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Azam Bakhshandeh Isabela Floriano Mariana Minatel Braga Kristine Arnholdt Thorlacius Kim Rud Ekstrand 《Acta odontologica Scandinavica》2018,76(7):509-514
Objectives: We aimed to determine the relation between the radiographical depth of approximal lesions and the presence of bacteria in the dentine in posterior teeth in both dentitions.Material and methods: Sample 1 consisted of 34 approximal lesions in primary molars in children aged 5–7 years old. Sample 2 consisted of 48 approximal lesions in molars and premolars in adult patients aged 18–67 years old. All lesions were in need of restorative treatment according to the dentists. During the operative interventions dentine biopsies were collected with a sterile bur just pulpally of the enamel–dentin junction. Two authors evaluated the presence/absence of bacterial colonies. The lesions depth on bitewing radiographs (RSCORING) were assessed independently by two examiners twice using the ICCMS classification system: RI=initial-; RM=moderate-; RE=extensive caries.Results: In sample 1, the RSCORING was distributed as follows: RI=15; RM=12; RE?=?7. In 9 cases the lesions were clinically cavitated. Bacteria were visible on the agar plates in one case (7%) of the RI lesion, 86% of the RM lesions and in all the RE lesions, (p?.001). In sample 2, RSCORING was distributed as follows RI=14; RM=23; RE=9. In 15 cases, the lesions were clinically cavitated. In 2 cases (14%), there were visible bacteria on the agar plates among the RI lesions, while this was the case in 86% of RM lesions and in 100% of RE lesions (p?.001).Conclusions: RM and RE lesions seem to harbor bacteria in the dentine and are candidates for invasive treatment. In contrast, RI lesions should in general be managed non-invasively. 相似文献
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Kouhkan A Pourpak Z Moin M Dorosty AR Safaralizadeh R Teimorian S Farhoudi A Aghamohammadi A Mesdaghi M Kazemnejad A 《Iranian journal of allergy, asthma, and immunology》2004,3(4):189-196
Nutrition is an important factor that influences immunity, and nutritional deficiencies can impair resistance to infections. Malnutrition is the most common cause of immunodeficiency worldwide. Trace elements such as zinc, selenium, iron, and copper can influence several components of immunity. Primary antibody deficiency disorders are a group of disorders characterized by an unusual susceptibility to infections and malnutrition. Impaired nutritional status has been reported in immunodeficient patients. The aim of this study was to determine anthropometric indices and trace elements status in these patients. Thirty-eight children (28 males, 10 females, aged 2-18 years) with primary antibody deficiency referring to Children's Medical Center of Tehran University of Medical Science were enrolled in this research. Primary immunodeficiency disorders consisting of CVID, XLA, IgA deficiency, IgG subclass deficiency, and hyper IgM were assessed. Anthropometric indices, comprised of height, weight that were measured and body mass index (BMI) was calculated. Height-for-age (HAZ), weight-for-height (WHZ) and weight-for-age (WAZ) were determined according to Z-score to study mild, moderate and severe malnutrition. Serum copper, zinc, selenium and iron levels were measured by an atomic absorption spectrometer. The most common disorders were CVID 52.5% and X-linked agammaglobulinaemia 27.5%. Based on BMI measurements 21.1% of patients had malnutrition. According to HAZ, 13.2%, 13.2% and 36.8% had severe, moderate and mild malnutrition, respectively. According to WAZ, 10.5%, 18.4% and 28.6% had severe, moderate and mild malnutrition, respectively. Regarding to WHZ, 14.3% and 28.6% had moderate and mild malnutrition, respectively. Low selenium levels and high copper levels were observed in 37.5% and 70.3%, respectively. Anthropometric data showed that the frequency of malnutrition in these patients was higher than the CDC standard. Low serum selenium levels and high serum copper levels were observed, suggesting further research is needed on these parameters. Most of the patients had serum zinc and iron levels within the normal range. It is recommeded that clinical immunologists and nutritionists should make a collective effort to provide these patients with standard or specialized diets so as to decrease the risk of infection. 相似文献
205.
