26 research outputs found
Summary of the IADR Cariology Research, Craniofacial Biology, and Mineralized Tissue Groups Symposium, Iguaçu Falls, Brazil, June 2012: Gene-environment Interactions and Epigenetics in Oral Diseases: Enamel Formation and its Clinical Impact on Tooth Defects, Caries, and Erosion.
Characteristics of enamel may influence or modulate individual susceptibility to caries and erosion. These characteristics are defined during development, which is under strict genetic control, but can easily be modified in many ways by environmental factors. In the symposium, translational aspects of embryology, biochemistry, and genetics of amelogenesis were presented. The symposium provided unique insight into how basic sciences integrate with clinically relevant problems. The need for improved understanding of risks at the individual level, taking into consideration both environmental exposures and genetic background, was presented. The symposium was divided into four stepwise and interconnected topics as follows: 1) The Many Faces of Enamel Development; 2) Enamel Pathogenesis: Biochemistry Lessons; 3) Environmental Factors on Enamel Formation; and, 4) Genetic Variation in Enamel Formation Genes
A multi-country test of brief reappraisal interventions on emotions during the COVID-19 pandemic.
The COVID-19 pandemic has increased negative emotions and decreased positive emotions globally. Left unchecked, these emotional changes might have a wide array of adverse impacts. To reduce negative emotions and increase positive emotions, we tested the effectiveness of reappraisal, an emotion-regulation strategy that modifies how one thinks about a situation. Participants from 87 countries and regions (n = 21,644) were randomly assigned to one of two brief reappraisal interventions (reconstrual or repurposing) or one of two control conditions (active or passive). Results revealed that both reappraisal interventions (vesus both control conditions) consistently reduced negative emotions and increased positive emotions across different measures. Reconstrual and repurposing interventions had similar effects. Importantly, planned exploratory analyses indicated that reappraisal interventions did not reduce intentions to practice preventive health behaviours. The findings demonstrate the viability of creating scalable, low-cost interventions for use around the world
Comparação entre a variação da pressão de pulso e o índice de variabilidade pletismográfica como índices dinâmicos de pré-carga em cães anestesiados com isoflurano submetidos à hemorragia hipotensiva por reposição volêmica
Klein, A. V. Comparison of changes in pulse pressure variation and in plethysmographic variability index induced by hypotensive hemorrhage followed by volume replacement in isoflurane-anesthetized dogs. 72 p. Dissertation (MSc) - School of Medicine, São Paulo State University, Botucatu, 2015. The pulse pressure variation (PPV) and the pletysmographic variability index (IVP) are parameters that may identify individuals in which an increase in preload achieved by volume expansion will result in an increase in stroke index (SI) and in cardiac index (CI). This study aimed to compare the PPV and the PVI as dynamic preload indexes in isoflurane-anesthetized dogs undergoing hypotensive hemorrhage followed by volume replacement (VR) with autologous blood. In a prospective study, seven adult dogs weighing 25,1 ± 3,4 kg (mean ± standard deviation) were anesthetized with isoflurane under volume controlled ventilation (tidal volume: 12 mL/kg) and atracurium neuromuscular blockade. End-tidal isoflurane concentrations, adjusted to maintain mean arterial pressure (MAP) at 65 mmHg (± 5 mmHg range) before hemorrhage, were maintained constant throughout the study. Cardiac output was measured by the pulmonary thermodilution technique, while PPV and PVI were derived from invasive blood pressure from a pulse oxymeter placed in the tongue, respectively. Variables were recorded before hemorrhage (baseline), after withdrawing blood until MAP was decreased to 45 mmHg (± 5 mmHg range), and after VR with autologous blood over 30 minutes. Hemorrhage significantly (P < 0.05) decreased SI and CI from baseline; while VR normalized these variables. The PPV and PVI significantly increased from baseline after hemorrhage. Changes from baseline induced by hemorrhage were significantly higher for PPV (11 ± 5%) than for PVI (5 ± 5%). After VR, PPV returned to baseline while PVI decreased significantly from baseline. Changes from hemorrhage induced by VR were ...Klein, A. V. Comparação entre a variação da pressão de pulso e o índice de variabilidade pletismográfica como índices dinâmicos de pré-carga em cães anestesiados com isoflurano submetidos à hemorragia hipotensiva seguida por reposição volêmica. 72 p. Dissertação (Mestrado) - Faculdade de Medicina, Universidade Estadual Paulista, Botucatu, 2015. A variação da pressão de pulso (VPP) e índice de variabilidade pletismográfica (IVP) são parâmetros úteis para identificar os indivíduos onde o aumento da pré-carga obtido pela expansão volêmica resultará em elevação do índice sistólico (IS) e do índice cardíaco (IC). Este estudo objetivou comparar a VPP e o IVP como índices dinâmicos de pré-carga em cães anestesiados com isoflurano submetidos à hemorragia hipotensiva, seguida pela reposição volêmica (RV) com sangue autólogo. Em um estudo prospectivo, sete cães adultos pesando 25,1 ± 3,4 kg (média ± desvio padrão) foram anestesiados com isoflurano e submetidos à ventilação com volume controlado (volume corrente: 12 mL/kg) com o emprego do bloqueador neuromuscular atracúrio. As concentrações expiradas de isoflurano, ajustadas para manter a pressão arterial média (PAM) em 65 mmHg (±5 mmHg de variação) antes da hemorragia, foram mantidas constantes durante o estudo. O débito cardíaco foi obtido através da técnica de termodiluição pulmonar, enquanto a VPP e o IVP foram obtidos através da pressão arterial invasiva e através de um sensor de oxímetro de pulso posicionado na língua, respectivamente. As variáveis estudadas foram coletadas antes da hemorragia (momento basal), após a retirada de sangue até a redução da PAM para 45 mmHg (± 5 mmHg de variação) e após a RV com sangue autólogo durante 30 minutos. A hemorragia diminuiu significativamente (P < 0,05) o IS e o IC em relação ao momento basal, enquanto a RV normalizou estas variáveis. A VPP e o IVP aumentaram..
Evaluation of the isoflurane-sparing effects of a constant rate infusion of remifentanil undergoing mastectomy in dogs
Os objetivos deste estudo são a avaliação dos efeitos de duas taxas fixas de infusão continua de remifentanil na concentração expirada de isoflurano (ETiso) em cadelas submetidas à mastectomia. Foram utilizadas 18 cadelas, 12+2 anos de idade e pesando 15+5 Kg. Os animais foram distribuídos aleatoriamente em 3 grupos (n=6/grupo) e submetidos à mastectomia unilateral devido a neoplasia mamária. Todos os animais foram pré-medicados com morfina (0,5 mg Kg-1) e acepromazina (0,03 mg Kg-1), ambas por via intramuscular (IM). A indução da anestesia foi realizada com propofol (dose-efeito). Os animais foram intubados e conectados a um sistema circular com reinalação de gases. Foi utilizada ventilação com pressão positiva intermitente para manutenção de normocapnia com fluxo de oxigênio de 2 L/min e FiO2 de 100%. A anestesia foi mantida com isoflurano e solução salina (grupo controle [GCON], n=6) ou infusão intravenosa de remifentanil na taxa de 0,15 ?g Kg-1min-1 (REMI 0,15 n=6) ou 0,3 ?g Kg-1min-1 (REMI 0,3 n=6). As variáveis cardiovasculares e a ETiso foram monitoradas antes e a cada 15 minutos após o início da cirurgia. Os dados foram analisados por ANOVA com repetições múltiplas para comparações entre momentos e ANOVA seguida de teste Student Newman Keuls (p£0.05) para comparações entre grupos. A frequência cardíaca foi menor em todos os momentos nos grupos REMI 0,15 e REMI 0,3 em comparação com GCON, sendo que não foram encontradas diferenças estatísticas para essa variável entre os dois grupos com infusão de remifentanil. Adicionalmente, os valores de pressão arterial (PAS, PAM e PAD) não apresentaram diferenças entre grupos. Os valores basais (antes da cirurgia) de ETiso não apresentaram diferenças entre os 3 grupos. Após o início da cirurgia, a ETiso variou entre 1,37±0,3 e 1,05±0,19 no grupo controle; nos