Accuracy of stone casts obtained by different impression materials

Several impression materials are available in the Brazilian marketplace to be used in oral rehabilitation. The aim of this study was to compare the accuracy of different impression materials used for fixed partial dentures following the manufacturers' instructions. A master model representing a partially edentulous mandibular right hemi-arch segment whose teeth were prepared to receive full crowns was used. Custom trays were prepared with auto-polymerizing acrylic resin and impressions were performed with a dental surveyor, standardizing the path of insertion and removal of the tray. Alginate and elastomeric materials were used and stone casts were obtained after the impressions. For the silicones, impression techniques were also compared. To determine the impression materials' accuracy, digital photographs of the master model and of the stone casts were taken and the discrepancies between them were measured. The data were subjected to analysis of variance and Duncan's complementary test. Polyether and addition silicone following the single-phase technique were statistically different from alginate, condensation silicone and addition silicone following the double-mix technique (p < .05), presenting smaller discrepancies. However, condensation silicone was similar (p > .05) to alginate and addition silicone following the double-mix technique, but different from polysulfide. The results led to the conclusion that different impression materials and techniques influenced the stone casts' accuracy in a way that polyether, polysulfide and addition silicone following the single-phase technique were more accurate than the other materials.

Ureteroscopy in Pregnant Women for Ureteral Stone

Introduction: The occurrence of urolithiasis in pregnancy represents a challenge in both diagnosis and treatment of this condition, because it presents risks not only to the mother but also to the fetus. Surgical treatment may be indicated for patients with infection, persistent pain, and obstruction of a solitary kidney. We present our experience on the management of pregnant patients with ureteral calculi and a review of the literature. Materials and Methods: The charts of 19 pregnant patients with obstructive ureteral calculi were retrospectively reviewed. Gestational age ranged from 13 to 33 weeks. In all patients, ureteral stone was diagnosed on abdominal ultrasound. In regard to localization, 15 calculi were in the distal ureter, 3 in the proximal ureter, and 1 in the interior of an ureterocele. Calculi size ranged from 6 to 10 mm (mean, 8 mm). The following criteria were used to indicate ureteroscopy: persistent pain with no improvement after clinical treatment, increase in renal dilation, or presence of uterine contractions. Nine patients (47.3%) were submitted to ureteroscopy. All calculi (100%) were removed with a stone basket extractor under continuous endoscopic vision. None of the calculi demanded the use of a lithotriptor. Results: Nine patients (47.3%) treated with clinical measurements presented no obstetric complications and spontaneous elimination of the calculi. Nine patients (47.3%) submitted to ureteroscopy had no surgical complications. There was remission of pain in all cases after ureteroscopy and ureteral catheter placement. Conclusion: The diagnosis and treatment of ureteral lithiasis in pregnant women present potential risks for the fetus and the mother. Conservative management is the first option, but ureteroscopy may be performed with safety and high success rates.

Detection of high-velocity material from the wind-wind collision zone of Eta Carinae across the 2009.0 periastron passage

We report near-infrared spectroscopic observations of the Eta Carinae massive binary system during 2008-2009 using the CRIRES spectrograph mounted on the 8m UT 1 Very Large Telescope (VLT Antu). We detect a strong, broad absorption wing in He I lambda 10833 extending up to -1900 km s(-1) across the 2009.0 spectroscopic event. Analysis of archival Hubble Space Telescope/Space Telescope Imaging Spectrograph ultraviolet and optical data identifies a similar high-velocity absorption (up to -2100 km s(-1)) in the ultraviolet resonance lines of Si IV lambda lambda 1394, 1403 across the 2003.5 event. Ultraviolet resonance lines from low-ionization species, such as Si II lambda lambda 1527, 1533 and CII lambda lambda 1334, 1335, show absorption only up to -1200 km s(-1), indicating that the absorption with velocities -1200 to -2100 km s(-1) originates in a region markedly more rapidly moving and more ionized than the nominal wind of the primary star. Seeing-limited observations obtained at the 1.6m OPD/LNA telescope during the last four spectroscopic cycles of Eta Carinae (1989-2009) also show high-velocity absorption in He I lambda 10833 during periastron. Based on the large OPD/LNA dataset, we determine that material with velocities more negative than -900 km s(-1) is present in the phase range 0.976 <= phi <= 1.023 of the spectroscopic cycle, but absent in spectra taken at phi <= 0.947 and phi >= 1.049. Therefore, we constrain the duration of the high-velocity absorption to be 95 to 206 days (or 0.047 to 0.102 in phase). We propose that the high-velocity absorption component originates in shocked gas in the wind-wind collision zone, at distances of 15 to 45 AU in the line-of-sight to the primary star. With the aid of three-dimensional hydrodynamical simulations of the wind-wind collision zone, we find that the dense high-velocity gas is along the line-of-sight to the primary star only if the binary system is oriented in the sky such that the companion is behind the primary star during periastron, corresponding to a longitude of periastron of omega similar to 240 degrees-270 degrees. We study a possible tilt of the orbital plane relative to the Homunculus equatorial plane and conclude that our data are broadly consistent with orbital inclinations in the range i = 40 degrees-60 degrees.

