Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
J Agric Food Chem ; 70(9): 2806-2816, 2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35225607

RESUMO

The synthesis and phytotoxic activity of a series of tyrosol 1,2,3-triazole derivatives are reported herein. Target compounds were synthesized through the copper(I)-catalyzed azide-alkyne cycloaddition reaction (CuAAC), known as click reaction, and these were tested for phytotoxic activity on leaves of wild poinsettia (Euphorbia heterophylla), fleabane (Conyza sumatrensis), and tropical spiderwort (Commelina benghalensis). These are three highly noxious agricultural weeds that challenge available weed control methods, including the use of chemical herbicides. Twenty-five compounds were synthesized and tested. None of the compounds showed phytotoxic activity against C. benghalensis and C. sumatrensis, but almost all of them produced yellowing, bleaching, and necrosis on leaves of E. heterophylla. Two of the tyrosol 1,2,3-triazole derivatives produced more extensive lesions than those produced by the commercial herbicide diquat, used as a positive control (p ≤ 0.05). When applied on leaves of E. heterophylla, these compounds interfered with the stomatal conductance, net photosynthesis, internal carbon concentration, transpiration rate, water-use efficiency, and chlorophyll A and B contents. The interference of such compounds on such photosynthesis-related variables indicates that tyrosol 1,2,3-triazole derivatives may be capable of lowering the competitiveness of E. heterophylla and acting as additional tools for managing this competitive weed in agricultural lands.


Assuntos
Euphorbia , Álcool Feniletílico , Clorofila A , Euphorbia/química , Álcool Feniletílico/análogos & derivados , Triazóis/química , Triazóis/toxicidade
2.
Geroscience ; 43(6): 2693-2705, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34453666

RESUMO

To date, no meta-analytical study evaluating the benefits of resistance exercise intervention on muscular strength and power and functional capacity in acute hospitalized older adults was conducted. Then, to synthesize the emerging evidence on the effects of resistance exercise intervention on muscular strength and power and functional capacity in acute hospitalized older adults, two independent authors performed a systematic search (PubMed, Scopus, Web of Science, and SciELO) until January 2021. Randomized clinical trials were included regarding the effects of resistance exercise and hospital usual care. The Cochrane Collaboration assessment tool was used to analyze the risk of bias. The comparisons included muscular strength (isometric handgrip strength and one-repetition maximum test of leg press), muscular power (output during leg press exercise), and functional capacity (timed-up-and-go, and short physical performance battery). Resistance exercise intervention increased muscular strength (isometric handgrip strength: mean difference = 2.50 kg, 95% confidence interval (CI) = 1.33, 3.67; and one-repetition maximum test of leg press: mean difference = 19.28 kg, 95% confidence interval = 14.70, 23.86) and muscular power (mean difference = 29.52 W, 95% confidence interval = 28.84, 30.21), and functional capacity (timed-up-and-go: mean difference = 3.40 s, 95% confidence interval = 0.47, 6.36; and short physical performance battery: mean difference = 1.29 points, 95% confidence interval = 0.10, 2.48) at discharge compared with hospital usual care. This meta-analysis endorses the increase of muscular strength and power gains and improving the functional capacity in favor of resistance exercise intervention in acute hospitalized older adults. TRIAL REGISTRATION : https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020203658.


Assuntos
Força da Mão , Força Muscular , Idoso , Exercício Físico , Terapia por Exercício , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
3.
J Strength Cond Res ; 35(8): 2089-2094, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31009427

RESUMO

ABSTRACT: Franco, CMC, Carneiro, MAS, de Sousa, JFR, Gomes, GK, and Orsatti, FL. Influence of high- and low-frequency resistance training on lean body mass and muscle strength gains in untrained men. J Strength Cond Res 35(8): 2089-2094, 2021-The aim of this study was to investigate whether high-frequency resistance training (HFRT) performs better in lean body mass (LBM) and muscle strength gains when compared with low-frequency resistance training (LFRT). Eighteen untrained males (height: 1.76 ± 0.05 m, body mass: 78.3 ± 13.5 kg, and age: 22.1 ± 2.2 years) were randomly allocated into HFRT (n = 9) and LFRT (n = 9). Muscle strength {1 repetition maximum (RM) (bench press [BP] and unilateral leg extension [LE])} and LBM (DXA) were assessed at before and after 8 weeks of training. Both groups performed 7 whole-body resistance exercises, standardized to 10 sets per week, 8-12 maximal repetitions, and 90-120 seconds of rest in a 5-day resistance training routine. The LFRT performed a split-body routine, training each specific muscle group once a week. The HFRT performed a total-body routine, training all muscle groups every session and progressed from a training frequency of once per week to a training frequency of 5 times per week. Lean body mass increased without differences between groups (HFRT = 1.0 kg vs. LFRT = 1.5 kg; p = 0.377). Similarly, 1RM increased without differences between groups (right LE, HFRT = 21.2 kg vs. LFRT = 19.7 kg, p = 0.782; BP, HFRT = 7.1 kg vs. LFRT = 4.5 kg, p = 0.293). These findings suggest that in young untrained men, progressing from a training frequency of once per week to a training frequency of 5 times per week with equated volume produces similar gains in LBM and muscle strength as a constant training frequency of once per week, over an 8-week training period.


Assuntos
Treinamento Resistido , Adulto , Composição Corporal , Exercício Físico , Humanos , Masculino , Força Muscular , Músculo Esquelético , Adulto Jovem
4.
J Med Entomol ; 57(1): 181-186, 2020 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-31332448

RESUMO

Musca domestica L., 1758, is an important mechanical vector of several pathogens for humans and livestock, making it essential to study new alternatives of more efficient and safer control for this dipteran. This study evaluated the toxicity of the phenylpropanoids eugenol and (E)-cinnamaldehyde on its life stages. A contact test with 10 repetitions (n = 10) was performed for each substance concentration on each post-embryonic immature life stage. Both substances presented insecticidal activity on the immature life stages of the dipteran, and secondary effects on development caused by sublethal concentrations. Larvicidal activity was shown from the 1.25 mg/ml concentration by eugenol and from 2.5 mg/ml by (E)-cinnamaldehyde, and both substances had a 100% larval treatment efficacy (LTE) from the 5mg/ml concentration. For pupal treatment, (E)-cinnamaldehyde differed from the control from the 10 mg/ml concentration (P < 0.05), and both phenylpropanoids caused malformation in adults from 10 mg/ml. The highest pupal treatment efficacy (PTE) was obtained from the 30 mg/ml concentration, 67.2% for (E)-cinnamaldehyde, and 32% for eugenol. The products tested in this study showed high larvicidal potential, and both presented pupicidal effects and caused malformation in adults from treated pupae.


Assuntos
Acroleína/análogos & derivados , Eugenol , Moscas Domésticas , Controle de Insetos , Inseticidas , Animais , Moscas Domésticas/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Pupa/crescimento & desenvolvimento
5.
J Strength Cond Res ; 33 Suppl 1: S152-S158, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30640303

RESUMO

Franco, CMdC, Carneiro, MAdS, Alves, LTH, Júnior, GNdO, de Sousa, JdFR, and Orsatti, FL. Lower-load is more effective than higher-load resistance training in increasing muscle mass in young women. J Strength Cond Res 33(7S): S152-S158, 2019-This study was designed to investigate the impact of load (higher vs. lower) performed until or close to volitional fatigue on muscle strength (MS) and fat and bone-free lean mass (FBFM) in young women. To do this, 32 women performed resistance training (RT) in 1 of 2 conditions: lower-load RT (LL; n = 14, age = 24.3 ± 4.8 years and body mass index [BMI] = 23.3 ± 2.8 kg·m) and higher-load RT (HL; n = 18, age = 23.0 ± 3.3 years and BMI = 22.4 ± 3.3 kg·m). Leg FBFM (DXA) and MS (1 repetition maximum-unilateral leg extension [LE]) were evaluated before and after 9 weeks (the first week was used for familiarization) of RT. Both groups performed 3 unilateral exercises (LE, leg curl, and leg press), 3 sets per exercise, 60-90 seconds of rest between sets, 2 days per week. In the LL group, the loads used in the exercises were the loads necessary to perform 30-35 repetitions in the first set. For the HL group, the loads used were the loads necessary to perform 8-10 repetitions in the first set. The LL group showed higher RT volume than the HL. Both groups showed leg muscle mass gains (p < 0.05). However, the LL group was better [p = 0.032 and effect size (eta = 0.14 [large]) than the HL group in leg FBFM gains (LL = 0.3 kg [IC 95%: 0.4 kg; 0.2 kg] and HL = 0.1 kg [IC 95%: 0.2 kg; 0.0 kg]). Both groups showed MS gains, without any difference between them (LL = 3.4 kg [IC 95%: 4.4 kg; 2.5 kg] and HL = 4.2 kg [IC 95%: 5.1 kg; 3.3 kg]; p = 0.239). Thus, lower-load RT is more effective than higher-load RT in increasing FBFM, but not MS in novice young women.


Assuntos
Composição Corporal , Força Muscular , Músculo Esquelético/fisiologia , Treinamento Resistido/métodos , Adulto , Feminino , Humanos , Distribuição Aleatória , Descanso/fisiologia , Adulto Jovem
6.
J Strength Cond Res ; 33 Suppl 1: S130-S139, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29489727

RESUMO

Gomes, GK, Franco, CM, Nunes, PRP, and Orsatti, FL. High-frequency resistance training is not more effective than low-frequency resistance training in increasing muscle mass and strength in well-trained men. J Strength Cond Res 33(7S): S130-S139, 2019-We studied the effects of 2 different weekly frequency resistance training (RT) protocols over 8 weeks on muscle strength and muscle hypertrophy in well-trained men. Twenty-three subjects (age: 26.2 ± 4.2 years; RT experience: 6.9 ± 3.1 years) were randomly allocated into the 2 groups: low-frequency resistance training (LFRT, n = 12) or high-frequency resistance training (HFRT, n = 11). The LFRT performed a split-body routine, training each specific muscle group once a week. The HFRT performed a total-body routine, training all muscle groups every session. Both groups performed the same number of sets (10-15 sets) and exercises (1-2 exercise) per week, 8-12 repetitions maximum (70-80% of 1 repetition maximum [1RM]), 5 times per week. Muscle strength (bench press and squat 1RM) and lean tissue mass (dual-energy x-ray absorptiometry) were assessed before and at the end of the study. Results showed that both groups improved (p < 0.001) muscle strength {LFRT and HFRT: bench press = 5.6 kg (95% confidence interval [CI]: 1.9-9.4) and 9.7 kg (95% CI: 4.6-14.9) and squat = 8.0 kg (95% CI: 2.7-13.2) and 12.0 kg (95% CI: 5.1-18.1), respectively} and lean tissue mass (p = 0.007) (LFRT and HFRT: total body lean mass = 0.5 kg [95% CI: 0.0-1.1] and 0.8 kg [95% CI: 0.0-1.6], respectively) with no difference between groups (bench press, p = 0.168; squat, p = 0.312, and total body lean mass, p = 0.619). Thus, HFRT and LFRT are similar overload strategies for promoting muscular adaptation in well-trained subjects when the sets and intensity are equated per week.


Assuntos
Adaptação Fisiológica , Composição Corporal , Força Muscular , Músculo Esquelético/fisiologia , Treinamento Resistido/métodos , Absorciometria de Fóton , Adulto , Humanos , Masculino , Distribuição Aleatória , Adulto Jovem
7.
Vet Parasitol ; 260: 1-4, 2018 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-30197007

RESUMO

This study reports the comparative evaluation of the activity of carvacrol, thymol, eugenol and their respective acetylated derivatives (carvacrol acetate, thymol acetate and eugenol acetate) on Rhipicephalus microplus, to verify the possible influence of the acetate group. The acetylated derivatives were prepared from reactions of the phenolic compounds with acetic anhydride/pyridine. The formation of the products was confirmed by analysis of hydrogen and carbon-13 nuclear magnetic resonance (1H and 13C NMR) spectra. The larval packet test was used to evaluate the acaricidal activity, with concentrations of 0.312, 0.625, 1.25, 2.5, 5.0, 7.5, 10.0 and 15.0 mg/mL. Thymol and carvacrol resulted in 100% mortality starting at the concentration of 2.5 mg/mL, while the same was observed for carvacrol acetate starting at the concentration of 5.0 mg/mL. For the other treatments, 100% mortality was only achieved in the groups treated with the highest concentration (15.0 mg/mL). The LC50 and LC90 values (mg/mL) of carvacrol acetate (2.49, 4.21), thymol acetate (2.97, 8.52) and eugenol acetate (4.25, 13.10) were higher than those for the corresponding precursor molecules carvacrol (0.83, 2.02), thymol (1.26, 2.21) and eugenol (2.77, 5.35). The acetylation process did not enhance the activity of these substances on unengorged larvae of R. microplus, since the precursor substances (carvacrol, thymol and eugenol) had greater efficacy.


