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31.
32.
The feasibility of injection molding was explored in the preparation of a novel capsular device for oral pulsatile/delayed delivery based on swellable/erodible polymers. For this purpose, a mold intended to be coupled with a bench-top injection-molding press was designed. This was expected to enable the preparation of matching capsule cap and body items within a single manufacturing cycle and the selection of differing shell thicknesses (300, 600, and 900 μm). Hydroxypropylcellulose (Klucel® EF, LF, and GF) was employed as the release-controlling polymer in admixture with polyethylene glycol 1500 (10%, w/w) as the plasticizer. After preliminary trials aimed at the setup of operating conditions, Klucel® EF and LF capsule shells with satisfactory technological properties were manufactured. The performance of capsular devices filled with a tracer drug powder was studied by means of a modified USP31 disintegration apparatus. Typical in vitro delayed release patterns were thereby obtained, with lag time increasing as a function of the wall thickness. A good correlation was found between the latter parameter and t 10%, i.e., the time to 10% release, for both polymer grades employed. On the basis of the overall results, the investigated technique was proven suitable for the manufacturing of an innovative pulsatile release platform. 相似文献
33.
Microtubule defects in mesenchymal stromal cells distinguish patients with Progressive Supranuclear Palsy 下载免费PDF全文
Alessandra Maria Calogero Mariele Viganò Silvia Budelli Daniela Galimberti Chiara Fenoglio Daniele Cartelli Lorenza Lazzari Petri Lehenkari Margherita Canesi Rosaria Giordano Graziella Cappelletti Gianni Pezzoli 《Journal of cellular and molecular medicine》2018,22(5):2670-2679
Progressive Supranuclear Palsy (PSP) is a rare neurodegenerative disease whose etiopathogenesis remains elusive. The intraneuronal accumulation of hyperphosphorylated Tau, a pivotal protein in regulating microtubules (MT), leads to include PSP into tauopathies. Pathological hallmarks are well known in neural cells but no word yet if PSP‐linked dysfunctions occur also in other cell types. We focused on bone marrow mesenchymal stromal cells (MSCs) that have recently gained attention for therapeutic interventions due to their anti‐inflammatory, antiapoptotic and trophic properties. Here, we aimed to investigate MSCs biology and to disclose if any disease‐linked defect occurs in this non‐neuronal compartment. First, we found that cells obtained from patients showed altered morphology and growth. Next, Western blotting analysis unravelled the imbalance in α‐tubulin post‐translational modifications and in MT stability. Interestingly, MT mass is significantly decreased in patient cells at baseline and differently changes overtime compared to controls, suggesting their inability to efficiently remodel MT cytoskeleton during ageing in culture. Thus, our results provide the first evidence that defects in MT regulation and stability occur and are detectable in a non‐neuronal compartment in patients with PSP. We suggest that MSCs could be a novel model system for unravelling cellular processes implicated in this neurodegenerative disorder. 相似文献
34.
35.
Alessandra Dalmasso Tiziana Civera Virginia Filipello Maria Teresa Bottero 《Molecular biology reports》2014,41(10):6329-6333
A multiplex primer-extension reaction (PER) assay, was specifically designed for the identification of ten Yersinia species. The assay, directed towards the tufA (elongation factor Tu) gene, was tested on a total of 42 samples representing Yersinia species and non-Yersinia species. The primers used in the preliminary PCR, designed in highly conserved regions upstream and downstream of the diagnosis sites, successfully amplified a 587 bp fragment. The diagnosis sites were simultaneously interrogated using a multiplex PER and the results were confirmed by fragment sequencing. The proposed test provides an appropriate tool to monitor the presence of Yersinia spp. in food samples and to evaluate the potential hazard for consumers. 相似文献
36.
Mònica Estrada Clara Navarrete Sønke Møller Alessandra Procentese José L. Martínez 《Microbial biotechnology》2023,16(2):404-417
The dairy industry processes vast amounts of milk and generates high amounts of secondary by-products, which are still rich in nutrients (high Chemical Oxygen Demand (COD) and Biochemical Oxygen Demand (BOD) levels) but contain high concentrations of salt. The current European legislation only allows disposing of these effluents directly into the waterways with previous treatment, which is laborious and expensive. Therefore, as much as possible, these by-products are reutilized as animal feed material and, if not applicable, used as fertilizers adding phosphorus, potassium, nitrogen, and other nutrients to the soil. Finding biological alternatives to revalue dairy by-products is of crucial interest in order to improve the utilization of dry dairy matter and reduce the environmental impact of every litre of milk produced. Debaryomyces hansenii is a halotolerant non-conventional yeast with high potential for this purpose. It presents some beneficial traits – capacity to metabolize a variety of sugars, tolerance to high osmotic environments, resistance to extreme temperatures and pHs – that make this yeast a well-suited option to grow using complex feedstock, such as industrial waste, instead of the traditional commercial media. In this work, we study for the first time D. hansenii's ability to grow and produce a recombinant protein (YFP) from dairy saline whey by-products. Cultivations at different scales (1.5, 100 and 500 ml) were performed without neither sterilizing the medium nor using pure water. Our results conclude that D. hansenii is able to perform well and produce YFP in the aforementioned salty substrate. Interestingly, it is able to outcompete other microorganisms present in the waste without altering its cell performance or protein production capacity. 相似文献
37.
