Selective versus strategic control against Rhipicephalus microplus in cattle: A comparative analysis of efficacy, animal health, productivity, cost, and resistance management.

This study compared selective control versus strategic control against Rhipicephalus (Boophilus) microplus, under conditions of a real dairy farm. Strategic control requires that all animals be treated with acaricide at regular pre-determined intervals. Selective control only requires treatment of infested animals and only when they are at or above a pre-determined threshold. Tick counts on animals and in pasture were performed and the susceptibility of tick populations to the different treatment methods was evaluated at the beginning and end of the study using the Larval Packet Test, Larval Immersion Test, and Adult Immersion Test. Over the four years of the study strategic control was more advantageous than the selective control as the group experienced lower tick burden on animals and in pasture, absence of skin lesions and myiases, lower operating costs, treatments concentrated in fewer months of the year and lower resistance pressure.

Combinations of amitraz with essential oils from Lippia sidoides and Thymus vulgaris, thymol and thymol acetate for Rhipicephalus microplus control: studies under laboratory and field conditions.

This study aimed to assess the effect of combining amitraz with essential oils (EOs) from Thymus vulgaris and Lippia sidoides, as well as the monoterpenes thymol and thymol acetate, on Rhipicephalus microplus in laboratory conditions, and to select the most effective combination for testing in field conditions. The chemical analysis showed that EOs were mainly composed of monoterpenes, with thymol and p-cymene as the major compounds. In larval (LIT) and adult (AIT) immersion tests using different concentrations of the oils and terpenes mixed with amitraz, the results showed that both EOs and thymol improved the efficacy of amitraz against larvae and engorged females of R. microplus, whereas thymol acetate only enhanced activity against larvae. The most favorable outcome was obtained with the EO of L. sidoides combined with amitraz, resulting in 99 % and 100 % efficacy against larvae and engorged females, respectively. Furthermore, the combination of amitraz with thymol showed presented an efficacy of 94 % and 91 % against larvae and engorged females, respectively. Thus, for the other tests, the combination of thymol + amitraz was chosen due to the ease of working with pure thymol in bioassays, and easier standardization. The immersion test (thymol + amitraz) with semi-engorged females showed 100 % efficacy for the combination of thymol + amitraz, while in tests with different solvents (thymol + amitraz), ethanol being the most effective solvent among those tested (ethanol, Triton, and Tween), resulting in 95 % efficacy on engorged females. In the field test, in treatments with amitraz and thymol + amitraz, efficacy of 54 % and 74 % was observed on day + 3 and 33 % and 43 % on day + 7, respectively. Assessing the reproductive biology of females recovered from animals treated with amitraz or amitraz + thymol, in day + 7, efficacies of 33 % and 52 %, respectively, were observed. EOs from T. vulgaris and L. sidoides and thymol improved the acaricidal activity of amitraz on larvae and engorged females of R. microplus under laboratory conditions, while thymol acetate only enhanced activity against larvae. Thymol increased the efficacy of amitraz under field conditions, however for the development of a commercially available acaricide to R. microplus control, additional studies are needed to increase the efficacy. Further research is needed (by changing concentrations, adding other compounds and/or developing formulations) to increase acaricidal efficacy and develop new effective products to combat R. microplus infestations in cattle.

Do Commercial Insect Repellents Provide Protection against the Tick Amblyomma sculptum (Acari: Ixodidae)?

Amblyomma sculptum is a species of public health interest because it is associated with the transmission of the bacteria that causes Brazilian Spotted Fever (BSF). The use of repellents on humans is a prophylactic measure widely used to provide protection against a series of arthropod vectors, including mosquitoes and ticks. However, in Brazil, the effectiveness of commercial repellents against A. sculptum is little known. Therefore, it is necessary to carry out specific studies to evaluate the repellency of these commercial products, registered for use against mosquitoes, against the star tick. The main goal of the present work was to evaluate the effectiveness of six commercial repellents against A. sculptum. Unfed nymphs, aged between two and eight weeks, were tested against products based on DEET (OFF!® and Repelex®), Icaridin (Exposis® and SBP®), and IR3535 (Johnsons and Henlau). Three bioassays were conducted to evaluate tick behavior: (i) filter paper, (ii) fingertip, and (iii) field. All bases tested showed high repellent activity, differing significantly (p < 0.05) from the control. It was observed the formulation with DEET resulted in the best results in the filter paper bioassay. In the fingertip bioassay, the DEET base repelled a greater number of ticks compared to Icaridin. In the field bioassay, there was no significant difference between the Icaridin base and DEET, and both formulations differed from the control (p < 0.05). The six formulations tested showed significant percentages of repellency against ticks; however, for the fingertip and field bioassays, the products OFF!®, Repelex®, and Exposis® were tested as they showed better performance in the filter paper test. OFF!® showed the best percentage of repellency (100%), followed by Repelex® (96.8%), and Exposis® (93.1%), considering the two-hour period of the bioassay-field-test. Proving the effectiveness of repellents on the market against A. sculptum presented in this study is crucial, since this is the main ectoparasite of humans that can transmit Rickettsia rickettsii when infected. The effectiveness of commercial insect repellents against other tick species that parasitize humans can also be explored.

