Essential oil from leaves of Eugenia calycina Cambes: Natural larvicidal against Aedes aegypti

BACKGROUND

Eugenia calycina is an endemic species in the Brazilian savannah (the Cerrado) and it is threatened with extinction. Several species of Eugenia are used as insecticides or insect repellents. No data are available on the larvicidal activity of E. calycina. The chemical composition of the essential oil (EO) from leaves of Eugenia calycina was analyzed by gas chromatography coupled to mass spectrometry (GC-MS) and the larvicidal activity against Aedes aegypti larvae in the third stage of development was studied.

RESULTS

Oxygenated and non-oxygenated sesquiterpenes were identified, and the main compounds were bicyclogermacrene, spathulenol, and β-caryophyllene. The EO was fractionated in a chromatographic column and three compounds were isolated and identified: spathulenol, aromadendrane-4β,10α-diol, and 1β-11-dihydroxy-5-eudesmene. It is the first time that the last two compounds have been identified in E. calycina. The exposure times in the larvicidal test were 24 h and 48 h and the LC₅₀ values obtained were 199.3 and 166.4 μg mL^-1 . The cytotoxicity of the EO in mammalian cells (HeLa and Vero) was evaluated for 24 and 48 h of incubation. The cytotoxic concentrations of the EO for HeLa and Vero cells (266.8 ± 46.5 and 312.1 ± 42.5 μg mL^-1 , respectively) in 48 h of exposure were higher than the LC₅₀ , showing low cytotoxicity at the concentration exhibiting larvicidal activity, resulting in a positive selectivity index.

CONCLUSION

These results indicate that the EO of E. calycina showed high activity against the A. aegypti larvae but lower cytotoxicity to mammalian cells. The leaves of E. calycina are therefore a very promising source of natural larvicidal products. © 2020 Society of Chemical Industry.

Dose to the interventional radiologist in CTF-guided procedures

The aim of this work was to assess the occupational dose received by an interventional radiologist (IR) during computed tomography fluoroscopy (CTF)-guided procedures; to identify the most exposed areas of the body including the hands and fingers; to suggest recommendations for individual monitoring; and to improve radiation safety of the practice. A total of 53 CTF-guided procedures were studied. Twelve whole-body dosimeters were worn by the IR in each procedure for the assessment of the personal dose equivalent, H_p(10), on the chest, waist, and back, both over and under the lead apron, as well as the personal dose equivalent, H_p(0.07), on both arms, knees, and feet. Special gloves with casings to fit extremity dosimeters were prepared to assess H_p(0.07) to the fingers. The measured chest dose values were higher than those on the waist and back; the dominant hand or the left side was the most exposed. In general, the ring, middle, and index fingers of the dominant hand were the most exposed (maximum in the 36-39 mSv range), while wrist dose was negligible compared to finger doses. Based on the results obtained the following recommendations are suggested: protective devices (lead aprons, thyroid shield, and goggles) should be worn; H_p(10) should be assessed at the chest level both above and below the lead apron; finger doses can be measured on the basis of each middle finger; the arm closer to the beam should be monitored; and finally, a wrist dosimeter will not provide useful information.

Ventilation distribution as a contributor to the functional exercise capacity in patients with systemic sclerosis-associated interstitial lung disease without pulmonary hypertension

Phenotypic differences have been described between patients with systemic sclerosis (SSc)-associated interstitial lung disease (ILD) and SSc-associated pulmonary hypertension, including performance differences in the 6-min walk test (6MWT). Moreover, the correlations between the 6MWT and traditional pulmonary function tests (PFTs) are weak, indicating the need to search for new parameters that explain exercise performance. Thus, our objective was to evaluate the impact of ventilation distribution heterogeneity assessed by the nitrogen single-breath washout (N2SBW) test and peripheral muscle dysfunction on the exercise capacity in patients with SSc-ILD and limited involvement of the pulmonary parenchyma. In this cross-sectional study, 20 women with SSc-ILD and 20 matched controls underwent PFTs (including spirometry, diffusing capacity for carbon monoxide (DLco), and the N2SBW test) and performed the 6MWT and knee isometric dynamometry. The 6-min walking distance (6MWD, % predicted) was strongly correlated with the phase III slope of the single-breath nitrogen washout (phase III slopeN2SBW) (r=-0.753, P<0.0001) and reasonably correlated with the forced vital capacity (FVC) (r=0.466, P=0.008) and DLco (r=0.398, P=0.011). The peripheral oxygen saturation (SpO2) during exercise was not significantly correlated with any of the pulmonary or muscle function parameters. The phase III slopeN2SBW was the only predictive variable for the 6MWD, whereas quadriceps strength and FVC/DLco were predictive variables for SpO2. Ventilation distribution heterogeneity is one factor that contributes to a lower 6MWD in SSc-ILD patients. In addition, muscle dysfunction and abnormal lung diffusion at least partly explain the decreased SpO2 of these patients.

Preliminary assessment of the dose to the interventional radiologist in fluoro-CT-guided procedures

A preliminary assessment of the occupational dose to the intervention radiologist received in fluoroscopy computerised tomography (CT) used to guide the collection of lung and bone biopsies is presented. The main aim of this work was to evaluate the capability of the reading system as well as of the available whole-body (WB) and extremity dosemeters used in routine monthly monitoring periods to measure per procedure dose values. The intervention radiologist was allocated 10 WB detectors (LiF: Mg, Ti, TLD-100) placed at chest and abdomen levels above and below the lead apron, and at both right and left arms, knees and feet. A special glove was developed with casings for the insertion of 11 extremity detectors (LiF:Mg, Cu, P, TLD-100H) for the identification of the most highly exposed fingers. The H(p)(10) dose values received above the lead apron (ranged 0.20-0.02 mSv) depend mainly on the duration of the examination and on the placement of physician relative to the beam, while values below the apron are relatively low. The left arm seems to receive a higher dose value. H(p)(0.07) values to the hand (ranged 36.30-0.06 mSv) show that the index, middle and ring fingers are the most highly exposed. In this study, the wrist dose was negligible compared with the finger dose. These results are preliminary and further studies are needed to better characterise the dose assessment in CT fluoroscopy.

Impact of Forpus xanthopterygius (Spix, 1824) (Aves, Psittacidae) on flowers of Handroanthus serratifolius (Vahl.) S. O. Grose (Bignoniaceae)

Handroanthus serratifolius produces flowers during the dry season in the Cerrado biome, and it may be an important food source to some bird species. For Psittacidae species, like Forpus xanthopterygius, flowers are important in their diet. This study intended to characterize the behavior of F.xanthopterygius and evaluate the damage to the flowering and in the reproduction of H. serratifolius. Four individuals of H. serratifolius were observed for 60 hours to register size of groups, the time and duration of visit, and the number of flowers predated by F.xanthopterygius. The groups that visited the plants had between 2 and 12 individuals. The mean time of visits was 60.31 minutes (+/-22.29). The size of groups was correlated to number of flowers predated and was influenced by number of flowers offered. During the flowering, each H. serratifolius individual loses approximately 1,052 flowers per week.

Photon track evolution

Given the time scale of biological, biochemical, biophysical and physical effects in a radiation exposure of living tissue, the first physical stage can be considered to be independent of time. All the physical interactions caused by the incident photons happen at the same starting time. From this point of view it would seem that the evolution of photon tracks is not a relevant topic for analysis; however, if the photon track is considered as a sequence of several interactions, there are several steps until the total degradation of the energy of the primary photon. We can characterise the photon track structure by the probability p(E,j), that is, the probability that a photon with energy E suffers j secondary interactions. The aim of this work is to analyse the photon track structure by considering j as a step of the photon track evolution towards the total degradation of the photon energy. Low energy photons (<150 keV) are considered, with water phantoms and half-extended geometry. The photon track evolution concept is presented and compared with the energy deposition along the track and also with the spatial distribution of the several steps in the photon track.

Comparison of deterministic and Monte Carlo methods in shielding design

In shielding calculation, deterministic methods have some advantages and also some disadvantages relative to other kind of codes, such as Monte Carlo. The main advantage is the short computer time needed to find solutions while the disadvantages are related to the often-used build-up factor that is extrapolated from high to low energies or with unknown geometrical conditions, which can lead to significant errors in shielding results. The aim of this work is to investigate how good are some deterministic methods to calculating low-energy shielding, using attenuation coefficients and build-up factor corrections. Commercial software MicroShield 5.05 has been used as the deterministic code while MCNP has been used as the Monte Carlo code. Point and cylindrical sources with slab shield have been defined allowing comparison between the capability of both Monte Carlo and deterministic methods in a day-by-day shielding calculation using sensitivity analysis of significant parameters, such as energy and geometrical conditions.

[Sport as integration factor of the physically handicapped in our society]

The objective of this study was to make use of sports as a rehabilitation method, as well as to assess the physical, psychological, and social aspects of those present some physical handicap, particularly those who have some kind of chronic disease and are no longer taking part in any rehabilitation program. Thirty handicapped people were evaluated: fifteen started with basketball and fifteen with swimming, according either to the specific preference of each one of them or to the degree and kind of physical impairment. They were submmited to the following evaluations: clinical examination, physiotherapy assessment, social interview and use of the Rivermead Social Scale, functional classification of the sport, use of the Barthel and Rivermead Functional Scales, and the psychological profile test (POMS). After two years, no relevant change in the moving evolution of the athletes were reported. Concerning the POMS psychological test, both basketball and swimming groups presented with high vigor and low depression levels. Considering the social aspects, both groups presented substantial improvement, specially regarding their relationship to one person or more people and also in the everyday activities (be it social, leisure, or domestic), thus leading them to better social integration. This essay shows that sport can bring people who are physically impaired a better social integration and physical conditions.

[Blood pressure in school children and adolescents - The Belo Horizonte study]

OBJECTIVE: To investigate epidemiological aspects of blood pressure (BP) levels, and the prevalence of arterial hypertension in a representative sample of the whole elementary and high school population of the city of Belo Horizonte (state of Minas Gerais, southeastern Brazil). To describe the blood pressure levels found and the prevalence of BP levels above the 90th and 95th percentiles in the first and second measurements. To evaluate prevalence using four different normality references separately to assess the impact of choice of reference. To study the frequency at which the studentś blood pressure has been evaluated.METHODS: In an observational cross-sectional epidemiological study, we studied a sample of 1005 students, aged 6 to 18 year, randomized from an universe of 486,166 students from the 521 public and private elementary and high schools in the city. Each student was evaluated by means of a personal interview, anthropometric measurements, and two blood pressure measurements in a single visit and at a 10-minute interval.RESULTS: The systolic and diastolic blood pressure levels, by age and gender, were slightly lower than those described by the Task Force Report (1987) and by Rosner et al. (1993). The prevalence of BP levels (systolic or diastolic) over the 95th percentile were, according to the reference used: 8.7% - Task Force Report (1987); 5.5% - Rosner et al. (1993); 6.5% - Update on the Task Force Report (1996); and 9.8% - the 95th percentile from our own study. In the second measurement these prevalence rates dropped to 4.9%; 2.4%; 3.5% and 5.8%, respectively.CONCLUSIONS: We present a detailed description (mean values and standard deviations, and the 90th, 95th and 99th percentiles by age and gender) of the BP levels found in both measurements. Mean values and upper percentiles found in this study are very close to those found in the American references, which validates the current use of these references in Brazil. The prevalence of 9.0% of BP levels above the 90th percentile in two measurements made at random hints at the number of children who should be monitored for hypertension, and reinforces the importance of routine evaluation of blood pressure at every pediatric examination.