首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
Correlations between total phenolic and mineral contents with antioxidant activities of pulps and peels from eight banana (Musa sp.) cultivars were studied. The total phenolic contents were determined using Folin-Ciocalteu colorimetric method, and antioxidant activities were measured using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay and ferric reducing antioxidant potential (FRAP) assay. The highest total phenolic content (76.37 ± 1.79 mg GAE/g d.w.) was obtained from the freeze-dried extract of fresh pulps of Raja cultivar. The maximum activity of DPPH (19.39 ± 0.15 mg TE/g d.w.) was recorded for the chloroform extract of dried peels of Mas cultivar. Meanwhile, the highest activity of FRAP was shown by most of the chloroform extracts of dried pulps, dominated by Awak cultivar (22.57 ± 0.13 mg TE/g d.w.). With few exceptions, peel extracts exhibited higher total phenolic content and stronger antioxidant activities than that of the pulps. Very weak correlation between total phenolic content and FRAP activity was observed, yet it is higher (r2 = 0.1614, p < 0.0001) than that of total phenolic content and DPPH activity (r2 = 0.02339, p < 0.05). A moderate correlation between DPPH and FRAP activities was obtained (r2 = 0.3533, p < 0.0001). For mineral analysis, potassium (K) is the major element found in both fresh pulps and peels followed by P, Mg and Na. Fresh peels of Raja consisted the highest amount of K (1387.5 mg/100 g f.w.). With exception of Mn, no correlation was found between mineral content and antioxidant activity. A moderate correlation between Mn content and DPPH activity was observed (r2 = 0.2855, p < 0.0001).  相似文献   

2.
Eight fruit beverages containing grape, orange and apricot, with/without iron and/or zinc and with/without milk added were analyzed for total antioxidant capacity (ORAC and TEAC methods), ascorbic acid content, and total polyphenols. The influence of cold storage (2-4 °C) during the product shelf-life (135 days) and antioxidant capacity after an in vitro gastrointestinal digestion were evaluated. Antioxidant capacity for all beverages together increased significantly (p < 0.05) at the end of storage (16.4% and 12.8% for ORAC and TEAC, respectively), whereas ascorbic acid remained stable. Regarding in vitro digestion, antioxidant values of bioaccessible fractions of fruit beverages increased (p < 0.05) 59% and 20% for ORAC and TEAC, respectively, while ascorbic acid and polyphenol content fell 36% and 16%, respectively (p < 0.05). Supplementation of fruit beverages with milk and/or Fe/Zn did not modify total antioxidant capacity of samples during either cold storage or during in vitro digestion.  相似文献   

3.
Hydrophilic extracts from different parts including leaves, stalks, seeds, flowers and sprouts of 3 Amaranthus species (Amaranthus hypochondriacus, Amaranthus caudatus and Amaranthus cruentus) were characterized for their phytochemical profiles including the phenolics and betacyanins by UHPLC and LC–ESI–MS, and their antioxidant activities by FRAP and ORAC assays. The main betacyanins in Amaranthus samples were identified to be amaranthine and isoamaranthine. Eleven phenolic compounds (gallic acid, protocatechuic acid, chlorogenic acid, gentistic acid, 2,4-dihydroxybenzoic acid, ferulic acid, salicylic acid, rutin, ellagic acid, kaempferol-3-rutinoside and quercetin) were identified in the extracts of different parts of Amaranthus. The total phenolic content (TPC) ranged from 1.04 to 14.94 mg GAE/g DW; the total flavonoid content (TFC) ranged from 0.27 to 11.40 mg CAE/g DW; while the total betalain content (TBC) ranged from 0.07 to 20.93 mg/100 g DW. FRAP values ranged from 0.63 to 62.21 μmol AAE/g DW and ORAC ranged from 30.67 to 451.37 μmol TE/g DW. The leaves of Amaranthus showed the highest TPC, TFC, TBC, FRAP and ORAC values; while the seeds and stalks the lowest. There was a strong correlation between TPC, TBC, TFC and the antioxidant activity. The result suggests that all parts of the Amaranthus plant can be a good source of antioxidants.  相似文献   

4.
Leaves of the Japanese Camellia sinensis cultivar “Yabukita” were used for the elucidation of structural patterns of carotenoid cleavage enzymes. The enzymes were isolated from fresh tea leaves in active form and purified to single band in SDS PAGE gels. Subsequently, the specific activity of the carotenoid cleavage enzymes was tested and the positive fractions selected for further analysis. The phosphate content of the purified enzyme was elucidated by three different methods: phosphatase assays, fluorescence marker kits and by measuring ammoniumheptamolybdate complexes after incineration of the samples. In all cases phosphorylations of the respective samples could be detected, thus giving evidence for an overall increase of the phosphorylations level of proteins in C. sinensis from spring (1.84 μg/mg) to autumn (2.39 μg/mg). Consequently, carotenoid cleavage enzymes isolated in autumn also showed higher phosphorylation levels, which may as well correspond to changes on the functional level between spring (Michaelis Constant (Km) = 9.45 μmol/L) and autumn (Km = 17.16 μmol/L).  相似文献   

5.
The raw and processed seeds of the underutilized legume, Vigna vexillata (L.) A. Rich were extracted with 70% acetone and used for the evaluation of its antioxidant potential. The different heat treatments included dry heating, soaking followed by autoclaving with 0.1% sodium bicarbonate, soaking followed by autoclaving and autoclaving without soaking. The raw seed extract contained higher levels of total phenolics (11.7 g/100 g) and tannins (5.9 g/100 g) than the processed seed extracts. The extracts were further evaluated for their antioxidant activities using FRAP, Fe2+ chelation, phosphomolybdenum reduction, DPPH and ABTS+ radical scavenging, antihemolytic and β-carotene/linoleic acid emulsion systems. In general, the raw seed extracts were the most potent antioxidant suppliers and free radical scavengers. Interestingly, among the various processing methods, acetone extract of dry heated seed sample registered higher antihemolytic activity (86.2%) at the concentration of 500 μg/ml, whereas, in β-carotene/linoleic acid emulsion system, the extracts of raw seeds and the presoaked seeds followed by autoclaving with 0.1% sodium bicarbonate exhibited higher and comparable activity than other processed seed extracts.  相似文献   

6.
Blueberry is an important source of anthocyanins, which are highly colored substances recognized for their antioxidant activity. One of the drawbacks of using anthocyanins as food colorant is their low stability. The objective of this study was to evaluate the variations found in color and concentration of the compounds (which produce the color) on spray-dried powders, obtained from blueberry extracts with added mesquite gum. Ethanolic blueberry extracts were concentrated until reaching 35% of soluble solids. They were then spray-dried using mesquite gum as an encapsulating agent at 140 and 160 °C of air inlet temperature and 8.5, 9.1 and 9.6 mL/min of feeding rates. The lowest losses in the content of total phenolics, total anthocyanins, and color of the samples were found in samples dried at 140 °C and 9.1 mL/min. The microencapsulates that were stored for 4 weeks at 4 °C in the absence of light presented low degradation of phenolics (10%), anthocyanins (7%) and antioxidant activity (15%). Final color values were L = 39.87, C = 47.83 and H° = 28.59, with a total color difference ΔE = 5.  相似文献   

7.
The antioxidant properties of various kinds of the traditional Polish alcoholic beverage nalewka were investigated using electron paramagnetic resonance (EPR), nuclear magnetic resonance (NMR) and ultraviolet–visible (UV–vis) spectroscopy. The antioxidant capacity was measured by EPR spectroscopy in μmol Trolox (TE) in a 100 mL nalewka sample. The total phenolic content was measured by Folin–Ciocalteu (FC) assays while aromatic proton content (Har) was determined by NMR spectroscopy; subsequently the correlation among these values was explored. All of the investigated nalewkas exhibited antioxidant properties. The values of Trolox equivalent antioxidant capacity (TEACDPPH) were in the range 45–1045 μmol TE/100 mL. It was found that the value of the TEACDPPH corresponded to the TP (r = 0.96) and Har (r = 0.95). Moreover, the TEACDPPH values depended on the kinds of fruits used for nalewkas’ preparation.  相似文献   

8.
Different kinds of chocolates produced in Serbia were analyzed regarding total polyphenol, flavonoid and proanthocyanidin content using spectrophotometric methods. Flavan-3ols and methylxanthines in all samples were determined with RP-HPLC. DPPH, FRAP, ABTS and ORAC assays were applied for measuring antioxidant capacity. The average of all four antioxidant tests for each cocoa product was used for calculating antioxidant potency composite index (ACI). Obtained results for all four assays have shown that antioxidant capacity of analyzed chocolate/cocoa extracts followed cocoa, polyphenol, flavonoid, and proanthocyanidin contents. Although the addition of raspberries to dark chocolates had no significant influence on their total polyphenol, flavonoid and proanthocyanidin contents, statistical analysis showed that there was significant increase in the antioxidant capacity of dark chocolates with raspberry compared to plain dark chocolates (p = 0.007). Overall range for theobromine content varied from 5.5 to 22.3 mg/g depending on the product type, while the content of caffeine was 13–30 times lower in all analyzed cocoa products. In addition, correlation between antioxidant potency composite index and declared percentage of cocoa was high (R2 = 0.798, p < 0.05) and indicated that declared cocoa content was a reliable indication for antioxidant capacity of chocolates produced in Serbia.  相似文献   

9.
In this paper an integrated approach in assessment of the population exposure from various sources of total mercury (THg) oral intake in the Czech Republic is presented. The information on total mercury levels in diet, drinking water, surface urban soil and body fluids and tissues stem from the Czech national Environmental Health Monitoring System (EHMS) operated since 1994. The THg concentration was determined by the special atomic absorption spectrophotometer AMA 254. The data on THg content in food from the sales network were collected in 12 cities. The estimated average dietary intake representing more than 95% of weight of usual diet composition ranged 1–2% of the JECFA/FAO WHO provisional tolerable weekly intake (PTWI) value for total mercury (5 μg/kg b.w./week). Data on drinking water quality stem from the nationwide monitoring database. The content of THg in drinking water is generally low; only 0.2% of the Czech population supplied with drinking water from the distribution networks (total of 92% of the population) has a mercury intake from drinking water higher than 1% PTWI and not exceeding 5% PTWI. The estimation of potential mercury intake by unintentional consumption of soil in small children was based on THg content in surface soil of a total of 324 nursery schools in 24 cities and towns. Median value was 0.16 mg/kg. Human biomonitoring was performed in 9 Czech cities. In 2007, the mercury median values in blood of adults (N = 412) were 0.85 and 0.89 μg/l in males and in females, respectively; urine median value in adults was 1.10 μg/g creatinine. In 2008, the blood median value in children (N = 324) amounted to 0.35 μg/l; urine median value is 0.16 μg/g creatinine. In children's hair the median THg value was 0.18 μg/g. The correlation between fish consumption and blood THg levels was observed in both adults and children. Also the biomonitoring outputs did not reveal a substantial burden of the population.  相似文献   

10.
Plasmodium falciparum Liver Stage Antigen 1 (LSA-1) is a pre-erythrocytic stage antigen. Our LSA-1 vaccine candidate is a recombinant protein with full-length C- and N-terminal flanking domains and two of the 17 amino acid repeats from the central repeat region termed “LSA-NRC.” We describe the first Phase I/II study of this recombinant LSA-NRC protein formulated with either the AS01 or AS02 adjuvant system. We conducted an open-label Phase I/II study. Thirty-six healthy malaria-naïve adults received one of four formulations by intra-deltoid injection on a 0 and 1 month schedule; low dose (LD) LSA-NRC/AS01:10 μg LSA-NRC/0.5 ml AS01 (n = 5), high dose (HD) LSA-NRC/AS01: 50 μg LSA-NRC/0.5 ml AS01 (n = 13); LD LSA-NRC/AS02: 10 μg LSA-NRC/0.5 ml AS02 (n = 5) and HD LSA-NRC/AS02: 50 μg LSA-NRC/0.5 ml AS02 (n = 13). Two weeks post-second immunization, the high dose vaccinees and 6 non-immunized infectivity controls underwent experimental malaria sporozoite challenge.  相似文献   

11.
Phenolic compound composition and antioxidant capacity of four Oenocarpus distichus Mart. (bacaba-de-leque) genotypes were determined. In order to set the parameters for phenolic compound extraction, the effect of methanol concentration and extraction time on the reducing power of the extracts was evaluated using the surface response methodology. The optimal conditions were: a 60:40 methanol:water (v/v) solution and 11 min of extraction. Extracts were analyzed by ultra-high performance liquid chromatography with diode array detection and by ultra-high performance liquid chromatography coupled to mass spectrometry. Eleven substances were identified, of which six were quantified. Rutin was the major compound in bacaba-de-leque genotypes (15.2–56.8 μg.g−1) followed by epicatechin (15.5–21.2 μg.g−1). The Black-03 genotype had the highest amounts of all phenolic compounds and the highest antioxidant capacity by DPPH and ORAC assays, indicating that this genotype may be selected in breeding programs to obtain cultivars with higher phenolic compound contents and antioxidant capacity. Moreover, the results indicated that bacaba-de-leque has great potential as a novel supplier of phenolic acids and flavonoids to human diet, with levels comparable to or higher than other fruits belonging to the same family, such as açaí.  相似文献   

12.

Background and aims

We evaluated the immunogenicity of the 7-valent pneumococcal conjugate vaccine (PCV7), and its impact on pneumococcal carriage in Venezuelan children at high risk for invasive pneumococcal disease (IPD).

Methods

82 children (age 2–59 months) with sickle cell anemia (n = 22), chronic heart disease (n = 19), HIV infection (n = 12), immune-suppressive therapy (n = 11) and other IPD-predisposing conditions (n = 18) were vaccinated with PCV7 according to CDC-recommended age-related immunization schedules. Blood samples were taken to determine the concentration of IgG antibody, and nasopharyngeal swabs were obtained to isolate Streptococcus pneumoniae, before the first vaccine dose and 1 month after completion of the vaccination schedule.

Results

Pneumococcal carriage prior to the first immunization was 27% (n = 22), with the most frequently carried serotypes being vaccine serotypes 6B (22%) and 14 (13%). One month after completion of the vaccination scheme pneumococcal carriage was 22% (n = 17), dominated by non-vaccine serotypes 19A (24%) and 7F (12%). Before immunization, 65% of the subjects had IgG antibody titers >0.35 μg/mL for five serotypes tested. Post-vaccination, 100% of the subjects showed titers >1.0 μg/mL for all PCV7 serotypes with geometric mean concentrations (GMC) ranging from 1.75 μg/mL (serotype 23F) to 17.16 μg/mL (serotype 14). Children previously colonized with serotype 6B had a significantly lower GMC to this serotype following immunization than children not carrying 6B prior to the first PCV dose (p < 0.05).

Conclusions

PCV7 is highly immunogenic in Venezuelan children at high-risk for IPD. Vaccination was associated with an immediate shift in nasopharyngeal carriage toward non-PCV7 serotypes. Finally, we observed serotype-specific hyporesponsiveness to immunization after natural carriage with the same serotype in high-risk children.  相似文献   

13.
Milk fat chemical composition of yak breeds in China   总被引:1,自引:0,他引:1  
The present study was undertaken to evaluate the fatty acid composition, conjugated linoleic acid (CLA) and cholesterol contents in the milk from three yak breeds, Maiwa yak (n = 24), Zhongdian yak (n = 16) and Gannan yak (n = 16) and two yak crossbreeds, Maiwa yak × yellow cattle (n = 16) and Gannan yak × yellow cattle (n = 16). Statistically significant differences (P < 0.05) in the proportions of individual milk fatty acids were observed among the three yak breeds. The proportion of saturated fatty acids (SFAs) and monounsaturated fatty acids (MUFAs) did not differ statistically (P > 0.05) among the three yak breeds. However, the percentage of total polyunsaturated fatty acids (PUFAs) in Zhongdian yak milk (4.82%) was significantly higher (P < 0.01) than in Maiwa (3.99%) and Gannan (3.68%) yak milks. The contents of α-linolenic acid (C18:3) and cis-9, trans-11 conjugated linoleic acid (CLA) were significantly different (P < 0.05) among the three yak breeds. The total SFAs, MUFAs and PUFAs were not significantly different (P > 0.05%) between the two yak crossbreeds. The cholesterol contents in milk samples from yak breeds and yak crossbreeds were found to be in the range 12.32-16.17 mg/100 g. Cholesterol contents in milk samples from yak breeds and yak crossbreeds were positively correlated with their fat contents.  相似文献   

14.
Brasenia schreberi Gmel. (Cabombaceae) is an aquatic plant that grows in eastern Asia, Australia, Africa, and North and Central America. B. schreberi leaf extracts were obtained by sequential solvent extraction with dichloromethane, methanol, and water. The antioxidant potential of each extract was assessed by using the oxygen radical absorbance capacity (ORAC) assay. With this method, methanol and water extracts were found to be active with mean ± standard deviation values of 7 ± 2 and 5.1 ± 0.5?μmol Trolox? equivalents (TE)/mg, respectively. Two major phenolic compounds, quercetin-7-O-β-D-glucopyranoside and gallic acid, were respectively isolated from the methanolic and water extracts. Both compounds exhibited antioxidant activities, in particular quercetin-7-O-β-D-glucopyranoside (ORAC value, 18 ± 4 μmol TE/μmol). In contrast to its well-known antioxidant homologue quercetin, quercetin-7-O-β-D-glucopyranoside does not inhibit growth of human fibroblasts (WS-1) or murine macrophages (RAW 264.7). Some flavonoids have been reported to possess beneficial effects in cardiovascular and chronic inflammatory diseases associated with overproduction of nitric oxide. Quercetin-7-O-β-D-glucopyranoside possesses anti-inflammatory activity, inhibiting expression of inducible nitric oxide synthase and release of nitric oxide by lipopolysaccharide-stimulated RAW 264.7 macrophages in a dose-dependent manner. Quercetin-7-O-β-D-glucopyranoside also inhibited overexpression of cyclooxygenase-2 and granulocyte macrophage-colony-stimulating factor.  相似文献   

15.
The objectives of this study were to: (1) determine the dosing range necessary to produce serum levels of dieldrin in mice representative of human body burdens; and (2) define the effect of developmental exposure to environmentally relevant concentrations of dieldrin on mammary gland development. Sexually mature female BALB/c mice (n=140) were randomly assigned to receive vehicle, 0.45, 2.25, 4.5, and 22.5 μg dieldrin/g body weight (BW)/day. Serum levels of dieldrin were quantified by gas chromatography in pooled samples (n=4/treatment group). Target levels of 10-30 ng/ml were achieved in 0.45 and 2.25 μg/g dose groups by the end of 2 weeks of treatment. Vehicle or dieldrin (0.45, 2.25, and 4.5 μg/g BW) was administered weekly to sexually mature female BALB/c mice (n=48) throughout mating, pregnancy, and lactation. Treatments had no effect on fertility parameters in dams or mammary gland morphology at sexual maturity. Developmental exposure to dieldrin has no effect on mammary gland development in aged BALB/c mice.  相似文献   

16.
This study aimed to: (1) measure lead contents in the surface enamel of two populations consisting of 4-6-year-old children, one from an apparently uncontaminated area (Ribeirão Preto, São Paulo State, SP, Brazil, n=247) and the other from an area notoriously contaminated with lead (Bauru, São Paulo State, Brazil, n=26); (2) compare biopsy depths between the two populations; (3) correlate biopsy depth with lead content; (4) stratify samples according to biopsy depth to compare lead contents in samples from similar biopsy depths. A surface enamel acid-etch microbiopsy was performed in vivo on a single upper deciduous incisor for each sample. Lead was measured by graphite furnace atomic absorption spectrometry (GFAAS) while phosphorus was measured colorimetrically to establish biopsy depth. Samples from both populations were classified into categories of similar biopsy depths based on biopsy depth quartiles. Median lead contents were statistically different between the Ribeirão Preto population (206 μg/g, range: 5-1399 μg/g) and the Bauru population (786 μg/g, range: 320-4711 μg/g) (p<0.001); however, biopsy depth did not differ between the Ribeirão Preto (3.9 μm, Standard Deviation, SD=0.9) and Bauru (3.8 μm, SD=0.9) populations (p=0.7940). Pearson's correlation coefficient for biopsy depths versus log10 lead values was −0.29 for Ribeirão Preto and −0.18 for Bauru. Lead contents were statistically different between the two populations for all quartiles of biopsy depth. These findings suggest that lead accumulated in the surface enamel of deciduous teeth is linked to the environment in which people reside, indicating that this tissue should be further explored as an accessible biomarker of lead exposure.  相似文献   

17.
Wild asparagus, Asparagus acutifolius L., produces edible spears used in local diets of Mediterranean countries for millenia. Recently, interest has risen for its cultivation as frugal crop for niche markets, but only limited information exists on the nutritional values of this vegetable. In this paper, the nutritional values and metabolic profile (i.e. moisture content, total proteins, lipids and phenols, folic and ascorbic acids, ribose, arabinose, xylose, fructose, mannose, glucose, galactose, total and free aminoacids, and fatty acid composition) and radical scavenging capacities of spears of A. acutifolius from the Caserta area (southern Italy) were compared to those of the cultivated Asparagus officinalis L. On a fresh weight basis, proteins (4.83 vs. 3.62 g/100 g), essential amino acids (184.08 vs. 78.13 mg/100 g) and lipids (0.90 vs. 0.33 g/100 g) were higher in wild asparagus. Among the fatty acids, the two essential n-6 linoleic and n-3 alpha-linolenic, and palmitic acids were the most abundant in both species, representing about 90% of the total acids analysed. A. acutifolius contained comparable amounts of pentoses such as ribose (0.13 vs. 0.15 g/100 g) and xylose (0.17 vs. 0.14 g/100 g), and hexoses such as galactose (0.21 vs. 0.19 g/100g) and fructose (0.17 vs. 0.17 g/100 g), lower arabinose (0.27 vs. 0.39 g/100 g) and higher mannose (0. 90 vs. 0.49 g/100 g) and glucose (2.52 vs. 1.21 g/100 g) content, compared to A. officinalis. Folic acid was lower in A. acutifolius (47.5 vs. 80.6 μg), while ascorbic acid was more than fivefold higher (117 vs. 23 mg/100 g). Phenolic compounds were more abundant in A. acutifolius spears (41.97 vs. 27.62 mg/100 g) as was the radical scavenging activity against DPPH radical and nitric oxide. A. acutifolius appears nutritionally interesting for its high content in dry matter, proteins, lipids, phenols and for its strong antioxidant properties, raising interest for this potential new crop.  相似文献   

18.
Occupational exposure of dairy workers to particulate matter (PM) and endotoxin has been considered by some to be of potential concern. This paper reports personal exposure concentrations of PM (μg/m3) and endotoxin (EU/m3) for 226 workers from 13 California dairies. Arithmetic mean personal concentrations for PM2.5, inhalable PM and endotoxin were 48 μg/m3 (N = 222), 987 μg/m3 (N = 225) and 453 EU/m3 (N = 225), respectively. Using mixed effects models, time spent re-bedding of freestall barns versus any other job conducted on a dairy led to the highest exposure for PM2.5, inhalable PM, and endotoxin. Personal exposure concentrations were found to be greater than those reported for ambient area based concentrations at the same dairies. A pseudo R-square approach revealed that one area based measure combined with time spent performing tasks explained a significant portion of variation in personal exposure concentrations.  相似文献   

19.
Solanum sisymbriifolium Lam. (Litchi tomato) is grown ornamentally, and in Europe it is used as a trap crop for management of the potato cyst nematode (PCN). Its berries are edible, but little is known about their nutritional content. If more was known about their nutritional value this could provide incentive to grow it as a food crop. Phytonutrient content was characterized in berries from four varieties and four synthetic breeding lines developed to have reduced spininess. Litchi tomatoes contained 6.8–10.4 mg of total phenolics per g dry weight. Antioxidants measured by FRAP ranged from 148 to 242 μmol TE/g DW. HPLC analysis showed chlorogenic acid (1856–4385 μg/g DW) was the most abundant phenylpropanoid. Ascorbic acid ranged from 2042 to 4511 μg/g DW. The yellow/orange flesh color was due to carotenoids, with β-carotene the most abundant (204–633 μg/g DW). Soluble protein in Litchi tomato ranged from 86.9 to 120.9 mg/g. Of the cultivated Litchi tomato varieties analyzed, SS91 had the highest amount of antioxidant activity, ascorbic acid, chlorogenic acid and β-carotene. These results suggest that Litchi tomato fruits can be a good source of phytonutrients, expanding the plant's functionality beyond its use as a PCN trap crop.  相似文献   

20.
Recurrent acute otitis media (AOM), frequently caused by Streptococcus pneumoniae, is a major paediatric health problem. A reduced antibody response against pneumococcal polysaccharides may contribute to an increased susceptibility to AOM. Using a multiplex bead-based assay we measured IgG, IgG1 and IgG2 levels against 11 pneumococcal polysaccharides in serum samples from 166 children below 3 years of age with a history of at least 3 episodes of acute otitis media receiving ventilation tubes, and 61 healthy controls. Pneumococcal serotype specific IgG was also determined in 144 middle ear effusion samples. Pneumococcal serotype specific IgG, IgG1 and IgG2 levels were similar in children with or without AOM, except for IgG and IgG1 levels against serotype 5, which were significantly higher in children with a history of frequent AOM (IgG: 137.5 μg/ml vs. 84.0 μg/ml; p = 0.02; IgG1: 24.5 μg/ml vs. 18.2 μg/ml; p = 0.05). The age-related development of pneumococcal serotype-specific IgG, IgG1 and IgG2 levels was similar in children with or without a history of AOM. Pneumococcal serotype specific IgG was present in middle ear effusion and these levels correlated significantly with serum titres. Children with a history of frequent AOM receiving ventilation tubes do not have a deficient IgG, IgG1 or IgG2 response against pneumococcal polysaccharides, either induced by vaccination or due to natural exposure. The strong correlation between IgG levels in serum and the middle ear suggests parenteral pneumococcal conjugate vaccination induces antibodies in the middle ear which may therefore contribute to reducing the burden of AOM.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号