[Exosomes derived from miR-133a-3p engineered mesenchymal stem cells promote myocardial repair in rats after acute myocardial infarction]

Objective: To investigate the effects of exosome derived from miR-133a-3p engineered human umbilical cord blood mesenchymal stem cells (ucMSC) on myocardial repair after acute myocardial infarction (AMI) in rats. Methods: UcMSC was amplified and cultured in vitro. Lentiviral carrying miR-133a-3p and negative control vectors were transfected into ucMSC. Exosomes secreted by the transfected ucMSC were named miR-133a-3p-Exo and miR-NC-Exo, respectively. The AMI model of rats was established by ligation of the left anterior descending coronary artery. MiR-133a-3p-Exo or miR-NC-Exo were then injected into the border zone of the infarct area. Cardiac function was assessed by echocardiography after twenty-eight days of intervention, and Masson staining was used to evaluate the area of myocardial fibrosis post-AMI. The myocardial apoptosis after infarction was evaluated by TUNEL staining and the angiogenesis after infarction was evaluated by immunofluorescence staining in the current study. Results: Compared with the miR-NC-Exo group, the left ventricular ejection fraction in the miR-133a-3p-Exo group was significantly increased ((47.4%±9.8%) vs. (64.2%±8.9%), P<0.05). While the myocardial fibrosis area ((31.2%±7.3%) vs. (18.0%±1.5%), P<0.01) and the percentage of apoptotic cardiomyocytes ((25.6%±3.6%) vs. (15.1%±4.4%), P<0.05) was significantly reduced in the miR-133a-Exo group. Besides, the expression of CD31 and α-smooth muscle actin (α-SMA) were also increased significantly in the miR-133a-3p-Exo group compared to the miR-NC-Exo group (CD31: (2.9±0.9) vs. (13.9±2.0), P<0.000 1, α-SMA: (3.5±0.9) vs. (11.0±1.6), P<0.000 1). Conclusion: Exosome derived from miR-133a-3p engineered ucMSC effectively inhibited myocardial apoptosis and promoted angiogenesis, thus improving the cardiac function after myocardial infarction in rats.

[Comparison of three dimensional CT venography and ascending phlebography based on propensity score matching in the evaluation of recurrent varicose veins]

Objective: To compare the efficacy of lower extremity three dimensional CT venography (CTV) and lower extremity ascending phlebography in evaluating recurrent varicose veins. Methods: A retrospective analysis was conducted on clinical data from 235 patients with unilateral recurrent varicose veins who were treated at the Department of Vascular Surgery,Beijing Shijitan Hospital,Capital Medical University, between January 2015 and December 2020.There were 112 males and 123 females, with an age of (62.5±11.4)years (range:24 to 75 years).Patients were stratified into two groups based on preoperative imaging examination:the CTV group (utilizing lower extremity venous ultrasound+lower extremity CTV) and the control group (employing lower extremity venous ultrasound+lower extremity ascending phlebography).The two groups were matched in a 1∶1 ratio using propensity score matching, resulting in 43 cases per group.Comparative analyses between the groups at the one-year postoperative follow-up were performed using independent sample t tests, Wilcoxon rank-sum tests, χ2 tests, and linear regression analysis. Results: One year post-surgery,the CTV group exhibited a lower venous clinical severity score (VCSS) compared to the control group(M(IQR),3.0(4.3) vs.4.0(5.8),Z=-2.038,P=0.040).Additionally, the chronic venous insufficiency patients' quality of life questionnaire (CIVIQ-20) scores were significantly higher in the CTV group than in the control group (89.0(8.0) vs.82.5(17.0), Z=-2.627, P=0.010).Patients in the CTV group also experienced a shorter ulcer healing time compared to the control group (4.0(4.0) weeks vs.12.0(7.0) weeks, Z=-3.217,P<0.01).Both groups showed no clinically symptomatic recurrent varicose veins or ulcers.However, they exhibited ultrasound-detectable varicose vein recurrence, with no statistically significant difference (χ2=0.453,P=0.500).The number of diseased vessels requiring management based on ultrasound supplemented by CTV was 16, while the number supplemented by ascending phlebography was 7,with a statistically significant difference (χ2=4.800,P=0.030).Linear regression analysis demonstrated that clinical-etiology-anatomy-pathology clinical grading and the preoperative imaging examination method exerted independent influences on VCSS and CIVIQ-20 during the one-year postoperative assessment. Conclusions: CTV-assisted ultrasound enables a direct and comprehensive evaluation and localization of diseased veins in patients with recurrent varicose veins.The utilization of lower extremity vein ultrasound combined with CTV-guided management of lower extremity vessels in minimally invasive treatment significantly improves patient prognosis, surpassing the assessment provided by ascending phlebography.

