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1.
Proc Natl Acad Sci U S A ; 119(50): e2115328119, 2022 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-36469776

RESUMO

Cancer mortality is exacerbated by late-stage diagnosis. Liquid biopsies based on genomic biomarkers can noninvasively diagnose cancers. However, validation studies have reported ~10% sensitivity to detect stage I cancer in a screening population and specific types, such as brain or genitourinary tumors, remain undetectable. We investigated urine and plasma free glycosaminoglycan profiles (GAGomes) as tumor metabolism biomarkers for multi-cancer early detection (MCED) of 14 cancer types using 2,064 samples from 1,260 cancer or healthy subjects. We observed widespread cancer-specific changes in biofluidic GAGomes recapitulated in an in vivo cancer progression model. We developed three machine learning models based on urine (Nurine = 220 cancer vs. 360 healthy) and plasma (Nplasma = 517 vs. 425) GAGomes that can detect any cancer with an area under the receiver operating characteristic curve of 0.83-0.93 with up to 62% sensitivity to stage I disease at 95% specificity. Undetected patients had a 39 to 50% lower risk of death. GAGomes predicted the putative cancer location with 89% accuracy. In a validation study on a screening-like population requiring ≥ 99% specificity, combined GAGomes predicted any cancer type with poor prognosis within 18 months with 43% sensitivity (21% in stage I; N = 121 and 49 cases). Overall, GAGomes appeared to be powerful MCED metabolic biomarkers, potentially doubling the number of stage I cancers detectable using genomic biomarkers.


Assuntos
Glicosaminoglicanos , Neoplasias , Humanos , Biomarcadores Tumorais/genética , Biópsia Líquida , Detecção Precoce de Câncer , Neoplasias/diagnóstico
2.
PLoS Comput Biol ; 19(1): e1010810, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36608159

RESUMO

The mastery of skills, such as balancing an inverted pendulum, implies a very accurate control of movements to achieve the task goals. Traditional accounts of skilled action control that focus on either routinization or perceptual control make opposite predictions about the ways we achieve mastery. The notion of routinization emphasizes the decrease of the variance of our actions, whereas the notion of perceptual control emphasizes the decrease of the variance of the states we visit, but not of the actions we execute. Here, we studied how participants managed control tasks of varying levels of difficulty, which consisted of controlling inverted pendulums of different lengths. We used information-theoretic measures to compare the predictions of alternative accounts that focus on routinization and perceptual control, respectively. Our results indicate that the successful performance of the control task strongly correlates with the decrease of state variability and the increase of action variability. As postulated by perceptual control theory, the mastery of skilled pendulum control consists in achieving stable control of goals by flexible means.


Assuntos
Movimento , Equilíbrio Postural , Humanos , Entropia , Orientação Espacial
3.
J Biol Chem ; 298(2): 101575, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35007531

RESUMO

Plasma and urine glycosaminoglycans (GAGs) are long, linear sulfated polysaccharides that have been proposed as potential noninvasive biomarkers for several diseases. However, owing to the analytical complexity associated with the measurement of GAG concentration and disaccharide composition (the so-called GAGome), a reference study of the normal healthy GAGome is currently missing. Here, we prospectively enrolled 308 healthy adults and analyzed their free GAGomes in urine and plasma using a standardized ultra-high-performance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry method together with comprehensive demographic and blood chemistry biomarker data. Of 25 blood chemistry biomarkers, we mainly observed weak correlations between the free GAGome and creatinine in urine and hemoglobin or erythrocyte counts in plasma. We found a higher free GAGome concentration - but not a more diverse composition - in males. Partitioned by gender, we also established reference intervals for all detectable free GAGome features in urine and plasma. Finally, we carried out a transference analysis in healthy individuals from two distinct geographical sites, including data from the Lifelines Cohort Study, which validated the reference intervals in urine. Our study is the first large-scale determination of normal free GAGomes reference intervals in plasma and urine and represents a critical resource for future physiology and biomarker research.


