An all-inorganic lead-free metal halide double perovskite for the highly selective detection of norfloxacin in aqueous solution.

Lead-based perovskites are highly susceptible to environmental influences, and their application in analytical chemistry, especially in aqueous solution, has been reported rarely. All-inorganic lead-free metal halide perovskites have been considered as a substitute for lead-based perovskites. Herein, a Cs2RbTbCl6 perovskite microcrystal (PMCs), which emits strong yellow-green fluorescence with a maximum emission wavelength at 547 nm, was for the first time  synthesized and characterized. The Cs2RbTbCl6 PMCs could be well dispersed in N,N-dimethylacetamide (DMF), and its fluorescence could be significantly enhanced by the addition of norfloxacin (NOR) in the aqueous solution. We found that the Cs2RbTbCl6 PMCs can be used as fluorescent probes (excitation, 365 nm; emission, 547 nm) to selectively detect NOR in a concentration range from 10.0 to 200.0 µM with the limit of detection (LOD) being 0.04 µM. The Cs2RbTbCl6 PMCs could also be adsorbed on filter paper to fabricate as a fluorescent test paper for visual detection of NOR under 365-nm ultraviolet (UV) lamp irradiation. The proposed method has the potential to establish a new analytical method to visualize the detection of NOR in aqueous environments and also promotes the application of all-inorganic lead-free perovskites for analytical detection in aqueous environments.

1,3-Benzodioxole Derivatives Improve the Anti-Tumor Efficiency of Arsenicals.

Arsenicals have been widely used in the treatment of cancers such as leukemia and other tumors. However, their side effects limit their clinical application. Stiripentol, a second-line adjunctive treatment for epilepsy with a good safety profile, inhibits microsomal cytochrome-P450-family enzymes to extend the retention time of co-administration. Inspired by the metabolism of stiripentol, the 1,3-benzodioxole responsible for the inhibition and its metabolic derivatives were conjugated with arsenical precursors. The fabricated arsenicals were eliminated much slower in mice and maintained an efficient concentration in the blood for a longer time than that of the arsenical precursors. They also performed better in anti-proliferation by inhibiting the thioredoxin system to induce oxidative stress, and concomitantly to initiate apoptosis in vitro and in vivo. The fabricated arsenicals reversed the hemogram of tumor-bearing mice to normal and eliminated the tumor without causing damage to any organs, exhibiting a good design strategy and pre-clinical application for leukemia and other tumors.

Dipolar-Distribution Cavity γ-Fe2 O3 @C@α-MnO2 Nanospindle with Broadened Microwave Absorption Bandwidth by Chemically Etching.

Developing microwave absorption materials with ultrawide bandwidth and low density still remains a challenge, which restricts their actual application in electromagnetic signal anticontamination and defense stealth technology. Here a series of olive-like γ-Fe2 O3 @C core-shell spindles with different shell thickness and γ-Fe2 O3 @C@α-MnO2 spindles with different volumes of dipolar-distribution cavities were successfully prepared. Both series of absorbers exhibit excellent absorption properties. The γ-Fe2 O3 @C@α-MnO2 spindle with controllable cavity volume exhibits an effective absorption (<-10 dB) bandwidth as wide as 9.2 GHz due to the chemically dipolar etching of the core. Reflection loss of the γ-Fe2 O3 @C spindle reaches as high as -45 dB because of the optimized electromagnetic impedance balance between polymer shell and γ-Fe2 O3 core. Intrinsic ferromagnetism of the anisotropy spindle is confirmed by electron holography. Strong coupling of magnetic flux stray lines between spindles is directly imaged. This unique morphology and facile etching technique might facilitate the study of core-shell type microwave absorbers.

Fabrication of hierarchical TiO2 coated Co20Ni80 particles with tunable core sizes as high-performance wide-band microwave absorbers.

