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Cotton aphids (Aphis gossypii Glover) are important pests of cucurbit crops. Plant defenses at different cell layers, including the leaf surface, mesophyll cells, and phloem, are employed to defend aphids. Here, we assessed differences in aphid resistance among six watermelon varieties and elucidated the defense mechanisms underlying aphid-resistant/susceptible watermelon varieties. The population abundance, offspring number per female, and meantime of phloem-feeding (E2 phase) of aphids were the highest on XiNong (XN), followed by JingXin (JX), TianWang (TW), ZaoJia (ZJ), and MeiFuLai (MFL), and these parameters were the lowest on JinMeiDu (JMD). Further analyses showed that there was no correlation between the aphid resistance of six watermelon varieties and defenses at the leaf surface. For defenses at mesophyll cells, aphid infestation increased salicylic acid (SA) content at 48 h post-infestation (hpi) and ROS accumulation at 6 and 12 hpi in six watermelon varieties. For phloem defenses, aphid infestation increased callose content in JMD plants but decreased callose content in JX, TW, ZJ, MFL, and XN plants at 6, 12, 24, and 48 hpi. Moreover, callose deposition suppressed by 2-deoxy-d-glucose (2-DDG) neutralized the resistance of JMD plants and exacerbated the susceptibility of XN plants to aphids, which exhibited a higher population abundance and E2 phase time. Collectively, phloem defenses regulated by aphid-induced callose deposition were responsible for differences in aphid resistance among the watermelon varieties. [ABSTRACT FROM AUTHOR]

Summary: This paper presents an adaptive fuzzy control approach of multiple‐input–multiple‐output (MIMO) switched uncertain systems, which involve time‐varying full state constraints (TFSCs) and unknown disturbances. In the design procedure, the fuzzy logic systems are adopted to approximate the unknown functions in the systems. The adaptive fuzzy controller is set up by backstepping technique. According to the tangent barrier Lyapunov function (BLF‐Tan), a novel adaptive MIMO switched nonlinear control algorithm is designed. Under the rule of arbitrary switchings and the proposed control laws, it is demonstrated that all signals in the resulted system are semiglobally uniformly ultimately bounded (SGUUB) and the tracking error converges to a small neighborhood of zero with TFSCs. Furthermore, the simulation example validates the effectiveness of presented control strategy. [ABSTRACT FROM AUTHOR]

Summary: This paper is concerned with adaptive tracking control for switched uncertain nonlinear systems, which contain the time‐varying output constraint (TVOC) and input asymmetric saturation characteristic. In response to the unknown functions, the fuzzy logic systems are adopted. The controller is constructed by the backstepping technique. Based on the Tangent Barrier Lyapunov Function (BLF‐Tan), an adaptive switched control scheme is designed. It is demonstrated that all signals in the resulted system are semiglobally uniformly ultimately bounded with TVOC under arbitrary switchings. Furthermore, the effectiveness of presented control method is validated via the simulation example. [ABSTRACT FROM AUTHOR]

Polytyism of micas is ubiquitous in natural rocks and can be used as an indicator of physical and chemical conditions in related diagenetic processes. To reveal the formation mechanisms of different polytypes, 1M- and 2M1-fluorophlogopite were synthesized using the melting method, and experiments with different Al concentration in the initial reactants were also performed. The structure refinement indicates that the space group of the 1M-fluorophlogopite is C2/m, and the lattice parameters are a = 5.2941(4) Å, b = 9.1773(6) Å, c = 10.1061(7) Å, β = 100.141(7)°. The space group of the 2M1-fluorophlogopite is C2/c, and the lattice parameters are a = 5.3094(16) Å, b = 9.1973(28) Å, c = 20.0442(60) Å, β = 95.141(7)°. The isomorphous substitution of Al3+ for Si4+ in tetrahedral sites of fluorophlogopite causes distortion in the layer structure, and results in a larger tetrahedral rotation angle α, longer tetrahedral bond distance, smaller tetrahedral flattening angle τ, larger bond length difference between inner and outer potassium–oxygen (∆〈K–O〉mean), and relative higher value of octahedral flattening angle ψ. Our experimental results suggest that the content of structural Al has no correlation with the polytype formation, whereas the Al concentration in reactants influences the formation of 1M- and 2M1-fluorophlogopite. [ABSTRACT FROM AUTHOR]

