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PURPOSE: To analyze the functions of the stomatognathic system in children with or without molar-incisor hypomineralization (MIH). METHODS: For this cross-sectional study, 72 children aged 6-12 years were recruited and divided in two groups: with MIH (G1) and without MIH (G2). T-SCAN was used to verify the distribution of occlusal contacts, gnathodynamometer to measure maximum molar bite force, and Iowa Oral Pressure Instrument (IOPI) to assess the strength of facial expression muscles. The t test and paired t test (p ≤ 0.05) were used for statistical comparisons. RESULTS: The molars affected by MIH exhibited lower distribution of occlusal forces (p < 0.001) and lower maximum molar bite force (p < 0.05) compared to the molars in the control group. However, there was no difference between the MIH-affected sides compared to the unaffected side, nor between the molars affected by MIH and their antagonists (p > 0.05). There were no differences in the forces of the facial expression muscles between the groups. CONCLUSIONS: These findings suggest that MIH significantly impacts occlusal force distribution and bite force, but not facial expression musculature.

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The aromatic nucleophilic substitution reactions of the nitro group of 4-Nitro-N-alkyl-1,8-naphthalimides by thiolate anions produce fluorescent derivatives and their rates are strongly accelerated by micelles of hexadecyltrimethylammonium chloride even at low pH. Acceleration factors of this reactions can reach million-fold. As the products are oxidant-insensible, this reaction allows the determination of SH- containing compounds such as cysteine, glutathione or proteins even in oxidative conditions. Limits of detection are as low as 5 × 10-7 M, ten times lower than the limit for the classic 5,5'-dithiobis-(2-nitrobenzoic) acid method. Moreover, this reaction can be developed at pHs between 6.5 and 7.5 thereby diminishing the rate of spontaneous oxidation of the thiols. In addition, we demonstrated that 4-Nitro-N-alkyl-1,8-naphthalimides can be used to evidence SH groups in peptides, proteins and living cells.

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Conductance was measured in two different double stranded DNA (both with 20 bases), the more conducting poly(dG)-poly(dC) (ds-DNAc) and the less conducting poly(dA)-poly(dT) (ds-DNAi), by means of Electrochemical Capacitance Spectroscopy (ECS). The use of the ECS approach, exemplified herein with DNA nanowires, is equally a suitable and time-dependent advantageous alternative for conductance measurement of molecular systems, additionally allowing better understanding of the alignment existing between molecular scale conductance and electron transfer rate.

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AIM: To evaluate the effectiveness of Reciproc for the removal of cultivable bacteria and endotoxins from root canals in comparison with multifile rotary systems. METHODOLOGY: The root canals of forty human single-rooted mandibular pre-molars were contaminated with an Escherichia coli suspension for 21 days and randomly assigned to four groups according to the instrumentation system: GI - Reciproc (VDW); GII - Mtwo (VDW); GIII - ProTaper Universal (Dentsply Maillefer); and GIV -FKG Race(™) (FKG Dentaire) (n = 10 per group). Bacterial and endotoxin samples were taken with a sterile/apyrogenic paper point before (s1) and after instrumentation (s2). Culture techniques determined the colony-forming units (CFU) and the Limulus Amebocyte Lysate assay was used for endotoxin quantification. Results were submitted to paired t-test and anova. RESULTS: At s1, bacteria and endotoxins were recovered in 100% of the root canals investigated (40/40). After instrumentation, all systems were associated with a highly significant reduction of the bacterial load and endotoxin levels, respectively: GI - Reciproc (99.34% and 91.69%); GII - Mtwo (99.86% and 83.11%); GIII - ProTaper (99.93% and 78.56%) and GIV - FKG Race(™) (99.99% and 82.52%) (P < 0.001). No statistical difference were found amongst the instrumentation systems regarding bacteria and endotoxin removal (P > 0.01). CONCLUSION: The reciprocating single file, Reciproc, was as effective as the multifile rotary systems for the removal of bacteria and endotoxins from root canals.

