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1.
Environ Res ; : 119215, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38782333

RESUMO

Since risk assessments of tropospheric ozone (O3) are crucial for agricultural and forestry sectors, there is a growing body for realistic assessments by a stomatal flux-based approach in Free-Air Controlled Exposure (FACE) facilities. Ozone risks are normally described as relative risks (RRs), which are calculated by assuming the biomass or yield at zero O3 dose as "reference". However, the estimation of the reference biomass or yield is challenging due to a lack of O3-clean-air treatment at the FACEs and the extrapolation without data in a low O3 range increases the bias for estimating the reference values. Here, we reviewed a current methodology for the risk assessment at FACEs and presented a simple and effective way ("modified Paoletti's approach") of defining RRs just using biomass or yield data with a range of expected impacts under the FACE conditions hypothesizing three possible scenarios based on prediction limits using 95% credible intervals (CI) (1. Best fit using the intercept as reference, 2. Optimistic scenario using a lower CI and 3. Worst scenario using an upper CI). As a result, O3-sensitive species show a relatively narrow effect range (optimistic vs. worst scenario) whereas a wide range of response may be possibly taken in resistant species. Showing a possible effect range allows for a comprehensive understanding of the potential risks and its uncertainties related to a species sensitivity to O3. As a supporting approach, we also recommend to use scientifically relevant tools (i.e., ethylenediurea treatments; mechanistic plant models) for strengthening the obtained results for the RRs against O3. Interestingly, the moderately sensitive or resistant species showed non-linear rather than linear dose-response relationships, suggesting a need for the flexible functional form for the risk assessment to properly describe the complex plant response such as hormesis, which depends on their plasticity to O3 stress.

2.
Braz J Med Biol Res ; 53(10): e9815, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32813851

RESUMO

Body fat distribution predicts cardiovascular events better than body-mass index (BMI). Waist circumference (WC) and neck circumference (NC) are inexpensive anthropometric measurements. We aimed to present the conditional distribution of WC and NC values according to BMI, stratified by age and sex, from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) baseline data. We analyzed 15,085 ELSA-Brasil participants with complete data. We used spline quantile regression models, stratified by sex and age, to estimate the NC and WC quantiles according to BMI. To test a putative association between age and median NC or WC values, we built sex-specific median regression models using both BMI and age as explanatory variables. We present estimated 25th, 50th, 75th, and 90th percentiles for NC and WC values, according to BMI, age, and sex. Predicted interquartile intervals for NC values varied from 1.6 to 3.8 cm and, for WC values, from 5.1 to 10.3 cm. Median NC was not associated with age in men (P=0.11) nor in women (P=0.79). However, median WC increased with advancing age in both sexes (P<0.001 for both). There was significant dispersion in WC and NC values for a given BMI and age strata for both men and women. WC, but not NC values, were associated with increasing age. The smaller influence of advancing age on the relationship between BMI and NC (compared to WC) values may be useful in longitudinal studies.


Assuntos
Pescoço , Adulto , Idoso , Índice de Massa Corporal , Brasil , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Fatores de Risco , Circunferência da Cintura
3.
Braz. j. med. biol. res ; 53(10): e9815, 2020. tab, graf
Artigo em Inglês | LILACS, Coleciona SUS | ID: biblio-1132475

RESUMO

Body fat distribution predicts cardiovascular events better than body-mass index (BMI). Waist circumference (WC) and neck circumference (NC) are inexpensive anthropometric measurements. We aimed to present the conditional distribution of WC and NC values according to BMI, stratified by age and sex, from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) baseline data. We analyzed 15,085 ELSA-Brasil participants with complete data. We used spline quantile regression models, stratified by sex and age, to estimate the NC and WC quantiles according to BMI. To test a putative association between age and median NC or WC values, we built sex-specific median regression models using both BMI and age as explanatory variables. We present estimated 25th, 50th, 75th, and 90th percentiles for NC and WC values, according to BMI, age, and sex. Predicted interquartile intervals for NC values varied from 1.6 to 3.8 cm and, for WC values, from 5.1 to 10.3 cm. Median NC was not associated with age in men (P=0.11) nor in women (P=0.79). However, median WC increased with advancing age in both sexes (P<0.001 for both). There was significant dispersion in WC and NC values for a given BMI and age strata for both men and women. WC, but not NC values, were associated with increasing age. The smaller influence of advancing age on the relationship between BMI and NC (compared to WC) values may be useful in longitudinal studies.


