Adenylate Kinase 4—A Key Regulator of Proliferation and Metabolic Shift in Human Pulmonary Arterial Smooth Muscle Cells via Akt and HIF-1α Signaling Pathways

Increased proliferation of pulmonary arterial smooth muscle cells (PASMCs) in response to chronic hypoxia contributes to pulmonary vascular remodeling in pulmonary hypertension (PH). PH shares numerous similarities with cancer, including a metabolic shift towards glycolysis. In lung cancer, adenylate kinase 4 (AK4) promotes metabolic reprogramming and metastasis. Against this background, we show that AK4 regulates cell proliferation and energy metabolism of primary human PASMCs. We demonstrate that chronic hypoxia upregulates AK4 in PASMCs in a hypoxia-inducible factor-1α (HIF-1α)-dependent manner. RNA interference of AK4 decreases the viability and proliferation of PASMCs under both normoxia and chronic hypoxia. AK4 silencing in PASMCs augments mitochondrial respiration and reduces glycolytic metabolism. The observed effects are associated with reduced levels of phosphorylated protein kinase B (Akt) as well as HIF-1α, indicating the existence of an AK4-HIF-1α feedforward loop in hypoxic PASMCs. Finally, we show that AK4 levels are elevated in pulmonary vessels from patients with idiopathic pulmonary arterial hypertension (IPAH), and AK4 silencing decreases glycolytic metabolism of IPAH-PASMCs. We conclude that AK4 is a new metabolic regulator in PASMCs interacting with HIF-1α and Akt signaling pathways to drive the pro-proliferative and glycolytic phenotype of PH.     

A Targeted Releasable Affinity Probe (TRAP) for In Vivo Photocrosslinking

A protein TRAP : The in vivo photocrosslinking of TRAP after its intracellular targeting to a binding sequence on the bait protein stabilizes protein interactions. Because the crosslinker is releasable, simple mass spectrometry can be used to identify the protein binding sites after purification.

     

白鬼笔蘑菇菌丝体多糖：免疫调节和伤口愈合特性（英文）

白鬼笔蘑菇在亚洲和北欧是一种传统的民间医药。本文综述了我们人工培养白鬼笔菌丝体的研究成果,以及从白鬼笔菌丝体中分离出的多糖的生物活性数据。对白鬼笔新菌株菌丝体的培养形态特征和生理生化特性进行了研究。经过优化培养基的营养物构成和培养条件能够使菌体生物量提高1.3倍,多糖含量提高1.5～1.7倍。从该菌丝体中分离的多糖在体外和在体内(链脲佐菌素诱导的糖尿病大鼠)均具有免疫调节作用。与原始软膏相比,含有10%白鬼笔多糖的软膏,能促进实验大鼠的皮肤创面愈合,促进肉芽组织的上皮形成、收缩和生长。综上所述,白鬼笔菌丝体多糖有望成为开发功能性食品以及新型治疗和预防药物的原材料。     

Study of the Process of Destructive Hydrogenation of Powder Intermetallic Systems. Part 2. Rate of the First Destructive Hydrogenation of the Intermetallic TiNi

We have studied the rate of the first destructive hydrogenation of the as-poured bulk powder and compacts of TiNi. We have established that it is determined on the whole by the rate of processes that occur on the surface of the particles and are connected with formation of catalytic sites for dissociation of hydrogen, and by the rate of processes within the volume of the particles that is controlled by the rate of hydrogen diffusion and decomposition of TiNi. The first destructive hydrogenation of bulk TiNi powders is a lengthy process that can take tens of hours. Its rate increases as the temperature and hydrogen pressure increase. The effect of particle size is nonmonotonic because of the competing action of oxygen on the particle surface. Pressing TiNi powders made it possible to shorten the time required for the first destructive hydrogenation ten-fold (down to a few hours). This is connected with formation during pressing of fresh catalytic surfaces in closed cracks and on interparticle contacts. The rate of the first destructive hydrogenation of TiNi compacts increases as the temperature rises, and does not depend on particle size.__________Translated from Poroshkovaya Metallurgiya, Nos. 1–2(441), pp. 73–79, January–February, 2005.     

Novel condensation functional polymers having highly basic groups

The cardo polyimides and polyamides having highly nucleophilic quinuclidine groups have been synthesized with the usage of 3,3-bis(4-aminophenyl)quinuclidine as amine monomer. The latter has been obtained by the condensation of quinuclidone-3 with aniline. The characterization of such amine, including quaternization reaction, is performed. Polyimides have been derived from this monomer and various tetracarboxylic dianhydrides by one- and two-step polycyclization. Quinuclidine moieties enhance the one-step polyimide formulation leading to high molecular polymers including corresponding poly- 1,4,5,8-naphthoyleneimides even without any added catalyst. It is stated that polyamic acid formation is hindered by the side tertiary-amine-COOH salt formation. The latter reaction is eliminated by the preliminary quaternization of amine monomer. The high molecular polyamides have been prepared by low-temperature solution polycondensation of cited monomer and diacid chlorides. The obtained polymers are characterized by high thermal properties, solubility in organic solvents and represent the quite efficient catalysts for polyamic acid imidation in homo- and heterogeneous systems.     

Effect of rhodium on the properties of bifunctional MxOy/ZrO2 catalysts in the reduction of nitrogen oxides by hydrocarbons

The catalytic properties of transition metal oxides (Cr, Ce, and Co) supported on ZrO₂ synthesized by various methods, as well as the effect of rhodium on the performance of the M_xO_y/ZrO₂ oxide systems in NO reduction with hydrocarbons (methane, propane–butane mixture, and propene) were studied. Scanning electron microscopy, ammonia thermoprogrammed desorption (NH₃-TPD), XPS, and IR spectroscopy were used to study the physicochemical indices of rhodium-promoted M_xO_y/ZrO₂ oxide catalysts. The enhancement of the redox properties of the oxide catalysts upon the introduction of rhodium does not alter their bifunctional nature in SCR activity: these catalysts have both redox and strong acid Brønsted-sites.     

Milling of Carbide-Steel Powder Components and Their Mixtures in an Attrition Mill

Milling of wear-resistant steel and titanium carbide powders is studied with an attrition mill rotation rate of 980 rpm. The physical and technological properties of powders and particle size are determined. Particle shape and the change in material chemical composition during milling are studied. It is established that steel powder cannot be milled to particle sizes less than 3.6 μm whereas a mixture of steel and titanium carbide can be milled to a fine state (0.3 μm). Powders with a size of about 1 μm neither flow nor are formable. Use of benzene as a milling medium makes it possible to prevent steel powder oxidation, but the carbon content in titanium carbide decreases. During milling of the main part of the charge to a fine state rather large steel particles (up to 50 μm) remain.     

Orientation-controlled,low-temperature plasma growth and applications of h-BN nanosheets

Nano Research - Dimensionality and orientation of hexagonal boron nitride (h-BN) nanosheets are promising to create and control their unique properties for diverse applications. However,...