Antibacterial,antibiofilm, and antiquorum sensing activities of phytosynthesized silver nanoparticles fabricated from Mespilus germanica extract against multidrug resistance of Klebsiella pneumoniae clinical strains

The aim of the present work was to investigate the antibacterial, antibiofilm, and antiquorum sensing activities of phytosynthesized silver nanoparticles (AgNPs) fabricated from Mespilus germanica extract against multidrug-resistant (MDR) Klebsiella pneumoniae strains. Fifty strains of K. pneumoniae were isolated from various clinical specimens. Biofilm-forming strains were identified using Congo red agar and polymerase chain reaction (PCR) techniques. Subsequently, the antibacterial activity of phytosynthesized AgNPs on MDR K. pneumoniae strains was investigated by broth microdilution assay and agar well-diffusion method. Finally (in the last step), the antibiofilm activity of phytosynthesized AgNPs was determined using microtiter plate assay and real-time PCR (RT-PCR) methods for the analysis of type 3 fimbriae (mrkA) and quorum-sensing system (luxS) gene expression. The results of this study showed that the phytosynthesized AgNPs had a spherical nanostructure with the mean size of 17.60 nm. The AgNPs exhibited dose-dependent antibacterial activity. The results of the microtiter plate and RT-PCR methods show that AgNPs inhibited the biofilm formation in MDR K. pneumoniae strains, and the expressions of mrkA and luxS genes were downregulated significantly in MDR strains after treatment with a subminimum inhibitory concentration of AgNPs. In conclusion, AgNPs effectively prevent the formation of biofilms and kill bacteria in established biofilms, which suggests that AgNPs might be a promising candidate for the prevention and treatment of biofilm-related infections caused by MDR K. pneumoniae strains.     

The influence of mental fatigue on brain activity: Evidence from a systematic review with meta-analyses

The occurrence of mental fatigue during tasks like driving a vehicle increases risk of injury or death. Changes in electroencephalographic (EEG) activity associated with mental fatigue has been frequently studied and considered a promising biomarker of mental fatigue. This is despite differences in methodologies and outcomes in prior research. A systematic review with meta-analyses was conducted to establish the influence of mental fatigue on EEG activity spectral bands, and to determine in which regions fatigue-related EEG spectral changes are likely to occur. A high-yield search strategy identified 21 studies meeting inclusion criteria for investigating the change in EEG spectral activity in non-diseased adults engaged in mentally fatiguing tasks. A medium effect size (using Cohen's g) of 0.68 (95%CI: 0.24–1.13) was found for increase in overall EEG activity following mental fatigue. Further examination of individual EEG spectral bands and regions using network meta-analyses indicated large increases in theta (g = 1.03; 95%CI: 0.79–1.60) and alpha bands (g = 0.85; 95%CI: 0.47–1.43), with small to moderate changes found in delta and beta bands. Central regions of the scalp showed largest change (g = 0.80; 95%CI: 0.46–1.21). Sub-group analyses indicated large increases in theta activity in frontal, central and posterior sites (all g > 1), with moderate changes in alpha activity in central and posterior sites. Findings have implications for fatigue monitoring and countermeasures with support for change in theta activity in frontal, central and posterior sites as a robust biomarker of mental fatigue and change in alpha wave activity considered a second line biomarker to account for individual variability.     

Cardiac sympathetic activation and parasympathetic withdrawal during psychosocial stress exposure in 6-month-old infants

Infant autonomic reactivity to stress is a potential predictor of later life health complications, but research has not sufficiently examined sympathetic activity, controlled for effects of physical activity and respiration, or studied associations among autonomic adjustments, cardiac activity, and affect in infants. We studied 278 infants during the repeated Still-Face Paradigm, a standardized stressor, while monitoring cardiac activity (ECG) and respiratory pattern (respiratory inductance plethysmography). Video ratings of physical activity and affect were also performed. Respiratory sinus arrhythmia (RSA) and T-wave amplitude (TWA) served as noninvasive indicators of cardiac parasympathetic and sympathetic activity, respectively. Responses were compared between infants who completed two still-face exposures and those who terminated after one exposure due to visible distress. Findings, controlled for physical activity, showed robust reductions in respiration-adjusted RSA and TWA, with more tonic attenuation of TWA. Infants completing only one still-face trial showed more pronounced autonomic changes and less recovery from stress. They also showed elevated minute ventilation, suggesting hyperventilation. Both reductions in adjusted RSA and TWA contributed equally to heart rate changes and were associated with higher negative and lower positive affect. These associations were more robust in the group of distressed infants unable to complete both still-face trials. Thus, cardiac sympathetic activation and parasympathetic withdrawal are part of the infant stress response, beyond associated physical activity and respiration changes. Their association with cardiac chronotropy and affect increases as infants' distress level increases. This excess reactivity to social stress should be examined as a predictor of future cardiovascular disease.     

Relationship of regular physical activity with neuroelectric indices of interference processing in young adults

The relationship of physical activity with interference processing was examined using behavioral and neuroelectrical measures in young adults divided into more active and less active groups. The participants completed Stroop (i.e., color-naming) and reverse Stroop (i.e., word-meaning) tasks that differed in the level of difficulty while event-related potentials were assessed. In the low interference Stroop task, participants were asked to respond to the ink color of the word, while the meaning was either congruent or incongruent with the color. In the high interference reverse Stroop task, participants had to indicate the meaning of colored words while ignoring the color of the font. The results indicated that young adults in the more active group exhibited a shorter response time (RT) and a lower intra-individual variability of RT than did those in the less active group. These behavioral differences were associated with larger P2 and P3 and smaller N450 amplitudes in the Stroop task and with larger P2 and N2 and smaller N450 amplitudes in the reverse Stroop task. No differences were observed in the contingent negative variation (CNV) between the groups. These findings suggest that, for young adults, regular physical activity is positively associated with a better neural efficiency in resource allocation for tasks that require the ability to inhibit cognitive interference and provide evidence for the potential neural mechanisms underlying the improved Stroop performance.     

