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401.
Entropy of corneal nerve fibers distribution observed by laser scanning confocal microscopy: A noninvasive quantitative method to characterize the corneal innervation in Sjogren's syndrome patients
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Giorgio Bianciardi Maria Eugenia Latronico Claudio Traversi 《Microscopy research and technique》2015,78(12):1069-1074
Sjogren's syndrome (SS) is a progressive autoimmune condition mainly affecting the salivary and lacrimal glands with an incidence of primary SS between 1/100 and 1/1,000. SS implies an alteration in the epithelium and subepithelium innervation, with consequent reduction of corneal sensitivity. It is necessary to have noninvasive quantitative methods to characterize the status of the corneal nerve fibers of the patients in order to choose and follow the best therapy. Entropy (information dimension) of the nerve corneal fibers distribution observed by confocal microscopy was evaluated in patients with primary SS (n = 30, 6 males, 24 females, 21–81 years), diagnosed by biopsy of salivary gland and blood tests and in sex‐ age‐matched healthy subjects (n = 12). Corneal nerve fiber density, Langerhans cell count, and cell density in the nerve plexus images were also evaluated. In selected patients salivary gland atrophy degree was also evaluated. Nerve corneal distribution observed by confocal microscopy is fractal. Entropy of the corneal nerve distribution statistically distinguishes between SS patients and healthy subjects: patients present a lower value of information dimension of the corneal nerve fibers distribution than healthy individuals (P < 0.001). Percentage of grouped cases classified by entropy according to the subjects (selected patients vs. healthy) showed a 100% sensitivity and 96% specificity, P < 0.0001 with a low value of coefficient of variation among the individuals (6–7 times lower than the other morphometric indexes). Entropy correlated with the severity of the disease (salivary gland atrophy degree, P < 0.01). Evaluation of entropy of the corneal nerve distribution observed by a laser confocal microscopy appears to quantitatively and noninvasively characterize an aspect of the SS patients in relation to the recognition of an impairment of their ocular surface, giving us for the first time a method to objectively and precisely characterize the corneal innervation status in the SS patients. Microsc. Res. Tech. 78:1069–1074, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
402.
The effect of hydroxypropylmethylcellulose (HPMC) addition on a basic bread formulation is described. The effect of HPMC as bread improver and antistaling agent was analysed in terms of microstructure. Bread quality was assessed by physical parameters (volume, width/height ratio, moisture content and hardness), crumb grain structure (number of air cells, cells area and the ratio between cells area and total area) and sensory evaluation (appearance, aroma, taste and texture). Bread staling was determined by following both the hardness increase and the starch retrogradation during storage. The microstructure was analyzed by cryo scanning electron microscopy (cryo-SEM). The results confirm the ability of the HPMC for improving fresh bread quality and for delaying staling. The presence of HPMC decreased the hardening rate of the bread crumb and also retarded the amylopectin retrogradation. The microstructure analysis revealed the possible interaction between the HPMC and the bread constituents, which could partially explain the antistaling effect of this hydrocolloid. 相似文献
403.
The effects of electron-beam or gamma irradiation (doses of 1.5 kGy and 2.5 kGy of either one) on the microbial populations, respiratory activity and sensory characteristics of Tuber melanosporum packaged under modified atmospheres were monitored immediately after treatment, and subsequently every seven days during 35 days of storage at 4 °C. Treatments with 1.5 and 2.5 kGy reduced the total mesophilic aerobes counts respectively by 4.3 and 5.6 log cfu/g for electron-beam treatment, and by 6.4 and 6.6 log cfu/g for gamma irradiation. Other microbial groups studied (Pseudomonas genus, Enterobacteriaceae family, lactic acid bacteria, mesophilic aerobic spores, molds and yeasts) were not detected after the treatments. A decrease in the respiratory activity was detected in all the irradiated batches, indicating that the carbon dioxide levels were lower and the oxygen levels higher than those of the non-irradiated ones. Two species of yeasts, Candida sake and Candida membranifaciens var. santamariae, survived the irradiation treatments and became the dominant microbial populations with counts of up to 7.0 log cfu/g. The growth of these microorganisms was visible on the surface of irradiated truffles from day 21 onwards, affecting the flavor and the general acceptability of the ascocarps. Moreover, a watery exudate was detected in the treated truffles from the third week onwards, so the application of irradiation treatments in doses equal to or above 1.5 kGy did not preserve the quality characteristics of T. melanosporum truffles beyond 28 days. 相似文献
404.
The effect of frozen storage time of par-baked bread on the bread crumb and staling of bread obtained after thawing and full baking is described. The moisture content, hardness and retrogradation enthalpy of the amylopectin were determined in the par-baked bread and in the full baked bread after 7, 14, 28 and 42 days of frozen storage at −25 °C. In addition, the effect of frozen storage on the crumb microstructure was analyzed by cryo scanning electron microscopy (Cryo-SEM). The moisture content of both partially and full baked bread decreased with the time of frozen storage. The crumb hardness of the par-baked bread after different periods of frozen storage was kept constant, while that of their full baked counterpart increased with the time of frozen storage. In both types of breads, the enthalpy of amylopectin retrogradation did not vary with the period of frozen storage. The staling, measured as hardness increase and amylopectin retrogradation, increased along the frozen storage. The changes observed on the frozen par-baked bread after thawing were attributed to the damage of bread structures produced by the ice crystallization, and the microstructure study support that conclusion. 相似文献
405.
