| 1. |
- Danielsson Niemi, Liza, 1976-
(författare)
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Host ligands and oral bacterial adhesion : studies on phosphorylated polypeptides and gp-340 in saliva and milk
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Infectious diseases e.g. gastric ulcer, caries and perodontitis, are caused by bacteria in a biofilm. Adhesion of bacteria to host ligands e.g. proteins, polypeptides and glycoproteins, is a key event in biofilm formation and colonization of surfaces such as mucosa and tooth tissues. Thus, host ligands could contribute to the susceptibility to infectious diseases. The general aim of this doctoral thesis was to study the effect of phosphorylated polypeptides and gp-340 in saliva and milk on oral bacterial adhesion and aggregation. Statherin is a non-glycosylated, phosphorylated polypeptide in saliva. The polypeptide inhibits precipitation and crystal growth of calcium phosphate and mediates adhesion of microorganisms. By using a hybrid peptide construct, the domain for adhesion of Actinomyces isolated from human infections and from rodents was found to reside in the C-terminal end, and the adhesion was inhibitable. With alanine substitution the peptide recognition epitope in the C-terminal end was delineated to Q and TF, where QAATF was an optimal inhibitory peptide. In contrast, human commensal Actinomyces bound to the middle region in a non-inhibitable fashion. Gp-340 is another protein in saliva, and it is a large, multifunctional glycoprotein. Four novel size variants (I-IV) of salivary gp-340 were distinguished within individuals, and their glycoforms were characterized. All four size variants were identical in the N-terminal amino acid sequence and shared core carbohydrates. Low-glyco lung gp-340, high-glyco saliva gp-340, and size variants I-III aggregated bacteria differently. Human milk, which shares many traits with saliva, could inhibit adhesion of Streptococcus mutans to saliva-coated hydroxyapatite (s-HA), a model for teeth, in an individually varying fashion. Human milk caseins, lactoferrin, secretory IgA, and IgG inhibited the binding avidly. By using synthetic peptides the inhibitory epitope in b-casein was mapped to a C-terminal stretch of 30 amino acids. Inhibition by human milk, secretory IgA and the b-casein-derived inhibitory peptide was universal among a panel of mutans streptococci. The main conclusions are: (i) statherin mediates differential binding of commensal versus infectious Actinomyces strains with small conformation-dependent binding epitopes, (ii) salivary gp-340 has individual polymorphisms that at least affect binding of bacteria, (iii) human milk inhibits S. mutans adhesion to s-HA in an individually varying fashion, and the C-terminal end of human milk β-casein is one inhibitory component. Together these results suggest that the studied host ligands can influence the composition of the oral biofilm. Statherin may protect the host from colonization of bacteria associated with infections. Gp-340 size variants may affect functions related to host innate immune defences such as interactions with a wide array of bacteria, and human milk may have a protective effect in infants from colonization of mutans streptococci.
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| 2. |
- Johansson, Ingegerd, et al.
(författare)
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Milk and oral health
- 2011
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Ingår i: Milk and Milk Products in Human Nutrition. - : S. Karger. ; , s. 55-66
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Konferensbidrag (refereegranskat)abstract
- Oral health includes freedom from disease in the gums, the mucosa and the teeth. There has been a striking reduction in dental caries and periodontitis in industrialized countries, although the proportion with severe disease has remained at 10-15%, and the prevalence increases in less developed countries. If left untreated, these diseases may lead to pain, and impaired quality of life and nutritional status. Prevention and treatment need, besides traditional implementation of proper oral hygiene, sugar restriction and use of fluoride, newer cost-effective strategies. Non-sweetened dairy products, which are proven non-cariogenic, or specific bioactive components from alike sources might prove to be part of such strategies. Thus, milk proteins, such as bovine and human caseins and lactoferrin, inhibit initial attachment of cariogenic mutans streptococci to hydroxyapatite coated with saliva or purified saliva host ligands. In contrast, both bovine and human milk coated on hydroxyapatite promotes attachment of commensal Actinomyces naeslundii and other streptococci in vitro, and phosphorylated milk-derived peptides promote maintenance of tooth minerals, as shown for the β-casein-derived caseino-phosphate peptide. Observational studies are promising, but randomized clinical trials are needed to reveal if dairy products could be a complementary treatment for oral health.
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| 3. |
- Johansson, Ingegerd, et al.
