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1.
EClinicalMedicine ; 39: 101049, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34430834

RESUMO

BACKGROUND: Live attenuated vaccines have been observed to have particularly beneficial effects for child survival when given in the presence of maternally transferred immunity (priming). We aimed to test this finding and furthermore explore the role of paternal priming. METHODS: In an exploratory, retrospective cohort study in 2017, parental Bacillus Calmette-Guérin (BCG) scars were assessed for infants from the Bandim Health Project (BHP) who had participated in a 2008-2013 trial of neonatal BCG vaccination. Parental scar effects on mortality were estimated from birth to 42 days, the age of the scheduled diphtheria-tetanus-pertussis (DTP) vaccination, in Cox proportional hazard models adjusted with Inverse Probability of Treatment Weighting. FINDINGS: For 66% (510/772) of main trial infants that were still registered in the BHP area, at least one parent was located. BCG scar prevalence was 77% (353/461) among mothers and 63% (137/219) among fathers. In the first six weeks of life, maternal scars were associated with a mortality reduction of 60% (95%CI, 4% to 83%) and paternal scars with 49% (-68% to 84%). The maternal scar association was most beneficial among infants that had received BCG vaccination at birth (73% (-1% to 93%)). Although priming was less evident for paternal scars, having two parents with scars reduced mortality by 89% (13% to 99%) compared with either one or none of the parents having a scar. INTERPRETATION: Parental BCG scars were associated with strongly increased early-life survival. These findings underline the importance of future studies into the subject of inherited non-specific immunity and parental priming. FUNDING: Danish National Research Foundation; European Research Council; Novo Nordisk Foundation; University of Southern Denmark.

2.
Food Funct ; 11(6): 4960-4972, 2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32500911

RESUMO

Recent research indicates that the food matrix can influence digestion kinetics and uptake of nutrients, thus affecting human health. The aim of this study was to obtain knowledge on how variations in microstructure and texture of foods represented by four dairy products; (i) cheddar cheese, (ii) a homogenized cheddar cheese, (iii) a micellar casein and cream drink or (iv) a micellar casein and cream gel, all of identical nutrient ratios of protein : fat and calcium : fat, affect the in vitro digestibility kinetics of lipids. Rheology of the four dairy structures was measured at 10 °C and 37 °C before digestion, and during the gastric phase of in vitro digestion. During digestion cheddar cheese was most resistant to enzymatic and mechanical disintegration, followed by homogenized cheese, while both the drink and gel had low resistance and dissolved in the gastric juice. Particle size, fat droplet size and microstructure were assessed by light scattering and confocal microscopy during digestion. Significantly larger fat droplets were observed during digestion of the cheddar cheese sample. The release of free fatty acids during the initial intestinal digestion showed cheddar cheese to provide a significantly lower release than homogenized cheese, whereas the drink and gel both had significantly higher free fatty acid release. The results suggest that the cheese matrix resistance to degradation and its large fat droplets were responsible for a slower fat digestion.


Assuntos
Queijo , Metabolismo dos Lipídeos , Animais , Digestão , Manipulação de Alimentos , Humanos , Reologia
3.
Nature ; 523(7560): 308-12, 2015 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-26153863

RESUMO

Surface polysaccharides are important for bacterial interactions with multicellular organisms, and some are virulence factors in pathogens. In the legume-rhizobium symbiosis, bacterial exopolysaccharides (EPS) are essential for the development of infected root nodules. We have identified a gene in Lotus japonicus, Epr3, encoding a receptor-like kinase that controls this infection. We show that epr3 mutants are defective in perception of purified EPS, and that EPR3 binds EPS directly and distinguishes compatible and incompatible EPS in bacterial competition studies. Expression of Epr3 in epidermal cells within the susceptible root zone shows that the protein is involved in bacterial entry, while rhizobial and plant mutant studies suggest that Epr3 regulates bacterial passage through the plant's epidermal cell layer. Finally, we show that Epr3 expression is inducible and dependent on host perception of bacterial nodulation (Nod) factors. Plant-bacterial compatibility and bacterial access to legume roots is thus regulated by a two-stage mechanism involving sequential receptor-mediated recognition of Nod factor and EPS signals.


