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1.
Appl Psychophysiol Biofeedback ; 46(2): 183-194, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33877492

RESUMO

Neurofeedback (NF) training based on alpha upregulation has been widely used on patient and healthy populations. However, active voluntary modulation of central or widespread posterior alpha in response to central alpha feedback is still ambiguous. The objective of this study is to confirm whether patients learn to truly increase alpha power and to determine if patients modulate central or widespread alpha power when alpha feedback is provided from central brain region. This EEG-based NF study was conducted on seven paraplegic patients with same injury type, pain location, and sensitization to ensure homogeneity. In addition to routine NF training sessions, various experiments were performed to compare alpha NF modulation received from C4 with alpha shift during cognitive tasks, occipital or parieto-occipital cortex, and Laplacian montage which is expected to separate localized alpha from widespread alpha, to attain objectives. Moreover, imaginary coherence analysis in alpha band was also performed to check whether C4 training site is coupled with other brain regions and to confirm whether activity at training site leads/lags the activity of other brain regions. The results indicate widespread alpha modulation in patients during regular NF sessions (p < 0.05) with large effect size (> 0.8), sufficiently high statistical power (> 80%), and a narrower confidence interval (CI) in response to NF provided from the central brain region reflecting less uncertainty and higher precision. However, small effect size obtained with Laplacian montage require patients to be trained with Laplacian feedback to achieve a reliable conclusion regarding localized alpha modulation. The outcomes of this study are not only limited to validate true alpha modulation in response to central alpha feedback but also to explore the mechanism of central alpha NF training.


Assuntos
Eletroencefalografia , Neurorretroalimentação , Encéfalo , Humanos , Aprendizagem , Regulação para Cima
2.
Phys Chem Chem Phys ; 22(4): 2414-2423, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31939468

RESUMO

The effects of solvents and temperature on the crystal formation were investigated for vinylidene fluoride/trifluoroethylene copolymer P(VDF-TrFE). Highly crystalline P(VDF-TrFE) thin films were fabricated by spin-casting using various polar solvents such as diethyl carbonate (DEC), methyl ethyl ketone (MEK), N,N-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO). Ferroelectric polarisation reversal of the P(VDF-TrFE) was evidenced by a displacement (D)-electric field (E) hysteresis loop measurement and supported by the presence of pyroelectric activity. The samples which were annealed above 100 °C gave elongated rod-like crystalline structures and the highest crystallinity, Xc of 83% was formed at 120 °C. Consequently, remnant polarisation (85 mC m-2) and the pyroelectric coefficient (30 µC m-2 K-1) were enhanced. Thus, annealing plays a substantial role in controlling the crystalline structure of P(VDF-TrFE) films regardless of the choice of solvent. Although, the crystalline structure control is almost independent of the solvent's polarity, the choice of solvent is essential in preparing a smoother film surface. Molecular dynamics of P(VDF-TrFE) are discussed from the observation of two dielectric relaxation processes, ß and γ related to the segmental micro-Brownian and local modes, respectively. The complete ferroelectric polarization reversal caused a reduction in the dielectric polarization and reduced the lattice spacing of the 110/200 planes.

3.
Radiat Environ Biophys ; 59(3): 483-501, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32333105

RESUMO

For the first time, Rhizophora spp. (Rh. spp.) particleboard phantoms were developed using defatted soy flour (DSF) and soy protein isolate (SPI) modified by sodium hydroxide and itaconic acid polyamidoamine-epichlorohydrin (IA-PAE) adhesive. The microstructural characterization and X-ray diffraction patterns of the material revealed that the modified DSF and SPI adhesives became more compact and homogeneous when NaOH/IA-PAE was added, which prevented damage by moisture. It was confirmed that the composite is crystalline with (101), (002), and (004) orientations. Phantoms made of this material were scanned with X-ray computed tomography (CT) typically used for abdominal examinations with varying energies corresponding to 80, 120, and 135 kVp, to determine CT numbers, electron densities, and density distribution profiles. The radiation attenuation parameters were found to be not significantly different from those of water (XCOM) with p values [Formula: see text] 0.05 for DSF and SPI. The DSF- and SPI-based particleboard phantoms showed CT numbers close to those of water at the three X-ray CT energies. In addition, electron density and density distribution profiles of DSF-SPI-Rh. spp. particleboard phantoms with 15 wt% IA-PAE content were even closer to those of water and other commercial phantom materials at the three X-ray CT energies. It is concluded that DSF-SPI with NaOH/IA-PAE added can be used as a potential adhesive in Rh. spp. particleboard phantoms for radiation dosimetry.