Multifunctional composite microspheres with a Co20Ni80 core and anatase TiO2 shells (Co20Ni80@TiO2) are synthesized by combining a solvothermal reaction and a calcination process, and include a series of microspheres with different core sizes (100 nm, 500 nm and 1 µm). The mechanism of self-assembly of the primary particles has been effective in both the fabrication of the core and the process of coating. The obtained core-shell particles possess superior monodispersity, size uniformity, and tailored core sizes, and are characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Furthermore, the electromagnetic shielding performance of the microspheres is investigated in terms of the theory of transmission lines. The Co20Ni80@TiO2 core-shell particle (CoNi@TiO2) with a well-defined core size of 500 nm demonstrates a remarkable wide-band electromagnetic shielding performance of up to 6.2 GHz (10.0-16.2 GHz, <-10 dB) within 2-18 GHz, which is due to the tunable multi-component hierarchical structure of the particles and contributes to the complex permittivity and permeability and the multiple scattering loss of the microwave. The Co20Ni80@TiO2 particle with a specific core size (500 nm) is a promising candidate for the wide-band electromagnetic shielding materials, gathering increasing interest from researchers.

Patients' poor communication with their doctors in the first visit of the gynecological endocrinology outpatient clinics.

OBJECTIVE: To investigate patients' communication with their gynecologists in the first visit of the gynecological endocrinology outpatient clinics. STUDY DESIGN: We developed a questionnaire to evaluate 379 women' expectations of their first visit, information-giving about illness, and understanding of the consultation they encountered from April to August 2010. Descriptive statistics and multiple linear regression analysis were used to analyze the data. RESULTS: Before the first visit, 55% (208/379) of participants hoped to get the doctors' special attention, and 60% (227/379) of patients expected a very satisfying consultation. During the consultation, only 34% (129/379) of patients provided their case history clearly according to physicians' inquiry, 21% (81/379) of patients understood the examination and 28% (105/379) of patients understood the therapeutic regime after doctors' explanation. Correlation analysis showed that sociodemographic characteristics such as young age (under 20 years old), low level of education (primary school or less), and lack of medical knowledge affected patients' information-giving about illness and understanding of their first visit (all ps < 0.05). CONCLUSIONS: Patients expected a patient-centered doctor-patient communication in gynecological endocrinology outpatient clinics. They could not communicate well with their doctors, which was affected by age, education, and medical background.

[Diagnosis boundary values of metabolic syndrome obesity index for children and adolescents].

OBJECTIVE: To determine the distribution characteristics of waist circumference (WC), waist height ratio (WHtR) of 6-18 years olds in Guangzhou, and to put forward the WC and WHtR appropriate boundary values for 6-18 years olds on the basis of cardiovascular disease (CVD) risk factor assessment. METHODS: We analyzed the height, weight, WC and its metabolic indication data (blood pressure, fasting blood glucose, and blood lipids) of 15 000 children in Guangzhou, aged 6-18, with the receiver-operating characteristic curve (ROC), and explored the best value point of WC and WHtR for the prediction of cardiovascular diseases. RESULTS: When the WC percent reached P85, and WHtR reached 0.48, the cardiovascular risk factors of fasting blood-glucose, blood pressure, and blood fat were significantly higher. CONCLUSION: The 85th percentile value of WC and 0.48 of WHtR are the appropriate boundary values in increasing the cardiovascular disease risk factors in Chinese children and teenagers. WC and WHtR as a relatively simple inspection method, can well predict cardiovascular diseases, and be used in the conventional measuring items among students.

Exosomes from Hypoxia-treated Mesenchymal Stem Cells: Promoting Neuroprotection in Ischemic Stroke Through miR-214-3p/PTEN Mechanism.

Stroke stands as the second leading cause of death globally, surpassed only by ischemic heart disease. It accounts for 9% of total worldwide deaths. Given the swiftly evolving landscape, medical professionals and researchers are devoting increased attention to identifying more effective and safer treatments. Recent years have witnessed a focus on exosomes derived from mesenchymal stem cells cultivated under hypoxic conditions, referred to as Hypo-Exo. These specialized exosomes contain an abundance of components that facilitate the restoration of ischemic tissue, surpassing the content found in normal exosomes. Despite advancements, the precise role of Hypo-Exo in cases of cerebral ischemia remains enigmatic. Therefore, this study was designed to shed light on the potential efficacy of Hypo-Exo in stroke treatment. Our investigations unveiled promising outcomes, as the administration of Hypo-Exo led to improved behavioral deficits and reduced infarct areas in mice affected by ischemic conditions. Notably, these positive effects were hindered when Hypo-Exo loaded with anti-miR-214-3p were introduced, implying that the neuroprotective attributes of Hypo-Exo are reliant on miR-214-3p. This conclusion was substantiated by the high levels of miR-214-3p detected within Hypo-Exo. Furthermore, our examination of the ischemic penumbra zone revealed a gradual and sustained escalation in PTEN expression, a phenomenon effectively countered by Hypo-Exo treatment. Collectively, our findings suggest the existence of a regulatory pathway centered on miR-214-3p within Hypo-Exo. This pathway exerts a downregulating influence on the PTEN/Akt signaling pathway, thereby contributing to the amelioration of neurological function subsequent to ischemia-reperfusion events.