Assuntos
Acaricidas/farmacologia , Anti-Infecciosos/farmacologia , Eugenol/farmacologia , Monoterpenos/farmacologia , Rhipicephalus/efeitos dos fármacos , Timol/farmacologia , Acaricidas/química , Acetilação , Animais , Bovinos/parasitologia , Cimenos , Eugenol/química , Técnicas In Vitro , Larva/efeitos dos fármacos , Monoterpenos/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Timol/química
8.
Vet Parasitol ; 254: 147-150, 2018 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-29657000

RESUMO

This study evaluated the acaricidal activity of the methanol extract of Acmella oleracea with 0.187% of spilanthol against immature stages of Amblyomma sculptum. The packet test was used to evaluate the extract's activity on unengorged larvae and nymphs, testing concentrations of 0.4 to 50 mg/mL for larvae and 12.5 to 200.0 mg/mL for nymphs. For the engorged stages, the immersion test was used, at concentrations of 0.4 to 50 mg/mL for larvae and 12.5 to 200.0 mg/mL for nymphs. The methanol extract caused 100% mortality of the unengorged larvae and nymphs starting at concentrations of 12.5 and 200.0 mg/mL, respectively. For engorged larvae and nymphs, the mortality was 100% starting from concentrations of 12.5 and 150.0 mg/mL, respectively. The LC50 for unengorged larvae was 3.2 mg/mL, while for engorged larvae it was 6.6 mg/mL. For unengorged nymphs, the LC50 was 38.5 mg/mL, but it was not possible to calculate the corresponding value for engorged nymphs because the data did not fit the probit model. These results demonstrate that the methanol extract of A. oleracea has acaricidal activity against different immature stages of A. sculptum.


Assuntos
Acaricidas , Asteraceae/química , Ixodidae , Extratos Vegetais , Alcamidas Poli-Insaturadas , Animais , Ixodidae/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Ninfa/crescimento & desenvolvimento
9.
Pest Manag Sci ; 74(7): 1637-1645, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29318774

RESUMO

BACKGROUND: In the context of the demand for more efficient herbicides, the aim of the present work was to synthesize anilides via simple methods, and evaluate their herbicidal activities through seed germination assays. In silico studies were carried out to identify the enzyme target sites in plants for the most active anilides. RESULTS: A total of 18 anilides were prepared via one-pot reaction in yields that varied from 36 to 98% through reactions of anilines with sorbic chloride and hexanoic anhydride. According to seed germination assays in three dicotyledonous and one monocotyledonous plant species, the most active anilides showed root and shoot growth inhibition superior to that of Dual (S-metolachlor). In silico studies indicated that histone deacetylase was the probable enzyme target site in plants for these substances. The affinities of the most active anilides for the binding sites of this enzyme were equal to or higher than those calculated for its inhibitors. CONCLUSION: Anilides 4d, 4e, 4 g, and 4 h are promising candidates for the development of novel herbicides. According to in silico studies, they inhibit histone deacetylase in plants, which can be exploited for the development of new weed control methods. © 2018 Society of Chemical Industry.


Assuntos
Anilidas/toxicidade , Bidens/efeitos dos fármacos , Cucumis sativus/efeitos dos fármacos , Herbicidas/toxicidade , Lactuca/efeitos dos fármacos , Simulação de Acoplamento Molecular , Cebolas/efeitos dos fármacos , Anilidas/síntese química , Herbicidas/síntese química , Controle de Plantas Daninhas
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA