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891.
Although separate prediction models for donors and recipients were previously published, we identified a need to predict outcomes of donor/recipient simultaneously, as they are clearly not independent of each other. We used characteristics from transplantations performed at the Oslo University Hospital from 1854 live donors and from 837 recipients of a live donor kidney transplant to derive Cox models for predicting donor mortality up to 20 years, and recipient death, and graft loss up to 10 years. The models were developed using the multivariable fractional polynomials algorithm optimizing Akaike’s information criterion, and optimism-corrected performance was assessed. Age, year of donation, smoking status, cholesterol and creatinine were selected to predict donor mortality (C-statistic of 0.81). Linear predictors for donor mortality served as summary of donor prognosis in recipient models. Age, sex, year of transplantation, dialysis vintage, primary renal disease, cerebrovascular disease, peripheral vascular disease and HLA mismatch were selected to predict recipient mortality (C-statistic of 0.77). Age, dialysis vintage, linear predictor of donor mortality, HLA mismatch, peripheral vascular disease and heart disease were selected to predict graft loss (C-statistic of 0.66). Our prediction models inform decision-making at the time of transplant counselling and are implemented as online calculators.  相似文献   
892.
Purpose:This study assessed the regeneration potential of mesenchymal stem cells (MSC) from adipose tissue associated with platelet-rich plasma (PRP) in bone regeneration.Methods:Thirty Wistar rats (Rattus norvegicus albinos) were divided into five groups (according to the grafting material and time to euthanasia): (1) autograft - 14 days (control), (2) autograft - 28 days (control), (3) MSC + PRP - 14 days, (4) MSC + PRP + papaverine - 14 days and (5) MSC + PRP + papaverine - 28 days. After euthanasia, the graft was removed and histological slides were prepared. They were assessed by a blinded pathologist using a previously published histological scale as parameter.Results:There was some degree of neoformed bone trabeculae (NBT) in 93.3% of the samples, as well as osteoblastic activity (OA). The autograft groups (14 and 28 days) had higher levels in the formation of bone trabeculae. Nonparametric data were analyzed using the Wilcoxon-Mann-Whitney test and proved not to be statistically significant at p < 0.05.Conclusions:Experimental parietal bone reconstruction, combining MSC, PRP and papaverine presented regeneration in all groups with no significant difference among them.Key words: Bone Regeneration, Platelet-Rich Plasma, Tissue Engineering, Rats  相似文献   
893.
The prevalence of obesity is increasing globally. There is evidence that the uncontrolled energetic metabolism in obese patients can accelerate periodontal disease. Therefore, the aim of this study was evaluate the possible relationship between hypothalamic obesity induced by neonatal treatment with MSG and experimental periodontal disease. Newborn male Wistar rats received subcutaneous injections in the cervical region, of 4g/Kg/day of body weight (BW) of MSG (MSG group) or hypertonic saline solution, 1.25/kg/day BW (control group, CTL). At 70 days of life periodontal disease was induced in these animals. After they were sacrificed, radiographic analyses of alveolar bone resorption and Tumor Necrosis Factor α (TNFα) gene expression in gingival tissue were performed. The neonatal treatment with MSG did not affect the concentration of plasma glucose and cholesterol (CHOL). However, plasma insulin, non-esterified fatty acids (NEFA) and triglycerides (TG) leves were higher in MSG compared with CTL group. The alveolar bone resorption was 44% lower in MSG-obese rats compared with CTL rats. In the presence of periodontal ligature, there was an increase in this parameter in all groups. The TNFα gene expression, an inflammatory marker, in periodontal tissue was similar in obese and CTL rats. The presence of ligature increased TNFα gene expression in both groups, but in a lower extension in MSG-obese rats. In conclusion these results suggested that hypothalamic obesity may produce a protective effect against periodontal disease, however further research is needed to understand the mechanisms involved in this process.  相似文献   
894.
Objective: A study is made of the clinical course of patients with episodic cluster headache following the injection of corticosteroids in the proximity of the sphenopalatine ganglion of the affected side. Study Design: A retrospective observation study was made corresponding to the period between 2006 and 2010. Patients with episodic cluster headache received corticosteroid infiltrations in the vicinity of the sphenopalatine ganglion. Data were collected to assess the clinical course, quantifying pain intensity and quality of life. A total of 23 patients (11 women and 12 men) with a mean age of 50.4 years (range 25-65) were included. Forty percent of the patients had undergone dental extractions in the quadrant affected by the pain, before the development of episodic cluster headache, and 37.8% underwent extractions in the same quadrant after appearance of the headache. Results: Most of the patients suffered 1-3 attacks a day, with a duration of pain of between 31-90 minutes. The mean pain intensity score during the attacks at the time of the first visit was 8.8 (range 6-10), versus 5.4 (range 3-9) one week after the first corticosteroid injection. On the first visit, 86.9% of the patients reported unbearable pain, versus 21.7% after one week, and a single patient after one month. Conclusions: The evolution of episodic cluster headache is unpredictable and variable, though corticosteroid administration clearly reduces the attacks and their duration. Key words:Episodic cluster headache, vascular pain, sphenopalatine ganglion, corticosteroid infiltration.  相似文献   
895.
The esthetic treatment of darkened anterior teeth represents a great challenge to dentists, because dental materials ideally should match the natural teeth. The optical behavior of the final restoration is determined by the color of the underlying tooth structure, the color of the luting agent, and the thickness and opacity of the ceramic material used. This article reports a case in which veneers and full crowns made of heat-pressed, lithium disilicate glass-ceramic were used for the esthetic rehabilitation of anterior discolored teeth. The patient was referred for treatment with defective anterior composite resin restorations, provisional acrylic resin crowns, darkening of the gingival margins, and uneven gingival contours. The multidisciplinary treatment plan included dental bleaching, periodontal plastic surgery to create gingival symmetry, and indirect all-ceramic restorations using high-opacity lithium disilicate glass-ceramic ingots. The treatment was successful and an excellent esthetic result was achieved.  相似文献   
896.
This study investigated the prevalence of dental caries and periodontal condition in a population with sickle cell disease (SCD), analyzing some associations with disease severity. The Decayed, Missing and Filled Teeth index (DMFT) and Community Periodontal Index (CPI) were recorded for 99 individuals with SCD and 91 matched controls. Socio-demographic status, oral health behaviors, and history of clinical severity of SCD were assessed. Statistical comparisons were performed between the group with SCD and the control group, as well as multivariate logistic regression analyses with DMFT index and CPI as the dependent variables. The mean number of decayed teeth was significantly higher in individuals with HbSS. Older age, female gender, and daily smoking were identified as risk factors for higher DMFT, while older age and absence of daily use of dental floss were risk factors for the development of periodontal disease. In conclusion, risk factors known to cause caries and periodontal disease had more influence on oral health than the direct impact of SCD.  相似文献   
897.
BackgroundIdentifying changes in the oral health status of older populations, and their predictors and explanations, is necessary for public health planning. The authors assessed patterns of change in oral health–related quality of life in a large cohort of older adults in Brazil during a five-year period and evaluated associations between baseline characteristics and those changes.MethodsThe sample consisted of 747 older people enrolled in a Brazilian cohort study called the Health, Well-Being and Aging (Saúde, Bem-estar e Envelhecimento [SABE]) Study. Trained examiners measured participants' self-perceived oral health by using the General Oral Health Assessment Index (GOHAI). The authors calculated changes in the overall GOHAI score and in the scores for each of the GOHAI's three dimensions individually by subtracting the baseline score from the score at follow-up. A positive difference indicated improvement in oral health, a negative difference indicated a decline and a difference of zero indicated no change.ResultsThe authors found that 48.56 percent of the participants experienced a decline in oral health and 33.48 percent experienced an improvement. Participants with 16 or more missing teeth and eight or more years of education were more likely to have an improvement in total GOHAI score. Deterioration was more likely to occur among those with two or more diseases. Improvement and decline in GOHAI functional scores were related to the number of missing teeth. The authors found no significant model for the change in the psychosocial score, and self-rated general health was the only variable related to both improvement and decline in pain or discomfort scores.ConclusionsThe authors observed a bidirectional change in self-perceived oral health, with deterioration predominating. The strongest predictor of improvement in the total GOHAI score was the number of missing teeth, whereas the number of diseases was the strongest predictor of deterioration.Clinical ImplicationsDental professionals and policymakers need to know the directions of change in older adults' oral health to establish treatment priorities and evaluate the impact of services directed at this population.  相似文献   
898.
The aim of this study was to determine the effect of the oral environment on the corrosion of dental alloys with different compositions, using electrochemical methods. The corrosion rates were obtained from the current-potential curves and electrochemical impedance spectroscopy (EIS). The effect of artificial saliva on the corrosion of dental alloys was dependent on alloy composition. Dissolution of the ions occurred in all tested dental alloys and the results were strongly dependent on the general alloy composition. Regarding the alloys containing nickel, the Ni-Cr and Ni-Cr-Ti alloys released 0.62 mg/L of Ni on average, while the Co-Cr dental alloy released ions between 0.01 and 0.03 mg/L of Co and Cr, respectively.The open-circuit potential stabilized at a higher level with lower deviation (standard deviation: Ni-Cr-6Ti = 32 mV/SCE and Co-Cr = 54 mV/SCE). The potenciodynamic curves of the dental alloys showed that the Ni-based dental alloy with >70 wt% of Ni had a similar curve and the Co-Cr dental alloy showed a low current density and hence a high resistance to corrosion compared with the Ni-based dental alloys. Some changes in microstructure were observed and this fact influenced the corrosion behavior for the alloys. The lower corrosion resistance also led to greater release of nickel ions to the medium. The quantity of Co ions released from the Co-Cr-Mo alloy was relatively small in the solutions. In addition, the quantity of Cr ions released into the artificial saliva from the Co-Cr alloy was lower than Cr release from the Ni-based dental alloys.  相似文献   
899.
900.
Phagocytosis by neutrophils and monocytes constitutes the main defense mechanism against bacterial challenges in periodontitis. Phagocytosis by neutrophils has already been evaluated, whereas phagocytic function of monocytes has hardly been addressed so far.

Objectives

The aim of this study was to assess phagocytosis by neutrophils and monocytes in periodontitis.

Material and Methods

The sample included 30 subjects with severe periodontitis and 27 control subjects without periodontal disease. The phagocytic index (PhI) was calculated as the mean number of adhered/ingested Saccharomyces cerevisiae per phagocytozing monocyte or neutrophil multiplied by the percentage of phagocytes involved in phagocytosis.

Results

A significant reduction in phagocyte functions was observed in individuals with periodontitis. The median of PhI of neutrophils using non-sensitized S. cerevisiae was 3 for the control group, and 1.5 for the periodontitis group (p=0.01, Mann-Whitney test). The median of PhI of monocytes with non-sensitized S. cerevisiae was 26.13 for the control group, and 13.23 for the periodontitis group (p=0.03, Mann Whitney test). The median of PhI of monocytes assessed with sensitized S. cerevisiae was 97.92 for the control group and 60.1 for the periodontitis group (p=0.005, t-test).

Conclusion

The data demonstrated a reduction in the function of phagocytes, suggesting a decrease in immune defenses in periodontitis.  相似文献   
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