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Partial or complete edentulism impairs mastication. However, it is unclear how the chewing cycle is affected by prosthetics. We evaluated the chewing movements of patients fitted with complete (CD) or removable partial denture (RPD). A total of 29 subjects were kinesiographically evaluated during chewing of peanuts and Optocal portions in a random sequence. The subjects were divided into two groups according to prosthesis type. Group RPD was composed of 14 partially edentulous patients using a lower distal extension RPD (mean age 61 ± 8 years), and group CD contained 15 completely edentulous patients using CD (mean age 65·9 ± 7·9 years) in both jaws. Opening, closing, occlusal and masticatory cycle times, movement angle (opening and closing), maximum velocity (opening and closing), total area and chewing cycle amplitudes were evaluated. The results were subjected to anova and Tukey's HSD test at a significance level of 5%. The RPD group exhibited shorter opening and closing phases and masticatory cycle time (P < 0·05). Maximum velocities were also higher in the RPD group, irrespective of the test material (P < 0·05). The area and amplitude of the chewing envelope was smaller in the CD group (P < 0·0001). The test material did not influence chewing cycles in any of the parameters evaluated (P > 0·05). RPD wearers use a faster chewing sequence with greater vertical and lateral jaw excursions compared with CD wearers.

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Denture liners (DL) are easily colonized by Candida spp. In an attempt to prevent biofilm colonization, manufacturers have incorporated undecylenic acid (UDA) into DL. In this in vitro study, the effects of UDA released from DL on Candida biofilms were investigated. The concentrations of UDA released from commercial DL were determined by gas chromatography-mass spectrometry (GC-MS). Minimum inhibitory concentration (MIC) and minimum fungistatic concentration (MFC) tests were performed for C. albicans or C. glabrata, with UDA for comparison with the concentrations released from DL. Specimens of DL with (experimental group) and without UDA (control group) were fabricated, and Candida biofilms were developed on DL surfaces. Biofilms were evaluated by cell counts, metabolic activity, structure, and secretion of proteinase or phospholipase. The concentrations of UDA released were within the MIC and MFC ranges. In the presence of UDA, C. albicans biofilms were thinner and had lower numbers of viable and active cells, although no significant enzymatic changes were observed relative to the control group (p > 0.05). In contrast, C. glabrata biofilms exhibited higher cell counts and greater metabolic activity and also increased proteinase activity in the presence of UDA relative to the control group (p < 0.05). Overall, UDA did not prevent Candida biofilm formation.

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Foram avaliadas oito gatas com piometra por meio de anamnese, exame clínico (temperatura, frequência cardíaca e respiratória, coloração das mucosas) e laboratorial (hemograma e bioquímica sérica), antes e após ovário-histerectomia. Os sinais clínicos mais comuns foram apatia e corrimento vaginal, característicos de piometra de cérvix aberta. Ocorreu leucocitose por neutrofilia e trombocitopenia em cinco gatas no pré-operatório. Os índices de ureia estavam aumentados no pré-operatório, assim permanecendo após a cirurgia. Em gatas com piometra, a anamnese é fundamental, bem como o exame clínico e o laboratorial, permitindo o diagnóstico precoce para estabelecimento da conduta terapêutica, que é curativa. A demora na procura por atendimento leva a prognóstico reservado e evidencia a necessidade de trabalho educativo junto aos proprietários. Essas medidas adotadas em conjunto melhoram o prognóstico e diminuem a mortalidade.

Eight queens with pyometra were assessed by clinical examination (temperature, heart rate and respiratory rate, mucous membrane color), and laboratory (blood count and serum biochemistry) before and after ovaryhisterectomy. The most common clinical signs were apathy and vaginal discharge, characteristic of open pyometra. There was a neutrophilic leukocytosis and thrombocytopenia in five cats preoperatively. The urea rates were elevated preoperatively and remained after surgery. In cats with pyometra anamnesis is essential, as well as clinical and laboratory examination, to allow early establishment of the therapeutic, which is curative. The delay in seeking treatment leads to poor prognosis and highlights the need for educational work with the owners. These measures taken together improve prognosis and reduce mortality.