Objectives: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is characterized by strategic white matter (WM) hyperintensities on MRI. Pathological features include WM degeneration, arteriolosclerosis, lacunar infarcts, and the deposition of granular osmiophilic material. Based on the hypothesis that the gliovascular unit is compromised, we assessed the nature of astrocyte damage in the deep WM of CADASIL subjects. Methods: We evaluated post‐mortem brains from CADASIL, cerebral small vessel disease, similar age cognitively normal and older control subjects. Standard immunohistochemical, immunofluorescent, and unbiased stereological methods were used to evaluate the distribution of astrocytes, microvessels, and autophagy markers in five different brain regions. Results: Compared to the controls, the deep WM of CADASIL subjects overall showed increased numbers of glial fibrillary acidic protein (GFAP)‐positive clasmatodendritic astrocytes (P=0.037) and a decrease in the percentage of normal appearing astrocytes (P=0.025). In accord with confluent WM hyperintensities, the anterior temporal pole contained abundant clasmatodendritic astrocytes with displaced aquaporin 4 immunoreactivity. Remarkably, we also found strong evidence for the immunolocalization of autophagy markers including microtubule‐associated protein 1, light chain 3 (LC3), and sequestosome 1/p62 and Caspase‐3 in GFAP‐positive clasmatodendritic cells, particularly within perivascular regions of the deep WM. LC3 was co‐localized in more than 90% of the GFAP‐positive clasmatodendrocytes. Conclusions: Our novel findings show astrocytes undergo autophagy‐like cell death in CADASIL, with the anterior temporal pole being highly vulnerable. We propose astrocytes transform from normal appearing type A to hypertrophic type B and eventually to clasmatodendritic type C cells. These observations also suggest the gliovascular unit of the deep WM is severely impaired in CADASIL. [ABSTRACT FROM AUTHOR]

Both the inflammatory potential and cognitive function decline during aging. The association between the repertoire of inflammatory biomarkers and cognitive decline is unclear. Inflammatory cytokines have been reported to be increased, decreased, or unchanged in the cerebrospinal fluid and sera of subjects with dementia. We assessed 112 postmortem brains from subjects diagnosed with poststroke dementia (PSD), vascular dementia, mixed dementia, and Alzheimer's disease (AD), comparing those to poststroke nondemented (PSND) subjects and age-matched controls. We analyzed 5 brain regions including the gray and white matter from the frontal and temporal lobes for a panel of cytokine and/or chemokine analytes using multiplex-array assays. Of the 37 analytes, 14 were under or near the detection limits, 7 were close to the lowest detection level, and 16 cytokines were within the linear range of the assay. We observed widely variable concentrations of C-reactive protein (CRP) and serum amyloid A at the high end (1–150 ng/mg protein), whereas several of the interleukins (IL, interferon-gamma and tumor necrosis factor) at the low end (1–10 pg/mg). There were also regional variations; most notable being high concentrations of some cytokines (e.g., CRP and angiogenesis panel) in the frontal white matter. Overall, we found decreased concentrations of several cytokines, including IL-1 beta ( p = 0.000), IL-6 ( p = 0.000), IL-7 ( p = 0.000), IL-8 ( p = 0.000), IL-16 ( p = 0.001), interferon-inducible protein–10 (0.044), serum amyloid A ( p = 0.011), and a trend in IL-1 alpha ( p = 0.084) across all dementia groups compared to nondemented controls. IL-6 and IL-8 were significantly lower in dementia subjects than in nondemented subjects in every region. In particular, lower levels of IL-6 and IL-8 were notable in the PSD compared to PSND subjects. Because these 2 stroke groups had comparable degree of vascular pathology, the lower production of IL-6 and IL-8 in PSD reaffirms a possible specific involvement of immunosenescence in dementia pathogenesis. In contrast, CRP was not altered between dementia and nondementia subjects or between PSD and PSND. Our study provides evidence not only for the feasibility of tracking cytokines in postmortem brain tissue but also suggests differentially impaired inflammatory mechanisms underlying dementia including AD. There was a diminished inflammatory response, possibly reflecting immunosenescence and cerebral atrophy, in all dementias. Strategies to enhance anti-inflammatory cytokines and boost the immune system of the brain may be beneficial for preventing cognitive dysfunction, especially after stroke. [ABSTRACT FROM AUTHOR]

