Fluorosis, caries and oral hygiene in schoolchildren on the Ombili Foundation in Namibia.

PURPOSE: The aim of the present study was to analyse caries prevalence and fluorosis as well as oral hygiene habits in schoolchildren in north Namibia. MATERIALS AND METHODS: In 2004, 120 pupils (1st to 8th grade, mean age: 12.3 ± 2.8 years) of the Ombili Primary School were examined by one calibrated clinician for caries (DMFT) according to the World Health Organization criteria, oral hygiene (API) and fluorosis (Dean's index), categorised according to the four different farms where they lived. In addition, samples of drinking water were obtained from the wells of the farms and analysed for quality and mineral content. RESULTS: The pupils at the different farms showed very different caries prevalence (range: 17% to 50% caries-free children) and mean DMFT values (0.96 to 2.67). Oral hygiene measures were not common (60.8% none) or inefficient (mean proximal plaque index: 89.5%) and did not differ greatly between the different farms. The fluoride concentration in drinking water varied considerably (0.28 to 1.06 mg/l). The prevalence of dental fluorosis in all schoolchildren was 65.8%, the Community Fluorosis Index (CFI) was 1.41 and it differed clearly for pupils from the four farms (CFI: 0.5 to 1.65). The DMFT index showed a statistically significant correlation with the fluoride concentration of the drinking water (P < 0.05). CONCLUSIONS: Based on these results, fluoride concentration in drinking water should be monitored in the future. In parallel, a caries-preventive programme should be developed, as high concentrations of fluoride in drinking water alone do not result in acceptable caries levels.

Sealing properties of a new root canal sealer.

AIM: To evaluate bacterial leakage of Apexit Plus, a new root canal sealer, in comparison with AH Plus. METHODOLOGY: A total of 56 single-rooted human teeth were randomly divided into two experimental groups of 16 roots and two control groups. Roots were filled by lateral condensation with Gutta-percha and AH Plus or with Gutta-percha and Apexit Plus. A split chamber microbial leakage model was used in which Streptococcus mutans placed in the upper chamber could reach the lower chamber only through the filled canal. Positive controls were filled only with Gutta-percha and tested with bacteria, whereas negative controls were sealed with wax to test the seal between chambers. Additionally, film thickness, solubility and dimensional change were determined. RESULTS: All positive controls leaked within 24 h, whereas none of the negative controls leaked after 30 days. Apexit Plus had significant less bacterial leakage (log-rank test, P < 0.0001) than AH Plus. AH Plus (0.3% solubility) showed a slightly lower solubility than Apexit Plus (0.5% solubility) but a larger film thickness (28 vs. 11 mum) according to ISO 6876:2001. CONCLUSION: Apexit Plus had a better sealing ability in comparison with AH Plus.

Reference values for maximum work rate in apparently healthy Dutch/Flemish adults: data from the LowLands fitness registry.

Background: The peak oxygen uptake (VO2peak) test is the gold standard for cardiorespiratory fitness. However, the test is demanding, requiring sophisticated apparatus for measuring the oxygen uptake. Peak work rate (WRpeak) testing is a promising substitute for peak VO2peak testing. However, there is a paucity of research conducted to determine reference values (RVs) for WRpeak. Methods: The database from the LowLands fitness registry was used, containing data from health checks from apparently healthy subjects among various professions. Exercise tests were performed using a cycle ergometer and a calibrated metabolic cart. Analysis was executed on 3463 subjects, 2868 male and 595 female. Reference values with corresponding centiles were developed using the LMS method. Results: VO2peak and WRpeak where highly associated with Pearson's correlation of 0.9 (p = .001). Weight, height, maximum heart rate, and the respiratory exchange ratio had a positive significant effect (p < .001) on WRpeak, and age a negative significant effect, in both males and females. The following formulas were computed for RVs: WRpeak=-102+(1.5 * weight[kg])+(1.9 * height[cm])-(2.0 * age)-(sex * 60[M:0;V:1]) WRpeak/kg=2.45-(0.026 * weight[kg])+(0.024 * height[cm])-(0.024 * age)-(sex * 0.84 [M:0;V:1]) Conclusions: WRpeak can be used as a substitute for VO2peak when a respiratory gas-analysis system is not available. This study provides RVs for WRpeak and WRpeak/kg in a healthy Dutch/Flemish adult population using cycle ergometry. Further research is needed to obtain RVs for elderly subjects, specific diseases, ethnicities and ergometers.

