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11.
We evaluated the influence of allelic frequency of the human leukocyte antigen (HLA) -DRB1 on the acquisition of antibody response against malaria sporozoite and merozoite peptides in patients with Plasmodium vivax malaria acquired in endemic areas of Brazil. IgG antibodies were detected by enzyme-linked immunosorbent assay against four peptides of circumsporozoite protein (CSP) (amino, carboxyl, and VK210 and VK247 repeats) and peptides of merozoite surface protein 1 (MSP-1), apical membrane antigen 1 (AMA-1), and Duffy-binding protein (DBP). We found an association between HLA-DR3 and HLA-DR5 alleles and lack of antibody response to CSP amino terminal, as well as an association between HLA-DR3 and the highest antibody response to MSP1 (Pv200L). In conclusion, we suggest a potential regulatory role of the HLA-DRB1 alleles in the production of antibodies to a conserved region of P. vivax CSP and MSP1 in Brazilian population exposed to malaria.  相似文献   
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Objective:

The aim of this study was to evaluate the antimicrobial activity of auxiliary chemical substances and natural extracts on Candida albicans and Enterococcus faecalis inoculated in root canals.

Material and Methods:

Seventy-two human tooth roots were contaminated with C. albicans and E. faecalis for 21 days. The groups were divided according to the auxiliary chemical substance into: G1) 2.5% sodium hypochlorite (NaOCl), G2) 2% chlorhexidine gel (CHX), G3) castor oil, G4) glycolic Aloe vera extract, G5) glycolic ginger extract, and G6) sterile saline (control). The samples of the root canal were collected at different intervals: confirmation collection, at 21 days after contamination; 1st collection, after instrumentation; and 2nd collection, seven days after instrumentation. Microbiological samples were grown in culture medium and incubated at 37º C for 48 hours.

Results:

The results were submitted to the Kruskal-Wallis and Dunn (5%) statistical tests. NaOCl and CHX completely eliminated the microorganisms of the root canals. Castor oil and ginger significantly reduced the number of CFU of the tested bacteria. Reduction of CFU/mL at the 1st and 2nd collections for groups G1, G2, G3 and G4 was greater in comparison to groups G5 and G6.

Conclusion:

It was concluded that 2.5% sodium hypochlorite and 2% chlorhexidine gel were more effective in eliminating C. albicans and E. faecalis, followed by the castor oil and glycolic ginger extract. The Aloe vera extract showed no antimicrobial activity.  相似文献   
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Purpose

Untreated dental caries is a persistent oral problem among preschool children. Although there is vast evidence regarding the impact of dental caries on oral health-related quality of life (OHRQoL) in this age group, evidence on the impact of untreated caries severity is scarce. The purpose of this study was to investigate the impact of untreated caries severity on the OHRQoL of preschool children and their families.

Methods

A cross-sectional study was conducted with 563 individuals in the city of Goiania, Brazil. Data were collected through interviews with parents/caregivers and clinical examinations of their children. The OHRQoL was measured by the Brazilian version of the Early Childhood Oral Health Impact Scale. Untreated dental caries severity was assessed using validated indices. Other independent variables were socioeconomic, toothache prevalence, and the questionnaire respondent. Statistical analysis involved bivariate comparisons and Poisson regression analyses.

Results

A higher prevalence of impact on OHRQoL was found among preschool children with untreated dental caries with clinical consequences (PR 1.31; 95% CI 1.01–1.70) compared to those without caries; those aged 5 years (PR 1.47; 95% CI 1.18–1.82), compared to those aged two; and those with a toothache (PR 1.54; 95% CI 1.34–1.76), compared to those without toothache. Moreover, fathers (PR 0.71; 95% CI 0.55–0.92) and other respondents (PR 0.70; 95% CI 0.52–0.96) perceived less impact on the OHRQoL in comparison to mothers.