Assuntos
Glicosaminoglicanos , Adulto , Biomarcadores/sangue , Biomarcadores/urina , Cromatografia Líquida de Alta Pressão , Estudos de Coortes , Glicosaminoglicanos/sangue , Glicosaminoglicanos/química , Glicosaminoglicanos/urina , Humanos , Masculino , Espectrometria de Massas em Tandem/métodos
4.
Entropy (Basel) ; 25(9)2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37761653

RESUMO

The information bottleneck (IB) framework formalises the essential requirement for efficient information processing systems to achieve an optimal balance between the complexity of their representation and the amount of information extracted about relevant features. However, since the representation complexity affordable by real-world systems may vary in time, the processing cost of updating the representations should also be taken into account. A crucial question is thus the extent to which adaptive systems can leverage the information content of already existing IB-optimal representations for producing new ones, which target the same relevant features but at a different granularity. We investigate the information-theoretic optimal limits of this process by studying and extending, within the IB framework, the notion of successive refinement, which describes the ideal situation where no information needs to be discarded for adapting an IB-optimal representation's granularity. Thanks in particular to a new geometric characterisation, we analytically derive the successive refinability of some specific IB problems (for binary variables, for jointly Gaussian variables, and for the relevancy variable being a deterministic function of the source variable), and provide a linear-programming-based tool to numerically investigate, in the discrete case, the successive refinement of the IB. We then soften this notion into a quantification of the loss of information optimality induced by several-stage processing through an existing measure of unique information. Simple numerical experiments suggest that this quantity is typically low, though not entirely negligible. These results could have important implications for (i) the structure and efficiency of incremental learning in biological and artificial agents, (ii) the comparison of IB-optimal observation channels in statistical decision problems, and (iii) the IB theory of deep neural networks.

5.
Anal Biochem ; 655: 114848, 2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-35948059

RESUMO

Chondroitin sulfate (CS) of various molecular weight (MW), up to ∼3 kDa, were produced and tested for uronic acid carbazole assay and cetylpyridinium chloride (CPC) titration showing an evident decrease in the assays depending on the CS MW. The described results for uronic acid assay by carbazole reaction and CPC titration of CS poses the problem to know the MW values before their application and to use comparable standards to obtain reliable results. Otherwise, the related quantitative data can be affected by a great error and fake certificate of analysis.


Assuntos
Sulfatos de Condroitina , Ácidos Urônicos , Carbazóis , Cetilpiridínio , Glicosaminoglicanos , Ácido Hialurônico , Peso Molecular
6.
Pediatr Res ; 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35513714

RESUMO

BACKGROUND: The antiviral role of glycosaminoglycans in human milk (HM-GAGs) has been poorly investigated. They are highly sulfated polysaccharides, which were proposed to act as decoy receptors according to their structure. The aim of this study is to evaluate the antiviral potential and the mechanism of action of total and individual HM-GAGs against three pediatric clinically relevant viruses: respiratory syncytial virus (RSV), cytomegalovirus (HCMV), and rotavirus. METHODS: HM-GAGs were isolated from HM and a library of individual GAGs, structurally related to HM-GAGs, was prepared. The antiviral activity of HM-GAGs and the impact of thermal treatment were investigated in vitro by specific antiviral assays. RESULTS: We demonstrated that HM-GAGs are endowed with anti-HCMV and anti-RSV activity and that they act by altering virus attachment to cell. We clarified the contribution of individual HM-GAGs, showing a specific structure-related activity. We did not observe any alteration of HM-GAG antiviral activity after thermal treatment. CONCLUSIONS: We showed that HM-GAGs contribute to the overall antiviral activity of HM, likely exerting a synergic action with other HM antiviral agents. HM-GAGs can now be added to the list of endogenous factors that may reduce breast-milk-acquired HCMV symptomatic infections and protecting infants from respiratory tract infections by RSV. IMPACT: HM-GAGs have been poorly investigated for their antiviral action so far. We demonstrated that HM-GAGs are endowed with significant anti-HCMV and anti-RSV activity and that they are able to alter virus binding to the cell. The contribution of individual HM-GAGs is mainly exerted by the FMHep and is not based on a simple charge interaction between the virus and sulfate groups but involves a specific GAG structural configuration. Our results contribute to identifying the multiple factors synergically acting in mediating HM antiviral properties and to clarifying their specific mechanism of action.