[Recommendations for diagnosis and treatment of psoriatic arthritis in China]

Psoriatic arthritis is a chronic systemic autoimmune disease, characterized by psoriasis skin lesions and inflammation of the spine and joint. It has complicated clinical manifestations and individual variations. Nearly half of the patients will have joints erosion in two years, which is crippling. The severity of the skin and joint disease frequently do not correlate with each other. Currently, the understanding of the disease is insufficient in China with the lack of standardized diagnosis and treatment. Therefore, researchers from the Chinese Rheumatology Association formulated this specification based on the diagnosis and management experience together with guidelines at home and abroad. The specification summarizes the present situation of domestic diagnosis and treatment, aiming to standardize the diagnosis process and treatment protocols of psoriatic arthritis. Furthermore, it can reduce misdiagnosis and missed diagnosis, as well as improve the prognosis.

[Long-term efficacy of radiofrequency closure in the treatment of great saphenous vein varicose]

Objective: To examine the long-term efficacy of radiofrequency closure in the treatment of great saphenous vein varicose. Methods: The clinic data of 185 patients with varicose veins of lower limbs treated with radiofrequency closure admitted at Department of Vascular Surgery, Beijing Shijitan Hospital, Capital Medical University from July 2016 to January 2017 was analyzed retrospectively. A total of 203 limbs were treated by radiofrequency closure. The long-term efficacy of radiofrequency closure was evaluated by analyzing the closure rate, clinical-etiology- anatomy-pathophysiology (CEAP) grading, venous clinical severity score (VCSS), chronic venous insufficiency questionnaire (CIVIQ) score, and complications, using repeated measures analysis of variance. Results: All procedures were successful. The closure rate was 98.0% (199/203) at one year and two years postoperative, which was still maintained at 97.5% (198/203) at 3 years of follow-up. Postoperative CEAP grading was significantly downgraded compared with that before the operation. Totally 88.4% (76/86) of C5 to C6 grade patients downgraded to C2 to C4 grade at 6 months, and 95.3% (82/86) downgraded to C0 to C2 garde at 3 years postoperative. VCSS and CIVIQ score in both groups significantly improved at all follow-up time points compared to preoperative scores (VCSS: F=1 064.7, P=0.003; CIVIQ score: F=2 984.3, P=0.001). The most common complication was subcutaneous blood stasis (10.8%), most of which disappeared within 1 month after the surgery. Other complications included pigmentation and thrombophlebitis (5.9% and 3.9%, respectively). Conclusion: The long-term efficacy of radiofrequency closure of the great saphenous vein is satisfactory.

Ion irradiation induced strain and structural changes in LiTaO3perovskite

LiTaO₃crystals irradiated with 3 MeV and 1.162 GeV Au ions were studied by single crystal x-ray diffraction and Raman scattering measurements. The maximum lattice strains after 3 MeV Au ion irradiation to a fluence of 1.2 × 10¹³ cm^-2were 1.2% and 0.6% along thec- anda-/b-axes, respectively. Two effects were observed in 1.162 GeV Au ion irradiated samples: (i) the (0006) and (1120) Bragg peaks were split into doublets, which suggested a subtle structural change due to slight modification of chemical composition; and (ii) the pre-damaged 1.2% lattice strain along thec-axis was relaxed to 0.9% after subsequent irradiation with 1.162 GeV Au ions, while relaxation along thea- orb-axis was not obvious. A distinct change in the Raman spectrum of the 〈0001〉 oriented LiTaO₃crystals was observed after 1.162 GeV Au ion irradiation, but no obvious change was observed in the 〈1120〉 oriented samples or in 3 MeV Au ion irradiated samples. Strain and structural changes in crystalline LiTaO₃, with or without pre-existing defects, upon ion irradiation are delineated in its responding to inelastic ionization and elastic nuclear collisions.

Symmetry degeneration and room temperature ferroelectricity in ion-irradiated SrTiO3

Polar phonon modes associated with room temperature ferroelectricity are observed in SrTiO3 single crystals irradiated with Ti ions. Quantitative strain analysis reveals that irradiation-induced out-of-plane strain drives the centrosymmetric cubic SrTiO3 to a tetragonal-like structure in the maximum damaged region. Energy transfer from ions to electrons during ion irradiation yields defects in SrTiO3 that also plays an important role for the room temperature ferroelectricity. Different from thin film techniques, the ferroelectricity in the ion irradiated SrTiO3 can occur for much larger thicknesses, depending on the energy and type of ion.

Variations in aggregate-associated organic carbon and polyester microfibers resulting from polyester microfibers addition in a clayey soil

Organic carbon is an essential element for sustainable soil management. While the effects of microplastics on soil physical and biological properties are presenting, it remains unclear whether the organic carbon dynamics of soil are altered by increased microplastic accumulation. The objectives of this study were to evaluate the influences of different polyester microfiber (PMF 0, 0.1% and 0.3% of soil dry weight) and organic material (OM 0, 1%, 2% and 3% of soil dry weight) addition levels on soil organic carbon and to determine the PMF distribution in aggregates from a pot experiment. After 75 days of incubation under 6 wet-dry cycles, the concentrations of soil total organic carbon did not differ significantly between the PMF (9.7 ± 6.6 g kg^-1) and control (9.7 ± 6.9 g kg^-1) treatments. However, PMF addition significantly reduced the organic carbon concentration in the large (>2 mm) macro-aggregates compared to the control treatment (10.6 ± 4.8 g kg^-1 vs. 11.7 ± 4.4 g kg^-1), but the results were opposite in the small (2-0.25 mm)macro-aggregates (10.2 ± 4.9 g kg^-1 vs. 8.4 ± 3.8 g kg^-1). In this study, less than 30% of added PMFs were incorporated into soil aggregates. In addition, the abundance and average length of aggregate-associated PMF in the large (2210 ± 180 particles per g aggregate and 2.08 ± 0.17 mm) and small (1820 ± 150 particles per g aggregate and 1.68 ± 0.11 mm) macro-aggregates were significantly greater than those in the micro-aggregates (1010 ± 70 particles per g aggregate and 0.72 ± 0.05 mm). Our results demonstrate that the distribution of organic carbon in soil macro-aggregates is affected by PMFs addition. Thus, we propose that the behavior of microplastics inside soil aggregates should be further explored to clarify their effects on the physical protection of soil organic carbon.

Local structure of Ni80X20 (X: Cr, Mn, Pd) solid-solution alloys and its response to ion irradiation

The local structure of Ni₈₀X₂₀ (X: Cr, Mn, Pd) solid-solution alloys was investigated with x-ray absorption and total scattering x-ray diffraction methods. Atomic pair distribution function (PDF) analysis indicated that the local lattice distortion is strongly relevant to the atomic size mismatch, and the local lattice distortion in Ni₈₀Pd₂₀ alloy is obviously larger than that in other solid-solution alloys. The bond length of different atomic pairs was derived from the fitting of extended x-ray absorption fine structure spectra. Quantitative analysis of the local bonding environment in Ni₈₀Cr₂₀ during Ni ion irradiation suggested that Cr atoms tend to form clusters in Ni₈₀Cr₂₀ with the increase of ion dose.

Effects of polyester microfibers on soil physical properties: Perception from a field and a pot experiment

Understanding soil physical properties is essential for soil quality management and sustainable land use. With the growing accumulation of microplastics in soils, a better understanding of the impact of microplastics on soil physical properties is crucial to conserve and manage soil quality. This study explored the effects of polyester microfiber (PMF) concentrations (0, 0.1% and 0.3%) on bulk density, porosity, aggregation and hydraulic conductivity of a clayey soil from a field experiment (1 year) and a pot experiment (6 wet-dry cycles). Polyester microfibers significantly increased the volume of >30 μm pores and reduced the volume of <30 μm pores compared to the control treatment. However, there were no detectable changes in the soil bulk density and saturated hydraulic conductivity between the PMF treatments and the control treatment. Interestingly, we observed that polyester microfibers significantly increased the contents of water stable large macroaggregates (>2 mm) in the 0.3% PMF (44%) and 0.1% PMF (39%) treatments compared to the control treatment (31%) in the pot experiment, but this was not true in the field experiment. The efficient interaction between polyester microfibers and fine soil particles and the frequent wet-dry cycles enhanced the formation and stability of macro-aggregates induced by polyester microfibers in the pot experiment. Overall, our results provide valuable evidence for microplastic influences on soil physical properties. Because microplastics are long-term anthropogenic contaminants, it is necessary to further study the impacts of microplastics on soil quality for terrestrial ecosystem sustainability.

Polygraph Accuracy of Control Question Test in Criminal Cases

Objective To explore polygraph accuracy of Control Question Test （CQT）and whether it could be influenced by examinee's education level and type of violation of law. Methods Real cases of CQT （n=104） and the data from MAO （n=296） were collected. The polygraph accuracy of CQT was calculated. Variance analysis on three groups of different education levels was used to compare their age, and then the chi-square test was employed to compare polygraph accuracy among the groups. Independent sample t test was used to compare the age of subjects in the two groups of different types of violation of law, and then chi-square test was used to compare the true positive rate and true negative rate of lie detection after integration. Results In CQT lie detection of criminal cases, the true positive rate was 87.00%, the false negative rate was 13.00%, the true negative rate was 82.20%, and the false positive rate was 17.80%. There was no statistical significance in the differences between the true positive rate and the true negative rate （P>0.05）. In CQT lie detection of the groups of different education levels, there was no statistical significance in the differences between the true positive rates （P>0.05） while the differences between the true negative rates had statistical significance （P<0.05）. There was no statistical significance in the differences of both the true positive rates and the true negative rates between the violent violation of law and non-violent violation of law （P>0.05）. Conclusion There is no significant difference between the efficiency of CQT lie detection of identifying criminals and excluding innocents. However, a comparatively high false positive rate and false negative rate still exist. The efficiency of CQT lie detection identifying criminals may not influenced by the examinee's education level and type of violation of law, but its efficiency of excluding innocents may be influenced by the examinee's education level.

Anesthetic management for cesarean delivery in a patient with uncorrected pulmonary atresia, ventricular septal defect and major aortopulmonary collateral arteries

Pulmonary atresia witha ventricular septal defect and major aortopulmonary collateral arteries is an extremely rare congenital disorder characterized by a high risk of maternal mortality. We present the case of a 24-year-old primigravid woman with uncorrected pulmonary atresia, ventricular septal defect and major aortopulmonary collateral arterieswho presented at 35+5 weeks' gestation. Based on the pathophysiology of the congenital cardiac lesion, cesarean delivery was performed under epidural anesthesia under management by a multidisciplinary team. This report highlights the anesthesia management of a rare uncorrected congenital cardiac lesion for cesarean delivery.

[Validation of the Caprini risk assessment model for venous thromboembolism in Chinese hospitalized patients in a general hospital]

Objective: To assess the validity of Caprini risk assessment model in prediction of venous thromboembolism in Chinese hospitalized patients in a general hospital. Methods: Medical record review was performed in Beijing Shijitan Hosital for all eligible hospitalized patients who underwent screening for venous thromboembolism between January and December 2015. The Caprini score of patients with or without venous thromboemboilism and incidence of venous thromboembolism in patients with various Caprini risk levels, surgery and medical patients was compared. Results: A total of 6 966 inpatients were enrolled. Three hundred and ninety-six patients developed venous thromboembolism. The Caprini median score of patients with venous thromboemboilism was 5 (3-7), which higher than 3(2-5) of patients without venous thromboembolism(Z=-13.68, P<0.01). Incidence of venous thromboembolism of patients in low, moderate, high, highest risk level was 1.0%, 1.8%, 5.7%, 10.6%, respectively. There was no statistically significant difference of incidence between low and moderate risk patients (OR=1.88, 95%CI: 0.89-3.99, P>0.05), but significant difference between moderate and high risk (OR=3.23, 95%CI: 2.06-5.06, P<0.01), high and highest risk patients (OR=1.97, 95%CI: 1.59-2.45, P<0.01). There was no incidence difference of venous thromboembolism between surgery and medical patients in the same Caprini level of low (χ(2)=3.58 , P>0.05), moderate(χ(2)=2.89, P>0.05), high(χ(2)=0.46, P>0.05), highest risk(χ(2)=1.61, P>0.05). Conclusion: Caprini risk assessment model can effectively predict the occurence of venous thromboembolism in Chinese hospitalized patients with high risk of VTE(Caprini score >2)in a general hospital.

Local structure and defects in ion irradiated KTaO3

The modification of the local structure in cubic perovskite KTaO₃ irradiated with 3 MeV and 1.1 GeV Au ions is studied by Raman and x-ray absorption spectroscopy, complemented by density functional theory (DFT) calculations. In the case of irradiation with 3 MeV Au ions where displacement cascade processes are dominant, the Ta L₃-edge x-ray absorption measurements suggest that a peak corresponding to the Ta-O bonds in the TaO₆ octahedra splits, which is attributed to the formation of Ta_K antisite defects that are coupled with oxygen vacancies, V _O. This finding is consistent with the DFT calculations. Under irradiation with 1.1 GeV ions, the intense ionization and electronic energy deposition lead to a blue shift and an intensity reduction of active Raman bands. In the case of sequential irradiations, extended x-ray absorption fine structure measurements reveal a decrease in concentration of coupled Ta_K-V _O defects under subsequent irradiation with 1.1 GeV Au ions.

Local Structure and Short-Range Order in a NiCoCr Solid Solution Alloy

Multielement solid solution alloys are intrinsically disordered on the atomic scale, and many of their advanced properties originate from the local structural characteristics. The local structure of a NiCoCr solid solution alloy is measured with x-ray or neutron total scattering and extended x-ray absorption fine structure (EXAFS) techniques. The atomic pair distribution function analysis does not exhibit an observable structural distortion. However, an EXAFS analysis suggests that the Cr atoms are favorably bonded with Ni and Co in the solid solution alloys. This short-range order (SRO) may make an important contribution to the low values of the electrical and thermal conductivities of the Cr-alloyed solid solutions. In addition, an EXAFS analysis of Ni ion irradiated samples reveals that the degree of SRO in NiCoCr alloys is enhanced after irradiation.

Chronic alcohol administration affects purine nucleotide catabolism in vivo

AIMS

To investigate the relationship between chronic alcohol administration and purine nucleotide metabolism in vivo.

MAIN METHODS

Rat models of alcohol dependence and withdrawal were used. The concentrations of uric acid (UAC), urea nitrogen (UREA), creatinine (CREA), and beta-2-microglobulin (β2-M) and creatinine clearance rate (CCR) in plasma were measured. The PLC method was used to detect the absolute content of purine nucleotides in different tissues. Enzymatic activities of adenosine deaminase (ADA), xanthine oxidase (XO), ribose 5-phosphate pyrophosphokinase (RPPPK), glutamine phosphoribosylpyrophosphate amidotransferase (GPRPPAT), hypoxanthine-guanine phosphate ribose transferase (HGPRT), and adenine phosphoribosyltransferase (APRT) in the tissues were analyzed. Real-time PCR was used to determine the relative level of ADA and XO.

KEY FINDINGS

The renal function of rats with alcohol dependence was normal. Further, the content of purine nucleotides (GMP, AMP, GTP, and ATP) in tissues of the rats was decreased, which indicated that the increased uric acid should be derived from the decomposition of nucleotides in vivo. The activity of XO and ADA increased, and their mRNA expression was enhanced in the alcohol dependence group, but there was no significant difference in the activity of RPPPK and GPRPPAT in the liver, small intestine, and muscle; furthermore, no significant difference in the activity of HGPRT and APRT was observed in the brain.

SIGNIFICANCE

These results indicate that chronic alcohol administration might enhance the catabolism of purine nucleotides in tissues by inducing gene expression of ADA and XO, leading to elevation of plasma uric acid levels.

Histone H3K9 acetylation influences growth characteristics of goat adipose-derived stem cells in vitro

Adipose-derived stem cells (ADSCs) show nearly unlimited potential in medical and animal science. Currently, understanding of the biological mechanisms regulating ADSC growth in vitro remains very limited. Histone acetylation, an epigenetic modification, plays a key role in maintaining stem cell properties. To further study its effect on ADSC growth characteristics in vitro, we treated goat ADSCs with the histone deacetylase inhibitors trichostatin A (TSA) and vorinostat (SAHA). This inhibited SIRT1 expression and increased histone H3K9 acetylation, leading to decreased cell viability, cell cycle arrest, and apoptosis. Quantitative real-time polymerase chain reaction revealed that H3K9 hyperacetylation stimulated transcription of NANOG, OCT4, SOX2, and TERT, but inhibited that of PCNA, P53, and BAX. Western blotting indicated that TSA and SAHA increased protein expression of NANOG, reduced that of SOX2, TERT, PCNA, P53, and BAX, and did not change that of OCT4. These findings provide new experimental evidence contributing to our understanding of the mechanisms underlying ADSC growth characteristics in vitro.

Pressure-induced phase transitions of β-type pyrochlore CsTaWO6

The β-type pyrochlore CsTaWO₆ was studied by synchrotron X-ray diffraction (XRD) and Raman scattering methods up to pressures of 43 GPa using a diamond anvil cell (DAC).

Pressure-induced disordering and anomalous lattice expansion in La2Zr2O7 pyrochlore

Pressure-induced cation and anion disordering in La2Zr2O7 pyrochlore is quantitatively analyzed by Rietveld refinement of in situ x-ray diffraction patterns, Raman, and infrared measurements. An anomalous lattice expansion and obvious change of the pressure dependence of the vibrational modes occur at ∼10  GPa. The pressure-induced water incorporation in the La2Zr2O7 pyrochlore structure may be related to a previously noted photoelectrochemical effect.

Phase stability and pressure dependence of defect formation in Gd2Ti2O7 and Gd2Zr2O7 pyrochlores

We report dramatically different behaviors between isostructural Gd2Ti2O7 and Gd2Zr2O7 pyrochlore at pressures up to 44 GPa, in which the substitution of Ti for Zr significantly increases structural stability. Upon release of pressure, the Gd2Ti2O7 becomes amorphous. In contrast, the high-pressure phase of Gd2Zr2O7 transforms to a disordered defect-fluorite structure. First-principle calculations for both compositions revealed that the response of pyrochlore to high pressure is controlled by the intrinsic energetics of defect formation.

Tyrosine kinase receptor immunoreactivity in trigeminal mesencephalic and motor neurons following transection of masseteric nerve of the rat

Neurotrophins are known to promote survival after neural injury. To determine the relative importance of tyrosine kinase receptors on the survival of axotomized trigeminal nuclear neurons, we examined the temporal expression profile of tyrosine kinase A, tyrosine kinase B and tyrosine kinase C receptors in the mesencephalic trigeminal nucleus and the motor trigeminal nucleus following transection of the masseteric nerve in rats. Axotomized neurons in these nuclei were retrogradely identified with FluoroGold. We found increase in tyrosine kinase A-immunoreactive mesencephalic trigeminal nucleus neurons in the second week after axotomy but no change in the number of tyrosine kinase A-immunoreactive motor trigeminal nucleus neurons. There was no change in the number of tyrosine kinase B-immunoreactive mesencephalic trigeminal nucleus neurons but the significant increase of tyrosine kinase B-immunoreactive motor trigeminal nucleus neurons throughout the period of observation (3 weeks) peaked at approximately 1 week after axotomy. There was no alteration in the number of tyrosine kinase C-immunoreactive mesencephalic trigeminal nucleus neurons but significant increase in tyrosine kinase C-immunoreactive motor trigeminal nucleus neurons observable by 4 days post-axotomy was followed by decline to levels lower than the control in 2 weeks. Temporal changes in the expression of individual tyrosine kinase receptors in mesencephalic trigeminal nucleus and motor trigeminal nucleus neurons following transection of the masseteric nerve suggest differential contribution of tyrosine kinase-specific neurotrophins to the survival of these neurons after axotomy.

Expression of Trk receptors in otolith-related neurons in the vestibular nucleus of rats

The expression of the three Trk receptors (TrkA, TrkB, and TrkC) in otolith-related neurons within the vestibular nuclei of adult Sprague-Dawley rats was examined immunohistochemically. Conscious animals were subjected to sinusoidal linear acceleration along either the anterior-posterior (AP) or interaural (IA) axis on the horizontal plane. Neuronal activation was defined by Fos expression in cell nuclei. Control animals, viz labyrinthectomized rats subjected to stimulation and normal rats that remained stationary, showed only a few sporadically scattered Fos-labeled neurons. Among experimental rats, the number of Fos-labeled neurons and their distribution pattern in each vestibular subnucleus in animals stimulated along the antero-posterior axis were similar to those along the interaural axis. No apparent topography was observed among neurons activated along these two directions. Only about one-third of the Trk-immunoreactive neurons in the vestibular nucleus expressed Fos. Double-labeled Fos/TrkA, Fos/TrkB and Fos/TrkC neurons constituted 85-98% of the total number of Fos-labeled neurons in vestibular nuclear complex and its subgroups x and y. Our findings suggest that Trk receptors and their cognate neurotrophins in central otolith neurons may contribute to the modulation of gravity-related spatial information during horizontal head movements.

Morphine alleviates early stages of apoptosis in cultured CEM x174 cells infected with simian immunodeficiency virus

The reduction in apoptosis caused by short-term exposure of CEM x174 cells infected with SIVmac239 to morphine was investigated. Eeffects of morphine on the viability of normal and infected CEM x174 cells were determined by MTS assay. Apoptosis induced by SIVmac239 and the effects of morphine were analyzed by flow cytometry. cAMP levels, PKA activity, and the resulting histone H3 phosphorylation levels were measured. The results show a pronounced decrease in numbers of infected SIVmac239 cells compared to controls. Morphine elevated cell viability in the infected groups. Annexin V binding assays showed that 1 microM l(-1) morphine increased the percentage of viable cells and decreased apoptotic cells. Morphine also downregulated cAMP and PKA activity in both groups, but more markedly in the infected group. Histone H3 phosphorylation was elevated after virus infection and decreased in the presence of morphine. The results indicate that the cAMP-PKA signal transduction cascade is involved in morphine regulation of early SIVmac239-induced apoptosis.

Morphine alleviates early stages of apoptosis in cultured CEM x174 cells infected with simian immunodeficiency virus

The reduction in apoptosis caused by short-term exposure of CEM x174 cells infected with SIVmac239 to morphine was investigated. Eeffects of morphine on the viability of normal and infected CEM x174 cells were determined by MTS assay. Apoptosis induced by SIVmac239 and the effects of morphine were analyzed by flow cytometry. cAMP levels, PKA activity, and the resulting histone H3 phosphorylation levels were measured. The results show a pronounced decrease in numbers of infected SIVmac239 cells compared to controls. Morphine elevated cell viability in the infected groups. Annexin V binding assays showed that 1 microM l(-1) morphine increased the percentage of viable cells and decreased apoptotic cells. Morphine also downregulated cAMP and PKA activity in both groups, but more markedly in the infected group. Histone H3 phosphorylation was elevated after virus infection and decreased in the presence of morphine. The results indicate that the cAMP-PKA signal transduction cascade is involved in morphine regulation of early SIVmac239-induced apoptosis.

Receptors of glutamate and neurotrophin in vestibular neuronal functions

The last decade has witnessed advances in understanding the roles of receptors of neurotrophin and glutamate in the vestibular system. In the first section of this review, the biological actions of neurotrophins and their receptors in the peripheral and central vestibular systems are summarized. Emphasis will be placed on the roles of neurotrophins in developmental plasticity and in the maintenance of vestibular function in the adult animal. This is reviewed in relation to the developmental expression pattern of neurotrophins and their receptors within the vestibular nuclei. The second part is focused on the functional role of different glutamate receptors on central vestibular neurons. The developmental expression pattern of glutamate receptor subunits within the vestibular nuclei is reviewed in relation to the potential role of glutamate receptors in regulating the development of vestibular function.

Neurotrophin receptor immunostaining in the vestibular nuclei of rats

The distribution of high-affinity neurotrophin receptors in cells of the vestibular nuclear complex and its subnuclei of adult rats was examined. We noted a high density of tyrosine kinase (Trk) A- and B- and a lower density of TrkC-immunostained cells. In particular, long, intensely labelled immunostained-TrkB fibres formed networks in the neuropil. Both TrkA- and TrkB-immunostained cells were widely distributed in the lateral, medial and spinal vestibular nuclei, and were less frequently seen in the superior vestibular nucleus, x and y subnuclei. However, immunostaining for TrkC was weak in many cells within the vestibular nuclei. The widespread and abundant neuronal distribution of Trk receptors predicts that their associated neurotrophins exert significant effects on individual cells within the vestibular nuclei.

Bacterial lipopolysaccharide activates NF-kappaB through toll-like receptor 4 (TLR-4) in cultured human dermal endothelial cells. Differential expression of TLR-4 and TLR-2 in endothelial cells

A missense mutation in the cytoplasmic domain of the Toll-like receptor-4 (TLR-4) has been identified as the defect responsible for lipopolysaccharide (LPS) hyporesponsiveness in C3H/HeJ mice. TLR-4 and TLR-2 have recently been implicated in LPS signaling in studies where these receptors were overexpressed in LPS non-responsive 293 human embryonic kidney cells. However, the signaling role of TLR-4 or TLR-2 in human cells with natural LPS response remains largely undefined. Here we show that human dermal microvessel endothelial cells (HMEC) and human umbilical vein endothelial cells express predominantly TLR-4 but very weak TLR-2 and respond vigorously to LPS but not to Mycobacterium tuberculosis 19-kDa lipoprotein. Transient transfection of non-signaling mutant forms of TLR-4 and anti-TLR-4 monoclonal antibody inhibited LPS-induced NF-kappaB activation in HMEC, while a monoclonal antibody against TLR-2 was ineffective. In contrast to LPS responsiveness, the ability of HMEC to respond to 19-kDa lipoprotein correlated with the expression of TLR-2. Transfection of TLR-2 into HMEC conferred responsiveness to 19-kDa lipoprotein. These data indicate that TLR-4 is the LPS signaling receptor in HMEC and that human endothelial cells (EC) express predominantly TLR-4 and weak TLR-2, which may explain why they do not respond to 19-kDa lipoprotein. The differential expression of TLRs on human EC may have important implications in the participation of vascular EC in innate immune defense mechanisms against various infectious pathogens, which may use different TLRs to signal.

Bacterial lipopolysaccharide activates nuclear factor-kappaB through interleukin-1 signaling mediators in cultured human dermal endothelial cells and mononuclear phagocytes

Bacterial lipopolysaccharide (LPS)-mediated immune responses, including activation of monocytes, macrophages, and endothelial cells, play an important role in the pathogenesis of Gram-negative bacteria-induced sepsis syndrome. Activation of NF-kappaB is thought to be required for cytokine release from LPS-responsive cells, a critical step for endotoxic effects. Here we investigated the role and involvement of interleukin-1 (IL-1) and tumor necrosis factor (TNF-alpha) signal transducer molecules in LPS signaling in human dermal microvessel endothelial cells (HDMEC) and THP-1 monocytic cells. LPS stimulation of HDMEC and THP-1 cells initiated an IL-1 receptor-like NF-kappaB signaling cascade. In transient cotransfection experiments, dominant negative mutants of the IL-1 signaling pathway, including MyD88, IRAK, IRAK2, and TRAF6 inhibited both IL-1- and LPS-induced NF-kappaB-luciferase activity. LPS-induced NF-kappaB activation was not inhibited by a dominant negative mutant of TRAF2 that is involved in TNF signaling. LPS-induced activation of NF-kappaB-responsive reporter gene was not inhibited by IL-1 receptor antagonist. TLR2 and TLR4 were expressed on the cell surface of HDMEC and THP-1 cells. These findings suggest that a signal transduction molecule in the LPS receptor complex may belong to the IL-1 receptor/toll-like receptor (TLR) super family, and the LPS signaling cascade uses an analogous molecular framework for signaling as IL-1 in mononuclear phagocytes and endothelial cells.

N-Methyl-D-aspartate inhibits apoptosis through activation of phosphatidylinositol 3-kinase in cerebellar granule neurons. A role for insulin receptor substrate-1 in the neurotrophic action of n-methyl-D-aspartate and its inhibition by ethanol

Primary cultured rat cerebellar granule neurons underwent apoptosis when switched from medium containing 25 mM K+ to one containing 5 mM K+. N-methyl-D-aspartate (NMDA) protected granule neurons from apoptosis in medium containing 5 mM K+. Inhibition of apoptosis by NMDA was blocked by the phosphatidylinositol 3-kinase (PI 3-kinase) inhibitor LY294002, but it was unaffected by the mitogen-activated protein kinase kinase inhibitor PD 98059. The antiapoptotic action of NMDA was associated with an increase in the tyrosine phosphorylation of insulin receptor substrate 1 (IRS-1), an increase in the binding of the regulatory subunit of PI 3-kinase to IRS-1, and a stimulation of PI 3-kinase activity. In the absence of extracellular Ca2+, NMDA was unable to prevent apoptosis or to phosphorylate IRS-1 and activate PI 3-kinase. Significant inhibition of NMDA-mediated neuronal survival by ethanol (10-15%) was observed at 1 mM, and inhibition was half-maximal at 45-50 mM. Inhibition of neuronal survival by ethanol corresponded with a marked reduction in the capacity of NMDA to increase the concentration of intracellular Ca2+, phosphorylate IRS-1, and activate PI 3-kinase. These data demonstrate that the neurotrophic action of NMDA and its inhibition by ethanol are mediated by alterations in the activity of a PI 3-kinase-dependent antiapoptotic signaling pathway.

Ethanol induces apoptosis in cerebellar granule neurons by inhibiting insulin-like growth factor 1 signaling

The ability of ethanol to interfere with insulin-like growth factor 1 (IGF-1)-mediated cell survival was examined in primary cultured cerebellar granule neurons. Cells underwent apoptosis when switched from medium containing 25 mM K+ to one containing 5 mM K+. IGF-1 protected granule neurons from apoptosis in medium containing 5 mM K+. Ethanol inhibited IGF-1-mediated neuronal survival but did not inhibit IGF-1 receptor binding or the neurotrophic action of elevated K+, and failed to potentiate cell death in the presence of 5 mM K+. Inhibition of neuronal survival by ethanol was not reversed by increasing the concentration of IGF-1. Significant inhibition by ethanol (15-20%) was observed at 1 mM and was half-maximal at 45 mM. The inhibition of IGF-1 protection by ethanol corresponded to a marked reduction in the phosphorylation of insulin receptor substrate 1, the binding of phosphatidylinositol 3-kinase (PI 3-kinase), and a block of IGF-1-stimulated PI 3-kinase activity. The neurotrophic response of IGF-1 was also inhibited by the PI 3-kinase inhibitor LY294002, the protein kinase C inhibitor chelerythrine chloride, and the protein kinase A inhibitor KT5720, but unaffected by the mitogen-activated protein kinase kinase inhibitor PD 98059. These data demonstrate that ethanol promotes cell death in cerebellar granule neurons by inhibiting the antiapoptotic action of IGF-1.

Protein phosphorylation in response to PDGF stimulation in cultured neurons and astrocytes

Platelet-derived growth factor (PDGF) is an important growth factor for a variety of cells, including neurons and glial cells. PDGF signal transduction pathways have been studied primarily in mesenchyme-derived cells (such as fibroblasts and smooth muscle cells). However, little is known about these pathways in the central nervous system (CNS). It is believed that phosphorylation is a critical aspect of several steps in the signal transduction pathway. In this study, neurons and type 1 astrocytes in vitro were radiolabeled with 32P-orthophosphate (32P-Pi). The cells were lysed, and labeled proteins were separated by two-dimensional gel electrophoresis. Autoradiograms of PDGF-stimulated and control samples were compared. We found that in neurons and type 1 astrocytes in vitro, PDGF-BB greatly enhances protein phosphorylation while PDGF-AA has less of an effect on protein phosphorylation. Furthermore, because PDGF signal transduction pathways are likely to affect the cytoskeleton, we studied changes in actin-binding proteins induced by PDGF-BB. We found that PDGF-BB alters the expression, migration pattern and/or avidity of some actin-binding proteins in neurons. In conclusion, protein phosphorylation is up-regulated by PDGF in mouse cortical neurons and type 1 astrocytes in vitro. PDGF's effects on phosphorylation of cytoskeletal proteins might be a important mechanism by which PDGF affects the development and normal functions of central nervous system cells.

Expression of platelet-derived growth factor (PDGF) receptor alpha-subunit in mouse brain: comparison of Patch mutants and normal littermates

1. Platelet-derived growth factor (PDGF) plays an important role not only in mesenchyme-derived tissues, but also in the mammalian central nervous system. The Patch mutant (Ph/+) lacks one copy of the PDGFR-alpha gene. However, it is not clear whether there are differences in expression of PDGF receptor alpha-subunit (PDGFR-alpha) in brain tissue of the Patch heterozygous (Ph/+) mutants compared to wild-type C57Bl (+/+) mice. 2. The level of PDGRF-alpha mRNA expression is slightly lower in Patch mutant than in normal littermate. 3. Protein and total RNA isolated from mouse brain tissue and primary type 1 astrocyte cultures were studied with Western and Northern blotting techniques. There was no measurable difference ir PDGFR-alpha protein expression between the Patch and wild-type mouse nervous system. Adjustment of transcriptional efficiency and messenger stability may contribute to this phenomenon, whose biological significance remains unclear. 4. Further, the expression of PDGRF-alpha protein and message in mouse brain tissues is developmentally regulated. Its level remains high during the embryonic period and declines below measurable levels in adult.

Phosphorylation of F1F0 ATPase delta-subunit is regulated by platelet-derived growth factor in mouse cortical neurons in vitro

The delta subunit of F1F0 ATPase (ATP synthase complex) is part of the stalk connecting the F1 and F0 moieties. Studies in Escherichia coli suggest that the analogous bacterial subunit, called epsilon, is essential for the ATPase assembly energy coupling. Platelet-derived growth factor (PDGF) is an important growth factor for various cell types, including neurons of the CNS. Using two-dimensional gel electrophoresis, microsequencing, western blot analysis, and immunoprecipitation techniques, we have found that PDGF induces phosphorylation of the delta subunit or a closely related peptide in cultured mouse cortical neurons.