Assuntos
Lipopolissacarídeos/metabolismo , Lotus/metabolismo , Lotus/microbiologia , Proteínas de Plantas/metabolismo , Receptores de Superfície Celular/metabolismo , Rhizobium/metabolismo , Simbiose , Sequência de Aminoácidos , Sequência de Carboidratos , Lipopolissacarídeos/química , Lotus/genética , Dados de Sequência Molecular , Mutação/genética , Fenótipo , Epiderme Vegetal/metabolismo , Epiderme Vegetal/microbiologia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Nodulação , Proteínas Quinases/química , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Estrutura Terciária de Proteína , Receptores de Superfície Celular/química , Receptores de Superfície Celular/genética , Nódulos Radiculares de Plantas/metabolismo , Nódulos Radiculares de Plantas/microbiologia , Transdução de Sinais , Especificidade da Espécie , Supressão Genética/genética
4.
Allergy ; 68(9): 1168-76, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23991838

RESUMO

BACKGROUND: Recent evidence suggests that immunogenic interventions such as vaccines and micronutrients may affect atopic sensitization and atopic disease. We aimed to determine whether neonatal BCG vaccination, vitamin A supplementation and other vaccinations affect atopy in childhood. METHODS: In Guinea-Bissau, low-birthweight infants were randomized to early (intervention) or delayed (usual policy) BCG. A subgroup was also randomly assigned vitamin A supplementation or placebo in a two-by-two factorial design. Participants were followed up at age 3-9 years. The main outcome was atopy defined as skin prick test reaction ≥3 mm. Secondary outcomes were symptoms of eczema, asthma and food allergy. RESULTS: Two hundred eighty-one children had valid skin prick tests performed, and 14% (39/281) were atopic. There was no significant difference in atopy between the early and delayed BCG groups (OR, 0.71; 95% CI, 0.34-1.47). Atopy was significantly reduced in children who had responded to BCG with a scar (OR, 0.42; 0.19-0.94). Vitamin A supplementation was associated with increased atopy (OR, 2.88; 1.26-6.58), especially in those who received simultaneous BCG (5.99; 1.99-18.1, P = 0.09 for interaction between vitamin A supplementation and BCG). Early vs delayed BCG was not associated with symptoms of atopic disease, but vitamin A supplementation increased odds of wheeze within the past 12 months (OR, 2.45; 1.20-4.96). CONCLUSIONS: There were no statistically significant effects of early vs delayed BCG on atopy or symptoms of atopic disease. Having a BCG scar was associated with reduced atopy, whereas neonatal vitamin A supplementation was associated with increased atopy. STUDY REGISTRATION: Clinicaltrials.gov NCT 01420705.


Assuntos
Vacina BCG/imunologia , Suplementos Nutricionais , Hipersensibilidade Imediata/etiologia , Vitamina A/administração & dosagem , Vacina BCG/administração & dosagem , Vacina contra Difteria, Tétano e Coqueluche/administração & dosagem , Vacina contra Difteria, Tétano e Coqueluche/imunologia , Feminino , Seguimentos , Humanos , Hipersensibilidade Imediata/epidemiologia , Recém-Nascido , Masculino , Vacina contra Sarampo/administração & dosagem , Vacina contra Sarampo/imunologia , Prevalência , Fatores de Risco
5.
Cell Mol Life Sci ; 59(5): 859-69, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12088285

RESUMO

An understanding of very complex natural systems can often only be achieved through detailed studies of systems with a reduced complexity. Thus, de novo design of proteins allows the study of fundamental forces determining protein folding and stability, as well as protein-protein interactions, by analyses of protein models of structural motifs. In addition, de novo design may lead to new biomimetic molecules with novel properties. In a synthetic approach to achieve structural economy, rigid templates, sometimes called topological scaffolds, have been used to connect secondary-structure elements, most notably alpha-helices. By positioning the helices on the template, the unfavorable entropy of protein folding is reduced. In a novel class of chimeric molecules called carboproteins, carbohydrates are used as templates for de novo design of protein models. Recently, a strategy relying on chemoselective ligation of C-terminal peptide aldehydes to tetra-aminooxy functionalized monosaccharides has provided 7-kDa 4-alpha-helix bundle carboproteins.