Conclusions

Severe untreated dental caries with clinical consequences had a negative impact on the children’s OHRQoL, regardless of toothache and socioeconomic factors.
  相似文献   
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The purpose of this retrospective study was to associate the amount of keratinized gingiva present in adolescents prior to orthodontic treatment to the development of gingival recessions after the end of treatment. The sample consisted of the intra-oral photographs and orthodontic study models from 209 Caucasian patients with a mean age of 11.20 +/- 1.83 years on their initial records and 14.7 +/- 1.8 years on their final records. Patients were either Angle Class I or II and were submitted to non-extraction orthodontic treatment. Gingival recession was evaluated by visual inspection of the lower incisors and canines as seen in the initial and final study models and intra-oral photographs. The amount of recession was quantified using a digital caliper and the observed post-treatment gingival margin alterations were classified as unaltered, coronal migration of the gingival margin or apical migration of the gingival margin. The width of the keratinized gingiva was measured from the mucogingival line to the gingival margin on the pre-treatment photographs. The teeth that developed gingival recession and those that did not have their gingival margin position changed did not differ in relation to the initial amount of keratinized gingiva (3.00 +/- 0.61 and 3.5 +/- 0.86 mm, respectively). Paradoxically, teeth that presented a coronal migration of the gingival margin had a smaller initial amount of keratinized gingiva (2.26 +/- 0.31 mm). The mean amount of initial keratinized gingiva did not predispose lower incisors and canines to gingival recession.  相似文献   
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Statistical shape modeling was employed to assess three-dimensional (3D) bony morphology between distal femurs and proximal tibiae of anterior cruciate ligament (ACL) injured knees, the contralateral uninjured knees of ACL injured subjects, and knees with no history of injury. Surface models were created by segmenting bone from bilateral computed-tomography scans of 20 subjects of their ACL injured knees and non-injured contralateral knees, and 20 knees of control subjects with no history of a knee injury. Correspondence particles were placed on each surface, and a principal component analysis determined modes of variation in the positions of the correspondence particles describing anatomical variation. ANOVAs assessed the statistical differences of 3D bony morphological features with main effects of injury state and sex. ACL injured knees were determined to have a more lateral femoral mechanical axis and a greater angle between the long axis and condylar axis of the femur. A smaller anterior–posterior dimension of the lateral tibial plateau was also associated with ACL injured knees. Results of this study demonstrate that there are more bony morphological features predisposing individuals for ACL injury than previously established. These bony morphological parameters may cause greater internal and valgus torques increasing stresses in the ACL. No differences were determined between the ACL injured knees and their uninjured contralateral knees demonstrating that knees of ACL injured individuals are at similar risk for injury. Further understanding of the effect of bony morphology on the risk for ACL injury could improve individualized ACL injury treatment and prevention.  相似文献   
20.
Although previous evidence suggests advantages of nifedipine over terbutaline as tocolytic agents, in some jurisdictions, terbutaline is approved for use and nifedipine is not. In women in preterm labour, we compared the impact of terbutaline versus nifedipine on inhibition of uterine contractions, preterm birth, neonatal sepsis, intracranial haemorrhage or necrotizing enterocolitis, death or admission to a neonatal intensive care unit and maternal adverse reactions. We randomized 32 women to nifedipine and 34 to terbutaline. We found no difference between groups in tocolysis or preterm birth. No serious maternal adverse effects or serious neonatal adverse outcome occurred in either group. Less serious maternal adverse effects less common with terbutaline included flushing (2.94% versus 43.7%) and headache (5.9% versus 31.2%). The administration of terbutaline increased tremor (76.4% versus 0%), nausea (58.8% versus 9.4%) and dizziness (29.4% versus 6.25%). The total number of side effects, and the proportion of women experiencing one or more side effects, proved greater with terbutaline. In this study, terbutaline and nifedipine performed similarly in their tocolytic effects. Each drug has specific side effects, although overall, nifedipine was associated with fewer adverse effects.  相似文献   
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