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61.
Dahlén G Charalampakis G Abrahamsson I Bengtsson L Falsen E 《Journal of periodontal research》2012,47(3):354-364
Dahlén G, Charalampakis G, Abrahamsson I, Bengtsson L, Falsen E. Predominant bacterial species in subgingival plaque in dogs. J Periodont Res 2012; 47: 354–364. © 2011 John Wiley & Sons A/S Background and Objective: The dog has been used extensively for experimental and microbiological studies on periodontitis and peri‐implantitis without detailed knowledge about the predominant flora of the subgingival plaque. This study was designed to evaluate the predominant cultivable bacterial species in dogs and compare them phenotypically and genotypically with corresponding human species. Material and Methods: Four subgingival samples were taken from two upper premolars in each of six Labrador retrievers. The samples from each dog were processed for anaerobic culture. From the samples of each dog, the five or six predominating bacteria based on colony morphology were selected and pure cultured. Each of the strains was characterized by Gram stain, anaerobic/aerobic growth and API‐ZYM test. Eighteen strains showing clear‐cut phenotypic differences were further classified based on DNA sequencing technology. Cross‐reactions of DNA probes from human and dog strains were also tested against a panel of both human and dog bacterial species. Results: Thirty‐one strains in the dogs were isolated and characterized. They represented 21 different species, of which six belonged to the genus Porphyromonas. No species was found consistently in the predominant flora of all six dogs. Porphyromonas crevioricanis and Fusobacterium canifelinum were the two most prevalent species in predominant flora in dogs. DNA probes from human and dog species cross‐reacted to some extent with related strains from humans and dogs; however, distinct exceptions were found. Conclusion: The predominant cultural subgingival flora in dogs shows great similarities with the subgingival bacteria from humans at the genus level, but distinct differences at the species level; however, a genetic relatedness could be disclosed for most strains investigated. 相似文献
62.
Ketamine and xylazine depress sensory-evoked parallel fiber and climbing fiber responses 总被引:1,自引:0,他引:1
The last few years have seen an increase in the variety of in vivo experiments used for studying cerebellar physiological mechanisms. A combination of ketamine and xylazine has become a particularly popular form of anesthesia. However, because nonanesthetized control conditions are lacking in these experiments, so far there has been no evaluation of the effects of these drugs on the physiological activity in the cerebellar neuronal network. In the present study, we used the mossy fiber, parallel fiber, and climbing fiber field potentials evoked in the nonanesthetized, decerebrated rat to serve as a control condition against which the effects of intravenous drug injections could be compared. All anesthetics were applied at doses required for normal maintenance of anesthesia. We found that ketamine substantially depressed the evoked N3 field potential, which is an indicator of the activity in the parallel fiber synapses (-40%), and nearly completely abolished evoked climbing fiber field potentials (-90%). Xylazine severely depressed the N3 field (-75%) and completely abolished the climbing fiber field (-100%). In a combination commonly used for general anesthesia (20:1), ketamine-xylazine injections also severely depressed the N3 field (-75%) and nearly completely abolished the climbing fiber field (-90%). We also observed that lowered body and surface temperatures (<34 degrees C) resulted in a substantial depression of the N3 field (-50%). These results urge for some caution in the interpretations of studies on cerebellar network physiology performed in animals anesthetized with these drugs. 相似文献
63.