Doppler echocardiographic measurement of pulmonary artery pressure from ductal Doppler velocities in the newborn.

The ductal flow velocities in 37 newborns (group 1: persistent pulmonary hypertension [n = 16], transient tachypnea [n = 3], other [n = 2]; group 2: respiratory distress syndrome [n = 16]) were prospectively evaluated by Doppler ultrasound for the purpose of deriving systolic pulmonary artery pressures. Maximal tricuspid regurgitant Doppler velocity in 21 of these patients was used to validate the pulmonary artery pressures derived from ductal flow velocities. There was a significant linear correlation between tricuspid regurgitant Doppler velocity and pulmonary artery systolic pressure derived from ductal Doppler velocities in patients with unidirectional (pure left to right or pure right to left) ductal shunting (p less than 0.001, r = 0.95, SEE 8) and in those with bidirectional shunting (p less than 0.001, r = 0.95, SEE 4.5). Systolic pulmonary artery pressure in group 1 (67 +/- 13 mm Hg) was significantly higher than that in group 2 (39 +/- 10 mm Hg) (p less than 0.001). In those with bidirectional shunting, duration of right to left shunting less than 60% of systole was found when pulmonary artery pressure was systemic or less, whereas duration greater than or equal to 60% was associated with suprasystemic pulmonary artery pressures. Serial changes in pulmonary artery systolic pressure, reflected by changes in ductal Doppler velocities, correlated with clinical status in persistent pulmonary hypertension of the newborn. Persistently suprasystemic pulmonary artery pressure was associated with death in five group 1 patients. It is concluded that ductal Doppler velocities can be reliably utilized to monitor the course of pulmonary artery systolic pressures in newborns.

Cardiac dysfunction late after cardiotoxic therapy for childhood cancer.

Despite a wealth of data documenting acute cardiac injury from anthracycline therapy and/or mediastinal radiotherapy used for childhood cancer, little information is available on the long-term consequence of these insults. Twenty-nine patients (mean age 15 +/- 4.3 years) from The Late Effects Follow-Up Clinic For Childhood Cancer study, who had been in continuous, complete remission and off chemotherapy for a minimum of 2 years (mean follow-up 7.2 +/- 3.2) were studied. All patients had normal ejection fractions before and during cancer therapy and all were in New York Heart Association class I at the time of study. Systolic and diastolic functions were assessed by 2-dimensional echocardiography, Doppler flow velocity, and radionuclide angiography, and results were compared with normal control subjects. Left ventricular mass and mass index were significantly reduced in the patient population. Fractional shortening was decreased overall and end-systolic wall stress was much higher in patients than in controls. However, contractility, as assessed by the relation of wall stress to rate-corrected velocity of shortening, was decreased by > or = 2 SDs in only 6 of 28 patients, and the force-mass relation was actually increased in the patient group as a whole. Mitral valve inflow velocities were significantly increased but the pattern was abnormal. These results suggest a pattern consistent with a thin-walled, complaint left ventricle with reduced muscle mass performing under above-normal levels of wall stress. Contractility measurements were normal or increased in the group, but some patients clearly demonstrated development of reduced contractile function.(ABSTRACT TRUNCATED AT 250 WORDS)

Results of the Fontan procedure for patients with univentricular heart.

One hundred twenty-four consecutive patients with univentricular heart undergoing the Fontan operation were reviewed. Patients with tricuspid atresia or biventricular heart with hypoplasia of one ventricle were excluded. Eighty-four patients had left ventricular morphology. Atrioventricular connection was double-inlet (n = 76), common (n = 29), absent left atrioventricular connection (n = 14), and absent right atrioventricular connection (n = 5). Actuarial survival was 77% (70% confidence limits, 73% to 81%) at 1 year, 66% (70% confidence limits, 60% to 72%) at 5 years, and 49% (70% confidence limits, 36% to 61%) at 10 years, indicating a continuing risk for premature death. Multivariate analysis identified preoperative ventricular function and hypertrophy as risk factors for survival. High postrepair right atrial pressure (greater than 15 mm Hg) emerged as a strong intraoperative predictor of survival. Logistic regression analysis of these factors predicts high probability of death for certain subgroups of patients after the Fontan operation. Forty-four percent (n = 53) of these original 124 patients are alive and in New York Heart Association class I at follow-up. Thirty-eight percent (n = 33) of survivors have worse ventricular function than preoperative. Long-term survival is disappointing. Certain identifiable subgroups of patients with univentricular heart have unacceptable risks for the Fontan operation and should have alternate management. High postrepair right atrial pressure is an ominous sign, and if it persists the Fontan should be fenestrated or taken down.

Electromyographic analysis of knee exercises in healthy subjects and in patients with knee pathologies.

Little information exists about the intensity of contraction required from knee and hip musculature during common therapeutic exercises used for patient populations. This study, therefore, was designed to compare electromyographic data obtained from the vastus medialis, rectus femoris, gluteus medius, and biceps femoris muscles during maximally resisted straight-leg-raising (SLR) exercises with EMG data obtained from the same muscles during quadriceps femoris muscle setting (QS) exercises in healthy subjects and in patients with knee pathologies. Of the 30 participants in the study, 16 had a history of knee injury or surgery. All participants performed randomly ordered trials of the SLR and QS exercises while the EMG data were recorded from surface electrodes and normalized to values derived from maximal effort isometric contraction trials. An analysis of variance demonstrated significantly greater activity (p less than .05) of the vastus medialis, biceps femoris, and gluteus medius muscles during QS exercises than during SLR exercises. The rectus femoris muscle was significantly more active (p less than .05) during SLR exercises than during QS exercises. The study demonstrated remarkably different degrees of muscle activation between the SLR and QS exercises, indicating that the exercise selected will affect the therapeutic intention.

Echocardiographic and hemodynamic characteristics of reconstructed bicuspid aortic valves at rest and exercise.

Repair of diseased bicuspid aortic valves has gained increasing interest as an alternative to conventional valve replacement. Hemodynamic data at exercise have not been reported before. The aim of this study was to investigate the clinical and echocardiographic status of patients after bicuspid aortic valve repair at rest and exercise. Between 03/94 and 09/02 a reconstruction of an incompetent bicuspid aortic valve was performed in 25 patients (mean age 35+/-12.1 years, group A, mean insufficiency 2.8 preoperatively). Patients were investigated clinically and echocardiographically after 2.1+/-2.4 (0.1-8.9) years at rest and exercise and compared to 20 controls (group B). Clinical followup was complete. There were no deaths, reoperations, thromboembolic or bleeding complications. At last examination 21 patients were in NYHA class I, n=4 in NYHA class II and mean aortic valve insufficiency (AI) was 1.0 with one patient having an AI>II degrees. Maximum and mean pressure gradient (dPmax/mean) across the aortic valve at rest were 14+/-5.5/7+/-2.6 mmHg for patients of group A and 7+/-2.5/3.6+/-1.1 mmHg in group B. Mean AVA at rest was 2.6+/-0.8 (group A) vs 2.9+/-0.6 cm(2) (group B, p=0.025), valvular resistance 13.4+/-4.8 (group A) vs 13.6+/-2.9 dyn x s x cm(-5) (group B, p>0.05). All individuals were stressed up to 100 W (dPmax/mean 21+/-6.8/11+/-3.6, group A vs 11+/-2.9/6+/-1.3 mmHg, group B). 56% of group A and 85% of group B could be stressed up to 175 W with dPmax/mean 24.5+/-8.3/12+/-4.2 and 16+/-3.6/8+/-1.4 mmHg, respectively (p<0. 01). Heart rate and blood pressure behavior were comparable. Left ventricular mass regression (preoperatively 369.3+/-76.4 vs 277.3+/-80.7 g at last examination, p<0.01) was significant in group A but did not reach normal values (group B, 227.8+/-71.1; p<0.01). Bicuspid aortic valve reconstruction reduces left ventricular volume load significantly. Although residual mild subclinical obstruction and incompetence were observed, the behavior of hemodynamics at exercise was comparable to controls. The clinical relevance of these findings in long term follow-up has to be evaluated.

Perioperative respiratory compliance in children undergoing repair of atrial septal defects.

Children with atrial septal defects (ASD) have less respiratory compliance (Crs) than normal cohorts. There could be implications for anaesthetic management if these children also have decreased compliance during anaesthesia. To examine the changes in Crs before, during and following surgical correction of the atrial defect, Crs was measured in 29 infants and children, 15 undergoing correction of secundum type atrial septal defects, and a group of 14 children of similar weight undergoing non-thoracic surgery. During sedation, Crs was measured using the single breath technique (SBT) and during anaesthesia, both before and after the surgical procedure, an inflation technique was applied to determine Crs. To investigate the aetiology of the difference in Crs, the pulmonary to systemic flow ratio (Qp:Qs) was determined using echocardiography during sedation in the ASD patients. During sedation, Crs in the ASD group was 52.7 +/- 19.5% less than in the control group. The slope of the line of regression of Crs vs height for the ASD group was significantly less (P less than 0.05) than that of the control group during sedation. However, during anaesthesia, Crs in the ASD group was not significantly different from the control group either before or after surgery. The per cent decrease in Crs during sedation in the children with ASD, in comparison with the control group, did not correlate with the Qp:Qs ratio of the ASD group (r2 = 0.012,NS). We conclude that, in spite of lower Crs during sedation, infants and children with ASD do not have lower Crs during anaesthesia and cardiopulmonary bypass than normal controls undergoing non-thoracic surgery.(ABSTRACT TRUNCATED AT 250 WORDS)

The quiescin Q6 gene (QSCN6) is a fusion of two ancient gene families: thioredoxin and ERV1.

Cell and tissue growth is a dynamic process determined by the fraction of cells in the proliferative cycle, the fraction of cells in quiescence, and the rate of cell death. Genes whose expression is induced at the beginning of the transition from the proliferative cell cycle to quiescence may play an important role in this process. We have identified a gene, Quiescin Q6 (QSCN6), whose expression is induced just as fibroblasts begin to leave the proliferative cycle and enter quiescence. QSCN6 is located on human chromosome 1q24, near the putative hereditary prostate cancer locus (HPC1). A triplet repeat (CTG)n encodes a putative signal sequence. The gene encodes a 582-amino-acid open reading frame that has domains that are members of two ancient gene families. These domains apparently underwent a gene fusion event during metazoan evolution to create QSCN6. QSCN6 is most closely related to three genes of unknown function from Caenorhabditis elegans as well as a gene from guinea pig. Analysis of this relationship showed nine Quiescin homology zones (QHZ). QHZ 0 is the putative signal sequence, QHZ 1 is homologous to a thioredoxin domain, and QHZ 2, 3, 4, and 8 are homologous only to themselves, while QHZ 5, 6, and 7 are homologous to the ERV1 gene of Saccharomyces cerevisiae. In both thioredoxin and ERV1 gene superfamilies, QSCN6 sequences appear to be on distinct branches of their respective phylogenetic trees, consistent with an ancient origin of the QSCN6 gene. We present a model of the origin of QSCN6 and discuss its potential role in growth regulation.

Infections complicating low-risk cesarean sections in community hospitals: efficacy of antimicrobial prophylaxis.

A prospective study of women with low-risk cesarean sections was conducted in four community hospitals to determine the frequency of postoperative infections and identify factors predisposing to endometritis and wound infection. Low-risk cesarean section was defined as a scheduled procedure without an urgent indication, with any duration of ruptured membranes being less than or equal to 12 hours. In a cohort of 1863 patients, 26 (1.4%) developed endometritis and 21 (1.1%) had wound infections. Primary cesarean section was associated with endometritis in the cohort (p less than 0.01) and in a retrospective study with the same cases as in the cohort (p = 0.01). Absence of antibiotic prophylaxis was associated with endometritis (p less than or equal to 0.013) or endometritis with wound infection (p less than 0.01) in both studies. Without prophylaxis 37 such infections occurred in 957 (3.7%) women; with prophylaxis eight infections occurred in 906 (0.9%) women. Routine timely antibiotic prophylaxis in low-risk cesarean sections could lead to an annual national savings of approximately $9 million.

Regulation of the quiescence-induced genes: quiescin Q6, decorin, and ribosomal protein S29.

The transition from growth to quiescence is deeply deranged in cancer cells. Expression of the quiescence-induced genes, quiescin Q6, decorin, and S29, was examined in important physiological states and in several cell types. Senescent fibroblasts expressed neither Q6 nor decorin mRNAs. The quiescins were induced in serum-deprived cultures. Trypsinized cells, which rapidly reattached to the culture dish, expressed Q6, S29, and decorin mRNAs at reduced levels, compared to those that remained in suspension. Expression of Q6 and S29 mRNAs in endothelial cells was low in growth phase and high in quiescent cells. Q6 and S29 mRNAs were found in a large variety of human tissues. The quiescin Q6 protein was detected in WI38 cell extracts and in conditioned medium from quiescent cells. A complex regulation of the quiescins by growth and attachment status in specific cell types may be of importance in pathological growth regulation and the development of cancer.