7.
Entropy (Basel) ; 22(10)2020 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-33286947

RESUMO

Seeking goals carried out by agents with a level of competency requires an "understanding" of the structure of their world. While abstract formal descriptions of a world structure in terms of geometric axioms can be formulated in principle, it is not likely that this is the representation that is actually employed by biological organisms or that should be used by biologically plausible models. Instead, we operate by the assumption that biological organisms are constrained in their information processing capacities, which in the past has led to a number of insightful hypotheses and models for biologically plausible behaviour generation. Here we use this approach to study various types of spatial categorizations that emerge through such informational constraints imposed on embodied agents. We will see that geometrically-rich spatial representations emerge when agents employ a trade-off between the minimisation of the Shannon information used to describe locations within the environment and the reduction of the location error generated by the resulting approximate spatial description. In addition, agents do not always need to construct these representations from the ground up, but they can obtain them by refining less precise spatial descriptions constructed previously. Importantly, we find that these can be optimal at both steps of refinement, as guaranteed by the successive refinement principle from information theory. Finally, clusters induced by these spatial representations via the information bottleneck method are able to reflect the environment's topology without relying on an explicit geometric description of the environment's structure. Our findings suggest that the fundamental geometric notions possessed by natural agents do not need to be part of their a priori knowledge but could emerge as a byproduct of the pressure to process information parsimoniously.

8.
Eur J Pediatr ; 178(5): 739-753, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30809705

RESUMO

Mucopolysaccharidoses (MPS) are a subgroup of 11 monogenic lysosomal storage disorders due to the deficit of activity of the lysosomal hydrolases deputed to the degradation of mucopolysaccharides. Although individually rare, all together they account for at least 1:25,000 live births. In this study, we present the genetic analysis of a population of 71 MPS patients enrolled in a multicenter Italian study. We re-annotated all variants, according to the latest recommendations, and re-classified them as suggested by the American College of Medical Genetics and Genomics. Variant distribution per type was mainly represented by missense mutations. Overall, 10 patients had received no molecular diagnosis, although 6 of them had undergone either HSCT or ERT, based on clinical and enzymatic evaluations. Moreover, nine novel variants are reported.Conclusions: Our analysis underlines the need to complete the molecular diagnosis in patients previously diagnosed only on a biochemical basis, suggests a periodical re-annotation of the variants and solicits their deposition in public databases freely available to clinicians and researchers. We strongly recommend a molecular diagnosis based on the analysis of the "trio" instead of the sole proband. These recommendations will help to obtain a complete and correct diagnosis of mucopolysaccharidosis, rendering also possible genetic counseling. What is known • MPS are a group of 11 metabolic genetic disorders due to deficits of enzymes involved in the mucopolysaccharides degradation. • Molecular analysis is commonly performed to confirm enzymatic assays. What is new • Eighty-six percent of the 71 patients we collected received a molecular diagnosis; among them, 9 novel variants were reported. • We stress the importance of molecular diagnosis in biochemically diagnosed patients, encourage a periodical re-annotation of variants according to the recent nomenclature and their publication in open databases.


Assuntos
Testes Genéticos , Técnicas de Diagnóstico Molecular , Mucopolissacaridoses/diagnóstico , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Estudos de Associação Genética , Aconselhamento Genético , Marcadores Genéticos , Humanos , Lactente , Itália , Masculino , Mucopolissacaridoses/genética , Mutação de Sentido Incorreto , Adulto Jovem
9.
Molecules ; 24(8)2019 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-31013685

RESUMO

The industrial production of chondroitin sulfate (CS) uses animal tissue sources as raw material derived from different terrestrial or marine species of animals. CS possesses a heterogeneous structure and physical-chemical profile in different species and tissues, responsible for the various and more specialized functions of these macromolecules. Moreover, mixes of different animal tissues and sources are possible, producing a CS final product having varied characteristics and not well identified profile, influencing oral absorption and activity. Finally, different extraction and purification processes may introduce further modifications of the CS structural characteristics and properties and may lead to extracts having a variable grade of purity, limited biological effects, presence of contaminants causing problems of safety and reproducibility along with not surely identified origin. These aspects pose a serious problem for the final consumers of the pharmaceutical or nutraceutical products mainly related to the traceability of CS and to the declaration of the real origin of the active ingredient and its content. In this review, specific, sensitive and validated analytical quality controls such as electrophoresis, eHPLC (enzymatic HPLC) and HPSEC (high-performance size-exclusion chromatography) able to assure CS quality and origin are illustrated and discussed.


Assuntos
Sulfatos de Condroitina/análise , Sulfatos de Condroitina/química , Sulfatos de Condroitina/uso terapêutico , Suplementos Nutricionais/análise , Osteoartrite/tratamento farmacológico , Animais , Sulfatos de Condroitina/efeitos adversos , Humanos , Osteoartrite/metabolismo , Osteoartrite/patologia
10.
Electrophoresis ; 39(1): 179-189, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28857216

RESUMO

This article illustrates the basis and applications of methodologies for the analysis of simple and complex carbohydrates by means of CE. After a description of the most common and novel approaches useful for the analysis and characterization of carbohydrates, this review covers the recent advances in CE separation of monosaccharides, oligosaccharides, and polysaccharides. Various CE techniques are also illustrated for the study of carbohydrates derived from complex glyco-derivatives such as glycoproteins and glycolipids, essential for biopharmaceutical and glycoproteomics applications as well as for biomarker detection. Most glycans have no significant UV absorption, and derivatization with fluorophore groups prior to separation usually results in higher sensitivity and an improved electrophoretic profile. We also discuss the recent applications and separations by CE of derivatized simple and more complex carbohydrates with different chromophoric active tags. Overall, this review aims to give an overview of the most recent state-of-the-art techniques used in carbohydrate analysis by CE.


Assuntos
Monossacarídeos/análise , Polissacarídeos/análise , Animais , Eletroforese Capilar/métodos , Glicolipídeos/análise , Glicoproteínas/análise , Humanos , Técnicas Analíticas Microfluídicas/métodos , Oligossacarídeos/análise , Sensibilidade e Especificidade
11.
Anal Biochem ; 557: 34-41, 2018 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-30009765

RESUMO

Dried blood spot (DBS) technology is a cheap and easy method largely applied in newborn screening. Mucopolysaccharidoses (MPS) are characterized by the deficit of enzymes that degrade glycosaminoglycans (GAGs) characterized by progressive worsening of the conditions. For a possible early diagnosis of MPS, we developed a method of uronic acid (UA)-GAGs determination in DBS of 600 healthy newborns and from a small group of MPS subjects matched for age. Spotted blood UA-GAGs of the normal newborns are composed of 67.2% chondroitin sulfate (CS), 28.6% heparan sulfate (HS) and 4.4% hyaluronic acid with a CS/HS ratio of 2.35 and a total GAGs content of 0.43 µg/DBS. A chemical evaluation of CS and HS structure was performed by measuring their disaccharide composition, sulfation and the overall charge density. The DBS of four different MPS types presented an increase of total or single UA-GAGs content and/or modifications of the CS and HS disaccharide composition as well as chemical signature also related to the MPS enzymatic defect. The modifications of the UA-GAGs composition, parameters and structure of healthy newborns determined in DBS would be useful for a possible early diagnosis of various MPS types.


