Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Artigo em Inglês | MEDLINE | ID: mdl-38957977

RESUMO

Background: Post-partum infection is a major contributor to maternal mortality and is responsible for approximately 10% of maternal fatalities worldwide. The risk of infection is substantially higher in cesarean section procedures. Approximately 8% of women who undergo cesarean sections are susceptible to infection. Although the body of evidence supporting the regular pre-operative utilization of prophylactic antibiotic treatment is steadily expanding, its usefulness in cesarean sections has not yet been standardized, and post-partum infection is still a serious medical challenge. We aimed to retrospectively assess the prophylactic effectiveness of cefazolin in combination with other antibiotic agents in cesarean sections. Materials and Methods: Both uni-variable and multi-variable analyses were conducted to identify factors that may affect cefazolin pre-operative antibiotic prophylaxis in elective cesarean section operations. The uni-variable analysis included timing of administration, operation duration, body mass index (BMI), and wound type. A multi-variable logistic regression model was then created to determine which variables provide independent information in the context of other variables. Results: Time of administration did not affect prophylactic cefazolin efficacy. However, prophylactic cefazolin was 1.43 and 1.77 times more effective when the operation lasted for 45 minutes or more, compared with operations that were shorter than 45 minutes. Patients with a BMI ranging from 18 to 29 kg/m2 showed increased efficacy of prophylactic cefazolin compared with obese patients with a BMI exceeding 30 kg/m2. The effectiveness of prophylactic cefazolin decreased by 95% in patients with clean-contaminated surgical incisions compared with those with clean surgical incisions. Conclusions: Our findings demonstrate that administering pre-operative prophylactic antibiotic agents to women undergoing cesarean section resulted in a reduction in post-partum infections, thereby reducing maternal mortality. Furthermore, optimal timing of administration, re-dosing if necessary, length of prophylactic medication, and dosing adjustments for obese patients are crucial factors in preventing surgical site infections and promoting antimicrobial stewardship.

2.
Front Pharmacol ; 15: 1406653, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38835668

RESUMO

Background: P. aeruginosa, a significant bacterium, can cause severe illness and resistance to antibiotics. Quorum sensing (QS) systems regulate virulence factors production. Targeting QS could reduce bacteria pathogenicity and prevent antibiotic resistance. Cruciferous vegetables contain sulforaphane, known for its anti-inflammatory, antioxidant, anticancer, and antimicrobial properties. Aim: We aimed to examine the inhibitory influences of sulforaphane, at a sub-inhibitory concentration (» minimum inhibitory concentration, MIC), on virulence and QS in P. aeruginosa. Materials and methods: The sulforaphane's anti-virulence actions at sub-inhibitory concentrations were explored in vitro and in vivo. A sub-MIC concentration of sulforaphane was combined with anti-pseudomonal drugs, and the results of this combination were assessed. The virtual affinity of sulforaphane for the receptors of QS was studied, and its effect on the expression of QS genes was quantified. Results: Sulforaphane significantly decreased the biofilm formation, motility, ability to withstand oxidative stress, and the synthesis of virulence extracellular enzymes such as proteases, hemolysins, and elastase, as well as other virulence factors like pyocyanin. In addition, sulforaphane lessened the severity of P. aeruginosa infection in mice. Sulforaphane reduced the antipseudomonal antibiotics' MICs when used together, resulting in synergistic effects. The observed anti-virulence impacts were attributed to the ability of sulforaphane to inhibit QS via suppressing the QS genes' expression. Conclusion: Sulforaphane shows promise as a potent anti-virulence and anti-QS agent that can be used alongside conventional antimicrobials to manage severe infections effectively. Furthermore, this study paves the way for further investigation of sulforaphane and similar structures as pharmacophores for anti-QS candidates.

