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1.
Plant Cell ; 30(12): 2943-2958, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30361236

RESUMO

Although several resurrection plant genomes have been sequenced, the lack of suitable dehydration-sensitive outgroups has limited genomic insights into the origin of desiccation tolerance. Here, we utilized a comparative system of closely related desiccation-tolerant (Lindernia brevidens) and -sensitive (Lindernia subracemosa) species to identify gene- and pathway-level changes associated with the evolution of desiccation tolerance. The two high-quality Lindernia genomes we assembled are largely collinear, and over 90% of genes are conserved. L. brevidens and L. subracemosa have evidence of an ancient, shared whole-genome duplication event, and retained genes have neofunctionalized, with desiccation-specific expression in L. brevidens Tandem gene duplicates also are enriched in desiccation-associated functions, including a dramatic expansion of early light-induced proteins from 4 to 26 copies in L. brevidens A comparative differential gene coexpression analysis between L. brevidens and L. subracemosa supports extensive network rewiring across early dehydration, desiccation, and rehydration time courses. Many LATE EMBRYOGENESIS ABUNDANT genes show significantly higher expression in L. brevidens compared with their orthologs in L. subracemosa Coexpression modules uniquely upregulated during desiccation in L. brevidens are enriched with seed-specific and abscisic acid-associated cis-regulatory elements. These modules contain a wide array of seed-associated genes that have no expression in the desiccation-sensitive L. subracemosa Together, these findings suggest that desiccation tolerance evolved through a combination of gene duplications and network-level rewiring of existing seed desiccation pathways.


Assuntos
Duplicação Gênica/genética , Lamiaceae/genética , Proteínas de Plantas/genética , Dessecação , Regulação da Expressão Gênica de Plantas/genética
2.
Neurol Sci ; 41(2): 365-372, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31654362

RESUMO

OBJECTIVES: Anti-myelin-associated glycoprotein (MAG) antibody is associated with clinically heterogeneous polyneuropathies. Our purpose was to compare neuropathy phenotypes identified by different anti-MAG tests' results. METHODS: Cohort study: Sera from 40 neuropathy anti-MAG EIA positive patients were tested for anti-MAG by Western blot (WB), for anti-peripheral nerve myelin (PNM) on monkey nerve by immunofluorescence assay (IFA), and for anti-HNK1 on rat CNS slices by IFA. Anti-sulfatide antibodies, for comparison, were also tested by EIA. RESULTS: Among 40 anti-MAG EIA positive sera, 85% also had anti-PNM IFA reactivity and 67.5% bind HNK1 on rat CNS. Anti-HNK1 positive patients had the classical predominantly distal acquired demyelinating symmetric (DADS) neuropathy with a benign course, while anti-PNM positive but anti-HNK1 negative patients had predominantly axonal neuropathy with a high frequency of anti-sulfatide reactivity and the worst long-term prognosis. Anti-MAG EIA positive patients without anti-PNM or anti-HNK1 IFA reactivity had a CIDP-like polyneuropathy. CONCLUSION: Different methods to test for anti-MAG antibodies identify different clinical and electrophysiological findings, as well as long-term outcome. HNK1 reactivity is the strongest marker of DADS.


Assuntos
Autoanticorpos/sangue , Imunoglobulina M/imunologia , Glicoproteína Associada a Mielina/metabolismo , Doenças do Sistema Nervoso Periférico/imunologia , Adolescente , Animais , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Bainha de Mielina/imunologia , Glicoproteína Associada a Mielina/imunologia , Doenças do Sistema Nervoso Periférico/tratamento farmacológico , Polineuropatias/imunologia , Ratos , Adulto Jovem
3.
Graefes Arch Clin Exp Ophthalmol ; 253(2): 277-86, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25363654