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Foram avaliadas oito gatas com piometra por meio de anamnese, exame clínico (temperatura, frequência cardíaca e respiratória, coloração das mucosas) e laboratorial (hemograma e bioquímica sérica), antes e após ovário-histerectomia. Os sinais clínicos mais comuns foram apatia e corrimento vaginal, característicos de piometra de cérvix aberta. Ocorreu leucocitose por neutrofilia e trombocitopenia em cinco gatas no pré-operatório. Os índices de ureia estavam aumentados no pré-operatório, assim permanecendo após a cirurgia. Em gatas com piometra, a anamnese é fundamental, bem como o exame clínico e o laboratorial, permitindo o diagnóstico precoce para estabelecimento da conduta terapêutica, que é curativa. A demora na procura por atendimento leva a prognóstico reservado e evidencia a necessidade de trabalho educativo junto aos proprietários. Essas medidas adotadas em conjunto melhoram o prognóstico e diminuem a mortalidade.

Eight queens with pyometra were assessed by clinical examination (temperature, heart rate and respiratory rate, mucous membrane color), and laboratory (blood count and serum biochemistry) before and after ovaryhisterectomy. The most common clinical signs were apathy and vaginal discharge, characteristic of open pyometra. There was a neutrophilic leukocytosis and thrombocytopenia in five cats preoperatively. The urea rates were elevated preoperatively and remained after surgery. In cats with pyometra anamnesis is essential, as well as clinical and laboratory examination, to allow early establishment of the therapeutic, which is curative. The delay in seeking treatment leads to poor prognosis and highlights the need for educational work with the owners. These measures taken together improve prognosis and reduce mortality.(AU)

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The manner by which effects of simultaneous mutations combine to change enzymatic activity is not easily predictable because these effects are not always additive in a linear manner. Hence, the characterization of the effects of simultaneous mutations of amino acid residues that bind the substrate can make a significant contribution to the understanding of the substrate specificity of enzymes. In the â-glycosidase from Spodoptera frugiperda (Sfâgly), both residues Q39 and E451 interact with the substrate and this is essential for defining substrate specificity. Double mutants of Sfâgly (A451E39, S451E39 and S451N39) were prepared by site-directed mutagenesis, expressed in bacteria and purified using affinity chromatography. These enzymes were characterized using p-nitrophenyl â-galactoside and p-nitrophenyl â-fucoside as substrates. The k cat/Km ratio for single and double mutants of Sfâgly containing site-directed mutations at positions Q39 and E451 was used to demonstrate that the effect on the free energy of ES‡ (enzyme-transition state complex) of the double mutations (∆∆G‡xy) is not the sum of the effects resulting from the single mutations (∆∆G‡x and ∆∆G‡y). This difference in ∆∆G‡ indicates that the effects of the single mutations partially overlap. Hence, this common effect counts only once in ∆∆G‡xy. Crystallographic data on â-glycosidases reveal the presence of a bidentate hydrogen bond involving residues Q39 and E451 and the same hydroxyl group of the substrate. Therefore, both thermodynamic and crystallographic data suggest that residues Q39 and E451 exert a mutual influence on their respective interactions with the substrate.