Propagating optical eigenmodes are found in densely packed monolayers of plasmonic nanoparticles on a metal mirror. FDTD numerical calculations show that these 2D waves carry strongly confined and amplified light energy directly in the layer of nanoparticles or in the gap between the nanoparticles and the mirror. The extreme amplification of light intensity and localization at the nanoscale offer a high potential of these waves for photon emission, light harvesting, and waveguiding applications. [ABSTRACT FROM AUTHOR]

Abstract: Periventricular white matter injury (PVWMI) in premature babies is a major cause of cerebral palsy. Excitotoxic ibotenic acid (IBA) causes PVWMI-like lesions when injected into the white matter of neonatal rodents, however, whether it causes sensorimotor behavioural deficits that could also model cerebral palsy has not been tested. We compared IBA injection at postnatal day 7 (P7) when rodent development is equivalent to the stage of human corticospinal maturation vulnerable to PVWMI and P5 when rodent oligodendrocyte precursor cells are more vulnerable to excitotoxicity. IBA or saline were injected bilaterally into white matter between the external angle of the lateral ventricle and the forelimb sensorimotor cortex. By P14, IBA injection at P5 caused localised hypomyelination and cyst formation in this region, although cortical grey matter remained intact. Treatment at P7 produced less hypomyelination, but more widespread loss of neurofilament immunoreactivity. From P28 onwards, corticospinal function was assessed by testing reaching and retrieval of food rewards. All rats improved with age, but there was a consistent and significant difference between IBA treated rats (P5 and P7) and controls. Histological examination following testing revealed no difference in forebrain cross-sectional area but that the lateral ventricles were significantly larger in IBA treated animals than controls, especially at P7. P5 treatment caused a significantly reduced density of anti-myelin immunoreactivity in the corpus callosum compared to the anterior commissure that was not consistently seen following P7 treatment. We conclude that IBA induced lesions provide a satisfactory model of PVWMI, particularly when made at P5. [Copyright &y& Elsevier]

This study aimed to quantify the different effect of external cuff pressure on arterial volume distensibility between peripheral arteries with different compliance. 30 healthy subjects were studied with the arm at two positions (0° and 45° from the horizontal level) to introduce different compliance of arteries. The electrocardiogram and finger and ear photoplethysmograms were recorded simultaneously under five external cuff pressures (0, 10, 20, 30 and 40 mmHg) on the whole arm to obtain arterial volume distensibility. With the applied external cuff pressures of 10, 20, 30 and 40 mmHg, the overall changes in arterial volume distensibility referred to those without external pressure were 0.010, 0.029, 0.054 and 0.108% per mmHg for the arm at the horizontal level, and 0.026, 0.071, 0.170 and 0.389% per mmHg for the arm at 45° from the horizontal level, confirming the non-linearity between arterial volume distensibility and external pressure. More interestingly, the significant differences in arterial volume distensibility changes were observed between the two arm positions, which were 0.016, 0.043, 0.116 and 0.281% per mmHg (all P < 0.01). Our findings demonstrated that arterial volume distensibility of peripheral arm arteries increased with external pressure, with a greater effect for more compliant arteries. [ABSTRACT FROM AUTHOR]

Results Disordered stacking in molybdenite Micro X-ray diffraction ( -XRD) pattern in Figure 2a revealed that the molybdenite comprised a mixture of 2 I H i SB 1 sb and 3 I R i polytypes (2 I H i SB 1 sb /3 I R i 9:1) ([37]). Keywords: Molybdenite (MoS2); polytype; non-equilibrium crystallization; HAADF-STEM; layered minerals; stacking fault; Applications of Fluid; Mineral; and Melt Inclusions EN Molybdenite (MoS2) polytype non-equilibrium crystallization HAADF-STEM layered minerals stacking fault Applications of Fluid Mineral and Melt Inclusions 997 1006 10 06/01/22 20220601 NES 220601 Introduction Molybdenite (MoS SB 2 sb ) is a layered sulfide mineral that commonly occurs in hydrothermal ore deposits and, like other layered minerals, exhibits polytypism. Graph: Figure 2 Micro X-ray diffraction ( -XRD) and selected-area electron diffraction (SAED) patterns, and transmission electron microscopy (TEM) and high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) images of a disordered molybdenite particle. [Extracted from the article]

Abstract: Two methods for preparing polycrystalline silver shells on colloidal silica spheres are reported. These do not include the use of organic ligands or metal seeding steps and are based on the Tollen''s process for silvering glass. Reaction parameters such as temperature and reactant concentrations are adjusted to slow the reaction kinetics, which we find leads to preferential silver growth on the spheres. The resulting shells are polycrystalline and granular, showing highly uniform sphere coverage. Surface morphologies range from sparsely interconnected grains for shells ∼20 nm thick, to complete (yet porous) shells of interconnected silver clusters which are up to ∼140 nm in thickness. The extinction spectra of the core–shell materials are markedly different from those of smooth continuous shells, showing clear evidence that the granular shell geometry influences the plasmon resonance of the composite system. Spheres coated with shells 20–40 nm thick are also suitable for colloidal crystallization. Monolayers of self-assembled spheres with long-range ordering are demonstrated. [Copyright &y& Elsevier]

Background: Gestational diabetes mellitus (GDM) is a metabolic disease that seriously endangers the health of mothers and children. It is important to monitor GDM in real-time before diagnosis and to prevent it effectively.Objective: GDM was divided into the second trimester diagnosed diabetes mellitus (GDM_24) and the third trimester diagnosed diabetes mellitus (GDM_30). The risk prediction of two types of GDM was performed in normal pregnant women at 11-13 and 16-19 weeks of pregnancy, respectively.Methods: By stages, the K-W test was used to analyze the differences between basic information and energy metabolism factors, and multiple logistic regression was used to analyze the risk of energy metabolism factors and to correct the confounders with significant differences.Results: For the GDM_24 group, each additional unit of oxygen consumption (VO2), carbon dioxide production, and resting energy expenditure (REE) increased the risk by 2.4%, 3.5%, 0.4%, and 2.1%, 2.6%, and 0.3%, respectively, at 11-13 and 16-19 weeks of pregnancy. For the GDM_30 group, each additional unit of VO2 and REE was associated with an increased risk of 2.3% and 0.3%, respectively, at 16-19 weeks of pregnancy.Conclusion: The risk of GDM_30 only appeared in pregnant women during 16-19 weeks of pregnancy, which may indicate that GDM_24 and GDM_30 have different pathogenesis. [ABSTRACT FROM AUTHOR]