Assuntos
Farinha , Imagens de Fantasmas , Proteínas de Soja , Tomografia Computadorizada por Raios X , Madeira , Radioterapia , Rhizophoraceae , Glycine max
4.
Phys Chem Chem Phys ; 18(22): 15182-90, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-27199168

RESUMO

The molecular dynamics of a synthetic branched chain glycolipid, 2-decyl-tetradecyl-ß-d-maltoside (C14-10G2), in the dry assemblage of smectic and columnar liquid crystal phases has been studied by dielectric spectroscopy as a function of frequency and temperature during the cooling process. Strong relaxation modes were observed corresponding to the tilted smectic and columnar phases, respectively. At low frequency (∼900 Hz to 1 kHz) in the smectic phase, Process I* was observed due to the tilted sugar bilayer structure. The process continued in the columnar phase (Process I) with an abrupt dynamic change due to phase transition in the frequency range of ∼1.3 kHz to 22 kHz. An additional process (Process II) was observed in the columnar phase with a broader relaxation in the frequency range of ∼10 Hz to 1 kHz. A bias field dependence study was performed in the columnar phase and we found that the relaxation strength rapidly decreased with increased applied dc bias field. This relaxation originates from a collective motion of polar groups within the columns. The results of dielectric spectroscopy were supported by a molecular dynamics simulation study to identify the origin of the relaxation processes, which could be related to the chirality and hydrogen bonds of the sugar lipid.


Assuntos
Glicolipídeos/química , Maltose/análogos & derivados , Simulação de Dinâmica Molecular , Espectroscopia Dielétrica , Ligação de Hidrogênio , Cristais Líquidos/química , Maltose/química , Transição de Fase , Temperatura
5.
Artigo em Inglês | MEDLINE | ID: mdl-29620802

RESUMO

Vibrio alginolyticus is a halophilic gram-negative marine pathogen. The modes of transmission are mainly via direct contact with seawater and indirect contact through marine creatures. We report here a 28-year-old accountant diagnosed with right leg abscess after being bitten and scratched by a stray cat. Vibrio alginolyticus was isolated from the pus sample. The patient gave no history of contact with ocean water immediately before or after the cat scratch episode. The patient did apply commercial sea cucumber oil to the wound; we presume this is the cause of the Vibrio alginolyticus wound infection. To the best of our knowledge, this is the first reported case of Vibrio alginolyticus wound infection caused by commercially available sea cucumber oil.


Assuntos
Mordeduras e Picadas/complicações , Pepinos-do-Mar/microbiologia , Vibrioses/microbiologia , Vibrio alginolyticus/isolamento & purificação , Adulto , Animais , Gatos , Feminino , Humanos
6.
J Chem Phys ; 141(8): 085101, 2014 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-25173043

RESUMO

Glycolipid, found commonly in membranes, is also a liquid crystal material which can self-assemble without the presence of a solvent. Here, the dielectric and conductivity properties of three synthetic glycolipid thin films in different thermotropic liquid crystal phases were investigated over a frequency and temperature range of (10(-2)-10(6) Hz) and (303-463 K), respectively. The observed relaxation processes distinguish between the different phases (smectic A, columnar/hexagonal, and bicontinuous cubic Q) and the glycolipid molecular structures. Large dielectric responses were observed in the columnar and bicontinuous cubic phases of the longer branched alkyl chain glycolipids. Glycolipids with the shortest branched alkyl chain experience the most restricted self-assembly dynamic process over the broad temperature range studied compared to the longer ones. A high frequency dielectric absorption (Process I) was observed in all samples. This is related to the dynamics of the hydrogen bond network from the sugar group. An additional low-frequency mechanism (Process II) with a large dielectric strength was observed due to the internal dynamics of the self-assembly organization. Phase sensitive domain heterogeneity in the bicontinuous cubic phase was related to the diffusion of charge carriers. The microscopic features of charge hopping were modelled using the random walk scheme, and two charge carrier hopping lengths were estimated for two glycolipid systems. For Process I, the hopping length is comparable to the hydrogen bond and is related to the dynamics of the hydrogen bond network. Additionally, that for Process II is comparable to the bilayer spacing, hence confirming that this low-frequency mechanism is associated with the internal dynamics within the phase.