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The manner by which effects of simultaneous mutations combine to change enzymatic activity is not easily predictable because these effects are not always additive in a linear manner. Hence, the characterization of the effects of simultaneous mutations of amino acid residues that bind the substrate can make a significant contribution to the understanding of the substrate specificity of enzymes. In the beta-glycosidase from Spodoptera frugiperda (Sfbetagly), both residues Q39 and E451 interact with the substrate and this is essential for defining substrate specificity. Double mutants of Sfbetagly (A451E39, S451E39 and S451N39) were prepared by site-directed mutagenesis, expressed in bacteria and purified using affinity chromatography. These enzymes were characterized using p-nitrophenyl beta-galactoside and p-nitrophenyl beta-fucoside as substrates. The k cat/Km ratio for single and double mutants of Sfbetagly containing site-directed mutations at positions Q39 and E451 was used to demonstrate that the effect on the free energy of ESdouble dagger (enzyme-transition state complex) of the double mutations (Gdouble daggerxy) is not the sum of the effects resulting from the single mutations (Gdouble daggerx and Gdouble daggery). This difference in Gdouble dagger indicates that the effects of the single mutations partially overlap. Hence, this common effect counts only once in Gdouble daggerxy. Crystallographic data on beta-glycosidases reveal the presence of a bidentate hydrogen bond involving residues Q39 and E451 and the same hydroxyl group of the substrate. Therefore, both thermodynamic and crystallographic data suggest that residues Q39 and E451 exert a mutual influence on their respective interactions with the substrate.

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Cocona (Solanum sessiliflorum Dunal) is a solanaceous shrub native to the Amazon region that produces an edible fruit. This species has numerous advantages, particularly a high nutritional value and productivity. However, due to irregular germination and rapid loss of seed viability, there are few plantations for production on a large scale. Development of alternative propagation strategies is essential for the production of homogeneous seedlings of genotypes with superior agronomic performance. We developed techniques for in vitro regeneration of the cocona varieties Santa Luzia and Thaís for large-scale production of healthy plantlets. Twenty days after seeding, seedling segments germinated in vitro were used as explant sources. Three successive experiments were performed: one to test the effect of the explant source and combinations of two growth regulators, auxin (indole acetic acid, IAA) and kinetin (KIN), on the morphogenetic response; another to investigate the effect of the combination of growth regulators on the morphogenetic response of hypocotyl segments, and another to evaluate how sucrose concentration affects the development of adventitious shoots. The best shoot induction was obtained using hypocotyl segments and stem apices, while rhizogenesis was greatest in leaves with a petiole. The number of adventitious shoots per explant on hypocotyl segments increased with 10 and 20 mg/L KIN, combined with 0.02 mg/L IAA in the variety Santa Luzia. Sucrose combined with these growth regulator levels increased the average number of calli; these were optimally produced when 45 g/L sucrose and 0.01 mg/L IAA + 20 mg/L KIN were applied. Only sucrose concentration influenced shoot proliferation in the two S. sessiliflorum varieties, with a maximum at 17.5 g/L.

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The synchrotron radiation total reflection X-ray fluorescence (SRTXRF) technique was used for the analysis of heavy metals in produced water samples from oil field in Rio Grande do Norte, in order to determine potential sources of pollution. Since the inorganic components in produced water generally resembling sea water, pre-concentration procedures have been applied to increase the concentration of the analyte of interest and to minimize the salt matrix effects. This technique allows us to determine the contents of V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Hg and Pb in 20 produced water samples. The great majority of the sampling points presented low elemental concentration value. However, in some sample, the Fe, Ni, Cu, Zn and Hg concentration were higher than the established limits by the Brazilian legislation.