Site-specific mutations in the mature form of human IL-18 with enhanced biological activity and decreased neutralization by IL-18 binding protein 总被引:5,自引:0,他引:5
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Kim SH Azam T Yoon DY Reznikov LL Novick D Rubinstein M Dinarello CA 《Proceedings of the National Academy of Sciences of the United States of America》2001,98(6):3304-3309
IL-18 can be considered a proinflammatory cytokine mediating disease as well as an immunostimulatory cytokine that is important for host defense against infection and cancer. The high-affinity, constitutively expressed, and circulating IL-18 binding protein (IL-18BP), which competes with cell surface receptors for IL-18 and neutralizes IL-18 activity, may act as a natural antiinflammatory as well as immunosuppressive molecule. In the present studies, the IL-18 precursor caspase-1 cleavage site was changed to a factor Xa site, and, after expression in Escherichia coli, mature IL-18 was generated by factor Xa cleavage. Mature IL-18 generated by factor Xa cleavage was fully active. Single point mutations in the mature IL-18 peptide were made, and the biological activities of the wild-type (WT) IL-18 were compared with those of the mutants. Mutants E42A and K89A exhibited 2-fold increased activity compared with WT IL-18. A double mutant, E42A plus K89A, exhibited 4-fold greater activity. Unexpectedly, IL-18BP failed to neutralize the double mutant E42A plus K89A compared with WT IL-18. The K89A mutant was intermediate in being neutralized by IL-18BP, whereas neutralization of the E42A mutant was comparable to that in the WT IL-18. The identification of E42 and K89 in the mature IL-18 peptide is consistent with previous modeling studies of IL-18 binding to IL-18BP and explains the unusually high affinity of IL-18BP for IL-18. 相似文献
206.
Lee JK Kim SH Lewis EC Azam T Reznikov LL Dinarello CA 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(23):8815-8820
IL-1 and IL-18 are members of the IL-1 family of ligands, and their receptors are members of the IL-1 receptor family. Although several biological properties overlap for these cytokines, differences exist. IL-18 uniquely induces IFN-gamma from T lymphocytes and natural killer cells but does not cause fever, whereas fever is a prominent characteristic of IL-1 in humans and animals. In the present study, human epithelial cells were stably transfected with the IL-18 receptor beta chain and responded to IL-18 with increased production of IL-1alpha, IL-6, and IL-8. Five minutes after exposure to either cytokine, phosphorylation of mitogen activated protein kinase (MAPK) p38 was present; specific inhibition of p38 MAPK reduced IL-18 activity to background levels. Whereas IL-1beta induced the expression of the NF-kappaB-reporter gene and was suppressed by competitive inhibition of NF-kappaB binding, IL-18 responses were weak or absent. In contrast to IL-1beta, IL-18 also did not activate degradation of the NF-kappaB inhibitor. After 4 h, both cytokines induced comparable levels of mRNA for the chemokine IL-8 but, in the same cells, steady-state levels of cyclooxygenase (COX)-2 mRNA were high after IL-1beta but low or absent after IL-18. After 30 h, IL-18-induced COX-2 appeared in part to be IL-1 dependent. Similarly, low levels of prostaglandin E2 were measured in IL-18-stimulated A549 cells and freshly obtained primary human monocytes and mouse macrophages. We conclude that in epithelial cells, IL-18 signal transduction is primarily via the MAPK p38 pathway rather than NF-kappaB, which may explain the absence of COX-2 and the failure of IL-18 to cause fever. 相似文献
207.
The percutaneous closure of atrial septal defects is increasingly used. Serious complications of the procedure, such as cardiac perforation and tamponade, are rare and usually occur <72 hours after device placement. The investigators report the late development of the erosion of an Amplatzer septal occluder into the ascending aorta with associated aortic-to-right atrial fistula formation. 相似文献
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Hemodynamic effects of anesthetic induction in patients treated with beta and calcium channel blockers 总被引:1,自引:0,他引:1
BACKGROUND: The response to anesthetic induction and airway manipulation in the presence of cardiovascular disease and antihypertensive therapy has not been adequately investigated. METHODS: The blood pressure, pulse pressure and heart rate changes at induction and following tracheal intubation were compared in patients who were on either preoperative beta-adrenergic blocker therapy (BB group, n = 20) or a combination of beta-adrenergic blocker and calcium channel blocker therapy (BB + CCB group, n = 20). A standardized anesthesia induction protocol was followed, in the two gourps. RESULTS: No statistical difference was observed in the hemodynamic parameters between the two groups. The total number of hypotensive patients (SAP 90 相似文献