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1.
Pest Manag Sci ; 78(8): 3489-3497, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35567400

RESUMO

BACKGROUND: Rusts and powdery mildews are severe fungal diseases of major crops worldwide, including cereals and legumes. They can be managed by chemical fungicide treatments, with negative consequences as environmental pollution and risk for human and animal health. Bioactive natural products could be the safest alternative for pest control. The family of anthraquinones, as well as analogue compounds containing an anthraquinone moiety or some modified anthraquinone rings, has been reported to exhibit certain antibiotic activity. Thus, the potential antifungal activity of some anthraquinones isolated from Ascochyta lentis, was assayed in this study for their effectiveness to reduce rust and powdery mildew diseases on pea and oat. Their effect on fungal development was macro- and microscopically assessed on inoculated leaves, and compared to the control achieved by the chemical fungicide (Tetraconazol 12.5% and Azoxystrobin 25%). In addition, the most promising compound was also tested at different concentrations in inoculated whole plants in order to evaluate its preventive and curative potential against fungal infection. RESULTS: All metabolites studied strongly reduced the development of rust and powdery mildews in both pea and oat, being pachybasin and lentiquinone C the most effective ones in hampering fungal spore germination and appressoria formation. Some of them also affected post-penetration events reducing colony size and number of haustoria per colony. Results were confirmed for pachybasin in whole plants assays, showing an efficacy similar to the commercial fungicide to control fungal diseases, both in preventive and curative applications. CONCLUSIONS: Some fungal anthraquinones and close metabolites, especially pachybasin, could be very promising molecules with effective potential as antifungal agents against both rust and powdery mildew of both pea and oat. Some structure activity-relationships feature have also been evaluated. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Basidiomycota , Fungicidas Industriais , Micoses , Antraquinonas/farmacologia , Antifúngicos/farmacologia , Fungicidas Industriais/farmacologia , Humanos , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle
2.
Phys Med ; 91: 28-42, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34710789

RESUMO

PURPOSE: The assessment of low-contrast-details is a part of the quality control (QC) program in digital radiology. It generally consists of evaluating the threshold contrast (Cth) detectability details for different-sized inserts, appropriately located in dedicated QC test tools. This work aims to propose a simplified method, based on a statistical model approach for threshold contrast estimation, suitable for different modalities in digital radiology. METHODS: A home-madelow-contrast phantom, made of a central aluminium insert with a step-wedge, was assembled and tested. The reliability and robustness of the method were investigated for Mammography, Digital Radiography, Fluoroscopy and Angiography. Imageswere analysed using our dedicated software developed on Matlab®. TheCth is expressed in the same unit (mmAl) for all studied modalities. RESULTS: This method allows the collection of Cthinformation from different modalities and equipment by different vendors, and it could be used to define typical values. Results are summarized in detail. For 0.5 diameter detail, Cthresults are in the range of: 0.018-0.023 mmAl for 2D mammography and 0.26-0.34 mmAl DR images. For angiographic images, for 2.5 mm diameter detail, the Cths median values are 0.55, 0.4, 0.06, 0.12 mmAl for low dose fluoroscopy, coronary fluorography, cerebral and abdominal DSA, respectively. CONCLUSIONS: The statistical method proposed in this study gives a simple approach for Low-Contrast-Details assessment, and the typical values proposed can be implemented in a QA program for digital radiology modalities.


Assuntos
Mamografia , Intensificação de Imagem Radiográfica , Imagens de Fantasmas , Controle de Qualidade , Reprodutibilidade dos Testes
3.
Nat Prod Res ; 35(21): 3977-3984, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32290692

RESUMO

An investigation of the secondary metabolites was carried out on Thymelaea hirsuta collected from Lampedusa, the largest island of the Pelagie archipelago, located about 100 km from the North African coast and 200 km from the coast of Sicily. Ten compounds were isolated and found to belong to different classes of natural products as chromenes, cyclohexanones, furanyl, bis-furanyl and furanone polyphenols, and acrylates. Compounds 7, 8, 9 and 10 were slightly phytotoxic to lettuce reaching phytotoxicity of 1 (7, 8 and 9) and 2 (10) using a 1-5 point scale. None of the compounds were active against Agrostis stolonifera L., a perennial grass of the Poaceae family. Tested against three Colletotrichum species (C. acutatum, C. fragarie and C. gloeosporioides) pathogenic for agricultural plants, only compound 6 had activity against all three species, but it was not as active as captan, the commercial fungicide used as a positive control.


Assuntos
Agrostis , Colletotrichum , Thymelaeaceae , Lactuca , Extratos Vegetais
4.
Mycologia ; 112(3): 533-542, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32330111

RESUMO

COLLETOTRICHUM LUPINI: is the causal agent of lupin (Lupinus albus L.) anthracnose, a destructive seed-borne disease affecting stems and pods. Despite that several biological studies have been carried out on this pathogen, the production of secondary metabolites has not yet been investigated. Thus, a strain of C. lupini, obtained from symptomatic stems of L. albus, has been grown in vitro to evaluate its ability to produce bioactive compounds. From its culture filtrates, a 3-substituted indolinone, named lupindolinone, and a 5,6-disubstituted tetrahydro-α-pyrone, named lupinlactone, were isolated together with the known (3R)-mevalonolactone and tyrosol. Lupindolinone and lupinlactone were characterized as 3-ethylindolin-2-one and 5-hydroxy-6-methyltetrahydropyran-2-one by spectroscopic methods (essentially nuclear magnetic resonance [NMR] and high-resolution electrospray ionization mass spectrometry [HR ESI-MS]). The R absolute configuration (AC) at C-5 of lupinlactone was determined by applying the modified Mosher's method. Thus, considering its relative stereochemistry assigned by NMR spectroscopy, the AC of lupinlactone could be formulated as 5R,6S. Lupindolinone was isolated as racemic mixture as shown by investigation using chiroptical methods. The metabolites were assayed in different biological tests and proved to have some activities at the used concentration.


Assuntos
Colletotrichum/metabolismo , Alcaloides Indólicos/análise , Lupinus/parasitologia , Doenças das Plantas , Metabolismo Secundário/fisiologia , Estrutura Molecular
5.
Toxins (Basel) ; 12(2)2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-32085485

RESUMO

Six phytotoxins were obtained from the culture filtrates of the ascomycete Neofusicoccum batangarum, the causal agent of the scabby canker of cactus pear (Opuntia ficus-indica L.) in minor Sicily islands. The phytotoxins were identified as (-)-(R)-mellein (1); (±)-botryoisocoumarin A (2); (-)-(3R,4R)- and (-)-(3R,4S)-4-hydroxymellein (3 and 4); (-)-terpestacin (5); and (+)-3,4-dihydro-4,5,8-trihydroxy-3-methylisocoumarin, which we named (+)-neoisocoumarin (6). This identification was done by comparing their spectral and optical data with those already reported in literature. The absolute configuration (3R,4S) to (+)-neoisocoumarin (6) was determined using the advanced Mosher method. All six metabolites were shown to have phytotoxicity on the host (cactus pear) and non-host (tomato) plants, and the most active compounds were (±)-botryoisocoumarin A (2), (-)-terpestacin (5), and (+)-neoisocoumarin (6).


Assuntos
Ascomicetos/metabolismo , Frutas/microbiologia , Micotoxinas/isolamento & purificação , Opuntia/microbiologia , Doenças das Plantas/microbiologia , Ascomicetos/patogenicidade , Estrutura Molecular , Micotoxinas/química , Ressonância Magnética Nuclear Biomolecular
6.
Molecules ; 24(13)2019 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-31261896

RESUMO

Ceratitis capitata, the Mediterranean fruit fly, is one of the most serious agricultural pests worldwide responsible for significant reduction in fruit and vegetable yields. Eradication is expensive and often not feasible. Current control methods include the application of conventional insecticides, leading to pesticide resistance and unwanted environmental effects. The aim of this study was to identify potential new attractants for incorporation into more environmentally sound management programs for C. capitata. In initial binary choice bioassays against control, a series of naturally occurring plant and fungal aromatic compounds and their related analogs were screened, identifying phenyllactic acid (7), estragole (24), o-eugenol (21), and 2-allylphenol (23) as promising attractants for male C. capitata. Subsequent binary choice tests evaluated five semisynthetic derivatives prepared from 2-allylphenol, but none of these were as attractive as 2-allylphenol. In binary choice bioassays with the four most attractive compounds, males were more attracted to o-eugenol (21) than to estragole (24), 2-allylphenol (23), or phenyllactic acid (7). In addition, electroantennography (EAG) was used to quantify antennal olfactory responses to the individual compounds (1-29), and the strongest EAG responses were elicited by 1-allyl-4-(trifluoromethyl)benzene (11), estragole (24), 4-allyltoluene (14), trans-anethole (9), o-eugenol (21), and 2-allylphenol (23). The compounds evaluated in the current investigation provide insight into chemical structure-function relationships and help direct future efforts in the development of improved attractants for the detection and control of invasive C. capitata.


Assuntos
Alcaloides/farmacologia , Ceratitis capitata/fisiologia , Controle de Insetos/métodos , Derivados de Alilbenzenos , Animais , Anisóis/farmacologia , Antenas de Artrópodes/efeitos dos fármacos , Antenas de Artrópodes/fisiologia , Ceratitis capitata/efeitos dos fármacos , Eugenol/farmacologia , Lactatos/farmacologia , Masculino , Fenóis/farmacologia
7.
J Pharm Biomed Anal ; 163: 45-57, 2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30286435

RESUMO

The diversity in phenols and polyphenols of stevia leaf has been simplified applying sequential fractionation techniques on its ethanol extract through ultrasound assisted maceration. Two of the fractions obtained by reverse-phase column chromatography resulted differently active in an extensive antioxidant and cytotoxic screening. Both fractions were chemically profiled by ultra-performance liquid chromatography (UHPLC) coupled with electrospray ionization (ESI) quadrupole/time-of-flight (QqTOF) mass spectrometry (MS). One of the fractions was composed mainly of chlorogenic acids and flavonol triglycosides, whereas the other was rich in flavonoids mono- and diglycosides and in their hydroxycinnamoyl derivatives. Among the fifty compounds identified, non-phenol metabolites, such as benzyl primeveroside and roseoside, as well as a lignan polyphenol (5'), are reported for the first time as constituents of the Stevia leaf.


Assuntos
Fracionamento Químico/métodos , Fenóis/análise , Extratos Vegetais/química , Stevia/química , Células 3T3 , Animais , Antineoplásicos/análise , Antineoplásicos/química , Antineoplásicos/farmacologia , Antioxidantes/análise , Antioxidantes/química , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Fracionamento Químico/instrumentação , Ácido Clorogênico/análise , Ácido Clorogênico/química , Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia Líquida de Alta Pressão/métodos , Ensaios de Seleção de Medicamentos Antitumorais/instrumentação , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Glicosídeos/análise , Glicosídeos/química , Humanos , Camundongos , Fenóis/química , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta/química , Ratos , Espectrometria de Massas por Ionização por Electrospray/instrumentação , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/instrumentação , Espectrometria de Massas em Tandem/métodos
8.
J Nat Prod ; 81(12): 2700-2709, 2018 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-30457871

RESUMO

A strain of the pathogenic fungus Ascochyta lentis isolated from lentil ( Lens culinaris) was studied to ascertain its capability to produce bioactive metabolites. From the culture filtrates were found three new anthraquinone derivatives, named lentiquinones A (1), B (2), and C (3), and the known lentisone. From the mycelium, four known analogues were identified, namely pachybasin (in larger amount), ω-hydroxypachybasin, 1,7-dihydroxy-3-methylanthracene-9,10-dione, and phomarin. Lentiquinones A-C were characterized by spectroscopic methods as 3,4,6-trihydroxy-8-methyl-2 H-benzo[ g]chromene-5,10-dione, 2,3,4,5,10-pentahydroxy-7-methyl-3,4,4a,10-tetrahydroanthracen-9(2 H)-one, and its 2-epimer, respectively, and the relative configuration of the two latter compounds was deduced by X-ray diffraction data analysis. The absolute configuration of lentiquinones B and C was determined as (2 R,3 S,4 S,4a S,10 R) and (2 S,3 S,4 S,4a S,10 R), respectively, by electronic circular dichroism (ECD) in solution and solid state, and TDDFT calculations. When tested by using different bioassays, the novel compounds showed interesting activities. In particular, applied to punctured leaves of host and nonhost plants, the three new compounds and lentisone caused severe necrosis, with lentiquinone A being the most active among the new metabolites. On cress ( Lepidium sativum), this latter compound proved to be particularly active in inhibiting root elongation. On Lemna minor all the compounds reduced the content of chlorophyll, with 1,7-dihyroxy-3-methylanthracene-9,10-dione being the most active. The new compounds, together with lentisone, proved to have antibiotic properties.


Assuntos
Antraquinonas/isolamento & purificação , Ascomicetos/química , Lens (Planta)/microbiologia , Micotoxinas/isolamento & purificação , Antraquinonas/química , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Germinação/efeitos dos fármacos , Estrutura Molecular , Micotoxinas/farmacologia , Plantas/efeitos dos fármacos
9.
Chirality ; 30(10): 1115-1134, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30153350

RESUMO

Plants and fungi are seemingly inexhaustible sources of interesting natural products with remarkable structural and biological diversity. One of the most important groups is the terpenes, ubiquitous natural products that are generated by 2 now well-established biosynthetic pathways: the older mevalonate and the more recently discovered 1-deoxyxylulose-5-phosphate. Among the diterpenes, the pimarane diterpenes are a very representative subgroup with several and interesting biological activities resulting from different functional group modifications. In this review, we outline the method of their structure determination, mainly spectroscopic results, their absolute configuration, and structure-activity relationships, were reported, as well as the mode of action for selected examples from plants, marine organisms, and fungi. The pimarane, isopimarane, and ent-pimarane diterpenes covered in this review have a wide range of biological activities including antimicrobial, antifungal, antiviral, phytotoxic, phytoalexin, cytotoxicity, and antispasmodic and relaxant effects.


Assuntos
Abietanos/química , Abietanos/farmacologia , Produtos Biológicos/química , Organismos Aquáticos/química , Plantas/química , Estereoisomerismo
10.
Molecules ; 23(4)2018 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-29621148

RESUMO

Fungi are able to produce many bioactive secondary metabolites that belong to different classes of natural compounds. Some of these compounds have been selected for their antagonism against pests and human pathogens and structure-activity relationship (SAR) studies have been performed to better understand which structural features are essential for the biological activity. In some cases, these studies allowed for the obtaining of hemisynthetic derivatives with increased selectivity and stability in respect to the natural products as well as reduced toxicity in view of their potential practical applications. This review deals with the SAR studies performed on fungal metabolites with potential fungicidal, bactericidal, insecticidal, and herbicidal activities from 1990 to the present (beginning of 2018).


Assuntos
Agentes de Controle Biológico/química , Agentes de Controle Biológico/farmacologia , Fungos/química , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Humanos , Estrutura Molecular , Plantas/parasitologia , Metabolismo Secundário , Relação Estrutura-Atividade
11.
J Agric Food Chem ; 66(13): 3435-3442, 2018 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-29537269

RESUMO

From the culture filtrates of Diaporthella cryptica, an emerging hazelnut pathogen, 2-hydroxy-3-phenylpropanoate methyl ester and its 3-(4-hydroxyphenyl) and 3-(1 H-indol-3-yl) analogues, named crypticins A-C, were isolated together with the well-known tyrosol. Crypticins A-C were identified by spectroscopic (essentially nuclear magnetic resonance and high-resolution electrospray ionization mass spectrometry) methods. The R absolute configuration (AC) of crypticin A was determined by comparing its optical rotation and electronic circular dichroism (ECD) spectrum with those of papuline, the methyl ester of (-)( S)-phenyllactic acid isolated as the main phytotoxin of Pseudomonas syringae pv.  papulans, responsible for apple blister spot. The ACs of crypticins B and C were determined by time-dependent density functional theory calculations of their ECD spectra. Papuline and the new metabolites herein isolated, except tyrosol, were tested at 1 mg/mL on cork oak, grapevine, hazelnut, and holm oak leaves using the leaf puncture assay. They were also tested on tomato cuttings at 0.5 and 0.05 mg/mL. In the leaf puncture assay, none of the compounds was found to be active. Crypticin C and papuline were active in the tomato cutting assay. Additionally, crypticin C displayed moderate inhibitory effect against Phytophthora cambivora.


Assuntos
Ascomicetos/química , Corylus/microbiologia , Micotoxinas/metabolismo , Doenças das Plantas/microbiologia , Ascomicetos/metabolismo , Dicroísmo Circular , Solanum lycopersicum/microbiologia , Estrutura Molecular , Micotoxinas/química , Quercus/microbiologia , Estereoisomerismo
12.
J Nat Prod ; 81(4): 1093-1097, 2018 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-29489357

RESUMO

Ascochyta lentis var. lathyri has recently been reported to be the causal agent of Ascochyta blight of grass pea ( Lathyrus sativus), a disease characterized by the appearance of necrotic lesions of leaves and stems. Considering the novelty of the pathogen and the possible involvement of secondary metabolites in symptom appearance, a study was carried out to ascertain the capability of this fungus to produce bioactive metabolites. Some phytotoxic phenols were isolated from the culture filtrates of the fungus. In particular, two new phytotoxic metabolites, named lathyroxins A and B, were characterized by spectroscopic methods as 4-(2-hydroxy-3,3-dimethoxypropyl)phenol and 3-(4-hydroxyphenyl)propane-1,2-diol, respectively, and the R absolute configuration of C-2 of their 2-dimethoxy- and 2,3-diol-propyl side chain was assigned. Moreover, other well-known fungal metabolites, namely, p-hydroxybenzaldehyde, p-methoxyphenol, and tyrosol, were also identified. Lathyroxins A and B showed interesting phytotoxic properties, being able to cause necrosis on leaves and to inhibit seed germination and rootlet elongation. Moreover, both of the new metabolites had no effect against bacteria, arthropods, and nematodes.


Assuntos
Ascomicetos/química , Lathyrus/microbiologia , Fenóis/química , Pisum sativum/microbiologia , Toxinas Biológicas/química , Benzaldeídos , Germinação/efeitos dos fármacos , Micotoxinas/química , Doenças das Plantas/microbiologia , Folhas de Planta/microbiologia , Raízes de Plantas/microbiologia
13.
J Exp Bot ; 69(12): 3095-3102, 2018 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-29590430

RESUMO

Jasmonates are signaling compounds that regulate plant responses to stress. Jasmonic acid (JA) is the direct precursor of the bioactive plant hormone JA-isoleucine (JA-Ile), the ligand of the CORONATINE INSENSITIVE 1-jasmonate ZIM-domain (COI1-JAZ) co-receptor complex. JA, its methyl ester, and three furanonyl esters were recently isolated from the grapevine pathogen Lasiodiplodia mediterranea. The JA ester lasiojasmonate A (LasA) is the first reported naturally occurring JA-furanone, and its mode of action has not yet been elucidated. Here, we show that LasA activates many JA-regulated responses in planta, including protein degradation, gene expression, and physiological processes. These in vivo effects require LasA conversion into JA, formation of JA-Ile, and its recognition by the plant JA-Ile perception complex. These findings suggest a mode of action of the natural fungal LasA as an inactive JA pool that can be transformed into the bioactive JA-Ile form. We propose that fungal production of JA derivates such as LasA occurs at late infection stages to induce plant JA responses such as cell death, and can facilitate fungal infection.


Assuntos
Arabidopsis/fisiologia , Ascomicetos/fisiologia , Ciclopentanos/metabolismo , Micotoxinas/metabolismo , Oxilipinas/metabolismo , Transdução de Sinais , Arabidopsis/microbiologia , Isoleucina/metabolismo
14.
Food Funct ; 9(3): 1840-1849, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29517778

RESUMO

The current cancer treatment scenario lacks drugs acting as both radiosensitizer and radioprotector agents. In this context, the radiomodulatory properties exerted by an aqueous extract from the fruits of the Italian Prunus avium cv. Della Recca (PaDRw) were investigated. The extract, obtained through an environmentally-friendly ultrasound-assisted extraction, seemed to act as a radioprotector at lower tested doses (25 and 50 µg mL-1) and a radiosensitizer at 400 and 500 µg mL-1 dose levels towards the neuroblastoma SH-SY5Y cell line, irradiated with four graded X-ray doses (0, 0.5, 2, and 4 Gy). The fractionation of PaDRw by Amberlite XAD-4 non-ionic polymeric resin, coupled to LC-UV-MS/MS techniques, proved to be efficient also in the disclosure of lower constituents. About 63% of the whole PaDRw extract was constituted of hexitol, followed by fructose (∼22.8%) and glucose (∼10.7%). Chlorogenic acids and flavonoids, which accounted only for ∼2.2%, were hypothesized to be the main actors in PaDRw-induced radiomodulation.


Assuntos
Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Prunus avium/química , Protetores contra Radiação/química , Protetores contra Radiação/isolamento & purificação , Protetores contra Radiação/farmacologia , Antioxidantes , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida , Frutas/química , Humanos , Itália , Extratos Vegetais/farmacologia , Espectrometria de Massas em Tandem , Ultrassom
15.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-686609

RESUMO

Infectious endometritis is one of the main causes of subfertility/infertility in the mare. In this report, we present the first case of endometritis in mare associated with a strain of Enterococcus casseliflavus, an unusual gram-positive bacterium which can also be a zoonotic agent. Furthermore, the isolated strain showed a worrying multidrug-resistant profile. The accurate finding of a successful antimicrobial treatment and consequently, the pregnancy diagnosis indicate the importance to isolate, identify and define the anti-biotic resistance profile of bacteria associated with endometritis.

16.
Mater Sci Eng C Mater Biol Appl ; 68: 205-212, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27524014

RESUMO

Sol-gel synthesis was exploited to entrap quercetin, a natural occurring antioxidant polyphenol, in silica-based hybrid materials, which differed in their polyethylene glycol (PEG) content (6, 12, 24 and 50wt%). The materials obtained, whose nano-composite nature was ascertained by Scanning Electron Microscopy (SEM), were chemically characterized by Fourier Transform InfraRed (FT-IR) and UV-Vis spectroscopies. The results prove that a reaction between the polymer and the drug occurred. Bioactivity tests showed their ability to induce hydroxyapatite nucleation on the sample surfaces. The direct contact method was applied to screen the cytotoxicity of the synthetized materials towards fibroblast NIH 3T3 cells, commonly used for in vitro biocompatibility studies, and three nervous system cell lines (neuroblastoma SH-SY5Y, glioma U251, and pheochromocytoma PC12 cell lines), adopted as models in oxidative stress related studies. Using the MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay NIH 3T3 proliferation was assessed and the morphology was not compromised by direct exposure to the materials. Analogously, PC-12, and U-251 cell lines were not affected by new materials. SH-SY5Y appeared to be the most sensitive cell line with cytotoxic effects of 20-35%.


Assuntos
Proliferação de Células/efeitos dos fármacos , Teste de Materiais , Polietilenoglicóis , Quercetina , Dióxido de Silício , Animais , Sobrevivência Celular/efeitos dos fármacos , Camundongos , Células NIH 3T3 , Células PC12 , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Quercetina/química , Quercetina/farmacologia , Ratos , Dióxido de Silício/química , Dióxido de Silício/farmacologia
17.
Food Chem Toxicol ; 95: 64-74, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27375189

RESUMO

In the course of a cytotoxicity screening of Mediterranean plants vs. neuroblastoma cells, Pistacia lentiscus was of interest. Pl-C extract, prepared from dried leaves by ultrasound assisted maceration (UAM) in chloroform, was profiled through using GC-MS techniques. To evaluate Pl-C cytotoxicity towards SH-SY5Y and SK-N-BE(2)-C cell lines, MTT, SRB and LDH assays were performed. The caspase-3 activation, DNA fragmentation, as well as micronucleation, were also evaluated. The Pl-C oxidant/antioxidant ability was estimated using different methods. The extract, rich in pentacyclic triterpenes, inhibited mitochondrial redox activity and cell viability of the tested cell lines. LDH assay established that Pl-C did not affect the cell membrane integrity. Indeed, it was able to activate caspase-3 and to cause a ladder pattern of DNA. Western blotting analysis showed that Pl-C processed caspase-3 providing two cleavage products of approximately 20 and 17-kDa, whose densitometric evaluation highlighted that Pl-C was more effective than vinblastine by 3-fold. The pro-apoptotic effect could be related to a disturbance in cell redox balance. In fact, it increased intracellular ROS production, GSSG/GSH ratio and the formation of lipoperoxidation products. The data obtained prompted to further investigate and assess the in vivo efficacy of Pl-C to prevent and/or treat neuroblastoma.


Assuntos
Apoptose/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Neuroblastoma/patologia , Neurônios/patologia , Pistacia/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Antioxidantes/metabolismo , Western Blotting , Caspase 3/metabolismo , Humanos , Metabolômica/métodos , Mitocôndrias/metabolismo , Neuroblastoma/tratamento farmacológico , Neuroblastoma/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Espécies Reativas de Oxigênio/metabolismo
18.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-672502

RESUMO

Objective: To update the recent knowledge of the microbiological causes of canine otitis externa in Campania Region (Italy) and the antibiotic susceptibility patterns of the iso-lated strains. Methods: A total of 122 dogs were examined by otoscopy, and auricular swab samples were collected from both ears in 74 dogs presenting clinical bilateral otitis and from single ears in 48 dogs displaying clinical unilateral otitis. Cytological examination, bacteriological analysis and antimicrobial susceptibility tests were performed. Results: Thirty-one out of 122 dogs were positive for yeast species (25.4%, 95% con-fidence interval (CI): 18.2%–34.2%) with a higher prevalence of Malassezia pachy-dermatis (21/31 isolates, 67.7%, CI: 48.5%–82.7%), and a total of 91 out of 122 dogs were positive for bacterial species (74.6%;CI:65.8%–81.8%) with a higher prevalence of Staphylococcus pseudintermedius (45/143 isolates, 31.5%, CI: 24.1%–39.8%). These results are the first description of Streptococcus agalactiae-associated otitis. The yeasts isolated showed high levels of susceptibility to all antifungal agents tested; on the con-trary all the isolated bacterial strains were highly resistant to at least four out of ten antimicrobial classes. Both Gram-positive and Gram-negative bacteria showed high resistance to amoxicillin/clavulanate and kanamycin hence they are not recommended as initial empirical therapy for the otitis treatment. Conclusions: This update illustrates an increase in antibiotic resistances providing an insight into the current knowledge of the therapeutic procedures followed on canine otitis externa in Italy. It also emphasizes the importance of considering the results of the microbiological and sensitivity tests to decide on an appropriate antibiotic therapy.

19.
Plant Foods Hum Nutr ; 70(3): 324-30, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26134879

RESUMO

In order to promote breeding programs and a full reintroduction into production of two local red-fleshed apple varieties grown in Bekran and Bastam (Iran), the evaluation of their antioxidant properties was of interest. LC-MS(n) based metabolic fingerprinting analyses were applied to investigate the anthocyanin content of both peel and flesh components of the fruits. Cyanidin-3-O-hexoside isomers were present in both 'Bekran' and 'Bastam' apples, whereas 'Bekran' apple was a valuable source of anthocyanin rutinose derivatives. Employing DPPH(•), ABTS(•+), and ORAC methods, the antiradical efficacy was evaluated. The ability of the investigated fruit components to scavenge OH(•), and O(2) (•-) reactive species was also assessed. ID(50) values highlighted the massive antioxidant response of 'Bekran' peel component, able to counteract by 50 % OH(•), and O(2) (•-) at 130.3 and 91.6 µg/mL, respectively. The cytoprotective screening towards HeLa, HepG2, A549, SH-5YSY, and SK-N-BE(2)-C cell lines evidenced that the investigated Iranian red-fleshed apple fruits were able to exert a significant antioxidant response in hydrogen peroxide oxidized cell systems. Data collected suggested that the revaluation of 'Bekran' and 'Bastam' apple cultivars could represent a precious source of antioxidant compounds whose dietary intake could improve the human well-being reducing risks of free radical related chronic and degenerative diseases.


Assuntos
Antocianinas/farmacologia , Antioxidantes/farmacologia , Frutas/química , Malus/química , Extratos Vegetais/farmacologia , Antocianinas/análise , Antioxidantes/análise , Benzotiazóis/metabolismo , Compostos de Bifenilo/metabolismo , Cromatografia Líquida de Alta Pressão , Dissacarídeos/análise , Dissacarídeos/farmacologia , Sequestradores de Radicais Livres/análise , Sequestradores de Radicais Livres/farmacologia , Células HeLa , Células Hep G2 , Humanos , Peróxido de Hidrogênio/farmacologia , Irã (Geográfico) , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Picratos/metabolismo , Extratos Vegetais/química , Especificidade da Espécie , Ácidos Sulfônicos/metabolismo
20.
Sci Technol Adv Mater ; 16(3): 035001, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27877802

RESUMO

The development of biomaterials with intrinsic antioxidant properties could represent a valuable strategy for preventing the onset of peri-implant diseases. In this context, quercetin, a naturally occurring flavonoid, has been entrapped at different weight percentages in a silica-based inorganic material by a sol-gel route. The establishment of hydrogen bond interactions between the flavonol and the solid matrix was ascertained by Fourier transform infrared spectroscopy. This technique also evidenced changes in the stretching frequencies of the quercetin dienonic moiety, suggesting that the formation of a secondary product occurs. Scanning electron microscopy was applied to detect the morphology of the synthesized materials. Their bioactivity was shown by the formation of a hydroxyapatite layer on sample surface soaked in a fluid that simulates the composition of human blood plasma. When the potential release of flavonol was determined by liquid chromatography coupled with ultraviolet and electrospray ionization tandem mass spectrometry techniques, the eluates displayed a retention time that was 0.5 min less than quercetin. Collision-activated dissociation mass spectrometry and untraviolet-visible spectroscopy were in accordance with the release of a quercetin derivative. The antiradical properties of the investigated systems were evaluated by DPPH and ABTS methods, whereas the 2,7-dichlorofluorescein diacetate assay highlighted their ability to inhibit the H2O2-induced intracellular production of reactive oxygen species in NIH-3T3 mouse fibroblast cells. Data obtained, along with data gathered from the MTT cytotoxicity test, revealed that the materials that entrapped the highest amount of quercetin showed notable antioxidant effectiveness.

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