50 resultados para "ought implies can"maxim.

em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo (BDPI/USP)


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This study aimed to evaluate the effects of a flavor-containing dentifrice on the formation of volatile sulphur compounds (VSCs) in morning bad breath. A two-step, blinded, crossover, randomized study was carried out in 50 dental students with a healthy periodontium divided into two experimental groups: flavor-containing dentifrice (test) and non-flavor-containing dentifrice (control). The volunteers received the designated dentifrice and a new toothbrush for a 3 X/day brushing regimen for 2 periods of 30 days. A seven-day washout interval was used between the periods. The assessed parameters were: plaque index (PI), gingival index (GI), organoleptic breath scores (ORG), VSC levels (as measured by a portable sulphide monitor) before (H1) and after (H2) cleaning of the tongue, tongue coating (TC) wet weight and BANA test from TC samples. The intra-group analysis showed a decrease in ORG, from 3 to 2, after 30 days for the test group (p < 0.05). The inter-group analysis showed lower values in ORG, H1 and H2 for the test group (p < 0.05). There was no difference between the amount of TC between groups and the presence of flavor also did not interfere in the BANA results between groups (p > 0.05). These findings suggest that a flavor-containing dentifrice seems to prevent VSCs formation in morning bad breath regardless of the amount of TC in periodontally healthy subjects.

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Because a greater research effort has been directed to analyzing the adhesive effectiveness of self etch primers to dentin, the aim of this study was to evaluate, by microtensile testing, the bond strength to enamel of a composite resin combined with a conventional adhesive system or with a self-etching primer adhesive, used according to its original prescription or used with previous acid etching. Thirty bovine teeth were divided into 3 groups with 10 teeth each (n= 10). In one of the groups, a self-etching primer (Clearfil SE Bond - Kuraray) was applied in accordance with the manufacturer's instructions and, in the other, it was applied after previous acid etching. In the third group, a conventional adhesive system (Scotchbond Multipurpose Plus - 3M-ESPE) was applied in accordance with the manufacturer's instructions. The results obtained by analysis of variance revealed significant differences between the adhesive systems (F = 22.31). The self-etching primer (Clearfil SE Bond) presented lower enamel bond strength values than the conventional adhesive system (Scotchbond Multipurpose Plus) (m = 39.70 ± 7.07 MPa) both when used according to the original prescription (m = 27.81 ± 2.64 MPa) and with previous acid etching (m = 25.08 ± 4.92 MPa).

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Inicia-se uma discussão sobre as práticas de saúde e cuidado utilizadas pelos Kaiowá e Guarani da Terra Indígena de Caarapó no enfrentamento das doenças diarréicas na infância. Utilizou-se de uma contribuição etnográfica, através do uso da técnica da observação participante e de entrevistas aberta com moradores da comunidade. Em se tratando de uma sociedade que vivencia permanentes transformações de ordem social advindas das relações interétnicas e da sucessiva presença dos serviços de saúde, observa-se que o significado de diarréia infantil, assim como as decisões relativas à prevenção e ao seu tratamento, refletem comportamentos diferenciados e complexos. A diarréia, também conhecida como chiri, é definida através de sinais que, de certa forma, são semelhantes aos biomédicos. No entanto, nem sempre as explicações de causalidade e as formas de tratamento seguem, unicamente, a abordagem biomédica. A variedade de causas da doença diarréica entre as crianças indígenas implica na escolha do processo terapêutico, que pode ser desde a procura por um especialista tradicional, realização de chás e infusões e, ainda, procura pelos serviços de saúde. Tais explicações e formas de tratamento pressupõem a existência de um processo de negociação entre pessoas de uma mesma cultura e de culturas distintas. Neste sentido, os serviços de saúde ao tratar a criança com diarréia, devem considerar não apenas a perspectiva biomédica, mas também dialogar com a percepção e as práticas indígenas na identificação da causalidade, na definição do diagnóstico e do tratamento, sobretudo, pela coexistência destas práticas no contexto local

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Background: Although clinical diabetes mellitus is obviously a high risk factor for myocardial infarction (MI), in experimental studies disagreement exists about the sensitivity to ischemic injury of an infarcted myocardium. Recently, our group demonstrated that diabetic animals presented better cardiac function recovery and cellular resistance to ischemic injury than nondiabetics. In the present study, we evaluated the chronic effects of MI on left ventricular (LV) and autonomic functions in streptozotocin (STZ) diabetic rats. Methods: Male Wistar rats were divided into 4 groups: control (C, n = 15), diabetes (D, n = 16), MI (I, n = 21), and diabetes + MI (DI, n = 30). MI was induced 15 days after diabetes (STZ) induction. Ninety days after MI, LV and autonomic functions were evaluated (8 animals each group). Left ventricular homogenates were analyzed by Western blotting to evaluate the expression of calcium handling proteins. Results: MI area was similar in infarcted groups (similar to 43%). Ejection fraction and + dP/dt were reduced in I compared with DI. End-diastolic pressure was additionally increased in I compared with DI. Compared with DI, I had increased Na(+)-Ca(2+) exchange and phospholamban expression (164%) and decreased phosphorylated phospholamban at serine(16) (65%) and threonine(17) (70%) expression. Nevertheless, diabetic groups had greater autonomic dysfunction, observed by baroreflex sensitivity and pulse interval variability reductions. Consequently, the mortality rate was increased in DI compared with I, D, and C groups. Conclusions: LV dysfunction in diabetic animals was attenuated after 90 days of myocardial infarction and was associated with a better profile of calcium handling proteins. However, this positive adaptation was not able to reduce the mortality rate of DI animals, suggesting that autonomic dysfunction is associated with increased mortality in this group. Therefore, it is possible that the better cardiac function has been transitory, and the autonomic dysfunction, more prominent in diabetic group, may lead, in the future, to the cardiovascular damage.

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Background: Children born small for gestational age (SGA) experience higher rates of morbidity and mortality than those born appropriate for gestational age. In Latin America, identification and optimal management of children born SGA is a critical issue. Leading experts in pediatric endocrinology throughout Latin America established working groups in order to discuss key challenges regarding the evaluation and management of children born SGA and ultimately develop a consensus statement. Discussion: SGA is defined as a birth weight and/or birth length greater than 2 standard deviations (SD) below the population reference mean for gestational age. SGA refers to body size and implies length-weight reference data in a geographical population whose ethnicity is known and specific to this group. Ideally, each country/region within Latin America should establish its own standards and make relevant updates. SGA children should be evaluated with standardized measures by trained personnel every 3 months during year 1 and every 6 months during year 2. Those without catch-up growth within the first 6 months of life need further evaluation, as do children whose weight is <= -2 SD at age 2 years. Growth hormone treatment can begin in SGA children > 2 years with short stature (< -2.0 SD) and a growth velocity < 25th percentile for their age, and should continue until final height (a growth velocity below 2 cm/year or a bone age of > 14 years for girls and > 16 years for boys) is reached. Blood glucose, thyroid function, HbA1c, and insulin-like growth factor-1 (IGF-1) should be monitored once a year. Monitoring insulin changes from baseline and surrogates of insulin sensitivity is essential. Reduced fetal growth followed by excessive postnatal catch-up in height, and particularly in weight, should be closely monitored. In both sexes, gonadal function should be monitored especially during puberty. Summary: Children born SGA should be carefully followed by a multidisciplinary group that includes perinatologists, pediatricians, nutritionists, and pediatric endocrinologists since 10% to 15% will continue to have weight and height deficiency through development and may benefit from growth hormone treatment. Standards/guidelines should be developed on a country/region basis throughout Latin America.

