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Verticillium wilt (Verticillium dahliae Kleb.) is a fungal disease of sunflower plants causing vascular bundle jamming, leaf wilt, and plant death, all of which affect sunflower production. We devised an artificial inoculation field test to investigate Verticillium wilt incidence during different stages of sunflower growth including seedling, flowering, and maturation stages, to assess the impact of different disease appearance period on plant growth and production. We hypothesized that time of symptom appearance may be a key factor for sunflower development. The results showed that Verticillium wilt dramatically inhibited sunflower growth and production in all three developmental stages. The disease incidence of Verticillium wilt, considered as percentage of symptomatic plants, was higher than 60% at the maturation stage and lower than 20% at the seedling stage. However, the greatest yield suppression was identified at the seedling stage, while yield inhibition was relatively limited during the flowering and maturation stages. Therefore, the earlier the symptom appearance is established in sunflower development, the greater is the suppression of plant growth, indicating that seedling management is crucial in controlling the Verticillium wilt. The outcomes of this study would contribute to the development of disease control strategies to improve sunflower production.

Circular hollow section (CHS) specimens are widely employed in long-span space structures, truss structures, and bridge structures; however, only a few experimental and numerical investigations on CHS aluminum alloy beams have been conducted in China. This paper presents a detailed experimental investigation on CHS beams made of 6082-T6 aluminum alloys. The effects of length and section slenderness on the ultimate strength and buckling behaviour were investigated. Seventeen extruded CHS specimens were subjected to four-point bending tests, with the diameter-to-thickness ratio (D/t) ranging from 16.4 to 29.1. The failure modes observed included overall buckling and the coupling of local and overall buckling. The initial geometric imperfections were measured prior to the bending tests. Subsequently, fine finite-element (FE) models were developed using the nonlinear analysis program ABAQUS and validated against the experimental results. An extensive parametric study involving 600 numerical results was performed to evaluate the effects of D/t, the section dimensions, and the slenderness ratio on the mechanical responses and bending strength of the CHS beams. The test results, together with the obtained FE analysis results, were utilised to assess the accuracy of the bending-strength provisions in the current design codes GB 50429 (China), Eurocode 9 (Europe), and AA-2015 (America), as well as optional design approaches, i.e. the direct strength method (DSM) and continuous strength method (CSM). The results indicated that all five design provisions provided conservative predictions of the ultimate moment capacities; the predicted results of DSM and CSM were more accurate than the three design specifications. The reliability levels of the bending-strength provisions were confirmed and compared using statistical parameters from the corresponding specifications.

Caudal paramedian midbrain infarction (CPMI) is an extremely rare form of ischemic stroke and related clinical studies are scarce. Our aim is to investigate the clinical features, neuroradiological findings and stroke etiology of CPMI. We conducted a retrospective study of 12 patients with CPMI, confirmed by diffusion-weighted MRI from 6820 cerebral infarction patients at our stroke center from January 2012 to August 2018. Experienced neurologists evaluated the clinical manifestations, neuroimaging findings and stroke mechanisms. Twelve patients (11 men, 1 woman) aged 42-81 years old met the study inclusion criteria. Seven patients had a unilateral infarction (two right-sided, five left-sided) and five had bilateral infarctions. Sagittal image showed a backward oblique sign in the lower level of the midbrain. Significantly, the bilateral CPMIs presented with a characteristic "V-shaped" appearance in the axial MRI. All patients presented with bilateral cerebellar dysfunction which included dysarthric speech, truncal or gait ataxia and four-limb ataxia. In addition, diplopia and internuclear ophthalmoplegia were frequently encountered in CPMI. Five (41.7%) patients were classified with large artery atherosclerosis, four (33.3%) with small vessel disease, two (16.7%) with cardiogenic embolism, and one (8.3%) with undetermined etiology. CPMI is a rare cerebrovascular disease that destroys the Wernekink commissure, medial longitudinal fasciculi and other adjacent structures. It is characterized by bilateral cerebellar ataxia and eye movement disorders, mainly internuclear ophthalmoplegia. A distinct "V-shaped" radiological feature can be seen in bilateral CPMI patients. The primary mechanisms of unilateral CPMI involve small vessel disease. The underlying stroke mechanisms of bilateral CPMI are either large artery atherosclerosis disease or cardiac embolism.

