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1.
Biol Sport ; 39(4): 1033-1042, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36247953

RESUMO

To investigate the effect of 20 min nap opportunity (N20), 5 mg · kg-1 of caffeine (CAF) and their combination (CAF+N20) on the biochemical response (energetic biomarkers, biomarkers of muscle damage and enzymatic antioxidants) to the running-based anaerobic sprint test. Fourteen highly trained male athletes completed in a double-blind, counterbalanced and randomized order four test sessions: no nap with placebo (PLA), N20, CAF and CAF+N20. Compared to PLA, all treatments enhanced maximum and mean powers. Minimum power was higher [(mean difference) 58.6 (95% confidence interval = 1.31-116) Watts] after CAF and [102 (29.9-175) Watts] after CAF+N20 compared to N20. Also, plasma glucose was higher after CAF [0.81 (0.18-1.45) mmol · l-1] and CAF+N20 [1.03 (0.39-1.64) mmol · l-1] compared to N20. However, plasma lactate was higher [1.64 (0.23-3.03) mmol · l-1] only after N20 compared to pre-exercise, suggesting a higher anaerobic glycolysis during N20 compared to PLA, CAF and CAF+N20. Caffeine ingestion increased post-exercise creatine kinase with [54.3 (16.7-91.1) IU · l-1] or without napping [58.9 (21.3-96.5) IU · l-1] compared to PLA. However, superoxide dismutase was higher after napping with [339 (123-554) U · gHB-1] or without caffeine [410 (195-625) U · gHB-1] compared to PLA. Probably because of the higher aerobic glycolysis contribution in energy synthesis, caffeine ingestion resulted in better repeated sprint performance during CAF and CAF+N20 sessions compared to N20 and PLA. Caffeine ingestion resulted in higher muscle damage, and the short nap enhanced antioxidant defence with or without caffeine ingestion.

2.
J Strength Cond Res ; 35(1): 132-140, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29864109

RESUMO

ABSTRACT: Romdhani, M, Hammouda, O, Smari, K, Chaabouni, Y, Mahdouani, K, Driss, T, and Souissi, N. Total sleep deprivation and recovery sleep affect the diurnal variation of agility performance: The gender differences. J Strength Cond Res 35(1): 132-140, 2021-This study aimed to investigate the effects of time-of-day, 24 and 36 hours of total sleep deprivation (TSD), and recovery sleep (RS) on repeated-agility performances. Twenty-two physical education students (11 male and 11 female students) completed 5 repeated modified agility T-test (RMAT) sessions (i.e., 2 after normal sleep night [NSN] [at 07:00 and 17:00 hours], 2 after TSD [at 07:00 hours, i.e., 24-hour TSD and at 17:00 hours, i.e., 36-hour TSD], and 1 after RS at 17:00 hours). The RMAT index decreased from the morning to the afternoon after NSN (p < 0.05, d = 1.05; p < 0.01, d = 0.73) and after TSD (p < 0.001, d = 0.92; d = 1.08), respectively, for total time (TT) and peak time (PT). This finding indicates a diurnal variation in repeated agility, which persisted after TSD. However, the diurnal increase in PT was less marked in the female group after NSN (2.98 vs. 6.24%). Moreover, TT and PT increased, respectively, after 24-hour TSD (p < 0.001; d = 0.84, d = 0.87) and 36-hour TSD (p < 0.001, d = 1.12; p < 0.01, d = 0.65). Female subjects' PT was less affected by 24-hour TSD (1.76 vs. 6.81%) compared with male subjects' PT. After 36-hour TSD, the amount of decrease was not different between groups, which increased the diurnal amplitude of PT only for male subjects. Total sleep deprivation suppressed the diurnal increase of PT and increased the diurnal amplitude of oral temperature only in women. Nevertheless, RS normalized the sleep-loss-induced performance disruption. Conclusively, sleep loss and RS differently affect repeated-agility performance of men and women during the day. Sleep extension postdeprivation could have potent restorative effect on repeated-agility performances, and female subjects could extract greater benefits.


Assuntos
Caracteres Sexuais , Privação do Sono , Ritmo Circadiano , Feminino , Humanos , Masculino , Fatores Sexuais , Sono
3.
Biol Sport ; 38(4): 629-638, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34937973

