Biomedical subjects

Ying Chen

Publications and source records attributed to Ying Chen.

292 records · Page 17Linked to original sources

PubMedDate not supplied

pH-induced self-assembly and capsules of sodium alginate.

In this investigation, we used a kind of polyelectrolyte, sodium alginate, as a model biomacromolecule to investigate the aggregation behaviors in aqueous solution after partial protonation of carboxylate groups in the alginate molecules. It is demonstrated that the alginate assemblies with core-shell structure can be generated by the partial protonation of carboxylate groups in sodium alginate chains using the protons released gradually from the reaction of K(2)S(2)O(8) with water at 70 degrees C in aqueous solution. The partial cross-linked alginate assemblies are pH sensitive and can change to hollow structure in the medium with relatively high pH value. This approach avoids use of block or grafted copolymers as the precursors or any other template to prepare assemblies and capsules, and provides a functional surface for subsequent chemical reaction at the surface (e.g., for binding biomolecules and for surface grafting). Such unique assemblies are also expected to be useful in biomedical fields.

Alginates↗

PubMedDate not supplied

Energetic depression caused by mitochondrial dysfunction.

Mitochondria, providing most of ATP needed for cell work, realizing numerous specific functions as biosyntheses or degradations, contributing to Ca2+ signalling also play a key role in the pathways to cell death. Impairment of mitochondrial functions caused by mutations of mt-genome and by acute processes are responsible for numerous diseases. The relations between changes on the level of molecules and the clinical state are rather complex, and the prediction of thresholds is difficult. Therefore investigations on different levels of an organismus (genome, metabolites, enzymes, mitochondrial function in vivo and in vitro) are necessary (multi level approach). Metabolic control theory is a valuable tool for understanding the different effects of mutations on the level of enzyme activities and mitochondrial function. Decreased concentrations of adenine nucleotides, leaky outer and inner mitochondrial membranes, decreased rates of mitochondrial linked pathways and decreased activities of respiratory chain enzymes contribute to depression of cellular energy metabolism characterized by decreased cytosolic phosphorylation potentials as one of the most important consequences of mitochondrial impairments. This review regards classical bioenergetic mechanisms of mitochondrial impairment which contribute to energetic depression.

Animals↗

PubMedDate not supplied

Energetic depression caused by mitochondrial dysfunction.

Mitochondria not only provide most of the ATP needed for cell work and numerous specific anabolic and catabolic functions, they also contribute to Ca++ signalling and play a key role in the pathway to cell death. Impairment of mitochondrial functions caused by mutations of the mt-genome or by acute processes, is responsible for numerous diseases. Decreased concentrations of adenine nucleotides, leaky outer and inner mitochondrial membranes, and decreased activities of respiratory chain enzymes contribute to depression of cellular energy metabolism, one of the most important consequences of mitochondrial impairment as characterized by decreased cytosolic phosphorylation potentials.

Adenine Nucleotides↗

PubMedDate not supplied

Species-specific polymerase chain reaction amplification of camel (Camelus) DNA extracts.

A sensitive polymerase chain reaction (PCR) method based on amplification of a specific DNA fragment was established for the identification of camel (Camelus) materials. The species-specific primer pair L183/H372 was designed based on the nucleotide sequence of the mitochondrial cytochrome b gene, and its specificity was confirmed by amplification of 3 camel (domestic double-humped camel, wild double-humped camel, wild one-humped camel) samples and 11 non-Camelus animal (sheep, goat, pig, chicken, cattle, fish, dog, horse, donkey, deer, and rabbit) materials. An expected 208 base pair fragment was amplified from camel materials; no cross-reactive or additional fragments were generated from other animal materials. Taq I restriction endonuclease digestion of the unpurified PCR product can be used routinely to confirm the camel origin of the amplified sequence.

Animals↗