Fetal weight is one of the important indicators for judging whether fetal growth and development are normal. Fetal weight exceeding the normal range may lead to poor delivery outcomes. We aimed to establish a personalized fetal growth curve in order to effectively monitor fetal growth during pregnancy. Fetal weight can be monitored while fetal growth and development are assessed. This study retrospectively analyzed the birth weight and ultrasound database of 3,093 newborns delivered at normal term. The personalized fetal growth curve model was generated based on the birth weight formula established by Gardosi combined with the proportional weight equation. (1) The average birth weight of the single fetus at normal term was 3,457g. (2) According to the regression results of the proportion of fetal weight in full-term pregnancy and gestational week, the proportional weight equation is Weight% = 500.9 - 51.60GA + 1.727GA2- 0.01718GA3 (GA is gestational week), R2 is 98%, P< 0.001. In this study, the normal birth weight of newborns and normal range of fetal weight can be estimated by using the personalized fetal growth curve model. [ABSTRACT FROM AUTHOR]

Oral glucose tolerance test (OGTT) is the standard for the diagnosis of gestational diabetes mellitus (GDM). However, clinically, some cases with normal results were diagnosed as GDM in the third trimester. To establish a risk model based on energy metabolism, epidemiology, and biochemistry that could predict the GDM pregnant women with normal OGTT results in the second trimester. Qualitative and quantitative data were analyzed to find out the risk factors, and the binary logistic backward LR regression was used to establish the prediction model of each factor and comprehensive factor, respectively. The risk factors including the rest energy expenditure per kilogram of body weight, oxygen consumption per kilogram of body weight, whether to meet the weight gain criteria of the Institute of Medicine, the increase of body mass index between the second trimester and pre-pregnancy, and fasting blood glucose. By comparison, the comprehensive model had the best prediction performance, indicating that 85% of high-risk individuals were correctly classified. Energy metabolism, epidemiology, and biochemistry had better recognition ability for the GDM pregnant women with normal OGTT results in the second trimester. The addition of metabolic factors in the second trimester also improved the overall prediction performance. [ABSTRACT FROM AUTHOR]

Monitoring fetal weight during pregnancy has a guiding role in prenatal care. To establish a personalized fetal growth curve for effectively monitoring fetal growth during pregnancy. (1) This study retrospectively analyzed the birth weight database of 2,474 singleton newborns delivered normally at term. The personalized fetal growth curve model was formed by combining the estimating birth weight of newborns with the proportional weight formula. (2) Multiple linear stepwise regression method was used to estimate the birth weight of newborns. (1) Delivery GA, weight at first visit, maternal height, pre-pregnancy body mass index, fetal sex, parity had significant effects on birth weight. Based on these parameters, the formula for calculating term optimal weight was obtained (R2= 22.8%, P< 0.001). (2) The personalized fetal growth curve was obtained according to the epidemiological factors input model of each pregnant woman. A model of personalized fetal growth curve can be established, and be used to evaluate fetal growth and development through estimated fetal weight monitoring. [ABSTRACT FROM AUTHOR]

The prediction of hypertensive disorders in pregnancy (HDP) mainly involves various aspects such as maternal characteristics and biomarkers. We aimed to study the effect of the HDP prediction model with or without placental growth factor (PlGF). This study used maternal factors and PlGF, and standardized the data uniformly. At 12–20 weeks, the comprehensive comparison of model quality with or without PlGF was conducted by logistic regression. The area under curve and the model accuracy of the model with PlGF were higher than those of the model without PlGF. The accuracy of the model with PlGF was above 90%. Adding PlGF to the model for predicting HDP improved the accuracy and effectiveness of the model. This study confirmed the predictive performance of PlGF. [ABSTRACT FROM AUTHOR]

Placental growth factor (PlGF), one of the biomarkers, has a certain predictive effect on hypertensive disorders in pregnancy (HDP).To study the HDP prediction effect of different methods for variable selection and modeling for models containing PlGF. For the model containing PlGF, the appropriate range of PlGF parameters needed to be selected. Step-logistic regression and lasso were used to compare the model effect of twice range selection. The PlGF model with good predictive effect and appropriate detecting gestational age was selected for the final prediction.The effect of the model containing PlGF tested at 15–16 weeks was better than the PlGF value without comprehensive screening. The sensitivity of both methods was over 92%. By comprehensive comparison, the final model of lasso method in this study was more effective.In this study, a variety of methods were used to screen models containing PlGF parameters. According to clinical needs and model effects, the optimal HDP prediction model with PlGF parameters in the second trimester of 15–26 weeks of pregnancy was finally selected. [ABSTRACT FROM AUTHOR]

White matter (WM) disintegration is common in the older population and is associated with vascular cognitive impairment (VCI). This study explored the effects of environmental enrichment (EE) on pathological sequelae in a mouse model of chronic cerebral hypoperfusion induced by bilateral common carotid artery stenosis (BCAS). Male C57BL/6 J mice underwent BCAS or sham surgery. One-week after surgery, mice were exposed to three different degrees of EE; either standard housing conditions (std), limited 3 h exposure to EE per day (3 h) or full-time exposure to EE (full) for 12 weeks. At 13 weeks after surgery, cognitive testing was performed using a three-dimensional 9-arm radial maze. At 16 weeks after surgery, nesting ability was assessed in each mouse immediately before euthanasia. Brains retrieved after perfusion fixation were examined for WM pathology. BCAS caused WM changes, as demonstrated by corpus callosum atrophy and greater WM disintegrity. BCAS also caused impaired nesting ability and cognitive function. These pathological changes and working memory deficits were attenuated, more so by limited rather than full-time exposure to EE regime. Our results suggest that limited exposure to EE delays the onset of WM degeneration. Therefore, the implementation of even limited EE may be beneficial for patients diagnosed with VCI. [ABSTRACT FROM AUTHOR]

This study aimed to quantify blood pressure (BP) measurement accuracy and variability with different techniques. Thirty video clips of BP recordings from the BHS training database were converted to Korotkoff sound waveforms. Ten observers without receiving medical training were asked to determine BPs using (a) traditional manual auscultatory method and (b) visual auscultation method by visualizing the Korotkoff sound waveform, which was repeated three times on different days. The measurement error was calculated against the reference answers, and the measurement variability was calculated from the SD of the three repeats. Statistical analysis showed that, in comparison with the auscultatory method, visual method significantly reduced overall variability from 2.2 to 1.1 mmHg for SBP and from 1.9 to 0.9 mmHg for DBP (both p<0.001). It also showed that BP measurement errors were significant for both techniques (all p<0.01, except DBP from the traditional method). Although significant, the overall mean errors were small (−1.5 and −1.2 mmHg for SBP and −0.7 and 2.6 mmHg for DBP, resp., from the traditional auscultatory and visual auscultation methods). In conclusion, the visual auscultation method had the ability to achieve an acceptable degree of BP measurement accuracy, with smaller variability in comparison with the traditional auscultatory method. [ABSTRACT FROM AUTHOR]

This study aimed to compare within-subject blood pressure (BP) variabilities from different measurement techniques. Cuff pressures from three repeated BP measurements were obtained from 30 normotensive and 30 hypertensive subjects. Automatic BPs were determined from the pulses with normalised peak amplitude larger than a threshold (0.5 for SBP, 0.7 for DBP, and 1.0 for MAP). They were also determined from cuff pressures associated with the above thresholds on a fitted curve polynomial curve of the oscillometric pulse peaks. Finally, the standard deviation (SD) of three repeats and its coefficient of variability (CV) were compared between the two automatic techniques. For the normotensive group, polynomial curve fitting significantly reduced SD of repeats from 3.6 to 2.5 mmHg for SBP and from 3.7 to 2.1 mmHg for MAP and reduced CV from 3.0% to 2.2% for SBP and from 4.3% to 2.4% for MAP (all P<0.01). For the hypertensive group, SD of repeats decreased from 6.5 to 5.5 mmHg for SBP and from 6.7 to 4.2 mmHg for MAP, and CV decreased from 4.2% to 3.6% for SBP and from 5.8% to 3.8% for MAP (all P<0.05). In conclusion, polynomial curve fitting of oscillometric pulses had the ability to reduce automatic BP measurement variability. [ABSTRACT FROM AUTHOR]

Background: This study was designed to explore the beneficial effects of environmental enrichment (EE) on white matter glial changes in a mouse model of chronic cerebral hypoperfusion induced by bilateral common carotid artery stenosis (BCAS).Methods: A total of 74 wild-type male C57BL/6J mice underwent BCAS or sham surgery. One week after surgery, the mice were randomly assigned into three different groups having varied amounts of EE-standard housing with no EE conditions (std), limited exposure with 3 h EE a day (3 h) and full-time exposure to EE (full) for 12 weeks. At 16 weeks after BCAS surgery, behavioural and cognitive function were assessed prior to euthanasia. Brain tissues were analysed for the degree of gliosis including morphological changes in astrocytes and microglia.Results: Chronic cerebral hypoperfusion (or BCAS) increased clasmatodendrocytes (damaged astrocytes) with disruption of aquaporin-4 immunoreactivity and an increased degree of microglial activation/proliferation. BCAS also impaired behavioural and cognitive function. These changes were significantly attenuated, by limited exposure compared to full-time exposure to EE.Conclusions: Our results suggest that moderate or limited exposure to EE substantially reduced glial damage/activation. Our findings also suggest moderate rather than continuous exposure to EE is beneficial for patients with subcortical ischaemic vascular dementia characterised by white matter disease-related inflammation. [ABSTRACT FROM AUTHOR]

Aim Brain clusterin is known to be associated with the amyloid-β deposits in Alzheimer's disease ( AD). We assessed the distribution of clusterin immunoreactivity in cerebrovascular disorders, particularly focusing on white matter changes in small vessel diseases. Methods Post-mortem brain tissues from the frontal or temporal lobes of a total of 70 subjects with various disorders including cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy ( CADASIL), cerebral amyloid angiopathy ( CAA) and AD were examined using immunohistochemistry and immunofluorescence. We further used immunogold electron microscopy to study clusterin immunoreactivity in extracellular deposits in CADASIL. Results Immunostaining with clusterin antibodies revealed strong localization in arterioles and capillaries, besides cortical neurones. We found that clusterin immunostaining was significantly increased in the frontal white matter of CADASIL and pontine autosomal dominant microangiopathy and leukoencephalopathy subjects. In addition, clusterin immunostaining correlated with white matter pathology severity scores. Immunostaining in axons ranged from fine punctate deposits in single axons to larger confluent areas with numerous swollen axon bulbs, similar to that observed with known axon damage markers such as non-phosphorylated neurofilament H and the amyloid precursor protein. Immunofluorescence and immunogold electron microscopy experiments showed that whereas clusterin immunoreactivity was closely associated with vascular amyloid-β in CAA, it was lacking within the granular osmiophilic material immunolabelled by NOTCH3 extracelluar domain aggregates found in CADASIL. Conclusions Our results suggest a wider role for clusterin associated with white matter damage in addition to its ability to chaperone proteins for clearance via the perivascular drainage pathways in several disease states. [ABSTRACT FROM AUTHOR]

White matter hyperintensities as seen on brain T2-weighted magnetic resonance imaging are associated with varying degrees of cognitive dysfunction in stroke, cerebral small vessel disease and dementia. The pathophysiological mechanisms within the white matter accounting for cognitive dysfunction remain unclear. With the hypothesis that gliovascular interactions are impaired in subjects with high burdens of white matter hyperintensities, we performed clinicopathological studies in post-stroke survivors, who had exhibited greater frontal white matter hyperintensities volumes that predicted shorter time to dementia onset. Histopathological methods were used to identify substrates in the white matter that would distinguish post-stroke demented from post-stroke non-demented subjects. We focused on the reactive cell marker glial fibrillary acidic protein (GFAP) to study the incidence and location of clasmatodendrosis, a morphological attribute of irreversibly injured astrocytes. In contrast to normal appearing GFAP+ astrocytes, clasmatodendrocytes were swollen and had vacuolated cell bodies. Other markers such as aldehyde dehydrogenase 1 family, member L1 (ALDH1L1) showed cytoplasmic disintegration of the astrocytes. Total GFAP+ cells in both the frontal and temporal white matter were not greater in post-stroke demented versus post-stroke non-demented subjects. However, the percentage of clasmatodendrocytes was increased by >2-fold in subjects with post-stroke demented compared to post-stroke non-demented subjects (P = 0.026) and by 11-fold in older controls versus young controls (P < 0.023) in the frontal white matter. High ratios of clasmotodendrocytes to total astrocytes in the frontal white matter were consistent with lower Mini-Mental State Examination and the revised Cambridge Cognition Examination scores in post-stroke demented subjects. Double immunofluorescent staining showed aberrant co-localization of aquaporin 4 (AQP4) in retracted GFAP+ astrocytes with disrupted end-feet juxtaposed to microvessels. To explore whether this was associated with the disrupted gliovascular interactions or blood-brain barrier damage, we assessed the co-localization of GFAP and AQP4 immunoreactivities in post-mortem brains from adult baboons with cerebral hypoperfusive injury, induced by occlusion of three major vessels supplying blood to the brain. Analysis of the frontal white matter in perfused brains from the animals surviving 1-28 days after occlusion revealed that the highest intensity of fibrinogen immunoreactivity was at 14 days. At this survival time point, we also noted strikingly similar redistribution of AQP4 and GFAP+ astrocytes transformed into clasmatodendrocytes. Our findings suggest novel associations between irreversible astrocyte injury and disruption of gliovascular interactions at the blood-brain barrier in the frontal white matter and cognitive impairment in elderly post-stroke survivors. We propose that clasmatodendrosis is another pathological substrate, linked to white matter hyperintensities and frontal white matter changes, which may contribute to post-stroke or small vessel disease dementia. [ABSTRACT FROM AUTHOR]

The article describes research report on Detrital Zircon U-Pb Geochronology of the Triassic Sandstones from the Yanyuan Basin of Southwestern Sichuan, China. Topics discusses include Triassic sandstones in the Yanyuan Basin record different detrital zircon geochronology signals; and supported by the Sichuan Science and technology program the open fund of State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Chengdu University of Technology.

In this study, beidellite, paragonite and other 2:1 type layered aluminosilicates with high layer charges (2:1 type LA-HLC) were synthesized under hydrothermal conditions by using boehmite as a precursor. The concentrations of dissolved Al from boehmite precursor had important effects on the mineral components of the hydrothermal products and the layer charge density of the resultant minerals. A combination of 2:1 type LA-HLC, paragonite, and minor beidellite formed at a relatively high concentration of dissolved Al, while beidellite with a small amount of 2:1 type LA-HLC was produced at a low concentration of dissolved Al. The resultant 2:1 type LA-HLC exhibited poor swelling ability when treated with ethylene glycol. A solid-state transformation mechanism was proposed for the transformation based on the HRTEM images and EDS analyses, which showed that lattice fringes representing (001) faces of 2:1 type layered aluminosilicates (2:1 type LA) were parallel to the (020) direction of boehmite. The successful transformation of boehmite into 2:1 type LA provides insights to well understand the formation of 2:1 type LA in geological processes and offer a facile preparation approach for the synthesis of 2:1 type LA with different layer charges. • Boehmite could be transformed into 2:1 type layered aluminosilicates under hydrothermal conditions. • 2:1 type layered aluminosilicates with high layer charges exhibited poorly swelling ability after ethylene glycol treatment. • Layer charges of 2:1 type layered aluminosilicates were estimated based upon the 29Si NMR spectra results. • Dissolved Al from boehmite had effects on the layer charge density of 2:1 type layered aluminosilicates. [ABSTRACT FROM AUTHOR]