Assuntos
Teste em Amostras de Sangue Seco , Glicosaminoglicanos/sangue , Glicosaminoglicanos/química , Mucopolissacaridoses/sangue , Mucopolissacaridoses/diagnóstico , Configuração de Carboidratos , Humanos , Recém-Nascido
12.
BMC Med Genet ; 17: 19, 2016 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-26965916

RESUMO

BACKGROUND: Mucopolysaccharidosis type I is an autosomal recessive disorder caused by deficiency of α-L-iduronidase and characterized by a progressive course with multisystem involvement. Clinically, Mucopolysaccharidosis type I is classified into two forms: severe (Hurler syndrome), which presents in infancy and is characterized by rapid progressive neurological involvement and attenuated (Hurler/Scheie and Scheie syndromes), which presents with slower progression and absent to mild nervous system involvement. The specific treatment for attenuated Mucopolysaccharidosis type I consists of enzyme-replacement therapy with laronidase (human recombinant α-L-iduronidase, Aldurazyme). We present here the clinical and laboratory results in an 12-year-old patient affected by the attenuated form of Mucopolysaccharidosis type I treated by enzyme-replacement therapy from the age of 5 months, compared with his 17 year old affected sister, who started therapy at 5 years of age. CASE PRESENTATION: Clinical evaluation of these siblings shows that initiation of therapy prior of the onset of clinically detectable disease resulted in considerable improvement in outcome in the young sibling. After 12 years of enzyme-replacement therapy, facial appearance, linear growth rate, and liver and spleen volumes were normal; moreover, the degree of joint disease, vertebral, and cardiac valvular involvement were only minimal compared with those of his sister. CONCLUSION: This study demonstrates that early diagnosis and early initiation of enzyme-replacement therapy substantially modify the natural history of the attenuated form of Mucopolysaccharidosis type I.


Assuntos
Terapia de Reposição de Enzimas , Iduronidase/genética , Mucopolissacaridose I/genética , Mucopolissacaridose I/terapia , Adolescente , Criança , Feminino , Seguimentos , Glicosaminoglicanos/sangue , Glicosaminoglicanos/urina , Humanos , Iduronidase/deficiência , Fígado/metabolismo , Masculino , Qualidade de Vida , Baço/metabolismo
13.
Electrophoresis ; 37(11): 1514-24, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26801168

RESUMO

Free human milk oligosaccharides (HMOs) are unique due to their highly complex nature and important emerging biological and protective functions during early life such as prebiotic activity, pathogen deflection, and epithelial and immune cell modulation. Moreover, four genetically determined heterogeneous HMO secretory groups are known to be based on their structure and composition. Over the years, several analytical techniques have been applied to characterize and quantitate HMOs, including nuclear magnetic resonance spectroscopy, high-performance liquid chromatography (HPLC), high pH anion-exchange chromatography, off-line and on-line mass spectrometry (MS), and capillary electrophoresis (CE). Even if these techniques have proven to be efficient and simple, most glycans have no significant UV absorption and derivatization with fluorophore groups prior to separation usually results in higher sensitivity and an improved chromatographic/electrophoretic profile. Consequently, the analysis by HPLC/CE of derivatized milk oligosaccharides with different chromophoric active tags has been developed. However, UV or fluorescence detection does not provide specific structural information and this is a key point in particular related to the highly complex nature of the milk glycan mixtures. As a consequence, for a specific determination of complex mixtures of oligomers, analytical separation is usually required with evaluation by means of MS, which has been successfully applied to HMOs, resulting in efficient compositional analysis and profiling in various milk samples. This review aims to give an overview of the current state-of-the-art techniques used in HMO analysis.


Assuntos
Leite Humano/química , Oligossacarídeos/isolamento & purificação , Eletroforese Capilar , Feminino , Humanos , Espectrometria de Massas , Estrutura Molecular , Oligossacarídeos/análise
14.
Glycoconj J ; 33(2): 181-8, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26873820

RESUMO

In this study, the content, structure and residual percentages of glycosaminoglycans (GAGs) in the feces of seven breastfed newborns after ingesting a known amount of milk were studied. A comparison was made with five newborns fed with formula milk. Characterization of GAGs from milk and feces samples was performed according to previous methodology. Compared to the ingested GAGs present in milk, residual feces GAGs of breastfed newborns were <0.4 %, contrary to formula milk fed children, where the residues were ~4 %. As a consequence, >99 % of human milk GAGs are utilized as opposed to ~96 % of formula milk. Hyaluronic acid utilization was found to be fairly similar contrary to chondroitin sulfate/dermatan sulfate and heparan sulfate, which were found to be ~10-18 times lower in formula milk fed children. Our new results further demonstrate that the elevated content of human milk GAGs passes undigested through the entire digestive system of newborns, possibly protecting the infant from infections. In the distal gastrointestinal tract, these complex macromolecules are catabolized by a cohort of bacterial enzymes and constituent monosaccharides/oligosaccharides utilized for further metabolic purposes potentially useful for bacteria metabolism or internalized by intestinal cells. Thanks to their elevated structural heterogeneity, milk GAGs are used differently depending on their distinct primary structure. Finally, a different utilization and availability was observed for human milk GAGs compared to formula milk due to their various composition and structural heterogeneity.


Assuntos
Aleitamento Materno , Glicosaminoglicanos/metabolismo , Fórmulas Infantis , Leite Humano/metabolismo , Feminino , Humanos , Lactente , Recém-Nascido , Masculino
15.
Pediatr Res ; 79(4): 603-7, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26679156

RESUMO

BACKGROUND: Breast-fed infants have a lower incidence of acute gastroenteritis due to the presence of several anti-infective factors in human milk. The aim of this work is to study the capacity of human milk glycosaminoglycans (GAGs) to inhibit the adhesion of some common pathogenic bacteria. METHODS: GAGs were isolated from a pool of milk samples collected from different mothers during the first month of lactation. Experiments were carried out to study the ability of GAGs to inhibit the adhesion of two intestinal micro-organisms (enteropathogenic Escherichia coli serotype 0119 and Salmonella fyris) to Caco-2 and Int-407 cell lines. RESULTS: The study showed that the GAGs had an anti-adhesive effect on the two pathogenic strains studied with different degrees of inhibition. In particular, in the presence of human milk GAGs, the adhesion of S. fyris to Caco-2 cells and to Int-407 cells of both tested strains was significantly reduced. CONCLUSION: Our results demonstrated that GAGs in human milk can be one of the important defensive factors against acute diarrheal infections in breast-fed infants.


Assuntos
Aderência Bacteriana/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Glicosaminoglicanos/farmacologia , Intestinos/microbiologia , Leite Humano/metabolismo , Salmonella/efeitos dos fármacos , Células CACO-2 , Escherichia coli/fisiologia , Humanos , Técnicas In Vitro , Salmonella/fisiologia
16.
BMC Cancer ; 15: 357, 2015 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-25939870

RESUMO

BACKGROUND: ZFP36 is an mRNA binding protein that exerts anti-tumor activity in glioblastoma by triggering cell death, associated to an increase in the stability of the kinase RIP1. METHODS: We used cell death assays, size exclusion chromatography, Co-Immunoprecipitation, shRNA lentivectors and glioma neural stem cells to determine the effects of ZFP36 on the assembly of a death complex containing RIP1 and on the induction of necroptosis. RESULTS: Here we demonstrate that ZFP36 promotes the assembly of the death complex called Ripoptosome and induces RIP1-dependent death. This involves the depletion of the ubiquitine ligases cIAP2 and XIAP and leads to the association of RIP1 to caspase-8 and FADD. Moreover, we show that ZFP36 controls RIP1 levels in glioma neural stem cell lines. CONCLUSIONS: We provide a molecular mechanism for the tumor suppressor role of ZFP36, and the first evidence for Ripoptosome assembly following ZFP36 expression. These findings suggest that ZFP36 plays an important role in RIP1-dependent cell death in conditions where IAPs are depleted.