RESUMO

To compare the effects of two nap opportunities (20 and 90 min) to countermeasure the transient naturally occurring increased sleepiness and decreased performances during the post-lunch dip (PLD). Fourteen highly trained judokas completed in a counterbalanced and randomized order three test sessions (control (No-nap), 20- (N20) and 90-min (N90) nap opportunities). Test sessions consisted of the running-based anaerobic sprint test (RAST), simple and multiple-choice reaction times (MCRT) and the Epworth sleepiness scale (ESS). From the RAST, the maximum (Pmax), mean (Pmean) and minimum (Pmin) powers were calculated. Blood samples were taken before and after the RAST to measure the effect of pre-exercise napping on energetic and muscle damage biomarkers and antioxidant defense. N20 increased Pmax and Pmean compared to No-nap (p < 0.001, d = 0.59; d = 0.66) and N90 (p < 0.001, d = 0.98; d = 0.72), respectively. Besides, plasma lactate and creatinine increased only when the exercise was performed after N20. Both N20 (p < 0.001, d = 1.18) and N90 (p < 0.01, d = 0.78) enhanced post-exercise superoxide dismutase activity compared to No-nap. However, only N20 enhanced post-exercise glutathione peroxidase activity (p < 0.001, d = 1.01) compared to pre-nap. Further, MCRT performance was higher after N20 compared to No-nap and N90 (p < 0.001, d = 1.15; d = 0.81, respectively). Subjective sleepiness was lower after N20 compared to No-nap (p < 0.05, d = 0.92) and N90 (p < 0.01, d = 0.89). The opportunity to nap for 20 min in the PLD enhanced RAST, MCRT performances, and antioxidant defense, and decreased sleepiness. However, the opportunity of 90 min nap was associated with decreased repeated sprint performances and increased sleepiness, probably because of the sleep inertia.

4.
Biol Sport ; 36(1): 55-65, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30899140

RESUMO

To compare the effects of two types of partial sleep deprivation (PSD) at the beginning (PSDBN) and the end (PSDEN) of the night on mood, cognitive performances, biomarkers of muscle damage, haematological status and antioxidant responses before and after repeated-sprint exercise in the post-lunch dip. Fourteen male athletes performed the Running-based Anaerobic Sprint Test following: (i) baseline normal sleep night, (ii) PSDBN, or (iii) PSDEN in a randomized and counter-balanced order. During each condition, participants performed simple and choice reaction time tests, the Profile of Mood States, subjective sleepiness, and the Running-based Anaerobic Sprint Test. Plasma biomarkers of muscle damage, total blood count, and antioxidant activities were measured at rest and after the repeated sprint in the three conditions. PSDEN decreased Pmax (p=0.008; d=1.12), Pmean (p=0.002; d=1.33) and Pmin (p=0.006; d=1.15), whilst PSDBN decreased Pmean (p=0.04; d=0.68) and Pmin (p=0.028; d=0.58), in comparison with baseline. PSDEN exerted stronger effects on Pmax (p=0.013; d=0.74) and Pmean (p=0.048; d=0.54) than PSDBN. Moreover, PSDEN increased subjective sleepiness (p<0.001; d=1.93), while PSDBN impaired choice reaction time (p<0.001, d=1.89). Both PSD types decreased resting glutathione peroxidase (p<0.001; d=5.43, d=3.86), and increased aspartate amino-transferase levels (p<0.001; d=1.36, d=1.37) respectively for PSDEN and PSDBN. PSDEN decreased repeated-sprint performances more than PSDBN in the post-lunch dip. This could be explained by the lowered mood and resting antioxidant status and the increased inflammatory profile after PSDEN. Repeated-sprint exercise resulted in greater inflammation after PSDEN, despite the decreased physical performance. The drop of resting antioxidant defence and haemoglobin concentration after PSDEN could explain the increased sleep drive at the post-lunch dip.

5.
Microb Pathog ; 125: 448-453, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30316009

RESUMO

The overuse of antibiotics and biofilm formation ability has led to the emergence of bacterial resistant strains. The combined use of several antibiotics has been found as an efficient strategy to overcome this resistance. In this study, two exopolysaccharides (EPS) obtained from Lactobacillus plantarum (EPS-Lp) and Bacillus spp. (EPS-B), isolated from a traditional Tunisian food "ricotta cheese" and hypersaline environment respectively, were used to counteract the biofilm formation and efflux pumps activities in Escherichia coli ATCC35218. The obtained results revealed that the tested EPSs can be effective against E. coli at a concentration > 1 mg/ml and were able to modulate biofilm formation by 50%. Moreover, at a concentration of 512 µg/ml, the tested EPSs inhibit the EtBr efflux in the tested bacteria and no significant difference was shown compared to cells treated with reserpine (P > 0.05). The positive effect of the tested EPSs may be due to the decrease of Indole production level proposed as a signal involved in quorum sensing and through the significant reduction of the hydrophobicity percentage between the treated and untreated cells. Overall, EPS-Lp and EPS-B, when used at appropriate concentration, may inhibit biofilm formation and reduce efflux pumps implicated in bacterial adhesion and antimicrobial resistance. These results make them an interesting candidate in the design of a new strategies to control bacterial biofilm-associated infections.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Transporte Biológico Ativo/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Indóis/antagonistas & inibidores , Polissacarídeos Bacterianos/farmacologia , Antibacterianos/isolamento & purificação , Bacillus/isolamento & purificação , Bacillus/metabolismo , Microbiologia Ambiental , Escherichia coli/química , Escherichia coli/fisiologia , Microbiologia de Alimentos , Interações Hidrofóbicas e Hidrofílicas/efeitos dos fármacos , Lactobacillus plantarum/isolamento & purificação , Lactobacillus plantarum/metabolismo , Testes de Sensibilidade Microbiana , Polissacarídeos Bacterianos/isolamento & purificação , Percepção de Quorum/efeitos dos fármacos
6.
Microb Pathog ; 114: 153-162, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29146500

