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81.

Introduction and objectives

Tonsilloliths and abnormal stylohyoid complex may have similar symptoms to others of different aetiology. Individuals with cleft lip and palate describe similar symptoms because of the anatomical implications that are peculiar to this anomaly. The aim of this study was to determine the prevalence of abnormal stylohyoid complex and tonsilloliths on cone beam computed tomography in individuals with cleft lip and palate.

Methods

According to the inclusion and exclusion criteria, 66 CT scans out of of 2,794 were analysed, on i- Cat ® vision software with 0.8 index Kappa intra-examiner.

Results

The total prevalence of ossification of the incomplete stylohyoid complex in individuals with cleft lip and palate was 66.6%; the prevalence of these findings in females was 75% and 61.9% in males. The total prevalence of tonsilloliths was 7.5%.

Conclusion

It is important to ascertain calcification of the stylohyoid complex and tonsilloliths in the radiological report, due to the anatomical proximity and similarsymptomatology to other orofacial impairments inindividuals with cleft lip and palate, focusing on females with oral cleft formation, patients with incisive trans foramen cleft and incisive post foramen cleft because they are more prevalent. Greater knowledge of the anatomical morphometry of individuals with cleft lip and palate greatly contributes towards the selection of clinical behaviours and the quality of life of these patients, since cleft lip and palateis one of the most common anomalies.  相似文献   
82.
83.
ABSTRACT

Tannery effluents consist of a complex chemical composition not only limited to primary pollutants, which also require biological detection as these compounds may produce adverse effects. The fish embryo toxicity (FET) test with Danio rerio is an alternative method in hazard and risk assessment for determination of chemical-mediated effects. The aim of this investigation was to use the FET test to detect compounds and consequent effects in Brazilian tannery effluents. Samples were collected from the inlet and outlet of the effluent treatment plant at a tannery located in Restinga, São Paulo, Brazil. The toxicological effects were assessed using FET assay for a period of 144 hr using indices such as (1) coagulation of fertilized eggs, (2) lack of detachment of tail-bud from yolk sac, (3) absence of spontaneous movement, (4) yolk sack edema, (5) malformation of the tail, (6) scoliosis, and (7) deformation of swim bladder in the embryos. Data showed that effluent treatment plant exposure produced acute toxicity in D. rerio embryos as evidenced by coagulation of fertilized eggs in up to 5% of all diluted samples 24 hr post fertilization for inlet effluent samples compared to 100% coagulation for outlet samples. Results demonstrated that these effects may not be attributed to metals, but to other non-detected components, such as dyes, pigments, biocides, carriers, surfactants, or other organic compounds that might be present in these complex mixtures. The use of D. rerio embryos was found to be useful as an additional tool for ecotoxicity testing to assess the potential environmental acute toxicity influence of tannery effluents.  相似文献   
84.
BACKGROUND: The aim of the present study was to assess the incidence, severity, and extension of periodontal disease among young subjects. METHODS: Three hundred sixty subjects from a public school in Belo Horizonte, Brazil were examined. Forty-four subjects with bone loss (BL) and/or clinical attachment loss (CAL) > or = 4 mm, and no dental care during the following 52 months, were considered the reference sample and were recalled for a second examination. At both examinations, statistical analyses were performed for CAL and BL for subject, tooth, and site. Comparisons of CAL at subject, tooth, and site levels were performed with the Wilcoxon test for matched samples. Comparisons of BL at subject, tooth, and site levels were performed with the McNemar and Student t tests for dependent samples. RESULTS: Findings indicated an increase in the number of sites with CAL >4 mm from baseline to follow-up. Sites that exhibited BL increased from 2.14% at baseline to 7.5% at follow-up (P <0.001). The severity of periodontitis was characterized by increased CAL values at affected sites at both examinations (P <0.001) and an increase in BL over time (mean BL at 35 affected sites was 2.6 mm at baseline and 3.5 mm at follow-up; P = 0.001). In addition, a 34% incidence of BL was verified. CONCLUSIONS: The incidence, severity, and extension of CAL and BL were significant findings. They indicate the importance of early detection of the disease and the need for preventive health care programs geared toward young subjects.  相似文献   
85.
BACKGROUND: It has been suggested that periodontitis is associated with systemic alterations such as adverse pregnancy outcomes. However, some conflicting results have been reported. This case-control study was conducted to determine the association between maternal periodontitis and preterm birth (PTB), low birth weight (LBW), and intrauterine growth restriction (IUGR). METHODS: A total of 1,305 Brazilian women from multiethnic groups were enrolled and divided into four groups: control group (1,042 women who gave birth to infants with adequate gestational age and birth weight); PTB group (238 women, gestational age <37 complete weeks); LBW group (235 women, birth weight <2,500 g); and IUGR group (77 women who gave birth to infants with fetal growth retardation). Periodontitis was defined as the presence of at least four teeth with one or more sites with probing depth > or =4 mm and clinical attachment loss > or =3 mm. The effects of variables of interest, confounders, and interaction were tested through univariate and multivariate logistic regression tests. RESULTS: After adjusting for variables of interest, maternal periodontitis was retained in the final model for PTB (odds ratio [OR] = 1.77; 95% confidence interval [CI]: 1.12 to 2.59), LBW (OR = 1.67; 95% CI: 1.11 to 2.51), and IUGR (OR = 2.06; 95% CI: 1.07 to 4.19). When the interaction between periodontitis and previous PTB was tested, an OR of 5.94 (P <0.001), 9.12 (P <0.001), and 18.90 (P <0.001) was observed for PTB, LBW, and IUGR, respectively. CONCLUSIONS: Maternal periodontitis is associated with an increased risk for PTB, LBW, and IUGR. Results emphasize the importance of periodontal care in prenatal health programs.  相似文献   
86.
87.
We investigated the relationship between retinal layers and normal‐appearing white matter (WM) integrity in the brain of patients with relapsing‐remitting multiple sclerosis (MS), using a combined diffusion tensor imaging and high resolution optical coherence tomography approach. Fifty patients and 62 controls were recruited. The patients were divided into two groups according to presence (n = 18) or absence (n = 32) of optic neuritis. Diffusion tensor data were analyzed with a voxel‐wise whole brain analysis of diffusion metrics in WM with tract‐based spatial statistics. Thickness measurements were obtained for each individual retinal layer. Partial correlation and multivariate regression analyses were performed, assessing the association between individual retinal layers and diffusion metrics across all groups. Region‐based analysis was performed, by focusing on tracts associated with the visual system. Receiver operating characteristic (ROC) curves were computed to compare the biomarker potential for the diagnosis of MS, using the thickness of each retinal layer and diffusion metrics. In patients without optic neuritis, both ganglion cell layer (GCL) and inner plexiform layer thickness correlated with the diffusion metrics within and outside the visual system. GCL thickness was a significant predictor of diffusion metrics in the whole WM skeleton, unlike other layers. No association was observed for either controls or patients with a history of optic neuritis. ROC analysis showed that the biomarker potential for the diagnosis of MS based on the GCL was high when compared to other layers. We conclude that GCL integrity is a predictor of whole‐brain WM disruption in MS patients without optic neuritis.  相似文献   
88.
Graefe's Archive for Clinical and Experimental Ophthalmology - It has remained a mystery why some genetic mitochondrial disorders affect predominantly specific cell types such as the retinal...  相似文献   
89.