RESUMO

PURPOSE: The purpose was to investigate the early modifications induced by collagen cross-linking by iontophoresis of riboflavin (ionto-CXL) in ex vivo human corneas by evaluating different protocols of UVA irradiation. METHODS: In this experimental study 46 ex vivo human corneas obtained from the Eye Bank of Mestre (Italy) were divided in different groups: six were utilized as control (CTL); eight were treated with ionto-CXL at 3 mW/cm(2) power for 30 min (I-3); eight were treated with ionto-CXL at 10 mW/cm(2) for 9 min (I-10); eight were treated with iontophoretic delivery of riboflavin only (I-0); eight were treated with the standard CXL at 3 mW/cm(2) for 30 min (S-3); and eight were treated with CXL at 10 mW/cm(2) for 9 min (S-10). All samples were evaluated by haematoxylin-eosin staining and immunohistochemical analysis using different markers (Connexin 43, CD34, Collagen I, TUNEL assay). Western blot analysis, utilizing Bax and Ki67 primary antibodies, for detection of keratocyte apoptosis and proliferation, respectively, was also performed. RESULTS: No endothelial damage was evidenced in the treated groups. In I-10 corneas the epithelial layers were not always well-preserved. Anterior stroma showed an uneven distribution and numerical reduction of keratocytes as well as increased apoptosis; a reduced subepithelial interweaving of collagen I fibers was observed. In S-3 and S-10 the changes induced by treatments were similar to I-10. I-3 and I-0 showed no significant changes with respect to the control group. CONCLUSIONS: In the ionto-CXL at 10 mW/cm(2) group occurred the main morphological and biomolecular changes. This experimental study suggests that iontophoresis can be considered a non-invasive potential delivery tool for riboflavin penetration in corneal stroma during CXL.


Assuntos
Colágeno/metabolismo , Substância Própria/metabolismo , Reagentes de Ligações Cruzadas , Iontoforese/métodos , Fármacos Fotossensibilizantes/uso terapêutico , Riboflavina/uso terapêutico , Antígenos CD34/metabolismo , Apoptose , Western Blotting , Colágeno Tipo I/metabolismo , Conexina 43/metabolismo , Ceratócitos da Córnea/metabolismo , Ceratócitos da Córnea/patologia , Humanos , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Antígeno Ki-67/metabolismo , Doadores de Tecidos , Proteína X Associada a bcl-2/metabolismo
4.
Sci Total Environ ; 888: 164238, 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37196946

RESUMO

The use of petroleum-based plastic has led to its accumulation in the environment, with negative impacts on the ecosystem and the biota. Polyhydroxyalkanoates (PHAs), biobased and biodegradable plastics produced by microbes, have many commercial applications, however their high production cost means they cannot yet compete with traditional plastics. At the same time, the problem of the growing human population implies that improved crop production is needed to avoid malnutrition. Biostimulants enhance plant growth and have the potential to improve agricultural yields; they can be obtained from biological feedstock, including microbes. Therefore, there is scope for coupling the production of PHAs with that of biostimulants, making the process more cost-efficient and minimizing by-products generation. In this work, low-value agro-zoological residues were processed to obtain PHA-storing bacteria via acidogenic fermentation; PHAs destined for the bioplastic market were extracted, and the protein-rich by-products were turned into protein hydrolysates using different treatment methods, assessing their biostimulant effects in growth trials with tomato and cucumber plants. The results indicate that the best hydrolysis treatment, realizing the highest amount of organic nitrogen (6.8 gN-org/L) while achieving the best PHA recovery (63.2 % gPHA/gTS), is obtained with strong acids. All the protein hydrolysates were effective in improving either roots or leaf development, with various results, depending on the species and the growth method. The acid hydrolysate was the most effective treatment to enhance the development of shoots (21 % increase compared to the control) and roots (16 % increase for the dry weight and 17 % for main root length) of hydroponically-grown cucumber plants, while pot-grown tomatoes, biostimulated via foliar spray, developed bigger shoots (up to 41 %) with the hydrolysate obtained from the alkaline treatment. These preliminary results indicate that simultaneous production of PHAs and biostimulants is feasible, and that commercialization could be achievable given the expected reduction in production costs.


Assuntos
Plásticos Biodegradáveis , Poli-Hidroxialcanoatos , Humanos , Poli-Hidroxialcanoatos/metabolismo , Ecossistema , Hidrolisados de Proteína/metabolismo , Bactérias/metabolismo
5.
Opt Lett ; 37(19): 3948-50, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23027241

RESUMO

We investigated the interaction of an intense laser radiation with colloidal solutions containing CdSe/ZnS core shell quantum dots (QDs; mean size 3.4 nm), fullerene C(60), and Perylene. These materials would give rise to the photoinduced electron transfer and charge separation on the QDs and thus the optical limiting effect. Results confirm the intended aim, obtained by means of intermediate metastable products of reversible photochemical reactions, i.e., ion radicals of hybrid systems containing semiconductor nanoparticles.

