complicates the course of the disease after several years, resulting in a hematologic picture mimicking myelofibrosis with myelocytic metaplasia (MMM). This condition is known as post polycythemic myelofibrosis (PPMF). Among 30 patients with PPMF followed in Northern France, 27 (90%) expressed one or two abnormal clones in myelocytic cell cultures. Of these, 19 (70%) had partial or complete trisomy 1q. This common anomaly either resulted from unbalanced translocations with acrocentric chromosomes, that is, 13, 14, and 15, or other chromosomes, that is, 1, 6, 7, 9, 16, 19, and Y, or from partial or total duplication of long arm of chromosome 1. A single patient had an isochromosome 1q leading to tetrasomy 1q. In all cases, a common trisomic region spanning 1q21 to 1q32 has been identified. Given that most patients had previously received chemotherapy or radio-phosphorus to control the polycythemic phase of their disease, this study illustrates the increased frequency of cytogenetic abnormalities after such treatments: 90% versus 50% in de novo MMM. Moreover, karyotype can be used to distinguish PPMF—where trisomy 1q is the main anomaly—from primary MMM where trisomy 1q is rare and deletions 13q or 20q are far more common. Whether trisomy 1q is or is not a secondary event remains a matter of debate, as well as the role of cytotoxic treatments.