3.
ACS Omega ; 9(24): 26724-26734, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38911808

RESUMO

The cactus family plant has been used in folk medicine for a long time. In this work, Opuntia stricta chemical composition and its antioxidative and anti-inflammatory properties were investigated. Our results showed that O. stricta is highly rich in fibers and minerals. The present study assessed the levels of polyphenol contents and antioxidant and in vivo anti-inflammatory activities. The highest phenolic compounds and antioxidant activity were observed in the methanolic extract. Concerning the qualitative analysis, nine phenolic and organic acids were identified and quantified by high-performance liquid chromatography (HPLC). Luteolin-7-Glu (4.25 µg/g), apigenin-7-Glu (3.15 µg/g), and catechin (2.85 µg/g) were identified as major phenolic compounds. The predominant fatty acids detected by gas chromatography (GC) coupled to a flame ionization detector were linoleic and linolenic acids (35.11%). A factorial design plan was used to determine the effect of temperature, agitation speed, and maceration period on phenolic contents. In vivo, the methanol extract from Opuntia stricta showed anti-inflammatory activity. The computational modeling reveals that O. stricta compounds bind VEGF, IL-6, and TNF-α with high binding scores that reach -8.7 kcal/mol and establish significant molecular interactions with some key residues that satisfactorily explain both in vitro and in vivo findings. These data indicate that Opuntia stricta cladode powder could be potentially useful in pharmaceutical and food applications.

4.
Saudi J Biol Sci ; 30(8): 103718, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37576067

RESUMO

Inevitably, high concentrations of iron, the most widely produced ore globally, can be found in aquatic environments. To assess the toxicity of iron on aquatic organisms, Ruditapes decussatus specimens were subjected to microparticles derived from two types of iron ore (hematite and magnetite) at four different concentrations (0.5, 1, 1.5, and 5 g/L). The findings revealed that both types of iron ore were absorbed by clams in a concentration-dependent manner. Biomarkers analysis demonstrated significant and organ-specific impacts on the health of the clams caused by these microparticles, which was further supported by computational analyses on bioavailability. Within seven days of exposure, changes were observed in the activities of several enzymes, including catalase, acetylcholinesterase, and glutathione S-transferases, as well as in the rate of lipid peroxidation in both the digestive gland and gills. This study provides an environmental perspective on the toxicological effects of iron ore microparticles.

5.
Molecules ; 28(13)2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37446686

RESUMO

In this study, we investigated in vitro the potential of Trichoderma harzianum to produce bioactive secondary metabolites that can be used as alternatives to synthetic compounds. The study focused on analyzing two extracts of T. harzianum using ethyl acetate and n-butanol solvents with different polarities. The extracts were examined using phytochemical analysis to determine the content of polyphenols, flavonoids, tannins, and alkaloids. Thin-layer chromatography (TLC) and Gas chromatography-mass spectroscopy (GC-MS) analysis were used to profile volatile organic metabolites (VOCs) present in the extracts. Furthermore, the extracts were tested for their antifungal ability using the poison food technique. For measuring antioxidant activity, the 1,1-diphenyl-2-picryl-hydrazyl (DPPH) test was used. Trichoderma harzianum was shown to have a significantly high content of tannins and alkaloids, with a noticeable difference between the two extracts. GC-MS analysis identified 33 potential compounds with numerous benefits that could be used in agriculture and the medicinal industry. Moreover, strong antifungal activity was identified against Sclerotinia sclerotiorum by 94.44%, Alternaria sp. by 77.04%, and Fusarium solani by 51.48; similarly, the IC50 of antioxidant activity was estimated for ethyl acetate extract by 71.47% and n-butanol extract by 56.01%. This leads to the conclusion that Trichoderma harzianum VOCs play a significant role as an antifungal and antioxidant agent when taking into account the advantageous bioactive chemicals noted in the extracts. However, to our knowledge, this is the first study in Algeria presenting detailed phytochemical analysis and GC-MS profiling of Trichoderma harzianum for two extracts, ethyl acetate and n-butanol.


Assuntos
Antifúngicos , Trichoderma , Antifúngicos/química , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , 1-Butanol , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/metabolismo , Taninos/metabolismo , Extratos Vegetais/química , Trichoderma/metabolismo
6.
Molecules ; 28(5)2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36903521

