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An emerging body of evidence indicates that transient receptor potential TRP channels act as important mediators for a wide variety of physiological functions and are potential targets for drug discovery. Our previous study has identified transient receptor potential channel 3 (TRPC3) and TRPC6 as cation channels through which most of the damaging calcium enters, aggravates pathological changes in vivo and increases ischemia/reperfusion (I/R) injury in mice. This study aimed to verify the effects of TRPC3 inhibitor Pyr3 on myocardial I/R injury in mice. C57BL/6J wild-type male mice (8 to 12 weeks old) were anesthetized with 3.3% chloral hydrate. A murine I (30 min)/R (24 h) injury model was established by temporary occlusion of the left anterior descending (LAD) coronary artery. Pyr3 was administered at concentrations of 0, 2.5, 5, or 10 mg/kg via the right jugular vein 5 min before reperfusion. We observed that the selective TRPC3 inhibitor, 10 mg/kg Pyr3, significantly decreased the infarct size of left ventricle, and reduced the myocardial cell apoptosis rate and inflammatory response in mice. In a conclusion, TRPC3 can function as a candidate target for I/R injury prevention, and Pyr3 may directly bind to TRPC3 channel protein, inhibit TRPC3 channel activity, and improve TRPC3-related myocardial I/R injury. Pyr3 may be used for clarification of TRPC3 functions and for treatments of TRPC3-mediated diseases.

This work placed an emphasis that constructing segregated boron nitride (BN)/carbon nanotube (CNT) hybrid network brought an immense benefit to enhance the thermal conductivity (TC) of poly(vinylidene fluoride) (PVDF) composites. The segregated composites ((CNT + BN)@PVDF) showed a high TC of 1.8 W/mK at the total filler fraction of 25 vol %, outperforming PVDF composites with random structure (CNT/BN/PVDF) and segregated BN structure (BN@PVDF) by 169% and 50%, respectively. Infrared thermal images further demonstrated that (CNT + BN)@PVDF exhibited superior capability to dissipate heat compared to BN/PVDF. The segregated architecture increased the effective utilization of fillers and interfacial thermal resistance between neighboring BN platelets was reduced by the bridging effect of CNTs. Molding pressure and temperature governed the integration of segregated networks and thus the enhancement efficiency of TC. The design of hybrid segregated structure holds promise in a broad range of the preparation of...

Cardiac hypertrophy is characterized by maladaptive tissue remodeling that may lead to heart failure or sudden death. MicroRNAs (miRs) are negative regulators of angiotensin II and the angiotensin II receptor subtype 1 (AGTR1), which are two components involved in cardiac hypertrophy. In the present study, the interaction between angiotensin II receptor subtype 1 (AGTR1) signaling and miR-155 was investigated. Rat H9C2 (2–1) cardiomyocytes were transfected with miR-155 analogues or inhibitors, then stimulated with angiotensin II to induce cardiac hypertrophy. miR-155 expression was revealed to be altered following transfection with chemically-modified miR-155 analogues and inhibitors in rat cardiomyocytes. In cell cardiac hypertrophy models, the cell surface area, AGTR1, atrial natriuretic peptide and myosin heavy chain-β mRNA expression levels were revealed to be lower in cells stimulated with miR-155 analogue-transfected cells treated with angiotensin II compared with cells stimulated with angiotensin alone (P

The protective effects of male hormones on the cardiovascular system are still in dispute. There is now ample evidence that testosterone level is negatively correlated to the incidence and mortality of cardiovascular disease in men. Endothelial progenitor cells (EPCs) play a vital role in endothelial healing and vascular integrity, which are useful for promoting cardiovascular health. In this study, we investigated the effects of dihydrotestosterone (DHT), a non-aromatizable androgen, on human EPC function and the activation of the phosphatidylinositol-3-kinase (PI3-K)/Akt pathway in vitro. EPCs were incubated with a series of concentrations (1, 10, or 100 nmol/L in DMSO) of DHT for 24 h or with 10 nmol/L DHT for different time (6, 12, 24, 48 h). EPC adhesion and proliferation and the activation of Akt were assayed by cell counting, 5-ethynyl-2′-deoxyuridine incorporation assay, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, and Western blot analysis. Our data demonstrated that DHT significantly increased the proliferative activity and adhesive ability of EPCs in a dose- and time-dependent manner, maximum at 10 nmol/L, 24 h (p

Pigs have been regarded as the preferred source of organs for human xenotransplantation. The aim of the present study was to explore the biomechanical properties of the bile duct in pigs and humans to provide evidence for liver xenotransplantation.Fresh bile duct specimens obtained from 50 pigs aged 3 to 12 months and five deceased human donors. The diameters and wall thickness of the bile duct were measured using a computer imaging analysis system. The pressure-diameter of bile ducts was tested with biomechanical equipment. The corresponding parameters were calculated: incremental elastic moduli (E(inc)), pressure-strain elastic modulus (E(p)), volume elastic modulus (E(v)), and compliance.The E(inc), E(p), and E(v) of porcine bile duct gradually decreases with age. However, the E(inc), E(p), and E(v) gradually increased after pigs aged 10 months. The E(inc), E(p), and E(v) of pig bile ducts aged 3 to 6, and 11 to 12 months were higher than that of humans aged 20 to 40 years (P.01). The changes in compliance of the porcine bile duct with age oppose those in elastic modulus. There were no significant differences in the elastic modulus and compliance of the bile duct between pigs aged 7 to 10 months and adult humans (P.05).The biomechanical properties of the bile duct of pigs aged 7 to 10 months match that of adult humans. The correlation between age and biomechanical properties of bile ducts in pigs implied that a pig aged 7 to 10 months should be chosen for pig-to-human liver xenotransplantation.

OBJECTIVES This study investigated the relation between biomechanical properties of the proper hepatic artery and sex in pigs and humans to provide the theoretical basis for selecting suitable donor in pig-to-human liver xenotransplant. MATERIALS AND METHODS The proper hepatic arteries of 32 Chinese Hubei white pigs (8 males, 8 females, 8 castrated males, and 8 ovariectomized females) and 10 deceased donors (5 human men, 5 human women) were obtained. The pressure-diameter relations of the proper hepatic arteries were measured on biomechanical test equipment to calculate the incremental elastic modulus (Einc), pressure-strain elastic modulus (Ep), volume elastic modulus (Ev), and compliance. Each sample was sliced into 5-μm frozen sections and stained with hematoxylin-eosin. RESULTS There were significant differences in Einc (F=10.24; P = .001), Ep (F=3.75; P = .001), and Ev (F=3.41; P = .002) of the proper hepatic arteries of female, male, and gonadectomized pigs; females had the lowest elastic modulus and the gonadectomized group had the highest (P < .01). There was a significant difference in compliance of the porcine proper hepatic arteries between the sexes, highest in the female group and lowest in the gonadectomized group (P < .01). No difference in the elastic modulus and compliance of the proper hepatic artery between the male pig and the human man. There was no difference between the female pig and the human woman. CONCLUSIONS There were differences in the biomechanical properties of the proper hepatic arteries of the female, male, and gonadectomized pigs. The biomechanical properties of the human men/women proper hepatic artery match those of the porcine male/female hepatic artery. The correlation between sex and biomechanical properties of the proper hepatic artery in pigs could imply that a pig of the same sex should be chosen for pig-to-human liver xenotransplant.

To obtain the biomechanical and morphological remodelling of hepatic arteries in swine with portal hypertension. A number of 20 white pigs was used, of which 14 were subjected to liver cirrhosis and portal hypertension (PHT) induced by carbon tetrachloride and pentobarbital; the rest were used as the control group. The biomechanical remodelling of the hepatic arteries was measured, namely, the incremental elastic modulus (E inc), pressure–strain elastic modulus (E p), volume elastic modulus (E v), the incremental compliance (C), the opening angle and the stained microstructural components of the vessels. The percentages for the microstructural components and the histologic data significantly changed in the experimental group, three incremental elastic moduli (E inc, E p, and E v) of the experimental group were significantly larger than those of the control group (P

Background: This study aims to obtain the biomechanical properties of ascending aorta and pulmonary trunk between healthy humans and pigs of different months, so as to provide necessary biomechanical experimental basis for anastomosing blood vessel in pig-to-human heart xenotransplantation. Methods: Ascending aorta and pulmonary trunks of the six deceased donors (male 4, female 2) and 42 Chinese Hubei white pigs aged 1–7 months were performed biomechanical test. The blood vessel was given periodic permanent loading and unloading, and repeated force-deformation data were obtained. The elastic properties of the blood vessels were obtained by curve from experimental data. Results: The biomechanical material constant of ascending aorta and pulmonary trunk of pigs did not increase with the increase of age (F = 14.569, P = 0.126). The biomechanical material constant of humans was basically similar to that of pigs aged 1–7 months (F = 12.264, P = 0.225). The elastic modulus was the biggest in pigs aged 7 months in comparison with that in other ages (F = 27.425, P = 0.032). There was no significant difference of elastic modulus of corresponding blood vessel between humans and pigs of different months (F = 17.328, P = 0.215). Conclusions: Our present study suggests that there was no significant difference of elastic properties of ascending aorta and pulmonary trunks between humans and pigs. From biomechanical aspects, anastomosis of corresponding ascending aorta and pulmonary trunks in the process of pig-to-human heart xenotransplantation may be feasible.

Investigamos la viabilidad de la vena umbilical humana (VUH) como sustituto vascular de pequeno calibre. Se obtuvo VUH de 50 fetos a partir de abortos espontaneos o partos normales con el consiguiente permiso. La edad gestacional vario desde 24 a 42 semanas y las parturientas tenian 20-30 anos de edad. Cada muestra se corto en secciones transversales congeladas de 5 μm y se tineron con hematoxilina-eosina (HE), tincion de Weigert, azul de anilina y naranja amarillo G. Mediante un sistema de analisis informatizado de imagenes se determinaron los indices morfologicos geometricos y el componente microestructural. El grosor medio fue de 0,186, 0,203, 0,237, 0,264 y 0,268 mm a las 24-27, 28-32, 33-36, 37-40 y 41-42 semanas, respectivamente (F = 133,35, p

We explored the feasibility of human umbilical vein (HUV) as a small-caliber vessel substitute. HUVs of 50 fetuses were collected on spontaneous miscarriage or labor with the pregnant women's permission. Gestational age ranged 24-42 weeks, and parturients were 20-30 years old. Each sample was sliced into 5 mum frozen transverse sections and stained with hematoxylin-eosin (HE), Weigert, aniline blue, and orange yellow G. The geometric morphological indexes and microstructural component were measured by a computer image analysis system. The media thickness was 0.186, 0.203, 0.237, 0.264, and 0.268 mm at 24-27, 28-32, 33-36, 37-40, and 41-42 weeks, respectively (F = 133.35, p0.01); diameters were 1.861, 1.962, 2.303, 2.464, and 2.465 mm (F = 37.35, p0.01), respectively. The media thickness and diameter of HUVs increased with gestational age. The elastin content of media increased at 24-40 weeks, but the collagen content and collagen/elastin (C/E) ratio decreased. Elastin content in the proximal segment was higher than in the distal segment [10.16, 6.36 Aa%, (Aa% is the unit of relative content, ie, the ratio of absolute areas to the total tested area of smooth muscle, collagen and elastin in the vascular wall) F = 5.77-12.3, p0.05], with the collagen to elastin (C/E) ratio increasing from the proximal to the distal segment (F = 7.63-13.4, p0.05). Our results suggest that the microstructural component of HUVs (2.0-3.0 mm caliber) at 37-40 weeks of gestation was similar to that of the small-caliber arteries and had moderate amounts of collagen and elastin and good elasticity, i.e., a good C/E ratio; therefore, HUV may be a substitute for small-caliber arteries (e.g., brachial, ulnar, radial, right coronary, anterior tibial, and posterior tibial). HUV is one of several graft materials that may be used when autogenous saphenous vein is absent or inadequate.

Nous avons explore la praticabilite de la veine ombilicale humaine (VOH) comme substitut arteriel de petit-calibre. Les VOH de 50 fœtus ont ete rassemblees apres avortement spontane ou accouchement avec la permission de femmes enceintes. L'âge gestationnel allait de 24 a 42 semaines, et les parturientes avaient 20-30 ans. Chaque echantillon etait decoupe en coupes transversales 5 mm congelees et colorees l'hematoxyline-eosine (HE), au Weigert, au bleu d'aniline, et au jaune orange G. Les index morphologiques geometriques et les composants microstructuraux etaient mesures par un systeme d'analyse informatise. L'epaisseur de la media etait respectivement de 0,186, 0,203, 0,237, 0,264, et 0,268 millimetre a 24-27, 28-32, 33-36, 37-40, et 41-42 semaines (F = 133,35, p

The intersystem crossing channels of gaseous 4H-pyran-4-thione were investigated using the CASSCF//TD-B3LYP methods and group theory. Calculated results show that phosphorescence and nonradiative decay via intersystem crossing to the S 0 state are simultaneous processes occurring at the T 1 state. The spin–orbit coupling constant in the S 0 /T 1 intersection is large, 〈T 1 ∣ H SO ∣S 0 〉 = 156.0 cm −1 and the computed average phosphorescence radiative lifetime is 136.5 μs. A rapid depletion of the S 1 state via intersystem crossing to the T 1 state can be mediated by the T 2 state, if spin relaxation is fast within the triplet levels. Our calculated results are in close agreement with experimental observations.

The reaction pathway and energies for the gas-phase CO 2 –CO conversion by W + are discussed from density functional theory (DFT) UB3LYP calculation at the relativistic effective core potential (ECP) of Stuttgart basis sets with W + and 6-311+G(2d) with CO 2 . The reaction mechanism between W + and CO 2 is an insertion–elimination mechanism. The W + inserts with no energy barrier into a CO bond resulting in an OWCO + insertion product. The intrinsic reaction coordinate for the insertion process has been defined and the reaction mechanism has been investigated by analyzing various structures along this path. Crossing points (CPs) are localized, and possible spin inversion processes are discussed by means of the intrinsic reaction coordinate (IRC) approach.

N 2 O 3 2 - photodissociation was investigated using the CASSCF energy gradient techniques. After the N 2 O 3 2 - dianion is populated in the S 1 state, the system can undergo different routes. One route involves radiationless decay via an intersystem crossing T 1 /S 1 to the T 1 minimum intermediate. Then through the transition state TS (T 1 ) and the T 1 /S 0 to the ground state surface. The other route involves the S 1 /S 0 conical intersection. These results show that the main product NO − of the efficient photodissociation is singlet-state rather than triplet ( 3 Σ − ) state. Our calculated results are in close agreement with experimental observations.

The reactivity of X(3P) (X=Ge, Sn, Pb) with N2O(X1Σ) on both singlet and triplet potential energy surfaces have been investigated at the B3LYP level of theory. To accurately evaluate the activation barrier and reaction energy, the coupled cluster single point calculations using the B3LYP structures is performed. The calculated results are in good agreement with experimental observations. The X ( P 3 ) + N 2 O ( X 1 Σ ) → XO ( X 1 Σ ) + N 2 ( X 1 Σ g + ) (X=Ge, Sn, and Pb) reactions that Arthur Fontijn has been observed are spin-forbidden for formation of ground state products in the experiments. The present paper is discussed with the aid of the direct abstraction (DA) mechanism (also called the surface crossing model), a correlation argument based on separated fragments X+O+N2 can explain the inefficiency of the X ( P 3 ) + N 2 O ( X 1 Σ ) → XO ( X 1 Σ ) + N 2 ( X 1 Σ g + ) (X=Ge, Sn, and Pb) reactions at 298 K by the need to switch electron configurations along low-energy adiabatic paths from ground-state reactants to energetically accessible XO ( X 1 Σ ) + N 2 ( X 1 Σ g + ) product states.