RESUMO

Disease outbreaks related to waterborne pathogen contamination throughout the world as well as challenges that lie ahead for addressing persistent infection are of renewed interest. In this research, we studied the effects of prolonged exposure of Salmonella enterica serovar Typhimurium to the cues encountered in the extracellular environment particularly in seawater microcosm on bacterial virulence and subsequent infection in Caco-2 cells. Our data show a significant difference in biofilm formation, swimming and swarming motilities between normal and stressed cells of S. Typhimurium under differing NaCl conditions (P < 0.05). Interestingly, adhesion, invasion and apoptotic activity to Caco-2 epithelial cells were determined during infection with normal and stressed Salmonella. Furthermore, we compared the expression of SPI-1 virulence genes (sopA, sopB, sopD, sopE2 and hilA) of normal and stressed S. Typhimurium in response to salt conditions encountered in the extracellular environment in LB broth and after epithelial cell exposure. The interest of the present study is due to the fact that to investigate the bacterial survival strategies during its movement from the natural surroundings to the host cell is fundamental to our understanding of the infection process during the host-pathogen interactions.


Assuntos
Proteínas de Bactérias/genética , Biofilmes , Infecções por Salmonella/microbiologia , Salmonella typhimurium/fisiologia , Fatores de Virulência/genética , Apoptose , Proteínas de Bactérias/metabolismo , Células CACO-2 , Regulação Bacteriana da Expressão Gênica , Interações Hospedeiro-Patógeno , Humanos , Salmonella typhimurium/citologia , Salmonella typhimurium/genética , Água do Mar/análise , Água do Mar/microbiologia , Cloreto de Sódio/análise , Cloreto de Sódio/metabolismo , Fatores de Virulência/metabolismo
7.
Microb Pathog ; 104: 56-63, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28062292

RESUMO

The Aims of the study was to evaluate the antibacterial susceptibility and the biofilm eradication of three natural compounds carvacrol (CAR), thymol (TH) and eugenol (EUG), alone or in combination with nalidixic acid (NA) against twelve Salmonella Typhimurium strains. The minimum inhibitory concentration (MIC) and the minimum biofilm eradication concentration (BEC50) of the tested compounds (CAR, TH and EUG) and their combinations with NA were evaluated. In order to assess whether these bacteria had active efflux pumps, ethidium bromide (EtBr) accumulation assays was achieved using spectrophotometric accumulation assays. Moreover, scanning electron microscopy was used to visualize the bacterial biofilm formation on stainless steel surfaces after exposed to NA, CAR, TH and EUG alone and in combination. TH was the most effective essential oil, with the lowest MICs values ranging from 32 to 128 µg/mL followed by EUG and CAR. In addition, the combination of NA with the different compounds enhances antibiotic susceptibility of the tested bacterial strains. These results were confirmed by EtBr accumulation assays. A pronounced effect in decreasing biofilm mass was also noticed. Moreover, SEM revealed that bacterial membrane was disrupted and a complete loss of membrane integrity was also evident. The combination of natural compounds with antibiotic enhances bacterial susceptibility to NA. This combination ameliorates eradication of biofilm formed by S. Typhimurium on polystyrene microtitre plates. Additionally, this synergy induces an alteration of the bacterial cell surface visualized by SEM.


Assuntos
Anti-Infecciosos/farmacologia , Biofilmes/efeitos dos fármacos , Farmacorresistência Bacteriana , Eugenol/farmacologia , Monoterpenos/farmacologia , Ácido Nalidíxico/farmacologia , Salmonella typhimurium/efeitos dos fármacos , Timol/farmacologia , Cimenos , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Testes de Sensibilidade Microbiana , Óleos Voláteis/farmacologia , Salmonella typhimurium/ultraestrutura
8.
Microb Pathog ; 106: 40-49, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27840222