Assuntos
Proteínas Inibidoras de Apoptose/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Tristetraprolina/fisiologia , Ubiquitina-Proteína Ligases/metabolismo , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo , Apoptose , Proteína 3 com Repetições IAP de Baculovírus , Linhagem Celular Tumoral , Estabilidade Enzimática , Glioma/patologia , Células HEK293 , Humanos , Células-Tronco Neoplásicas/metabolismo , Multimerização Proteica , Proteólise
17.
J Pediatr Gastroenterol Nutr ; 60(1): 127-30, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25221936

RESUMO

OBJECTIVES: The benefits of human milk for preterm infants are mainly the result of its nutritional characteristics and the presence of biologically active compounds. Among these compounds, glycosaminoglycans (GAGs) play an emerging leading role. When mother's milk is unavailable or in short supply, pasteurised donor milk represents an important nutritional alternative. The aim of this study was to evaluate the effect of Holder pasteurisation on the concentration of different GAGs in preterm human milk. METHODS: Milk samples collected from 9 mothers having delivered preterm were divided into 2 parts. One part of each sample was immediately frozen (-80°C), whereas the other part was pasteurised with the Holder method before being frozen at -80°C. Specific analytical procedures were applied to evaluate the amount, composition, and structure of main human milk GAGs. RESULTS: No significative differences were measured between not-treated and pasteurised samples for total GAGs content, relative percentages of chondroitin sulfate and heparan sulfate, and main parameters related to galactosaminoglycans structure, even if a slight decrease of total GAGs content of ∼18% was observed in treated samples. CONCLUSIONS: Our results indicate that the Holder pasteurisation does not significatively affect the concentration of the main human milk GAGs.


Assuntos
Glicosaminoglicanos/análise , Leite Humano/química , Pasteurização , Adulto , Métodos Analíticos de Preparação de Amostras , Resinas de Troca Aniônica , Sequência de Carboidratos , Cromatografia Líquida de Alta Pressão , Feminino , Glicosaminoglicanos/química , Temperatura Alta/efeitos adversos , Humanos , Itália , Lactação , Período Pós-Parto , Nascimento Prematuro , Espectrometria de Fluorescência
18.
Cell Biochem Funct ; 33(3): 128-33, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25753066

RESUMO

Breast cyst fluid (BCF) contained in gross cists is involved with its many biomolecules in different stages of breast cystic development. Type I apocrine and type II flattened cysts are classified based on biochemical, morphological and hormonal differences, and their different patterns of growth factors and active biocompounds may require different regulation. In a previous paper, hyaluronic acid in a very low content and chondroitin sulphate/dermatan sulphate were identified and characterized in BCF. In this new study, various apocrine and flattened BCFs were analyzed for HS concentration and disaccharide pattern. Apocrine HS was found specifically constituted of N-acetyl groups contrary to flattened HS richer in N-sulphate disaccharides with an overall N-acetylated/N-sulphated ratio significantly increased in apocrine compared with flattened (13.5 vs 3.7). Related to this different structural features, the charge density significantly decreased (~-30%) in apocrine versus flattened BCFs. Finally, no significant differences were observed for HS amount (~0.9-1.3 µg ml(-1) ) between the two BCF types even if a greater content was determined for flattened samples. The specifically N-sulphated sequences in flattened BCF HS can exert biologic capacity by regulating growth factors activity. On the other hand, we cannot exclude a peculiar regulation of the activity of biomolecules in apocrine BCF by HS richer in N-acetylated disaccharides. In fact, the different patterns of growth factors and active biocompounds in the two types of cysts may require different regulation by specific sequences in the HS backbone possessing specific structural characteristics and distinctive chemical groups.