6.
J Agric Food Chem ; 70(36): 11201-11211, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36039940

RESUMO

Protein hydrolysates (PHs) are plant biostimulants consisting of oligopeptides and free amino acids exploited in agriculture to increase crop productivity. This work aimed to fractionate a commercial collagen-derived protein hydrolysate (CDPH) according to the molecular mass of the peptides and evaluate the bioactivity of different components. First, the CDPH was dialyzed and/or filtrated and analyzed on maize, showing that smaller compounds were particularly active in stimulating lateral root growth. The CDPH was then fractionated through fast protein liquid chromatography and tested on in vitro grown tomatoes proving that all the fractions were bioactive. Furthermore, these fractions were characterized by liquid chromatography-electrospray ionization-tandem mass spectrometry revealing a consensus sequence shared among the identified peptides. Based on this sequence, a synthetic peptide was produced. We assessed its structural similarity with the CDPH, the collagen, and polyproline type II helix by comparing the respective circular dichroism spectra and for the first time, we proved that a signature peptide was as bioactive as the whole CDPH.


Assuntos
Peptídeos , Hidrolisados de Proteína , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Colágeno/química , Peptídeos/química , Hidrolisados de Proteína/química
7.
Front Plant Sci ; 12: 600623, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33633760

RESUMO

Protein hydrolysates (PHs) are a class of plant biostimulants used in the agricultural practice to improve crop performance. In this study, we have assessed the capacity of a commercial PH derived from bovine collagen to mitigate drought, hypoxic, and Fe deficiency stress in Zea mays. As for the drought and hypoxic stresses, hydroponically grown plants treated with the PH exhibited an increased growth and absorption area of the roots compared with those treated with inorganic nitrogen. In the case of Fe deficiency, plants supplied with the PH mixed with FeCl3 showed a faster recovery from deficiency compared to plants supplied with FeCl3 alone or with FeEDTA, resulting in higher SPAD values, a greater concentration of Fe in the leaves and modulation in the expression of genes related to Fe. Moreover, through the analysis of circular dichroism spectra, we assessed that the PH interacts with Fe in a dose-dependent manner. Various hypothesis about the mechanisms of action of the collagen-based PH as stress protectant particularly in Fe-deficiency, are discussed.

8.
Histol Histopathol ; 32(11): 1207-1221, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28485004

RESUMO

Investigations on animal models demonstrated that changes of sialic acid (SA) expression, particularly the polymeric form, in the skeletal muscle during embryonic and post-natal development seem to be related to muscle differentiation and functionality onset. The aim of this study was to evaluate the monomeric and polymeric SA expression in human skeletal muscle during early stages of fetal development, when important morphofunctional events occur. Specimens of fetal skeletal muscle from limb, between 9 and 12 weeks of gestation (wg), were obtained from 19 pregnant women. To investigate some morphofunctional features occurring during this development period, haematoxylin-eosin staining, tunel assay and immunohistochemistry for connexin-43 (Cx43) and parvalbumin were performed. SA expression and characterization was evaluated using lectin histochemistry (MAA, SNA, PNA, SBA, DBA), associated with enzymatic and chemical treatments. Polysialic acid (PSA) expression was also evaluated using immunohistochemistry. The results showed apoptotic myotubes between 9 and 10.5 wg, disappearing from 11 wg; Cx43 was more abundant in myotubes/myoblasts between 9 and 9.5 wg, decreasing and/or disappearing from 10 wg and parvalbumin was present in myotubes between 10 and 10.5 wg. PSA was revealed in myotubes/myoblasts from 9 to 10.5 wg; from 11 wg it was reduced or disappeared. Monomeric SA appeared in myotubes/myoblasts from 10 wg, increasing successively; acetylated SA was present from 11 wg. These findings demonstrated that changes in expression of various types of SA, occurring in human fetal skeletal muscle during early development, seem to be related to some morphofunctional aspects distinctive of this organogenesis crucial period.


Assuntos
Desenvolvimento Muscular/fisiologia , Músculo Esquelético/embriologia , Ácido N-Acetilneuramínico/biossíntese , Feto , Humanos
9.
Front Cell Neurosci ; 11: 339, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29163051

RESUMO

The degeneration of cholinergic neurons of the nucleus basalis of Meynert (NBM) in the basal forebrain (BF) is associated to the cognitive decline of Alzheimer's disease (AD) patients. To date no resolutive therapies exist. Cell-based replacement therapy is a strategy currently under consideration, although the mechanisms underlying the generation of stem cell-derived NBM cholinergic neurons able of functional integration remain to be clarified. Since fetal brain is an optimal source of neuronal cells committed towards a specific phenotype, this study is aimed at isolating cholinergic neurons from the human fetal NBM (hfNBMs) in order to study their phenotypic, maturational and functional properties. Extensive characterization confirmed the cholinergic identity of hfNBMs, including positivity for specific markers (such as choline acetyltransferase) and acetylcholine (Ach) release. Electrophysiological measurements provided the functional validation of hfNBM cells, which exhibited the activation of peculiar sodium (INa) and potassium (IK) currents, as well as the presence of functional cholinergic receptors. Accordingly, hfNBMs express both nicotinic and muscarinic receptors, which were activated by Ach. The hfNBMs cholinergic phenotype was regulated by the nerve growth factor (NGF), through the activation of the high-affinity NGF receptor TrkA, as well as by 17-ß-estradiol through a peculiar recruitment of its own receptors. When intravenously administered in NBM-lesioned rats, hfNBMs determined a significant improvement in memory functions. Histological examination of brain sections showed that hfNBMs (labeled with PKH26 fluorescent dye prior to administration) reached the damaged brain areas. The study provides a useful model to study the ontogenetic mechanisms regulating the development and maintenance of the human brain cholinergic system and to assess new lines of research, including disease modeling, drug discovery and cell-based therapy for AD.

10.
Endocrinology ; 146(10): 4321-30, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15994351

RESUMO

FNC-B4 neuroblasts that express both neuronal and olfactory markers have been established and cloned. These cells express GnRH and both the endothelin-1 (ET-1) gene and protein and respond in a migratory manner to GnRH in a dose-dependent manner. Previous research has shown that FNC-B4 cells produce and respond to ET-1 by regulating the secretion of GnRH through endothelin type A receptors and by stimulating their proliferation through endothelin type B (ETB) receptors. In this study, we found that FNC-B4 cells are able to migrate in response to ET-1 through the involvement of ETB receptors. Combined immunohistochemical and biochemical analyses showed that ET-1 triggered actin cytoskeletal remodeling and a dose-dependent increase in migration (up to 6-fold). Whereas the ETB receptor antagonist (B-BQ788) blunted the ET-1-induced effects, the ETA receptor antagonist (A-BQ123) did not. Moreover, we observed that FNC-B4 cells were independently and selectively stimulated by ET-1 and GnRH. We suggest that ET-1, through ETB receptor activation, may be required to maintain an adequate proliferative stem cell pool in the developing olfactory epithelium and the subsequent commitment to GnRH neuronal migratory pattern. The coordinate interaction between ET receptors and GnRH receptor participates in the fully expressed GnRH-secreting neuron phenotype.


Assuntos
Endotelina-1/fisiologia , Hormônio Liberador de Gonadotropina/metabolismo , Neurônios/metabolismo , Condutos Olfatórios/fisiologia , Linhagem Celular , Endotelina-1/farmacologia , Humanos , Radioimunoensaio , Receptor de Endotelina B/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos
11.
J Biomed Opt ; 10(2): 024004, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15910078

RESUMO

An experimental study evaluating the application of laser welding of the cornea and the subsequent healing process is presented. The welding of corneal wounds is achieved after staining the cut walls with a solution of the chromophore indocyanine green, and irradiating them with a diode laser (810 nm) operating at low power (60 to 90 mW). The result is a localized heating of the cut, inducing controlled welding of the stromal collagen. In order to optimize this technique and to study the healing process, experimental tests, simulating cataract surgery and penetrating keratoplasty, were performed on rabbits: conventional and laser-induced suturing of corneal wounds were thus compared. A follow-up study 7 to 90 days after surgery was carried out by means of objective and histological examinations, in order to optimize the welding technique and to investigate the subsequent healing process. The analyses of the laser-welded corneas evidenced a faster and more effective restoration of the architecture of the stroma. No thermal damage of the welded stroma was detected, nor were there foreign body reactions or other inflammatory processes.


Assuntos
Córnea/fisiopatologia , Córnea/cirurgia , Terapia a Laser , Cicatrização , Animais , Córnea/metabolismo , Córnea/patologia , Desenho de Equipamento , Colágenos Fibrilares/metabolismo , Imuno-Histoquímica , Terapia a Laser/instrumentação , Coelhos , Fatores de Tempo
12.
J Cataract Refract Surg ; 31(11): 2180-6, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16412936

RESUMO

PURPOSE: To determine rabbit cornea thermal tolerance and evaluate the effects of ultrasound (US) on this tissue after applying defined US heat doses. SETTING: Eye Clinic; Anatomy Histology and Forensic Medicine, University of Florence, Florence, Italy. METHODS: Hyperthermia was induced in rabbit corneas using US, simulating a phacoemulsification procedure. The US power was set at 100% in continuous mode, and temperature values were reached within 10 seconds of the onset of US treatment. Corneal surface temperatures were continuously monitored and recorded by thermographic registration. The eyes of 16 rabbits were examined: 4 controls, 8 treated at 40 degrees C for 10 seconds, 8 treated at 50 degrees C for 10 seconds, and 12 treated at 60 degrees C for 10 seconds. All 32 corneal buttons were removed and prepared for light microscopic evaluation with hematoxylin and eosin staining, trichromic staining, and zinc iodide-osmium tetroxide solution. The 12 corneas treated at 60 degrees C for 10 seconds were also processed for immunohistochemical analysis. RESULTS: Corneas at 40 degrees C for 10 seconds were grossly and histologically normal and were not different from control corneas. Corneas at 50 degrees C for 10 seconds showed initial stromal damage with collagen disorganization, mild stromal edema, and initial signs of keratocyte damage. Half of the corneas at 60 degrees C for 10 seconds were examined at time 0 and the other half after 1 week. At time 0, massive corneal damage with epithelial cell edema, collagen disorganization, severe stromal edema, intrastromal vacuole formation, plump keratocyte nuclei, and endothelial cell detachment were found, as was a severely impaired nerve plexus. At 1-week follow-up, corneas showed persistent stromal and endothelial cell edema with an increase activated keratocytes and mitotic features in the stroma and the epithelial layer. CONCLUSIONS: Rabbit corneas showed a considerable tolerance to US damage up to 50 degrees C. Higher thermal doses produced severe histological damage, even though corneas showed a considerable plasticity due to their regenerative capacity.


Assuntos
Córnea/efeitos da radiação , Doenças da Córnea/etiologia , Hipertermia Induzida/efeitos adversos , Facoemulsificação/efeitos adversos , Ultrassom/efeitos adversos , Animais , Colágeno Tipo I/metabolismo , Córnea/metabolismo , Córnea/patologia , Doenças da Córnea/diagnóstico , Doenças da Córnea/metabolismo , Desmina/metabolismo , Técnicas Imunoenzimáticas , Coelhos , Vimentina/metabolismo
13.
Acta Histochem ; 117(3): 228-34, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25769656

RESUMO

Vascular endothelial growth factor (VEGF) is a well-known mediator that signals through pathways in angiogenesis and osteogenesis. Angiogenesis and bone formation are coupled during either skeletal development or bone remodeling and repair occurring in postnatal life. In this study, we examined for the first time the expression of VEGF in human fetal mandibular and femoral bone in comparison with the respective adult tissues. Similarly to other craniofacial bones, but at variance with the axial and appendicular skeleton, during development mandible does not arise from mesoderm but neural crest cells of the neuroectoderm germ layer, and undergoes intramembranous instead of endochondral ossification. By quantitative real-time PCR technique, we could show that VEGF gene expression levels were significantly higher in fetal than in adult samples, especially in femoral tissue. Western blotting analysis confirmed higher protein expression of VEGF in the fetal femur respect to the mandible. Moreover, immunohistochemistry revealed that in both fetal tissues VEGF expression was mainly localized in pre- and osteoblasts. Differential expression of VEGF in femoral and mandibular bone tissues could be related to their different structure, function and development during organogenesis.


Assuntos
Fêmur/metabolismo , Mandíbula/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Adulto , Feto/metabolismo , Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Especificidade de Órgãos , Fator A de Crescimento do Endotélio Vascular/genética
14.
J Crohns Colitis ; 8(9): 1062-71, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24630484

RESUMO

BACKGROUND AND AIM: The adhesion molecule expression and matrix metalloproteinases (MMPs) are proposed to be major factors for intestinal injury mediated by T cells in (IBD) and are up-regulated in intestinal mucosa of IBD patients. To investigate the effect of vitamin D derivatives on adhesion molecules and MMPs in colonic biopsies of IBD patients. METHODS: Biopsies from inflamed and non-inflamed tract of terminal ileum and colon and PBMC from the same IBD patients were cultured with or without vitamin D derivatives. MMP activity and adhesion molecule levels were determined. RESULTS: 1,25(OH)2D3 and ZK 191784 significantly decrease ICAM-1 protein levels in the biopsies obtained only from the inflamed region of intestine of UC patients, while MAdCAM-1 levels decrease in the presence of 1,25(OH)2D3 in the non-inflamed region, and, in the presence of ZK, in the inflamed one. In CD patients 1,25(OH)2D3 and ZK decrease ICAM-1 and MAdCAM-1 in the biopsies obtained from the non-inflamed and inflamed regions, with the exception of ICAM-1 in the inflamed region in the presence of 1,25(OH)2D3. The expression of MMP-9, MMP-2, and MMP-3 decreases in the presence of vitamin D derivatives in UC and CD with the exception of 1,25(OH)2D3 that does not affect the levels of MMP-9 and MMP-2 in CD. Vitamin D derivatives always affect MMP-9, MMP-2 and ICAM-1 in PBMC of UC and CD patients. CONCLUSIONS: Based on the increased expression of ICAM-1, MAdCAM-1 and MMP-2,-9,-3 in IBD, our study suggests that vitamin D derivatives may be effective in the management of these diseases.


Assuntos
Calcitriol/análogos & derivados , Hidroxicolecalciferóis/uso terapêutico , Imunoglobulinas/metabolismo , Doenças Inflamatórias Intestinais/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , Mucosa Intestinal/patologia , Metaloproteinases da Matriz/metabolismo , Mucoproteínas/metabolismo , Biópsia , Western Blotting , Calcitriol/uso terapêutico , Moléculas de Adesão Celular , Células Cultivadas , Humanos , Imunoglobulinas/efeitos dos fármacos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/patologia , Molécula 1 de Adesão Intercelular/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Metaloproteinases da Matriz/efeitos dos fármacos , Mucoproteínas/efeitos dos fármacos , Vitamina D/análogos & derivados , Vitaminas
15.
Acta Histochem ; 116(5): 926-35, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24703356

RESUMO

Investigations mostly in animal models have shown a role of sialic acid in the morphology and functionality of skeletal muscle during development and adult life. Several studies in humans have been performed regarding changes in sialic acid expression in a particular pathology, hereditary inclusion body myopathy, leading to muscular weakness and atrophy, with a similar phenomenon appearing also in sarcopenia of aging. In this study the expression of monomeric and polymeric sialic acids was evaluated in human skeletal muscle during adult life. Surgical biopsies of the Quadriceps femoris muscle from men aged 18-25 years (young group; n=8) and men aged 72-78 (elderly group; n=10) were collected for analysis. Expression of sialic acids was evaluated using lectin histochemistry, associated with enzymatic and chemical treatments to characterize monomeric and polymeric sialic acids. The polysialic acid expression was also evaluated by immunohistochemistry. Various types of sialic acid in the muscle tissue, in different amounts in the study groups, were detected. Monomeric sialic acids decreased in the elderly group compared with the young group, whereas polysialic acid increased. Sialic acid acetylation was present only in the young group. These findings demonstrated that changes in the expression of sialic acids in skeletal muscle tissue may be related to morphofunctional modifications occurring during aging.


Assuntos
Regulação da Expressão Gênica , Músculo Esquelético/metabolismo , Ácido N-Acetilneuramínico/genética , Adolescente , Adulto , Idoso , Envelhecimento , Humanos , Imuno-Histoquímica , Masculino , Músculo Esquelético/anatomia & histologia , Ácido N-Acetilneuramínico/metabolismo
16.
Exp Neurol ; 257: 130-47, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24792640

RESUMO

Grafting fetal striatal cells into the brain of Huntington's disease (HD) patients has raised certain expectations in the past decade as an effective cell-based-therapy for this devastating condition. We argue that the first requirement for successful transplantation is defining the window of plasticity for the striatum during development when the progenitor cells, isolated from their environment, are able to maintain regional-specific-identity and to respond appropriately to cues. The primary cell culture from human fetal striatal primordium described here consists of a mixed population of neural stem cells, neuronal-restricted progenitors and striatal neurons. These cells express trophic factors, such as BDNF and FGF2. We show that these neurotrophins maintain cell plasticity, inducing the expression of neuronal precursor markers and cell adhesion molecules, as well as promoting neurogenesis, migration and survival. We propose that BDNF and FGF2 play an important autocrine-paracrine role during early striatum development in vivo and that their release by fetal striatal grafts may be relevant in the setting of HD cell therapy.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/farmacologia , Moléculas de Adesão Celular/metabolismo , Corpo Estriado/citologia , Fator 2 de Crescimento de Fibroblastos/farmacologia , Células-Tronco Neurais/efeitos dos fármacos , Antígenos/genética , Antígenos/metabolismo , Antígenos CD/genética , Antígenos CD/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Moléculas de Adesão Celular/genética , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Feto , Fator 2 de Crescimento de Fibroblastos/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Neuritos/efeitos dos fármacos , Neuroglia/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Antígenos O/genética , Antígenos O/metabolismo , Proteoglicanas/genética , Proteoglicanas/metabolismo
17.
PLoS One ; 8(8): e71702, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23951225

RESUMO

The claimed beneficial effects of the Mediterranean diet include prevention of several age-related dysfunctions including neurodegenerative diseases and Alzheimer-like pathology. These effects have been related to the protection against cognitive decline associated with aging and disease by a number of polyphenols found in red wine and extra virgin olive oil. The double transgenic TgCRND8 mice (overexpressing the Swedish and Indiana mutations in the human amyloid precursor protein), aged 1.5 and 4, and age-matched wild type control mice were used to examine in vivo the effects of 8 weeks dietary supplementation of oleuropein aglycone (50 mg/kg of diet), the main polyphenol found in extra virgin olive oil. We report here that dietary supplementation of oleuropein aglycone strongly improves the cognitive performance of young/middle-aged TgCRND8 mice, a model of amyloid-ß deposition, respect to age-matched littermates with un-supplemented diet. Immunofluorescence analysis of cerebral tissue in oleuropein aglycone-fed transgenic mice showed remarkably reduced ß-amyloid levels and plaque deposits, which appeared less compact and "fluffy"; moreover, microglia migration to the plaques for phagocytosis and a remarkable reduction of the astrocyte reaction were evident. Finally, oleuropein aglycone-fed mice brain displayed an astonishingly intense autophagic reaction, as shown by the increase of autophagic markers expression and of lysosomal activity. Data obtained with cultured cells confirmed the latter evidence, suggesting mTOR regulation by oleuropein aglycone. Our results support, and provide mechanistic insights into, the beneficial effects against Alzheimer-associated neurodegeneration of a polyphenol enriched in the extra virgin olive oil, a major component of the Mediterranean diet.


Assuntos
Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Polifenóis/farmacologia , Piranos/farmacologia , Animais , Autofagia/efeitos dos fármacos , Encéfalo/metabolismo , Linhagem Celular , Cognição/efeitos dos fármacos , Suplementos Nutricionais/análise , Feminino , Humanos , Glucosídeos Iridoides , Iridoides , Masculino , Transtornos da Memória/tratamento farmacológico , Transtornos da Memória/genética , Transtornos da Memória/metabolismo , Transtornos da Memória/patologia , Camundongos , Camundongos Transgênicos , Mutação , Azeite de Oliva , Óleos de Plantas/química , Polifenóis/química , Piranos/química , Serina-Treonina Quinases TOR/metabolismo
18.
J Neuroimmunol ; 236(1-2): 99-105, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21621858

RESUMO

Antibodies to myelin-associated glycoprotein (MAG) are associated with demyelinating polyneuropathy and are specific for the HNK-1 epitope. To test if anti-MAG IgM recognize HNK-1 on CNS, sera from 20 patients and 238 controls were tested on rat slices by indirect immunofluorescence (IIF). IgM from anti-MAG positive patients, but not from control sera, stained rat brain with perineuronal or neuropil pattern, depending on the CNS region. IIF titers significantly correlated with ELISA anti-MAG titers. The staining of patients' sera were inhibited by mouse anti-HNK-1 monoclonal antibody. Our results demonstrate that anti-MAG IgM recognizes HNK-1 outside the peripheral nerve myelin carriers.


