Biomedical subjects

Can Jin

Publications and source records attributed to Can Jin.

4 recordsLinked to original sources

PubMed2005

[The use of intermaxillary fixation screws in the management of jaw fractures].

48 patients with fractures of the jaw bones were included in this study. Intermaxillary fixation screws were used for tractions between the upper and lower jaw and to regain occlusion relationship, followed by internal rigid fixation. Two days after reduction of the fractures, intermaxillary tractions were carried out and the fixation screws remained for 2 weeks. All the wounds healed primarily with good occlusion. The wounds for screw placement healed well 3 to 5 days after removal of the screws. Excellent occlusion recovered in 45 patients, while in 3 patients, mild open bite developed which returned to normal after 2 weeks of intermaxillary tractions. It is concluded that intermaxillary fixation screws are time saving and efficient in the management of jaw fractures.

Bone Screws↗

PubMed2004

Bcl-2-mediated alterations in endoplasmic reticulum Ca2+ analyzed with an improved genetically encoded fluorescent sensor.

The endoplasmic reticulum (ER) serves as a cellular storehouse for Ca(2+), and Ca(2+) released from the ER plays a role in a host of critical signaling reactions, including exocytosis, contraction, metabolism, regulation of transcription, fertilization, and apoptosis. Given the central role played by the ER, our understanding of these signaling processes could be greatly enhanced by the ability to image [Ca(2+)](ER) directly in individual cells. We created a genetically encoded Ca(2+) indicator by redesigning the binding interface of calmodulin and a calmodulin-binding peptide. The sensor has improved reaction kinetics and a K(d) ideal for imaging Ca(2+) in the ER and is no longer perturbed by large excesses of native calmodulin. Importantly, it provides a significant improvement over all previous methods for monitoring [Ca(2+)](ER) and has been used to directly show that, in MCF-7 breast cancer cells, the antiapoptotic protein B cell lymphoma 2 (Bcl-2) (i) lowers [Ca(2+)](ER) by increasing Ca(2+) leakage under resting conditions and (ii) alters Ca(2+) oscillations induced by ATP, and that acute inhibition of Bcl-2 by the green tea compound epigallocatechin gallate results in an increase in [Ca(2+)](ER) due to inhibition of Bcl-2-mediated Ca(2+) leakage.

Adenosine Triphosphate↗

PubMed2003

Yeast dihydroxybutanone phosphate synthase, an enzyme of the riboflavin biosynthetic pathway, has a second unrelated function in expression of mitochondrial respiration.

aE280/U1 is a pet mutant of Saccharomyces cerevisiae partially deficient in cytochromes a, a3, and cytochrome b. The ability of this mutant to respire is restored by RIB3, a gene previously shown to code for 3,4-dihydroxy-2-butanone-4-phosphate synthase (DHBP synthase), an enzyme of the riboflavin biosynthetic pathway. The sequences of RIB3 from wild type and aE280/U1 indicated a single base change resulting in an A137T substitution. The alanine 137 is a conserved residue located in a cavity on the surface of the protein distant from the active site and from the subunit interaction domain involved in homodimer formation. The respiratory defect elicited by this mutation cannot be explained by a flavin insufficiency based on the following evidence: 1) growth of the aE280/U1 on respiratory substrates is not rescued by exogenous riboflavin; 2) the levels of flavin nucleotides are not significantly different in the mutant and wild type. We proposed that in addition to its known function in riboflavin synthesis, RIB3 also functions in expression of mitochondrial respiration. Restoration by riboflavin of growth of a rib3 deletion mutant on glucose but not glycerol/ethanol also supported this conclusion. An antibody against the N-terminal half of DHBP synthase was used to study its subcellular distribution. Most of the protein was localized in the cytosolic fraction, but a small fraction was detected in the mitochondrial intermembrane space.

Cell Compartmentation↗

PubMed2002

Yeast and apoptosis.

Even though yeast lack much of the molecular machinery that is responsible for apoptosis in metazoans, they can be a powerful tool in apoptosis research. The ectopic expression of several animal apoptosis proteins in yeast can help us to discover new genes -- and chemical compounds -- that modulate the cell-death pathways of higher eukaryotes.

Animals↗