With population growth and aging, more and more patients with cerebral infarction have varying degrees of disability. ATP-sensitive potassium (KATP) channels regulate many cellular functions by coupling metabolic status with cell membrane electrical activity. Nicorandil (N-(2-hydroxyethyl)-nicotinamide nitrate) is the first KATP channel opener approved for clinical use. It has been reported that it might exert protective effects on the cerebral infarction by increasing cerebral blood flow and reducing inflammation. However, only a few studies explored its role in synaptogenesis. We made the rat model of middle cerebral artery occlusion (MCAO). Nicorandil was administered to rats via oral administration immediately after the surgery at a dose of 7.5 mg/kg and then daily for the next days. Infarct volume, cerebral edema, neurological deficits, cognitive impairment, and the level of Synaptophysin (SYP)、Growth associated protein-43 (GAP43) and neuronal nuclear antigen (NeuN) levels were measured to evaluate the effect of nicorandil. Our data showed that nicorandil treatment could decrease brain damage, improve learning and memory, and increase SYP、GAP43 and NeuN level. Taken together, we propose that nicorandil, as an opener of the KATP channel, provides a neuroprotective role in MCAO by promoting synaptic connections.

Alzheimer’s disease (AD) is a major form of dementia among neurodegenerative diseases, which results in memory loss and attention deficits. Syringic acid (SA) is a phenolic compound derivative of plants and fruits, which possessed the numerous biological activities. The present study aims to examine the neuroprotective potential of SA on aluminium chloride (AlCl3) stimulated behavioral deficits and neuroinflammation in the rat AD. The AlCl3 (100 mg/kg.b.wt) via injected intraperitoneally for 60 days to stimulate the AD. The rats were supplemented with low and high doses of SA (25 & 50 mg/kg.b.wt) of SA for 30 days. After end of the experiment, we evaluated behavioral examinations like Morris water maze, Y-maze, elevated plus maze and open field test. Followed by acetylcholinesterase (AChE), biochemical measurement and inflammatory protein expression by western blotting were examined. AD rats displayed reduced memory and learning impairments, augmented short term memory loss and diminished locomotion activity. Interestingly, the neurobehavioral impairments were appreciably stabilized by the SA supplementation to the AD rats. The NF-ƙB, IL-1β, IL-6, and TNF-α expressions were assuaged via the SA supplementation to AD rats. The present work demonstrated that the SA treatment ameliorated the AlCl3 stimulated AD.

The transmission of gun is limited by the structure. Gun has certain backlash and elastic deformation when the servo system is running. In case of large backlash and elastic deformation, the feedback from the motor side or from the load side can not complete the system stability and tracking accuracy very well. By analyzing the characteristics of feedback from the motor side and from the load side, a control strategy of dual position feedback is put forward. It is proved that the dual position feedback can effectively improve the accuracy of the servo system by the experiment in the servo system of a gun.

Aiming at the random disturbance in the tracking and shooting state of the remote control weapon station, stm32f407 is used as the main control unit to design the fractional order composite controller. A method of parameter self-tuning of the fractional order controller based on the improved particle swarm optimization algorithm is proposed, which focuses on the research of obtaining the digital implementation method of fractional order control algorithm. Based on the short memory rule and the time domain numerical method of calculus operator, the fractional order digital discretization is realized, and the experiment is carried out in the system debugging, and the ideal control effect is achieved.

In order to improve the cruising range, and operating characteristics, the safety and reliability of electric vehicles, a collaborative optimal control strategy of multi disk permanent magnet synchronous motor for electric vehicles is proposed. Firstly, the mathematical model of the multi disk PMSM is established, and the efficiency optimization control strategy based on the efficiency map is proposed, and the efficiency optimization control method of the multi disk PMSM is analyzed. Secondly, on the basis of efficiency optimization, a torque collaborative control strategy is proposed, in which fuzzy control is used to optimize the torque fluctuation. Finally, the simulation analysis and vehicle test are carried out for the proposed control strategy. The results show that the modular multi disk PMSM collaborative optimization drive system has a wider range of high efficiency, widens the system efficiency platform, increases the range, and improves the system motion characteristics, which has significantly theoretical research significance and application value.

High precision turntable control systems have high requirements for motor control performance. This paper provides a vector control scheme of permanent magnet synchronous motor (PMSM) based on fuzzy neural network. With fuzzy neural network controller (FNNC) as the current regulator, a fuzzy controller is introduced in the speed loop, and its output is used as the current loop limit to achieve the purpose of speed limit. Simulation and experimental results show that for the complex situation of turntable operation, the method has good torque tracking and motor speed limit performance.

The reliability and safety of aluminum alloy columns used in China is not well understood. This paper develops an improved probabilistic model for the reliability assessment of axially and eccentrically loaded columns, designed based on the aluminum alloy structure design codes of China. A comprehensive database, including 272 axially and 116 eccentrically loaded columns mainly made of 6061-T6 and 6082-T6 aluminum alloy in China, was established. Using this database, a statistical analysis of test results was conducted to determine the optimal probability distribution which can provide the best fit to the model error (ME) data and the relevant distribution parameters. The statistical parameters of ME, material strength, geometrical properties, load type, and load ratio were considered in the reliability evaluation, and a sensitivity analysis was performed to investigate the effect of these variables on the reliability indices. Then, the structural reliability levels of aluminum alloy columns in compression designed according to Chinese, American, and European codes were compared. By analyzing the optimal probability distribution of ME, the calculation results showed that the safety level of Eurocode 9 was the highest, while that of the American code was the lowest, with the Chinese code being in between. Additionally, the reliability index of 6082-T6 aluminum alloy columns was higher than that of 6061-T6. In view of the analysis results showing that the Chinese code barely met the target reliability index of 3.70, the material partial factor γ R was modified for a capacity prediction model of aluminum alloy columns in compression designed according to Chinese code, to ensure that it reached the reliability requirement.

Growth/differentiation factor-5 (GDF-5), a member of the transforming growth factor-beta (TGF-β) superfamily, has been shown to protect rat dopaminergic neurons against insult both in embryonic neuronal culture and in Parkinson’s disease models. However, whether GDF-5 exerts neuroprotective effects in hippocampal neurons is unclear. Here, we show that both mRNA levels and protein levels of GDF-5 are decreased in the mouse hippocampus upon kainic acid (KA) treatment. KA induced dramatic neuronal loss specifically in the cornu ammonis 1 (CA1) and CA3 areas of the mouse hippocampus, while intracerebral infusion of GDF-5 prevented this neuronal loss. The neuroprotective effects of GDF-5 were recapitulated by constitutively active bone morphogenetic protein type IB receptor (BMPRIB-CA) and could be blocked by BMPRI kinase inhibitor LDN-193189. Furthermore, the neuroprotective effects of GDF-5 were mediated through the prevention of apoptosis, which was indicated by terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling (TUNEL) staining and reduced cleaved caspase 3 expression level. Thus, we conclude that GDF-5 protects hippocampal neurons against KA-induced neurodegeneration by signaling through BMPRIB, suggesting a therapeutic potential for GDF-5 in neurodegenerative diseases.

The antibiotic 2,4-diacetylphoroglucinol (2,4-DAPG), produced by the Gram-negative rod-shaped bacterium Pseudomonas fluorescens 2P24, is active against various soil-borne bacterial and fungal pathogens that cause plant diseases. Biosynthesis of 2,4-DAPG is controlled by regulating expression of the phlACBD operon at the post-transcriptional level. The phlG gene is located between the phlF and phlH genes, upstream of the phlACBD biosynthetic operon. Herein, we cloned the phlG gene, generated a phlG deletion mutant, and investigated its regulatory role in 2,4-DAPG biosynthesis. The results showed that deletion of phlG had no effect on the biosynthesis of 2,4-DAPG, but it affected conversion of 2,4-DAPG to its precursor monoacetylphloroglucinol (MAPG). The global regulatory factor encoded by gacS positively regulated expression of phlG, while rsmE negatively regulated its expression. Deleting phlG did not alter the ability of the bacterium to colonise plants or promote plant growth. These results suggest that phlG collaborates with other factors to regulate production of the antibiotic 2,4-DAPG in P. fluorescens 2P24.

Rhinoncus sibiricus Faust, a major pest of buckwheat, has invaded the buckwheat cultivation areas of China for years. This pest was first found in Russia in 1940, causing great damage during the entire buckwheat-growing season. In China, there are few records on R. sibiricus, and studies regarding pest damage on buckwheat are unknown. The occurrence and distribution of this species in China is still not clear. We therefore conducted field surveys for 6 yr to identify the distribution range and the degree of pest damage caused by R. sibiricus in the buckwheat-planting areas of China and tested its preference for two Fagopyrum species in common garden experiments. The results showed that R. sibiricus had a larger distribution range in the Northern rather than the Southern part of China, and that pest damage was more serious in northern China. The pest preferred F. tataricum (Tartary buckwheat, Polygonales: Polygonaceae) over F. esculentum (Common buckwheat, Polygonales: Polygonaceae), but caused damage to both, indicating its potential for distribution in southern China. This study clarified the occurrence, distribution, and damage traits of R. sibiricus in the buckwheat cultivation areas of China, which will help explain the pest attack traits and inform strategies for pest control and prediction.

The plasma diagnosis technology is an essential tool to investigate the plasma characteristics in the pulsed plasma thruster, which can understand the fundamental mechanisms behind pulsed plasma thruster. This review introduces the application of plasma diagnostic technology in pulsed plasma thrusters, investigates the research status of plasma diagnostic technology applied to pulsed plasma thrusters, and discusses usual plasma diagnostics methods. In the contact diagnosis method, the application of Langmuir three probes in the plasma diagnosis of the pulsed plasma thruster is mainly introduced. In the non-contact diagnosis method, the application of optical emission spectroscopy in plasma diagnosis in pulsed plasma thruster is mainly introduced. The advantages and disadvantages of Langmuir three probes and optical emission spectroscopy in plasma diagnosis are analysed.

Background and purpose Inflammation and ferroptosis in astrocytes can be induced by external injuries, which results in excessive production of inflammatory factors and further injury on neurons. Alleviating ferroptosis might be an effective way to protect the brain from external injuries. The present study aims to explore the protective effects of Ferrostatin-1 against ferroptosis induced by Angiotensin II and the underlying mechanism. Methods The mouse primary astrocytes were isolated from the cortices of mice. The astrocytes were stimulated using 10 µM angiotensin II in the presence or absence of 1 or 2 μM Ferrostatin-1. The gene expression levels of AT1R, IL-6, IL-1β, COX-2, GFAP, and GPx4 were evaluated using qRT-PCR. Western Blot was used to determine the protein levels of AT1R, COX-2, GFAP, GPx4, Nrf2, and HO-1 and ELISA was used to detect the concentrations of IL-6, IL-1β, and PGE2. The ROS levels were evaluated using DHE staining and the reduced GSH level was determined using GSH detection kits. Results The expression levels of AT1R, IL-6, IL-1β, COX-2, and GFAP in the astrocytes were significantly elevated by stimulation with Ang II and greatly suppressed by the introduction of Ferrostatin-1 in a dose-dependent manner. The promoted ROS level and inhibited GSH level in the astrocytes by the stimulation with Ang II were significantly reversed by Ferrostatin-1. Down-regulated GPx4, Nrf2, and HO-1 in the astrocytes induced by Ang II were extremely up-regulated by the treatment of Ferrostatin-1 in a dose-dependent manner. Conclusion Ferrostatin-1 alleviates angiotensin II (Ang II)- induced inflammation and ferroptosis by suppressing the ROS levels and activating the Nrf2/HO-1 signaling pathway.

In this study, a detailed experimental investigation of 29 extruded columns with box-type and L-type sections made of 6082-T6 aluminum alloy, was carried out to study the stability behavior of these columns when subjected to eccentric loads. Finite element (FE) models of all tested columns under eccentric loads were developed using the ABAQUS software package. The precision and utility of these FE models were verified by experimental data. Both the stability bearing capacity and deformation performance were evaluated. Using the proposed FE models, an extensive parametric study was performed to investigate the effects of section dimensions, slenderness ratio, and eccentricity on the stability bearing capacity of the eccentrically loaded columns. The test and parametric study results were compared to the design capacity predictions in the current Eurocode 9 and the Chinese Code for the Design of Aluminum Structures, GB 50429. It was found that the predicted stability bearing capacities in the two design codes was generally conservative for the eccentrically loaded columns made of 6082-T6 aluminum alloy. Several parameters of the design formulae from the Chinese Code were modified to predict the ultimate strength of 6082-T6 aluminum alloy columns more accurately.

The wide application of aluminum alloys has been spread in the field of civil and building engineering due to their excellent performance and advantages. The companion paper (Part I) has described the eccentrically compressive loading tests and the verification of finite element (FE) models. In this paper, a parametric study about the 6082-T6 aluminum alloy columns of square and circular hollow sections (SHS-CHS) subjected to eccentric compression was performed using the verified FE models. The key parameters affecting the buckling behaviors and ultimate strength were investigated, including the regularized slenderness ratio, eccentricity, width-thickness ratio (for SHS columns) and diameter-thickness ratio (for CHS columns). The ultimate strength obtained from the previous loading tests and the finite element analysis (FEA) were compared with the design strength predicted by the current Chinese (GB 50429), European (Eurocode 9), American (AA-2010) design codes for aluminum alloy structures. In addition, the newer proposed design method – the direct strength method (DSM), were also investigated. It was found that these four design provisions were generally conservative for predicting the ultimate strength of the SHS and CHS columns for 6082-T6 aluminum alloy and DSM was shown to provide more accurate strength predictions than the current design codes. Finally, the optimal distribution types of the model error (ME) in the four design provisions were investigated and reliability analysis was conducted under different load ratios to evaluate the safety levels of the three current design codes and DSM. Revised Chinses code was proposed to predict the ultimate strength of 6082-T6 aluminum alloy columns more precisely.

Aluminum alloys, which function as load-bearing components or decorative materials, have been commonly applied to architectural structures. In this study, a combination of experiments and finite element analyses was conducted to investigate the stability behaviors and ultimate strengths of the 6082-T6 aluminum alloy columns subjected to eccentric compression. Prior to the loading tests, tensile coupon tests and measurement of the initial geometric imperfections for the columns were performed. The buckling behaviors of 30 pin-ended specimens, including 11 extruded square hollow section (SHS) columns and 19 extruded circular hollow section (CHS) columns, were investigated and the observed failure modes of the tested columns included overall buckling, local buckling and the coupling modes. Meanwhile, the ultimate strengths, deflections and surface strains in whole process under eccentric compression were recorded. The finite element (FE) models of the tested columns were developed using the non-linear finite element analysis (FEA) software ABAQUS, and the geometric and material nonlinearities were considered in the FE models. The validation of the FE models was performed against the test results; it was observed that the proposed FE models are sufficiently accurate to predict the ultimate strengths and buckling behaviors of the tested columns.

Microglia are the major immune cells in the central nervous system and play a key role in brain injury pathology. However, the role of activated microglia after subacute cerebral ischemia (SCI) remains unknown. To address this issue, we established a permanent middle cerebral artery occlusion (pMCAO) rat model and treated pMCAO rats with N-(6-oxo-5,6-dihydro-phenanthridin-2-yl)-N,N-dimethylacetamide (PJ34) (an inhibitor of microglial activation), or with vehicle alone. Finally, we determined the differences between the PJ34-and vehicle-treated rats with respect to neurological deficits, infarct volume, neuronal loss and the expression of CD11b (a marker of microglial activation), glial cell line-derived neurotrophic factor (GDNF) and tumor necrosis factor-α (TNF-α) at 1, 3 and 7 days after treatment. We found that the PJ34-treated rats had more severe neurological deficits and a larger infarct volume and exhibited a decreased CD11b expression, more neuronal loss, decreased expression of GDNF mRNA and protein but increased expression of TNF-α mRNA and protein compared with the vehicle-treated rats at 3 and 7 days after treatment. These results indicate that activated microglia provide a neuroprotective role through balancing GDNF and TNF-α expression following SCI.

Sm0.5Sr0.5Co1−xFexO3 (0 ≤ x ≤ 0.5, SSCF) with perovskite-type structure has been successfully prepared by conventional solid-state reaction as a microwave and infrared multi-functional material. The effects of Fe incorporation on the structure, electrical conductivity, infrared emissivity and microwave-absorbing properties were investigated in detail. XRD results have shown that the perovskite structure of SSCF has an orthorhombic symmetry for 0 ≤ x ≤ 0.4 and a cubic symmetry for 0.5, respectively. The incorporation of Fe in SSCF could contribute to the decrease of electrical conductivity, while the infrared emissivities are increased. Moreover, microwave-absorbing properties in the frequency range of 2–18 GHz at room temperature are sensitive to Fe content. The complex permittivity, complex permeability and electromagnetic loss tangent have suddenly a step change at a certain frequency and the step-change frequency position moves slightly to lower frequencies with Fe increased. The optimal reflection loss calculated from the measured permittivity and permeability is 29.33 dB at 7.97 GHz with a thickness of 2.0 mm.

Objective: To detect the effects of 17β-estradiol (E2) on the expression of calbindin-D9k (CaBP-9k) in pituitary GH3 cells, and to determine the antagonistic effect of a selective estrogen receptor (ER) antagonist (ICI 182 780) on CaBP-9k expression. Methods: A rat pituitary prolactinoma cell line (GH3 cells) was used in an in vitro model. The localization of CaBP-9k in GH3 cells was observed by immunofluorescence. GH3 cells were cultured with the addition of E2 medium for 24 hours. The levels of CaBP-9k mRNA and protein expression in different groups were analyzed by RT-PCR and Western blot analysis. The ER antagonist, ICI 182 780, was added to GH3 cells before E2 (10-8 M) at a concentration of 10-6 M to investigate the regulation of an ER-mediated pathway on CaBP-9k expression. Results: E2 had a stimulatory effect on CaBP-9k expression of GH3 cells in a dose-dependent manner; the level of CaBP-9k expression was higher when treated with a higher concentration of E2. ICI 182 780 suppressed the stimulatory effect of E2 on CaBP-9k expression in GH3 cells. The level of CaBP-9k expression was significantly reduced by co-administration of E2 with ICI 182 780 in GH3 cells. The immunoprecipitation results confirmed that CaBP-9k interacts directly with ERα, and E2 increases the interaction between CaBP-9k and ERα. Conclusion: Estrogen induces CaBP-9k expression via an ERα-mediated pathway and CaBP-9k directly combines with ERα, suggesting that CaBP-9k is involved in the biological effects mediated by an ER pathway in GH3 cells.

This paper presents domain software formal analysis method based on the specification language, and establishes the corresponding framework. A variety of products were collected from software development process, through standard evidence file, formal description based on feature, formal description based on model, and so on stages, they were translated into Raise specification language (RSL) description by formal methods, so that the analysis and verification work can be done through formal tools to analyze domain software. This framework is able to transform all products in the life cycle of domain software into the formal description, to establish solid foundation for formal analysis and construct high reliability software.

Bithalamic infarctions initially presenting as a convulsive seizure are rarely reported and, to our best knowledge, have never been reported in China. Here, we present a patient with convulsive seizure at the onset of bilateral paramedian thalamic infarction. The diffusion-weighted imaging revealed that the infarct area is supplied by Percheron artery. Associated with the relationship between seizure and centrencephalic system and reticular formation as previously reported, we suggest that seizure could be the onset symptom of paramedian thalamic infarction. Physicians should recognize this condition, because both seizure control and early ischemic stroke management are required.

Recent studies have indicated that progesterone (PROG) reduces the expression of inflammatory factors in brain tissue. The present study was designed to investigate whether PROG inhibits the inflammatory response and the infiltration of inflammatory cells in the brain. One hundred and seventy-six adult male Sprague-Dawley rats were randomly divided into four groups: a sham-operated (control) group, a permanent middle cerebral artery occlusion (pMCAO) group, a vehicle-treated group and a PROG-treated group. After pMCAO, the rats received an initial intraperitoneal injection of PROG (8 mg/kg) or vehicle at 1 h post-occlusion, followed by subcutaneous injections at 6, 24 and 48 h. The expression levels of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and CD68 in the brain were measured by immunohistochemistry and Western blotting. The level of myeloperoxidase (MPO) activity was detected by spectrophotometry. The rats were sacrificed 72 h after surgery and isolated brain was sectioned into coronal slices and stained with 2,3,5-triphenyltetrazolium chloride (TTC). Western blotting and spectrophotometry revealed that the expression levels of ICAM-1, VCAM-1, CD68 and MPO were reduced in the brain tissue of PROG-treated rats. In addition, PROG-treated rats showed a substantial reduction in the infarct volume compared to vehicle controls. PROG effectively inhibited the inflammatory response and reduced the infiltration of leukocytes in the ischemic brain by inhibiting the expression of ICAM-1 and VCAM-1.

Ischemic edema can alter the structure and permeability of the blood-brain barrier. Recent studies have reported that progesterone reduces cerebral edema after cerebral ischemia. However, the underlying mechanism of this effect has not yet been elucidated. In the present study, progesterone effectively reduced Evans blue extravasation in the ischemic penumbra, but not in the ischemic core, 48 hours after cerebral ischemia in rats. Progesterone also inhibited the down-regulation of gene and protein levels of occludin and zonula occludens-1 in the penumbra. These results indicate that progesterone may effectively inhibit the down-regulation of tight junctions, thereby maintaining the integrity of the blood-brain barrier and reducing cerebral edema.