Passage of radiation through wormholes of arbitrary shape

We study quasinormal modes and scattering properties via calculation of the S matrix for scalar and electromagnetic fields propagating in the background of spherically symmetric and axially symmetric traversable Lorentzian wormholes of a generic shape. Such wormholes are described by the general Morris-Thorne ansatz. The properties of quasinormal ringing and scattering are shown to be determined by the behavior of the wormhole's shape function b(r) and shift factor Phi(r) near the throat. In particular, wormholes with the shape function b(r), such that b(dr) approximate to 1, have very long-lived quasinormal modes in the spectrum. We have proved that the axially symmetric traversable Lorentzian wormholes, unlike black holes and other compact rotating objects, do not allow for superradiance. As a by-product we have shown that the 6th order WKB formula used for scattering problems of black or wormholes gives quite high accuracy and thus can be used for quite accurate calculations of the Hawking radiation processes around various black holes.

Dimension stone for building facades: methodology for structural design

The importance of a careful selection of rocks used in building facade cladding is highlighted. A simple and viable methodology for the structural detailing of dimension stones and the verification of the global performance is presented based on a Strap software simulation. The results obtained proved the applicability of the proposed structural dimensioning methodology which represents an excellent simple tool for dimensioning rock slabs used for building facade cladding. The Strap software satisfactorily simulated the structural conditions of the stone slabs under the studied conditions, allowing the determination of alternative slab dimensions and the verification of the cladding strength at the support.

Stone fruit injuries and damage at the wholesale market of Sao Paulo, Brazil

Mechanical injuries and diseases in stone fruit are important causes for market rejection. The objectives of this research were to quantify and characterize the mechanical injuries and diseases in peaches, nectarines and plums at Sao Paulo`s wholesale market, the largest in Brazil. Incidence of injuries was assessed weekly in 1 % of the marketed fruit (2973 fruit/week), from September to December in 2003 and 2004. Mechanical injuries were the most frequent injuries in both years, ranging from 8.73% (plum) to 44.5% (nectarine) of injured fruit. There was a significant positive correlation between the incidence of postharvest mechanical injuries and postharvest diseases. Incidence of postharvest diseases varied from 2.5% to 6.6%. Cladosporium rot (Cladosporium sp.) and brown rot (Monilinia fructicola) were the most frequent diseases, and were mostly detected in the apexes of nectarines and peaches. Aurora (peach), Sunraycer (nectarine) and Gulfblaze (plum) varieties were the most susceptible to injuries and diseases. (c) 2007 Elsevier B.V. All rights reserved.