RESUMO

Pathogenic bacteria such as Salmonella have the ability to respond to a wide variety of environmental stimuli. These responses allow them to survive and withstand insults both of an external location as well as within the host. The aim of this study was to investigate the effect of preadaptation in stressful conditions encountered in seawater microcosms for different periods of time on Salmonella Typhimurium survival, antibiotic susceptibility and interactions with Caco-2 cells. These results showed that the number of bacterial cells depends from the periods of stress in culture medium, highlighting the importance of using the right culture medium for the enumeration of stressed bacteria. The antibiotic resistance of starved cells was modified and their exposure to stressful conditions in seawater during 12 months significantly increased adhesion, invasion and cytotoxic activities on Caco-2 cells. Moreover, cellular cytokines IL-6 and IL-8 secretions were up-regulated. Present results seem to suggest that the preadaptation of S. Typhimurium in seawater microcosms affect the cultural characters by the appearance of the atypical cells that may play a critical role in the intestinal infection and in the systemic spread of the disease. These findings are very important to understand bacterial responses to changing conditions and explain the persistence of these atypical in eukaryotic cells.


Assuntos
Aderência Bacteriana/efeitos dos fármacos , Citocinas/metabolismo , Citocinas/farmacologia , Infecções por Salmonella/imunologia , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/imunologia , Células CACO-2/citologia , Células CACO-2/efeitos dos fármacos , Meios de Cultura , Farmacorresistência Bacteriana , Meio Ambiente , Interações Hospedeiro-Patógeno/imunologia , Humanos , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Transmissão , Modelos Biológicos , Salmonella typhimurium/crescimento & desenvolvimento , Salmonella typhimurium/patogenicidade , Água do Mar/microbiologia , Estresse Fisiológico , Fatores de Tempo
9.
Microb Pathog ; 109: 214-220, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28583888

RESUMO

Because of their functional diversity, bioactive compounds are becoming a new biocontrol agent to limit biofilm formation by pathogens. In this study, the physico-chemical characterization of an exopolysaccharide (EPS) isolated from Lactobacillus plantarum (EPLB) was characterized and its in vitro effect on biofilm formation was studied. The EPS had a molecular weight of 36 kDa and polydispersity index estimated to be 1.2. The tested EPLB had an antibacterial activity, with a Minimal Inhibition Concentration (MIC) values ranging between 1 mg/ml and 10 mg/ml, displayed an antibiofilm effect concentration dependent on Gram positive and negative strains. Among the pathogenic strains, 2 out of 4 appeared to be more than 50% inhibited in their biofilm development by the EPS. The antibiofilm activity can be due to the ability of the EPS to influence the function of biological membranes like hydrophobicity that decreased (P < 0.05) when the EPS was used at a concentration of 512 µg/ml. This EPS without cytotoxic effect, showed an antioxidant effect on the quenching of DPPH radicals and the inhibition of lipid peroxidation with a percentage of 64% and 66%, respectively. Taken together these biological properties, EPLB can be considered as a potential prebiotic agent in the design of new therapeutic strategies for bacterial biofilm-associated infections.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Bactérias/efeitos dos fármacos , Polissacarídeos Bacterianos/farmacologia , Prebióticos , Probióticos/química , Animais , Artemia/efeitos dos fármacos , Ácido Ascórbico/metabolismo , Biofilmes/crescimento & desenvolvimento , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sequestradores de Radicais Livres , Ácido Gálico/metabolismo , Humanos , Interações Hidrofóbicas e Hidrofílicas , Lactobacillus plantarum/química , Ácido Linoleico/metabolismo , Testes de Sensibilidade Microbiana , Polissacarídeos Bacterianos/química , Testes de Toxicidade
10.
Microb Pathog ; 112: 156-163, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28964825

RESUMO

Dental caries remains the most prevalent oral infectious disease worldwide. In this study, the antibacterial and the antibiofilm activities of five essential oils (EO's): eugenol (EUG), carvacrol (CAR), thymol (TYH), p-cymene (CYM) and γ-terpinene (TER) were tested (alone or in combinaison with tetracycline) against oral bacteria. In addition, their potential roles to enhance the accumulation of ethidium bromide (EtBr) in bacterial cells were tested. Our results indicated that EO's induced a selective antimicrobial activity. A synergistic effect of EO's and tetracycline (TET) was noticed with a reduction rate ranged from 2 to 8-fold. In addition, the efflux of EtBr was inhibited with a decrease in loss of EtBr from the bacteria. On the other hand a significant anti-biofilm activities of EO's (alone or combined with antibiotics) was noticed. In conclusion the tested EO's may be considered as a potential natural source with a resistance-modifying activity and may be applied to eradicate bacterial biofilm.


Assuntos
Bactérias/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Farmacorresistência Bacteriana/efeitos dos fármacos , Eugenol/farmacologia , Monoterpenos/farmacologia , Boca/microbiologia , Timol/farmacologia , Antibacterianos , Monoterpenos Cicloexânicos , Cimenos , Cárie Dentária/microbiologia , Esmalte Dentário/microbiologia , Sinergismo Farmacológico , Etídio/farmacologia , Testes de Sensibilidade Microbiana , Microbiota/efeitos dos fármacos , Microscopia Eletrônica de Varredura , Óleos Voláteis/farmacologia , Staphylococcus aureus/citologia , Staphylococcus aureus/efeitos dos fármacos , Tetraciclina/farmacologia
11.
Microb Pathog ; 99: 95-100, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27521228

RESUMO

In this study thymol (THY) and carvacrol (CAR), two monoterpenic phenol produced by various aromatic plants, was tested for their antibacterial and efflux pump inhibitors potencies against a panel of clinical and foodborne pathogenes. Our results demonstrated a substantial susceptibility of the tested bacteria toward THY and CAR. Especially, THY displayed a strong inhibitory activity (MIC's values ranged from 32 to 64 µg/mL) against the majority of the tested strains compared to CAR. Moreover, a significant reduction in MIC's of TET and benzalkonium chloride (QAC) were noticed when tested in combinations with THY and CAR. Their synergic effect was more significant in the case of THY which resulted a reduction of MIC's values of TET (2-8 fold) and QAC (2-8 fold). We noted also that THY and CAR inhibited the ethidium bromide (EtBr) cell efflux in a concentration-dependent manner. The rate of EtBr accumulation in food-borne pathogen was enhanced with THY and CAR (0, 250 and 500 µg/mL). The lowest concentration causing 50% of EtBr efflux inhibition (IC 50) was noticed in Salmonella enteritidis (1129) at 150 µg/mL of THY and 190 µg/mL of CAR respectively. These findings indicate that THY and CAR may serve as potential sources of efflux pump inhibitor in food-borne pathogens.


Assuntos
Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Transporte Biológico Ativo/efeitos dos fármacos , Doenças Transmitidas por Alimentos/microbiologia , Monoterpenos/farmacologia , Compostos Fitoquímicos/farmacologia , Timol/farmacologia , Anti-Infecciosos/isolamento & purificação , Bactérias/isolamento & purificação , Bactérias/metabolismo , Compostos de Benzalcônio/farmacologia , Cimenos , Sinergismo Farmacológico , Etídio/metabolismo , Concentração Inibidora 50 , Testes de Sensibilidade Microbiana , Monoterpenos/isolamento & purificação , Compostos Fitoquímicos/isolamento & purificação , Tetraciclina/farmacologia , Timol/isolamento & purificação
12.
Microb Pathog ; 101: 44-49, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27816681

RESUMO

In this study the minimal inhibitory concentration (MICs) of tetracycline (Tet), erythromycin (Ery) and benzalkonium chloride (BC) in absence and in presence of a sub-MIC of juglone (Jug) were determined. In addition, the Ethidium bromide (EtBr) efflux assay was performed to assess the effect of Jug on EtBr cells accumulation. Our results showed a selective antimicrobial activity of Jug against the tested strains. A synergistic effect of Jug, drugs (Tet and Ery) and disinfectant (BC) was noticed with a reduction rate varied from 2 to 16-fold. In addition, the efflux of EtBr was inhibited depending on the Jug concentration. In the presence of Jug, a decrease in loss of EtBr from bacteria was observed. The concentration inducing 50 % of EtBr efflux inhibition after 15 min was about 182 µg ml-1 for S. aureus ATCC 25923, 236 µg ml-1 for S. aureus B193 and 195 µg ml-1 for S. aureus B456. It appears from this study that Jug may be used as a natural source for resistance-modifying activity in same bacteria.


Assuntos
Antibacterianos/farmacologia , Transporte Biológico Ativo/efeitos dos fármacos , Desinfetantes/farmacologia , Inibidores Enzimáticos/farmacologia , Boca/microbiologia , Naftoquinonas/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Compostos de Benzalcônio/farmacologia , Criança , Sinergismo Farmacológico , Eritromicina/farmacologia , Etídio/metabolismo , Humanos , Testes de Sensibilidade Microbiana , Staphylococcus aureus/isolamento & purificação , Staphylococcus aureus/metabolismo , Tetraciclina/farmacologia , Tunísia
13.
Microb Pathog ; 97: 213-20, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27317856

RESUMO

In this study, three lactic acid bacteria (LAB), isolated from barley, traditional dried meat and fermented olive were characterized and tested for their anti-bacterial and anti-biofilm activities against oral bacteria. Our results revealed that the tested LAB were γ-hemolytic and were susceptible to four antibiotics. All the strains were resistant to low pH, bile salt, pepsin and pancreatin. Furthermore, FB2 displayed a high aut-oaggregative phenotype (99.54%) while FF2 exhibited the best co-aggregation rate. Concerning the microbial adhesion to solvent, FB2 was the most hydrophobic strain (data obtained with chloroform and n-hexadecane). In addition Pediococcus pentosaceus FB2 and Lactobacillus brevis FF2 displayed a significant inhibitory effect against Streptococcus salivarius B468 (MIC = 10%). Moreover the selected strains were able to inhibit biofilm formation of Bacillus cereus ATCC14579 (MBIC50 = 28.16%) and S. salivarius B468 (MBIC50 = 42.28%). The selected LAB could be considered as candidate probiotics for further application in functional food and mainly in the prevention of oral diseases.