Magdaleno Caballero-Caballero José Luis Montes Bernabé Rafael Alavéz-Ramirez María Eugenia Silva Rivera 《Journal of Natural Fibers》2018,15(4):575-585
Adobe bricks, formed from raw clay, are used as construction materials since ancient times. Their main drawback is a low flexural and compressive strength. Agave bagasse is a waste material from the Mezcal production process. Angustifolia haw agave bagasse fiber was added to improve the properties of adobes. Adobe bricks were made with agave fibers ranging from 10 to 25 mm length and 0.25 to 1% concentration. At 1% concentration of agave, 25 mm long, the compressive and flexural strength are improved by 33% and 7.01%, fulfilling the requirements of Mexican construction regulation norm N-CMT-2-01-001/02 class C. 相似文献
406.
Elena Azzini Ilaria Peluso Federica Intorre Lorenzo Barnaba Eugenia Venneria Maria Stella Foddai Donatella Ciarapica Francesca Maiani Anna Raguzzini Angela Polito 《International journal of molecular sciences》2022,23(14)
Background: Inflammatory cytokine levels are associated with Non-Communicable Diseases (NCDs) and can be influenced by a person’s macronutrient profile. This work aims to evaluate the relationship between the compliance with the age-specific recommended protein intake and the levels of inflammatory markers related to the risk of NCDs. Methods: The study participants included 347 participants (119 men and 228 women), ages 18 to 86 years. Cardio-metabolic risk evaluations, including an assessment of the prevalence of Metabolic Syndrome, were performed. Leptin, IL-15, IL-6, and TNF-α levels were measured. Results: The adequacy of the total protein (TP) intake was lower in old people compared to individuals aged <60 years, and only few volunteers consumed the suggested 50% plant protein (PP) for a healthy and sustainable diet. A lower risk of NCDs with a PP consumption above at least 40% was observed only in old individuals. A differential effect on TNF-α and IL-6 was observed for both TP and PP intake by gender and age class, whereas for leptin and IL-15 only significant interactions among sex and the class of age were found. Conclusion: Although our data suggest that consuming more than 40% of PP can reduce the risk of NCDs, the effect of gender differences on cytokine levels should be considered in larger studies. 相似文献
407.
Miguel Alcoceba María García-lvarez Alejandro Medina Rebeca Maldonado Vernica Gonzlez-Calle María Carmen Chilln María Eugenia Sarasquete Marcos Gonzlez Ramn García-Sanz Cristina Jimnez 《International journal of molecular sciences》2022,23(10)
The MYD88 gene has a physiological role in the innate immune system. Somatic mutations in MYD88, including the most common L265P, have been associated with the development of certain types of lymphoma. MYD88L265P is present in more than 90% of patients with Waldenström’s macroglobulinemia (WM) and IgM monoclonal gammopathy of undetermined significance (IgM-MGUS). The absence of MYD88 mutations in WM patients has been associated with a higher risk of transformation into aggressive lymphoma, resistance to certain therapies (BTK inhibitors), and shorter overall survival. The MyD88 signaling pathway has also been used as a target for specific therapies. In this review, we summarize the clinical applications of MYD88 testing in the diagnosis, prognosis, follow-up, and treatment of patients. Although MYD88L265P is not specific to WM, few tumors present a single causative mutation in a recurrent position. The role of the oncogene in the pathogenesis of WM is still unclear, especially considering that the mutation can be found in normal B cells of patients, as recently reported. This may have important implications for early lymphoma detection in healthy elderly individuals and for the treatment response assessment based on a MYD88L265P analysis. 相似文献
408.
409.
Three out of four subtypes of arrestin proteins expressed in mammals self-associate, each forming oligomers of a distinct kind. Monomers and oligomers have different subcellular localization and distinct biological functions. Here we summarize existing evidence regarding arrestin oligomerization and discuss specific functions of monomeric and oligomeric forms, although too few of the latter are known. The data on arrestins highlight biological importance of oligomerization of signaling proteins. Distinct modes of oligomerization might be an important contributing factor to the functional differences among highly homologous members of the arrestin protein family. 相似文献
410.
Design,Synthesis and Evaluation of Novel Molecular Hybrids between Antiglaucoma Drugs and H2S Donors
Rosa Sparaco Valentina Citi Elisa Magli Alma Martelli Eugenia Piragine Vincenzo Calderone Giorgia Andreozzi Elisa Perissutti Francesco Frecentese Vincenzo Santagada Giuseppe Caliendo Beatrice Severino Angela Corvino Ferdinando Fiorino 《International journal of molecular sciences》2022,23(22)
Glaucoma is a group of eye diseases consisting of optic nerve damage with corresponding loss of field vision and blindness. Hydrogen sulfide (H2S) is a gaseous neurotransmitter implicated in various pathophysiological processes. It is involved in the pathological mechanism of glaucomatous neuropathy and exerts promising effects in the treatment of this disease. In this work, we designed and synthetized new molecular hybrids between antiglaucoma drugs and H2S donors to combine the pharmacological effect of both moieties, providing a heightened therapy. Brinzolamide, betaxolol and brimonidine were linked to different H2S donors. The H2S-releasing properties of the new compounds were evaluated in a phosphate buffer solution by the amperometric approach, and evaluated in human primary corneal epithelial cells (HCEs) by spectrofluorometric measurements. Experimental data showed that compounds 1c, 1d and 3d were the hybrids with the best properties, characterized by a significant and long-lasting production of the gasotransmitter both in the aqueous solution (in the presence of L-cysteine) and in the intracellular environment. Because, to date, the donation of H2S by antiglaucoma H2S donor hybrids using non-immortalized corneal cells has never been reported, these results pave the way to further investigation of the potential efficacy of the newly synthesized compounds. 相似文献