Evaluation of the Experimental Inoculation of Cryptococcus albidus and Cryptococcus laurentii in Normal Mice: Virulence Factors and Molecular Profile Before and After Animal Passage

The genus Cryptococcus includes free-developing species, a few of which are of medical importance. Some, such as C. neoformans and C. gattii, cause infections in man frequently and C. albidus and C. laurentii cause less so. The aims of this study were to evaluate organ colonization after inoculation of C. albidus and C. laurentii isolates in normal BALB/c mice, the virulence factors (growth at 37A degrees C, capsule, melanin, proteinase, and phospholipase production) and the molecular profile (PCR-fingerprinting) of the yeasts before and after infection. The importance of different profiles (virulence and molecular) was considered in relation to the distribution in different organs and to the time intervals of isolation from organs. C. albidus was isolated from animal organs 2 to 10 days after inoculation and C. laurentii from 2 to 120 days. Most isolates of the two species kept the virulence factors showed before inoculation. The high homogeneity of the molecular profile of C. albidus and the high heterogeneity of C. laurentii were kept through the passages in animals. It is concluded that most isolates of both species were recovered from the animal organs after 5 or more days, and phenotypes were not altered by inoculation. No molecular alteration was detected and the virulence factors were not related to the time intervals before isolation from organs.

Characterization of Adherent Umbilical Cord Blood Stromal Cells Regarding Passage, Cell Number, and Nano-biomarking Utilization

Adherent umbilical cord blood stromal cells (AUCBSCs) are multipotent cells with differentiation capacities. Therefore, these cells have been investigated for their potential in cell-based therapies. Quantum Dots (QDs) are an alternative to organic dyes and fluorescent proteins because of their long-term photostability. In this study we determined the effects of the cell passage on AUCBSCs morphology, phenotype, and differentiation potential. QDs labeled AUCBSCs in the fourth cell passage were differentiated in the three mesodermal lineages and were evaluated using cytochemical methods and transmission electron microscopy (TEM). Gene and protein expression of the AUCBSCs immunophenotypic markers were also evaluated in the labeled cells by real-time quantitative PCR and flow cytometry. In this study we were able to define the best cellular passage to work with AUCBSCs and we also demonstrated that the use of fluorescent QDs can be an efficient nano-biotechnological tool in differentiation studies because labeled cells do not have their characteristics compromised.

Prospective randomized trial of EUS versus ERCP-guided common bile duct stone removal: an interim report (with video)

Background: EUS is being increasingly utilized for the diagnosis of choledocholithiasis and microlithiasis, especially in patients with biliary colic. Simultaneously, there is also a rising interest in the use of EUS for therapeutic interventions. Objectives: Our goal was to assess the effectiveness of EUS-directed common bile duct (CBD) stone removal to compare its safety and effectiveness with ERCP-directed intervention. Design: interim results of a prospective, randomized, single-center blinded clinical trial. Setting: A single tertiary care referral center. Patients: Fifty-two patients with uncomplicated CBD stones were prospectively randomized to CBD cannulation and stone removal under EUS or ERCP guidance. Main Outcome Measurements and Interventions: Primary outcome measure was the rate of successful cannulation of the CBD. Secondary Outcome measures included Successful removal of stones and overall complication rates. Results: CBD cannulation followed by stone extraction was successful in 23 of 26 patients (88.5%) in the EUS group (1) versus 25 of 26 patients (96.2%) in the ERCP group (11) (95% CI, -27.65%, 9.88%). Overall, there were 3 complications in the EUS group and 4 complications in the ERCP group. Limitation: The current study is an interim report from a single center report and performed by a single operator. Conclusions: Our preliminary analysis indicates that Outcomes following EUS-guided CBD stone retrieval are equivalent to those following ERCP EUS-related adverse events are similar to those following ERCP. ERCP and EUS-guided stone retrieval appears to be equally effective for therapeutic interventions of the bile duct. Additional studies are required to validate these preliminary results and to determine predictors of success of EUS-guided stone removal. (Gastrointest Endosc 2009;69:238-43.)

Vitamin D Receptor and Calcium-Sensing Receptor Gene Polymorphisms in Hypercalciuric Stone-Forming Patients

Background/Aim: Some studies have identified an association of kidney stone formation with vitamin D receptor (VDR) or calcium-sensing receptor (CaSR) polymorphisms. We aimed to evaluate the association between these polymorphisms with urinary calcium excretion (uCa) in calcium-stone-forming patients. Methods: VDR polymorphism, detected by BsmI digestion, and 3 CaSR polymorphisms (G/T at codon 986, G/A at codon 990 and C/G at codon 1011), detected by direct sequencing, were evaluated in 100 hypercalciuric (HCa) and 101 normocalciuric (NCa) calcium-stone-forming patients. Results: The total allelic frequency of VDR polymorphism was: 16% BB, 49% Bb and 35% bb. The prevalence of bb genotype was significantly higher in the HCa when compared to the NCa group (43 vs. 27%). With respect to CaSR polymorphisms, 986S, 990G and 1011E variant alleles were detected, respectively, in 5, 4 and 3% of the whole sample and 5 CaSR haplotypes were identified: 94% ARQ (wildtype), 3% SRQ, 1.5% AGQ, 1.0% ARE and 0.5% AGE. No statistical differences have been observed between NCa and HCa with respect to these CaSR haplotypes. Conclusions: The present study suggested that bb homozygous for VDR polymorphism was overrepresented in hypercalciuric stone formers. Urinary calcium excretion was not associated with CaSR polymorphism in the present sample. Copyright (C) 2009 S. Karger AG, Basel

Transovarial passage of Leishmania infantum kDNA in artificially infected Rhipicephalus sanguineus

Phlebotomine sand flies are the only proven biological vectors of Leishmania parasites. However, Rhipicephalus sanguineus ticks have long been suspected to transmit Leishmania infantum in studies carried out in laboratory and natural conditions. In the present study, 5 mu l of L. infantum promastigotes (1 x 10(6) cells per ml) was injected into the hemocel through the coxa 1 of four engorged females (F1, F2, F3 and F4). Control ticks (F5 and F6) were injected with sterile phosphate-buffered saline (PBS) using the same procedure. Then, these females, their eggs, and the originated larvae were tested by real time polymerase chain reaction (real-time PCR) for the presence of L. infantum kinetoplast DNA (kDNA). Females and eggs were tested after the end of the oviposition period (about 5 weeks post-inoculation) whereas larvae were tested about 4 months after the inoculation of females. All artificially infected females were positive for L. infantum kDNA. In addition, two pools of eggs (one from F2 and other from F4) and four pools of larvae (one from each F1 and F4 and two from F2) were positive for L infantum kDNA. These results showed, for the first time, the transovarial passage of L. infantum kDNA in R. sanguineus ticks, thus suggesting that the transovarial transmission of L. infantum protozoa in ticks is worth to be investigated. (C) 2010 Elsevier Inc. All rights reserved.

Effects of calcium supplementation on body weight reduction in overweight calcium stone formers

A randomized, placebo-controlled trial was conducted in overweight calcium stone-forming (CSF) patients, to evaluate the effect of calcium supplementation associated with a calorie-restricted diet on body weight (BW) and fat reduction and its potential changes upon serum and urinary parameters. Fifteen patients were placed on a hypocaloric diet for 3 months, supplemented with either calcium carbonate (CaCO(3), n = 8) or placebo (n = 7), 500 mg bid. Blood and 24-h urine samples were collected and body composition was assessed at baseline and after the intervention. At the end of the study, final BW was significantly lower vs baseline in both CaCO(3) (74 +/- A 14 vs. 80 +/- A 14 kg, P = 0.01) and placebo groups (80 +/- A 10 vs. 87 +/- A 9 kg, P = 0.02) but the mean percentage of loss of body weight and body fat did not differ between CaCO(3) and placebo (7.0 +/- A 2.0 vs. 8.0 +/- A 3.0%, P = 0.40 and 13.0 +/- A 7.0 vs. 13.0 +/- A 10.0%; P = 0.81, respectively). After CaCO(3) or placebo, no significant differences versus baseline were observed for urinary parameters in both CaCO(3) and placebo, except for a higher mean urinary citrate in placebo group. These data suggest that increasing calcium intake by calcium carbonate supplementation did not contribute to a further reduction of BW and fat in overweight CSF patients submitted to a hypocaloric diet nor altered urinary lithogenic parameters.

Effect of repeated disinfections by microwave energy on the physical and mechanical properties of denture base acrylic resins

The present study evaluated the effect of repeated simulated microwave disinfection on physical and mechanical properties of Clássico, Onda-Cryl and QC-20 denture base acrylic resins. Aluminum patterns were included in metallic or plastic flasks with dental stone following the traditional packing method. The powder/liquid mixing ratio was established according to the manufacturer's instructions. After water-bath polymerization at 74ºC for 9 h, boiling water for 20 min or microwave energy at 900 W for 10 min, the specimens were deflasked after flask cooling and finished. Each specimen was immersed in 150 mL of distilled water and underwent 5 disinfection cycles in a microwave oven set at 650 W for 3 min. Non-disinfected and disinfected specimens were subjected to the following tets: Knoop hardness test was performed with 25 g load for 10 s, impact strength test was done using the Charpy system with 40 kpcm, and 3-point bending test (flexural strength) was performed at a crosshead speed of 0.5 mm/min until fracture. Data were analyzed statistically by ANOVA and Tukey's test (α= 0.05%). Repeated simulated microwave disinfections decreased the Knoop hardness of Clássico and Onda-Cryl resins and had no effect on the impact strength of QC-20. The flexural strength was similar for all tested resins.

Efeito do número da passagem e do gênero das células doadoras de núcleo no desenvolvimento de bovinos produzidos por transferência nuclear

Objetivou-se com este trabalho avaliar o efeito do número da passagem e do sexo das células doadoras de núcleo no desenvolvimento embrionário e fetal após transferência nuclear. Para isso, oócitos bovinos foram maturados, enucleados e reconstruídos com células somáticas de animal adulto. Após a fusão e ativação química, os zigotos reconstituídos foram cultivados em Charles Rosenkranz 2 (CR2) com monocamada de células da granulosa a 38,8ºC em atmosfera umidificada a 5% de CO2 em ar, durante sete dias, e transferidos para receptoras sincronizadas. As taxas de clivagem e desenvolvimento a blastocisto de embriões reconstruídos com células cultivadas por tempo maior foram inferiores às obtidas com os demais tempos de cultivo. Além disso, os blastocistos produzidos não resultaram no desenvolvimento de uma gestação a termo. Embora a taxa de clivagem em embriões fêmeas tenha sido maior, o número de embriões que atingiram o estádio de blastocisto foi maior nos embriões machos. No período gestacional, fêmeas apresentaram maior taxa de aborto entre 90 e 120 dias de gestação. Esses resultados indicam que células doadoras de núcleos cultivados por longos períodos dificultam a produção de blastocistos e aumentam as chances de perdas durante a gestação. Embriões clonados machos têm maior competência para se desenvolver a blastocisto e resultam em menor taxa de perda gestacional.

Metabolismo mineral em bubalinos com ingestões de diferentes níveis de fósforo

Objetivou-se avaliar os efeitos da ingestão diária de quatro níveis de fósforo (8, 12, 15 e 18 g) sobre o metabolismo de macrominerais (P, Ca, Mg, Na, K e S), incluindo a ingestão, a concentração no rúmen, a taxa de passagem do líquido ruminal, a excreção nas fezes e a disponibilidade aparente. Utilizaram-se quatro bubalinos adultos com fístulas ruminais em delineamento quadrado latino (4 × 4) com dieta total constituída de cana-de-açúcar como volumoso (85%) e concentrado formulado com um dos níveis de fósforo. Os níveis de fósforo não ocasionaram diferença significativa na concentração mineral no rúmen de nenhum mineral estudado. A concentração média de fósforo no conteúdo ruminal foi de 0,98% na matéria seca, enquanto o teor de fósforo nas rações variou de 0,12 a 0,34%, comprovando alta reciclagem de fósforo pela saliva. Níveis crescentes de fósforo na dieta, variando de 8 a 18 g/animal/dia, não influenciam as disponibilidades de cálcio e magnésio. Com o nível de fósforo de 15 g/dia, houve melhor utilização do fósforo da dieta. A ingestão de níveis crescentes de fósforo em g/kg0,75 (X) promoveu aumento linear na excreção fecal desse mineral em g/kg0,75 (Y) e baixos valores de disponibilidade do fósforo, que pode ser estimado pela equação Y = 0,03 + 0,610X, o que indica deficiência desse elemento mineral na dieta para o metabolismo animal.