Objective

To investigate the Bereitschaftspotential (BP) preceding spontaneous and voluntary eyelid blinks in normal subjects.

Methods

Eighteen healthy individuals (10 female) between 17 and 60 years (mean 35) were studied. The EEG was recorded from 11 scalp positions of the 10–20 international electrode placement system referenced to linked mastoids. The vertical electrooculogram (VEOG) was recorded from two electrodes positioned above and below the right eye. The ground electrode was placed in the right clavicle. The recordings were obtained during spontaneous and voluntary eyelid blinks. Two-second EEG segments before the onset of the blink potential (visually identified at the VEOG channel) were averaged and analyzed off-line. The statistical significance of differences was evaluated by repeated-measures analysis of variance with Geisser–Greenhouse correction for violation of sphericity and the Newman–Keuls test was used for post hoc comparisons.

Results

A BP starting around ?1700 ms prior to the onset of voluntary blink was observed; it had average amplitude in the negative peak of 3.3 μV. There was no BP preceding spontaneous blinking.

Conclusion

A BP precedes voluntary blinks but not spontaneous blinks.

Significance

This is the first study evaluating the BP preceding spontaneous and voluntary eye blinks.  相似文献   
90.

Purpose

The recent publication of the ACOSOG Z1031 trial results demonstrated that Ki-67 proliferation marker-based neoadjuvant endocrine therapy response monitoring could be used for tailoring the use of adjuvant chemotherapy in ER+HER2-negative breast cancer patients. In this paper, we describe the development of the Ki-67 clinical trial assay used for this study.

Methods

Ki-67 assay assessment focused on reproducing a 2.7% Ki-67 cut-point (CP) required for calculating the Preoperative Endocrine Prognostic Index and a 10% CP for poor endocrine therapy response identification within the first month of neoadjuvant endocrine treatment. Image analysis was assessed to increase the efficiency of the scoring process. Clinical outcome concordance for two independent Ki-67 scores was the primary performance metric.

Results

Discordant scores led to a triage approach where cases with complex histological features that software algorithms could not resolve were flagged for visual point counting (17%). The final Ki-67 scoring approach was run on T1/2 N0 cases from the P024 and POL trials (N = 58). The percent positive agreement for the 2.7% CP was 87.5% (95% CI 61.7–98.5%); percent negative agreement 88.9% (95% CI: 65.3–98.6%). Minor discordance did not affect the ability to predict similar relapse-free outcomes (Log-Rank P = 0.044 and P = 0.055). The data for the 10% early triage CP in the POL trial were similar (N = 66), the percentage positive agreement was 100%, and percent negative agreement 93.55% (95% CI: 78.58–99.21%). The independent survival predictions were concordant (Log-rank P = 0.0001 and P = 0.01).

Conclusions

We have developed an efficient and reproducible Ki-67 scoring system that was approved by the Clinical Trials Evaluation Program for NCI-supported neoadjuvant endocrine therapy trials. Using the methodology described here, investigators are able to identify a subgroup of patients with ER+HER2-negative breast cancer that can be safely managed without the need of adjuvant chemotherapy.
  相似文献   
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