Capacitive performance of vertically aligned reduced titania nanotubes coated with Mn2O3 by reverse pulse electrodeposition

In this study, a composite material, manganese oxide/reduced titania nanotubes (Mn₂O₃/R-TNTs), was synthesized through incorporation of Mn₂O₃ onto R-TNTs via the reverse pulse electrodeposition technique. The influence of pulse reverse duty cycles on the morphological, structural and electrochemical performance of the surface was studied by varying the applied duty cycle from 10% to 90% for 5 min total on-time at an alternate potential of −0.90 V (E_on) and 0.00 V (E_off). FESEM analysis revealed the uniform deposition of Mn₂O₃ on the circumference of the nanotubes. The amount of Mn₂O₃ loaded onto the R-TNTs increased as a higher duty cycle was applied. Cyclic voltammetry and galvanostatic charge–discharge tests were employed to elucidate the electrochemical properties of all the synthesized samples in 1 M KCl. The specific capacitance per unit area was greatly enhanced upon the incorporation of Mn₂O₃ onto R-TNTs, but showed a decrease as a high duty cycle was applied. This proved that low amounts of Mn₂O₃ loading enhanced the facilitation of the active ions for charge storage purposes. The optimized sample, Mn₂O₃/R-TNTs synthesized at 10% duty cycle, exhibited high specific capacitance of 18.32 mF cm⁻² at a current density of 0.1 mA cm⁻² obtained from constant current charge–discharge measurements. This revealed that the specific capacitance possessed by Mn₂O₃/R-TNTs synthesized at 10% duty cycle was 6 times higher than bare R-TNTs.

Mn₂O₃ was coated onto reduced titania nanotubes by reverse pulse electrodeposition, showing smooth and homogenous deposits without covering the opening of the nanotubes.     

Evaluation of the use of direct oral anticoagulants for the management of heparin-induced thrombocytopenia

Journal of Thrombosis and Thrombolysis - Historically, treatment of heparin-induced thrombocytopenia (HIT) includes a non-heparin parenteral anticoagulant with bridging to warfarin once platelets...     

A two-stage immunoradiometric assay with 125I-staphylococcal protein A for the detection of antibodies and complement on human blood cells

A sensitive two-stage immunoradiometric assay (IRMA) using unlabeled specific antiglobulin sera followed by binding of radiolabeled staphylococcal protein A has been developed for detection of human IgG, IgM, IgA and complement C3 on human blood cells. In an experimental model system, purified human immunoglobulins (Ig) were coupled onto red blood cells, platelets, and leukocytes. The Ig-coated red blood cells were analyzed in parallel by three methods: the radioimmune antiglobulin test with radiolabeled anti-Ig; the radiolabeled staphyloccal protein A test, and the IRMA. Of the three methods evaluated, the latter was found to be sensitive and the easiest to perform. The applicability of the IRMA was established by investigating a group of 14 selected patients with autoimmune warm type hemolytic anemia. We observed that the IRMA detected cell-bound antibodies (IgG and/or IgM) in several cases where conventional assays yielded negative results.     

Donor leukocyte infusions for multiple myeloma

Donor leukocyte infusion (DLI) has well-documented activity in CML, but the role of DLI in other diseases is less well defined. To evaluate the strategy in multiple myeloma (MM) we evaluated 25 MM patients from 15 centers who were treated with DLI. Patients with persistent or recurrent disease after allogeneic BMT received DLI from the original marrow donor (23 matched related, one mismatched family, and one matched unrelated). Chemotherapy was given before DLI in three patients. Two of 22 patients responded completely to DLI alone and three patients responded to the combination of DLI and chemotherapy. Nine patients who had not had sufficient disease control after DLI were given additional DLIs; five of these patients had either complete (two) or partial (three) responses. Thirteen of 25 evaluable patients developed acute GVHD and 11 of 21 evaluable patients developed chronic GVHD; all responders developed GVHD. No patients developed post-DLI pancytopenia. Four patients had responses which lasted >1 year after DLI, three patients had responses which lasted <1 year, and three patients had ongoing responses but with follow-up <1 year. In conclusion, DLI has anti-myeloma activity but the strategy is limited by no response or short duration of response in a significant percentage of patients and by significant GVHD in the majority of the responders.     