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beta 2-Glycoprotein I (beta 2 GPI) is known to influence macrophage uptake of particles with phosphatidylserine containing surfaces, as apoptotic thymocytes and unilamellar vesicles in vitro. Nevertheless, effects upon macrophage activation induced by this interaction are still unknown. beta 2 GPI influence upon the reactive species production by Kupffer cells was evaluated in order to investigate whether beta 2 GPI modulates the macrophage response to negatively charged surfaces. Chemiluminescence of isolated non-parenchymal rat liver cells was measured after phagocytosis of opsonized zymosan or phorbolymristate acetate (PMA) stimulation, in the presence and absence of large unilamellar vesicles (LUVs) containing 25 mol% phosphatidylserine (PS) or 50 mol% cardiolipin (CL) and complementary molar ratio of phosphatidylcholine (PC). beta 2 GPI decreased by 50% the chemiluminescence response induced by opsonized zymosan, with a 66% reduction of the initial light emission rate. PMA stimulated Kupffer cell chemiluminescence was insensitive to human or rat beta 2 GPI. Albumin (500 micrograms/ml) showed no effect upon chemiluminescence. beta 2 GPI increased PS/PC LUV uptake and degradation by Kupffer cells in a concentration-dependent manner, without leakage of the internal contents of the LUVs, as shown by fluorescence intensity enhancement. LUVs opsonized with antiphospholipid antibodies (aPL) from syphilitic patients increased light emission by Kupffer cells. Addition of beta 2 GPI to the assay reduced chemiluminescence due to opsonization with purified IgG antibodies from systemic lupus erythematosus (SLE or syphilis (Sy) patient sera. A marked net increase in chemiluminescence is observed in the presence of Sy aPL antibodies, whereas a decrease was found when SLE aPL were added to the assay, in the presence or absence of beta 2 GPI. At a concentration of 125 micrograms/ml, beta 2 GPI significantly reduced Kupffer cell Candida albicans phagocytosis index and killing score by 50 and 10%, respectively. The present data strongly suggest that particle uptake in the presence of beta 2 GPI is coupled to an inhibition of reactive species production by liver macrophages during the respiratory burst, supporting the role of beta 2 GPI as a mediator of senescent cell removal.

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Leguminous trees are being suggested for revegetation programs due to their ability to develop associations with rhizobia and mycorrhizal fungi. The growth of a native species of the Tropical Atlantic Forest, Centrolobium tomentosum, was evaluated in a native forest soil and in a Eucalyptus forest soil under different treatments of inoculation. C. tomentosum produced more biomass under nursery conditions after inoculation with Rhizobium BHICB-Ab1 associated with arbuscular mycorrhizal (AM). This treatment improved shoot and root growth and nodule weight under forest soil condition, while in eucalyptus soil only shoot biomass and nodule weight were significantly modified. In another experiment, using forest soil, height and stem diameter were also increased by dual inoculation procedures. The height and diameter growth promoting effect was observed when BHICB-Ab1 was used as inoculant associated with AM, but not with BHICB-Ab1 alone. In contrast, plants inoculated with BHICB-Ab3 alone were similar in height and diameter growth, to those which were inoculated with BHICB-Ab3 associated with AM. These results suggest that benefits of dual inoculation depend on triparty symbiosis and especially on the choice of Rhizobium strain.

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In order to know the distributional patterns of Basommatophoran snails in the state of São Paulo (Brazil), 85 "counties" in the area of S. José do Rio Preto were worked out during seven months (1982). Snails from 286 breeding places were collected and identified. Biomphalaria straminea, an intermediate host of S. mansoni, was found in four little ponds, in the neighbourhood of Altair and S. José do Rio Preto. It was concluded that schistosomiasis has little chance to spread out in the studied area.

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Specimens of Biomphalaria occidentialis and Biomphalaria tenagophila were reared in S. Paulo, Brazil under laboratory conditions, with a view to know their biological characteristics. Oviposition and eggs/oviposition ratio were recorded over twelve months so as to obtain information on the number of egg-masses per animal and the number of eggs per egg-mass, as also the number of hatched eggs per egg-mass for each period of 30 days, i.e., the hatching-rate per period. The incubation period was about the same for both species, but the oviposition and egg oviposition ratio were greater in B. tenagophila.

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The study's purpose was to evaluate the reduction of dental caries incidence by the association of two preventive methods. 246 students of both sexes aged from 7 to 11 years registered in "Escola de Educação Básica da Universidade Federal de Uberlândia" and living in the urbana area of Uberlândia, state of Minas Gerais, were examined. The sample was distributed into two groups: children from Group 1, which received a semestral topical application of Acidulated Fluor Phosphate at 1.23% and children from Group II, that besides the topical application above related (Group I) also received weekly mouthwashes of sodium fluoride aquesus solution at 0.2%. After two years of study DMFS index were tabled and statistically analysed. It was verified a reduction of 33.97% in the incidence of dental caries (in the permanent dentition). The difference between the Groups was significant at 5% level of confidence.

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