Cohort profile: Health trajectories of Immigrant Children (CRIAS)-a prospective cohort study in the metropolitan area of Lisbon, Portugal.

PURPOSE: The CRIAS (Health trajectories of Immigrant Children in Amadora) cohort study was created to explore whether children exposed to a migratory process experience different health risks over time, including physical health, cognitive, socioemotional and behavioural challenges and different healthcare utilisation patterns. PARTICIPANTS: The original CRIAS was set up to include 604 children born in 2015, of whom 50% were immigrants, and their parents. Recruitment of 420 children took place between June 2019 and March 2020 at age 4/5 years, with follow-up carried out at age 5/6 years, at age 6/7 years currently under way. FINDINGS TO DATE: Baseline data at age 4/5 years (2019-2020) suggested immigrant children to be more likely to belong to families with less income, compared with non-immigrant children. Being a first-generation immigrant child increased the odds of emotional and behavioural difficulties (adjusted OR 2.2; 95% CI: 1.06 to 4.76); more immigrant children required monitoring of items in the psychomotor development test (38.5% vs 28.3%). The prevalence of primary care utilisation was slightly higher among immigrant children (78.0% vs 73.8%), yet they received less health monitoring assessments for age 4 years. Utilisation of the hospital emergency department was higher among immigrants (53.2% vs 40.6%). Age 5 years follow-up (2020-2021) confirmed more immigrant children requiring monitoring of psychomotor development, compared with non-immigrant children (33.9% vs 21.6%). Economic inequalities exacerbated by post-COVID-19 pandemic confinement with parents of immigrant children 3.2 times more likely to have their household income decreased. FUTURE PLANS: Further follow-up will take place at 8, 10, 12/13 and 15 years of age. Funds awarded by the National Science Foundation will allow 900 more children from four other Lisbon area municipalities to be included in the cohort (cohort-sequential design).

Acaricidal activity of the essential oils from Leptospermum scoparium, Origanum vulgare and Litsea cubeba on Rhipicephalus microplus: Influence of the solvents and search for fractions with higher bioactivity.

The use of natural products in research on tick control for Rhipicephalus microplus is increasing year by year, with promising results. In this regard, the aim of the present study was to phytochemically characterize the essential oils (EOs) of Leptospermum scoparium, Origanum vulgare and Litsea cubeba, and to evaluate the acaricidal activity of these EOs in solutions prepared using ethanol, dimethylsulfoxide (DMSO) and Tween 80 on larvae and females of R. microplus. In addition, three L. scoparium fractions were also isolated and their acaricidal activity on these larvae and adult females was tested. Gas chromatography and mass spectrometry results showed that cis-calamenene (29.82 %), carvacrol (64.85 %) and geranial (42.44 %) were the majority compounds of L. scoparium, O. vulgare and L. cubeba, respectively. Three fractions were isolated from L. scoparium: A1, rich in sesquiterpene hydrocarbons, and A2 and A3, rich in ß-triketones. Bioassays on unfed larvae (immersion test) were performed using all the EOs at concentrations from 2.5 to 10.0 mg/mL; and using the three fractions obtained from L. scoparium EO at concentrations from 0.625 to 10 mg/mL. We observed 100 % mortality of larvae in all treatments with L. scoparium EO at all concentrations (diluted both in DMSO and in ethanol), and in treatments with O. vulgare EO diluted in DMSO. However, L. cubeba EO only gave rise to more than 99 % mortality at a concentration of 10 mg/mL, using the same solvents. For engorged females, the immersion test was performed at concentrations from 2.5 to 10.0 mg/mL. Percentage control greater than 90 % was observed only at the highest concentrations of L. scoparium and O. vulgare EOs diluted in DMSO and ethanol, while L. cubeba EO did not reach 90 % control in any of the treatments. In tests on L. scoparium fractions, larval mortality in the fractions rich in ß-triketones (A2 and A3) was above 97 % at a concentration of 2.5 mg/mL, while in the A1 fraction, rich in sesquiterpene hydrocarbons, at the same concentration (2.5 mg/mL), mortality did not reach 22 %. In the adult immersion test, the percentage control was higher than 98 % at the lowest concentration (2.5 mg/mL) of the A1 fraction, while in the treatments with the fractions A2 and A3, the control levels were 16 and 50 %, respectively. Thus, we can conclude that the EOs of L. scoparium, O. vulgare and L. cubeba have acaricidal activity on R. microplus, as also do the fractions derived from L. scoparium EO.

