Mutations in the progranulin gene (PGRN) were identified as the causal mechanism underlying frontotemporal lobar degeneration (FTLD). Most of these mutations are predicted to create null alleles ...leading to a 50% loss of progranulin transcript.
Patients underwent clinical and neurologic examination at the Memory Clinic of the IRCCS S. Giovanni di Dio-Fatebenefratelli, Brescia, Italy. We enrolled affected (n = 6) and unaffected at risk members (n = 73) of families carrying the FTLD associated progranulin Leu271LeufsX10 mutation; additionally, we included subjects affected by sporadic/familial FTLD (n = 65), controls (n = 75), and a family carrying the tau P301L mutation. The presence of mutations in PGRN and MAPT genes was investigated by direct sequencing of exonic and flanking intronic regions. Progranulin plasma and CSF levels were measured using ELISA.
We demonstrated that progranulin protein is strongly reduced (up to 3.93-fold) both in plasma and CSF of affected and unaffected subjects carrying mutations in progranulin gene (PGRN Leu271LeufsX10 and Q341X). We established a plasma progranulin protein cutoff level of 74.4 ng/mL that identifies, with specificity and sensitivity of 100%, mutation carriers among unaffected subjects. In FTLD, values <or=110.9 ng/mL give a specificity of 92.8% and a sensitivity of 100% for PGRN mutations.
We propose the dosage of plasma progranulin as a useful tool for a quick and inexpensive large-scale screening of carriers of progranulin mutations and for monitoring future treatments that might boost the level of this protein.
This study delves into the adsorption behavior of both polar and non-polar molecules on silica surfaces, spanning a range from low coverage to full adsorption scenarios. Our results reveal that ...isopropanol exhibits a self-competitive adsorption mechanism on the surface. However, due to its thermodynamic stability, we anticipate fully covered pores under experimental conditions. In contrast, n-hexane demonstrates a substantial interaction with the hydrophilic substrate, displaying an enhanced adsorption effect whereby the adsorption gets stronger with an increasing number of molecules adhering to the pore’s surface. As a consequence, we predict a complete coverage of the pores under experimental conditions, accompanied by a discernible reduction in the mobility of these attached molecules. This observation carries significance, as alkanes are typically employed as probing molecules for measuring the geometric tortuosity of silica pores, assuming a reflective surface. Caution is advised, particularly for pores with thin diameters, in the order of a few molecular sizes.
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•Studied adsorption of polar and non-polar molecules on silica surfaces at different coverages.•Isopropanol’s adsorption is anti-cooperative but is expected to fully cover pores due to stability.•N-hexane interacts notably with hydrophilic substrates, showing stronger adsorption with more molecules.•The importance of using alkanes to measure geometric tortuosity of silica pores, especially thin ones is highlighted.
Diffusion Nuclear Magnetic Resonance experiments offer a means to determine the geometrical tortuosity of a porous matrix, assuming that the interaction between the confined fluid and the confining ...matrix is negligible. In this, alkanes play a crucial role as molecular probes for polar mesoporous systems, with silica being particularly relevant due to its wide range of technological applications. Despite their inherent hydrophobicity, NMR measurements reveal that alkane/silica interactions become significant when the pore diameter approaches the size of the molecules. This fact is clearly demonstrated through the examination of the longitudinal (T1) and transverse (T2) relaxation times of linear and cyclic alkanes confined within silica mesopores of mean pore sizes: 3, 6, and 15 nm. Noticeably, the interactions are practically negligible in 6 and 15 nm pores, but they become relevant in the smallest ones. T1-T2 correlation maps evidence that relaxation times are influenced by molecular length, shape, and pore diameter. These empirical results not only corroborate previous theoretical findings but also highlight the ratio T1/T2 as a valuable, rapid, and cost-effective experimental tool for assessing the feasibility of a given solvent as a molecular probe for determining geometrical tortuosity.
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The adsorption of water vapor in mesoporous TiO2 was studied by nuclear magnetic resonance (NMR) and multiscale molecular dynamics simulations. Three different water environments were distinguished ...and quantified: a first layer, where strongly bound water molecules exist at the inner surfaces; a second less structured layer but still with restricted mobility; and a bulk-like fraction of mobile water. The obtained NMR results can be explained in the framework of molecular dynamics simulations that give insight on the filling mechanisms in TiO2 nanoporous materials. For these highly hydrophilic materials, it is shown that adsorption isotherms may render a smaller effective pore size due to the presence of a layer of highly bound water. The synergistic combination of experimental NMR data and MD simulations renders a detailed analysis of the water dynamics inside the titania pore space.
Hyperpolarization has found many applications in Nuclear Magnetic Resonance (NMR) and Magnetic Resonance Imaging (MRI). However, its usage is still limited to the observation of relatively fast ...processes because of its short lifetimes. This issue can be circumvented by storing the hyperpolarization in a slowly relaxing singlet state. Symmetrical molecules hyperpolarized by Parahydrogen Induced Hyperpolarization (PHIP) provide straightforward access to hyperpolarized singlet states because the initial parahydrogen singlet state is preserved at almost any magnetic field strength. In these systems, which show a remarkably long (1)H singlet state lifetime of several minutes, the conversion of the NMR silent singlet state to observable magnetization is feasible due to the existence of singlet-triplet level anti-crossings. Here, we demonstrate that scaling the chemical shift Hamiltonian by rf irradiation is sufficient to transform the singlet into an observable triplet state. Moreover, because the application of one long rf pulse is only partially converting the singlet state, we developed a multiconversion sequence consisting of a train of long rf pulses resulting in successive singlet to triplet conversions. This sequence is used to measure the singlet state relaxation time in a simple way at two different magnetic fields. We show that this approach is valid for almost any magnetic field strength and can be performed even in the less homogeneous field of an MRI scanner, allowing for new applications of hyperpolarized NMR and MRI.
Wall shear stress (WSS) is an important stimulus in vascular remodelling and vascular lesion development. The current methods to assess and predict the risk associated with specific unsteady WSS ...consider the WSS mean values or the presence of reverse phases described by the oscillatory shear index. Recent evidence has shown that the accuracy of these methods is limited, especially with respect to the venous environment. Unsteady WSS are characterised by several features that may individually affect endothelial cells. Consequently, we assessed the effects of averaged WSS (TAWSS), temporal WSS gradient (TWSSG), maximum WSS (WSS peak) and reverse phase (OSI) by applying different WSS profiles to venous EC
in-vitro
, using a real-time controlled cone-and-plate cell-shearing device for 24 h. We found that TWSSG and WSS peak affect cell elongation and alignment respectively. We also found that the WSS waveforms with a peak of 1.5 Pa or higher significantly correlate with the induction of a protective phenotype. Cell phenotype induced by these high peak waveforms does not correlate to what is predicted by the hemodynamic indices currently used. The definition of reliable hemodynamic indices can be used to inform the computational models aimed at estimating the hemodynamic effects on vascular remodelling.
Aim
To evaluate the effectiveness of a solvent (eucalyptol) in improving filling material removal from canals connected by isthmuses, and the additional cleaning effect of a finishing instrument.
...Methodology
The mesial canals from 32 mandibular molars (Vertucci's type II morphology) were instrumented and filled with the single‐cone technique using Reciproc R25 gutta‐percha points (VDW, Munich, Germany) combined with Sealer 26 (Dentsply, Petrópolis, RJ, Brazil). Each root was then subjected to retreatment using the Mtwo instrument system (VDW), with or without a solvent (n = 16 per group). The volume of filling material in the canals was assessed by micro‐computed tomographic (micro‐CT) scans taken before and after retreatment. Canals with remnants of filling material received a supplementary procedure with the XP‐endo Finisher R instrument (FKG Dentaire, La Chaux‐de‐Fonds, Switzerland), with or without eucalyptol, and another micro‐CT scan was taken. All retreatment procedures were performed inside a cabinet under a controlled temperature (37 °C). Filling material removal was evaluated in the 5‐mm apical canal system for the canal+isthmus space or the isthmus alone. Statistical analyses were performed to compare the removal of filling material with and without eucalyptol, and after a supplementary approach with XP‐endo Finisher R. The level of significance was set at 5% for all statistical tests (P < 0.05).
Results
The amount of filling material removed from the canal+isthmus with Mtwo instruments was 83.2% when no solvent was used and 83.8% using the solvent (P > 0.05). When the isthmus area was evaluated separately, most specimens were associated with a reduction in the filling material, with no significant difference between the groups with or without using a solvent (P > 0.05). The supplementary step with XP‐endo Finisher R significantly improved removal of filling material from both canal and isthmus area (P < 0.05), regardless of the use of a solvent (P > 0.05).
Conclusion
The use of eucalyptol did not improve filling material removal from Vertucci's type II molar mesial canals and isthmuses. XP‐endo Finisher R significantly enhanced removal of filling material from the canals and isthmuses.
Several lines of evidence show that endogenous and exogenous cannabinoids modulate pain transmission at the spinal level through specific cannabinoid-1 (CB1) receptors. Since anatomical data ...concerning spinal CB1 receptors are rather contradictory, we studied the cellular and subcellular localizations of the CB1 receptors by immunocytochemistry. Results show a dual pre- and postsynaptic localization of CB1 receptors. Presynaptic receptors are evidenced by the labeling of (1) heterogeneous dorsal root ganglion neurons and (2) axons of Lissauer’s tract. Postsynaptic receptors are shown by the labeling of numerous interneurons in the outer part of lamina II. Double immunolabelings show that lamina II outer CB1 neurons, probably islet cells, may also contain GABA or nitric oxide synthase. Numerous CB1-containing neurons in lamina X are also immunostained with anti-nitric oxide synthase (NOS) antibody. Under the electron microscope, CB1 immunoreactivity is exclusively localized postsynaptically in both somatic and dendritic compartments. The absence of labeling on primary afferent axon terminals is discussed and compared to the absence of labeling on terminals or vesicle-containing dendrites of islet cells, where a presynaptic localization was expected according to data of the literature.
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•The problem of PASADENA signal cancelation in inhomogeneous field is tackled.•Signals are acquired with a CPMG echo train, thus preventing peak broadening.•Separation of PHIP from ...thermal signals is achieved.
The application of parahydrogen for the generation of hyperpolarization has increased continuously during the last years. When the chemical reaction that deposits the parahydrogen atoms into the target molecule is carried out following the PASADENA protocol an anti-phase signal is obtained, with a separation of the resonance lines of only a few Hz. Signal cancelation can be produced by line broadening due to magnetic field inhomogeneities or by the superposition with thermal signals. In this work we show that the acquisition of a J-spectrum has a double effect of enhancing spectral resolution and separating PHIP from thermal contributions even in systems where only a very small amount of hyperpolarization can be achieved.
Cannabinoid receptors and the endocannabinoids anandamide and 2‐arachidonoylglycerol have been suggested to regulate food intake in several animal phyla. Orthologs of the mammalian cannabinoid CB1 ...and CB2 receptors have been identified in fish. We investigated the presence of this endocannabinoid system in the brain of the goldfish Carassius auratus and its role in food consumption. CB1‐like immunoreactivity was distributed throughout the goldfish brain. The prosencephalon showed strong CB1‐like immunoreactivity in the telencephalon and the inferior lobes of the posterior hypothalamus. Endocannabinoids were detected in all brain regions of C. auratus and an anandamide‐hydrolysing enzymatic activity with features similar to those of mammalian fatty acid amide hydrolase was found. Food deprivation for 24 h was accompanied by a significant increase of anandamide, but not 2‐arachidonoylglycerol, levels only in the telencephalon. Anandamide caused a dose‐dependent effect on food intake within 2 h of intraperitoneal administration to satiated fish and significantly enhanced or reduced food intake at low (1 pg/g body weight) or intermediate (10 pg/g) doses, respectively, the highest dose tested (100 pg/g) being inactive. We suggest that endocannabinoids might variously contribute to adaptive responses to food shortage in fish.
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