Bäckman B Grevér-Sjölander AC Bengtsson K Persson J Johansson I 《International journal of paediatric dentistry / the British Paedodontic Society [and] the International Association of Dentistry for Children》2007,17(1):19-28
OBJECTIVE: The aim of this study was to describe the number of erupted teeth, sucking habits, tongue morphology, facial expression and speech in children with Down syndrome (DS) aged 48 +/- 6 months and treated from 6 months of age with palatal plates in combination with speech and language therapy. METHODS: The research took the form of a multicentre, multidisciplinary, longitudinal study of children with DS followed from the age of 6 months. A total of 37 children with DS were included. One child could not cooperate at all and was excluded from the evaluations. In combination with speech and language intervention provided by speech and language therapists, the children used palatal plates provided by dentists from 6 months of age. In the evaluation, the children in the sample (n = 36) were compared with two similarly aged control groups: one group of children with DS who never had used palatal plates (n = 31) and one group of children with normal development (n = 36). The evaluation of oral parameters was performed by dentists after calibration. Registration of facial expression and speech was done by a speech and language therapist, and the evaluation was done by two speech and language therapists and one phonetician who were calibrated in joint discussions. RESULTS: In contrast to the children with DS in the control group, the subjects in the study were found to have as many erupted teeth as the children with normal development. The prevalence of sucking habits did not differ between the three groups. Only children with DS sucked their tongue, a toy or other things in addition to a thumb or dummy. The prevalence of tongue diastase in the study group with DS was of the same magnitude as in the evaluation at the age of 18 +/- 3 months. The palatal plates were used by 57-65% of the children without any larger problems. In the study sample, the possible beneficial effects of palatal plate therapy were a lower prevalence of posterior cross-bite, a higher prevalence of frontal cusp-to-cusp relation and a lower prevalence of frontal open bite. Evaluation of facial expression and speech showed a higher score for facial expression and a better communicative capacity in the children in the study group than in the control children with DS. CONCLUSIONS: In children with DS, palatal plate therapy between 6 and 48 months of age in connection with speech and language intervention had a positive effect on occlusion, oral motor function, facial expression and speech. No harmful effects were observed. Although this is a valuable method, however, it must be emphasized that palatal plate therapy puts additional demands on already burdened children and their caretakers. 相似文献
64.
65.
To assess the relative roles and potential contribution of adrenergic receptor subtypes other than the beta3-adrenergic receptor in norepinephrine-mediated glucose uptake in brown adipocytes, we have here analyzed adrenergic activation of glucose uptake in primary cultures of brown adipocytes from wild-type and beta3-adrenergic receptor knockout (KO) mice. In control cells in addition to high levels of beta3-adrenergic receptor mRNA, there were relatively low alpha1A-, alpha1D-, and moderate beta1-adrenergic receptor mRNA levels with no apparent expression of other adrenergic receptors. The levels of alpha1A-, alpha1D-, and beta1-adrenergic receptor mRNA were not changed in the beta3-KO brown adipocytes, indicating that the beta3-adrenergic receptor ablation does not influence adrenergic gene expression in brown adipocytes in culture. As expected, the beta3-adrenergic receptor agonists BRL-37344 and CL-316 243 did not induce 2-deoxy-d-glucose uptake in beta3-KO brown adipocytes. Surprisingly, the endogenous adrenergic neurotransmitter norepinephrine induced the same concentration-dependent 2-deoxy-D-glucose uptake in wild-type and beta3-KO brown adipocytes. This study demonstrates that beta1-adrenergic receptors, and to a smaller degree alpha1-adrenergic receptors, functionally compensate for the lack of beta3-adrenergic receptors in glucose uptake. Beta1-adrenergic receptors activate glucose uptake through a cAMP/protein kinase A/phosphatidylinositol 3-kinase pathway, stimulating conventional and novel protein kinase Cs. The alpha1-adrenergic receptor component (that is not evident in wild-type cells) stimulates glucose uptake through a phosphatidylinositol 3-kinase and protein kinase C pathway in the beta3-KO cells. 相似文献
66.
Double blind, placebo controlled food reactions do not correlate to IgE allergy in the diagnosis of staple food related gastrointestinal symptoms. 总被引:4,自引:0,他引:4
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BACKGROUND: The mechanisms for adverse reactions to foods in the gastrointestinal tract are poorly understood. There is conflicting evidence in the literature on the role for IgE mediated allergy in gastrointestinal reactions to staple foods. AIM: The aim was therefore to study the role of IgE mediated allergy in a group of patients with a history of gastrointestinal symptoms related to staple foods (cows' milk, hens' egg, wheat and rye flour) verified in double blind placebo controlled challenges (DBPCFC). PATIENTS: Fifteen patients with DBPCFC, identified by screening of 96 consecutive patients referred to our allergy clinic for investigation of suspected gastrointestinal symptoms due to staple foods. METHODS: The screening included diaries as well as elimination diets and open and blinded food challenges. The frequency of atopy were compared between the double blind positive and double blind negative patients. RESULTS: The positive DBPCFC in the 15 patients included eight patients with milk intolerance, four with wheat flour, two with egg, and one with rye flour. There was no indications of an allergic pathogenesis in all 15 patients with positive DBPCFC, as the skin prick test and radioallergosorbent test were negative for the relevant allergens. The frequency of atopy was four of 21 (19%) in the double blind negative group and three of 15 (20%) in the double blind positive group. CONCLUSION: In adult patients with staple food induced gastrointestinal symptoms, objectively verified by DBPCFC, there were no indications of IgE mediated allergy to the relevant foods suggesting other mechanisms in adults than in children. Future studies may include measures of local events in the shock organs in relation to food intake, for instance utilising inflammatory markers in jejunal fluids. 相似文献
67.