RESUMO

Centaurea parviflora (C. parviflora), belonging to the family Asteraceae, is an Algerian medicinal plant used in folk medicine to treat different diseases related to hyperglycemic and inflammatory disorders, as well as in food. The present study aimed to assess the total phenolic content, in vitro antioxidant and antimicrobial activity and phytochemical profile of the extracts of C. parviflora. The extraction of phenolic compounds from aerial parts was conducted using solvents of increasing polarity starting from methanol, resulting in crude extract (CE), to chloroform extract (CHE), ethyl acetate extract (EAE) and butanol extract (BUE). The total phenolic, flavonoid and flavonol contents of the extracts were determined using the Folin-Ciocalteu and AlCl3 methods, respectively. The antioxidant activity was measured with seven methods: 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, galvinoxyl free-radical-scavenging test, 2,2'-Azino-Bis(3-Ethylbenzothiazoline-6-Sulfonic Acid) (ABTS) assay, cupric reducing antioxidant capacity (CUPRAC), reducing power, Fe+2-phenanthroline reduction assay and superoxide-scavenging test. The disc-diffusion method aimed at testing the sensitivity of bacterial strains toward our extracts. A qualitative analysis with thin-layer chromatography of the methanolic extract was performed. Moreover, HPLC-DAD-MS was used to establish the phytochemical profile of the BUE. The BUE was found to contain high amounts of total phenolics (175.27 ± 2.79 µg GAE/mg E), flavonoids (59.89 ± 0.91 µg QE/mg E) and flavonols (47.30 ± 0.51 µg RE/mg E). Using TLC, different components such as flavonoids and polyphenols were noted. The highest radical-scavenging ability was recorded for the BUE against DPPH (IC50 = 59.38 ± 0.72 µg/mL), galvinoxyl (IC50 = 36.25 ± 0.42 µg/mL), ABTS (IC50 = 49.52 ± 1.54 µg/mL) and superoxide (IC50 = 13.61 ± 0.38 µg/mL). The BUE had the best reducing power according to the CUPRAC (A0.5 = 71.80 ± 1.22 µg/mL), phenanthroline test (A0.5 = 20.29 ± 1.16 µg/mL) and FRAP (A0.5 = 119.17 ± 0.29 µg/mL). The LC-MS analysis of BUE allowed us to identify eight compounds including six phenolic acids and two flavonoids: quinic acid, five chlorogenic acid derivatives, rutin and quercetin 3-o-glucoside. This preliminary investigation revealed that the extracts of C. parviflora have a good biopharmaceutical activity. The BUE possesses an interesting potential for pharmaceutical/nutraceutical applications.


Assuntos
Anti-Infecciosos , Centaurea , Antioxidantes/química , Cromatografia Líquida , Fenantrolinas , Superóxidos , Espectrometria de Massas em Tandem , Extratos Vegetais/química , Flavonoides/análise , Fenóis/análise , Compostos Fitoquímicos/química
7.
Environ Pollut ; 286: 117300, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33971469

RESUMO

An experimental study was carried out to determine the effects of the enrichment of sediments by endocrine perturbators on free-living nematodes from the Ghar El Melh lagoon, Tunisia. For 30 days, four concentrations of Estradiol Benzoate (hereafter EB) (0.43, 4.3, 8.6 and 12.9 ng l-1). The average nematode abundances showed a significant increase after the introduction of EB in their close environment. In contrast, the taxonomic examination has shown a decrease in species diversity of nematodes. The ordination of treatments according to the nMDS showed a clear structural separation of the enriched replicates with EB from controls based on species lists, in particular for concentrations EB3 and EB4. Indeed, under such conditions, the nematofauna exhibited a more remarkable presence of a new record for Science Theristus n. sp. and a decrease in relative abundances of Paracomesoma dubium. On feeding level, a predominance of non-selective deposit-feeders and a decline in proportions of epistrate feeders and carnivorous omnivores was observed with increasing concentrations of EB. Furthermore, in treated replicates with EB, females discernibly showed an increase compared to controls. Overall, EB affect significantly features of meiobenthic nematodes starting from the concentration of 4.3 ng l-1.


Assuntos
Nematoides , Animais , Estradiol/análogos & derivados , Tunísia
8.
Environ Sci Pollut Res Int ; 28(27): 36523-36534, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33694119

RESUMO

The toxicity of copper, cadmium, and dieldrin in adult Gammarus locusta (a marine amphipod) is currently unclear. Thus, G. locusta from the North Lake of Tunis were subjected to acute toxicity tests to assess LC50s at 48-96 h and to biomarker response tests through the assessment of catalase and acetylcholinesterase activities and malondialdehyde levels. The present study demonstrated the abilities of a chlorinated hydrocarbon pesticide (dieldrin) induce to oxidative stress and neurotoxicity. The comparison of metal toxicity showed that G. locusta was more sensitive to cadmium than copper. The three stressors caused significant inductions of all three biomarkers in a concentration-dependent manner. Catalase induction was dependent on exposure duration for all pollutants, while only copper led to increased malondialdehyde with longer exposure times. Catalase induction and malondialdehyde increase appeared to be sex dependent for all three pollutants. The neurotoxic effects of the pollutants were concentration dependent according to inhibition of acetylcholinesterase activity. In conclusion, catalase, malondialdehyde, and acetylcholinesterase are efficient biomarkers of copper, cadmium, and dieldrin in G. locusta.


Assuntos
Anfípodes , Inseticidas , Poluentes Químicos da Água , Animais , Biomarcadores , Cádmio/toxicidade , Cobre/toxicidade , Dieldrin/toxicidade , Inseticidas/toxicidade , Poluentes Químicos da Água/toxicidade
9.
Environ Pollut ; 277: 116727, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33640809

RESUMO

The response taxonomic and trophic of meiobenthic organisms, especially marine nematodes to polybrominated diphenyl ether (BDE-47) was studied using a community from Bizerte lagoon (Nord-East Tunisia). Four concentrations of BDE-47 [D1 (2.5 µg/kg dw), D2 (25 µg/kg dw), D3 (50 µg/kg dw), and D4 (100 µg/kg dw)] were applied, and responses were determined 30 days after exposure. Species abundance and all univariate indices were significantly affected in all treated microcosms compared to the control. The non-parametric cluster based on species abundance separated the nematode population into two groups: control + all treated microcosms. After grouping nematode species according to their trophic diversity, their abundance showed differential responses. The non-metric multi-dimensional scaling analysis and cumulative k-dominance based on the abundance of trophic groups abundances reflected significant separation between the control microcosm and each treatment condition. The correspondence analysis 2D plot generated from nematode species and trophic groups abundance showed the control microcosm was dominated by microvores, represented by two species of Terschellingia. However, when treated with the highest concentration of BDE-47, the community was occupied by the resistant trophic groups of facultative predators and epigrowth feeders represented by Metoncholaimus pristiurus and Paracomesoma dubium, respectively.


Assuntos
Éteres Difenil Halogenados , Nematoides , Animais , Éteres Difenil Halogenados/toxicidade , Tunísia
10.
Sci Total Environ ; 770: 145251, 2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-33508666

RESUMO

Trophic web structuring in aquatic sediments is dependent on the biological interactions between metazoans and microbial communities. The presence of pollutants in these biotas can therefore impact the meiofauna structure via the modification of the microbial communities. The current study examined in a laboratory bioassay the response of meiobenthic communities, particularly marine nematode taxa from the Bizerte Lagoon to the effect of the most detected polybrominated diphenyl ether in this aquatic environment, BDE-47. Four doses [D1 (2.5 ppb Dry weight (DW)), D2 (25 ppb DW), D3 (50 ppb DW), and D4 (100 ppb DW)] were gradually applied and sediment microcosms were incubated for 30 days in the presence or absence of meiofauna. Our results show that BDE-47-enriched sediments decreased the meiofaunal taxa and bacterial abundance. A lower taxonomic diversity of the nematodes' general structure was observed with all doses used. The numerical analysis of the two dimensional (2D) non-metric multidimensional scaling (nMDS) plots and the evolution of the relative abundances of each functional group of nematode genus assemblages revealed that the abundance of all biological traits was modified. Nevertheless, only three of the functional traits, adult length, feeding group, and amphid shape, showed a clear difference between the control and the treated microcosms. The similarity percentage analysis (SIMPER) revealed that the average dissimilarity between nematode genera communities and biological traits increased with BDE-47-enriched sediments. The nMDS second-stage ordination of inter-matrix rank correlations for matrices including genera and biological traits showed that the amphid shape was the functional trait closest to the generic distribution. Finally, the Principal Component Analysis (PCA) for the nematode biological traits and bacteria indicated a positive correlation of these microbes with the functional groups [1A, Cr, and ef], and a negative correlation only with the "cla"-type tail shape.


Assuntos
Nematoides , Poluentes Químicos da Água , Animais , Bactérias , Sedimentos Geológicos , Éteres Difenil Halogenados/análise , Poluentes Químicos da Água/análise
11.
Environ Pollut ; 266(Pt 1): 115263, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32768926

RESUMO

A microcosm experiment was carried out to study the ecotoxicity and interactions between heavy metals and polyvinyl chloride microplastics. Fifteen treatments were tested and results were examined after one month. In details, this work aims to study the ecotoxicological effects of cadmium (10 and 20 mg kg-1 Dry Weight DW), polyvinyl chloride (PVC) and its modified forms; PVC-DETA (PD) and PVC-TETA (PT) (20 and 40 mg kg-1 DW), separately and in mixtures, on meiofauna from Bizerte lagoon (NE Tunisia) with focus on nematode features. The results obtained showed that individual treatments were toxic for meiofauna and particularly for free-living nematodes. No clear trends characterized the numerical responses but significant reductions were observed for diversity indices. Moreover, the binary combinations of contaminants have a lesser toxic effect compared to their individual effects. This effect could be related to the high-capacity chelating ability of PVC and its polymers against cadmium.