grupos REMI 0,15 e REMI 0,3 a ETiso foi 36,5% e 65,7% menor que no grupo controle (M15). A infusão de remifentanil reduz a ETiso de forma dose dependente em animais submetidos a mastectomia radical sem causar alterações cardiopulmonares significativas.The aims of this study were to evaluate the effects of two constant rate infusions of remifentanil on end tidal isoflurane (ETiso) in dogs undergoing mastectomy surgery. Eighteen bitches, 12+2 years of age, weighing 15+5 Kg were randomized into 3 groups (n=6/group) and underwent unilateral mastectomy due to mammary neoplasia. All animals received the premedications of morphine (0.5 mg Kg-1) and acepromazine (0.03 mg Kg-1) by intramuscular route (IM). Propofol dose-effect was used for induction of anesthesia. The animals were intubated and connected to a circle breathing system, and IPPV (intermittent positive pressure ventilation) was used to maintain normocapnia with an oxygen flow rate of 2 L/min and FiO2 100%. Anesthesia was maintained with isoflurane and saline solution (control group [GCON], n=6) or intravenous infusion of remifentanil at a rate of 0.15 ?g Kg-1min-1 (REMI 0.15 n=6) or 0.3 ?g Kg-1min-1 (REMI 0.3 n=6). Cardiopulmonary variables and ETiso were monitored before and every 15 minutes after the start of surgery. The data were analyzed by ANOVA with multiple repetitions between moments and ANOVA followed by the Student Newman Keuls test (p£0.05) for comparisons between groups. Heart rate was lower at all moments in the REMI 0.15 and REMI 0.3 groups than in the GCON, and heart rate was not significantly different between the two remifentanil infusion groups. Additionally, the arterial blood pressure values (SAP, MAP and DAP) were not different between all groups. Baseline values (before surgery) of ETiso were not different between the 3 groups. After the start of surgery, ETiso ranged from 1.37±0.3 to 1.05±0.19 in the control group; in the REMI 0.15 and REMI 0.3 groups, ETiso was 36.5% and 65.7% lower than in the control group (M15). Remifentanil infusion reduced ETiso in a dose-dependent manner in animals undergoing radical mastectomy without causing significant cardiopulmonary alterations
Adrenomedullin induces pulmonary vasodilation but does not attenuate pulmonary hypertension in a sheep model of acute pulmonary embolism
The pulmonary vasodilation induced by adrenomedullin may be beneficial in the acute pulmonary embolism (APE) setting. This study examined effects of adrenomedullin in sheep with microsphere-induced APE. Twenty four anesthetized, mechanically ventilated sheep were randomly assigned into 3 groups (n=8 per group): animals not subjected to any intervention (Sham), animals with APE induced by microspheres (500mg, intravenously) treated 30min later by intravenous physiological saline (Emb group) or intravenous adrenomedullin (50ng/kg/min) during 30min (Emb+Adm group). Plasma concentrations of cyclic adenosine (cAMP) and guanosine monophosphate (cGMP) were determined by enzyme immunoassay. Variables did not change over time in sham animals. In both embolized groups, microsphere injection significantly (P<0.05) increased pulmonary vascular resistance index (PVRI) and mean pulmonary artery pressure (MPAP) from baseline by 181% and 111-142%, respectively (% change in mean values). Adrenomedullin significantly decreased PVRI (18%-25%) and significantly increased cardiac index (22%-25%) from values recorded 30min after APE (E30), without modifying MPAP. Adrenomedullin decreased mean arterial pressure (18%-24%) and systemic vascular resistance index (32%-40%). Embolization significantly increased arterial-to-end tidal CO2 gradient, alveolar-to-arterial O2 gradient, and pulmonary shunt fraction from baseline, but these variables were unaffected by adrenomedullin. While adrenomedullin significantly increased plasma cAMP, cGMP levels were unaltered. Adrenomedullin induces systemic and pulmonary vasodilation, possibly via a cAMP mediated mechanism, without modifying the gas exchange impairment associated with APE. The pulmonary anti-hypertensive effect of adrenomedullin may be offset by increases in cardiac index.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP