Thermally Enhanced and Long Lifetime Red TADF Carbon Dots via Multi-Confinement and Phosphorescence Assisted Energy Transfer.

Thermally activated delayed fluorescence (TADF) materials, which can harvest both singlet and triplet excitons for high-efficiency emission, have attracted widespread concern for their enormous applications. Nevertheless, luminescence thermal quenching severely limits the efficiency and operating stability in TADF materials and devices at high temperature. Herein, a surface engineering strategy is adopted to obtain unique carbon dots (CDs)-based thermally enhanced TADF materials with ≈250% enhancement from 273 to 343 K via incorporating seed CDs into ionic crystal network. The rigid crystal network can simultaneously boost reverse intersystem crossing process via enhancing spin-orbit coupling between singlet and triplet states and suppressing non-radiative transition rate, contributing to the thermally enhanced TADF character. Benefiting from efficient energy transfer from triplet states of phosphorescence center to singlet states of CDs, TADF emission at ≈600 nm in CDs displays a long lifetime up to 109.6 ms, outperforming other red organic TADF materials. Thanks to variable decay rates of the delayed emission centers, time and temperature-dependent delayed emission color has been first realized in CDs-based delayed emission materials. The CDs with thermally enhanced and time-/temperature-dependent emission in one material system can offer new opportunities in information protection and processing.

Global Spread Dynamics and Intrinsic Evolutionary Dynamics of Apple Chlorotic Leaf Spot Virus Whole-Genome Sequences over the Last 30 Years.

Apple chlorotic leaf spot virus (ACLSV; genus Trichovirus) is an economically important virus. Approximately 101 ACLSV whole-genome sequences were obtained from NCBI and used to explore the evolutionary dynamics of ACLSV. The time to the most recent common ancestor of ACLSV based on BEAST analysis appeared on an apple host from Canada in 1918 and then spread around the world in three ways concurrent with host spread. The maximum clade credibility tree of ACLSV shows that the mean evolution rate was 4.92 × 10-4 substitutions per site per year (subs/site/year), and we found that, during host evolution, the rate of evolution was mostly 2.31 × 10-4 to 2.72 × 10-4 subs/site/year. The rate of geographic evolution was 5.51 × 10-4 to 6.17 × 10-4 subs/site/year. To further explore the intrinsic changes in ACLSV during the process of geographic and host spread, we explored the secondary structural changes of the ACLSV coat protein (CP), which were mainly concentrated in four regions-20 to 40, 70 to 90, 120 to 140, and 180 to 193-which are related to the presence or absence and change in length of the ß-turn, ß strand, coil, and α helix, respectively. We then explored the codon usage preference within the CP across the migration pathways of ACLSV. These comprehensive analyses not only reveal the changes in ACLSV in the last 30 years but also further elucidate the intrinsic evolutionary dynamics of ACLSV. This is also the first report on the intrinsic evolutionary dynamics of ACLSV.

1H-MR spectroscopy in grading of cerebral glioma: A new view point, MRS image quality assessment.

BACKGROUND: Noninvasive preoperative prediction of histological grading is essential for clinical management of cerebral glioma. PURPOSE: This study aimed to investigate the association between the image quality assessment of 1H magnetic resonance spectroscopy and accurate grading of glioma. MATERIALS AND METHODS: 98 glioma patients confirmed by pathology were retrospectively recruited in this single-center study. All patients underwent 1H-MRS examination at 3.0T before surgery. According to WHO standards, all cases were divided into two groups: low-grade glioma (grade I and II, 48 cases) and high-grade glioma (grades III and IV, 50 cases). The metabolite ratios in both grades were calculated before and after image quality assessment. The area under the receiver operating characteristic (ROC) curve was used to evaluate the capacity of each ratio in glioma grading. RESULTS: The Cho/Cr, Cho/NAA and NAA/Cr metabolite ratios had certain differences in each glioma group before and after MRS image quality assessment. In the low-grade glioma group, there was a dramatic difference in the Cho/Cr ratio before and after image quality assessment (p = 0.011). After MRS image quality assessment, the accuracy of glioma grading was significantly improved. The Cho/Cr ratio with 83.3% sensitivity and 93.7% specificity is the best index of glioma grading, with the optimal cutoff value of the Cho/Cr ratio being 3.72. CONCLUSION: The image quality of MRS does affect the metabolite ratios and the results of glioma grading. MRS image quality assessment can observably improve the accuracy rate of glioma grading. The Cho/Cr ratio has the best diagnostic performance in differentiating high-grade from low-grade glioma.

Upside-down InAs/InAs1-xSbx type-II superlattice-based nBn mid-infrared photodetectors with an AlGaAsSb quaternary alloy barrier.

Ga-free InAs/InAsSb type-II superlattices (T2SLs) are emerging as candidate materials for high temperature operation of mid-infrared photodetectors, which are critical for infrared technology with an aim to provide low-cost and compact detection systems. In this work, by utilizing upside-down device structure, a closely lattice-matched Al0.83Ga0.17AsSb quaternary alloy as electron barrier was pre-grown before the growth of InAs/InAsSb T2SLs absorber in a nBn device. Based on this design, we have demonstrated 5-µm cut-off mid-wavelength infrared (MWIR) photodetectors that exhibited a dark current density of 1.55 × 10-4 A/cm2 at an operation bias 400mV at 150K. A saturated quantum efficiency at ∼4.0 µm reaches 37.5% with a 2 µm absorber and the peak responsivity reaches 1.2 A/W, which yields a peak specific detectivity as high as ∼1.82 × 1011 cm·H z1/2/W at a forward bias of 400mV.

Differences of dynamic connectivity of motor function network between meningioma and low-grade glioma based on wavelet transform / 中国医学影像技术

Objective: To observe the differences of dynamic connectivity in motor function networks between meningioma and low-grade glioma. Methods: Totally 14 patients with meningioma (meningioma group), 14 patients with low grade gliomas (gliomas group) and 14 healthy controls (control group) were enrolled. The wavelet transform coherence (WTC) was used to analyze the dynamic connectivity in motor function networks of 3 groups. Results: The motor function networks nodes were determined by hands movement task stimulus and the generalized linear model analysis, which located at the left and right side of the primary motor cortex (LPMC and RPMC) and the supplementary motor area (SMA). The values of WTC in LPMC-SMA, RPMC-SMA and LPMC-RPMC in meningioma group and gliomas group were lower than those in control group, and in gliomas group were lower than those in meningioma group (all P<0.05). Conclusion: Low frequency fluctuation alteration of connectivity in motor function networks in patients with meningioma and low grade gliomas can be sensitively detected using WTC.

Enhancement by Metallic Tube Filling of the Mechanical Properties of Electromagnetic Wave Absorbent Polymethacrylimide Foam.

By the addition of a carbon-based electromagnetic absorbing agent during the foaming process, a novel electromagnetic absorbent polymethacrylimide (PMI) foam was obtained. The proposed foam exhibits excellent electromagnetic wave-absorbing properties, with absorptivity exceeding 85% at a large frequency range of 4.9⁻18 GHz. However, its poor mechanical properties would limit its application in load-carrying structures. In the present study, a novel enhancement approach is proposed by inserting metallic tubes into pre-perforated holes of PMI foam blocks. The mechanical properties of the tube-enhanced PMI foams were studied experimentally under compressive loading conditions. The elastic modulus, compressive strength, energy absorption per unit volume, and energy absorption per unit mass were increased by 127.9%, 133.8%, 54.2%, and 46.4%, respectively, by the metallic tube filling, and the density increased only by 5.3%. The failure mechanism of the foams was also explored. We found that the weaker interfaces between the foam and the electromagnetic absorbing agent induced crack initiation and subsequent collapses, which destroyed the structural integrity. The excellent mechanical and electromagnetic absorbing properties make the novel structure much more competitive in electromagnetic wave stealth applications, while acting simultaneously as load-carrying structures.

Exercise interventions on patients with end-stage renal disease: a systematic review.

OBJECTIVE:: This study aimed to conduct an up-to-date systematic review of the literature to evaluate the effects of exercise on fatigue, anxiety, depression, physical activity, and quality of life (QOL) in patients with end-stage renal disease. DATA SOURCES:: We searched PubMed (October 2018), Embase (from 1966 to October 2018), Web of Science (from 1900 to October 2018), The Cochrane Library (October 2018), and references of papers. METHODS:: This study includes randomized controlled trials that analyzed the combined effects of exercise intervention on patients with end-stage renal disease. Two reviewers independently screened the retrieved records, extracted data, and assessed the risk of bias for inclusion in the study. The effects of exercise intervention were conducted in the meta-analysis using RevMan 5.3 software. RESULTS:: A total of 614 participants were included in 13 randomized controlled studies. The study revealed that exercise can improve fatigue, anxiety, depression, physical activity, and QOL. The effect value results were as follows: (1) fatigue, -0.97 (95% confidence interval (CI) -1.32 to -0.62, P < 0.00001); (2) anxiety, -0.78 (95% CI -1.17 to -0.39, P < 0.0001); (3) depression, -0.85 (95% CI -1.13 to -0.56, P < 0.00001) (4) physical activity, 38.15 (95% CI 21.20 to 55.10, P < 0.0001); (5) QOL, the physical component of the 36-item Short-Form Health Survey (SF-36), 4.73 (95% CI 1.92 to 7.54, P = 0.0010); and (6) the mental component of the SF-36, 3.42 (95% CI 0.27 to 6.56, P = 0.03). CONCLUSION:: Exercise intervention is more effective in fatigue, anxiety, depression, physical activity, and QOL. However, large-scale randomized controlled trials are needed to confirm the appropriate types of exercise and optimal time for patients with end-stage renal disease.

Research progress on neural mechanism of peripheral inflammation in Parkinson's disease / 生理学报

Parkinson's disease (PD) is the second most common neurodegenerative disease, characterized by loss of dopaminergic (DA) neurons in the dense part of the substantia nigra (SNpc). Postmortem analysis of PD patients and experimental animal studies found that microglial cell activation and increased levels of pro-inflammatory factors were common features of PD brain tissue. At the same time, the invasion and accumulation of peripheric immune cells were detected in the brain of PD patients. In this paper, peripheral inflammation across the blood-brain barrier (BBB), the misfolded α-synuclein (α-syn)-induced microglial cell activation and intracerebral inflammation in PD are summarized, providing potential therapeutic measures for delaying the onset of PD.

Super-Resolution Track-Density Imaging Reveals Fine Anatomical Features in Tree Shrew Primary Visual Cortex and Hippocampus / 神经科学通报·英文版

Diffusion-weighted magnetic resonance imaging (dMRI) is widely used to study white and gray matter (GM) micro-organization and structural connectivity in the brain. Super-resolution track-density imaging (TDI) is an image reconstruction method for dMRI data, which is capable of providing spatial resolution beyond the acquired data, as well as novel and meaningful anatomical contrast that cannot be obtained with conventional reconstruction methods. TDI has been used to reveal anatomical features in human and animal brains. In this study, we used short track TDI (stTDI), a variation of TDI with enhanced contrast for GM structures, to reconstruct direction-encoded color maps of fixed tree shrew brain. The results were compared with those obtained with the traditional diffusion tensor imaging (DTI) method. We demonstrated that fine microstructures in the tree shrew brain, such as Baillarger bands in the primary visual cortex and the longitudinal component of the mossy fibers within the hippocampal CA3 subfield, were observable with stTDI, but not with DTI reconstructions from the same dMRI data. The possible mechanisms underlying the enhanced GM contrast are discussed.

