Use of cone beam computed tomography in identifying postmenopausal women with osteoporosis.

The aim of this study is to correlate radiometric indices from cone beam computed tomography (CBCT) images and bone mineral density (BMD) in postmenopausal women. Quantitative CBCT indices can be used to screen for women with low BMD. PURPOSE: Osteoporosis is a disease characterized by the deterioration of bone tissue and the consequent decrease in BMD and increase in bone fragility. Several studies have been performed to assess radiometric indices in panoramic images as low-BMD predictors. The aim of this study is to correlate radiometric indices from CBCT images and BMD in postmenopausal women. METHODS: Sixty postmenopausal women with indications for dental implants and CBCT evaluation were selected. Dual-energy X-ray absorptiometry (DXA) was performed, and the patients were divided into normal, osteopenia, and osteoporosis groups, according to the World Health Organization (WHO) criteria. Cross-sectional images were used to evaluate the computed tomography mandibular index (CTMI), the computed tomography index (inferior) (CTI (I)) and computed tomography index (superior) (CTI (S)). Student's t test was used to compare the differences between the indices of the groups' intraclass correlation coefficient (ICC). RESULTS: Statistical analysis showed a high degree of interobserver and intraobserver agreement for all measurements (ICC > 0.80). The mean values of CTMI, CTI (S), and CTI (I) were lower in the osteoporosis group than in osteopenia and normal patients (p < 0.05). In comparing normal patients and women with osteopenia, there was no statistically significant difference in the mean value of CTI (I) (p = 0.075). CONCLUSIONS: Quantitative CBCT indices may help dentists to screen for women with low spinal and femoral bone mineral density so that they can refer postmenopausal women for bone densitometry.

Vicariance and marine migration in continental island populations of a frog endemic to the Atlantic Coastal forest.

The theory of island biogeography is most often studied in the context of oceanic islands where all island inhabitants are descendants from founding events involving migration from mainland source populations. Far fewer studies have considered predictions of island biogeography in the case of continental islands, where island formation typically splits continuous populations and thus vicariance also contributes to the diversity of island populations. We examined one such case on continental islands in southeastern Brazil, to determine how classic island biogeography predictions and past vicariance explain the population genetic diversity of Thoropa taophora, a frog endemic to the Atlantic Coastal Forest. We used nuclear microsatellite markers to examine the genetic diversity of coastal and island populations of this species. We found that island isolation has a role in shaping the genetic diversity of continental island species, with island populations being significantly less diverse than coastal populations. However, area of the island and distance from coast had no significant effect on genetic diversity. We also found no significant differences between migration among coastal populations and migration to and from islands. We discuss how vicariance and the effects of continued migration between coastal and island populations interact to shape evolutionary patterns on continental islands.

Efeito da Partícula de Carga e do Tempo de Armazenamento sobrea Microdureza de Superfície de Compósitos Restauradores Estéticos / Effect of Load Particle and Storage Time on the Surface Microhardness of EstheticRestorative Composites

Objeti vo: Avaliar o efeito de diferentes tamanhos de partí culasde carga e diferentes tempos de armazenagem na durezasuperfi cial de três compósitos restauradores estéti cos.Método: Foram confeccionados 60 corpos-de-prova, emforma de pasti lhas, com 5mm de diâmetro e 2mm de altura,os quais foram divididos em seis grupos (n=10) de acordocom a resina avaliada: Filtek Z350 (3M/ESPE) com partí culasde tamanho médio classifi cado como nanoparti culado; FiltekZ250 (3M/ESPE) com partí culas de tamanho médio classifi cadocomo micro-híbrido; e Durafi ll (Heraeus-Kulzer) com partí culasde tamanho médio classifi cado como microparti culado. Asamostras foram armazenadas em água desti lada pelos períodosde 24h e 60 dias (37ºC) e, após cada período de armazenagem,submeti das ao teste de microdureza uti lizando-se um aparelhocom edentador do ti po Vickers pelo período de 45s e carga de50g. Os resultados (VHN) obti dos foram submeti dos à análiseestatí sti ca através dos testes de ANOVA e Tukey (α=0,05).Resultados: Os valores médios (±DP), no período de 24h,apresentados pelas resinas testadas foram de: Filtek Z250 –64,46 (±3,30); Filtek Z350 – 59,60 (±3,42); e Durafi ll – 21,69(±2,39). Após armazenagem pelo período de 60 dias os valoresmédios (±DP) apresentados foram de: Filtek Z250 – 71,07(±6,38); Filtek Z350 – 47,63 (±4,42); e Durafi ll – 23,72 (±3,50).Observou-se diferença signifi cante entre os grupos II, III,V e VI (p<0,005). Todavia, os grupos I e II não apresentaramsignifi cância entre si, mas diferiram dos demais grupos.Conclusão: O armazenamento em água desti lada e o tamanhomédio das partí culas de carga podem infl uenciar na microdurezade superfí cie de resinas compostas...

Objecti ve: To evaluate the eff ect of diff erent sizes ofload parti cles and diff erent storage ti mes on the surfacemicrohardness of three estheti c restorati ve composites.Method: Sixty disc-shaped specimens (5 mm diameter and 2mm high) were fabricated and divided into 6 groups (n=10)according to the evaluated resin: Filtek Z350 (3M/ESPE), withmedium-sized parti cles classifi ed as nanoparti culate; FiltekZ250 (3M/ESPE), with medium-sized parti cles classifi ed asmicro-hybrid; and Durafi ll (Heraeus-Kulzer), with medium-sizedparti cles classifi ed as microparti culate. The specimens werestored in disti lled water for 24 h and 60 days (37ºC) and, aft ereach storage period, they were subjected to the microhardnesstest using a Vickers indenter during 45 s using a 50 g load. Theresults (VHN) were subjected to stati sti cal analysis by ANOVAand Tukey’s test (α=0.05).Results: In the 24-hour period, the mean values (±SD) presentedby the tested resins were: Filtek Z250 – 64.46 (±3.30); FiltekZ350 – 59.60 (±3.42); and Durafi ll – 21.69 (±2.39). Aft er 60-daystorage, the mean values (±SD) presented by the tested resinswere: Filtek Z250 – 71.07 (±6.38); Filtek Z350 – 47.63 (±4.42);and Durafi ll – 23.72 (±3.50). There was stati sti cally signifi cantdiff erence between groups II, III, V and VI (p<0.005). However,groups I and II did not diff er signifi cantly from each other, butwere signifi cantly diff erent from the other groups.Conclusion: The storage in disti lled water and the size of theload parti cles can have infl uence on the surface microhardnessof estheti c composite resins...

Characterization of microsatellite markers for Thoropa taophora (Anura, Cycloramphidae), a frog endemic to the Brazilian Atlantic Rain Forest.

Here we characterize nine microsatellite loci for Thoropa taophora collected from a coastal and an island population in southeastern Brazil. The number of alleles per locus ranged from three to 11 for the coastal population and from two to eight for the island population. Observed heterozygosities ranged from 0.308 to 0.778 for the coastal population and from zero to 0.737 for the island population. One locus did not conform to Hardy-Weinberg expectations on the coast, while two were in disequilibrium on the island. These markers are currently being used to examine genetic differentiation and patterns of dispersal in T. taophora.

Exercise intolerance in patients with chronic heart failure: role of pulmonary diffusing limitation.

In order to test the hypothesis of pulmonary diffusing capacity involvement in exercise limitation in subjects with chronic heart failure (CHF), lung transfer factor (TLCO), oxygen saturation (SaO2), cardiac output (CO) and gas exchange were studied over the course of an incremental exercise test in 10 patients and 10 controls. The TLCO and transfer coefficient for carbon monoxide (TLCO/VA) were measured at rest and during recovery by the single breath method. The SaO2 was followed non-invasively with a finger oximeter and CO was determined according to the carbon dioxide rebreathing method. Analysis of respiratory variables at maximal effort showed significantly lower values in patients with CHF as regards peak oxygen uptake (VO2), minute ventilation (VE), heart rate (HR), oxygen pulse (O2 pulse), and CO with higher ventilatory reserve (VR) than controls. At a comparable workload (30 W), patients with CHF demonstrated higher values for VE and lower values for CO than controls. The TLCO, expressed as percent of predicted values, was significantly lower in CHF patients than controls, respectively, at rest (90.5 +/- 3.75% vs 106.8 +/- 3.8%) and within 5 min after maximal exercise (87 +/- 4.4% vs 117.4 +/- 3.81%). The TLCO/VA showed comparable data between the two groups at rest (81.7 +/- 3.28 vs 90.3 +/- 2.86%). However, significantly lower values of TLCO/VA were obtained for CHF after maximal exercise in comparison to control subjects (77.5 +/- 3.85% vs 96.3 +/- 3.95%). These results confirm the alteration of the main variables in relation to cardiopulmonary exercise limitation in-tHF, and indicate a significant decrease in TLCO and TLCO/VA after maximal exercise.(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiopulmonary exercise testing. Determinants of dyspnea due to cardiac or pulmonary limitation.

The aim of this study was to bring to light new and simple criteria, obtained during cardiopulmonary exercise testing, in order to demonstrate in patients the cardiac or the pulmonary origin of a comparable exertional dyspnea. Forty male subjects were compared, who exercised with a 30-W/3-min protocol and were divided into three groups: the cardiac heart failure (CHF) group (n = 15), the chronic obstructive lung disease (COLD) group (n = 15), and the control group (n = 10). The two groups of patients differed totally from the control group concerning their spirometric values at rest and a clear inability during effort which was confirmed by all the studied cardiopulmonary parameters at maximal exercise. The CHF and COLD groups differed slightly concerning their maximum symptom-limited oxygen uptake, only when related to body mass (13.26 +/- 0.69 ml/kg/min in CHF group, 17.05 +/- 1.59 ml/kg/min in COLD group; p < 0.05), and concerning their maximum ventilatory equivalent for oxygen which tended to be higher in the CHF group in comparison with the COLD group (p = 0.082). Furthermore, and as foreseen, the two groups of patients clearly differed at maximum exercise concerning the ventilatory reserve respiratory parameter (49.73 +/- 3.18 percent in CHF group, 8.38 +/- 5.85 percent in COLD group; p < 0.01). On the other hand, they did not differ concerning cardiac parameters or those considered as such (maximum heart rate [HR], HR reserve, HR response, maximum O2 pulse measurement). While their maximum ventilation was similar in the CHF and COLD groups, a difference in adaptation during exercise was found by observing their breathing pattern. In the CHF group, this was demonstrated by a significantly lower breathing frequency at maximum exercise (31.24 +/- 1.53 beats/min vs 37.75 +/- 2.24 beats/min; p < 0.05) and a tidal volume that tended to be higher at maximum exercise (p = 0.077) and significantly higher at 60-W work load (p < 0.05). This work shows that the study of ventilatory reserve and breathing pattern during exercise testing allows one to discriminate if dyspnea on exertion in patients is due to cardiac or respiratory disease.