Sex, age, and regional differences in L-type calcium current are important determinants of arrhythmia phenotype in rabbit hearts with drug-induced long QT type 2

In congenital and acquired long QT type 2, women are more vulnerable than men to torsade de pointes. In prepubertal rabbits (and children), the arrhythmia phenotype is reversed; however, females still have longer action potential durations than males. Thus, sex differences in K(+) channels and action potential durations alone cannot account for sex-dependent arrhythmia phenotypes. The L-type calcium current (I(Ca,L)) is another determinant of action potential duration, Ca(2+) overload, early afterdepolarizations (EADs), and torsade de pointes. Therefore, sex, age, and regional differences in I(Ca,L) density and in EAD susceptibility were analyzed in epicardial left ventricular myocytes isolated from the apex and base of prepubertal and adult rabbit hearts. In prepubertal rabbits, peak I(Ca,L) at the base was 22% higher in males than females (6.4+/-0.5 versus 5.0+/-0.2 pA/pF; P<0.03) and higher than at the apex (6.4+/-0.5 versus 5.0+/-0.3 pA/pF; P<0.02). Sex differences were reversed in adults: I(Ca,L) at the base was 32% higher in females than males (9.5+/-0.7 versus 6.4+/-0.6 pA/pF; P<0.002) and 28% higher than the apex (9.5+/-0.7 versus 6.9+/-0.5 pA/pF; P<0.01). Apex-base differences in I(Ca,L) were not significant in adult male and prepubertal female hearts. Western blot analysis showed that Ca(v)1.2alpha levels varied with sex, maturity, and apex-base, with differences similar to variations in I(Ca,L); optical mapping revealed that the earliest EADs fired at the base. Single myocyte experiments and Luo-Rudy simulations concur that I(Ca,L) elevation promotes EADs and is an important determinant of long QT type 2 arrhythmia phenotype, most likely by reducing repolarization reserve and by enhancing Ca(2+) overload and the propensity for I(Ca,L) reactivation.     

Serum leptin concentrations during severe protein-energy malnutrition: correlation with growth parameters and endocrine function

Circulating leptin, insulin, insulin-like growth factor-I (IGF-I), cortisol, and albumin concentrations and the growth hormone (GH) response to provocation were measured in 30 children with severe protein-energy malnutrition (PEM), 20 with marasmus and 10 with kwashiorkor, as well as 10 age-matched normal children (body mass index [BMI] >50th and <90th percentile for age and sex) and 10 prepubertal obese children (BMI >95th percentile for age and sex). Patients with PEM had a significantly lower BMI, midarm circumference (MAC), and skinfold thickness (SFT) compared with the age-matched control group. Basal cortisol and GH concentrations were significantly higher in the malnourished groups versus controls. Leptin and IGF-I were significantly lower in the marasmic and kwashiorkor groups versus normal children. Fasting insulin levels were significantly decreased in the kwashiorkor group compared with marasmic and normal children. The BMI correlated significantly with leptin (r = .77, P < .001), basal insulin (r = .61, P < .001), and IGF-I (r = .77, P < .001) and negatively with basal GH (r = -.52, P < .001). These findings suggest that during prolonged nutritional deprivation, the decreased energy intake, diminished subcutaneous fat mass, and declining insulin (and possibly IGF-I) concentration suppress leptin production. In support of this view, serum leptin levels were positively correlated with triceps, scapular, and abdominal SFT (r = .763, .75, and .744, respectively, P < .0001) in all of the children. Moreover, basal insulin and circulating IGF-I were correlated significantly with leptin concentrations (r = .47 and .62, respectively, P < .001). Basal levels of cortisol and GH were significantly elevated in the 2 groups with severe PEM. It is suggested that low leptin levels can stimulate the hypothalamic-pituitary-adrenal (HPA) axis and possibly the hypothalamic-pituitary-GH axis to maintain the high cortisol and GH levels necessary for effective lipolysis to ensure a fuel (fatty acids) supply for the metabolism of brain and peripheral tissue during nutritional deprivation. In summary, during prolonged PEM, the decreased synthesis of IGF-I and the low level of insulin and/or its diminished effect due to an insulin-resistant status in the presence of high circulating GH and cortisol levels ensure substrate diversion away from growth toward metabolic homeostasis. Leptin appears to be an important signal in the process of metabolic/endocrine adaptation to prolonged nutritional deprivation.     