Aims Investigation of the response of mesenchymal stem cells (MSCs) to vascular mechanical forces is very important in the field of cardiovascular intervention. Ser/Thr-protein kinase Pim-1 is a novel transducer of cell survival and the cell cycle that promotes signals in the hematopoietic cell system. Current studies aim to foster an understanding of Pim-1 expression and regulation in MSCs in response to different durations and strengths of laminar shear stress (SS) and to investigate the role of Pim-1 in SS-induced cell proliferation. Main methods A parallel-plate flow chamber was used to control the strength and duration of SS. Proliferation was measured with the BrdU cell proliferation assay. The expressions of Pim-1 mRNA and protein were evaluated by reverse transcription-polymerase chain reaction and western blotting, respectively. RNA interference was used to knock down the Pim-1 gene. Key findings The results showed that SS up-regulation of Pim-1 mRNA and protein was time-dependent. Pim-1 induction was SS strength-dependent, and the expression level reached a maximum at 30 dynes/cm2. Inhibitors of p38MAPK and ERK attenuated the SS-induced expression of Pim-1. In addition, SS significantly increased BrdU-uptake, which was effectively blocked by the silencing of Pim-1. Significance These results demonstrated that Pim-1 is expressed in MSCs and plays an important role in the SS-induced proliferation of MSCs.

Endothelial cell migration and survival might be called “major angiogenic responses”. Tumor conditioned medium (CM) has been widely used to stimulate endothelial cells to form capillary-like structures in angiogenesis models in vitro. However, the molecular events triggered by tumor CM are not fully understood. Here, we examined the effects of the CM from human lung carcinoma cell lines A549 and SPC-A-1 on cultures of primary human umbilical veins endothelial cells (HUVECs). After treatment of HUVECs with the CM, cell migration was assessed by wound-healing assay, cell viability was evaluated by XTT assay, and apoptosis and cell death of HUVECs was analyzed by flow cytometry. Phosphorylation of Akt was assessed by Western blotting. To dissect the direct role of Akt, small interfering RNA (siRNA) against Akt1 was used. Both A549 and SPC-A-1 CM significantly stimulated cell migration. However, only A549 CM promoted cell viability and inhibited low serum-induced apoptosis and cell death of HUVECs, but SPC-A-1-CM showed no effects on survival of HUVECs. Meanwhile, A549 CM was found to be able to induce much more phosphorylation of Akt compared to SPC-A-1 CM treated group. The inhibitor of PI3K (wortmaninn) or Akt1 siRNA blocked A549 CM-induced migration and survival of HUVECs. These results indicated that the angiogenic effects of A549 CM are largely mediated through activation of the PI3K-Akt in endothelial cells, and that the Akt1 is crucial in this process, which may provide a therapeutic target for decreasing tumor angiogenesis.

Phenotype transformation of vascular smooth muscle cells (VSMCs) is known to be modulated by mechanical strain. The present study was designed to investigate how different frequencies of mechanical strain affected VSMC phenotype. VSMCs were subjected to the strains of 10% elongation at 0, 0.5, 1 and 2 Hz for 24 h using a Flexercell strain unit. VSMC phenotype was assessed by cell morphology, measurement of two-dimensional cell area, Western blotting for protein and RT-PCR for mRNA expression of differentiation markers. Possible protein kinases involved were evaluated by Western blotting with their specific antibodies. The strains at certain frequencies could induce a contractile morphology in VSMC with almost perpendicular alignment to the strain direction. The strains also regulated protein and mRNA expression of several differentiation markers, as well as the activation of extracellular signal-regulated kinases (ERKs), p38 MAP kinase and protein kinase B (Akt) in a frequency-dependent manner. Furthermore, the inhibition of the p38 pathway could block the frequency-induced phenotype modulation of VSMCs, but not inhibition of ERK or Akt pathways. These results indicate that the frequency of cyclic strain can result in the differentiated phenotype of VSMCs, and it is mediated at least partly by the activation of the p38 pathway.

To investigate the effect of human angiotensin II (AngII) type 1 receptor (AT(1)R) antisense cDNA (ahAT(1)) on migration, proliferation, and apoptosis of cultured human pulmonary artery smooth muscle cells (PASMC).Two recombinant adenoviral vectors, AdCMVahAT(1) containing full length antisense cDNA targeting to human AT(1)R mRNA, and AdCMVLacZ containing LacZ, were constructed by orientation clone technology and homologous recombination. The PASMC was divided into 3 groups (DMEM, AdCMVLacZ, AdCMVahAT(1)) and different interventions were given to different groups. AT(1)R expression was detected by RT-PCR and immunohistochemistry method; migration of PASMC was measured by Boyden's Chamer method. Other PASMC was divided into 4 groups (DMEM, AngII, AdCMVLacZ + AngII and AdCMVahAT(1) + AngII), and only the last 2 groups were respectively transfected with AdCMVLacZ and AdCMVahAT(1) before administration of AngII. From 6 h to 96 h after stimulation by AngII (10(-7) mol/L), proliferation index (PI) and apoptosis of PASMC were determined by flow cytometry.At the 48 h the level of AT(1)R mRNA was significantly less in PASMC transfected AdCMVahAT(1) than that in group DMEM and in group AdCMVLacZ. The protein level showed a same difference (P0.01). At 24 h the migration distance of PASMC also was significantly less in group AdCMVahAT(1) than that in group DMEM and Group AdCMVLacZ (P0.01). Stimulated by AngII for 48 h, in group AngII the PI of PASMC markedly increased (P0.01 vs group DMEM). But in Group AdCMVahAT(1) + AngII PI of PASMC clearly decreased (P0.01 vs group AngII and group DMEM respectively). There was no statistic difference of PI between group AdCMVLacZ + AngII and group AngII. Moreover, apoptosis peak emerged only in group AdCMVahAT(1) + AngII. The rate of apoptosis in those PASMC used AdCMVahAT(1) and AngII was 24.70 +/- 4.04 (P0.01 vs the other 3 groups respectively).These results indicate that AngII stimulates proliferation via AT(1) receptors in human PASMC, and antisense cDNA targeting to human AT(1)R transfection mediated by adenoviral vector has powerful inhibitory effects on AngII-induced migration and proliferation of human PASMC by attenuating AT(1)R mRNA and protein expression. Also, it can promote apoptosis of human PASMC. That demonstrate that AT(1)R antisense cDNA is a potent inhibitors of the actions of AngII on PASMC. Antisense inhibition targeting to AT(1)R has therapeutic potential for the treatment of pulmonary vascular diseases.

Vascular endothelial cells (ECs) are constantly exposed to blood flow-induced shear stress; these forces strongly influence the behaviors of neighboring vascular smooth muscle cells (VSMCs). VSMC migration is a key event in vascular wall remodeling. In this study, the authors assessed the difference between VSMC migration in VSMC/EC coculture under static and shear stress conditions. Utilizing a parallel-plate coculture flow chamber system and Transwell migration assays, they demonstrated that human ECs cocultured with VSMCs under static conditions induced VSMC migration, whereas laminar shear stress (1.5 Pa, 15 dynes/cm2) applied to the EC side for 12 h significantly inhibited this process. The changes in VSMC migration is mainly dependent on the close interactions between ECs and VSMCs. Western blotting showed that there was a consistent correlation between the level of Akt phosphorylation and the efficacy of shear stress-mediated EC regulation of VSMC migration. Wortmannin and Akti significantly inhibited the EC-induced effect on VSMC Akt phosphorylation and migration. These results indicate that shear stress protects against endothelial regulation of VSMC migration, which may be an atheroprotective function on the vessel wall.