Assuntos
Líquido Cístico/metabolismo , Heparitina Sulfato/análise , Espectrometria de Massas por Ionização por Electrospray , Cromatografia Líquida de Alta Pressão , Feminino , Doença da Mama Fibrocística/metabolismo , Doença da Mama Fibrocística/patologia , Heparitina Sulfato/isolamento & purificação , Humanos , Nitrogênio/química
19.
Int J Exp Pathol ; 95(3): 181-90, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24602133

RESUMO

Proteoglycan accumulation within the arterial intima has been implicated in atherosclerosis progression in humans. Nevertheless, hypercholesterolaemia is unable to induce intimal thickening and atheroma plaque development in rats. The study was performed to analyse proteoglycans modifications in rats fed with a high-cholesterol diet to understand whether vascular wall remodelling protects against lesions. Sections obtained from rat aortas showed normal features, in intimal-to-media ratio and lipid accumulation. However, focal endothelial hyperplasia and neo-intima rearrangement were observed in high-cholesterol animals. Besides, hypercholesterolaemia induced an inflammatory microenviroment. We determined the expression of different proteoglycans from aortic cells by Western blot and observed a diminished production of decorin and biglycan in high-cholesterol animals compared with control (P < 0.01 and P < 0.05, respectively). Versican was increased in high-cholesterol animals (P < 0.05), whereas perlecan production showed no differences. No modification of the total content of glycosaminoglycans (GAGs) was found between the two experimental groups. In contrast, the chondroitin sulphate/dermatan sulphate ratio was increased in the high-cholesterol group as compared to the control (0.56 and 0.34, respectively). Structural alterations in the disaccharide composition of galactosaminoglycans were also detected by HPLC, as the ratio of 6-sulphate to 4-sulphate disaccharides was increased in high-cholesterol animals (P < 0.05). Our results suggest that attenuation of decorin and biglycan expression might be an effective strategy to inhibit the first step in atherogenesis, although specific GAG structural modification associated with the development of vascular disease took place. Results emphasize the potential application of therapies based on vascular matrix remodelling to treat atherosclerosis.


Assuntos
Aterosclerose/prevenção & controle , Proteoglicanas de Sulfatos de Condroitina/metabolismo , Dermatan Sulfato/metabolismo , Matriz Extracelular/metabolismo , Regulação da Expressão Gênica , Hipercolesterolemia/fisiopatologia , Placa Aterosclerótica/prevenção & controle , Animais , Aorta/citologia , Aorta/metabolismo , Aterosclerose/fisiopatologia , Colesterol/sangue , Proteoglicanas de Sulfatos de Condroitina/química , Dermatan Sulfato/química , Dieta Aterogênica/efeitos adversos , Modelos Animais de Doenças , Glicosaminoglicanos/química , Cabras , Humanos , Hipercolesterolemia/metabolismo , Lipídeos/sangue , Masculino , Coelhos , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
20.
Electrophoresis ; 35(6): 811-8, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24338619

RESUMO

Human milk is a unique fluid in glycobiology due to the presence of many free structurally complex oligosaccharides emerging as important dietary factors during early life and having many biological and protective functions. Methods that allow accurate profiling of oligosaccharide mixtures in this complex biological fluid with quantification of the four known genetically determined groups are welcomed. A high-voltage CE separation and detection at 254 nm of 17 neutral and acidic human milk oligosaccharide (HMO) standard along with lactose derivatized with 2-aminoacridone, using a BGE containing 20% methanol as an organic modifier and borate, able to form on-capillary anionic borate-polyol complexes, is reported. This CE approach was able to separate both neutral HMOs and acidic HMOs, with the sialic acid residue, also in the presence of lactose in high content. This method was applied to the four secretory groups individually extracted by a rapid and simple preparative step. LODs were found ranging from ∼50 to 700 fmol. We were able to measure HMO content also in the presence of excess fluorophore, or interference from proteins, peptides, salts, and other impurities normally present in this complex biological fluid. Overall, CE equipped with a UV detector is a common analytical approach and this simple CE separation offers high resolution and sensitivity for the differentiation of human milk samples related to genetic groups and days of lactation by considering that important changes in HMO content are a reflection of the lactation day.


Assuntos
Aminoacridinas/química , Eletroforese Capilar/métodos , Leite Humano/química , Oligossacarídeos/isolamento & purificação , Feminino , Humanos , Lactose/química , Lactose/isolamento & purificação , Oligossacarídeos/análise , Oligossacarídeos/química
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