Immediate effect of balloon valvuloplasty on hemostatic changes in mitral stenosis

This study was conducted to assess right and left atrial hemostatic function in patients with mitral stenosis (MS) and to investigate the immediate effect of balloon mitral valvuloplasty (BMV) on hemostatic function. BMV was performed in 28 patients with MS (age 29 +/- 8 years) who had sinus rhythm and no left atrial (LA) thrombus. Right and left atrial biochemical markers of platelet activity (platelet factor 4 [PF4] and B thromboglobulin [BTG]), coagulation (thrombin-antithrombin III complex [TAT]), and fibrinolytic activity (D-dimer) were measured before and 30 minutes after BMV. Right atrial levels of these markers were also measured in 20 control subjects. Compared with control subjects, patients with MS had higher right atrial levels of PF4 (30 +/- 15 vs 5 +/- 2 IU/ml), BTG (231 +/- 53 vs 30 +/- 8 IU/ml), TAT (7 +/- 4 vs 2 +/- 0.3 microg/L), and D-dimer (380 +/- 145 vs 160 +/- 35 ng/ml, p < 0.0001 in all). TAT levels were higher in the left atrium than in the right atrium of patients before BMV (8 +/- 4 vs 7 +/- 4 microg/L, p < 0.0001). BMV was successful (final mitral valve area > or = 1.5 cm2 and > or = 50% increase of the initial valve area) in all patients. There was a significant reduction of LA levels of PF4 (35 +/- 8 to 26 +/- 9 IU/ml, p < 0.0001), BTG (225 +/- 41 to 196 +/- 28 IU/ml, p < 0.001), and TAT (10 +/- 5 to 7 +/- 1 microg/L, p < 0.05) in the 16 patients with LA pressure < 10 mm Hg after BMV, whereas these markers were not reduced in the 12 patients with left atrial pressure > or = 10 mm Hg after BMV. These data indicate that platelet function, coagulation status, and fibrinolytic activity are increased regionally in the left atrium and in the systemic circulation in patients with MS and sinus rhythm in the absence of LA thrombus. Successful BMV induces a significant reduction of prethrombotic status in patients with low LA pressure after the procedure. Patients with high LA pressure after BMV maintain a high prethrombotic state and may be considered at an increased risk of thromboembolism after the procedure.     

Reversible posterior leukoencephalopathy in a patient with non-Hodgkin's lymphoma after treatment with CHOP

Reversible posterior leukoencephalopathy syndrome is a newly characterised and increasingly recognized clinico-radiologic syndrome. Underlying conditions that reportedly trigger this syndrome include hypertensive encephalopathy, eclampsia, renal failure, and immunosuppressive drug therapy with cyclosporine, tacrolimus and interferon alpha. We describe a 51-year-old woman with non-Hodgkin's lymphoma treated with conventional CHOP chemotherapy. Eight days after this treatment she developed severe headache, bilateral visual loss and focal seizures with secondary generalization. Neurologic examination showed confusion, cortical blindness, and left hemiparesis with hyperreflexia and sensory loss. A cranial T2-weighted magnetic resonance imaging revealed increased signal intensity in the occipital and frontal lobes in both hemispheres and right parietal lobe. A diagnosis of reversible posterior leukoencephalopathy was made. She presented a favourable outcome with conservative treatment with mannitol and phenytoin. A new cranial scanning showed nearly complete resolution of the abnormalities. To the best of our knowledge, this is the first case of reversible posterior leukoencephalopathy in a patient treated with standard-dose CHOP. In this patient, we confirm the theoretical pathophysiologic mechanisms suggested explaining how these drugs can cause the syndrome.     

Soluble and membranous endothelial protein C receptor in systemic lupus erythematosus patients: Relation to nephritis

Aim of the work

To investigate the role of endothelial protein C receptor (EPCR) (membrane and soluble forms) as a biomarker of lupus nephritis (LN) in systemic lupus erythematosus (SLE) patients and to study its relation to the prognosis and response to treatment.