Assuntos
Autoanticorpos/metabolismo , Encéfalo/imunologia , Encéfalo/metabolismo , Antígenos CD57/metabolismo , Epitopos/metabolismo , Glicoproteína Associada a Mielina/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Anticorpos Monoclonais/metabolismo , Sítios de Ligação de Anticorpos , Antígenos CD57/imunologia , Doenças Desmielinizantes/imunologia , Doenças Desmielinizantes/metabolismo , Epitopos/imunologia , Feminino , Humanos , Imunoglobulina M/metabolismo , Masculino , Pessoa de Meia-Idade , Glicoproteína Associada a Mielina/líquido cefalorraquidiano , Glicoproteína Associada a Mielina/imunologia , Ratos , Ratos Wistar
19.
Acta Histochem ; 113(3): 308-16, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-20053427

RESUMO

In this study the characterization of various types of sugar residues in normal, keratoconus and cross-linked human corneas was performed using immunohistochemical localization with lectins. Corneal samples were collected and divided into three groups: (1) normal corneas from cadavers; (2) keratoconic corneal buttons; (3) keratoconic corneal buttons treated with cross-linking. A series of lectins including: DBA, SBA, PNA, ConA, WGA, UEA I, GNA, DSA, MAA, SNA, were used in combination with chemical and enzymatic treatments. Compared with the normal corneas, N-acetyl-D-glucosamine increased in the keratoconus corneas. L-fucose increased and/or appeared in the keratoconus and the cross-linked corneas. N-acetyl-D-galactosamine was more abundant in the epithelium of keratoconus corneas, but was lacking in the keratoconus and cross-linked endothelium. D-galactose-(ß1-4)-N-acetyl-D-glucosamine was absent in the whole stroma of the keratoconus corneas and in the deep layers of the cross-linked ones. Sialic acids increased in the keratoconus corneas and decreased in the cross-linked ones. These results showed altered glycosylation in the keratoconic corneas and partially similar glycosylation in the cross-linked corneas, compared to the normal ones. This suggests a role played by sugar residues in maintaining the corneal structure. The changes could be related to structural alterations in keratoconus. The present findings contribute to our understanding of the effect of cross-linking treatment of keratoconic corneas in therapeutic attempts to re-establish the normal corneal structure.


Assuntos
Córnea/metabolismo , Ceratocone/metabolismo , Ceratocone/fisiopatologia , Lectinas/metabolismo , Carboidratos/análise , Córnea/fisiopatologia , Glicosilação , Humanos , Imuno-Histoquímica , Ligação Proteica
20.
J Neuroimmunol ; 227(1-2): 175-7, 2010 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-20696484

RESUMO

We investigated the prevalence and the clinical association of high titer of antibodies against glutamic acid decarboxylase (hGADAb) among unselected patients with inflammatory/autoimmune disorders of the nervous system. By indirect immunofluorescence examination of samples from 1435 patients, we identified 7 cases (0.48%) with hGADAb. Although stiff-person plus syndrome was the commonest clinical accompaniment, most of the patients presented with a combination of different symptoms, including psychiatric disturbances and intestinal motility disorders. Diagnosis delay and chronic evolution were common findings. In two cases persistently high values of hGADAb over the years were observed. The rarity and the phenotype heterogeneity of hGADAb clinical association should not discourage clinicians from antibody screening, at least in selected cases, as an early immunotherapy can change the otherwise chronic progression of this complex disorder spectrum.


Assuntos
Autoanticorpos/sangue , Doenças Autoimunes do Sistema Nervoso/epidemiologia , Doenças Autoimunes do Sistema Nervoso/patologia , Glutamato Descarboxilase/imunologia , Imunofenotipagem , Adulto , Idoso , Doenças Autoimunes do Sistema Nervoso/imunologia , Feminino , Seguimentos , Humanos , Incidência , Inflamação/epidemiologia , Inflamação/imunologia , Inflamação/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Rigidez Muscular Espasmódica/epidemiologia , Rigidez Muscular Espasmódica/imunologia , Rigidez Muscular Espasmódica/patologia , Adulto Jovem
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