(författare)
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Snacking habits and caries in young children
- 2010
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Ingår i: Caries Research. - : S. Karger AG. - 0008-6568 .- 1421-976X. ; 44:5, s. 421-430
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Tidskriftsartikel (refereegranskat)abstract
- Dental caries is caused by a combination of infection and diet. This disease, if left untreated, may lead to pain, and impair the quality of life, nutritional status and development of young children. The objective was to investigate the association between snacking and caries in a population at high risk of dental caries. American preschool children (n = 1,206) were recruited in the offices of paediatricians. Data on sociodemographic characteristics, oral hygiene, breast-feeding, use of bottle and snacking were collected by questionnaire. Plaque presence, the number of teeth and their caries status (deft) were scored. The children sampled were 61% Black, 27% White and 10% Asian. Of the 1- to 2-, 2- to 3- and 3- to 4-year-old children, 93.8, 82.4 and 77.3% were caries free, and their mean caries scores were 0.16, 0.58 and 0.93, respectively. Multivariate partial least squares (PLS) modelling revealed plaque presence, lowest income, descriptors for tooth exposure time (number of teeth and age) and cariogenic challenge (total intake of sugar-containing snacks and chips/crisps, and chips intake with a sugar-containing drink) to be associated with more caries. These differences were also found in univariate analyses; in addition, children who continued breast-feeding after falling asleep had significantly higher deft values than those who did not. PLS modelling revealed that eating chips clustered with eating many sweet snacks, candies, popcorn and ice cream. We conclude that, in addition to the traditional risk indicators for caries - presence of plaque, sugar intake and socioeconomic status -, consumption of chips was associated with caries in young children.
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| 4. |
- Lif Holgerson, Pernilla, et al.
(författare)
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Mode of birth delivery affects oral microbiota in infants
- 2011
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Ingår i: Journal of Dental Research. - : SAGE Publications. - 0022-0345 .- 1544-0591. ; 90:10, s. 1183-1188
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Tidskriftsartikel (refereegranskat)abstract
- Establishment of the microbiota of the gut has been shown to differ between infants delivered by Caesarian section (C-section) and those delivered vaginally. The aim of the present study was to compare the oral microbiota in infants delivered by these different routes. The oral biofilm was assayed by the Human Oral Microbe Identification Microarray (HOMIM) in healthy three-month-old infants, 38 infants born by C-section, and 25 infants delivered vaginally. Among over 300 bacterial taxa targeted by the HOMIM microarray, Slackia exigua was detected only in infants delivered by C-section. Further, significantly more bacterial taxa were detected in the infants delivered vaginally (79 species/species clusters) compared with infants delivered by C-section (54 species/species clusters). Multivariate modeling revealed a strong model that separated the microbiota of C-section and vaginally delivered infants into two distinct colonization patterns. In conclusion, our study indicated differences in the oral microbiota in infants due to mode of delivery, with vaginally delivered infants having a higher number of taxa detected by the HOMIM microarray.
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| 5. |
- Michaud, Dominique S., et al.
(författare)
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Lifestyle, dietary factors, and antibody levels to oral bacteria in cancer-free participants of a European cohort study
- 2013
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Ingår i: Cancer Causes and Control. - : Springer Netherlands. - 0957-5243 .- 1573-7225. ; 24:11, s. 1901-1909
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Increasing evidence suggests that oral microbiota play a pivotal role in chronic diseases, in addition to the well-established role in periodontal disease. Moreover, recent studies suggest that oral bacteria may also be involved in carcinogenesis; periodontal disease has been linked to several cancers. In this study, we examined whether lifestyle factors have an impact on antibody levels to oral bacteria.METHODS: Data on demographic characteristics, lifestyle factors, and medical conditions were obtained at the time of blood sample collection. For the current analysis, we measured antibody levels to 25 oral bacteria in 395 cancer-free individuals using an immunoblot array. Combined total immunoglobin G (IgG) levels were obtained by summing concentrations for all oral bacteria measured.RESULTS: IgG antibody levels were substantially lower among current and former smokers (1,697 and 1,677 ng/mL, respectively) than never smokers (1,960 ng/mL; p trend = 0.01), but did not vary by other factors, including body mass index, diabetes, physical activity, or by dietary factors, after adjusting for age, sex, education, country, and smoking status. The highest levels of total IgG were found among individuals with low education (2,419 ng/mL).CONCLUSIONS: Our findings on smoking are consistent with previous studies and support the notion that smokers have a compromised humoral immune response. Moreover, other major factors known to be associated with inflammatory markers, including obesity, were not associated with antibody levels to a large number of oral bacteria.
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| 6. |
- Tanner, A. C. R., et al.
(författare)
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White-spot Lesions and Gingivitis Microbiotas in Orthodontic Patients
- 2012
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Ingår i: Journal of Dental Research. - : SAGE Publications. - 0022-0345 .- 1544-0591. ; 91:9, s. 853-858
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Tidskriftsartikel (refereegranskat)abstract
- White-spot lesions (WSL) associated with orthodontic appliances are a cosmetic problem and increase risk for cavities. We characterized the microbiota of WSL, accounting for confounding due to gingivitis. Participants were 60 children with fixed appliances, aged between 10 and 19 yrs, half with WSL. Plaque samples were assayed by a 16S rRNA-based microarray (HOMIM) and by PCR. Mean gingival index was positively associated with WSL (p = 0.018). Taxa associated with WSL by microarray included Granulicatella elegans (p = 0.01), Veillonellaceae sp. HOT 155 (p < 0.01), and Bifidobacterium Cluster 1 (p = 0.11), and by qPCR, Streptococcus mutans (p = 0.008) and Scardovia wiggsiae (p = 0.04) Taxa associated with gingivitis by microarray included: Gemella sanguinis (p = 0.002), Actinomyces sp. HOT 448 (p = 0.003), Prevotella cluster IV (p = 0.021), and Streptococcus sp. HOT 071/070 (p = 0.023); and levels of S. mutans (p = 0.02) and Bifidobacteriaceae (p = 0.012) by qPCR. Species' associations with WSL were minimally changed with adjustment for gingivitis level. Partial least-squares discriminant analysis yielded good discrimination between children with and those without WSL. Granulicatella, Veillonellaceae and Bifidobacteriaceae, in addition to S. mutans and S. wiggsiae, were associated with the presence of WSL in adolescents undergoing orthodontic treatment. Many taxa showed a stronger association with gingivitis than with WSL.
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| 7. |
- Tanner, ACR, et al.
(författare)
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Microbiota of severe early childhood caries before and after therapy
- 2011
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Ingår i: Journal of Dental Research. - Washington, D.C. : American dental association. - 0022-0345 .- 1544-0591. ; 90:11, s. 1298-1305
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Tidskriftsartikel (refereegranskat)abstract
- Severe early childhood caries (ECC) is difficult to treat successfully. This study aimed to characterize the microbiota of severe ECC and evaluate whether baseline or follow-up microbiotas are associated with new lesions post-treatment. Plaque samples from 2- to 6-year-old children were analyzed by a 16S rRNA-based microarray and by PCR for selected taxa. Severe-ECC children were monitored for 12 months post-therapy. By microarray, species associated with severe-ECC (n = 53) compared with caries-free (n = 32) children included Slackia exigua (p = 0.002), Streptococcus parasanguinis (p = 0.013), and Prevotella species (p < 0.02). By PCR, severe-ECC-associated taxa included Bifidobacteriaceae (p < 0.001), Scardovia wiggsiae (p = 0.003), Streptococcus mutans with bifidobacteria (p < 0.001), and S. mutans with S. wiggsiae (p = 0.001). In follow-up, children without new lesions (n = 36) showed lower detection of taxa including S. mutans, changes not observed in children with follow-up lesions (n = 17). Partial least-squares modeling separated the children into caries-free and two severe-ECC groups with either a stronger bacterial or a stronger dietary component. We conclude that several species, including S. wiggsiae and S. exigua, are associated with the ecology of advanced caries, that successful treatment is accompanied by a change in the microbiota, and that severe ECC is diverse, with influences from selected bacteria or from diet.
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| 8. |
- Vestman, Nelly Romani, et al.
(författare)
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Characterization and in vitro properties of oral lactobacilli in breastfed infants
- 2013
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Ingår i: BMC Microbiology. - : BioMed Central. - 1471-2180. ; 13, s. 193-
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Tidskriftsartikel (refereegranskat)abstract
- Background: Lactobacillus species can contribute positively to general and oral health and are frequently acquired by breastfeeding in infancy. The present study aimed to identify oral lactobacilli in breast and formula-fed 4 month-old infants and to evaluate potential probiotic properties of the dominant Lactobacillus species detected. Saliva and oral swab samples were collected from 133 infants who were enrolled in a longitudinal study (n=240) examining the effect of a new infant formula on child growth and development. Saliva was cultured and Lactobacillus isolates were identified from 16S rRNA gene sequences. Five L. gasseri isolates that differed in 16S rRNA sequence were tested for their ability to inhibit growth of selected oral bacteria and for adhesion to oral tissues. Oral swab samples were analyzed by qPCR for Lactobacillus gasseri.Results: 43 (32.3%) infants were breastfed and 90 (67.7%) were formula-fed with either a standard formula (43 out of 90) or formula supplemented with a milk fat globule membrane (MFGM) fraction (47 out of 90). Lactobacilli were cultured from saliva of 34.1% breastfed infants, but only in 4.7% of the standard and 9.3% of the MFGM supplemented formula-fed infants. L. gasseri was the most prevalent (88% of Lactobacillus positive infants) of six Lactobacillus species detected. L. gasseri isolates inhibited Streptococcus mutans binding to saliva-coated hydroxyapatite, and inhibited growth of S. mutans, Streptococcus sobrinus, Actinomyces naeslundii, Actinomyces oris, Candida albicans and Fusobacterium nucleatum in a concentration dependent fashion. L. gasseri isolates bound to parotid and submandibular saliva, salivary gp340 and MUC7, and purified MFGM, and adhered to epithelial cells. L. gasseri was detected by qPCR in 29.7% of the oral swabs. Breastfed infants had significantly higher mean DNA levels of L. gasseri (2.14 pg/uL) than infants fed the standard (0.363 pg/uL) or MFGM (0.697 pg/uL) formula.Conclusions: Lactobacilli colonized the oral cavity of breastfed infants significantly more frequently than formulafed infants. The dominant Lactobacillus was L. gasseri, which was detected at higher levels in breastfed than formula-fed infants and displayed probiotic traits in vitro.
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