Stefano Biffani Corrado Dimauro Nicolò Macciotta Attilio Rossoni Alessandra Stella Filippo Biscarini 《遗传、选种与进化》2015,47(1)
Background
SNP (single nucleotide polymorphisms) genotype data are increasingly available in cattle populations and, among other things, can be used to predict carriers of specific haplotypes. It is therefore convenient to have a practical statistical method for the accurate classification of individuals into carriers and non-carriers. In this paper, we present a procedure combining variable selection (i.e. the selection of predictive SNPs) and linear discriminant analysis for the identification of carriers of a haplotype on BTA19 (Bos taurus autosome 19) known to be associated with reduced cow fertility. A population of 3645 Brown Swiss cows and bulls genotyped with the 54K SNP-chip was available for the analysis.Results
The overall error rate for the prediction of haplotype carriers was on average very low (∼≤1%). The error rate was found to depend on the number of SNPs in the model and their density around the region of the haplotype on BTA19. The minimum set of SNPs to still achieve accurate predictions was 5, with a total test error rate of 1.59.Conclusions
The paper describes a procedure to accurately identify haplotype carriers from SNP genotypes in cattle populations. Very few misclassifications were observed, which indicates that this is a very reliable approach for potential applications in cattle breeding. 相似文献38.
Paolo Ascenzi Loris Leboffe Alessandra di Masi Viviana Trezza Gabriella Fanali Magda Gioia Massimo Coletta Mauro Fasano 《PloS one》2015,10(3)
The hydrolysis of 4-nitrophenyl esters of hexanoate (NphOHe) and decanoate (NphODe) by human serum albumin (HSA) at Tyr411, located at the FA3-FA4 site, has been investigated between pH 5.8 and 9.5, at 22.0°C. Values of K
s, k
+2, and k
+2/K
s obtained at [HSA] ≥ 5×[NphOXx] and [NphOXx] ≥ 5×[HSA] (Xx is NphOHe or NphODe) match very well each other; moreover, the deacylation step turns out to be the rate limiting step in catalysis (i.e., k
+3 << k
+2). The pH dependence of the kinetic parameters for the hydrolysis of NphOHe and NphODe can be described by the acidic pK
a-shift of a single amino acid residue, which varies from 8.9 in the free HSA to 7.6 and 7.0 in the HSA:NphOHe and HSA:NphODe complex, respectively; the pK>a-shift appears to be correlated to the length of the fatty acid tail of the substrate. The inhibition of the HSA-Tyr411-catalyzed hydrolysis of NphOHe, NphODe, and 4-nitrophenyl myristate (NphOMy) by five inhibitors (i.e., diazepam, diflunisal, ibuprofen, 3-indoxyl-sulfate, and propofol) has been investigated at pH 7.5 and 22.0°C, resulting competitive. The affinity of diazepam, diflunisal, ibuprofen, 3-indoxyl-sulfate, and propofol for HSA reflects the selectivity of the FA3-FA4 cleft. Under conditions where Tyr411 is not acylated, the molar fraction of diazepam, diflunisal, ibuprofen, and 3-indoxyl-sulfate bound to HSA is higher than 0.9 whereas the molar fraction of propofol bound to HSA is ca. 0.5. 相似文献
39.
Amanda Carroll-Portillo Judy L. Cannon Joost te Riet Anna Holmes Yuko Kawakami Toshiaki Kawakami Alessandra Cambi Diane S. Lidke 《The Journal of cell biology》2015,210(5):851-864
Mast cells (MCs) produce soluble mediators such as histamine and prostaglandins that are known to influence dendritic cell (DC) function by stimulating maturation and antigen processing. Whether direct cell–cell interactions are important in modulating MC/DC function is unclear. In this paper, we show that direct contact between MCs and DCs occurs and plays an important role in modulating the immune response. Activation of MCs through FcεRI cross-linking triggers the formation of stable cell–cell interactions with immature DCs that are reminiscent of the immunological synapse. Direct cellular contact differentially regulates the secreted cytokine profile, indicating that MC modulation of DC populations is influenced by the nature of their interaction. Synapse formation requires integrin engagement and facilitates the transfer of internalized MC-specific antigen from MCs to DCs. The transferred material is ultimately processed and presented by DCs and can activate T cells. The physiological outcomes of the MC–DC synapse suggest a new role for intercellular crosstalk in defining the immune response. 相似文献
40.
Toffanello ED Perissinotto E Sergi G Zambon S Musacchio E Maggi S Coin A Sartori L Corti MC Baggio G Crepaldi G Manzato E 《PloS one》2012,7(4):e34950