Assuntos
Glicolipídeos/química , Cristais Líquidos/química , Transição de Fase , Espectroscopia Dielétrica , Ligação de Hidrogênio , Simulação de Dinâmica Molecular , Espalhamento a Baixo Ângulo , Difração de Raios X
7.
Genet Mol Res ; 13(1): 920-5, 2014 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-24634112

RESUMO

Bats are important flagship species for biodiversity research; however, diversity in Southeast Asia is considerably underestimated in the current checklists and field guides. Incorporation of DNA barcoding into surveys has revealed numerous species-level taxa overlooked by conventional methods. Inclusion of these taxa in inventories provides a more informative record of diversity, but is problematic as these species lack formal description. We investigated how frequently documented, but undescribed, bat taxa are encountered in Peninsular Malaysia. We discuss whether a barcode library provides a means of recognizing and recording these taxa across biodiversity inventories. Tissue was sampled from bats trapped at Pasir Raja, Dungun Terengganu, Peninsular Malaysia. The DNA was extracted and the COI barcode region amplified and sequenced. We identified 9 species-level taxa within our samples, based on analysis of the DNA barcodes. Six specimens matched to four previously documented taxa considered candidate species but currently lacking formal taxonomic status. This study confirms the high diversity of bats within Peninsular Malaysia (9 species in 13 samples) and demonstrates how DNA barcoding allows for inventory and documentation of known taxa lacking formal taxonomic status.


Assuntos
Biodiversidade , Quirópteros/classificação , Quirópteros/genética , Código de Barras de DNA Taxonômico , Animais , Evolução Molecular , Malásia , Filogenia
8.
Zootaxa ; 3765: 54-68, 2014 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-24870884

RESUMO

Two new black fly species, Simulium (Gomphostilbia) brinchangense and S. (G.) tanahrataense, are described on the basis of reared adult females, males, pupae and larvae from Cameron's Highlands, Peninsular Malaysia. These new species are assigned to the asakoae species-group within Simulium (Gomphostilbia) and taxonomic notes are given to distinguish each new species from six known species in Malaysia. Revised keys to identify all 21 species including 13 species from other countries are provided for females, males, pupae and mature larvae. The species diversity of the asakoae species-group in Cameron's Highlands is briefly noted.


Assuntos
Dípteros/anatomia & histologia , Dípteros/classificação , Animais , Demografia , Dípteros/fisiologia , Feminino , Larva/anatomia & histologia , Larva/classificação , Larva/fisiologia , Malásia , Masculino , Pupa/anatomia & histologia , Pupa/classificação , Pupa/fisiologia , Especificidade da Espécie
9.
Artigo em Inglês | MEDLINE | ID: mdl-38698225

RESUMO

PURPOSE: To determine the variation of OXIS contact areas in primary molars using digital impressions generated from an intraoral scanner (IOS). METHODS: A cross-sectional study was carried out on 214 caries-free posterior quadrants of 80 children (38 males and 42 females) aged 3-6 years. Calibration of taking digital impressions with the IOS procedure was performed initially through scanning of ten quadrants of children to provide a learning environment to the examiner. The digital impressions were then exported, and the type of interproximal contact areas present between the distal surface of the primary first molar and the mesial surface of the primary second molar were identified according to the OXIS classification. The prevalence of the types of OXIS contact areas was expressed in the form of numbers and percentages. The chi-square test was applied to investigate the variability among the arches and to understand the association of OXIS contact areas across age, gender, and arches. RESULTS: The most common contact area type observed was I-type (59.8%), followed by S-type (15.4%), X-type (12.6%), and O-type (12.2%). The I-type contact area was most frequently seen in both males (51.6%) and females (65.5%), while the S-type contact area in males (14.7%) and X-type contact area in females (8.4% each) were the least frequent with no statistical significance between genders (p > 0.05). All three age groups studied showed the highest prevalence of the I-type contact area, which increased with an increase in age (p < 0.05). The inter-arch comparison showed a significant result in terms of the X-type contact area on the right side, and O-type, X-type, and I-type contact areas on the left side, while no statistical difference was seen in the intra-arch comparison for all contact types. CONCLUSION: I-type contact areas were the most prevalent across the arches, age groups and genders.

10.
Bioresour Bioprocess ; 11(1): 60, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38884830

RESUMO

Nanoparticles (NPs) formulation in biopolymers is an attractive process for the researcher to decrease the disadvantages of NPs application alone. Bimetallic NPs are a promising formula of two NPs that usually act as synergetic phenomena. Zinc oxide and gold NPs (ZnO@AuNPs) biosynthesis as a bimetallic was prepared via the eco-friendly manner currently. Carboxymethylcellulose (CMC) was employed for the formulation of ZnO@AuNPs as a nanocomposite via a green method. Physicochemical and topographical characterization was assigned to ZnO@AuNPs and nanocomposite features. The nanostructure of bimetallic NPs and nanocomposite were affirmed with sizes around 15 and 25 nm, respectively. Indeed, the DLS measurements affirmed the more reasonable size and stability of the prepared samples as 27 and 93 nm for bimetallic NPs and nanocomposite, respectively. The inhibitory potential of nanocomposite was more than ZnO@AuNPs against Staphylococcus aureus, Escherichia coli, Salmonella typhi, Enterococcus faecalis, Mucor albicans, Aspergillus flavus, and Mucor circinelloid. ZnO@AuNPs and nanocomposite exhibited antioxidant activity via DPPH with IC50 of 71.38 and 32.4 µg/mL, correspondingly. Excellent anti-diabetic potential of nanocomposite with IC50 of 7.4 µg/mL, and ZnO@AuNPs with IC50 of 9.7 µg/mL was reported compared with the standard acarbose with the IC50 of 50.93 µg/mL for amylase inhibition (%). Photocatalytic degradation of RR195 and RB dyes was performed by ZnO@AuNPs and nanocomposite, where maximum degradation was 85.7 ± 1.53 and 88.7 ± 0.58%, respectively using ZnO@AuNPs, 90.3 ± 0.28 and 91.8 ± 0.27%, respectively using nanocomposite at 100 min.

11.
J Appl Microbiol ; 114(2): 384-95, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23176757

RESUMO

AIMS: Halophilic micro-organisms have received much interest because of their potential biotechnological applications, among which is the capability of some strains to synthesize polyhydroxyalkanoates (PHA). Halomonas sp. SK5, which was isolated from hypersaline microbial mats, accumulated intracellular granules of poly(3-hydroxybutyrate) [P(3HB)] in modified accumulation medium supplemented with 10% (w/v) salinity and 3% (w/v) glucose. METHODS AND RESULTS: A cell density of approximately 3.0 g l(-1) was attained in this culture which yielded 48 wt% P(3HB). The bacterial strain was also capable of synthesizing poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)] when cofed with relevant precursors. Feeding with sodium valerate (0.7 mol l(-1) carbon) at various time intervals within 36 h resulted in 3HV molar fractions ranging from 6 up to 54 mol%. Oil palm trunk sap (OPTS) and seawater as the carbon source and culture medium respectively facilitated a significant accumulation of P(3HB). Simplified downstream processing based on osmotic lysis in the presence of alkali/detergent for both dry and wet biomass resulted in approximately 90-100% recovery of polymers with purity as high as 90%. Weight-average molecular weight (M(w) ) of the polymers recovered was in the range of 1-2 × 10(6) . CONCLUSIONS: Halomonas sp. SK5 was able to synthesize P(3HB) homopolymer as well as P(3HB-co-3HV) copolymer from various carbon sources. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first time a comprehensive study of both production and downstream processing is reported for Halomonas spp.


Assuntos
Halomonas/metabolismo , Poli-Hidroxialcanoatos/biossíntese , Biomassa , Meios de Cultura , Halomonas/crescimento & desenvolvimento , Halomonas/isolamento & purificação , Peso Molecular , Poliésteres/metabolismo , Poli-Hidroxialcanoatos/química , Poli-Hidroxialcanoatos/isolamento & purificação , Salinidade , Água do Mar
12.
BMC Public Health ; 13: 1010, 2013 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-24160571

RESUMO

BACKGROUND: This study was conducted to examine the prevalence of smoking and the smoking habits among male secondary school students in Jeddah, Kingdom of Saudi Arabia and to assess their knowledge and attitudes towards smoking. METHODS: A cross-sectional study was conducted in Jeddah, using a two-stage cluster sample that randomly selected four schools from 85 public secondary schools for males. Data were obtained through a self-administered questionnaire containing questions on personal background, smoking behavior, knowledge, and behavior and attitudes towards smoking. A total of 695 students responded to the questionnaires with an 87.4% response rate. RESULTS: The age range of this student sample was 16-22 years. Two hundred fifty-eight (37%) of the study group were current smokers. The most common reasons given for smoking were personal choice (50.8%) and the peer pressure from smoker friends (32.8%). Many students researched the smoking hazards (68.1%), but only 47.6% knew about the bad effects of passive smoking. Two thirds of the smoking students wanted to quit smoking (63.2%), especially if suitable help was available, and 75.1% tried to quit. A third of the smoking students (36.8%) found it difficult to stop smoking in no-smoking areas. CONCLUSION: A well-planned integrated antismoking campaign is urgently required, especially among students and teachers. Our study revealed that smoking prevalence was high, which will lead to future high smoking-related health problems if proper preventive measures are not taken accordingly.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Fumar/epidemiologia , Estudantes/estatística & dados numéricos , Adolescente , Adulto , Estudos Transversais , Coleta de Dados , Feminino , Amigos , Humanos , Masculino , Motivação , Prevalência , Arábia Saudita/epidemiologia , Instituições Acadêmicas , Abandono do Hábito de Fumar/estatística & dados numéricos , Inquéritos e Questionários , Poluição por Fumaça de Tabaco , Adulto Jovem
13.
Int J Dent Hyg ; 11(3): 208-15, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23216907

RESUMO

OBJECTIVE: To investigate the association between oral hygiene and dental caries in young children in the Emirate of Ajman, United Arab Emirates. METHODS: A one-stage cluster sample was used to randomly select children. Clinical examinations were conducted by a single examiner. Parents completed questionnaires seeking information on child and family characteristics, dietary habits and oral hygiene practices. RESULTS: The total number of children sampled was 1297. Dental examination and questionnaire data were obtained for 1036 (79.9%). Frequency of eating per day and snack consumption level were both significantly associated with plaque score. Children who brushed their teeth more often had lower plaque scores. The observed association between mean plaque score and mean decayed, missing, filled teeth suggests that children with high plaque scores are more likely to experience caries. CONCLUSIONS: Brushing with fluoride toothpaste was under-utilized in Ajman. Tooth brushing therefore needs better promotion and reinforcement.


Assuntos
Cárie Dentária/patologia , Escovação Dentária/métodos , Escovação Dentária/estatística & dados numéricos , Criança , Pré-Escolar , Índice CPO , Cárie Dentária/epidemiologia , Placa Dentária/epidemiologia , Placa Dentária/prevenção & controle , Comportamento Alimentar , Feminino , Fluoretos/uso terapêutico , Humanos , Masculino , Setor Privado , Setor Público , Análise de Regressão , Instituições Acadêmicas/organização & administração , Lanches , Cremes Dentais/química , Cremes Dentais/uso terapêutico , Emirados Árabes Unidos/epidemiologia
14.
Int J Food Sci ; 2023: 1797017, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37350796

RESUMO

Date pits are agricultural waste byproducts and are available in tons yearly. Milk MUFAs are lipids beneficial for health and sorted out for food product development. This work is aimed at researching the effect of supplementing dairy goats with date pit powder (DPP) as a source of fatty acids (FA), an alternative to enhancing the unsaturated FA in milk and analysed via chemometrics in a 3-month supplementation-based study. Saanen-Boer crossed dairy goats were divided into six groups comprising of control, 10 g and 20 g both for Ajwa DPP (high-quality dates) and Mariami DPP (agricultural waste byproduct), and another 30 g for Mariami DPP only. The supplementation exercise was done daily on each dairy goat. The DPP and milk samples were analysed for its FA profile applying GC-FID and followed by chemometric techniques, namely, PCA and PLS. Results indicated that the n-6/n-3 ratio was the highest for the unsupplemented group compared to the DPP-treated goats with lower n-6/n-3 ratios. The M30 group showcased the most promising health-related class of FAs viewed by 3D PCA and PLS model clustering patterns, in particular monounsaturated FA (MUFA) (C18:1n9c or oleic acid). These results suggest that Mariami DPP supplementation at higher doses and time to lactating Saanen-Boer cross goats can be a means to milk FA quantity and quality enhancement and that chemometrics via pattern recognition can be useful statistical tools when dealing with overwhelming data.

15.
Polymers (Basel) ; 15(2)2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36679271

RESUMO

Despite the advanced development in the field of drug discovery and design, fighting infectious and non-infectious diseases remains a major worldwide heath challenge due to the limited activity of currently used drugs. Nevertheless, in recent years, the approach of designing nanoparticles for therapeutic applications has gained more interest and promise for future use. Thus, the current study is focused on the evaluation of A. judaica extract and chitosan nanoparticles loaded extract (CNPsLE) for potential antimicrobial and anticancer activities. The HPLC analysis of the extract has shown the presence of various phenolic and flavonoid compounds, including kaempferol (3916.34 µg/mL), apigenin (3794.32 µg/mL), chlorogenic acid (1089.58 µg/mL), quercetin (714.97 µg/mL), vanillin (691.55 µg/mL), naringenin (202.14 µg/mL), and rutin (55.64 µg/mL). The extract alone showed higher MIC values against B. subtilis, E. coli, S. aureus, K. pneumonia, and C. albicans (62.5, 15.65, 15.62, 31.25, and 31.25 µg/mL, respectively), whereas lower MIC values were observed when the extract was combined with CNPsLE (0.97, 1.95, 3.9, 4.1, and 15.62 µg/mL, respectively). The extract exhibited low cytotoxicity against normal Vero cells with IC50 173.74 µg/mL in comparison with the cytotoxicity of the CNPsLE (IC50, 73.89 µg/mL). However, CNPsLE showed more selective toxicity against the human prostate cancer cell line (PC3) with IC50 of 20.8 µg/mL than the extract alone with 76.09 µg/mL. In the docking experiments, kaempferol and apigenin were revealed to be suitable inhibitors for prostate cancer (2Q7L). Overall, the obtained data highlighted the promising potential therapeutic use of CNPsLE as an anticancer and antimicrobial agent.

16.
Life (Basel) ; 13(7)2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37511887

RESUMO

It is worth noting that laurel (Laurus nobilis L.) contains several pharmacologically and nutritionally active compounds that may differ according to the pretreatment process. The current study is designed to clarify the effect of moist heat on the phenolic and flavonoid constituents and anti-Helicobacter pylori, antioxidant, antidiabetic, and anti-Alzheimer's activities of laurel leaf extract (LLE). Unmoist-heated (UMH) and moist-heated (MH) LLEs showed the presence of numerous flavonoid and phenolic constituents, although at different levels of concentration. MH significantly induced (p < 0.05) the occurrence of most compounds at high concentrations of 5655.89 µg/mL, 3967.65 µg/mL, 224.80 µg/mL, 887.83 µg/mL, 2979.14 µg/mL, 203.02 µg/mL, 284.65 µg/mL, 1893.66 µg/mL, and 187.88 µg/mL, unlike the detection at low concentrations of 3461.19 µg/mL, 196.96 µg/mL, 664.12 µg/mL, 2835.09 µg/mL, 153.26 µg/mL, 254.43 µg/mL, 1605.00 µg/mL, 4486.02 µg/mL, and 195.60 µg/mL using UMH, for naringenin, methyl gallate, caffeic acid, rutin, ellagic acid, coumaric acid, vanillin, ferulic acid, and hesperetin, respectively. Chlorogenic acid, syringic acid, and daidzein were detected in the UMH LLE but not in the MH LLE, unlike pyrocatechol. The anti-H. pylori activity of the UMH LLE was lower (23.67 ± 0.58 mm of inhibition zone) than that of the MH LLE (26.00 ± 0.0 mm of inhibition zone). Moreover, the values of MIC and MBC associated with the MH LLE were very low compared to those of the UMH LLE. Via MBC/MIC index calculation, the UMH and MH LLEs showed cidal activity. The MH LLE exhibited higher anti-biofilm activity (93.73%) compared to the anti-biofilm activity (87.75%) of the MH LLE against H. pylori. The urease inhibition percentage was more affected in the UMH LLE compared to the MH LLE, with significant (p < 0.05) IC50 values of 34.17 µg/mL and 91.11 µg/mL, respectively. Promising antioxidant activity was documented with a very low value of IC50 (3.45 µg/mL) for the MH LLE compared to the IC50 value of 4.69 µg/mL for the UMH LLE and the IC50 value of 4.43 µg/mL for ascorbic acid. The MH LLE showed significantly higher (p < 0.05) inhibition of α-glucosidase and butyrylcholinesterase activities, with IC50 values of 9.9 µg/mL and 17.3 µg/mL, respectively, compared to those of the UMH LLE at 18.36 µg/mL and 28.92 µg/mL. The molecular docking of naringenin showed good docking scores against acetylcholinesterase 1E66 and butyrylcholinesterase 6EMI, indicating that naringenin is an intriguing candidate for additional research as a possible medication for Alzheimer's disease.

17.
Int J Dent Hyg ; 10(2): 142-6, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22040165

RESUMO

AIM: The aim of this study was to describe self-reported oral health, oral hygiene habits and frequency of visits to a dentist among pregnant women visiting maternity hospitals in the United Arab Emirates. MATERIAL AND METHODS: A cross-sectional study was conducted, with anonymous structured questionnaires distributed to 800 pregnant women who were chosen at random from attendants of three maternity and child health centres from various geographical areas of UAE, during January-March 2010. RESULTS: The response rate was 93.7% (n = 750). Less than quarter of the participated pregnant women were in their first trimester. Almost a quarter (23.5%) of the women believed that they had periodontal problem currently, while 46.3% reported having carious teeth. More than 44% reported having dental pain, and about 40% women felt that her oral health was poor. About 60% reported having heard about the possible connection between pregnancy and the oral health. About 94% of the women were brushing their teeth at least once a day. More than half of the women (58.3%) visited the dentist during their most recent pregnancy, mostly for dental pain. CONCLUSIONS: A large proportion of the pregnant women in this study had oral health problems; however, more than 40% of those women had not visited a dentist during their pregnancy, and the majority of those utilized dental services when they had dental pain only. To provide better oral health care, more knowledge needs to be made available to the pregnant women and the medical community.


Assuntos
Assistência Odontológica/estatística & dados numéricos , Conhecimentos, Atitudes e Prática em Saúde , Higiene Bucal/estatística & dados numéricos , Doenças Periodontais/prevenção & controle , Complicações na Gravidez/prevenção & controle , Adolescente , Adulto , Estudos Transversais , Autoavaliação Diagnóstica , Feminino , Doenças da Gengiva/prevenção & controle , Humanos , Saúde Bucal , Gravidez , Autorrelato , Emirados Árabes Unidos , Adulto Jovem
18.
Biomolecules ; 12(10)2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36291570

RESUMO

Due to the concerning rise in the number of multiple- and prolonged-drug-resistant (MDR and XDR) Mycobacterium tuberculosis (Mtb) strains, unprecedented demand has been created to design and develop novel therapeutic drugs with higher efficacy and safety. In this study, with a focused view on implementing an in silico drug design pipeline, a diverse set of glycosylated flavonoids were screened against the Mtb cytochrome-P450 enzyme 121 (CYP121), which is established as an approved drug target for the treatment of Mtb infection. A total of 148 glycosylated flavonoids were screened using structure-based virtual screening against the crystallized ligand, i.e., the L44 inhibitor, binding pocket in the Mtb CYP121 protein. Following this, only the top six compounds with the highest binding scores (kcal/mol) were considered for further intermolecular interaction and dynamic stability using 100 ns classical molecular dynamics simulation. These results suggested a considerable number of hydrogen and hydrophobic interactions and thermodynamic stability in comparison to the reference complex, i.e., the CYP121-L44 inhibitor. Furthermore, binding free energy via the MMGBSA method conducted on the last 10 ns interval of MD simulation trajectories revealed the substantial affinity of glycosylated compounds with Mtb CYP121 protein against reference complex. Notably, both the docked poses and residual energy decomposition via the MMGBSA method demonstrated the essential role of active residues in the interactions with glycosylated compounds by comparison with the reference complex. Collectively, this study demonstrates the viability of these screened glycosylated flavonoids as potential inhibitors of Mtb CYP121 for further experimental validation to develop a therapy for the treatment of drug-resistant Mtb strains.


Assuntos
Mycobacterium tuberculosis , Mycobacterium tuberculosis/metabolismo , Ligantes , Flavonoides/farmacologia , Flavonoides/metabolismo , Ligação Proteica , Sistema Enzimático do Citocromo P-450/metabolismo , Inibidores das Enzimas do Citocromo P-450/farmacologia , Inibidores das Enzimas do Citocromo P-450/metabolismo , Simulação de Dinâmica Molecular , Hidrogênio/metabolismo
19.
J Exp Biol ; 214(Pt 23): 3924-34, 2011 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-22071183

RESUMO

Acoustically interacting males of the tropical katydid Mecopoda elongata synchronize their chirps imperfectly, so that one male calls consistently earlier in time than the other. In choice situations, females prefer the leader signal, and it has been suggested that a neuronal mechanism based on directional hearing may be responsible for the asymmetric, stronger representation of the leader signal in receivers. Here, we investigated the potential mechanism in a pair of interneurons (TN1 neuron) of the afferent auditory pathway, known for its contralateral inhibitory input in directional hearing. In this interneuron, conspecific signals are reliably encoded under natural conditions, despite high background noise levels. Unilateral presentations of a conspecific chirp elicited a TN1 response where each suprathreshold syllable in the chirp was reliably copied in a phase-locked fashion. Two identical chirps broadcast with a 180 deg spatial separation resulted in a strong suppression of the response to the follower signal, when the time delay was 20 ms or more. Muting the ear on the leader side fully restored the response to the follower signal compared with unilateral controls. Time-intensity trading experiments, in which the disadvantage of the follower signal was traded against higher sound pressure levels, demonstrated the dominating influence of signal timing on the TN1 response, and this was especially pronounced at higher sound levels of the leader. These results support the hypothesis that the female preference for leader signals in M. elongata is the outcome of a sensory mechanism that originally evolved for directional hearing.


Assuntos
Gryllidae/fisiologia , Neurônios/fisiologia , Vocalização Animal/fisiologia , Estimulação Acústica , Animais , Audiometria de Tons Puros , Limiar Auditivo/fisiologia , Feminino , Masculino , Gravação em Fita , Fatores de Tempo , Árvores
20.
Eur J Paediatr Dent ; 12(2): 99-102, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21668280

RESUMO

AIM: To assess, by means of self-administered structured questionnaire, the level of knowledge of primary schools teachers in Ajman with regards to the immediate emergency management of dental trauma. MATERIALS AND METHODS: The questionnaire was sent to teachers in randomly selected primary schools in Ajman. A total of 161 teachers responded (response rate 84.4%). The questionnaire surveyed teachers' background, knowledge and management of tooth fracture, avulsion, and also investigated teachers' attitudes and self-assessed knowledge. RESULTS: Ninety-one percent of the teachers were females, 51.6% in their thirties and 61.5% had university qualification. Fifty teachers had received formal first aid training, and only thirteen of them recalled that they had received training on the management of dental trauma. Concerning the management of tooth fracture, 138 respondents (85.8%) gave the appropriate management for fractured tooth. One hundred twenty-one (75%) of the respondents indicated that is very urgent to seek professional assistance if a permanent tooth is avulsed, but they had little knowledge on the correct media for transporting the avulsed tooth. Most teaches were unsatisfied with their level of knowledge for dental trauma and the majority were interested in having further education on the topic. CONCLUSION: The findings revealed that the level of knowledge of management of dental trauma (especially tooth avulsion) among school teachers in Ajman is inadequate, and education campaigns are necessary to improve their emergency management of dental injuries.


Assuntos
Tratamento de Emergência/métodos , Instituições Acadêmicas , Ensino , Traumatismos Dentários/terapia , Adulto , Atitude Frente a Saúde , Escolaridade , Feminino , Primeiros Socorros , Educação em Saúde Bucal , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Soluções para Preservação de Órgãos/uso terapêutico , Autoimagem , Fatores de Tempo , Avulsão Dentária/terapia , Fraturas dos Dentes/terapia , Emirados Árabes Unidos , Adulto Jovem
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