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Ficoll and dextran vs. globular proteins as probes for testing glomerular permselectivity: effects of molecular size, shape, charge, and deformability.

Polydisperse mixtures of dextran or Ficoll have been frequently used as molecular probes for studies of glomerular permselectivity because they are largely inert and not processed (reabsorbed) by the proximal tubules. However, dextrans are linear, flexible molecules, which apparently are hyperpermeable across the glomerular barrier. By contrast, the Ficoll molecule is almost spherical. Still, ther

Gauge fields, point interactions and few-body problems in one dimension

Point interactions for the second derivative operator in one dimension are studied. Every operator from this family is described by the boundary conditions which include a 2 x 2 real matrix with the unit determinant and a phase. The role of the phase parameter leading to unitarily equivalent operators is discussed in the present paper. In particular, it is shown that the phase parameter is not red

Cross layer routing and media access control with channel dependant forwarding in wireless ad-hoc networks

Wireless ad hoc networks have the last 10 years gained a lot of attention within the research community. A wireless ad hoc network is a special type of wireless network where nodes are typically mobile and doesn’t rely on any fixed infrastructure to operate correctly. Much work has been done on developing robust and stable routing algorithms that consider the dynamic nature of an ad hoc network: n

Transfection of HeLa-cells with pEGFP plasmid power-assisted by impedance electroporation

Bioimpedance spectrometry was applied to study cell viability and pEGFP plasmid-transfection efficiency in electroporation (EP) of 20,000 HeLa cells with 0.3 mu g DNA in 90 mu l low conductivity 0.32 M sucrose medium of pH 7.5. Monopolar rectangular pulses, of field strength 75 V/mm, and pulse length 0.1 ms were applied in 1-16 repetitions with a 10-sec pause interval between pulses. Surviving cel

LES of supersonic combustion in a scramjet engine model

In this study, Large Eddy Simulation (LES) has been used to examine supersonic flow and combustion in a model scramjet combustor. The LES model is based on an unstructured finite volume discretization, using total variational diminishing flux reconstruction, of the filtered continuity, momentum, enthalpy, and passive/reactive scalar equations, used to describe the combustion process. The configura

CSF Biomarkers for Alzheimer's Disease: Levels of beta-Amyloid, Tau, Phosphorylated Tau Relate to Clinical Symptoms and Survival.

Cerebrospinal fluid (CSF) samples from 21 patients with a clinical diagnosis of Alzheimer's disease (AD) participating in a 5-year treatment study with the choline esterase inhibitor tacrin were retrospectively analyzed for the contents of beta-amyloid (Abeta42), total tau (T-tau) and phosphorylated tau (P-tau). A significant positive correlation between the level of P-tau and the number of sympto

Dopamine released from 5-HT terminals is the cause of L-DOPA-induced dyskinesia in parkinsonian rats.

n patients with Parkinson's disease, the therapeutic efficacy of L-DOPA medication is gradually lost over time, and abnormal involuntary movements, dyskinesias, gradually emerge as a prominent side-effect in response to previously beneficial doses of the drug. Here we show that dyskinesia induced by chronic L-DOPA treatment in rats with 6-hydroxydopamine-induced lesions of the nigrostriatal dopami

Alveolar accumulation of fibronectin and hyaluronan precedes bleomycin-induced pulmonary fibrosis in the rat

The development of bleomycin-induced pulmonary fibrosis in rats was studied over a period of 30 days after an intratracheal instillation of bleomycin. Fibronectin was visualized in histological sections and quantified in bronchoalveolar lavage fluid (BALF) and related to simultaneous measurements of hyaluronan, collagen and albumin in BALF and/or lung tissue extracts. An increase in BALF fibronect

Modeling of protein breakthrough performance in cryogel columns by taking into account the overall axial dispersion.

A model considering the overall axial dispersion for describing protein adsorption and breakthrough in monolithic cryogel beds has been developed. The microstructure of cryogels was characterized by tortuous capillaries with a normal diameter distribution but a constant pore wall thickness. The axial dispersion within cryogel columns was described by using the overall axial dispersion coefficient,

Desmin filaments influence myofilament spacing and lateral compliance of slow skeletal muscle fibres.

Intermediate filaments composed of desmin interlink Z-disks and sarcolemma in skeletal muscle. Depletion of desmin results in lower active stress of smooth, cardiac, and skeletal muscles. Structural functions of intermediate filaments in fast (psoas) and slow (soleus) skeletal muscle were examined using x-ray diffraction on permeabilized muscle from desmin-deficient mice (Des–/–) and controls (Des

Synthesis, structure, and reactivity of arylfluoro platinum(II) complexes.

Complexes of the type trans-[PtPhFL2], where L = PPh3 (4), PMe2Ph (5), were synthesized. Complex 4 was characterized by X-ray crystallography. The equilibrium constant for the substitution of the fluoride trans to phenyl in 4 by Cl- and I- was determined, and the stability sequence follows the normal trend seen in "soft" metal centers: i.e., the Pt has a preference for the halide in the order I >

Post-juvenile and post-breeding moult of Savi’s Warblers Locustella luscinioides in Portugal.

We describe the sequence and extent of the complex and little understood post-juvenile and post-breeding moults of Savi’s Warblers Locustella luscinioides. In contrast to previous studies, the post-juvenile moult occurred in at least 44% of the birds, 5% of which moulted some or all tertials and greater coverts. The timing of overlap between the filling and the post-juvenile moults, and the fact t

Tobacco peroxidase as a new reagent for amperometric biosensors

The results of testing a new enzyme, anionic tobacco peroxidase (TOP), in various amperometric biosensors are summarized. The biochemical and electrochemical properties of the enzyme are briefly characterized. As compared to the commonly used cationic peroxidase from horseradish roots, TOP exhibits a wider optimum stability pH range, higher stability to inactivation with hydrogen peroxide, and hig

High-resolution QTL Analysis Reveals Multiple Diabetes Susceptibility Loci Mapped to Intervals less than 800-kb in the Species Conserved Niddm1i of the GK Rat.

Niddmli, a 16-Mb locus within the major diabetes QTL in the diabetic GK rat, causes impaired glucose tolerance in the congenic NIDDM11 strain. Niddm1i is homologous to both human and mouse regions linked with type 2 diabetes susceptibility. We employed multiple QTL analyses of congenic F2 progeny selected for one recombination event within Niddm1i combined with characterization of subcongenic stra

The Pegomya maculata species group (Diptera Anthomyiidae) in Europe, with description of a new species

The number of species in the Pegomya maculata species group is raised from three to four with the description of a new, Holarctic species, P. grahami sp. nov. The other species, P. maculata Stein, P. atricauda Ringdahl and P. macrophthalma Griffiths, are redescribed. The number of species in Europe is raised from two to four. Two species, P. grahami (previously recorded as P. maculata) and P. macr

Differentiation of the RN33B Cell Line into Forebrain Projection Neurons after Transplantation into the Neonatal Rat Brain.

The rat neural cell line RN33B has a remarkable ability to undergo region-specific neuronal differentiation after transplantation into the CNS. To further study its neurogenic properties in vivo, we used a recombinant lentiviral vector to genetically label the cells with the Green Fluorescent Protein (GFP) gene before implantation into the striatum/cortex, hippocampus, or mesencephalon of newborn

The isolation, primacy, and recency effects predicted by an adaptive LTD/LTP threshold in postsynaptic cells

An item that stands out (is isolated) from its context is better remembered than an item consistent with the context. This isolation effect cannot be accounted for by increased attention, because it occurs when the isolated item is presented as the first item, or by impoverished memory of nonisolated items, because the isolated item is better remembered than a control list consisting of equally di

Cerebral perfusion in the elderly with nocturnal blood pressure fall

Cerebrovascular disease may be linked with vascular autoregulation in aging. The aim of this study was to examine relation between nocturnal blood pressure (BP) fall and cerebral blood flow (CBF) changes in elderly men. The prospective 'Men born in 1914' cohort study has been in progress since 1968 and included 809 subjects. After 14 years from the last follow up, 97 subjects reached the age of 82