A combination method to study the effects of petroleum on soil microbial activity.

TAM III multi-channel calorimetry was applied to study the effect of different concentrations petroleum on soil microbial activity and community. The microbial activities of the soil samples were recorded as power-time curves. The thermokinetic parameters such as microbial growth rate constant k, total heat evolution Q(T), metabolic enthalpy ∆H (met) and mass specific heat rate J(Q/S) were calculated. Results showed that petroleum had a certain extent effects to soil microorganisms. The results indicate that the soil microbial activity was promoted with a petroleum concentration lower than 0.52 % ± 0.24 %, but inhibited with further increase in petroleum.

[Accuracy evaluation of recording maxillomandibular relation with the mandibular kinesiography].

PURPOSE: To evaluate the accuracy of recording maxillomandibular position relationship with the mandibular kinesiography by surface electromyography analysis of the masticatory muscles and MRI of temporomandibular joint (TMJ). METHODS: Eight edentulous patients were selected randomly, and the maxillomandibular position relationship was determined by mandibular kinesiography and traditional method respectively. Then the corresponding bite plates were made to wear. Surface electromyography test of left and right anterior temporal and masseter muscle and magnetic resonance scan of the temporomandibular joint were performed on closed mouth position to record peak potentials, calculate asymmetric indexes, analyze the position relationship between the joint disc and the condyle, measure TMJ joint space. SPSS 18.0 software package was used for data analysis. RESULTS: There was no significant difference in the amplitude of the anterior temporal or masseter muscle, the asymmetry index of total, asymmetry index of masseter, asymmetry index of temporalis, the anterior, upper and posterior spaces of TMJ between the mandibular kinesiography group and the traditional group (P＞0.05). The temporomandibular articular disc process relationship of the two groups were conformed to the normal physiological position relationship. CONCLUSIONS: Mandibular kinesiography could accurately record the maxillomandibular position relationship in patients with edentulous jaws.

Impacts of top predators and humans on the mammal communities of recovering temperate forest regions.

Top predators are important drivers in shaping ecological community structure via top-down effects. However, the ecological consequences and mechanisms of top predator loss under accelerated human impacts have rarely been quantitatively assessed due to the limited availability of long-term community data. With increases in top predator populations in northern China over the past two decades, forests with varying densities of top predators and humans provide an opportunity to study their ecological effects on mammal communities. We hypothesized a priori of conceptual models and tested these using structural equation models (SEMs) with multi-year camera trap data, aiming to reveal the underlying independent ecological effects of top predators (tigers, bears, and leopards) and humans on mammal communities. We used random forest models and correlations among species pairs to validate results. We found that top predator reduction could be related to augmented populations of large ungulates ("large ungulate release") and mesopredators ("mesopredator release"), consistent with observations of mammal communities in other ecosystems. Additionally, top predator reduction could be related to reduced small mammal abundance. Hierarchical SEMs identified three bottom-up pathways from forest quality to human activities, large ungulates, and some small mammals, and five top-down pathways from human activities and top predators to some small mammals, large ungulates, and mesopredators. Furthermore, our results suggest that humans showed predominant top-down effects on multiple functional groups, partially replacing the role of top predators, rather than be mediated by them; effects of humans and top predators appeared largely independent. Effects of humans on top predators were non-significant. This study provides novel insights into the effects of top predators and humans as super-predators on mammal communities in forest ecosystems and presents cues of bottom-up effects that can be translated into actionable management plans for improving forest quality, thereby supporting top predator recovery and work/life activities of local people.

Wavelet methods reveal big cat activity patterns and synchrony of activity with preys.

Appropriate temporal and spatial scales are important prerequisites for obtaining reliable results in studies of wildlife activity patterns and interspecific interactions. The spread of camera-trap technology has increased interest in and feasibility of studying the activity patterns and interspecific interactions of wildlife. However, such studies are often conducted at arbitrary spatial and temporal scales, and the methods used impose scale on the study rather than determining how activity and species interactions change with spatial scale. In this study, we used a wavelet-based approach to determine the temporal and spatial scales for activity patterns and interspecific interactions on Amur leopard and their ungulate prey species that were recorded using camera traps in the main Amur leopard occurrence region in northeast China. Wavelets identified that Amur leopards were more active in spring and fall than summer, and fluctuated with periodicities of 9 and 17 days, respectively. Synchronous relationships between leopards and their prey commonly occurred in spring and fall, with a periodicity of about 20 days, indicating the appropriate seasons and temporal scales for interspecific interaction research. The influence of human activities on the activity patterns of Amur leopard or prey species often occurred over longer time periods (60-64 days). Two-dimensional wavelet analyses showed that interactions between leopard and prey were more significant at spatial scales of 1 km2 . Overall, our study provides a feasible approach to studying the temporal and spatial scales for wildlife activity patterns and interspecific interaction research using camera trap data.

Multifunctional Probes with High Utilization Rates: Self-Assembled Merocyanine Nanoparticles in Water as Acid-Base Indicators and Mitochondrion-Targeting Chemotherapeutic Agents.

Multifunctional probes with high utilization rates have great value in practical applications in various fields such as cancer diagnosis and therapy. Here we have synthesized two organic molecules based on merocyanine. They can self-assemble in water to form ∼1.5 nm nanoparticles. Both of them have good application potential in fluorescent anticounterfeit printing ink and pH detection. More importantly, they have excellent mitochondrial targeting ability, intracellular red light and near-infrared dual-channel imaging ability, strong antiphotobleaching ability, and in vivo and in vitro near-infrared imaging capabilities, showing superior chemotherapy capabilities and biocompatibility in the 4T1 tumor-bearing mouse model.

[Fracture resistance of endodontically treated maxillary premolars restored with different CAD/CAM all-ceramic restorations].

PURPOSE: This study was to evaluate the fracture resistance of endodontically treated maxillary premolars restored with different CAD/CAM all-ceramic restorations in vitro. METHODS: Mesio-occluso-function tip(MOF) cavities were prepared in 21 extracted human maxillary premolars due to endodontic treatment. The teeth were divided into 3 groups. G1:conventional composite resin; G2: cavities；G3: conventional composite resin with a horizontal glass fiber post inserted palatal walls. Restorations were fabricated from a pressable lithium disilicate glass-ceramic and adhesively cemented (Rely X U200). Then, the specimens were subjected to a compressive load at a crosshead speed of 0.5 mm/min until fracture. The fractured specimens were analyzed to determine the fracture pattern using a stereomicroscope. SPSS 15.0 software package was used to analyse the data. RESULTS: G3（1570.7±108.7） had higher failure load than G1(1214.6±95.8) and G2(1285.9±87.6)(P<0.05). G1 was similar to G2.The crown was lost in G1 and G2. There was a fracture of the crown and tooth in G3. CONCLUSIONS: CAD/CAM all-ceramic crown with fiberglass posts might be an effective method for restoration of endodontically treated premolars with MOF cavity defect.

Effects of Carbon Arc Lamp Irradiation on Wound Healing in a Rat Cutaneous Full-Thickness Wound Model.

Objective: The objective of the present study was to investigate the application of a carbon arc lamp on wound healing in a rat cutaneous full-thickness wound model. Background data: In clinical practice, wound healing has been promoted by irradiation with a carbon arc lamp. However, the corresponding mechanism has not been clearly defined. Methods: A cutaneous full-thickness wound on the back of rats was irradiated using a carbon arc lamp at a wavelength peak range of 620-740 nm with 54 J/cm2. Injured sham-irradiated control rats were used as the control. The rats were euthanized after 7, 14, and 21 days, while wound reepithelialization and healing quality were examined by histological analyses with comparison between groups. Cell proliferation was observed by 5-bromo-2'-deoxyuridine (BrdU) immunohistochemical staining. Results: Irradiation by the carbon arc lamp significantly accelerated wound healing. The wound-healing rate in the treated group at day 21 was 98.42% ± 0.56%, compared with 93.58% ± 1.26% in the control group (p < 0.05). Significant increases in the length of epithelial edges, collagen content, and microvessel density were observed in the wound sites in the treated group at days 7, 14, and 21 (p < 0.05). Moreover, the number of BrdU-labeled cells increased in the wound edge at days 7 and 14 due to irradiation (p < 0.05). Conclusions: The results demonstrated that the carbon arc lamp can promote wound healing together with improvement in its quality by stimulating cell proliferation.

Effects of storage culture media, temperature and duration on human adipose­derived stem cell viability for clinical use.

Adipose­derived stem cells (ADSCs) are mesenchymal stem cells that are often used in regenerative medicine. Maintaining ADSC viability is important, as this optimizes the curative effects of cell therapy. However, the optimal conditions for cell viability preservation remain unknown. The present study aimed to acquire a better protocol for ADSC storage by comparing the effects of various solutions and temperatures for ADSC preservation, in order to suggest the most effective methods of short­term ADSC preservation for clinical use. ADSCs from passage 2 were suspended in solutions comprising 0.9% NaCl, 10% human serum (HS) or 10% platelet­rich plasma (PRP). Suspended cells were maintained at 4˚C or room temperature (~26˚C) for 2, 4 and 6 h. The differentiation capacity, apoptosis and proliferation of ADSCs were determined by oil red O/alizarin red S staining, flow cytometry, and a cell counting kit­8 cell proliferation assay, respectively. In addition, reverse transcription­quantitative polymerase chain reaction and western blot analysis was performed. The results revealed that proliferation of ADSCs decreased with time. The optimal time for ADSC use was ~2 h, and 4 h was determined to be the latest time that ADSCs should be used. The 10% HS group had the highest survival rate, followed by the 10% PRP group; these two groups had higher survival rates than the 0.9% NaCl group (P<0.05). HS and PRP at 4˚C enhanced the ADSC proliferation rate (P<0.05), although the difference between these two groups was insignificant (P>0.05). In conclusion, the optimal time to use ADSCs was <2 h, and should not exceed 4 h. It was recommended that, for the transportation and short­term storage of ADSCs during clinical use, they should be stored with 10% HS at 4˚C to maintain ADSC viability. In addition, this was a cost­effective and safe method.

Studies of the Anti-amnesic Effects and Mechanisms of Single and Combined Use of Donepezil and Ginkgo Ketoester Tablet on Scopolamine-Induced Memory Impairment in Mice.

Ginkgo ketoester tablets (GT) and donepezil were a clinically used combination for the treatment of Alzheimer's disease (AD). The aim of the study was undertaken to investigate the antiamnesic effects of the two drugs alone and in combination through in vivo models of the Morris water maze along with in vitro antioxidants, acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). The potential mechanisms were speculated by the activities of acetylcholine (ACh), AChE, superoxide dismutase (SOD), and malondialdehyde (MDA) and the protein expression of brain-derived neurotrophic factor (BDNF) and tyrosine protein kinase B (TrkB). The combination group showed a concentration-dependent inhibition of cholinesterase and antioxidation. As far as its mechanism was concerned, the combination of two drugs exerted excellent effects on oxidative stress, cholinergic pathway damage, and inactivation of the BDNF-TrkB signaling pathway. Additionally, to elucidate the binding mechanism of GT active ingredients into the structure of AChE, the results of molecular docking studies indicated that hydrogen and/or hydrophobic bonds might play an important role in their binding process. Thus, the combination of drugs could treat AD perfectly and further verify the scientific rationality of clinical medication.

[Xianling Gubao Capsule improves semen quality].

OBJECTIVE: To observe the effect of the compound Chinese traditional drug Xianling Gubao Capsule on the semen quality of infertile males. METHODS: We treated 66 infertile men with Xianling Gubao Capsule for 24 months, and analyzed the semen quality and sperm morphology before and after the treatment. RESULTS: Two months after the medication, sperm concentration was increased by a small margin, but no statistically significant changes were observed in sperm vitality and motility (P > 0.05), the rate of morphologically normal sperm was significantly raised from 25.8% before treatment to 57.6% (P < 0.05) in those with the normal rate > or = 15%, but decreased from 53.0% to 25.8% (P < 0.05) in those with the normal rate < 9%. Among the 7 cases of oligospermia, the rate of morphologically normal sperm was elevated to an average of 10.9% after the 4-month medication, significantly different from the baseline rate of 5.8% (P < 0.05). Five spontaneous pregnancies and 1 successful IVF-ICSI were achieved during the treatment. CONCLUSION: Xianling Gubao Capsule can improve semen quality and significantly increase the percentage of morphologically normal sperm.

Effects of Carbon Arc Lamp Irradiation on Wound Healing in a Rat Cutaneous Full-Thickness Wound Model.

OBJECTIVE: The objective of the present study was to investigate the application of a carbon arc lamp on wound healing in a rat cutaneous full-thickness wound model. BACKGROUND DATA: In clinical practice, wound healing has been promoted by irradiation with a carbon arc lamp. However, the corresponding mechanism has not been clearly defined. METHODS: A cutaneous full-thickness wound on the back of rats was irradiated using a carbon arc lamp at a wavelength peak range of 620-740 nm with 54 J/cm2. Injured sham-irradiated control rats were used as the control. The rats were euthanized after 7, 14, and 21 days, while wound reepithelialization and healing quality were examined by histological analyses with comparison between groups. Cell proliferation was observed by 5-bromo-2'-deoxyuridine (BrdU) immunohistochemical staining. RESULTS: Irradiation by the carbon arc lamp significantly accelerated wound healing. The wound-healing rate in the treated group at day 21 was 98.42% ± 0.56%, compared with 93.58% ± 1.26% in the control group (p < 0.05). Significant increases in the length of epithelial edges, collagen content, and microvessel density were observed in the wound sites in the treated group at days 7, 14, and 21 (p < 0.05). Moreover, the number of BrdU-labeled cells increased in the wound edge at days 7 and 14 due to irradiation (p < 0.05). CONCLUSIONS: The results demonstrated that the carbon arc lamp can promote wound healing together with improvement in its quality by stimulating cell proliferation.

[Effect of ball attachments with different materials on retention of mandibular implant supported overdenture].

PURPOSE: To investigate the effect of ball attachments with different materials on retention of mandibular implant supported overdenture. METHODS: The experimental groups were divided into group A (titanium ball / titanium cap group) and group B (titanium ball / golden cap group), each group had 3 samples. A standard mandibular edentulous model was made, and the implants (4.8*10 RN SP) were embedded in the bilateral canine region. Mandibular complete dentures were made routinely and the attachments were attached. Five thousand times of insertion-separation cycles were carried out. After 200 times of cycles, the retention force was tested. The difference between 2 groups was compared by using SPSS 13.0 software package. The change of positive structure surface morphology was observed under scanning electron microscope at the beginning and the end of the experiment. RESULTS: The retention force of group A decreased from （27.00±0.16） N to （4.18±0.03） N, and the retention force of group B decreased from （21.58±0.06） N to （19.15±0.06）N. Decay of retention of group A was significantly greater than that of group B. At the end of the experiment, the globular structure of group A was severely broken, while a smooth and clear spherical structure was displayed in group B. CONCLUSIONS: The retention of mandibular implant supported overdenture decreases with the increase of insertion-separation times. The decay of retention force is related to destruction of positive structure surface. The fatigue resistance of the precious metal material is better.

A novel gene mutation of Runx2 in cleidocranial dysplasia.

Haploinsufficiency of the runt-related transcription factor 2 (Runx2) gene is widely known to be responsible for cleidocranial dysplasia (CCD). To date, more than 190 mutations in Runx2 gene have been reported to be related to CCD. In this study, a novel mutation of Runx2 gene was observed in a female with CCD. Genomic DNA was extracted from peripheral venous blood of the proband and eleven members of her family. Genetic testing on these twelve people identified a novel missense mutation (c.895 T>C, Y299H) in exon 5 of the RUNX2 gene in the proband. This mutation results in an amino acid change at codon 895 (P.Tyr 299 His.) from a tryptophan codon (TAT) to a histidine codon (CAT). Our finding may further extend the known mutation spectrum of the RUNX2 gene, and facilitate prenatal genetic diagnosis of CCD in the future.