Methylphenidate drug test (MPD) (cassette)

Conventional piperazine (PIP)-based nanofiltration (NF) membranes feature a high water flux and a high retention for divalent salt ions. However, it remains a challenge to obtain permselective NF membranes with high water permeance and a good selectivity for monovalent ions. In this work, a new m-phenylenediamine (MPD)-based thin-film composite (TFC) NF membrane with excellent desalination performance was developed by interfacial polymerization on a solvent resistant Kevlar nanofibrous hydrogel substrate. The desalination performance of the ANF TFC membrane shifted from reverse osmosis (RO) into NF with a facile solvent treatment. The decreased membrane surface roughness, reduced surface zeta potential and increased surface hydrophilicity after solvent treatment yielding a high water permeability (14.4 Lm(-2) h(-1) bar(-1)) for ANF TFC membrane, which is one order of magnitude higher than that of the pristine membrane and the hand-cast poly (m-phenylene isophthalamide) (PMIA) TFC membrane. The ANF TFC membrane showed an outstanding water-salt separation performance, with excellent rejections for multivalent salts (Na2SO4, 100%; MgSO4, 99.4%; MgCl2, 92.7%) and a high rejection for monovalent salt (NaCl, 80.3%), which is competitive with reference commercial membranes (NF90, NF270) tested in cross-flow filtration with 1000 mg L-1 salt solution at 6 bar, 25 degrees C. The newly developed TFC membrane was demonstrated to have great potential applications in water desalination, separation of organic compounds and dye wastewater treatment.

Background. Myocardial perfusion defects (MPD) due to coronary microvascular dysfunction is frequent in chronic Chagas cardiomyopathy (CCC) and may be involved with development of myocardial damage. We investigated whether MPD precedes left ventricular systolic dysfunction and tested the hypothesis that prolonged use of dipyridamole (DIPY) could reduce MPD in an experimental model of CCC in hamsters. Methods and results. We investigated female hamsters 6-months after T. cruzi infection (baseline condition) and control animals, divided into T. cruzi-infected animals treated with DIPY (CH 1 DIPY) or placebo (CH 1 PLB); and uninfected animals treated with DIPY (CO 1 DIPY) or placebo (CO 1 PLB). The animals were submitted to echocardiogram and rest SPECT-Sestamibi-Tc99m myocardial perfusion scintigraphy. Next, the animals were treated with DIPY (4 mg/kg bid, intraperitoneal) or saline for 30 days, and reevaluated with the same imaging methods. At baseline, the CH 1 PLB and CH 1 DIPY groups showed larger areas of perfusion defect (13.2 +/- 13.2% and 17.3 +/- 13.2%, respectively) compared with CO 1 PLB and CO 1 DIPY (3.8 +/- 2.2% e 3.5 +/- 2.7%, respectively), P <.05. After treatment, we observed: reduction of perfusion defects only in the CH 1 DIPY group (17.3 +/- 13.2% to 6.8 +/- 7.6%, P 5.001) and reduction of LVEF in CH 1 DIPY and CH 1 PLB groups (from 65.3 +/- 9.0% to 53.6 +/- 6.9% and from 69.3 +/- 5.0% to 54.4 +/- 8.6%, respectively, P <.001). Quantitative histology revealed greater extents of inflammation and interstitial fibrosis in both Chagas groups, compared with control group (P < .001), but no difference between Chagas groups (P >.05). Conclusions. The prolonged use of DIPY in this experimental model of CCC has reduced the rest myocardial perfusion defects, supporting the notion that those areas correspond to viable hypoperfused myocardium.