Acclimatization to middle altitude hypoxia protects against developmental and cognitive deficits caused by acute fetal hypoxia in mice / 生理学报

Acute fetal hypoxia (AFH) can elicit postnatal motor deficits and cognitive impairments. To test whether lifelong acclimatization to middle altitude (MA) hypoxia has protective effects on the impairments caused by AFH, ICR mice bred at 1 900 m altitude for 6-7 generations were evaluated under AFH. On gestation day 9 (GD 9), 13 (GD 13) or 17 (GD 17), pregnant mice received a single exposure to acute hypoxia (7% O, 6 h). Physiological and neurodevelopmental behaviors, motor function (open field), spatial learning and memory (Morris water maze), and anxiety level (elevated plus maze) were examined in the offspring from neonate to adulthood. In the neonatal age, among all the physiological and behavioral landmarks, almost no differences were found in the hypoxia groups. In the juvenile period, no obvious impairments of motor function and anxiety level were found in the hypoxia groups. In the adult period, no obvious impairment of motor function was found in hypoxia groups; Interestingly, AFH groups' offspring showed normal or enhanced long-term spatial memory ability after AFH. These data suggest that AFH cause little abnormalities in the offspring of MA-adapted mice. To further investigate the underlying mechanisms, the neuronal numbers in behavior-related brain areas (accumbens nucleus, basal amygdala and hippocampus) were counted, and the physiological parameters of the blood were measured. The morphological data showed that no obvious neuronal necrosis was found in all hypoxia groups. In addition, blood tests showed that red blood corpuscle count, hemoglobin concentration and hematocrit levels in mice raised at MA were markedly higher in both males and females, compared with controls raised at the sea level. These data suggest that lifelong acclimatization to MA hypoxia has protective effects against development delay, motor deficits and spatial learning and memory impairments induced by AFH, and the protective effects may be due to higher hemoglobin concentration and hematocrit levels in the blood. The findings may provide a better understanding of fetal hypoxia and potential intervention treatments.

Methylation of GSTP1 promoter region in hepatocellular injury induced by isoniazid / 国际药学研究杂志

Objective To investigate the relationship between methylation of CpG island in glutathione S-transferase P1(GSTP1) promoter region and injury induced by isoniazid in HL-7702 cells.Methods HL-7702 cells were divided into the control group and three isoniazid groups(200,400,800 mg/L).Colorimetric method was used to detect the activity level of lactate dehydrogenase in the medium of HL-7702 cells;the mRNA expression of GSTP1,DNA methyltransferases 1(DNMT1),DNMT3a and DNMT3b were de?tected by real-time fluorescence quantitative PCR;the protein expression levels of DNMT1,DNMT3a and DNMT3b were detected by enzyme-linked immunosorbent assay;the methylation of the CpG island in the GSTP1 promoter region was determined by the bisulfite sequencing PCR.Results The activity level of lactate dehydrogenase in supernatants of the HL-7702 cells in isoniazid group(400, 800 mg/L)was higher than that in the control group(P<0.01).Compared with the control group,the mRNA expression of DNMT 1、3a、3b and GSTP1 were elevated in 400 and 800 mg/L isoniazid groups(P<0.05,P<0.01).The proteins expression of DNMT1 and 3a in the 400 and 800 mg/L isoniazid groups were higher than that in the control group(P<0.05,P<0.01),and the protein expression of DNMT 3b in the 800 mg/L isoniazid groups were higher than that in the control group(P<0.01).The methylation level of CpG is?land in GSTP1 promoter region of three isoniazid groups were decreased.Conclusion The CpG island in the promoter of GSTP1 has hypomethylation in hepatocyte cells damaged by isoniazid.

Relationship between long non-coding RNA metastasis associated lung adenocarcinoma transcript 1 and IL-6/STAT3 signaling pathway in isoniazid-induced rats liver injury / 国际药学研究杂志

Objective To explore the link between the expression of long non-coding RNA(lncRNA)metastasis associated lung adenocarcinoma transcript 1(MALAT1)and IL-6/signal trans ducers and activators of transcription 3(STAT3)signaling pathway in isoniazid induced rats liver injury. Methods Fifty-six specific pathogen-free(SPF)SD rats were randomly divided into experimen?tal group(48 rats)and control group(8 rats),each with half females and half males. The rats in experimental group were given isonia?zid of 63 mg/(kg·d)for 3,7,10,14,21 and 28 d,with 8 rats at the same time point of each day. The rats in control group were giv?en distilled water by intragastric administration. Serum levels of ALT and AST were measured by automatic biochemical analyzer;SYBR green real-time polymerase chain reaction was used to test the expression level of lncRNA MALAT1 and IL-6/STAT3 mRNA in the liver. Results Liver tissue injury occurred after 7 days and worsened with the extention of administration time. Compared with the rats in the control group,the expression level of lncRNA MALAT1 and IL-6/STAT3 mRNA as well as ALT and AST showed a trend of increase(P<0.01). The expression of ALT,AST and lncRNA MALAT1 declined at different degrees on 28(P<0.05). LncRNA MALAT1 and IL-6/STAT3 mRNA expression levels were positively correlated(P<0.01). LncRNA MALAT1 and IL-6/STAT3 mRNA expression levels had a positive correlation with the contents of ALT and AST(P<0.01). Conclusion The expression level of lncRNA MALAT1 in isoniazid induced liver injury rat models showed an abnormal rising trend,and the positive detection time preceded that of ALT and AST. The mechanism may be related to the activation of IL-6/STAT3 signaling pathway.

The value of T2 signal intensity in DTI to differentiate between brain tumor infiltration and pure vasogenic edema / 实用放射学杂志

Objective To explore the added value of T2-signal intensity (T2-SI) in discriminating tumor-infiltration from pure vasogenic edema with diffusion tensor imaging (DTI).Methods 55 patients with brain tumors [28 with high-grade glioma (HGG),13 with meningioma,and 14 with metastases] and concurrent peritumoral edema were scanned with DTI.The mean fractional anisotropy (FA),mean diffusivity (MD),longitudinal diffusivity (λ//) and radial diffusivity (λ⊥) in peritumoral edema of different tumors were measured and compared with each other.Results Only the mean FA showed significant difference between edema of HGG and meningioma (P＜0.05).When standardized T2-SI was used as the covariant,FA and λ⊥ showed significant differences among the tumor groups.The adjusted FA in edema of HGG was significantly lower than that of metastases (P＜0.05) and meningioma (P＜ 0.001).The adjusted λ⊥ in edema of HGG was significantly higher than that of meningioma (P＜0.05).Conclusion By controlling the effect of T2-SI,the value of DTI in distinguishing tumor-infiltration from pure vasogenic edema could be improved.

Research on promotory effect of traditional Chinese medicine on fracture healing in cell and molecular level / 中国骨伤

Traditional Chinese medicine is widely used in the treatment of fractures, osteoporosis, other bone related diseases for thousands of years. There are many animal experiments and clinical trials demonstrating that the traditional Chinese medicine such as epimedium, Drynaria and other traditional Chinese medicine can stimulate bone regeneration and inhibit bone resorption, accelerating the fracture healing. In recent years many cell experiments have shown that these herbal ingredients up-regulated the expression of intracellular osteogenic transcription factors and osteogenic related genes, and then induced osteoblastic differentiation and stimulated the proliferation of osteoblasts, bone nodule formation and matrix mineralization. Meanwhile these herbal ingredients up-regulated the expression of intracellular osteoclastic transcription factors and osteoclast related genes, inhibited osteoclast differentiation and bone resorption of osteoclasts. In addition, intracellular signaling pathways regulated these herbal ingredients by might be involved in the above effects. We can have a conclusion that the genes expression regulated by transcription factors in pre-osteoblast and pre-osteoclast and these signaling pathways are the major molecular mechanisms and research hotspots of traditional Chinese medicine in promoting fracture healing. Based on these molecular mechanisms to review, this review provides not only the foundation for the study of traditional Chinese medicine in promoting fracture healing, but also the basis for clinical treatment of fracture.

Optimal Factors of Diffusion Tensor Imaging Predicting Corticospinal Tract Injury in Patients with Brain Tumors

OBJECTIVE: To identify the optimal factors in diffusion tensor imaging for predicting corticospinal tract (CST) injury caused by brain tumors. MATERIALS AND METHODS: This prospective study included 33 patients with motor weakness and 64 patients with normal motor function. The movement of the CST, minimum distance between the CST and the tumor, and relative fractional anisotropy (rFA) of the CST on diffusion tensor imaging, were compared between patients with motor weakness and normal function. Logistic regression analysis was used to obtain the optimal factor predicting motor weakness. RESULTS: In patients with motor weakness, the displacement (8.44 ± 6.64 mm) of the CST (p = 0.009), minimum distance (3.98 ± 7.49 mm) between the CST and tumor (p < 0.001), and rFA (0.83 ± 0.11) of the CST (p < 0.001) were significantly different from those of the normal group (4.64 ± 6.65 mm, 14.87 ± 12.04 mm, and 0.98 ± 0.05, respectively) (p = 0.009, p < 0.001, and p < 0.001). The frequencies of patients with the CST passing through the tumor (6%, p = 0.002), CST close to the tumor (23%, p < 0.001), CST close to a malignant tumor (high grade glioma, metastasis, or lymphoma) (19%, p < 0.001), and CST passing through infiltrating edema (19%, p < 0.001) in the motor weakness group, were significantly different from those of the patients with normal motor function (0, 8, 1, and 10%, respectively). Logistic regression analysis showed that decreased rFA and CST close to a malignant tumor were effective variables related to motor weakness. CONCLUSION: Decreased fractional anisotropy, combined with closeness of a malignant tumor to the CST, is the optimal factor in predicting CST injury caused by a brain tumor.

Application study of the motor function area in patients with meningioma by functional magnetic resonance imaging / 实用放射学杂志

Objective To evaluate the functional features of motor function area in patients with meningioma by blood oxygenation level dependent functional magnetic resonance imaging (BOLD-fMRI).Methods fMRI were obtained from 10 patients who suffered from meningioma which was adjacent to the motor function cortex.Probabilistic independent component analysis method was used for data analysis.Preoperative and postoperative line Karnofsky Performance Scale (KPS)score was used to assess the patient’s condition.Re-sults Contralateral primary motor cortex and the supplementary motor cortex motor functions were observed in all the activation clusters,in which one side activation area compared with the contralateral activation zone was symmetrical in 6 cases,and significant shift in 4 cases.In 4 patients with the movement function activated,tumor extrusion function shift forward or backwardwith tensile deforma-tion were found.Conclusion BOLD-fMRI imaging technology can effectively locate motor functional area for patients with meningi-oma,which can provide preoperative surgical planning.

Effect of repetitive hypoxia on MMP-2/9 expression and activation in murine brain / 中国应用生理学杂志

<p><b>AIM</b>To explore the changes of MMP-2/9 protein expression and excitation in brain of repetitive hypoxic mice.</p><p><b>METHODS</b>The biochemistry techniques of SDS-PAGE, Western bolt and Gel Goc Image Analysis System were applied to determine the level of MMP-2 and MMP-9 expression and activation in cortex and hippocampus of mice. The animals were randomly divided into 5 groups: the normal control group (H0), acute hypoxic (H1, hypoxic exposure once), repetitive hypoxic groups (H2-H4, repetitive hypoxia for 2-4 runs respectively).</p><p><b>RESULTS</b>(1) The MMP- 2 expression level was increased first then decreased in hippocampus and the significant decrease was found in H4 group (P < 0.05, n=6), but no significant changes among the 5 groups in cortex. In addition, no activated form of 66 kD MMP-2 had been detected both in hippocampus and cortex. (2) Along with the development of brain hypoxic preconditioning, the level MMP-9 protein expression also increased first then decreased gradually in hippocampus, and the significant changes were found both in H1 and H4 groups (P < 0.05, n=7 for each group). The same trace of changes was also found in the activation of MMP-9 (include 82 and 78 kD forms) in hippocampus, and the significance both in H1 and H4 (P < 0.05, n=7 for each group) were detected. However, there was not any significant change in the level of MMP-9 protein expression or activation to be found in cortex.</p><p><b>CONCLUSION</b>These results suggested that MMP-2 and MMP-9 might play certain role in the development of cerebral hypoxic preconditioning, the different changes of MMP-2/9 protein expression and activation both in cortex and hippocampus might be involved in their selective vulnerability to hypoxia.</p>