Assuntos
Pescoço , Brasil , Índice de Massa Corporal , Fatores de Risco , Estudos Longitudinais , Circunferência da Cintura
4.
Naunyn Schmiedebergs Arch Pharmacol ; 380(4): 337-44, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19557396

RESUMO

The present study examined the antinociceptive effects of (O-methyl) N-benzoyl-tyramine (riparin I, ripI) isolated from the unripe fruit of Aniba riparia in chemical and thermal behavioral models of pain, such as acetic acid-induced abdominal writhing, formalin, and hot-plate tests in mice. Moreover, the involvement of the nitric oxide pathway as well as the opioid system in the antinociceptive action of ripI in the formalin test was investigated. RipI was administered both orally and intraperitoneally to male mice at single doses of 25 and 50 mg/kg. In the acetic acid-induced abdominal writhing, ripI decreased the number of writhings at both doses. In addition, in the formalin test, ripI reduced the paw licking time at both phases of the test. The effect of the highest dose of ripI in mice formalin test on the early phase was not reversed by naloxone (opioid receptor antagonist) but it was reversed by l-arginine (a nitric oxide precursor) in the late phase, suggesting that ripI may not act through opioid system and possibly acts through inhibition of nitric oxide pathway. In the hot-plate test, ripI increased the reaction time in the hot-plate test at the dose of 25 mg/kg, i.p., confirming the result found in the formalin test. Based on the obtained results, it is suggested that ripI presents antinociceptive activity that may be due to peripheral mechanisms (nitric oxide pathway) and central mechanisms, discarding the involvement of opioid system.


Assuntos
Analgésicos/farmacologia , Benzamidas/farmacologia , Lauraceae , Dor/prevenção & controle , Tiramina/análogos & derivados , Ácido Acético , Administração Oral , Analgésicos/administração & dosagem , Analgésicos Opioides/farmacologia , Animais , Arginina/farmacologia , Comportamento Animal/efeitos dos fármacos , Benzamidas/administração & dosagem , Benzamidas/isolamento & purificação , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Formaldeído , Temperatura Alta , Injeções Intraperitoneais , Lauraceae/química , Masculino , Camundongos , Morfina/farmacologia , NG-Nitroarginina Metil Éster/farmacologia , Naloxona/farmacologia , Antagonistas de Entorpecentes/farmacologia , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Dor/etiologia , Dor/metabolismo , Dor/psicologia , Medição da Dor , Tempo de Reação/efeitos dos fármacos , Fatores de Tempo , Tiramina/administração & dosagem , Tiramina/isolamento & purificação , Tiramina/farmacologia
5.
Life Sci ; 84(3-4): 105-10, 2009 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-19056404

RESUMO

This study assesses the antinociceptive effect induced by different dosages of topiramate (TP), an anticonvulsant drug that is orally administered in models of neuropathic pain and acute pain in rats and mice, respectively. Orally administered TP (80 mg/Kg) in mice causes antinociception in the first and second phases of a formalin test, while in doses of 20 and 40 mg/Kg it was only effective in the second phase. TP (80 mg/Kg, p.o) also exhibited antinociceptive action in the hot plate test, however, it did not have an effect in the capsaicin test in mice, nor in the model of neuropathic pain in diabetic rats. The antinociceptive effect caused by TP (80 mg/Kg, p.o) in the formalin test was reversed by prior treatment with naloxone (opioid antagonist), but not with glibenclamide (antagonist of the potassium channel), ondansetron (antagonist of the serotonin 5HT3 receptor) or cyproheptadine (antagonist of the serotonin 5HT2A receptor).The data show that TP has an important antinociceptive effect in the models of nociception induced by chemical (formalin) or thermal (hot plate) stimuli, and that the opioid system plays a part in the antinociceptive effect, as shown by formalin.


Assuntos
Analgésicos/uso terapêutico , Neuropatias Diabéticas/tratamento farmacológico , Frutose/análogos & derivados , Dor/tratamento farmacológico , Doença Aguda , Animais , Modelos Animais de Doenças , Frutose/uso terapêutico , Masculino , Camundongos , Medição da Dor , Receptor 5-HT2A de Serotonina/fisiologia , Receptores 5-HT3 de Serotonina/fisiologia , Topiramato
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