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Rapid and accurate detection of viable bacteria is essential for the clinical diagnosis of urinary tract infections (UTIs) and for making effective therapeutic decisions. However, most current molecular diagnostic techniques are unable to differentiate between viable and non-viable bacteria. In this study, we introduce a novel isothermal platform that integrates strand exchange amplification (SEA) with the CRISPR/Cas12a system, thereby enhancing both the sensitivity and specificity of the assay and achieving detection of phage DNA at concentrations as low as 4 × 10 2 copies per μL. Moreover, the incorporation of phages facilitates the specific recognition of viable bacteria and amplifies the initial signal through the inherent specificity and propagation properties of these phages. By employing the phage-assisted SEA-Cas12a approach, we successfully detected viable bacteria in human urine samples without the necessity of DNA extraction within 3.5 hours, achieving a detection limit of 10 3 CFU per mL. Considering its speed, accuracy, and independence from specialized equipment, this platform demonstrates significant potential as a robust tool for the rapid detection of various pathogens in resource-limited settings, thereby facilitating timely clinical management of UTI patients.

To investigate the impact of various self-acid corrosion adhesives in restoring ring caries in anterior deciduous teeth and the influencing factors of childhood caries. This study retrospectively analyzed the repair effect of two kinds of restoration schemes on the annular caries of children's deciduous anterior teeth. According to the repair scheme, 54 children with caries were divided into two groups. The children with 3M single bond repair were set as the control group, and the children with Clearfil SE Bond 2 repair were set as the study group. The repair effect of 6 months and 12 months of treatment and the treatment satisfaction of children were compared. Additionally, 50 children with no oral abnormalities were included as a healthy control group to analyze dental caries risk factors comparatively. The retention of dental restorations, marginal adaptation to dentin, and dental pulp vitality scores in the study group were significantly lower than those in the control group at both 6 and 12 months post-treatment, with statistically significant differences ( p < 0.05). Moreover, satisfaction levels in the study group notably exceeded those in the control group (92.59% vs. 70.37%). Fisher exact test yielded a p value of 0.041. Binary logistic regression analysis revealed that daily tooth brushing habits and parental supervision were protective against dental caries occurrence. Conversely, plaque, dental calculus, proficiency in tooth brushing techniques, and post-brushing bedtime snacking emerged as independent risk factors for dental caries ( p < 0.05). Compared to the conventional self-etching dentin adhesive filling regimen, the novel blended adhesive and composite resin filling significantly enhanced dental caries restoration outcomes and increased children's satisfaction. Notably, this approach was well-received by both children and their families. Further proactive measures targeting children with identified risk factors are warranted to reduce the incidence of dental caries., Competing Interests: The authors declare no conflict of interest., (©2024 The Author(s). Published by MRE Press.)

Background: Cinnamomum camphora is a commercially important tree species in China, and it's also a common native tree in the forests of southern China. However, literature on the impact of Cinnamomum camphora essential oil (CCEO) on human psychophysiological activity is scarce. Hence, the primary objective of this study was to examine the effect of exposure to CCEO on the functioning of the human autonomic nervous system, electroencephalographic (EEG) activity, and emotional state., Methods: Forty-three healthy university students participated. The data collected included heart rate (HR), blood pressure (BP), pulse rate, blood oxygen saturation (SpO 2 ), electroencephalographic (EEG) activity, and the results of the Profile of Mood States (POMS) test., Results: A drop in diastolic pressure (DBP) and pulse rate was also noticed after participants inhaled CCEO. Furthermore, EEG studies have demonstrated notable reductions in absolute beta (AB), absolute gamma (AG), absolute high beta (AHB), and relative gamma (RG) power spectra during exposure to CCEO. Conversely, the relative theta (RT) and power spectra values showed a significant increase. Additionally, the finding from POMS indicated that the fragrance evoked positive emotions and suppressed negative feelings., Conclusion: The results suggest that exposure to CCEO may promote mental and physical relaxation, facilitate cognitive processes such as memory and attention, and enhance mood states., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Gong, Yang, Xu, Yao, Lin and Chang.)

Recent theoretical and experimental findings have demonstrated the minimum characteristic in the harmonic spectrum of bulk MgO crystals subjected to intense laser pulses. However, the dominant mechanism behind this minimum structure is still under debate. This study simulates the harmonic spectrum from a MgO crystal in a linearly polarized laser pulse by solving multi-band semiconductor Bloch equations. The results show that the minimum feature at 20 eV in the MgO harmonic spectra from 1700 and 800 nm laser pulses is due to band dispersion and interference between interband harmonics. Notably, the disappearance of the minimum structure at 14 eV in the harmonic spectrum from the 800 nm laser is attributed to the intensity suppression of higher energy harmonics, caused by decreased electron population at the boundary of the first Brillouin zone in the multi-band case. These findings offer insights into the spectral structure of solid-state harmonics, contributing to the all-optical reconstruction of the crystal band based on its harmonic spectrum.

As CRISPR technology is promoted to more fine-divided molecular biology applications, its inherent performance finds it increasingly difficult to cope with diverse needs in these different fields, and how to more accurately control the performance has become a key issue to develop CRISPR technology to a new stage. Herein, we propose a CRISPR/Cas12a regulation strategy based on the powerful programmability of nucleic acid nanotechnology. Unlike previous difficult and rigid regulation of core components Cas nuclease and crRNA, only a simple switch of different external RNA accessories is required to change the reaction kinetics or thermodynamics, thereby finely and almost steplessly regulating multi-performance of CRISPR/Cas12a including activity, speed, specificity, compatibility, programmability and sensitivity. In particular, the significantly improved specificity is expected to mark advance the accuracy of molecular detection and the safety of gene editing. In addition, this strategy was applied to regulate the delayed activation of Cas12a, overcoming the compatibility problem of the one-pot assay without any physical separation or external stimulation, and demonstrating great potential for fine-grained control of CRISPR. This simple but powerful CRISPR regulation strategy without any component modification has pioneering flexibility and versatility, and will unlock the potential for deeper applications of CRISPR technology in many finely divided fields., (© The Author(s) 2023. Published by Oxford University Press on behalf of Nucleic Acids Research.)

Efficient enhancement of harmonic brightness near the cutoff region is achieved by employing laser pulses with a small positive chirp in theory, where the laser intensity and frequency near the peak of the laser pulse are almost unchanged relative to the chirp-free field. The improvement of harmonic brightness is achieved under the condition that the ionization probability is almost unchanged. Through the analysis of the harmonics contributed by the rising and falling parts of the laser pulse, we have uncovered a "frequency compensation" mechanism that leads to an enhanced harmonic brightness near the cutoff region. Under appropriate chirp parameters, the harmonics contributed by the rising and falling parts can be constructively interfered in a smaller frequency range with greater intensity, thereby obtaining harmonics with good monochromaticity and high brightness. This study explains the mechanism of harmonic brightness enhancement from a new perspective, and provides a new idea for harmonic regulation without changing the ionization.

Transdermal drug delivery system (TDDS) has attracted much attention in the pharmaceutical technology area. However, the current methods are difficult to ensure penetration efficiency, controllability, and safety in the dermis, so its widespread clinical use has been limited. This work proposes an ultrasound-controlled monodisperse lipid vesicles (U-CMLVs) hydrogel dressing, which combines with ultrasound to form TDDS. Using microfluidic technology, prepare size controllable U-CMLVs with high drug encapsulation efficiency and quantitative encapsulation of ultrasonic response materials, and even uniform mix them with hydrogel to prepare the required thickness of dressings. The high encapsulation efficiency can ensure sufficient dosage of the drugs and further realize the control of ultrasonic response through quantitative encapsulation of ultrasound-responsive materials. Using high frequency (5 MHz, 0.4 W cm -2 ) and low frequency (60 kHz, 1 W cm -2 ) ultrasound to control the movement and rupture of U-CMLVs, the contents not only penetrate the stratum corneum into the epidermis but also break through the bottleneck of penetration efficiency, and deep into the dermis. These findings provide the groundwork for deep, controllable, efficient, and safe drug delivery through TDDS and lay a foundation for further expanding its application., (© 2023 Wiley-VCH GmbH.)

Copper (Cu) is an inexpensive transition metal on Earth, exhibiting high catalytic activity due to its rich d-electron configuration and variable oxidation states. Cu-based biological alloys and nanocomposites have emerged as a prominent research area. Under specific synthesis conditions, alloys or nanocomposites formed by Cu with other metals demonstrate excellent enzyme-like and sensing activities. These advanced materials offer significant advantages over artificial enzymes in enzymatic applications, including high stability, simple synthesis, flexible catalytic performance, and ease of preservation. In addition, various types of sensors have been designed based on the unique electrochemical properties exhibited by these alloys and nanocomposites as well as their specific reactions with the target substances. These sensors possess advantages such as stability, high efficiency, a broad detection range, low detection limits, and high sensitivity. In this review, we summarize the current research status of Cu-based biological alloys and nanocomposites in enzyme-like applications and sensing applications. Based on this, we introduce the diverse enzyme-like activities exhibited by Cu-based nanozymes prepared under different synthesis conditions and their applications in areas such as biosensing, cancer treatment, and antibacterial therapy. Furthermore, we provide an overview of the applications of Cu-based alloys and nanocomposites in the field of sensing based on their enzyme-like activity or chemical activities. These sensors have been widely employed in biomedical detection, environmental hazardous substance monitoring, and food safety testing. Challenges and prospects faced by Cu-based alloys and nanocomposites are also highlighted for future works.

The photoelectron emission spectra generated by the interaction between ultrashort intense laser pulses and atoms can reveal the ultrafast dynamics of electrons. By using the numerical solution of the time-dependent Schrödinger equation in momentum space, the photoelectron emission spectra of atoms irradiated by 400 nm intense lasers with different durations of the pulse has been investigated. In the photoelectron emission spectrum, in addition to the above-threshold ionization peaks due to ionization interference in multiple cycles and the sideband peaks mainly due to the interference of ionized electrons at different moments along the rising edge of the laser pulse envelope, additional peaks of photoelectron emission whose intensity appears to oscillate with the increasing duration of the laser pulse can also be observed. Based on strong-field approximation and the population's analysis of the bound state, it is found that these photoelectron peaks originate from the ionization of the excited state and the oscillations of these peaks are due to the superposition of their peak energy positions with the sideband energy positions. Furthermore, it is demonstrated that the energy positions of the maximum intensity of the photoelectron emission spectra move towards the higher energy end as the duration of the driving laser pulse extends. This phenomenon can be attributed to the fact that the main moment of ionization of atoms changes with the increasing duration of the driving laser pulse, thus allowing the real-time ionization of atoms to be probed using photoelectron emission spectra.

The fungus Xylaria sp. KYJ-15 was isolated from Illigera celebica. Based on the one strain many compounds (OSMAC) strategy, the strain was fermented on potato and rice solid media, respectively. As a result, two novel steroids, xylarsteroids A (1) and B (2), which are the first examples of C 28 -steroid with an unusual β- and γ-lactone ring, respectively, along with two new dihydroisocoumarin glycosides, xylarglycosides A (3) and B (4), were identified. Their structures were elucidated by spectroscopic methods, X-ray diffraction and electronic circular dichroism (ECD) experiments. All isolated compounds were evaluated for cytotoxicity, DPPH radical scavenging activity, acetylcholinesterase inhibitory and antimicrobial effect. Compound 1 exhibited potent AChE inhibitory activity with an IC 50 value of 2.61 ± 0.05 μmol·L -1 . The β-lactone ring unit of 1 is critical for its AChE inhibitory activity. The finding was further confirmed through exploring the interaction of 1 with AChE by molecular docking. In addition, both compounds 1 and 2 exhibited obvious antibacterial activity against Bacillus subtilis with a minimum inhibitory concentration (MIC) of 2 μg·mL -1 . Compounds 3 and 4 exhibited antibacterial activities against Staphylococcus aureus with MICs of 4 and 2 μg·mL -1 , respectively, which also exhibited DPPH radical scavenging activity comparable to the positive control with IC 50 values of 9.2 ± 0.03 and 13.3 ± 0.01 μmol·L -1 , respectively., (Copyright © 2023 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.)

During the process of the high-speed urbanization in Chinese cities, the social, economic, and political status and the interaction between each factor have been more focused on urban traditional district renewal. However, the effects on urban microclimate and the residential living conditions in traditional districts are not well discussed, which is strongly related to the living comfort and citizens' well-being. In this study, two typical traditional districts in Xi'an are selected. According to the original situation of building functions and the community characteristics, two renewal plans are proposed by adding vegetation in open spaces (V), and adding vegetation combined with building redevelopment (V&B), in order to balance the living convenience and thermal environment. Via ENVI-met simulation, the effects of the district renewal plans on thermal environment including wind speed, air temperature, and mean radiant temperature are evaluated. This study provides method of environmental evaluation for traditional district renewal, which contributes to sustainable urban planning in historical districts, and provides recommendations for related policy development., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Reliable and cost-effective quantification of RNA modifications at a specific gene locus is essential to elucidate the pathogenic mechanism encoded by RNA epigenetics. Current methods to quantify N 6 -methyladenosine (m6A) at specific sites can hardly satisfy the requirement of clinical application because epigenetic information is easily lost through polymerase chain reaction (PCR) assay or other isothermal amplification methods unless tedious pretreatment is applied. Herein, we propose a simple xeno nucleic acid (XNA) as a blocker probe to mediate the methylation specific reverse transcription quantitative polymerase chain reaction (MsRT-qPCR) assay to directly magnify the minor differences between epigenetic bases and unmodified bases in RNA. Strand displacement reactions selectively initiated between the reverse transcription primer (RT-primer) and the XNA probe at the m6A template given the affinity differences between the blocker probes and the m6A-modified RNA (m6A-RNA) and unmodified RNA (A-RNA). Thus, preferential amplification of m6A-RNA was allowed. Integration of a well-established oligo-modified Fe 3 O 4 @UiO-66-NH 4 allowed purification of mRNA and lncRNA from cellular total RNA samples and greatly reduced the non-specific interference of m6A detection in real samples. Multiple specific sites of m6A in mRNA and lncRNA samples are also successfully quantified. The XNA probe-based m6A assay required only common and available lab equipment and materials, which can be applied in m6A-related fundamental studies and clinical diagnosis.

N 6 -Methyladenosine (m 6 A) is the most abundant RNA modification in eukaryotic messenger RNA (mRNA). A highly sensitive electrochemical immunosensor is described for the determination of m 6 A-RNA. The method is based on the use of antibody (anti-m 6 A) and PtCo mesoporous nanospheres (MPNs). The analogously modified probe of type m 6 A-DNA-PtCo competes with m 6 A-RNA for antibodies on the gold electrode as an electrical signal probe. The electrical signal, best acquired at a working potential of -0.37 V (vs. Ag/AgCl) reflects the concentration of m 6 A. The PtCo MPNs catalyze the reduction of H 2 O 2 , and this amplifies the current and enhances sensitivity. The detection time of the assay is <1.5 h. Under optimal conditions, response is linear in the 0.005 to 100 nM m 6 A RNA concentration range, and the detection limit is 2.1 pM. The results obtained by this immunoassay with human cell lines are comparable to those obtained with a commercial kit. Graphical abstractSchematic representation of a method for electrochemical determination of m 6 A-modified mRNA. Anti-m 6 A Ab: antibody against m 6 A; BSA: bovine serum albumin; PtCo: PtCo mesoporous nanospheres; SH-m 6 A-DNA: DNA modified with both m 6 A and thiol groups; DPV: differential pulse voltammetry.

Strong field double ionization that triggers the chemical bond rearrangement of CH 3 Cl is investigated by impulsive control of the alignment of molecules. The alignment and laser intensity dependent H 2 + and H 3 + yields in linearly polarized femtosecond laser have been measured, and the obtained data show that the maximum signal of H 2 + appears at the laser polarization parallel to the C-Cl axis of molecules and H 3 + species are more likely to eject at the laser polarization parallel to the C-Cl axis at low laser intensity while the H 3 + signal peaks at laser polarization perpendicular to the C-Cl axis at high laser intensity. The measurements indicate that electrons from HOMO - 1 and HOMO - 2 orbitals have been ionized for the generation of bond rearrangement at different laser intensity. Our results demonstrate the importance of multielectron effects and also provide an effective control method in the process of chemical bond rearrangement of the molecules in strong laser fields.

Objective: To explore the role of silent information regulator 1 (SIRT1) signaling pathway in mediating the effect of dexmedetomidine (DEX) to alleviate postoperative cognitive dysfunction (POCD) in aged rats., Methods: Seventy-two healthy male Sprague-Dawley rats aged 18-20 months (weighing 500-700 g) were randomized equally into normal control group, POCD model group, DEX pretreatment group, and DEX and SIRT1 inhibitor (EX527) pretreatment group. In the latter 2 groups, DEX (25 μg/kg) was injected intraperitoneally in the rats 30 min before the operation, and normal saline was injected instead in the other 2 groups; in EX527 group, EX527 (1 μg/kg) was injected intravenously 5 min before the operation. In all but the control group, the rats were subjected to laparotomy lasting 30 min, and on days 1, 3, and 5 following the operation, 6 rats were randomly selected from each group for Morris water maze test to evaluate their cognitive functions. Immediately after the test, the rats were sacrificed and the hippocampus was collected for determination of the levels of tumor necrosis factor- α (TNF- α ) and interleukin-6 (IL-6) using ELISA; Western blotting was used to detect the expression of SIRT1 and nuclear factor- κB (NF-κB) in the hippocampal neurons., Results: Compared with the control rats, the rats in POCD group and EX527 group showed significantly prolonged escape latency, decreased frequency of crossing the original platform, increased TNF- α and IL-6 levels, lowered SIRT1 expression in the hippocampal neurons, and increased NF-κB expression ( P &lt; 0.05), and these parameters were comparable between POCD group and EX527 group ( P &gt; 0.05). DEX pretreatment significantly alleviated cognitive dysfunction and attenuated the changes in TNF- α , IL-6, SIRT1, and NF-κB expressions induced by the operation ( P &lt; 0.05), and EX527 pretreatment of the rats obviously blocked the effects of DEX ( P &lt; 0.05)., Conclusions: DEX alleviates POCD in aged rats probably via SIRT1 signaling pathway.

Objective: To observe the diagnostic value of high-sensitivity C-reactive protein/albumin ratio (hs-CRP/ALB) in early-onset infection in premature and its clinical significance., Methods: Clinical data of premature patients with high risk factors of intrauterine infection admitted to neonatal intensive care unit (NICU) of Liaocheng People's Hospital in Shandong Province from July 2013 to July 2015 were analyzed retrospectively. They were divided into infection and non-infection groups, as well as survival and death groups according to the outcome of the premature babies. The pre-albumin (PA), ALB, white blood cell count (WBC), platelet count (PLT), and hs-CRP at the moment of NICU admission (0 hour) and 24, 48 and 72 hours after NICU admission were compared. The receiver operating characteristic (ROC) curve was plotted for evaluation of the predictive value of serum hs-CRP/ALB ratio for the babies during hospitalization., Results: A total of 214 cases of premature infants were enrolled, with 102 cases in infection group, and 112 in non-infection group. In infection neonates, 97 of them survived, and 5 died. (1) The level of hs-CRP after NICU admission was increased in infection and non-infection groups, and it was significantly higher at 48 hours in infection group than that of the non-infection group [mg/L: 22.0 (7.6, 40.4) vs. 18.3 (12.9, 23.4),Z = 5.257,P = 0.038]. Then hs-CRP was decreased in non-infection, but it was persistently increased in infection group, and it was significantly higher at 72 hours in infection group than that of the non-infection group [mg/L: 25.5 (9.8, 43.5) vs. 12.2 (1.9, 22.1), Z = 5.879, P = 0.042]. The levels of ALB and WBC in infection group was significantly lower than those of the non-infection group [ALB (g/L): 27.9±2.7 vs. 29.1±2.9, t = 5.178, P = 0.026; WBC (×109/L): 13.7±7.1 vs. 16.1±7.9, t = 4.368, P = 0.037], and at 48 hours hs-CRP/ALB in infection group was significantly higher than that of non-infection group [0.16 (0.08, 0.57) vs. 0.07 (0.00, 0.23), Z = 3.436, P = 0.042]. There was no significant difference in PA and PLT between infection and non-infection groups. (2) In premature patients with infection, ALB in non-survival group was decreased (g/L: 20.4±6.9 vs. 29.6±7.5, t = 7.859, P = 0.003), and 48-hour hs-CRP and hs-CRP/ALB ratio was significantly increased when compared with that of survival group [hs-CRP (mg/L): 25.8 (15.6, 54.8) vs. 18.2 (12.9, 36.2), Z = 4.067, P = 0.043; hs-CRP/ALB: 0.31 (0.28, 0.76) vs. 0.06 (0.00, 0.21), Z = 6.102, P = 0.011].(3) It was shown by ROC curve analysis that the area under ROC curve (AUC) of 48-hour hs-CRP/ALB ratio for evaluating infection was 0.765, when the cut-off of 48-hour hs-CRP/ALB ratio was 0.08, the sensitivity was 84.2%, and the specificity was 76.3%., Conclusions: The values of hs-CRP and ALB can be used as effective indexes in early diagnosis of intrauterine bacterial infection, and increase in 48-hour hs-CRP/ALB can improve the sensitivity of the diagnosis. Hs-CRP/ALB can be combined to guide rational use of antibiotics.