Association of a Novel Hsp70 Species with Brain Aging and Proteasome Dysfunction
Most neurological diseases are characterized by the presence of protein aggregates,\r suggesting that aberrations in protein homeostasis are associated with neuronal demise. In eukaryotic cells, protein homeostasis is maintained by the chaperone, ubiquitin proteasome (UPS) and autophagy systems. As age is a risk factor for several types of neurodegenerative diseases, the function of these various protein homeostatic systems could become compromised with age. To understand the events that occur during normal aging, we examined the expression of key markers associated with the aforementioned systems in mice aged 1, 3, and >18 months. We found that proteasome activity and the amount of proteasome-related structures remained unaffected with age. Interestingly though, an agerelated increase of a novel Hsp70 chaperone protein species (herein designated Hsp70*) was observed. The expression of Hsp70* is also increased markedly in cells treated with pharmacological agents that promote proteasome inhibition, suggesting a functional interaction between the chaperone system and the UPS. Taken together, our results suggest that there is some form of crosstalk between the chaperone system and the UPS involving the observed HSP70 species.
Delayed Apoptotic Cell Clearance Induce Autoantibody to huRNP P2
Deficiencies in clearance of apoptotic cells predispose to the development of autoimmune disease. This is evident in mice lacking the receptor tyrosine kinases Tyro3, Axl, and Mer that mediate uptake of apoptotic cells. Deficient mice exhibit an increased abundance of apoptotic cells in tissues and manifest diverse autoimmune conditions. To test these mice for the presence of autoantibodies to apoptotic cells, we generated spontaneous splenic B cell hybridomas and used microscopy to screen for clones reactive with apoptotic Jurkat cells. From hybridomas secreting IgG antibodies reactive with apoptotic cells, we selected one that recreated the major serum specificity for apoptotic cells. The antibody, LHC7.15, bound to an antigen that is differentially distributed between the nucleus and the cytoplasm in live and apoptotic cells. In late apoptotic cells, the antigen coalesces into aggregates that form blebs at the cell surface. Immunopurification of the antigen, followed by mass spectrometry, identifed a protein of 69kD whose partial sequence matched hnRNP P2. This multi-functional protein binds DNA, RNA, and several known RNP autoantigens. Our observations suggest that an RNP complex, formed and translocated to the cell surface in apoptosis, participates in the induction of linked sets of anti-RNP autoantibodies. Our results also implicate hnRNP P2 as a potential novel antigen involved in initiating and sustaining systemic autoimmune diseases.
由心血管超音波影像之動態分析研究主動脈硬化
我們的研究工作有兩項重要成果:首先,根據物理學的彈性體振動模型發現:主動脈硬化的定量分析訊息可由測量主動脈相對於心臟運動的延遲時間明確得知,而且可用目前臨床使用中的心臟超音波儀器直接進行此一測量。在對23 個樣品、每個樣品分析大約50至100 次心跳的初步研究中發現,此一延遲時間是確實存在的,而且延遲時間超過大約0.17秒時,樣品就可能具有動脈硬化的現象。其次,在比照過10 組樣品的數據後發現,上述之延遲時間確定可由體外的胸前超音波掃描(TTE)準確測得,而不需要採用侵入式的經食道超音波掃描(TEE),以免除受測者的不適,及避免副作用的風險,使得此一新方法更具有方便、普遍的優點。而且此一方法也可能由數據的分佈發覺心血管之其他病徵。未來仍需應用此一方法對較多樣品進行研究以進一步確定此診斷方法之可靠性。 Two important results were achieved in this research. Firstly, according to the physical model of elastic oscillation, we found that the qualitative analysis of aorta stiffness could be obtained by a measurement of the delay time of the aorta motion relative to the cardiac motion. This measurement could be carried out with the conventional echocardiography. A preliminary analysis based on 23 samples, with 50 to 100 heartbeats per sample, confirmed the existence of this delay time. Also, a delay time of greater than 0.17 sec might imply the symptom of aorta stiffness. Secondary, after a comparison of 10 samples, the aforementioned delay time could be measured with TaransThoracic Echo (TTE) instead of TransEsophadeal Echo (TEE), in which the later is invasive while the former is not. Therefore, the discomfort of the patient and the risk of invasive operation can be avoided, making this new method more convenient and more common to accomplish. This method could also clearly discern some abnormal cardiac performance. A large-scale study with this method should be conducted in the future.
Ancient Medicine- Modern Approach
The apricot kernel is believed to have a great medicinal value in many cultures. However, literature and research indicates that this belief still remains extremely controversial and conclusions regarding the medicinal value are ambiguous due to the presence of cyanide in the kernel. The focus of this research was to evaluate two objectives through the use of several integrated technologies and modified methods: (a) To successfully remove the cyanide from the apricot kernel using an adapted method; (b) To determine the effects of the cyanide free apricot kernel extracts on Helicobacter pylori and Streptococcus pyogenes bacteria. Procedures The apricot kernels were removed from the pits and then ground using a food processor. The kernels were then tested for cyanide using a cyanide test kit and Cyantesmo test tape. These tests indicated that cyanide was present. A novel approach was devised to remove the cyanide and when retested, the kernels tested negative for cyanide. This result was confirmed with Infrared Spectroscopy. The cyanide free kernels were then extracted using a Soxhlet Extractor with methanol for 24 hours. In addition to the methanol extraction, three other techniques were used to obtain kernel extracts: (a) Celite filtration, (b) Infusion Method A, (c) Infusion Method B. The Kirby Bauer method was modified for the microbiology aspect of this project. The Helicobacter pylori and Streptococcus pyogenes bacteria were plated using a 0.5 McFarland Standard. Paper filter discs containing 20µL of each extract were placed onto the inoculated plates in replicates of nine. After 48 hours of incubation, the zones of inhibition were read for each plate. Data The results were extremely encouraging and therefore to ensure the accuracy and preciseness of the data collected, four statistical analyses were completed. These include Confidence Intervals (CI), Standard Deviation (STDEV), T-Tests, and Chi Tests. The methanol extract was significantly different from the control in all trials. The Chi test also yielded a Chi Square value of 223, which was significantly greater than the critical value of 15.507, indicating that the results observed were not due to coincidence. Conclusion Literature evidence has indicated that the apricot kernel has been and is still used for medicinal purposes. Studies have shown that the presence of cyanide and the risks associated with this compound outweigh any benefits gained from the kernel. It has also been suggested that previous bacterial testing resulting in positive inhibition may have been due to the presence of cyanide. However, in this study, I was able to remove the cyanide through an innovative method to prove that the biological activity observed was highly unlikely to be due to cyanide. This indicates that there are other compound(s) in the apricot kernel that have specific antibacterial properties. The potential to improve the quality of life through the application of the apricot kernel appears to be supported, and further studies justified at this time.