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The multiferroic Y-type hexaferrites BaxSr2−xMe2Fe12−yAlyO22 (Me = Zn2+, Co2+, Mg2+, etc.) have attracted much attention due to their giant magnetoelectric (ME) effect up to room temperature and low modulated magnetic field by the chemical doping control of the complex magnetic phases. However, the research of substitution between the Me ions is rare. As doping at the Me ion site can combine the advantages of both, e.g., higher magnetic ordering temperature in Co2 and stronger ME coefficient in Mg2 Y-type hexaferrites, herein, we report the stability and switching of magnetoelectric states in the Y-type hexaferrites Ba0.5Sr1.5CoMgFe11AlO22 single crystals. Our results demonstrate that substituting half of the Mg2+ with Co2+ enhances the transition temperature of the alternating longitudinal conical phase to proper screw spin order up to room temperature compared to those Mg2 Y-type hexaferrites. Simultaneous occurrence of in-plane and out-of-plane ferroelectric polarization is observed, alongside comparable spontaneous magnetization. It was found that the in-plane spin-driven polarization can be reversible below 50 K with a substantial ME coefficient α = −8000 ps/m but becomes irreversible at 100 K. This reversal in the sign of the ME coefficient signifies the transition between two distinct ME states at high temperature. The reversibility and irreversibility of spin-induced polarization are discussed within the framework of free energy based on the ferroelectric phase, which prevail in numerous Y-type hexaferrites. Our results provide insights into understanding the role of the Me ions in the magnetoelectric coupling in Y-type hexaferrites. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To explore the effect of miR-30a-3p on osteoporosis in rats after ovariectomy. MATERIALS AND METHODS: The ovariectomized (OVX) rat model was established to mimic postmenopausal osteoporosis. The primary bone marrow mesenchymal stem cells (BMMSCs) isolated from female rats were transfected with mimic or inhibitor. Real Time Reverse Transcription-Polymerase Chain Reaction (RT-PCR) and Western blotting were used to examine the expressions of miR-30a-3p and osteoporosis-related proteins. The bone mineral density (BMD) was detected via micro-Computed Tomography (CT) and the bone histomorphometry was performed. Luciferase assay was also performed to confirm whether SFRP1 is a target of miR-30a-3p. RESULTS: According to micro CT, BMD significantly declined in OVX group. MiR-30a-3p and SFRP1 were negatively correlated after ovariectomy. SFRP1 was acknowledged as a target of miR-30a-3p. Besides, the miR-30a-3p inhibitor promoted osteogenic differentiation in vitro and bone formation in vivo. CONCLUSIONS: MiR-30a-3p inhibitor promotes bone formation through decreasing SFRP1 expression and miR-30a-3p may be a potential novel molecular target in the treatment of osteoporosis. [ABSTRACT FROM AUTHOR]

The multiferroic Y-type hexaferrites BaxSr2−xMe2Fe12−yAlyO22 (Me = Zn2+, Co2+, Mg2+, etc.) have attracted much attention due to their giant magnetoelectric (ME) effect up to room temperature and low modulated magnetic field by the chemical doping control of the complex magnetic phases. However, the research of substitution between the Me ions is rare. As doping at the Me ion site can combine the advantages of both, e.g., higher magnetic ordering temperature in Co2 and stronger ME coefficient in Mg2 Y-type hexaferrites, herein, we report the stability and switching of magnetoelectric states in the Y-type hexaferrites Ba0.5Sr1.5CoMgFe11AlO22 single crystals. Our results demonstrate that substituting half of the Mg2+ with Co2+ enhances the transition temperature of the alternating longitudinal conical phase to proper screw spin order up to room temperature compared to those Mg2 Y-type hexaferrites. Simultaneous occurrence of in-plane and out-of-plane ferroelectric polarization is observed, alongside comparable spontaneous magnetization. It was found that the in-plane spin-driven polarization can be reversible below 50 K with a substantial ME coefficient α = −8000 ps/m but becomes irreversible at 100 K. This reversal in the sign of the ME coefficient signifies the transition between two distinct ME states at high temperature. The reversibility and irreversibility of spin-induced polarization are discussed within the framework of free energy based on the ferroelectric phase, which prevail in numerous Y-type hexaferrites. Our results provide insights into understanding the role of the Me ions in the magnetoelectric coupling in Y-type hexaferrites. [ABSTRACT FROM AUTHOR]

To compensate for the poor quality of thick-plate blanking parts in cross-section, this paper suggests using the optimizing bilateral ring gear holder parameters to increase burnish zone and improve cutting precision. With the bilateral gear ring, the hydrostatic pressure of shear deformation zone will increase, plasticity of the material will be lifted to maximum and quality of the cross section will be raised. This paper establishes 8mm AISI-1020 fine blanking model by DEFORM2D, analysis different ring gear parameters and clearance that are influenced the stress-strain and cross section quality to predict forming defects. By using the bilateral gear ring blank holder, the poor quality of thick-plate blanking section is successfully enhanced. Therefore, the bilateral gear ring blank holder is vital to improve the quality of blanking parts and provide the reliable theory basis for the practical engineering application. [ABSTRACT FROM AUTHOR]

The present study was performed to investigate the effects of a commercially available probiotic product (compound probiotic) containing Bacillus subtilis 7.0 × 109 CFU g−1, Bacillus licheniformis 3.0 × 109 CFU g−1, Lactobacillus spp. 5.0 × 108 CFU g−1 and Arthrobacter spp. 1.0 × 108 CFU g−1 on the growth performance, non-specific immunity and protection against Vibrio harveyi infection in cobia ( Rachycentron canadum). Fish were fed diets containing six graded levels of compound probiotic (0.0, 1.0, 2.0, 3.0, 4.0 and 5.0 g kg−1) for 8 weeks. The results showed that the survival rate ranged from 81.1% to 84.4% with no significant difference among dietary treatments ( P > 0.05) after feeding experiment. Dietary compound probiotic significantly increased the specific growth rate (SGR), serum lysozyme, alternative complement pathway (ACP) activity, phagocytosis percentage (PP) and respiratory burst activity of head-kidney macrophages of cobia. Moreover, feeding of supplemented diets containing compound probiotic resulted in significantly lower mortality against the pathogens Vibrio harveyi compared with the control group. To elevate the growth and immune resistance ability of cobia, an optimal dose of dietary compound probiotic administration determined by second-order polynomial regression analysis was 3.3 g kg−1, on the basis of the SGR and mortality after challenge with V. harveyi. [ABSTRACT FROM AUTHOR]

When deep drawing rectangle parts, instead of adopting elastic or several segmented blank holders, a new thought of applying dual layers of blank holders, which are parallel to each other, has been achieved to asynchronously vary blank holder force (BHF) at different regions of sheet flange, by dint of replacing different little mandrils in length between dual layers of blank holders, thus to further improve the formability of products. At the same time, in order to solve two problems of how to judge which one distribution of one desired integral variable BHF, which was obtained from the thickness analyses with products in advance, on blank holder for asymmetric parts is the best and to evaluate lubricant in deep drawing, a probe sensor with structure of dual cantalevers, based on the theory of resistance strain slice, fixed into the inner space of die, was developed for measuring real-time friction coefficient of sheet flange’s surface. Through this special probe sensor, not only real-time BHF on sheet flange could be measured out, but also the real-time friction coefficient could be figured out. Finally, one example of rectangle part was carried out in tests to validate the feasibility of this thought. By the way of analyzing the distribution of variation with products’ thickness on products and judging whether the whole distribution of friction on sheet flange’s surface was uniform or not, one optimized BHF loading profile could be finally obtained over the whole punch stroke. [ABSTRACT FROM AUTHOR]

Variations in tensile yield strength of annealed CuAl7 copper alloy were investigated. Both grain and feature size effects could be observed. Statistical analysis revealed that the grain size effect was greater than the feature size effect. The grain size effect on the tensile yield strength of the alloy was very significant. The feature size effect was very significant or significant when the specimen thickness was no more than 0.50 mm, while the effect was insignificant or completely absent when the specimen thickness was greater than 0.50 mm. In addition to grain size d and specimen thickness t, the t/d ratio of the specimen can also affect the tensile yield strength. The tensile yield strength of the alloy was almost a constant when the t/d ratio was greater than a critical value (approximately 21). Otherwise, the strength tended to increase with an increasing value of t/d, except for the specimen with a thickness of 0.25 mm. The size effects on the tensile strength of the CuAl7 copper alloy were compared with the effects on the compression strength. It was found that the size effect intensity on the compression yield strength was greater than that on the tensile yield strength. [ABSTRACT FROM AUTHOR]

Objective: To analyze the dietary patterns of Chinese adults and explore the relationship with serum uric acid (SUA) and hyperuricemia (HUA). Methods: A total of 9 358 adults were selected in the 2018 China Health and Nutrition Survey. Dietary intake data were collected by three consecutive 24-hour dietary recalls and weighing method. The social demographic information of the survey subjects was obtained through questionnaire surveys. The dietary patterns were extracted using factor analysis, and the relationship between dietary patterns and SUA was analyzed using multiple linear regression analysis. The correlation between HUA and dietary patterns was analyzed using logistic regression analysis models. Results: Four dietary patterns were identified: northern (high intakes of wheat, other cereals,and tubers); modern (high intakes of fruit, dairy, eggs, and nuts); southern (high intakes of rice and vegetables);animal food-wine (high intake of organ meats, seafood, and wine). The multiple linear regression analysis results showed that the northern pattern was negatively correlated with SUA ( β =-0.438, 95% CI : -0.500--0.376); the modern pattern was negatively correlated with SUA ( β =-0.134, 95% CI : -0.219--0.049); the southern model was significantly correlated with higher SUA ( β =0.146, 95% CI : 0.079-0.214); the animal food-wine pattern was positively correlated with SUA ( β =0.188, 95% CI : 0.123-0.252). Logistic regression analysis showed that compared with the northern model score Q 1 group, the risk of developing HUA was reduced in Q 3 and Q 4 groups, with OR s values of 0.777 (95% CI : 0.650-0.929) and 0.509 (95% CI : 0.423-0.613), respectively; and compared with the modern model score Q 1 group, the higher the scores in Q 3 and Q 4 groups, the HUA was lower, with OR s of 0.793 (95% CI : 0.660-0.953) and 0.768 (95% CI : 0.631-0.934), respectively. Compared with the animal food-wine pattern score Q 1 group, the risk of developing HUA was increased in both Q 3 and Q 4 groups ( Q 3 group: OR =1.224, 95% CI : 1.012-1.480; Q 4 group: OR =1.312, 95% CI : 1.086-1.584). Conclusions: Dietary patterns are associated with HUA. The northern and modern patterns are related to lower SUA levels and reduced risk of HUA, while the animal food-wine pattern increases the risk of HUA.

Objective: To analyse the clinical characteristics of patients with acute intermittent porphyria (AIP) in order to improve the understanding and treatment. Methods: Patients diagnosed as AIP and admitted to the First Affiliated Hospital of Zhengzhou University were retrospectively enrolled from January 2008 to July 2018. Data of clinical manifestations, causes, laboratory data, treatment and clinical outcome were recorded. Results: Among the 50 patients, 41 patients (82%) were aged 20 to 40. The ratio of male and female was 1∶1.8. The most common symptoms were abdominal pain (94.0%), nausea, vomiting (72.0%) and constipation (42.0%). Neuropsychiatric disorders were seen in 72.0% patients, and 30.0% of the patients had dark-coloured urine. Precipitating factors included infections, menstruation, starvation, drugs, alcohol consumption, mental stimulation and so on. Laboratory tests were abnormal for urinary porphobilinogen, liver function, hyponatremia, anaemia and so on. Various mutations of hydroxymethylbilane synthase (HMBS) genes were detected in 16 patients. Management strategies included removal of risk factors, administration of glycogen and symptomatic treatment during acute episode. Most patients were discharged with improved conditions. Conclusions: The clinical manifestations of acute intermittent porphyria are complex and diverse. Misdiagnoses or malpractice may be fatal. It is critical to emphasize on its early diagnosis and treatment.

Objective: To explore the accuracy of preoperative positioning of neuronavigation and linear measurement localization in the parasagittal meningioma. Methods: Thirty-eight patients with parasagittal meningioma who underwent neurosurgery in the First Affiliated Hospital of Bengbu Medical College from January 2016 to April 2018 were preoperatively positioned with neuronavigation localization and linear measurement localization. The actual position of the tumor was observed during operation, and the accuracy of the two methods was compared. The time taken by the neural navigation positioning and the linear measurement positioning method was recorded, and the difference between the two methods was compared. Results: All cases were treated with neuronavigation and linear measurement, and the tumors were completely exposed after localization. Compared with the actual tumor center position measured during surgery, the average error distance between 38 nerve navigation and actual tumor center position was (2.7±1.9) mm, and the average error distance between linear measurement and actual tumor center position was (3.2±1.3) mm. The difference was not statistically significant, P value=0.207. Neuronavigation includes booting, data import, registration, positioning, etc., which takes an average of (22.3±2.3) minutes. The linear positioning method included image data measurement and localization, and the average time was(1.7±0.3) minutes. The difference between the two groups was statistically significant, and the P value was less than 0.001. Conclusion: The linear measurement localization method and the neuronavigation localization method have good accuracy for preoperative localization of the parasagittal meningioma.

Objective: To compare the clinical effects of modified double-lumen drainage tube and traditional silicone tube in external drainage of chronic subdural hematoma. Methods: Selected 49 patients suffering from chronic subdural hematoma hospitalized in the Department of Neurosurgery, the First Affiliated Hospital of Bengbu Medical College between July 2016 and June 2018 who underwent external drainage, and divided them randomly into experimental groups (using modified brain protection double lumen drainage tube in 23 cases) and control group (using traditional silicone drainage tube in 26 cases). Comparison of postoperative hematoma residual volume, the tube indwelling time, the numbers of drainage tube contact with brain tissue and arachnoid membrane, the numbers of infections, the numbers of postoperative epilepsy cases, and changes in Modified Rankin Scale scores between the two groups. Results: At the time of extubation, the residual amount of hematoma in the experimental group was (13±7) ml, and that in the control group was (17±8) ml. There was no significantly statistical difference in the residual amount of hematoma between the experimental group and the control group ( P >0.05). The tube indwelling time of the experimental group was (2.0±0.9) days, and that of the control group was (2.7±0.8) days. The difference between the experimental group and the control group in the drainage tube indwelling time was statistically significant ( P <0.05). No cases of drainage tube contact with brain tissue and/or arachnoid membrane appeared in the experimental group, and 7 cases of drainage tube contact with brain tissue or arachnoid membrane appeared in the control group. No infection occurred in both groups. No cases of epilepsy occurred in preoperative, and there were 0 cases of epilepsy in the experimental group and 1 case in the control group in postoperative. There were significantly statistical differences in each of the two groups in the modified Rankin scale before and after surgery ( P <0.001), there was no significant difference in postoperative Modified Rankin Scale scores between the two groups. Conclusion: The modified brain protection double-lumen drainage tube has good drainage effect in the external drainage of chronic subdural hematoma, and the short tube retention time, causing fewer complications. It is a safe and effective tool for treating chronic subdural hematoma, and it is worthy of clinical promotion.

Objective: To understand the prevalence of attention deficit and hyperactivity disorder (ADHD) in children in China and provide scientific basis for early prevention and treatment of ADHD in children. Methods: A systematic literature retrieval was conducted by using CNKI, Wanfang data, CBM and VIP databases for the information about the prevalence of ADHD in children in China published from 1979 to 2017. Pubmed database was used to retrieve the literatures about ADHD prevalence in children in China published from 1946 to 2017. The quality of literature was evaluated based on the cross-sectional study criteria according to STROBE statement. Stata 12.0 was used for combined prevalence and subgroup analyses, including gender, regions, publication year, diagnostic criteria, sampling methods, and so on. Egger testing and the evaluation of funnel graph were used to evaluate the publication bias of these literatures, and sensitivity analysis was done by using different models and eliminating the influence of any one of these articles on combined effect value. Results: Twenty articles were included. The total sample size was 88 755, including 46 216 boys and 42 539 girls. The prevalence of ADHD in children in China was 5.6 % (95 %CI : 5.0 % -6.3 % ). The prevalence was 7.7 % (95 %CI : 6.7 % -8.8 % ) in boys and 3.4 % (95 %CI : 3.0 % -3.8 % ) in girls, the difference was statistically significant ( P <0.05). No statistically significance difference in the ADHD prevalence was observed between different regions publication years, diagnostic criteria and sampling methods. Conclusions: The prevalence of ADHD in children in China was high, and boys tended to have a higher prevalence compared with girls. Appropriate screening methods for early detection and intervention conduction of ADHD should be taken among children in China.

Objective: To study the effect of intermittent negative pressure on matrix metalloproteinase 9 (MMP)-9 and transforming growth factor β of tendon-bone interface and joint fluid after reconstruction of anterior cruciate ligament in rabbits. Methods: A total of twenty-four New Zealand white rabbits were randomly selected hind leg of negative group, contralateral hind leg as control.Reconstruction of the anterior cruciate ligament was done by autogenous semitendinosus of rabbit.Joint of the negative pressure side placed drainage tube connecting the micro-negative pressure aspirator, and maintained an intermittent, low-intensity negative pressure.Control side placed ordinary drainage tube.Drainage tube of both sides was pulled out at the same time after 5 days.After 6 weeks, joint fluid and femur-ligament-tibia complex were obtained for study of expression of MMP-9 and TGF-β in joint fluid and tendon-bone interface. Result: Twenty-three rabbits were included in the study because of one rabbit joint infections.Detection of joint fluid showed that MMP-9 content is significantly lower in negative group than that in the control group, and the difference is statistically significant [(8.9±1.3) pg/L vs (12.3±1.8) pg/L ( P =0.002)]. TGF-β content is significantly higher in negative group in joint fluid than that in the control group, and the difference is statistically significant [(19.0±2.2) pg/L vs (15.2±1.4) pg/L ( P =0.000)]. Study of immunohistochemistry in tendon-bone interface found that expression of MMP-9 is lower in negative pressure group than that in the control group, and the difference is statistically significant ( P =0.000). TGF-β expression is significantly higher in negative group in tendon-bone interface than that in the control group, and the difference is statistically significant ( P =0.000). Conclusion: Intermittent negative pressure may reduce content of MMP-9 in joint fluid and expression of MMP-9 in tendon-bone interface, increase content of TGF-β in joint fluid and expression of TGF-β in tendon-bone interface after reconstruction of anterior cruciate ligament in rabbits.

Background: This study was designed to assess the neuroprotective effect of xenon-induced delayed postconditioning on spinal cord ischaemia-reperfusion injury (IRI) and to determine the time of administration for best neuroprotection in a rat model of spinal cord IRI., Methods: Fifty male rats were randomly divided equally into a sham group, control group, and three xenon postconditioning groups (n=10 per group). The control group underwent spinal cord IRI and immediately inhaled 50% nitrogen/50% oxygen for 3 h at the initiation of reperfusion. The three xenon postconditioning groups underwent the same surgical procedure and immediately inhaled 50% xenon/50% oxygen for 3 h at the initiation of reperfusion or 1 and 2 h after reperfusion. The sham operation group underwent the same surgical procedure without aortic occlusion, and inhaled 50% nitrogen/50% oxygen. Neurological function was assessed using the Basso, Beattie, and Bresnahan score at 4, 24, and 48 h of reperfusion. Histological examination was performed using Nissl staining and immunohistochemistry, and apoptosis was detected by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labelling staining., Results: Compared with the control group, the three xenon postconditioning groups showed improvements in neurological outcomes, and had more morphologically normal neurones at 48 h of reperfusion. Apoptotic cell death was reduced and the ratio of Bcl-2/Bax immunoreactivity increased in xenon-treated rats compared with controls., Conclusions: Xenon postconditioning up to 2 h after reperfusion provided protection against spinal cord IRI in rats, but the greatest neuroprotection occurred with administration of xenon for 1 h at reperfusion., (© The Author [2013]. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Vascular endothelial growth factor (VEGF) is an endothelial cell-specific mitogen involved in a number of pathologic processes, including angiogenesis, tumor growth and metastasis. Polymorphisms of the VEGF gene have been associated with susceptibility to colorectal cancer (CRC). However, the specific association still remains controversial. We made a meta-analysis of the association between VEGF gene polymorphisms and CRC risk. Only eight case-control studies were retrieved, with a total of 2337 CRC patients and 2032 healthy controls. Six VEGF gene polymorphisms were addressed in all studies included, +936C>T (rs3025039), -2578C>A (rs699947), -1154G>A (rs1570360), -634G>C (rs2010963), -460C>T (rs833061), and +405C>G (rs2010963). There was a significant association between -2578C>A polymorphism and susceptibility to CRC in the comparison of C allele carriers (CC + CA) versus AA (odds ratio = 0.77, 95% confidence interval = 0.62-0.96, P = 0.02). No association was found between +936C>T, -1154G>A, -634G>C, -460C>T, and +405C>G with susceptibility to CRC. We conclude that the C allele carrier (CC + CA) of VEGF -2578C>A polymorphism appears to be a protective factor for CRC.

Inimicus japonicus, the devil stinger, has an extensive distribution along the coast of China, Japan and the Korean Peninsula. Nineteen highly polymorphic microsatellite markers were isolated and characterized in I. japonicus. Twenty-eight individuals from a wild population were tested for polymorphism using this set of polymorphic microsatellite markers. The number of alleles per locus ranged from 4 to 14. The ranges of observed and expected heterozygosity were 0.500-0.892 and 0.521-0.910, respectively. Significant deviations from Hardy-Weinberg equilibrium were detected at two loci. To the best of our knowledge, these were the first microsatellite loci characterized from the Synanceiidae; they can be used for estimating genetic diversity, population structure studies, parentage analysis, genetic linkage map construction, germplasm classification and identification, gene identification, quantitative trait loci mapping, and marker-assisted selection in breeding of I. japonicus and other species of this family.

Objective: The prevalence of albuminuria and the risk factors associated with albuminuria were evaluated among the Chinese patients diagnosed with type 2 diabetes aged over 30 in the Shanghai downtown. We also evaluated the variability of urinary albumin-to-creatinine ratio (ACR) among the three measurements and the relationship between diabetic retinopathy (DR) and albuminuria., Methods: The 1039 Chinese patients diagnosed with type 2 diabetes aged over 30 were investigated by randomized cluster sampling in the Shanghai downtown and 1018 patients were analyzed in this study. Body mass measurements including height, weight, waist circumference and hip circumference, resting blood pressure, fasting blood measures, urinary ACR and the digitally stored fundus images were investigated. The prevalence of albuminuria was calculated and the risk factors associated with albuminuria were evaluated by stepwise logistic regression. The concordance of urinary ACR was evaluated by observed agreement. The relationship between albuminuria and DR was also evaluated., Results: (1) The mean age of all patients was 66.10+/-11.54 years and the duration of diabetes was 7.89+/-7.16 years. (2) The prevalence of albuminuria was 49.6% among the Chinese patients diagnosed with type 2 diabetes aged over 30 in the Shanghai downtown, 41.4% with microalbuminuria and 8.2% with macroalbuminuria. (3) Microalbuminuria was significantly associated with systolic blood pressure, gender and waist circumference. Macroalbuminuria was significantly associated with systolic blood pressure and duration of diabetes. (4) Observed agreement among the three urinary ACR measurement for albuminuria staging was 73.3% (first versus second), 64.5% (first versus third) and 77.5% (second versus third). Observed agreement in the albuminuria staging between the single urinary ACR measurement and all three urinary ACR measurements was 85.8% (first versus all three), 87.6% (second versus all three) and 81.9% (third versus all three). (5) The percentage of DR in the macroalbuminuric group (59.2%) was significantly higher than that in the normalbuminuria group (16.1%) and microalbuminuria group (24.6%). (6) The macroalbuminuric patients with DR had significantly increased fasting blood glucose and HbA1c compared with the macroalbuminuric patients without DR., Conclusion: The prevalence of microalbuminuria observed in the Chinese patients diagnosed with type 2 diabetes aged over 30 in the Shanghai downtown reached up to 41.4% though the observations in our study might be representative of the diabetic patients of the Shanghai downtown. We agreed that at least two of the three urinary collections were done in a 3- to 6-month period because of the day-to-day variability in albumin excretion. The percentage of DR among the patients with macroalbuminuria was 59.2%, and the macroalbuminuric patients with the significantly high plasma glucose and DR were prone to diagnose DN.

Ouabainlike factor (OLF), assayed as ouabainlike immunoreactivity (OLI), is a probable endogenous digitalislike factor (EDLF). Liquid chromatography/mass spectrometry (LC/MS) is one of the most highly sensitive tools for obtaining structural information regarding low-molecular weight materials in a target compound, and to measure the concentrations of these materials. We have previously reported that OLI can be isolated from the culture supernatant of the rat pheochromocytoma cell line, PC12, by several reverse-phase chromatography and LC/MS techniques. The present study was performed to characterize OLF from biological fluids such as plasma and culture supernatant of PC12 cells by LC/MS. The previous applications of LC/MS to OLI in plasma have been limited to structural identification at the final stages of isolation, in which the starting volume of plasma has been over 10 I. In the present study, we tried to minimize the volume of plasma, and to develop a new preclearing step to gain adequate LC/MS characterization using MS/MS analysis. The plasma was acidified, and OLI was purified by ODS column chromatography. OLI in chromatographic fractions from plasma was assayed by a sensitive enzyme-linked immunosorbent assay for ouabain. After Sep-Pak treatment and two rounds of ODS column chromatography, OLI was identified from 80 ml of plasma. The structure of the purified OLI was identical to authentic ouabain and digoxin, as assessed by LC/MS. In conclusion, we identified the chemically or structurally clarified ouabain and digoxin as the circulating form in plasma by LC/MS.

The present study was undertaken to investigate the changes in renal sympathetic nerve activity (RSNA) and adrenal sympathetic nerve activity (AdSNA) due to acute hemorrhage in anesthetized rabbits. The animals were bled to a mean arterial pressure (MAP) of 5.3 kPa within 10 minutes from the femoral artery. Acute hemorrhage elicited a biphasic responses of RSNA with an initial excitation and a late inhibition during hemorrhage. But hemorrhage only induced a lasting excitation in AdSNA which could be abolished by sino-aortic denervation (SAD). Bilateral vagotomy either before or after hemorrhage could reverse the late inhibition in RSNA, but did not abolish the excitation in AdSNA. Intravenous injection of naloxone or microinjection of naloxone into rostral ventrolateral medulla (RVLM) could reverse the late inhibition in RSNA, but had no significant effect on the initial excitation in RSNA and AdSNA during hemorrhage. Hemorrhage-induced heart (HR) change was similar that in RSNA, but could not be reversed by naloxone. These results indicate that the late inhibition in RSNA is mediated by inputs from vagus nerves and opiate peptide, particularly that in RVLM, and the excitation in AdSNA during hemorrhage is related to arterial baroreceptor reflex.

Rats were bled within 5 min in lowering mean arterial pressure (MAP) to 25 mmHg and were subsequently infused intravenously with hypertonic (7.5% NaCl) or normal saline in a volume equal to 10% of the amount of the lost blood. Intravenous infusion of hypertonic saline significantly facilitated posthemorrhagic recovery of MAP, which was markedly attenuated by 6-hydroxydopamine or Captopril. When these two drugs were used together, the attenuation effect was complete. While hypertonic saline significantly increased plasma Na+ concentration, normal saline only gave rise to a decrease. Intracerebroventricular injection of hypertonic NaCl solution also facilitated the recovery of MAP significantly. These results suggest that after hemorrhage increased plasma Na+ concentration following i.v. of a small amount of hypertonic saline may act on the central nervous system and activate sympathetic nervous system and renin angiotensin system to facilitate a rapid recovery of MAP.