Assuntos
Carboidratos/química , Estrutura Terciária de Proteína , Proteínas/química , Metabolismo dos Carboidratos , Modelos Moleculares , Estrutura Molecular , Peptídeos/química , Peptídeos/metabolismo , Dobramento de Proteína , Estrutura Secundária de Proteína , Proteínas/metabolismo , Moldes Genéticos
6.
J Org Chem ; 66(19): 6268-75, 2001 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-11559173

RESUMO

Efficient, stereoselective glycosylation methods are required for the synthesis of complex oligosaccharides as tools in glycobiology. All glycosylation methods, which have found wide acceptance, rely on Lewis acid activation of glycosyl donors prior to glycosylation. Here, we present a new and efficient method for glycosylation under neutral or mildly basic conditions. Glycosides of methyl 2-hydroxy-3,5-dinitrobenzoate (DISAL) and its para regioisomer, methyl 4-hydroxy-3,5-dinitrobenzoate, were prepared by nucleophilic aromatic substitution. In a first demonstration of their potential as glycosyl donors, stereospecific glycosylation of methanol was achieved. In the glycosylation of more hindered alcohols, the beta-donor proved more reactive, and alpha-glucosides were predominantly formed. Glycosylation of protected monosaccharides, with free 6-OH or 3-OH, proceeded smoothly in 1-methyl-2-pyrrolidinone (NMP) at 40-60 degrees C in the absence of Lewis acids and bases in good to excellent yields. Glycosylation of 3-OH gave the alpha-linked disaccharide only.


Assuntos
Glicosídeos/química , Nitrobenzoatos/química , Oligossacarídeos/síntese química , Glicosilação
7.
Bioorg Med Chem Lett ; 11(5): 697-700, 2001 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-11266172

RESUMO

We have recently introduced the concept of monosaccharides as templates for de novo design of protein models and described the synthesis of a model 'carbopeptide'. Here, we report the synthesis of a 64 amino acid (AA) 'carboprotein' by chemoselective ligation of a C-terminal hexadecapeptide aldehyde to a tetra-aminooxy functionalized methyl alpha-D-galactopyranoside (D-Galp) template. Biophysical characterizations by CD spectroscopy and NMR amide H-D exchange experiments indicated that the four-stranded carboprotein forms a 4-alpha-helix bundle structure.


Assuntos
Galactose/química , Peptídeos/química , Conformação Proteica , Dicroísmo Circular , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Peptídeos/síntese química , Moldes Genéticos
8.
Org Lett ; 3(5): 687-90, 2001 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-11259037

RESUMO

[structure: see text]. A new method for intramolecular glycosylation, in which the donor and acceptor were linked via a 3,5-dinitrosalicylic acid derivative, was developed. Simply dissolving the tethered glycoside in CH3NO2 and warming to 40-60 degrees C led to formation of 1,4-linked disaccharides under neutral, hence, exceptionally mild, conditions.


Assuntos
Dissacarídeos/síntese química , Glicosilação , Hidrólise
9.
J Pept Res ; 56(1): 3-11, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10917452

RESUMO

De novo design of proteins has evolved into a powerful approach for studying the factors governing protein folding and stability. Among the families of structures frequently studied is the 'four-helix bundle' in which four alpha-helical peptide strands, linked by loops, form a hydrophobic core. Assembly of protein models on a template has been suggested as a way to reduce the entropy of folding. Here we describe the potential use of a carbohydrate as such a template. The monosaccharide D-galactose was per-O-acylated with (Nbeta-Fmoc-betaAla)2O to give a penta-substituted derivative, which was converted to the corresponding glycosyl bromide and used for the glycosylation of 4-hydroxymethylbenzoic acid pentafluorophenyl ester (HMBA-OPfp). The beta-glycosidic carbohydrate template (Nbeta-Fmoc-3Ala)4-beta-D-Galp-(1-O)-MBA-OPfp thus obtained was coupled to a PAL-PEG-PS resin and simultaneously extended at the four arms to yield, after cleavage from the solid support, a carbopeptide with four identical peptide strands. Extension of this concept to, for example, synthesis of novel multiple antigenic peptides (MAPs) and synthesis of carbohydrate clusters can be easily envisioned. The ability to efficiently synthesize such structures sets the stage for further studies to test whether the carbohydrate templates do indeed nucleate folding.


Assuntos
Carboidratos/síntese química , Peptídeos/síntese química , Metabolismo dos Carboidratos , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Desenho de Fármacos , Fluorenos/química , Glicosilação , Espectroscopia de Ressonância Magnética , Modelos Químicos , Estrutura Molecular , Elongação Traducional da Cadeia Peptídica , Peptídeos/metabolismo , Dobramento de Proteína , Moldes Genéticos
10.
J Pept Sci ; 6(6): 290-9, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10912909

RESUMO

Multifunctional, topological template molecules such as linear and cyclic peptides have been used for the attachment of peptide strands to form novel protein models of, for example, 4-alpha-helix bundles. The concept of carbohydrates as templates for de novo design of potential protein models has been previously described and these novel chimeric compounds were termed carbopeptides. Here, a second generation strategy in which carbopeptides are synthesized by chemoselective ligation of a peptide aldehyde to an aminooxy-functionalized alpha-D-galactopyranoside is described. This template was prepared by per-O-acylation of methyl alpha-D-galactopyranoside with N,N-Boc2-aminooxyacetic acid to form a tetra-functionalized template, followed by treatment with TFA-CH2Cl2 to release the aminooxy functionality. The peptide aldehydes Fmoc-Ser-Gly-Gly-H and H-Ala-Leu-Ala-Lys-Leu-Gly-Gly-H were synthesized by a BAL strategy. Four identical copies of peptide aldehyde were smoothly attached to the template by chemoselective ligation to form a 2.1 and a 2.9 kDa carbopeptide, respectively.


Assuntos
Aldeídos/química , Carbono/química , Galactose/química , Peptídeos/química , Peptídeos/metabolismo , Aldeídos/metabolismo , Cromatografia Líquida de Alta Pressão , Galactose/síntese química , Espectroscopia de Ressonância Magnética , Modelos Químicos , Oximas/síntese química , Oximas/química , Biossíntese Peptídica , Peptídeos/síntese química
11.
J Comb Chem ; 2(2): 143-50, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10757094

RESUMO

The solid-phase synthesis of a small library of mimetics of the cyclic depsipeptide hapalosin is described. 3-Amino-4-hydroxy-5-nitrobenzoic acid was anchored through the anilino moiety to a backbone amide linker (BAL) handle support. Using chemoselective reactions and without the need for protecting group manipulations, the benzoic acid group was first amidated, then the aniline nitrogen was acylated, and finally the nitro group was reduced to an amine and acylated or reductively alkylated, to generate a 12-member library.


Assuntos
Depsipeptídeos , Lactamas/síntese química , Lactonas/síntese química , Alquilação , Compostos de Anilina/química , Química Orgânica , Indicadores e Reagentes , Modelos Químicos , Fenômenos de Química Orgânica , Biblioteca de Peptídeos
12.
J Pept Res ; 55(1): 81-91, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10667864

RESUMO

The glycopeptide hormone catfish somatostatin (somatostatin-22) has the amino acid sequence H-Asp-Asn-Thr-Val-Thr-Ser-Lys-Pro-Leu-Asn-Cys-Met-Asn-Tyr-Phe-Trp-Lys-Se r-Arg-Thr-Ala-Cys-OH; it includes a cyclic disulfide connecting the two Cys residues, and the major naturally occurring glycoform contains D-GalNAc and D-Gal O-glycosidically linked to Thr5. The linear sequence was assembled smoothly starting with an Fmoc-Cys(Trt)-PAC-PEG-PS support, using stepwise Fmoc solid-phase chemistry. In addition to the nonglycosylated peptide, two glycosylated forms of somatostatin-22 were accessed by incorporating as building blocks, respectively, Nalpha-Fmoc-Thr(Ac3-alpha-D-GalNAc)-OH and Nalpha-Fmoc-Thr(Ac4-beta-D-Gal-(1-->3)-Ac2-alpha-D-GalNAc)-O H. Acidolytic deprotection/cleavage of these peptidyl-resins with trifluoroacetic acid/scavenger cocktails gave the corresponding acetyl-protected glycopeptides with free sulfhydryl functions. Deacetylation, by methanolysis in the presence of catalytic sodium methoxide, was followed by mild oxidation at pH 7, mediated by Nalpha-dithiasuccinoyl (Dts)-glycine, to provide the desired monomeric cyclic disulfides. The purified peptides were tested for binding affinities to a panel of cloned human somatostatin receptor subtypes; in several cases, presence of the disaccharide moiety resulted in 2-fold tighter binding.


Assuntos
Peixes-Gato , Receptores de Somatostatina/metabolismo , Somatostatina/síntese química , Somatostatina/metabolismo , Sequência de Aminoácidos , Animais , Bioquímica/métodos , Dissulfetos/química , Glicoproteínas/síntese química , Glicoproteínas/metabolismo , Glicosilação , Humanos , Dados de Sequência Molecular
13.
Int J Pept Protein Res ; 43(6): 529-36, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7928083

RESUMO

In order to investigate the possible extent of beta-elimination occurring in Fmoc-based continuous-flow solid-phase glycopeptide synthesis, the influence of the pKb of the base used for N alpha-deprotection has been studied. A glycosylated pentapeptide was synthesized using 50% morpholine, 10% piperidine or 2% DBU, respectively, in DMF for deprotection. The dehydropentapeptide N alpha-Ac-Thr-Thr-delta Aba-Val-Thr-NH2, which would be formed in the case of beta-elimination, was prepared independently and used as a control in HPLC analysis; however, this product was not formed under any of the deprotection conditions applied. Furthermore, a 23 amino acid long glycopeptide from human intestinal mucin was prepared using 2% DBU as a base for Fmoc cleavage, and similarly no beta-elimination was observed. The glycopeptide products were subjected to a prolonged treatment with sodium hydroxide in methanol/water without significant formation of byproducts, and the pure glycopeptides were isolated and characterized by 1H-NMR spectroscopy.


Assuntos
Aminoácidos/química , Fluorenos/química , Glicopeptídeos/síntese química , Polissacarídeos/química , Sequência de Aminoácidos , Compostos Bicíclicos com Pontes , Dados de Sequência Molecular , Mucinas/síntese química
14.
Clin Otolaryngol Allied Sci ; 4(5): 339-42, 1979 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-487632

RESUMO

In 63 patients with otosclerosis confirmed by operation, the bone mineral content was determined by photon absorptiometry. The bone mineral content and bone mineral concentration were found to be normal, which lends support to the assumption that otosclerosis is a localized disease and not a manifestation of a generalized disorder of the skeletal system.


Assuntos
Osso e Ossos/análise , Minerais/análise , Otosclerose/metabolismo , Absorção , Adulto , Idoso , Fosfatase Alcalina/sangue , Cálcio/sangue , Partículas Elementares , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fósforo/sangue , Fatores de Tempo
15.
Clin Otolaryngol Allied Sci ; 4(4): 259-66, 1979 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-476990

RESUMO

In a retrospective study of 144 fertile women subjected to operation for otosclerosis by the method of Shea or House, we found a fall in the hearing threshold in the operated ear which seemed to be a little greater in the patients who became pregnant after the operation than in those who did not. However, the hearing loss was significantly greater in the non-operated ear in the patients who became pregnant after the operation than in those who did not.


Assuntos
Limiar Auditivo/fisiologia , Otosclerose/complicações , Complicações na Gravidez/fisiopatologia , Cirurgia do Estribo/métodos , Adolescente , Adulto , Feminino , Perda Auditiva/etiologia , Humanos , Otosclerose/fisiopatologia , Otosclerose/cirurgia , Gravidez
16.
J Laryngol Otol ; 93(7): 697-702, 1979 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-469399

RESUMO

In 22 patients with osteogenesis imperfecta and in 63 patients with otosclerosis the bone mineral content in peripheral bones was determined by photon absorptiometry. The bone mineral content proved significantly reduced in patients with osteogenesis imperfecta as compared with normals and with patients with otosclerosis. In the latter patients the bone mineral content was normal. These findings support the assumption that stapedial fixation in otosclerosis and in osteogenesis imperfecta is of different aetiology.


Assuntos
Osso e Ossos/análise , Minerais/análise , Osteogênese Imperfeita/metabolismo , Otosclerose/metabolismo , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
17.
J Laryngol Otol ; 90(11): 1007-13, 1976 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1003025

RESUMO

Esthesioneuroblastomas are malignant tumours, usually of slow, invasive growth and low metastatic rate. Skeletal destruction must be assumed to be common, but is often demonstrable only by tomographic sections. Clinically these tumours do not differ from others of the same site, so that the diagnosis has to be based upon the histological appearances. In the light microscope the presence of neurofibrils is considered a specific differential diagnostic factor against other small-cell malignant tumours in this region. There seems to be no basis for a morphological classification into previously described sub-groups, neither according to histogenetic, light, nor ultra-microscopic findings. The general degree of differentiation and the number of mitoses appear to be the main factors of prognostic significance. Combined irradiation and surgical excision is considered the best treatment.


Assuntos
Tumores Neuroectodérmicos Primitivos Periféricos , Neoplasias Nasais , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tumores Neuroectodérmicos Primitivos Periféricos/diagnóstico , Tumores Neuroectodérmicos Primitivos Periféricos/epidemiologia , Tumores Neuroectodérmicos Primitivos Periféricos/terapia , Neoplasias Nasais/diagnóstico , Neoplasias Nasais/epidemiologia , Neoplasias Nasais/terapia
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