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Background Minimal residual disease is an important independent prognostic factor in childhood acute lymphoblastic leukemia. The classical detection methods such as multiparameter flow cytometry and real-time quantitative polymerase chain reaction analysis are expensive, time-consuming and complex, and require considerable technical expertise. Design and Methods We analyzed 229 consecutive children with acute lymphoblastic leukemia treated according to the GBTLI-99 protocol at three different Brazilian centers. Minimal residual disease was analyzed in bone marrow samples at diagnosis and on days 14 and 28 by conventional homo/heteroduplex polymerase chain reaction using a simplified approach with consensus primers for IG and TCR gene rearrangements. Results At least one marker was detected by polymerase chain reaction in 96.4%, of the patients. By combining the minimal residual disease results obtained on days 14 and 28, three different prognostic groups were identified: minimal residual disease negative on days 14 and 28, positive on day 14/negative on day 28, and positive on both. Five-year event-free survival rates were 85%, 75.6%,, and 27.8%, respectively (p<0.0001). The same pattern of stratification held true for the group of intensively treated children. When analyzed in other subgroups of patients such as those at standard and high risk at diagnosis, those with positive B-derived CD10, patients positive for the TEL/AML1 transcript, and patients in morphological remission on a day 28 marrow, the event-free survival rate was found to be significantly lower in patients with positive minimal residual disease on day 28. Multivariate analysis demonstrated that the detection of minimal residual disease on day 28 is the most significant prognostic factor. Conclusions This simplified strategy for detection of minimal residual disease was feasible, reproducible, cheaper and simpler when compared with other methods, and allowed powerful discrimination between children with acute lymphoblastic leukemia with a good and poor outcome.

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Background Data and Objective: Herpes is a common infectious disease that is caused by human herpesviruses. Several treatments have been proposed, but none of them prevent reactivation of the virus. This article describes the use of photodynamic therapy (PDT) as a treatment for herpes lesions, and reports on four cases. Materials and Methods: PDT was used as an adjuvant therapy for the treatment of herpes labialis in four patients. A special type of 0.01% (m/V) of methylene blue solution was applied to the vesicular stage of herpesviral disease and the lesions were irradiated with laser energy (wavelength 660 nm, energy density 120 J/cm(2), output power of 40 mW, 2 min per point, 4.8 J of energy/point, at four points). After 24 h the patients returned and phototherapy was repeated with the same equipment, this time with 3.8 J/cm(2) and 15 mW, for a total dose of 0.6 J. The same procedure was repeated 72 h and 1 wk later. Results: Treatment with low-level laser therapy can be considered as an option in the treatment of herpes labialis, and decreases the frequency of vesicle recurrence and provides comfort for patients. No significant acute side effects were noted and the lesions healed rapidly. Conclusion: Treatment of herpes labialis with PDT was effective, had no side effects, and when associated with laser phototherapy, accelerated the healing process.

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Background: Despite the importance of collecting individual data of socioeconomic status (SES) in epidemiological oral health surveys with children, this procedure relies on the parents as respondents. Therefore, type of school (public or private schools) could be used as an alternative indicator of SES, instead of collecting data individually. The aim of this study was to evaluate the use of the variable type of school as an indicator of socioeconomic status as a substitute of individual data in an epidemiological survey about dental caries in Brazilian preschool children. Methods: This study followed a cross-sectional design, with a random sample of 411 preschool children aged 1 to 5 years, representative of Catalao, Brazil. A calibrated examiner evaluated the prevalence of dental caries and parents or guardians provided information about several individual socioeconomic indicators by means of a semi-structured questionnaire. A multilevel approach was used to investigate the association among individual socioeconomic variables, as well as the type of school, and the outcome. Results: When all significant variables in the univariate analysis were used in the multiple model, only mother's schooling and household income (individual socioeconomic variables) presented significant associations with presence of dental caries, and the type of school was not significantly associated. However, when the type of school was used alone, children of public school presented significantly higher prevalence of dental caries than those enrolled in private schools. Conclusions: The type of school used as an alternative indicator for socioeconomic status is a feasible predictor for caries experience in epidemiological dental caries studies involving preschool children in Brazilian context.

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Papillomaviruses have been reported to be very difficult to grow in cell culture. Also, there are no descriptions of cell cultures from lesions of bovine cutaneous papillomatosis, with identification of different bovine papilloma virus (BPV) DNA sequences. In the present report, we describe primary cell cultures from samples of cutaneous lesions (warts). We investigated the simultaneous presence of different BPV DNA sequences, comparing the original lesion to different passages of the cell cultures and to peripheral blood. BPV 1, 2 and 4 DNA sequences were found in lesion samples, and respective cell cultures and peripheral blood, supporting our previous hypothesis of the possible activity of these sequences in different samples and now also showing how they can be maintained in different passages of cell cultures.

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A new age-redshift test is proposed in order to constrain H(0) on the basis of the existence of old high-redshift galaxies (OHRGs). In the flat Lambda cold dark matter model, the value of H(0) is heavily dependent on the mass density parameter Omega(M) = 1- Omega(Lambda). Such a degeneracy can be broken through a joint analysis involving the OHRG and baryon acoustic oscillation signature. By assuming a galaxy incubation time, t(inc) = 0.8 +/- 0.4 Gyr, our joint analysis yields a value of H(0) = 71 +/- 4 km s(-1) Mpc(-1) (1 sigma) with the best-fit density parameter Omega(M) = 0.27 +/- 0.03. Such results are in good agreement with independent studies from the Hubble Space Telescope key project and recent estimates of the Wilkinson Microwave Anisotropy Probe, thereby suggesting that the combination of these two independent phenomena provides an interesting method to constrain the Hubble constant.

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Context. Classical Be stars are rapid rotators of spectral type late O to early A and luminosity class V-III, which exhibit Balmer emission lines and often a near infrared excess originating in an equatorially concentrated circumstellar envelope, both produced by sporadic mass ejection episodes. The causes of the abnormal mass loss (the so-called Be phenomenon) are as yet unknown. Aims. For the first time, we can now study in detail Be stars outside the Earth's atmosphere with sufficient temporal resolution. We investigate the variability of the Be Star CoRoT-ID 102761769 observed with the CoRoT satellite in the exoplanet field during the initial run. Methods. One low-resolution spectrum of the star was obtained with the INT telescope at the Observatorio del Roque de los Muchachos. A time series analysis was performed using both cleanest and singular spectrum analysis algorithms to the CoRoT light curve. To identify the pulsation modes of the observed frequencies, we computed a set of models representative of CoRoT-ID 102761769 by varying its main physical parameters inside the uncertainties discussed. Results. We found two close frequencies related to the star. They are 2.465 c d(-1) (28.5 mu Hz) and 2.441 c d(-1) (28.2 mu Hz). The precision to which those frequencies were found is 0.018 c d(-1) (0.2 mu Hz). The projected stellar rotation was estimated to be 120 km s(-1) from the Fourier transform of spectral lines. If CoRoT-ID 102761769 is a typical Galactic Be star it rotates near the critical velocity. The critical rotation frequency of a typical B5-6 star is about 3.5 c d(-1) (40.5 mu Hz), which implies that the above frequencies are really caused by stellar pulsations rather than star's rotation.

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Context. TWA22 was initially regarded as a member of the TW Hydrae association (TWA). In addition to being one of the youngest (approximate to 8 Myr) and nearest (approximate to 20 pc) stars to Earth, TWA22 has proven to be very interesting after being resolved as a tight, very low-mass binary. This binary can serve as a very useful dynamical calibrator for pre-main sequence evolutionary models. However, its membership in the TWA has been recently questioned despite due to the lack of accurate kinematic measurements. Aims. Based on proper motion, radial velocity, and trigonometric parallax measurements, we aim here to re-analyze the membership of TWA22 to young, nearby associations. Methods. Using the ESO NTT/SUSI2 telescope, we observed TWA22 AB during 5 different observing runs over 1.2 years to measure its trigonometric parallax and proper motion. This is a part of a larger project measuring trigonometric parallaxes and proper motions of most known TWA members at a sub-milliarcsec level. HARPS at the ESO 3.6 m telescope was also used to measure the system's radial velocity over 2 years. Results. We report an absolute trigonometric parallax of TWA22 AB, pi = 57.0 +/- 0.7 mas, corresponding to a distance 17.5 +/- 0.2 pc from Earth. Measured proper motions of TWA 22AB are mu(alpha) cos(delta) = -175.8 +/- 0.8 mas/yr and mu delta = -21.3 +/- 0.8 mas/yr. Finally, from HARPS measurements, we obtain a radial velocity V(rad) = 14.8 +/- 2.1 km s(-1). Conclusions. A kinematic analysis of TWA22 AB space motion and position implies that a membership of TWA22 AB to known young, nearby associations can be excluded except for the beta Pictoris and TW Hydrae associations. Membership probabilities based on the system's Galactic space motion and/or the trace-back technique support a higher chance of being a member to the beta Pictoris association. Membership of TWA22 in the TWA cannot be fully excluded because of large uncertainties in parallax measurements and radial velocities and to the uncertain internal velocity dispersion of its members.

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The VISTA near infrared survey of the Magellanic System (VMC) will provide deep YJK(s) photometry reaching stars in the oldest turn-off point throughout the Magellanic Clouds (MCs). As part of the preparation for the survey, we aim to access the accuracy in the star formation history (SFH) that can be expected from VMC data, in particular for the Large Magellanic Cloud (LMC). To this aim, we first simulate VMC images containing not only the LMC stellar populations but also the foreground Milky Way (MW) stars and background galaxies. The simulations cover the whole range of density of LMC field stars. We then perform aperture photometry over these simulated images, access the expected levels of photometric errors and incompleteness, and apply the classical technique of SFH-recovery based on the reconstruction of colour-magnitude diagrams (CMD) via the minimisation of a chi-squared-like statistics. We verify that the foreground MW stars are accurately recovered by the minimisation algorithms, whereas the background galaxies can be largely eliminated from the CMD analysis due to their particular colours and morphologies. We then evaluate the expected errors in the recovered star formation rate as a function of stellar age, SFR(t), starting from models with a known age-metallicity relation (AMR). It turns out that, for a given sky area, the random errors for ages older than similar to 0.4 Gyr seem to be independent of the crowding. This can be explained by a counterbalancing effect between the loss of stars from a decrease in the completeness and the gain of stars from an increase in the stellar density. For a spatial resolution of similar to 0.1 deg(2), the random errors in SFR(t) will be below 20% for this wide range of ages. On the other hand, due to the lower stellar statistics for stars younger than similar to 0.4 Gyr, the outer LMC regions will require larger areas to achieve the same level of accuracy in the SFR( t). If we consider the AMR as unknown, the SFH-recovery algorithm is able to accurately recover the input AMR, at the price of an increase of random errors in the SFR(t) by a factor of about 2.5. Experiments of SFH-recovery performed for varying distance modulus and reddening indicate that these parameters can be determined with (relative) accuracies of Delta(m-M)(0) similar to 0.02 mag and Delta E(B-V) similar to 0.01 mag, for each individual field over the LMC. The propagation of these errors in the SFR(t) implies systematic errors below 30%. This level of accuracy in the SFR(t) can reveal significant imprints in the dynamical evolution of this unique and nearby stellar system, as well as possible signatures of the past interaction between the MCs and the MW.

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We analyze the interaction between dark energy and dark matter from a thermodynamical perspective. By assuming they have different temperatures, we study the possibility of occurring a decay from dark matter into dark energy, characterized by a negative parameter Q. We find that, if at least one of the fluids has nonvanishing chemical potential, for instance mu(x)< 0 and mu(dm)=0 or mu(x)=0 and mu(dm)> 0, the decay is possible, where mu(x) and mu(dm) are the chemical potentials of dark energy and dark matter, respectively. Using recent cosmological data, we find that, for a fairly simple interaction, the dark matter decay is favored with a probability of similar to 93% over the dark energy decay. This result comes from a likelihood analysis where only background evolution has been considered.