Detection of apoptosis and matrical degeneration within the intervertebral discs of rats due to passive cigarette smoking.

Although low-back pain is considered to be associated with cigarette smoking, the influence of cigarette smoking on the intervertebral discs (IVD) has not been confirmed. We established a rat model of passive cigarette smoking-induced IVD degeneration, and investigated the cytohistological changes in the IVD and the accompanying changes in gene expression. IVD from rats exposed to 8 weeks of passive cigarette smoking were stained with Elastica van Gieson, and exhibited marked destruction of the supportive structure of the reticular matrix in the nucleus pulposus (NP). Positive signals on safranin O, alcian blue, type II collagen and aggrecan staining were decreased in the destroyed structure. Safranin O and type II collagen signals were also decreased in the cartilage end-plate (CEP) after 4- and 8-weeks of cigarette smoking. In the CEP, the potential for apoptosis was increased significantly, as demonstrated by staining for single-strand DNA. However, there were no signs of apoptosis in the NP or annulus fibrosus cells. Based on these findings, we hypothesized that passive cigarette smoking-induced stress stimuli first affect the CEP through blood flow due to the histological proximity, thereby stimulating chondrocyte apoptosis and reduction of the extracellular matrix (ECM). This leads to reduction of the ECM in the NP, destroying the NP matrix, which can then progress to IVD degeneration

Synthesis and Characterization of Photo-Responsive Carbosilane Dendrimers

Preparation of photo-responsive carbosilane dendrimers bearing 4-phenylazo-benzonitrile units on their molecular surface has been accomplished, and their both photo and thermal behaviors have also been characterized. These functional dendrimers suggest that the apparent molecular sizes of the cis-isomers are smaller than those of the corresponding trans-isomers, since the molecular diameter of these dendrimers would be shorter on the basis of trans→cis photo-isomerization of azobenzene

Isolation and amino acid sequence of a mating pheromone produced by mating type α cells of Saccharomyces kluyveri

AbstractA peptide, termed αsk2 pheromone, was isolated from culture filtrates of mating type α cells of Saccharomyces kluyveri as a mating pheromone, having both shmoo inducing (in a cells of S. kluyveri and S. cerevisiae) and agglutinability inducing (in a cells of S. cerevisiae) actions. The amino acid sequence of αsk2 pheromone was determined as H—Trp—His—Trp—Leu—Ser—Phe—Ser—Lys—Gly—Glu—Pro—Met—Tyr-OH by mass spectrometry, sequence analysis and enzymatic digestions