Percepções de estudantes de Odontologia sobre a contribuição do preceptor / Perceptions of Dentistry students regarding the contribution of preceptors

O objetivo deste estudo foi identificar a percepção de discentes de Odontologia acerca da contribuição dos preceptores no seu processo de formação acadêmica. Este estudo qualitativo abordou 69 estudantes de três Instituições de Ensino Superior públicas e privadas do município do Rio de Janeiro. Os voluntários responderam sobre suas percepções a respeito da contribuição do preceptor no processo formativo. As respostas foram avaliadas pela análise de conteúdo de Bardin e classificadas em 3 categorias temáticas: "A experiência/conhecimento clínico necessário no ensino", "O entendimento do processo de trabalho na Atenção Primária" e "A capacitação profissional". Concluise que, sob a perspectiva do discente, o preceptor é considerado um profissional com perfil necessário para atender às suas demandas acadêmicas, já que possui o conhecimento clínico necessário no ensino e conhece o processo de trabalho no serviço público. A falta de capacitação profissional pode influenciar o processo de aprendizado (AU).

The aim of the present study was to identify the perception of students of the Dentistry regarding the contribution of preceptors in their process of academic training. This qualitative study involved 69 volunteer students from three public and private higher education institutions in the city of Rio de Janeiro. The volunteers described their perceptions regarding the contribution of the preceptor in their training process. The answers were evaluated through Bardin's content analysis and classified into 3 thematic categories: "The clinical knowledge/experience required for teaching"; "The understanding of the process of working in Primary Care" and "Professional training". It was concluded that, from the perspective of the students, the preceptor is considered to have the necessary characteristics to meet their academic demands needs, as they have the necessary clinical knowledge and teaching knowledge and understand the working process in public service. A lack of professional training can influence the learning process (AU).

Prevalência de cárie associada à influência da propaganda nos hábitos alimentares de escolares / Caries prevalence in association with advertisement influence on the food habits of students

O objetivo do estudo foi avaliar a influência das propagandas da TV nos hábitos alimentares de escolares de 12 anos e associação com a prevalência de cárie. Estudo epidemiológico observacional transversal em 294 estudantes utilizou Índice CPO e Questionário estruturado. Os resultados mostraram que quem assistia SBT e TV das 9 às 12 horas tinha 1,73 vezes e 1,66 vezes mais chance de ter cárie. A correlação foi positiva para o tempo de exposição à TV e prevalência de cárie (p=0,02). Concluiu-se que o tempo de exposição à TV pode influenciar hábitos alimentares em crianças e adolescentes, contribuindo para o desenvolvimento da cárie dental

The aim of this study was to assess the influence of TV' propaganda on food habits of students aged 12 years and its association with the prevalence of caries. A cross sectional observational epidemiological study of 294 students used DMFT and structured questionnaire. The outcomes showed that who watched SBT and TV from 9 to 12 o'clock had 1.73 times and 1.66 times more likely to have caries. The correlation was positive to the time for watching TV and prevalence of caries (p=0.02). It was concluded that the time for watching TV can influence the food habits of children and adolescents, contributing to the development of dental caries

Sickle cell disease: a clinical and histopathologic study of the liver in living children.

PURPOSE: To study hepatic lesions in living children with sickle cell disease. Although such lesions are well known, the possibility of chronic persistent damage to the parenchyma resulting from the disease itself or iron overload is controversial. PATIENTS AND METHODS: Sixteen children with sickle cell disease aged 15 months to 18 years were prospectively investigated out of 741 patients younger than 20 years registered at Hemominas Foundation, Brazil. Inclusion criteria for biopsy were as follows: five had positive anti-hepatitis C virus (HCV) antibody, two had positive hepatitis B virus (HBV) surface antigen and persistently increased levels of aminotransferases, and nine underwent biopsy during abdominal surgery. RESULTS: Children with B or C hepatitis were significantly older than the others and also had increased levels of both alanine and aspartate aminotransferases. Lobular architecture was preserved in all nonviral cases; mild to moderate sinusoidal dilatation was present in eight, hepatocellular regenerative activity in six, and focal necrosis and corresponding mild inflammatory infiltrate in three. No fibrosis or bile duct damage was observed. Mild to severe hemosiderosis was present in all children except one. The degree of iron overload was clearly associated with the number of previous blood transfusions. All five children with HCV had chronic hepatitis. One of the children with HBV had incomplete and the other had definite cirrhosis. CONCLUSIONS: These data indicate that chronic hepatic lesions in children with sickle cell disease may be caused by viral damage. Patients without evidence for viral etiology had reversible vascular lesions. Follow-up studies would be necessary to confirm this hypothesis but are precluded for ethical reasons. Hemosiderosis was not associated with fibrosis in any nonviral cases, but a larger number of patients would be necessary to establish valid conclusions.