Assuntos
Antibiose , Bacillus cereus/crescimento & desenvolvimento , Biofilmes/crescimento & desenvolvimento , Lactobacillales/fisiologia , Boca/microbiologia , Probióticos , Streptococcus salivarius/crescimento & desenvolvimento , Bacillus cereus/fisiologia , Microbiologia de Alimentos , Hordeum/microbiologia , Lactobacillales/crescimento & desenvolvimento , Lactobacillales/isolamento & purificação , Testes de Sensibilidade Microbiana , Streptococcus salivarius/fisiologia
14.
Biol Res ; 49: 22, 2016 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-27067415

RESUMO

BACKGROUND: Disturbance of the equilibrium between reactive oxygen species (ROS) and anti-oxidants (AOX) has been implicated in various diseases, including atherosclerosis, the most common pathologic process underlying coronary heart disease (CHD). Thus, the defense systems against ROS are critical protecting blood vessel walls against oxidative damage. In this study, we investigate whether Ala16Val MnSOD and Pro198Leu GPx polymorphisms are associated with CHD susceptibility and/or severity. METHODS: Both polymorphisms were genotyped in a sample of 203 controls and 164 patients. CHD risk and severity, antioxidant status (enzymatic and/or non enzymatic) and biochemical parameters were assessed and analysed by genotype. RESULTS: A significant association of MnSOD variant to CHD risk was revealed in males. Males harboring the Val/Val genotype were approximately at twofold increased risk of CHD compared to controls (Ala carriers vs Val/Val, adjusted OR 1.89; 95 % CI 1.18‒3.42, p = 0.03). Significant decreases in SOD activity and total antioxidant status (TAS) were observed in Val carriers and by CHD status. Whereas, no association of GPx variant genotype (Leu/Leu) and activity to cardiopathy events was discerned. CHD severity, as demonstrated by the number of vessel stenosis, was associated with significantly higher frequency of Val allele and LDL levels in CHD subjects. CONCLUSIONS: Our results showed a lack of association of Pro198Leu GPx polymorphism to CHD risk and severity. However, they suggest that Ala16Val MnSOD polymorphism and decreased antioxidant defences are likely contributed to CHD risk in Tunisian men. Furthermore, the Val encoding MnSOD allele and decreased SOD activity were significantly correlated with CHD stenosis progression.


Assuntos
Doença das Coronárias/genética , Glutationa Peroxidase/genética , Polimorfismo Genético , Superóxido Dismutase/genética , Adulto , Idoso , Análise de Variância , Estudos de Casos e Controles , Doença das Coronárias/patologia , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo , Reação em Cadeia da Polimerase , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Tunísia , Glutationa Peroxidase GPX1
15.
J Stroke Cerebrovasc Dis ; 25(11): 2585-2593, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27474112

RESUMO

BACKGROUND: Ischemic stroke (IS) usually initiates inflammation and oxidative stress leading to neuronal death. Diabetes and impaired fasting glucose are associated with incidence of cerebrovascular and cardiovascular diseases. METHODS: In the present study, we assessed the relationship of fasting glucose with antioxidative parameters (erythrocyte glutathione peroxidase [GPx] and superoxide dismutase [SOD] activities) and inflammatory markers (high-sensitivity C-reactive protein [hs-CRP] and fibrinogen) in IS patients with and without type 2 diabetes mellitus (T2DM). In addition, we determined factors associated with the risk of IS among these patients. Antioxidative, inflammatory, and lipid parameters were measured in 196 patients with IS (117diabetics and 79 nondiabetics). RESULTS: After adjustment of covariates, multiple logistic regression analysis showed that SOD and GPx significantly decreased the risk of IS among patients with and without T2DM. However, hs-CRP increased the risk of IS. For the diabetic patients, fasting glucose was positively correlated with hs-CRP and fibrinogen and was negatively correlated with GPx and SOD levels. In addition, fasting glucose and hemoglobin A1c or glycosylated hemoglobin (HbA1c) have been shown to increase the risk of IS in diabetic patients. CONCLUSIONS: These data suggest that the antioxidant activity of plasma may be an important factor that provides protection from IS. hs-CRP concentrations can be used as a clinical screening tool to identify individuals with higher risk of IS. Finally, fasting glucose and HbA1c may also be useful indicators for cerebrovascular risk in diabetic patients that may be mediated by low levels of antioxidative defense markers and high inflammation status.


Assuntos
Isquemia Encefálica/sangue , Proteína C-Reativa/análise , Eritrócitos/enzimologia , Fibrinogênio/análise , Glutationa Peroxidase/sangue , Mediadores da Inflamação/sangue , Estresse Oxidativo , Acidente Vascular Cerebral/sangue , Superóxido Dismutase/sangue , Idoso , Biomarcadores/sangue , Glicemia/análise , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/enzimologia , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/diagnóstico , Feminino , Hemoglobinas Glicadas/análise , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Acidente Vascular Cerebral/diagnóstico
16.
Microb Pathog ; 71-72: 32-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24814824

RESUMO

The occurrence of several microbial species in the oral cavity of 4-12-year-old Tunisian children was investigated. Samples were taken from 158 children (81 caries actives and 77 caries free). Genomic DNA was extracted and analyzed for the presence of 17 microbial species using a polymerase chain reaction assay. All samples were positive for at least one of the target microbial strains. Streptococcus mutans was the most prevalent species (76.5%) detected in genomic DNA collected from carious lesions. Other prevalent species were Candida spp (63%), Streptococcus salivarius (59%) and Streptococcus oralis (42%). The frequency of Lactobacillus acidophilus, Lactobacillus plantarum, and Lactobacillus casei-group in caries lesions was 29.5%, 34.5% and 22% respectively. Pathogenic bacteria such as Staphylococcus aureus was found in 28.5% of carious lesion samples compared to 15.5% in the control. Frequency of Porphyromonas endodontali, Actinomyces radicidentis and Treponema denticola recovery did not differ significantly between origins of samples. PCR analysis of genomic DNA detect various oral bacteria that differ between caries actives and caries-free children. In addition, the association of same aciduric bacteria (S. mutans, S. salivarius, L. acidophilus) and caries formation was noticed.


Assuntos
Bactérias/classificação , Bactérias/genética , Biodiversidade , DNA Bacteriano/isolamento & purificação , Cárie Dentária/microbiologia , Candida/genética , Criança , Pré-Escolar , DNA Bacteriano/genética , DNA Fúngico/genética , DNA Fúngico/isolamento & purificação , Feminino , Humanos , Masculino , Reação em Cadeia da Polimerase
17.
BMC Microbiol ; 11: 155, 2011 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-21714920

RESUMO

BACKGROUND: Enterococci are increasingly associated with opportunistic infections in Humans but the role of the oral cavity as a reservoir for this species is unclear. This study aimed to explore the carriage rate of Enterococci in the oral cavity of Tunisian children and their antimicrobial susceptibility to a broad range of antibiotics together with their adherence ability to abiotic and biotic surfaces. RESULTS: In this study, 17 E. faecalis (27.5%) and 4 E. faecium (6.5%) were detected. The identified strains showed resistance to commonly used antibiotics. Among the 17 isolated E. faecalis, 12 strains (71%) were slime producers and 5 strains were non-producers. Among the 4 E. faecium, 2 strains were slime producers. All the tested strains were able to adhere to at least one of the two tested cell lines. Our result showed that 11 E. faecalis and 2 E. faecium strains adhered strongly to Hep-2 as well as to A549 cells. CONCLUSIONS: Drugs resistance and strong biofilm production abilities together with a high phenotypic adhesion to host cells are important equipment in E. faecalis and E. faecium which lead to their oral cavity colonization and focal infections.


Assuntos
Aderência Bacteriana , Portador Sadio/epidemiologia , Cárie Dentária/microbiologia , Farmacorresistência Bacteriana , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/fisiologia , Enterococcus faecium/efeitos dos fármacos , Enterococcus faecium/fisiologia , Infecções por Bactérias Gram-Positivas/epidemiologia , Antibacterianos/farmacologia , Biofilmes/crescimento & desenvolvimento , Portador Sadio/microbiologia , Linhagem Celular , Criança , Pré-Escolar , Enterococcus faecalis/isolamento & purificação , Enterococcus faecium/isolamento & purificação , Células Epiteliais/microbiologia , Infecções por Bactérias Gram-Positivas/complicações , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Polissacarídeos Bacterianos/metabolismo , Tunísia/epidemiologia
18.
Microb Pathog ; 50(1): 1-5, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21093575

RESUMO

To analyze the degree of biofilm formation on three ica-positives Staphylococcus epidermidis as a function of biocides, the medium was supplemented with increasing concentrations of isopropanol, ethanol, and methanol at 0, 1, 4, 6, 8, 10, 12 and 14% (v/v), hydrogen peroxide (0, 0.125, 0.25, 0.5, 1, 2, 3, 4 and 5% v/v) and benzalkonium chloride (0, 0.125, 0.25, 0.5, 1, 2, 3, 4 and 6 µg ml⁻¹). In biocide-free biofilms, the results showed that two strains (S. epidermidis CIP106510 and E24) were strongly biofilm positive displaying a high oxidative activity (1.254 and 0.855, respectively) in comparison with the non-adherent one (S22). In addition biofilm formation was induced with 1% alcohol (isopropanol and ethanol) supplementation. The three studied strains cultured in TSB supplemented with 2% methanol displayed a strong oxidative activity (P=0.008). Moreover wells with 0.125% hydrogen peroxide enhanced increasing oxidative activity of S. epidermidis CIP106510 and S22. A significant induction of biofilm was noted after treatment with 1 µg ml⁻¹ of benzalkonium chloride. This study suggests that some biocides currently used in hospitals are ineffective against nosocomial pathogens growing in biofilms when used at weak concentration and fail to control this reservoir for hospital-acquired infection.


Assuntos
Álcoois/farmacologia , Compostos de Benzalcônio/farmacologia , Biofilmes/efeitos dos fármacos , Desinfetantes/farmacologia , Peróxido de Hidrogênio/farmacologia , Staphylococcus epidermidis/efeitos dos fármacos , Anilidas/química , Biofilmes/crescimento & desenvolvimento , Colorimetria , Staphylococcus epidermidis/crescimento & desenvolvimento , Sais de Tetrazólio/química
19.
Ann Clin Microbiol Antimicrob ; 10: 29, 2011 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-21707998

RESUMO

BACKGROUND: The presence of resistant bacteria in the oral cavity can be the major cause of dental antibiotic prophylaxis failure. Multidrug efflux has been described for many organisms, including bacteria and fungi as part of their drugs resistance strategy. The discovery of a new efflux pump inhibitor could extend the useful lifetime of some antibiotics. METHODS: In this study, the MICs of thymoquinone (TQ), tetracycline and benzalkonium chloride (BC) were determined in absence and in presence of a sub-MIC doses of thymoquinone (1/2 MIC). In addition the 4,6-diamidino-2-phenylindole (DAPI) efflux assay was carried out to determine the effect of TQ on DAPI cells accumulation. RESULTS: TQ induced a selective antimicrobial activity. Its synergic effect resulted in at least a 4-fold potentiation of the tested antibiotics and antiseptic. In addition, TQ inhibited the DAPI efflux activity in a concentration-dependent manner. The rate of DAPI accumulation in clinical isolates was enhanced with TQ (0 to 200 µg/ml). There is also a decrease in loss of DAPI from bacteria in the presence of TQ. The concentration causing 50% of DAPI efflux inhibition after 15 minutes was approximately 59 µg/ml for Pseudomonas aeroginosa and 100 µg/ml and Staphylococcus aureus respectively. CONCLUSIONS: TQ possesses a selective antibacterial activity against oral bacteria. It is therefore suggested that TQ could be used as a source of natural products with resistance-modifying activity. Further investigation is needed to assess their clinical relevance.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Benzoquinonas/farmacologia , Farmacorresistência Bacteriana , Doenças da Boca/microbiologia , Infecções Bacterianas/microbiologia , Humanos , Testes de Sensibilidade Microbiana , Boca/microbiologia
20.
BMC Complement Altern Med ; 11: 29, 2011 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-21489272

RESUMO

BACKGROUND: Thymoquinone is an active principle of Nigella sativa seed known as "Habbah Al-Sauda" in Arabic countries and "Sinouj" in Tunisia. Bacterial biofilms tend to exhibit significant tolerance to antimicrobials drugs during infections. METHODS: The antibacterial activity of Thymoquinone (TQ) and its biofilm inhibition potencies were investigated on 11 human pathogenic bacteria. The growth and development of the biofilm were assessed using the crystal violet (CV) and the 2, 3-bis [2-methyloxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxanilide (XTT) reduction assay. RESULTS: TQ exhibited a significant bactericidal activity against the majority of the tested bacteria (MICs values ranged from 8 to 32 µg/ml) especially Gram positive cocci (Staphylococcus aureus ATCC 25923 and Staphylococcus epidermidis CIP 106510). Crystal violet assay demonstrated that the minimum biofilm inhibition concentration (BIC50) was reached with 22 and 60 µg/ml for Staphylococcus aureus ATCC 25923 and Staphylococcus epidermidis CIP 106510 respectively. In addition our data revealed that cells oxidative activity was influenced by TQ supplementation. In the same way, TQ prevented cell adhesion to glass slides surface. CONCLUSION: The ability of TQ to prevent biofilm formation warrants further investigation to explore its use as bioactive substances with antibiofilm potential.


Assuntos
Antibacterianos/farmacologia , Benzoquinonas/farmacologia , Biofilmes/efeitos dos fármacos , Nigella sativa/química , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/fisiologia , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/fisiologia , Humanos , Testes de Sensibilidade Microbiana , Sementes/química
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