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Tropical Medicine & International... Jul 2011This review aims to examine the effectiveness of citronella preparation used as a mosquito repellent. (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
This review aims to examine the effectiveness of citronella preparation used as a mosquito repellent.
METHODS
Multiple computerized databases such as MEDLINE, EMBASE, Cochrane CENTRAL, CINAHL, and AMED, were searched for controlled laboratory experiments that compared the effectiveness of citronella products to control in repelling Aedes, Anopheles and Culex mosquitoes using the cage or room methods. Outcomes measures were protection time and percentage repellency. The weighted mean difference and 95% confidence interval were calculated comparing the outcomes in the citronella and control groups. Meta-analysis was performed using the DerSimonian and Laird method under a random-effects model.
RESULTS
Eleven studies met inclusion criteria. Based on a meta-analysis of studies using the cage method, protection time of the citronella oil for preventing Aedes mosquitoes was less than that in the DEET (N,N-diethyl-m-toluamide) group, with a difference in protection time of 253 min (95% confidence interval: 169-336). The combination of citronella oil and vanillin is likely to have a longer protection time compared with citronella oil alone. In studies using the room method, citronella oil and/or the combination of citronella oil and vanillin provided complete repellency at least 3 h. In Anopheles and Culex mosquitoes, a combination of citronella oil and vanillin product demonstrated a comparable protection time against DEET; however, it remained inconclusive due to a limited number of studies.
CONCLUSIONS
Citronella products are less effective than DEET products in terms of duration of protection. Adding vanillin to citronella oil products could prolong the protection time.
Topics: Aedes; Animals; Anopheles; Benzaldehydes; Culex; Culicidae; DEET; Humans; Insect Bites and Stings; Insect Repellents; Plant Oils; Time Factors
PubMed: 21481108
DOI: 10.1111/j.1365-3156.2011.02781.x -
European Journal of Preventive... Mar 2017Aims Darapladib, a potent inhibitor of lipoprotein-associated phospholipase A (Lp-PLA), has not reduced risk of cardiovascular disease outcomes in recent randomized... (Review)
Review
Aims Darapladib, a potent inhibitor of lipoprotein-associated phospholipase A (Lp-PLA), has not reduced risk of cardiovascular disease outcomes in recent randomized trials. We aimed to test whether Lp-PLA enzyme activity is causally relevant to coronary heart disease. Methods In 72,657 patients with coronary heart disease and 110,218 controls in 23 epidemiological studies, we genotyped five functional variants: four rare loss-of-function mutations (c.109+2T > C (rs142974898), Arg82His (rs144983904), Val279Phe (rs76863441), Gln287Ter (rs140020965)) and one common modest-impact variant (Val379Ala (rs1051931)) in PLA2G7, the gene encoding Lp-PLA. We supplemented de-novo genotyping with information on a further 45,823 coronary heart disease patients and 88,680 controls in publicly available databases and other previous studies. We conducted a systematic review of randomized trials to compare effects of darapladib treatment on soluble Lp-PLA activity, conventional cardiovascular risk factors, and coronary heart disease risk with corresponding effects of Lp-PLA-lowering alleles. Results Lp-PLA activity was decreased by 64% ( p = 2.4 × 10) with carriage of any of the four loss-of-function variants, by 45% ( p < 10) for every allele inherited at Val279Phe, and by 2.7% ( p = 1.9 × 10) for every allele inherited at Val379Ala. Darapladib 160 mg once-daily reduced Lp-PLA activity by 65% ( p < 10). Causal risk ratios for coronary heart disease per 65% lower Lp-PLA activity were: 0.95 (0.88-1.03) with Val279Phe; 0.92 (0.74-1.16) with carriage of any loss-of-function variant; 1.01 (0.68-1.51) with Val379Ala; and 0.95 (0.89-1.02) with darapladib treatment. Conclusions In a large-scale human genetic study, none of a series of Lp-PLA-lowering alleles was related to coronary heart disease risk, suggesting that Lp-PLA is unlikely to be a causal risk factor.
Topics: 1-Alkyl-2-acetylglycerophosphocholine Esterase; Adult; Aged; Alleles; Benzaldehydes; Case-Control Studies; Coronary Disease; Female; Gene Expression Regulation; Genotype; Humans; Male; Middle Aged; Molecular Targeted Therapy; Oximes; Phospholipase A2 Inhibitors; Polymorphism, Single Nucleotide; Randomized Controlled Trials as Topic; Reference Values; Reproducibility of Results; Risk Assessment; Treatment Outcome
PubMed: 27940953
DOI: 10.1177/2047487316682186 -
Frontiers in Plant Science 2020Currently, a global analysis of the information available on the relative composition of the floral scents of a very diverse variety of plant species is missing. Such...
Currently, a global analysis of the information available on the relative composition of the floral scents of a very diverse variety of plant species is missing. Such analysis may reveal general patterns on the distribution and dominance of the volatile compounds that form these mixtures, and may also allow measuring the effects of factors such as the phylogeny, pollination vectors, and climatic conditions on the floral scents of the species. To fill this gap, we compiled published data on the relative compositions and emission rates of volatile organic compounds (VOCs) in the floral scents of 305 plant species from 66 families. We also gathered information on the groups of pollinators that visited the flowers and the climatic conditions in the areas of distribution of these species. This information allowed us to characterize the occurrence and relative abundances of individual volatiles in floral scents and the effects of biotic and climatic factors on floral scent. The monoterpenes trans-β-ocimene and linalool and the benzenoid benzaldehyde were the most abundant floral VOCs, in both ubiquity and predominance in the floral blends. Floral VOC richness and relative composition were moderately preserved traits across the phylogeny. The reliance on different pollinator groups and the climate also had important effects on floral VOC richness, composition, and emission rates of the species. Our results support the hypothesis that key compounds or compounds originating from specific biosynthetic pathways mediate the attraction of the main pollinators. Our results also indicate a prevalence of monoterpenes in the floral blends of plants that grow in drier conditions, which could link with the fact that monoterpene emissions protect plants against oxidative stresses throughout drought periods and their emissions are enhanced under moderate drought stress. Sesquiterpenes, in turn, were positively correlated with mean annual temperature, supporting that sesquiterpene emissions are dominated mainly by ambient temperature. This study is the first to quantitatively summarise data on floral-scent emissions and provides new insights into the biotic and climatic factors that influence floral scents.
PubMed: 32849712
DOI: 10.3389/fpls.2020.01154