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1.
Eur Respir J ; 60(4)2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35604814

RESUMO

PURPOSE: To investigate the correlations between densitometric and Computer Aided Lung Informatics for Pathology Evaluation and Rating (CALIPER)-derived indices of pulmonary emphysema and their change in the short-term period for groups of patients with different smoking habits. METHOD: This retrospective study included 284 subjects from the ITALUNG trial (198 men and 86 women; mean±sd age 60±4 years) who underwent low-dose chest computed tomography at baseline and 2-year follow-up. Subjects were divided into four groups (persistent smokers, restarters, quitters and former smokers) according to their smoking habit at baseline and follow-up. Densitometric and texture analyses were performed, using CALIPER software. A correlation analysis was conducted between CALIPER-derived low-attenuation areas (LAAs) and densitometric indices, including the 15th percentile of the whole-lung attenuation histogram (Perc15) and the relative areas with density ≤-950 HU (RA950). Densitometric indices and LAAs were evaluated at baseline and variation assessed longitudinally with comparisons between groups with different smoking habit. Further analysis of parenchymal changes per pulmonary zone was performed. RESULTS: LAAs were strongly correlated with Perc15 (rs=0.81; p<0.001) and RA950 (rs=0.905; p<0.001). At baseline, the group of smokers showed higher Perc15, lower RA950, lower LAAs (particularly mild sub-class of LAAs) than the group of ex-smokers (p<0.001). At 2-year follow-up, densitometric indices and LAAs increased in persistent smokers, former smokers and quitters (p<0.05). The progression was larger and statistically more significant in quitters (p<0.001). CONCLUSION: CALIPER texture analysis provides an objective measure comparable to traditional density/histogram features to assess the lung parenchymal changes in relation to different smoking habits.


Assuntos
Pulmão , Enfisema Pulmonar , Feminino , Humanos , Pulmão/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fumar/efeitos adversos , Tomografia Computadorizada por Raios X/métodos
2.
J Sci Food Agric ; 102(4): 1736-1743, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34403496

RESUMO

BACKGROUND: Bread represents a significant share of food waste worldwide. The extension of the bread shelf life together with innovative systems of food waste treatment might decrease waste biomass decay, the need for transportation, and the need for storage. In recent years, insects have been selected as a valuable tool for food waste treatment owing to their capability to transform low-value food waste into biomass with high nutritional value. Bakery wastes can be used profitably for this purpose. This work had two objectives: (i) to measure the impact of flaxseed cake fortification on bread shelf life depending on the leavening agent (baker's yeast vs sourdough); (ii) to evaluate the possible reuse of the stale bread fortified with flaxseed cake for Tenebrio molitor rearing. RESULTS: Our results showed that fortification seemed to slow the hardening rate of bread, particularly if baker's yeast was used. The time necessary for mold to appear in sourdough bread doubled (from 2 to 4 days). The addition of flaxseed cake to the recipe determined an increase of its scrap consumption by T. molitor larvae. We also observed a significant increase in the body mass of the T. molitor larvae fed with bread obtained with the brewer's yeast with respect to larvae fed with the sourdough. CONCLUSION: Taken together, these preliminary data can indicate that sourdough bread fortified with 5% of flaxseed cake can represent a promising tool to reduce food waste and to recycle bread scraps by a novel zero-waste approach. © 2021 Society of Chemical Industry.


Assuntos
Linho , Eliminação de Resíduos , Tenebrio , Animais , Pão , Fermentação , Larva
3.
Environ Res ; 201: 111581, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34174255

RESUMO

Ozone (O3)-induced metabolic changes in leaves are relevant and may have several ecological significances. Here, variations in foliar chemistry of two poplar clones (Populus deltoides × maximowiczii, Eridano, and P. × euramericana, I-214) under a chronic O3 treatment (80 ppb, 5 h d-1 for 10 consecutive days) were investigated. The aim was to elucidate if leaf age and/or O3-sensitivity (considering Eridano and I-214 as O3-sensitive and O3-resistant, respectively) can affect suitability of poplar foliage for Chrysomela populi L. (Coleoptera Chrysomelidae), in terms of palatability. Comparing controls, only low amino acid (AA) contents were reported in Eridano [about 3- and 4-fold in mature and young leaves (ML and YL, respectively)], and all the investigated primary metabolites [i.e. water soluble carbohydrates (WSC), proteins (Prot) and AA] were higher in YL than in ML of I-214 (+23, +54 and + 20%, respectively). Ozone increased WSC only in YL of Eridano (+24%, i.e. highest values among samples; O3 effects are always reported comparing O3-treated plants with the related controls). A concomitant decrease of Prot was observed in both ML and YL of Eridano, while only in YL of I-214 (-41, -45 and -51%, respectively). In addition, O3 decreased AA in YL of Eridano and in ML of I-214 (-40 and -14%, respectively). Comparing plants maintained under charcoal-filtered air, total ascorbate (Asc) was lower in Eridano in both ML and YL (around -22%), and abscisic acid (ABA) was similar between clones; furthermore, higher levels of Asc were reported in YL than in ML of Eridano (+19%). Ozone increased Asc and ABA (about 2- and 3-fold, respectively) in both ML and YL of Eridano, as well as ABA in YL of I-214 (about 2-fold). Comparing leaves maintained under charcoal-filtered air, the choice feeding test showed that the 2nd instar larvae preferred YL, and the quantity of YL consumed was 9 and 4-fold higher than ML in Eridano and I-214, respectively. Comparing leaves exposed to O3-treatment, a significant feeding preference for YL disks was also observed, regardless of the clone. The no-choice feeding test showed that larval growth was slightly higher on untreated YL than on untreated ML (+19 and + 10% in Eridano and I-214, respectively). The body mass of larvae fed with O3-treated YL was also significantly higher than that of larvae fed with untreated YL (3- and 2-fold in Eridano and I-214). This study highlights that realistic O3 concentrations can significantly impact the host/insect interactions, a phenomenon dependent on leaf age and O3-sensitivity of the host.


Assuntos
Besouros , Poluentes Ambientais , Ozônio , Populus , Animais , Insetos
4.
J Invertebr Pathol ; 184: 107645, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34245776

RESUMO

The biocidal potential of Brevibacillus laterosporus against mosquitoes of major medical importance has been widely documented, but its effects on non-target invertebrates are still poorly known. In this study, we determined the lethal and sub-lethal effects of B. laterosporus strain UNISS 18, an entomopathogenic bacterium known for its effectiveness against synanthropic Diptera, on the larvae of the Asian tiger mosquito Aedes albopictus, a vector of several pathogens to humans. Moreover, we compared the larvicidal activity with the lethal action on the invasive snail Physella acuta and on two non-target water-dwelling species: the mayfly Cloeon dipterum, and the harlequin fly Chironomus riparius. B. laterosporus exhibited significant lethal effects on all the tested species with a concentration-dependent activity. However, the susceptibility varied among species, with a higher susceptibility of Ae. albopictus (LC50 = 0.16 × 107 spores mL-1) than the other species (LC50 = 0.31, 0.33, and 0.30 × 107 spores mL-1 for C. dipterum, C. riparius, and P. acuta, respectively). While 1st instar mosquito larvae were very susceptible to the bacterial infection, no effects on preimaginal development stages and adult emergence were observed at sub-lethal spores' concentrations. Even if the efficacy of B. laterosporus against Ae. albopictus and the invasive freshwater snail P. acuta is promising for their control, the susceptibility of non-target beneficial aquatic insects, highlights the need of accurate evaluations before applying B. laterosporus for pest management in water environments.


Assuntos
Aedes/microbiologia , Agentes de Controle Biológico/farmacologia , Agentes de Controle Biológico/toxicidade , Brevibacillus/fisiologia , Invertebrados/efeitos dos fármacos , Aedes/efeitos dos fármacos , Animais , Organismos Aquáticos/efeitos dos fármacos , Invertebrados/microbiologia
5.
Ecotoxicol Environ Saf ; 208: 111486, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33130481

RESUMO

The honeybee, Apis mellifera L. (Hymenoptera: Apidae), a keystone pollinator of wild plant species and agricultural crops, is disappearing globally due to parasites and diseases, habitat loss, genetic constraints, beekeeper management issues and to the widespread use of pesticides. Besides insecticides, widely studied in this species, honeybees are also exposed to herbicides and fungicides and heavy metals whose lethal and sublethal effects need to be investigated. In this context, our study aimed to evaluate the effects of fungicides and of heavy metals on honeybees and to develop and apply a multi-biomarker approach that include an Integrated Biological Index (IBRv2) to assess the toxicological status of this species. Biomarkers of neurotoxicity (AChE and CaE), metabolic alteration (ALP, and GST) and immune system (LYS, granulocytes) were measured, following honeybees' exposure to cadmium or to a crop fungicide, using the genotoxic compound EMS as positive control. A biomarker of genotoxicity (NA assay) was developed and applied for the first time in honeybees. At the doses tested, all the contaminants showed sublethal toxicity to the bees, highlighting in particular genotoxic effects. The data collected were analyzed by an IBRv2 index, which integrated the seven biomarkers used in this study. IBRv2 index increased with increasing cadmium or fungicide concentrations. The IBRv2 represents a simple tool for a general description of honeybees ecotoxicological health status. Results highlight the need for more in-depth investigations on the effects of fungicides on non-target organisms, such as honeybees, using sensitive methods for the determination of sublethal effects. This study contributes to the development of a multi-biomarker approach to be used for a more accurate ecotoxicological environmental monitoring of these animals.


Assuntos
Abelhas/efeitos dos fármacos , Biomarcadores/análise , Fungicidas Industriais/toxicidade , Metais Pesados/toxicidade , Testes de Toxicidade/métodos , Animais , Testes de Mutagenicidade/métodos
6.
Molecules ; 26(4)2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33572107

RESUMO

In developing countries, crop deterioration is mainly caused by inappropriate storage conditions that promote insect infestation. Synthetic pesticides are associated with serious adverse effects on humans and the environment. Thus, finding alternative "green" insecticides is a very pressing need. Calotropis procera (Aiton) Dryand (Apocynaceae) growing in Saudi Arabia was selected for this purpose. LC-MS/MS analysis was applied to investigate the metabolic composition of different C. procera extracts. Particularly, C. procera latex and leaves showed a high presence of cardenolides including calactin, uscharidin, 15ß-hydroxy-calactin, 16ß-hydroxy-calactin, and 12ß-hydroxy-calactin. The ovicidal activity of the extracts from different plant organs (flowers, leaves, branches, roots), and of the latex, against Cadra cautella (Walker) (Lepidoptera, Pyralidae) was assessed. Extracts of C. procera roots displayed the most potent activity with 50% of C. cautella eggs not hatching at 10.000 ppm (1%).


Assuntos
Calotropis/química , Óvulo/efeitos dos fármacos , Óvulo/fisiologia , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Animais , Flores/química , Látex/química , Mariposas , Folhas de Planta/química , Raízes de Plantas/química
7.
J Invertebr Pathol ; 177: 107493, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33132202

RESUMO

In order to increase our understanding of the insecticidal potential of the entomopathogenic bacterium Brevibacillus laterosporus strain UNISS 18 against insect pests, investigations were conducted on a selection of dipteran species including fruit flies, house flies, blow flies, and mosquitoes, characterized by adaptations to very diverse habitats. According to lethal concentration (LC50) values, the common house mosquito Culex pipiens (LC50 = 0.10 × 106 spores/mL) and the yellow fever mosquito Aedes aegypti (LC50 = 0.18 × 106 spores/mL) were significantly more susceptible than the flies. The blow flies were the second taxon in term of susceptibility to B. laterosporus spores, with a higher mortality in Calliphora vomitoria (LC50 = 78.84 × 106 spores/mL) than Lucilia caesar (LC50 = 148.30 × 106 spores/mL). The effectiveness of B. laterosporus spores was reduced by half in the house fly Musca domestica (LC50 = 82.41 × 106 spores/mL). The lowest susceptibility was observed in the fruit flies, among which the spotted wing drosophila (SWD), Drosophila suzukii, was the most susceptible (LC50 = 217.51 × 106 spores/mL) in comparison with the medfly Ceratitis capitata and the olive fly Bactrocera oleae (LC50 = 2567.32 and 2567.36 × 106 spores/mL, respectively). The present study demonstrated that significantly different degrees of susceptibility are associated with diverse dipteran species including plant and animal parasites, and we suggest that B. laterosporus established different relationships with dipteran species in different ecosystems.


Assuntos
Agentes de Controle Biológico/farmacologia , Brevibacillus/química , Dípteros , Controle Biológico de Vetores , Animais , Dípteros/microbiologia , Controle de Insetos , Inseticidas/farmacologia
8.
J Invertebr Pathol ; 174: 107391, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32416086

RESUMO

Blowfly, Lucilia sericata (Diptera: Calliphoridae), is a problematic synanthropic insect pest, a vector of microbial pathogens, and the causal agent of secondary myiasis. Fungal biopesticides are considered eco-friendly tools, alternative to synthetic pesticides, for the control of arthropod pests; however, to date, little is known about their bioactivity against blowflies. In this study, we assessed the insecticidal activity of three well-known entomopathogenic fungi, Beauveria bassiana, Beauveria pseudobassiana and Akanthomyces muscarius against L. sericata. In addition, we tested powdered carnauba wax as an electrically charged dust carrier in an attempt to enhance the virulence of fungal spores. Pathogenicity tests on adult flies, by adult immersion in conidial suspension (108 conidia mL-1), showed that the median lethal time (LT50) was 5.3, 5.9, and 6.2 days for B. bassiana, A. muscarius and B. pseudobassiana, respectively. In topical tests, when 108 dry conidia were mixed with or without carnauba wax, the LT50 was 7.7, 10.2, and 14 days without this carrier and 6.9, 8.6, and 13.8 days with it for B. bassiana, B. pseudobassiana and A. muscarius, respectively. Overall, our findings showed that, among the tested fungi, B. bassiana was the most virulent when formulated as a dry powder with carnauba wax, which greatly improved fungal efficacy against the blowfly. We discuss the utility of carnauba wax for electrostatic formulation powder of fungal spores in the integrated management of blowflies as an environmentally sustainable tool to reduce the over-reliance on chemical insecticides and their risk of resistance.


Assuntos
Beauveria/patogenicidade , Agentes de Controle Biológico/farmacologia , Calliphoridae , Hypocreales/patogenicidade , Controle Biológico de Vetores , Ceras/farmacologia , Animais , Inseticidas/farmacologia , Esporos Fúngicos/patogenicidade
9.
Molecules ; 25(9)2020 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-32397385

RESUMO

: The present work evaluates for the first time two Lavandin (Lavandula × intermedia Emeric ex Loisel.) aromatic waters obtained from different plant organs, the flowers and the stems. Both extracts were analysed by GC-MS, which indicates semi-quantitative differences between the major metabolites including linalool, 1,8-cineole, camphor, linalyl acetate and 4-terpineol. 1H-NMR and LC-MS investigation confirmed the presence of these compounds. Moreover, behavioural tests with the food insect pest Tribolium confusum (Coleoptera Tenebrionidae) showed a good repellency for both hydrosols extracts with RD50 values of 3.6 and 3.3 µL cm-2 for the flowers and stems, respectively; at the higher concentrations, however, the hydrosol extract from the flowers is expected to be more effective than the one from the stems. The effect of the flowers and stems aromatic water of Lavandin on seed germination of Raphanus sativus was also evaluated. Results showed that seed germination was completely inhibited by flowers hydrolate, having a possible application as natural herbicide. The overall experience with these Lavandin extracts indicates the potential of improved hydrolates to become the main distillation products, rather than by-products, of the aromatic plants manufacturing; this stimulates further discussions about the potential positive impacts that such a shift could have in the context of ecopharmacognosy.


Assuntos
Repelentes de Insetos/farmacologia , Lavandula/química , Extratos Vegetais/farmacologia , Tribolium/fisiologia , Monoterpenos Acíclicos/química , Monoterpenos Acíclicos/farmacologia , Animais , Cânfora/química , Cânfora/farmacologia , Eucaliptol/química , Eucaliptol/farmacologia , Flores/química , Cromatografia Gasosa-Espectrometria de Massas , Germinação , Repelentes de Insetos/química , Itália , Mentol/análogos & derivados , Mentol/química , Mentol/farmacologia , Monoterpenos/química , Monoterpenos/farmacologia , Óleos Voláteis , Extratos Vegetais/química , Óleos de Plantas , Caules de Planta/química , Raphanus/fisiologia
10.
Parasitol Res ; 114(1): 227-36, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25327954

RESUMO

Neem seed oil (NSO) of Azadirachta indica (Meliaceae) contains more than 100 determined biologically active compounds, and many formulations deriving from them showed toxicity, antifeedancy and repellence against a number of arthropod pests. However, it is widely known that botanical products can differ in their chemical composition and bioactivity, as function of the production site and production process. We used high-performance thin layer chromatography (HPTLC) to investigate differences in chemical constituents of NSOs from three production sites. HPTLC analyses showed several differences in chemical abundance and diversity among NSOs, with special reference to limonoids. Furthermore, the three NSOs and their fractions of increasing polarities [i.e. ethyl acetate (EA) fraction and butanol (BU) fraction] were evaluated for larvicidal toxicity and field oviposition deterrence against the Asian tiger mosquito, Aedes albopictus, currently the most invasive mosquito worldwide. Results from bioactivity experiments showed good toxicity of NSOs and EA fractions against A. albopictus fourth instar larvae (with LC50 values ranging from 142.28 to 209.73 ppm), while little toxicity was exerted by BU fractions. A significant effect of the production site and dosage was also found and is probably linked to differences in abundance of constituents among samples, as highlighted by HPTLC analyses. NSOs and EAs were also able to deter A. albopictus oviposition in the field (effective repellence values ranging from 98.55 to 70.10%), while little effectiveness of BU fractions was found. Concerning ovideterrent activity, no difference due to the production site was found. This is the first report concerning larvicidal toxicity of NSO against A. albopictus and ovideterrence against Culicidae in the field. The chance to use chemicals from the NSO EA fraction seems promising, since they are effective at lower doses, if compared to synthetic products currently marketed, and could be an advantageous alternative to build newer and safer mosquito control tools.


Assuntos
Aedes/efeitos dos fármacos , Azadirachta/química , Glicerídeos/farmacologia , Controle de Mosquitos/métodos , Oviposição/efeitos dos fármacos , Terpenos/farmacologia , Animais , Cromatografia em Camada Fina , Feminino , Filariose , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Limoninas/farmacologia , Inquéritos e Questionários
11.
Parasitol Res ; 114(2): 391-7, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25563612

RESUMO

Mosquitoes (Diptera: Culicidae) represent an important threat to millions of people worldwide, since they act as vectors for important pathogens, such as malaria, yellow fever, dengue and West Nile. Control programmes mainly rely on chemical treatments against larvae, indoor residual spraying and insecticide-treated bed nets. In recent years, huge efforts have been carried out to propose new eco-friendly alternatives, with a special focus on the evaluation of plant-borne mosquitocidal compounds. Major examples are neem-based products (Azadirachta indica A. Juss, Meliaceae) that have been proven as really effective against a huge range of pests of medical and veterinary importance, including mosquitoes. Recent research highlighted that neem cake, a cheap by-product from neem oil extraction, is an important source of mosquitocidal metabolites. In this review, we examined (i) the latest achievements about neem cake metabolomics with special reference to nor-terpenoid and related content; (ii) the neem cake ovicidal, larvicidal and pupicidal toxicity against Aedes, Anopheles and Culex mosquito vectors; (iii) its non-target effects against vertebrates; and (iv) its oviposition deterrence effects on mosquito females. Overall, neem cake can be proposed as an eco-friendly and low-cost source of chemicals to build newer and safer control tools against mosquito vectors.


Assuntos
Azadirachta/química , Culicidae/efeitos dos fármacos , Glicerídeos/farmacologia , Inseticidas/farmacologia , Oviposição/efeitos dos fármacos , Extratos Vegetais/farmacologia , Terpenos/farmacologia , Animais , Culicidae/anatomia & histologia , Feminino , Glicerídeos/isolamento & purificação , Inseticidas/isolamento & purificação , Larva/efeitos dos fármacos , Extratos Vegetais/isolamento & purificação , Terpenos/isolamento & purificação
12.
Parasitol Res ; 114(3): 1011-21, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25563605

RESUMO

Mosquitoes (Diptera: Culicidae) represent a threat for millions of people worldwide, since they act as vectors for important pathogens, including malaria, yellow fever, dengue and West Nile. Second to malaria as the world's most widespread parasitic disease, infection by trematodes is a devastating public health problem. In this study, we proposed two essential oils from plants cultivated in Mediterranean regions as effective chemicals against mosquitoes and freshwater snails vectors of Echinostoma trematodes. Chemical composition of essential oils from Achillea millefolium (Asteraceae) and Haplophyllum tuberculatum (Rutaceae) was investigated. Acute toxicity was evaluated against larvae of the West Nile vector Culex pipiens (Diptera: Culicidae) and the invasive freshwater snail Physella acuta (Mollusca: Physidae), an important intermediate host of many parasites, including Echinostoma revolutum (Echinostomidae). Acute toxicity of essential oils was assessed also on a non-target aquatic organism, the mayfly Cloeon dipterum (Ephemeroptera: Baetidae). Achillea millefolium and H. tuberculatum essentials oils were mainly composed by oxygenated monoterpenes (59.3 and 71.0 % of the whole oil, respectively). Chrysanthenone and borneol were the two major constituents of Achillea millefolium essential oil (24.1 and 14.2 %, respectively). Major compounds of H. tuberculatum essential oil were cis-p-menth-2-en-1-ol and trans-p-menth-2-en-1-ol (22.9 and 16.1 %, respectively). In acute toxicity assays, C. pipiens LC50 was 154.190 and 175.268 ppm for Achillea millefolium and H. tuberculatum, respectively. P. acuta LC50 was 112.911 and 73.695 ppm for Achillea millefolium and H. tuberculatum, respectively, while the same values were 198.116 and 280.265 ppm for C. dipterum. Relative median potency analysis showed that both tested essential oils were more toxic to P. acuta over C. dipterum. This research adds knowledge on plant-borne chemicals toxic against invertebrates of medical importance, allowing us to propose the tested oils as effective candidates to develop newer and safer vector control tools.


Assuntos
Culex/efeitos dos fármacos , Echinostoma/efeitos dos fármacos , Ephemeroptera/efeitos dos fármacos , Gastrópodes/efeitos dos fármacos , Óleos Voláteis/toxicidade , Animais , Culicidae/efeitos dos fármacos , Gastrópodes/parasitologia , Larva/efeitos dos fármacos , Dose Letal Mediana , Região do Mediterrâneo , Monoterpenos/isolamento & purificação , Monoterpenos/toxicidade , Óleos Voláteis/química
13.
Parasitol Res ; 113(5): 1813-20, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24599300

RESUMO

Mosquito repellents represent a cleaner and safer alternative for population control and reduce the diseases they carry in large areas of the world. Recently, research has been focused on repellents of natural origins, both crude essential oils and their main constituents. We have observed that, although a large number of compounds can be efficiently used as mosquito repellents, their efficacy is never higher than those of commercial products DEET and Icaridin. Reasoning that probably specific and exceptionally active repellents might not exist, we focused our research on products that could provide longer protection times with respect to current commercial formulations while being used at lower concentrations. Based on the structure of menthone, a moderate natural repellent, we designed and synthesised some cyclic ketals that, because of their reduced volatility, could be effective for longer periods. In particular, a 1% solution of one of such derivatives can still reduce mosquito bites by 90% after 2 h, while DEET provides the same performance only for 15 min, when used at the same concentration. The approach we illustrate can be applied to other compounds and other systems and offers the additional advantage that derivatives of reduced volatility are also endowed with weaker odours.


Assuntos
Culicidae , Mordeduras e Picadas de Insetos/prevenção & controle , Repelentes de Insetos/química , Mentol/química , Animais , DEET/química , Humanos , Estrutura Molecular , Odorantes , Óleos Voláteis/química , Óleos de Plantas/química
14.
Parasitol Res ; 113(3): 933-40, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24337544

RESUMO

Industrial plant-borne by-products can be sources of low-cost chemicals, potentially useful to build eco-friendly control strategies against mosquitoes. Neem cake is a cheap by-product of neem oil extraction obtained by pressing the seeds of Azadirachta indica. Neem products are widely used as insecticides since rarely induce resistance because their multiple mode of action against insect pests and low-toxicity rates have been detected against vertebrates. In this research, we used field bioassays to assess the effective oviposition repellence of neem cake fractions of increasing polarity [n-hexane (A), methanol (B), ethyl acetate (C), n-butanol (D), and aqueous (E) fraction] against Aedes albopictus, currently the most invasive mosquito worldwide. These fractions, already characterized for low nortriterpenoids contents by HPLC analyses, were analyzed for their total content by HPTLC, highlighting striking differences in their chemical composition. Field results showed that B, A, and C tested at 100 ppm exerted higher effective repellence over the control (71.33, 88.59, and 73.49% of ER, respectively), while E and D did not significantly deter A. albopictus oviposition (17.06 and 22.72% of ER, respectively). The highest oviposition activity index was achieved by A (-0.82), followed by C (-0.63), and B (-0.62). Lower OAIs were achieved by D (-0.14) and E (-0.09). On the basis of our results, we believe that A, B, and C are very promising as oviposition deterrents against the arbovirus vector A. albopictus since they are proved as rich in active metabolites, cheap, and really effective at low doses.


Assuntos
Aedes/efeitos dos fármacos , Arbovírus , Azadirachta/química , Inseticidas/farmacologia , Oviposição/efeitos dos fármacos , Animais , Fracionamento Químico , Cromatografia Líquida de Alta Pressão , Feminino , Insetos Vetores/efeitos dos fármacos , Inseticidas/química , Larva/efeitos dos fármacos
15.
Parasitol Res ; 113(1): 251-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24146210

RESUMO

In latest years, the importance of the Melaleuca alternifolia essential oil (EO) has been greatly empathised due to its anti-microbial and anti-inflammatory effects, as well as to its toxic properties towards many arthropods of great medical and veterinary importance. In this research, the EO extracted from aerial parts of M. alternifolia was evaluated for its toxicity against larvae of the most invasive mosquito worldwide, Aedes albopictus (Diptera: Culicidae), and towards adults of the water flea, Daphnia magna (Cladocera: Crustacea), a non-target aquatic organism that share the same ecological niche of A. albopictus. The chemical composition of M. alternifolia EO was investigated by GC-MS analysis. Tea tree EO was mainly composed by oxygenated monoterpenes, with 1,8-cineole as the major constituent. M. alternifolia EO exerted toxic activity against A. albopictus larvae, with a LC50 = 267.130 ppm. However, this EO had a remarkable acute toxicity also towards adults of the non-target arthropod D. magna, with a LC50 = 80.636 ppm. This research provide useful information for the development of newer and safer mosquito control tools, highlighting that the non-target effects against aquatic organisms that share the same ecological niche of A. albopictus larvae are crucial in the development of ecofriendly mosquito control strategies. Further research is needed to investigate the chronic and/or reproductive toxicity of M. alternifolia EO both towards target and non-target aquatic arthropods.


Assuntos
Daphnia/efeitos dos fármacos , Inseticidas/toxicidade , Óleo de Melaleuca/toxicidade , Aedes/efeitos dos fármacos , Animais , Organismos Aquáticos/efeitos dos fármacos , Cicloexanóis/química , Eucaliptol , Cromatografia Gasosa-Espectrometria de Massas , Inseticidas/química , Larva/efeitos dos fármacos , Monoterpenos/química , Controle de Mosquitos , Óleo de Melaleuca/química , Testes de Toxicidade Aguda
16.
Insects ; 15(2)2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38392552

RESUMO

Hermetia illucens is a species of great interest for numerous industrial applications. A high-quality reference genome is already available for H. illucens. However, the worldwide maintenance of numerous captive populations of H. illucens, each with its own genotypic and phenotypic characteristics, made it of interest to perform a de novo genome assembly on one population of H. illucens to define a chromosome-scale genome assembly. By combining the PacBio and the Omni-C proximity ligation technologies, a new H. illucens chromosome-scale genome of 888.59 Mb, with a scaffold N50 value of 162.19 Mb, was assembled. The final chromosome-scale assembly obtained a BUSCO completeness of 89.1%. By exploiting the Omni-C proximity ligation technology, topologically associated domains and other topological features that play a key role in the regulation of gene expression were identified. Further, 65.62% of genomic sequences were masked as repeated sequences, and 32,516 genes were annotated using the MAKER pipeline. The H. illucens Lsp-2 genes that were annotated were further characterized, and the three-dimensional organization of the encoded proteins was predicted. A new chromosome-scale genome assembly of good quality for H. illucens was assembled, and the genomic annotation phase was initiated. The availability of this new chromosome-scale genome assembly enables the further characterization, both genotypically and phenotypically, of a species of interest for several biotechnological applications.

17.
Foods ; 13(2)2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38254579

RESUMO

The use of food waste as a rearing substrate to grow insects is an ecofriendly and sustainable alternative to food waste disposal. In the present research, Hermetia illucens prepupae were reared with a standard diet, different food waste-based diets based on vegetables, fruits, and meat, and a mixed one, where the previous three components were present equally. The demineralization and deproteination of the prepupae allowed for the obtainment of chitin that was then deacetylated to produce chitosan. Also, the bleaching of chitosan was attempted for further purification. The yield of the different reactions was investigated, and the infrared spectra of the obtained materials were analyzed to obtain information on the quantity and acetylation degree trend of the chitin and chitosan as a function of the diet. The possibility to slightly modulate the yield and acetylation degree of both biopolymers thanks to the specific diet was enlightened. Interestingly, the standard diet resulted in the highest fraction of chitin having the highest acetylation degree, and in the highest fraction of chitosan having the lowest acetylation degree.

18.
Environ Sci Pollut Res Int ; 31(25): 37366-37375, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38772995

RESUMO

Recently, much research has been oriented towards the influence of different food wastes and agricultural by-products on the final larval biomass and chemical composition of the insect species Hermetia illucens L. (Diptera: Stratiomyidae). However, there is a gap in the literature regarding the possible relationship between the feeding substrate of H. illucens larvae and chitin. In this context, in the present study, larvae of H. illucens derived from two populations (i.e., UNIPI and UTH), were reared on different diets composed of fruits, vegetables, and meat. Based on the results, the larval survival was high for all diets tested. Larval growth in terms of weight gain, larval length, and feed conversion ratio (FCR) depended on the composition of each diet. The chitin and chitosan composition of larvae, reared on different substrates, did not reveal significant differences. Given the fact that the feeding substrate represent a significant cost in the industrial production of insects, its correlation with a high value product (i.e. chitosan) is important. On the other hand, as the prepupal stage of H. illucens is currently used as animal feed, the metabolization of chitin by farmed animals when the larvae or prepupae were offered as feed could have adverse effects. Thus, depending on the final product that is to be produced, industries could benefit from the establishment of a suitable diet.


Assuntos
Ração Animal , Quitina , Quitosana , Dieta , Dípteros , Larva , Pupa , Animais , Larva/crescimento & desenvolvimento , Pupa/crescimento & desenvolvimento
19.
Eur J Surg Oncol ; 50(6): 108306, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38603866

RESUMO

INTRODUCTION: Mutations in the BRAF gene (BRAFmut) are associated with an unfavorable prognosis in patients with metastatic colorectal cancer (CRC). The aim of this meta-analysis was to evaluate the prognosis of colorectal cancer (CRC) patients with liver metastases and the potential benefits of liver resection in patients with BRAFmut CRC. MATERIAL AND METHODS: A systematic search of PubMed, Cochrane Central Controlled Trials, and Embase databases was conducted on May 31, 2023. The inclusion criteria were as follows:1) reporting of outcomes in patients with BRAFmut CRC who underwent surgery for liver metastases and/or comparison of outcomes between those who underwent and those who did not undergo resection; 2) reporting of survival information as hazard ratios (HR); and 3) publication in English. RESULTS: 34 studies were included. Median follow up was 48 months for prognostic BRAF status meta-analysis. BRAFmut status showed a significantly increased risk of mortality (hazard ratio [HR] = 2.56, 95% confidence interval [CI] 2.04-3.22; P < 0.01) and relapse (HR = 1.97, 95% CI 1.44-2.71; P < 0.01). Resection of liver metastases was associated with a survival benefit (median follow up 46 months). The HR for survival was 0.44 (95% confidence interval [CI] 0.33-0.59; P < 0.01) in favor of surgery. CONCLUSIONS: and Relevance: Our analysis indeed confirms that BRAF mutation is associated with poor survival outcomes after liver resection of CRC metastases. However, upon quantitatively assessing the survival benefit of surgical intervention in patients with BRAF-mutated CRC liver metastases, we identified a significant 56% reduction in the risk of death.


Assuntos
Neoplasias Colorretais , Hepatectomia , Neoplasias Hepáticas , Mutação , Proteínas Proto-Oncogênicas B-raf , Humanos , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Colorretais/patologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/cirurgia , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/genética , Prognóstico , Taxa de Sobrevida
20.
Parasitol Res ; 112(3): 1155-61, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23263388

RESUMO

The essential oils of many Apiaceae species have been already studied for their insecticidal and repellent properties against insect pests. In this research, the essential oil (EO) extracted from the fruits of Coriandrum sativum L. (Apiaceae) was evaluated for the first time for its larvicidal and repellent activities against the most invasive mosquito worldwide, Aedes albopictus Skuse (Diptera: Culicidae). The chemical composition of C. sativum EO was investigated by gas chromatography with electron impact mass spectrometry analysis. Coriander EO was mainly composed by monoterpene hydrocarbons and oxygenated monoterpenes, with linalool (83.6 %) as the major constituent. C. sativum EO exerted toxic activity against A. albopictus larvae: LC(50) was 421 ppm, while LC(90) was 531.7 ppm. Repellence trials highlighted that C. sativum EO was a good repellent against A. albopictus, also at lower dosages: RD(50) was 0.0001565 µL/cm(2) of skin, while RD(90) was 0.002004 µL/cm(2). At the highest dosage (0.2 µL/cm(2) of skin), the protection time achieved with C. sativum essential oil was higher than 60 min. This study adds knowledge about the chemical composition of C. sativum EO as well as to the larvicidal and repellent activity exerted by this EO against A. albopictus. On this basis, we believe that our findings could be useful for the development of new and safer products against the Asian tiger mosquito.


Assuntos
Aedes/efeitos dos fármacos , Coriandrum/química , Repelentes de Insetos/farmacologia , Inseticidas/farmacologia , Óleos Voláteis/farmacologia , Animais , Bioensaio , Vetores de Doenças , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Repelentes de Insetos/química , Repelentes de Insetos/isolamento & purificação , Inseticidas/química , Inseticidas/isolamento & purificação , Larva/efeitos dos fármacos , Masculino , Óleos Voláteis/isolamento & purificação , Análise de Sobrevida
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