Association between sexuality knowledge and sexual dysfunction in hematopoietic stem cell transplantation patients and their partners

ObjectiveTo evaluate the association of sexual knowledge with sexual desire, sexual activity, and sexual satisfaction in hematopoietic stem cell transplantation (HSCT) patients and partners, and their willingness to participate in sexual education.MethodsThis is a multi-center survey. Patients were eligible if they had received HSCT. Patients’ current sexual partners were invited to the study unless they had limitations on sexual activity. Sexual desire, activity and satisfaction was assessed using the Sexual Activity Questionnaire. Sexual knowledge, experience of information seeking, sexual counseling or education, and willingness of participate in sexual education were assessed using questionnaire.ResultsOf 151 participants, 61.8 % had experience of receiving counseling about their sexual issues after HSCT. Compared to the lower sexual knowledge group, participants with higher sexual knowledge reported to be 1.91 times more sexually active with 3.04 times higher sexual desire. Among the participants, 79.4 % of participants had the willingness to receive sexual education after HSCT and preferred to receive sexual education from sexual education specialistsConclusionsHigher sexual knowledge was associated with higher sexual desire, sexual activity, and sexual satisfaction.Practice implicationsSexual education should be provided to patients and their partners after HCST by trained experts for HSCT patient’s sexual life.     

体育运动对孤独症谱系障碍的干预

孤独症谱系障碍是以社会交往障碍、兴趣狭隘和重复刻板行为为特征的神经发育疾病。目前,其发病机制还没有被完全认知,临床上采用多种方法进行治疗与干预,其中体育运动干预也有明显的效果。针对体育运动对孤独症谱系障碍症状的改善做一综述,为后续研究提供理论支持。     

Association between serum Toll-like receptor 4 and 8-hydroxy-2′-deoxyguanosine levels with disease activity in rheumatoid arthritis patients

Aim of the workConsidering the importance of toll-like receptor (TLR) 4 and oxidative stress in the pathogenesis of autoimmune disorders, present study was designed to assess serum TLR4, 8-hydroxy-2′-deoxyguanosine (8-OHdG) as a marker of oxidative DNA damage, and total antioxidant capacity (TAC) in rheumatoid arthritis (RA) patients and to study their relation with disease activity and their predictive potential.Patients and methods44 RA patients and 44 matched controls were studied. Disease activity score (DAS-28) was assessed. Serum TLR4, 8-OHdG and TAC were measured.ResultsThe mean age of patients was 44 ± 10.4 years, 33 females and 11 males with and disease duration 5.5 ± 3.8 months. The mean DAS-28 was 4.6 ± 0.6 (3.45–6.01). Rheumatoid factor (RF) and anti-cyclic citrullinated peptide (anti-CCP) were both positive in 20 patients. Compared to control, the mean ± SD of serum TLR4 (2.41 ± 4.50 vs. 1.20 ± 1.67 ng/ml), and 8-OHdG (67.67 ± 20.57 vs. 45.34 ± 30.61 ng/ml) were significantly higher in patients (p < 0.001); whilst serum TAC (1.3 ± 0.5 vs. 2.01 ± 0.55 µmol/L) was significantly lower (p < 0.001). TLR4, 8-OHdG were significantly increased and TAC decreased in patients with positive RF/anti-CCP compared to negative (p < 0.001, p = 0.005 and p = 0.036 respectively). TLR4 was significantly higher in patients with higher DAS-28 (p = 0.003) and both significantly correlated (p < 0.001). Areas under the ROC curve of TLR4 (0.87; 95%CI: 0.78–0.96) and 8-OHdG (0.88; 95%CI: 0.79–0.97) were greater than that of TAC (0.19, 95%CI: 0.09–0.29) (p < 0.001).ConclusionThe TLR4, 8-OHdG and TAC showed high predictive value in RA disease. TLR4 can be remarked as a sensitive and specific marker for determining disease activity in RA.     

Serum and synovial fluid interleukin-17 concentrations in rheumatoid arthritis patients: Relation to disease activity,radiographic severity and power Doppler ultrasound

Aim of the workTo investigate serum and synovial fluid levels of IL-17 in rheumatoid arthritis (RA) patients, and its correlation with disease activity and severity.Patients and methods20 RA patients together with 20 primary knee osteoarthritis (KOA) patients and 15 healthy individuals matched for age and sex as control groups were enrolled in this study. Both RA and KOA patients presented with knee effusion. Paired samples of serum and synovial fluid (SF) were collected from RA, OA patients and serum samples from the healthy individuals. RA disease activity was assessed using DAS-28 score and power Doppler ultrasound (PDUS) according to the European League against Rheumatism (EULAR). Radiographic damage was evaluated according to Larsen score.ResultsSerum levels of IL-17 were significantly elevated in RA patients compared to controls (p < 0.001). Also, SF of IL-17 was significantly higher in RA patients compared to OA patients (p < 0.001). In addition, synovial level of IL-17 was significantly higher in RA patient compared to their serum level (p < 0.001). Regarding disease activity grading among RA patients, significant differences (p < 0.05) in mean serum and synovial IL-17 levels were reported being higher in severe active disease. Positive correlations of serum and SF IL 17 levels with PDUS findings and Larsen score were reported.ConclusionSerum and synovial IL-17 levels were significantly elevated in RA patients which clarifies its possible role in RA pathogenesis and correlates positively with disease activity parameters, PDUS findings and Larsen score. Thus targeting IL-17 may provide a promising role in suppressing RA.