68.
17beta-estradiol (E2) modulates cytokine and chemokine expression in human monocyte-derived dendritic cells 总被引:4,自引:0,他引:4
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The effects of estrogen on the immune system are still largely unknown. We have investigated the effect of 17beta-estradiol (E(2)) on human monocyte-derived immature dendritic cells (iDCs). Short-term culture in E(2) had no effect on iDC survival or the expression of cell surface markers. However, E(2) treatment significantly increased the secretion of interleukin 6 (IL-6) in iDCs and also increased secretion of osteoprotegerin (OPG) by DCs. Furthermore, E(2) significantly increased secretion of the inflammatory chemokines IL-8 and monocyte chemoattractant protein 1 (MCP-1) by iDCs, but not the production of the constitutive chemokines thymus and activation-regulated chemokine (TARC) and macrophage-derived chemokine (MDC). However, after E(2) pretreatment the lipopolysaccharide (LPS)-induced production of MCP-1, TARC, and MDC by DCs was clearly enhanced. Moreover, mature DCs pretreated with E(2) stimulated T cells better than control cells. Finally, we found that E(2) provides an essential signal for migration of mature DCs toward CCL19/macrophage inflammatory protein 3beta (MIP3beta). In summary, E(2) may affect DC regulation of T-cell and B-cell responses, as well as help to sustain inflammatory responses. This may explain, in part, the reason serum levels of estrogen correlate with the severity of certain autoimmune diseases. 相似文献
69.
Tomas Hansson Wenche Hansen Ulla Tjärnlund Lennart Balk Bengt-Erik Bengtsson 《Archives of environmental contamination and toxicology》2014,66(2):237-247
Since the new millennium, a notion has developed in certain parts of society that environmental pollutants and their associated effects are under control. The primary objective of this investigation, performed in 2003, was to test whether this was actually the case in an industrialised region in the County of Västernorrland in northern Sweden with well-documented environmental pollution from past and present activities. This was performed by measuring a moderate battery of simple biomarkers in adult female perch at several stations. The point sources included sewage-treatment plants, pulp and paper mills, as well as other industries. The biomarkers included growth, somatic indices, gonad maturation status, gonad pigmentation, fin erosion, skin ulcers, and ethoxyresorufin-O-deethylase (EROD) activity in the liver. The results showed that the environmental pollutants and their associated effects were not under control. In fact, the health of the perch was impaired at all of the polluted stations. Many responses were unspecific with respect to underlying cause, whereas some effects on EROD activity and gonad maturation status were attributed to historical creosote pollution and current kraft pulp mill effluents, respectively. The data presented may also be used as reference values for future investigations of health effects in perch. 相似文献
70.
Kieran F. Docherty Pardeep S. Jhund Olof Bengtsson David L. DeMets Silvio E. Inzucchi Lars Kber Mikhail N. Kosiborod Anna Maria Langkilde Felipe A. Martinez Marc S. Sabatine Mikaela Sjstrand Scott D. Solomon John J.V. McMurray 《Diabetes care》2020,43(11):2878
OBJECTIVETo determine whether the benefits of dapagliflozin in patients with heart failure and reduced ejection fraction (HFrEF) and type 2 diabetes in the Dapagliflozin And Prevention of Adverse-Outcomes in Heart Failure trial (DAPA-HF) varied by background glucose-lowering therapy (GLT).RESEARCH DESIGN AND METHODSWe examined the effect of study treatment by the use or not of GLT and by GLT classes and combinations. The primary outcome was a composite of worsening heart failure (hospitalization or urgent visit requiring intravenous therapy) or cardiovascular death.RESULTSIn the 2,139 type 2 diabetes patients, the effect of dapagliflozin on the primary outcome was consistent by GLT use or no use (hazard ratio 0.72 [95% CI 0.58–0.88] vs. 0.86 [0.60–1.23]; interaction P = 0.39) and across GLT classes.CONCLUSIONSIn DAPA-HF, dapagliflozin improved outcomes irrespective of use or no use of GLT or by GLT type used in patients with type 2 diabetes and HFrEF. 相似文献