Assuntos
Cádmio , Cloreto de Polivinila , Animais , Microplásticos , Plásticos , Tunísia
12.
Environ Sci Process Impacts ; 17(5): 997-1004, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25948118

RESUMO

Dispersant application is used as a response technique to minimize the environmental risk of an oil spill. In nearshore areas, dispersant application is a controversial countermeasure: environmental benefits are counteracted by the toxicity of dispersant use. The effects of the use of chemical dispersants on meiobenthic organisms and nematodes were investigated in a mesocosm experiment. A 20 day experiment was performed in four experimental sets of mesocosms. In three of them, sediments were contaminated, respectively by oil (500 mg kg(-1)), dispersed oil (oil + 5% dispersant), and dispersant alone, whereas in the last set sediments were kept undisturbed and used as a reference (Re). Our results showed that the meiobenthic response to oil contamination was rapid, for copepods and nematodes. One-way ANOVA showed a significant decrease of the abundance of copepods. In the case of nematodes, univariate and multivariate analyses indicated a clear decrease of the abundance of the species after only 20 days of pollutant exposure and thus reducing Shannon-Wiener diversity and Pielou's evenness. In contrast, Sphaerolaimus gracilis and Sabateria sp. became more frequent within disturbed assemblages and appeared to be resistant and/or opportunistic species in the presence of these kinds of toxicants. Moreover, responses of copepods and nematodes to the treatment seemed to be the same irrespective of whether only oil or oil + dispersant was performed. The main toxicities of dispersed oil come not from the "composition of a newly formed oil and oil spill dispersant mixture" but from the "quantities of increased dispersed oil droplets".


Assuntos
Poluição por Petróleo , Petróleo/toxicidade , Tensoativos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Organismos Aquáticos , Copépodes , Ecossistema , Monitoramento Ambiental , Recuperação e Remediação Ambiental , Invertebrados , Petróleo/análise , Medição de Risco , Tensoativos/análise , Poluentes Químicos da Água/análise
13.
Environ Sci Pollut Res Int ; 20(6): 3760-70, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23179214

RESUMO

The objective of this study was to test the hypotheses that (1) free-living marine nematodes respond in a differential way to diesel fuel if it is combined with three trace metals (chromium, copper, and nickel) used as smoke suppressants and that (2) the magnitude of toxicity of diesel fuel differs according to the level of trace metal mixture added. Nematodes from Sidi Salem beach (Tunisia) were subjected separately for 30 days to three doses of diesel fuel and three others of a trace metals mixture. Simultaneously, low-dose diesel was combined with three amounts of a trace metal mixture. Results from univariate and multivariate methods of data evaluation generally support our initial hypothesis that nematode assemblages exhibit various characteristic changes when exposed to different types of disturbances; the low dose of diesel fuel, discernibly non-toxic alone, became toxic when trace metals were added. For all types of treatments, biological disturbance caused severe specific changes in assemblage structure. For diesel fuel-treated microcosms, Marylynnia bellula and Chromaspirinia pontica were the best positive indicative species; their remarkable presence in given ecosystem may predict unsafe seafood. The powerful toxicity of the combination between diesel fuel and trace metals was expressed with only negative bioindicators, namely Trichotheristus mirabilis, Pomponema multipapillatum, Ditlevsenella murmanica, Desmodora longiseta, and Bathylaimus capacosus. Assemblages with high abundances of these species should be an index of healthy seafood. When nematodes were exposed to only trace metals, their response looks special with a distinction of a different list of indicative species; the high presence of seven species (T. mirabilis, P. multipapillatum, Leptonemella aphanothecae, D. murmanica, Viscosia cobbi, Gammanema conicauda, and Viscosia glabra) could indicate a good quality of seafood and that of another species (Oncholaimellus mediterraneus) appeared an index of the opposite situation.


Assuntos
Cromo/toxicidade , Cobre/toxicidade , Gasolina/toxicidade , Nematoides/efeitos dos fármacos , Níquel/toxicidade , Poluentes da Água/toxicidade , Animais , Organismos Aquáticos/efeitos dos fármacos , Bioensaio , Relação Dose-Resposta a Droga , Ecossistema , Monitoramento Ambiental , Sedimentos Geológicos/química , Análise Multivariada , Água do Mar/química , Tunísia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA