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1.
Biofactors ; 50(1): 161-180, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37597249

RESUMO

Recent reports indicated that the phytochemical curcumin possesses iron-chelating activity. Here, by employing the fruit fly Drosophila melanogaster, we conducted feeding studies supplementing curcumin or, as a control, the iron chelator bathophenanthroline (BPA). First, the absorption and further metabolization of dietary curcuminoids were proved by metabolomics analyses. Next, we found that 0.2% dietary curcumin, similar to BPA, lowered the iron but also the cobalt content, and to a lesser extent affected the manganese and zinc status. Supplementation during larval stages was required and sufficient for both compounds to elicit these alterations in adult animals. However, curcumin-induced retarded larval development was not attributable to the changed trace metal status. In addition, a reduction in the iron content of up to 70% by curcumin or BPA supplementation did not reduce heme-dependent catalase activity and tolerance toward H2 O2 in D. melanogaster. Moreover, polyamines were not influenced by curcumin treatment and decreased iron levels. This was confirmed for selected organs from 0.2% curcumin-treated mice, except for the spleen. Here, elevated spermidine level and concomitant upregulation of genes involved in polyamine production were associated with a putatively anemia-derived increased spleen mass. Our data underline that the metal-chelating property of curcumin needs to be considered in feeding studies.


Assuntos
Curcumina , Drosophila melanogaster , Camundongos , Animais , Drosophila melanogaster/genética , Curcumina/farmacologia , Cobalto , Poliaminas , Ferro , Estresse Oxidativo , Quelantes , Antioxidantes , Suplementos Nutricionais
2.
Food Chem ; 428: 136698, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37413838

RESUMO

Ultraviolet (UV) B irradiation induces protein modification, especially the conformational rearrangement of proteins, and is therefore promising as a non-thermal and non-chemical functionalization technique. Nevertheless, UVB irradiation introduces radicals and oxidizes side chains resulting in the loss of food quality. Thus, assessing the UVB irradiation-based functionalization of ß-lactoglobulin (BLG) versus its oxidative degradation is of interest. UVB irradiation of up to 8 h was successfully applied to loosen the rigid folding of BLG and increase its flexibility. Thereby, the cysteine at position 121 and hydrophobic regions became surface-exposed as indicated by the increase in accessible thiol groups and increased surface hydrophobicity. Furthermore, we demonstrated the cleavage of the "outer" disulfide bond C66-C160 by LC-MS/MS after tryptic digestion of BLG. The 2-h-irradiated BLG showed adequate conformational rearrangement for protein functionalization while being minimally oxidized.


Assuntos
Lactoglobulinas , Espectrometria de Massas em Tandem , Lactoglobulinas/química , Cromatografia Líquida , Raios Ultravioleta , Estresse Oxidativo
3.
Food Chem ; 415: 135357, 2023 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-36842373

RESUMO

Lipid oxidation induced protein scission was investigated in oleogel using beta-lactoglobulin (whey protein isolate) as gelator. Extracted cleaved peptides were measured using high resolution mass spectrometry (FT-ICR-MS), which was provided by an automatically generated annotation list approach to identify relevant masses and sum formula using the isotopic pattern. The identified oxidized peptides were then further evaluated using partial least squares regression to relevant lipid hydroperoxide formation data, which provide the significance and importance of the peptides toward lipid induced scission. Thereby, the most important peptides are located at the surface of the protein in random coil segments and especially at the ends of the protein sequence. The most important amino acids were cysteine and aliphatic amino acids, which undergo scission mostly by the α-amidation pathway. The findings compare well with studies investigating depletion of amino acids initiated by lipid oxidation in systems containing bovine albumin or gamma-globulin.


Assuntos
Aminoácidos , Peptídeos , Animais , Bovinos , Oxirredução , Peptídeos/química , Aminoácidos/química , Soroalbumina Bovina , Lipídeos
4.
Nutrients ; 14(9)2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35565905

RESUMO

Vitamins and omega-3 fatty acids (Ω3FA) modulate periodontitis-associated inflammatory processes. The aim of the current investigation was to evaluate associations of oral nutrient intake and corresponding serum metabolites with clinical severity of human periodontitis. Within the Food Chain Plus cohort, 373 periodontitis patients­245 without (POL) and 128 with tooth loss (PWL)­were matched to 373 controls based on sex, smoking habit, age and body mass index in a nested case-control design. The amount of oral intake of vitamins and Ω3FAs was assessed from nutritional data using a Food Frequency Questionnaire. Oral intake and circulatory bioavailability of vitamins and Ω3FA serum metabolomics were compared, using ultra-high-resolution mass spectrometry. Periodontitis patients exhibited a significantly higher oral intake of vitamin C and Ω3FA Docosapentaenoic acid (p < 0.05) compared to controls. Nutritional intake of vitamin C was higher in PWL, while the intake of Docosapentaenoic acid was increased in POL (p < 0.05) compared to controls. In accordance, serum levels of Docosapentaenoic acid were also increased in POL (p < 0.01) compared to controls. Vitamin C and the Ω3FA Docosapentaenoic acid might play a role in the pathophysiology of human periodontitis. Further studies on individualized nutritional intake and periodontitis progression and therapy are necessary.


Assuntos
Ácidos Graxos Ômega-3 , Periodontite , Ácido Ascórbico , Estudos de Casos e Controles , Humanos , Periodontite/metabolismo , Vitaminas
5.
Gut Microbes ; 14(1): 2057778, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35435797

RESUMO

Recent rodent microbiome experiments suggest that besides Akkermansia, Parasutterella sp. are important in type 2 diabetes and obesity development. In the present translational human study, we aimed to characterize Parasutterella in our European cross-sectional FoCus cohort (n = 1,544) followed by validation of the major results in an independent Canadian cohort (n = 438). In addition, we examined Parasutterella abundance in response to a weight loss intervention (n = 55). Parasutterella was positively associated with BMI and type 2 diabetes independently of the reduced microbiome α/ß diversity and low-grade inflammation commonly found in obesity. Nutritional analysis revealed a positive association with the dietary intake of carbohydrates but not with fat or protein consumption. Out of 126 serum metabolites differentially detectable by untargeted HPLC-based MS-metabolomics, L-cysteine showed the strongest reduction in subjects with high Parasutterella abundance. This is of interest, since Parasutterella is a known high L-cysteine consumer and L-cysteine is known to improve blood glucose levels in rodents. Furthermore, metabolic network enrichment analysis identified an association of high Parasutterella abundance with the activation of the human fatty acid biosynthesis pathway suggesting a mechanism for body weight gain. This is supported by a significant reduction of the Parasutterella abundance during our weight loss intervention. Together, these data indicate a role for Parasutterella in human type 2 diabetes and obesity, whereby the link to L-cysteine might be relevant in type 2 diabetes development and the link to the fatty acid biosynthesis pathway for body weight gain in response to a carbohydrate-rich diet in obesity development.


Assuntos
Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Canadá , Estudos Transversais , Cisteína , Carboidratos da Dieta , Ácidos Graxos , Humanos , Obesidade , Redução de Peso
6.
Dtsch Med Wochenschr ; 147(1-02): 46-52, 2022 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-34963174

RESUMO

Ultra-processed food is part of a modern lifestyle and accounts for about 46 % of daily energy intake in Germany. Cross-sectional and cohort studies indicate associations between consumption of ultra-processed food and a range of non-communicable diseases (obesity, diabetes, cancer, cardiovascular disease, and depression). As underlying mechanisms, a high energy density, altered food matrix, an unbalanced nutritional composition, high glycemic index, adverse additives, processing- and packaging contaminants are discussed. In order to understand the role of these potential mechanisms and to provide a scientifically based and risk-associated definition of ultra-processed food it is important to conduct appropriate intervention studies and to improve dietary assessment of processed food in prospective cohort studies.


Assuntos
Dieta/efeitos adversos , Fast Foods , Obesidade , Diabetes Mellitus , Alemanha , Humanos , Neoplasias
7.
Childs Nerv Syst ; 37(10): 3199-3207, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34529089

RESUMO

INTRODUCTION: Brachycephaly and anterior and posterior plagiocephaly appear as an isolated entity or manifest in syndromic conditions. In severe cases, possible treatment options currently comprise either cranioplasty or osteogenetic distraction. The aim of this paper is to retrospectively review the perioperative course of a series of children treated by posterior meander expansion technique at our institution with focus on the course of postoperative intracranial volume and eventual tonsillar descent evolution. METHODS: Forty-two children received a posterior cranial vault remodeling by means of a posterior meander technique during a 7-year period. Hospital records were reviewed, and pre- and postoperative MRIs were analyzed for intracranial volume, cephalic and asymmetry index, and tonsillar position over time. RESULTS: Median age at surgery was 11.5 months (range 17 days-10 years). Nineteen children had a symmetrical cranial deformity, twenty-three an asymmetrical synostosis. Half of the cohort showed a syndromic condition. Transfusions were administered in the majority (92.2%) of the cases. A significant postoperative increase of intracranial volume was present from 1188.9 ± 370.4 cm3 to 1324.8 ± 352.9 cm3 (p < 0.001). The asymmetry index showed a significant improvement postoperatively: 0.86 ± 0.06 versus 0.91 ± 0.05 (p < 0.001), while the cephalic index showed a non-statistical change (0.91 ± 0.11 versus 0.88 ± 0.08). Tonsillar herniation, bilateral or homolateral, showed no significant changes at early control, while a nonsignificant amelioration of tonsillar descent was seen among children older than 12 months at late imaging follow-up. CONCLUSION: Among the osteoplastic techniques, the posterior meander technique offers several advantages, such as early mobilization of the child, less bony defects, absence of implants, and a small complication rate. However, further comparative studies among different surgical techniques are needed.


Assuntos
Craniossinostoses , Osteogênese por Distração , Plagiocefalia , Criança , Craniossinostoses/diagnóstico por imagem , Craniossinostoses/cirurgia , Humanos , Lactente , Estudos Retrospectivos , Crânio/diagnóstico por imagem , Crânio/cirurgia , Resultado do Tratamento
8.
Clin Nutr ; 40(2): 600-607, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32600859

RESUMO

BACKGROUND: FGF-21 is described as a powerful metabolic regulator with beneficial effects including glucose-lowering and improvement of insulin sensitivity without hypoglycaemia. On the other hand, FGF-21 is activated when muscle and other tissues are stressed by external effects or internal cellular pathogens that lead to shortcomings in metabolic balance. Previous results suggested that FGF-21 could be a promising target to develop future metabolic therapeutics. PURPOSE: The present study was performed to gain deeper insight into the regulation of FGF-21 by protein metabolism in obese human subjects. METHODS: FGF-21 serum concentrations were measured in a cohort of n = 246 obese humans ± type 2 diabetes mellitus (T2DM) (median age 53.0 [46.0; 60.0] years and BMI 40.43 [35.11; 47.24] kg/m2) and related to the nutritional protein intake. In addition, the effect of a novel oligopeptide purified from a ß-casein hydrolysate on FGF-21 was examined in vitro in liver cells and in vivo in a human intervention study with the main focus on metabolic inflammation including 40 mainly obese subjects (mean age 41.08 ± 9.76 years, mean BMI 38.29 ± 9.4 kg/m2) in a randomized 20 weeks double-blind cross-over design. MAIN FINDINGS: In the cohort analysis, FGF-21 serum concentrations were significant lower with higher protein intake in obese subjects without T2DM but not in obese subjects with T2DM. Furthermore, relative methionine intake was inversely related to FGF-21. While global protein intake in obesity was inversely associated with FGF-21, incubation of HepG2 cells with a ß-casein oligopeptide increased FGF-21 expression in vitro. This stimulatory effect was also present in vivo, since in the clinical intervention study treatment of obese subjects with the ß-casein oligopeptide for 8 weeks significantly increased FGF-21 serum levels from W0 = 23.86 pg/mL to W8 = 30.54 pg/mL (p < 0.001), while no increase was found for placebo. CONCLUSION: While the total nutritional protein intake is inversely associated with FGF-21 serum levels, a purified and well characterised oligopeptide is able to induce FGF-21 serum levels in humans. These findings suggest a differential role of various components of protein metabolism on FGF-21, rather than this factor being solely a sensor of total nutritional protein intake.


Assuntos
Proteínas Alimentares/sangue , Ingestão de Alimentos/fisiologia , Fatores de Crescimento de Fibroblastos/sangue , Obesidade/sangue , Oligopeptídeos/administração & dosagem , Caseínas/química , Estudos Cross-Over , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Método Duplo-Cego , Feminino , Células Hep G2 , Humanos , Técnicas In Vitro , Resistência à Insulina , Masculino , Pessoa de Meia-Idade , Obesidade/complicações
9.
J Agric Food Chem ; 68(39): 10865-10874, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-32865997

RESUMO

High and low levels of lipid-induced protein oxidation (tuned by the addition of 0%-8.4% water) were investigated in oleogels, using excitation-emission matrix (EEM) fluorescence spectroscopy, coupled with a partial least-squares (PLS) regression and lipid hydroperoxide data. In high-level oxidation models, the intrinsic tryptophan fluorescence decreased and the emission maxima increased from 352.5 to 356.0 nm indicating the presence of protein modifications, which was further supported by size-exclusion chromatography. PLS recognized 3 latent components, with several excitation-emission points of interest. These apparent compounds include a region associated with radical mediated protein modifications (approximately 325 and 410 nm), lipid oxidation product adducts (approximately 350 nm and 420-425 nm), and malondialdehyde adducts (approximately 375 and 425 nm). The separate evaluation of these apparent compounds, at a 420 nm emission, indicated that lipid oxidation promotes protein lipid adduct fluorescence at high water levels, rather than radical mediated protein fluorescence.


Assuntos
Lipídeos/química , Proteínas/química , Fluorescência , Compostos Orgânicos/química , Oxirredução , Espectrometria de Fluorescência , Água/química
10.
Food Chem ; 328: 127123, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-32480261

RESUMO

Protein- and lipid oxidation were investigated in whey protein based oleogels with varying water addition. Lipid oxidation was low (~30 mmol O2/kg lipid hydroperoxides after 6 weeks) in gels with < 0.23% water and a high (>1,000 mmol O2/kg lipid hydroperoxides after 4 weeks) in gels with > 2.4% water addition. In systems with > 2.4% water addition fluorescence (excitation 325 nm / emission 410 nm) as indicator of tyrosine oxidation and carbonyl content significantly increased and remained at low levels in oleogels with < 0.23% water addition. Primary amines as indicator for protein backbone breakage increased in early stages of oxidation in high water oleogels and decreased after 28 days. Degradation has been suggested to occur through interactions with reactive secondary lipid oxidation products and was confirmed by spiking experiments using respective compounds. The results suggest that secondary lipid oxidation markers are masked dependent on water addition in the presence of proteins.


Assuntos
Lipídeos/química , Água/química , Proteínas do Soro do Leite/química , Aminas/química , Géis/química , Compostos Orgânicos/química , Oxirredução
11.
Zentralbl Chir ; 145(1): 75-81, 2020 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-31167248

RESUMO

Treatment of major congenital diaphragmatic hernia (CDH) is a challenging task in paediatric surgery. Gore-Tex® is now commonly used to treat CDH, but it carries the risk of recurrences, infections and other complications. The aim of our study was to analyse to what extent Lyoplant® - an acellular, avascular biocompatible collagen mesh - is suitable for CDH in the rat model. METHODS: A median laparotomy was performed in young Wistar Furth rats with a body weight of 155 - 205 g. A defect was created by excising a 1.0 × 1.0 cm muscular segment of the left diaphragm, which was closed by implanting a PTFE mesh (n = 5), or a Lyoplant mesh (n = 6). For control purposes (sham group, n = 2), the defect was closed directly. Each rat was examined frequently for the duration of 12 weeks. After this period, the abdomen was reopened, examined for adhesions and the left diaphragm was explanted for histological examination. RESULTS: All operated Wistar Furth rats exhibited a physiological body weight gain after the procedure. During the above period, no recurrence of CDH could be found, either radiologically or clinically. In all animals (PTFE vs. Lyoplant vs. sham group), strong adhesions of the left liver lobe to the implanted material were found. In contrast to the PTFE mesh, constant tissue remodeling and continuous neovascularisation were found in the Lyoplant group. CONCLUSION: Our results show that Lyoplant can successfully be used for the biocompatible therapy of CDH in the rat model. The extent to which it can also be used to treat congenital diaphragmatic defects must be demonstrated by further experimental and clinical studies.


Assuntos
Hérnias Diafragmáticas Congênitas , Animais , Criança , Colágeno , Humanos , Politetrafluoretileno , Próteses e Implantes , Ratos
12.
Cancers (Basel) ; 12(1)2019 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-31877753

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is amongst the most fatal malignancies and its development is highly associated with inflammatory processes such as chronic pancreatitis (CP). Since the succinate dehydrogenase subunit B (SDHB) is regarded as tumor suppressor that is lost during cancer development, this study investigated the impact of M1-macrophages as part of the inflammatory microenvironment on the expression as well as function of SDHB in benign and premalignant pancreatic ductal epithelial cells (PDECs). Immunohistochemical analyses on pancreatic tissue sections from CP patients and control individuals revealed a stronger SDHB expression in ducts of CP tissues being associated with a greater abundance of macrophages compared to ducts in control tissues. Accordingly, indirect co-culture with M1-macrophages led to clearly elevated SDHB expression and SDH activity in benign H6c7-pBp and premalignant H6c7-kras PDECs. While siRNA-mediated SDHB knockdown in these cells did not affect glucose and lactate uptake after co-culture, SDHB knockdown significantly promoted PDEC growth which was associated with increased proliferation and decreased effector caspase activity particularly in co-cultured PDECs. Overall, these data indicate that SDHB expression and SDH activity are increased in PDECs when exposed to pro-inflammatory macrophages as a counterregulatory mechanism to prevent excessive PDEC growth triggered by the inflammatory environment.

13.
Food Chem ; 289: 223-231, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30955606

RESUMO

Although the connection between protein oxidation, amyloid aggregation and diseases such as Alzheimer's is well known there is no information on such effects during preparation of beta-lactoglobulin fibrils. Different morphologies of amyloid aggregates of beta-lactoglobulin were prepared by incubation at pH 2 or pH 3.5 for up to 72 h. After 5 h, amyloid aggregates at pH 2 formed typical fibrils, which consisted of peptides. At pH 3.5, the amyloid aggregates were worm-like and consisted of intact protein. After 72 h, the building blocks at both pH values changed towards smaller peptides. The apparent tyrosine oxidation reached a maximum after 5 h at both pH values, whereas N-formylkynurenine and carbonyls increased continuously during 72 h. In case amyloid structures are used as edible material, the health related effects caused by protein oxidation needs to be considered.


Assuntos
Lactoglobulinas/química , Agregados Proteicos , Amiloide/metabolismo , Animais , Bovinos , Cromatografia em Gel , Concentração de Íons de Hidrogênio , Lactoglobulinas/metabolismo , Oxirredução , Peptídeos/análise , Temperatura , Tirosina/química
14.
Cells Tissues Organs ; 206(1-2): 106-118, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30677765

RESUMO

Polyphenols are known for their antimicrobial activity, whilst both polyphenols and the globular protein ß-lactoglobulin (bLG) are suggested to have antioxidant properties and promote cell proliferation. These are potentially useful properties for a tissue-engineered construct, though it is unknown if they are retained when both compounds are used in combination. In this study, a range of different microbes and an osteoblast-like cell line (human fetal osteoblast, hFOB) were used to assess the combined effect of: (1) green tea extract (GTE), rich in the polyphenol epigallocatechin gallate (EGCG), and (2) whey protein isolate (WPI), rich in bLG. It was shown that approximately 20-48% of the EGCG in GTE reacted with WPI. GTE inhibited the growth of Gram-positive bacteria, an effect which was potentiated by the addition of WPI. GTE alone also significantly inhibited the growth of hFOB cells after 1, 4, and 7 days of culture. Alternatively, WPI significantly promoted hFOB cell growth in the absence of GTE and attenuated the effect of GTE at low concentrations (64 µg/mL) after 4 and 7 days. Low concentrations of WPI (50 µg/mL) also promoted the expression of the early osteogenic marker alkaline phosphatase (ALP) by hFOB cells, whereas GTE inhibited ALP activity. Therefore, the antioxidant effects of GTE can be boosted by WPI, but GTE is not suitable to be used as part of a tissue-engineered construct due to its cytotoxic effects which negate any positive effect WPI has on cell proliferation.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Osteogênese/efeitos dos fármacos , Polifenóis/farmacologia , Chá/química , Proteínas do Soro do Leite/farmacologia , Adulto , Antibacterianos/química , Antioxidantes/química , Bactérias/efeitos dos fármacos , Catequina/análogos & derivados , Catequina/química , Catequina/farmacologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Masculino , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Polifenóis/química , Proteínas do Soro do Leite/química , Adulto Jovem
15.
Biomed Mater ; 11(4): 045015, 2016 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-27509486

RESUMO

Hydrogels offer several advantages as biomaterials for bone regeneration, including ease of incorporation of soluble substances such as mineralization-promoting enzymes and antibacterial agents. Mineralization with calcium phosphate (CaP) increases bioactivity, while antibacterial activity reduces the risk of infection. Here, gellan gum (GG) hydrogels were enriched with alkaline phosphatase (ALP) and/or Seanol(®), a seaweed extract rich in phlorotannins (brown algae-derived polyphenols), to induce mineralization with CaP and increase antibacterial activity, respectively. The sample groups were unmineralized hydrogels, denoted as GG, GG/ALP, GG/Seanol and GG/Seanol/ALP, and hydrogels incubated in mineralization medium (0.1 M calcium glycerophosphate), denoted as GG/ALP_min, GG/Seanol_min and GG/Seanol/ALP_min. Seanol(®) enhanced mineralization with CaP and also increased compressive modulus. Seanol(®) and ALP interacted in a non-covalent manner. Release of Seanol(®) occurred in a burst phase and was impeded by ALP-mediated mineralization. Groups GG/Seanol and GG/ALP/Seanol exhibited antibacterial activity against methicillin-resistant Staphylococcus aureus. GG/Seanol/ALP_min, but not GG/Seanol_min, retained some antibacterial activity. Eluates taken from groups GG/ALP_min, GG/Seanol_min and GG/ALP/Seanol_min displayed comparable cytotoxicity towards MG-63 osteoblast-like cells. These results suggest that enrichment of hydrogel biomaterials with phlorotannin-rich extracts is a promising strategy to increase mineralizability and antibacterial activity.


Assuntos
Antibacterianos/química , Hidrogéis/química , Polissacarídeos Bacterianos/química , Alga Marinha/química , Taninos/química , Fosfatase Alcalina/metabolismo , Anti-Infecciosos/química , Materiais Biocompatíveis/química , Regeneração Óssea , Fosfatos de Cálcio/química , Linhagem Celular , Humanos , Staphylococcus aureus Resistente à Meticilina , Testes de Sensibilidade Microbiana , Osteoblastos/citologia , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Estresse Mecânico , Termogravimetria
16.
J Neurosurg Pediatr ; 17(5): 544-51, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26799410

RESUMO

OBJECTIVE The use of adjustable differential pressure valves with gravity-assisted units in shunt therapy of children with hydrocephalus was reported to be feasible and promising as a way to avoid chronic overdrainage. In this single-center study, the authors' experiences in infants, who have higher rates of shunt complications, are presented. METHODS All data were collected from a cohort of infants (93 patients [37 girls and 56 boys], less than 1 year of age [mean age 4.1 ± 3.1 months]) who received their first adjustable pressure hydrocephalus shunt as either a primary or secondary implant between May 2007 and April 2012. Rates of valve and shunt failure were recorded for a total of 85 months until the end of the observation period in May 2014. RESULTS During a follow-up of 54.2 ± 15.9 months (range 26-85 months), the Kaplan-Meier rate of shunt survival was 69.2% at 1 year and 34.1% at 85 months; the Kaplan-Meier rate of valve survival was 77.8% at 1 year and 56% at 85 months. Survival rates of the shunt were significantly inferior if the patients had previous shunt surgery. During follow-up, 44 valves were exchanged in cases of infection (n = 19), occlusion (n = 14), dysfunction of the adjustment unit (n = 10), or to change the gravitational unit (n = 1). CONCLUSIONS Although a higher shunt complication rate is observed in infant populations compared with older children, reasonable survival rates demonstrate the feasibility of using this sophisticated valve technology. The gravitational unit of this valve is well tolerated and its adjustability offers the flexible application of opening pressure in an unpredictable cohort of patients. This may adequately address overdrainage-related complications from early in treatment.


Assuntos
Pressão do Líquido Cefalorraquidiano , Gravitação , Hidrocefalia/cirurgia , Derivação Ventriculoperitoneal/instrumentação , Derivações do Líquido Cefalorraquidiano/instrumentação , Criança , Pré-Escolar , Desenho de Equipamento , Feminino , Seguimentos , Humanos , Hidrocefalia/fisiopatologia , Lactente , Estimativa de Kaplan-Meier , Masculino , Estudos Retrospectivos , Resultado do Tratamento , Derivação Ventriculoperitoneal/efeitos adversos
17.
Food Chem ; 197(Pt A): 47-56, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26616923

RESUMO

The influence of postharvest UV-B on its own and in combination with fermentation (e.g. sauerkraut production) on formation and degradation of bioactive compounds was investigated in white cabbage, processed according to traditional Chinese fermentation methods. The pattern of polyphenols was affected by postharvest UV-B: Newly formed coumaroylglycoside, feruloylglycoside, caffeoylglycoside (up to 1 mg/g dry matter; 4 days) and quercetintriglycoside (0.4-0.5 mg/gdm; 4 days) might be related to postharvest increase in enzyme activity in the biosynthesis. Decreasing contents were observed for the glucosinolates glucobrassicin and 4-methoxyglucobrassicin, but the formation of the degradation products dihydroascorbigen and dihydro-4-methoxyascorbigen, which might be related to cell shrinking as mechanical damage. Fermentation resulted in deglycosidation of hydroxycinnamic acids. Newly generated cinnamic acid from coumaric acid aglycone was detected in fermented plant material combined with UV-B (50 µg/g). Glucosinolates and dihydroascorbigens were completely degraded. This study shows exemplary UV-B as a supplemental step to improve the nutritional quality of processed plants.


Assuntos
Brassica/química , Fermentação , Análise de Alimentos/métodos , Irradiação de Alimentos/métodos , Folhas de Planta/química , Raios Ultravioleta , Brassica/efeitos da radiação , Armazenamento de Alimentos , Glucosinolatos/análise , Indóis/análise , Folhas de Planta/efeitos da radiação , Polifenóis/análise
18.
Food Chem ; 197(Pt A): 1022-9, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26617049

RESUMO

The whey protein ß-lactoglobulin has been proposed as a transporter for covalent bound bioactive compounds in order to enhance their stability and reduce their sensory perception. The garlic derived compounds allicin and diallyl disulfide were bound covalently to the native and heat denatured protein. The binding site and the influence of the modification on the digestibility were determined by mass spectrometric analysis of the modified ß-lactoglobulin. Further, the conformation of the modified protein was assessed by circular dichroism and dynamic light scattering. The free thiol group of Cys(121) turned out to be the major binding site. After proteolysis with trypsin at pH 7 but not with pepsin at pH 2, a limited transfer to other cysteinyl residues was observed. The covalently bound ligands did not mask any proteolytic cleavage sites of pepsin, trypsin or chymotrypsin. The modified ß-lactoglobulin showed a native like conformation, besides a moderate loosening of protein folding. The covalent binding of organosulfur compounds to ß-lactoglobulin provides a bioactive ingredient without impairing the digestibility and functional properties of the protein.


Assuntos
Compostos Alílicos/química , Dissulfetos/química , Lactoglobulinas/química , Ácidos Sulfínicos/química , Quimotripsina/metabolismo , Dicroísmo Circular , Alho , Conformação Molecular , Pepsina A/metabolismo , Conformação Proteica , Desnaturação Proteica , Dobramento de Proteína , Compostos de Sulfidrila/química , Tripsina/metabolismo
19.
J Mol Recognit ; 28(11): 656-66, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26038095

RESUMO

The lipocalin ß-lactoglobulin (ß-LG) exists in different natural genetic variants--of which ß-LG A and B are predominant in bovine milk. At physiological conditions the protein dimerizes--building homodimers of ß-LG A and ß-LG B and heterodimers of ß-LG AB. Although ß-LG is one of the most intensely characterized lipocalins, the interaction behavior of ligands with hetero- and homodimers of ß-LG is largely unknown. The present findings revealed significant differences for hetero- and homodimers regarding ligand binding capacity as tested with a model ligand (i.e. surface binding (-)-epigallocatechin gallate (EGCG)). These findings were confirmed using FT-IR, where the addition of EGCG influenced the ß-sheet backbone of homodimer A and B with significantly higher intensity compared to heterodimer AB. Further, shape analysis by SAXS revealed oligomerization of both types of dimers upon addition of EGCG; however, homodimer A and B produced significantly larger aggregates compared to the heterodimer AB. In summary, the present study revealed that EGCG showed significantly different interaction reactivity (binding sites, aggregation size and conformational changes) to the hetero and homodimers of ß-LG in the order ß-LG A > B > AB. The results suggest that conformational differences between homodimers and heterodimers strongly influence the EGCG binding ability. This may also occur with other polyphenols and ligands of ß-LG and gives not only important information for ß-LG binding studies, but may also apply for polymorphisms of other self-aggregating lipocalins.


Assuntos
Catequina/análogos & derivados , Lactoglobulinas/química , Lactoglobulinas/metabolismo , Ligação Proteica/fisiologia , Multimerização Proteica/fisiologia , Animais , Sítios de Ligação/fisiologia , Catequina/química , Catequina/metabolismo , Bovinos , Ligantes , Leite/química , Leite/metabolismo , Estrutura Secundária de Proteína , Espalhamento a Baixo Ângulo , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Difração de Raios X/métodos
20.
J Inherit Metab Dis ; 37(5): 851-61, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24658845

RESUMO

A child of consanguineous parents of Pakistani origin developed jaundice at 5 weeks and then, at 3 months, irritability, a prolonged prothrombin time, a low albumin, and episodes of hypoglycaemia. Investigation showed an elevated alanine aminotransferase with a normal γ-glutamyl-transpeptidase. Analysis of urine by electrospray ionisation tandem mass spectrometry (ESI-MS/MS) showed that the major peaks were m/z 480 (taurine-conjugated 3ß-hydroxy-5-cholenoic acid) and m/z 453 (sulphated 3ß-hydroxy-5-cholenoic acid). Analysis of plasma by gas chromatography-mass spectrometry (GC-MS) showed increased concentrations of 3ß-hydroxy-5-cholenoic acid, 3ß-hydroxy-5-cholestenoic acid and 27-hydroxycholesterol, indicating oxysterol 7 α-hydroxylase deficiency. The patient was homozygous for a mutation (c.1249C>T) in CYP7B1 that alters a highly conserved residue in oxysterol 7 α-hydroxylase (p.R417C) - previously reported in a family with hereditary spastic paraplegia type 5. On treatment with ursodeoxycholic acid (UDCA), his condition was worsening, but on chenodeoxycholic acid (CDCA), 15 mg/kg/d, he improved rapidly. A biopsy (after 2 weeks on CDCA), showed a giant cell hepatitis, an evolving micronodular cirrhosis, and steatosis. The improvement in liver function on CDCA was associated with a drop in the plasma concentrations and urinary excretions of the 3ß-hydroxy-Δ5 bile acids which are considered hepatotoxic. At age 5 years (on CDCA, 6 mg/kg/d), he was thriving with normal liver function. Neurological development was normal apart from a tendency to trip. Examination revealed pes cavus but no upper motor neuron signs. The findings in this case suggest that CDCA can reduce the activity of cholesterol 27-hydroxylase - the first step in the acidic pathway for bile acid synthesis.


Assuntos
Ácido Quenodesoxicólico/uso terapêutico , Hepatopatias/tratamento farmacológico , Hepatopatias/genética , Esteroide Hidroxilases/deficiência , Esteroide Hidroxilases/genética , Ácidos e Sais Biliares/sangue , Ácidos e Sais Biliares/urina , Consanguinidade , Família 7 do Citocromo P450 , Humanos , Lactente , Fígado/patologia , Hepatopatias/enzimologia , Masculino , Erros Inatos do Metabolismo/tratamento farmacológico , Erros Inatos do Metabolismo/genética
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