長期處理兒茶素對無機砷與氯化鎘之遺傳毒性
重金屬對人體傷害的無遠弗屆-人人皆知，根據流行病學的研究指出，長期處\r 在重金屬含量過高之地區，易造成生理病變。比方說，長期生活在砷含量高的環境\r 中，易導致肝臟、周邊血管及神經系的損害，各種癌症的發生機率也大為提高；長\r 期處在含量過高的鎘環境中，易引起不正常的鈣代謝﹐產生骨質疏鬆症、軟骨症、\r 糖尿、胺基尿酸、尿蛋白、貧血、和肝功能異常的症狀；而目前坊間所看到各類茶\r 品中含有的兒茶素則被發現具有抗氧化、抗突變及清除自由基等功能。故本實驗以\r 人類胃癌細胞(SC-M1)為材料，以微核(micronuclei)偵測技術觀察細胞長期處理兒茶\r 素((-)-epigallocatechin-3-gallate, EGCG)後，對於亞砷酸鈉(sodium arsenite, NaAsO?)\r 及氯化鎘(cadmium chloride, CdCl?)所造成的細胞遺傳毒性有何影響。另一方面則利\r 用SRB 分析法測量細胞存活率，探討長期處理兒茶素後，亞砷酸鈉及氯化鎘對於細\r 胞的毒殺情況是否改變。實驗結果顯示細胞長期處理兒茶素不會造成微核的增加，\r 但是卻會增加細胞的存活率；單獨處理亞砷酸鈉和氯化鎘則都會使細胞中微核明顯\r 的增加，且會降低細胞的存活率；而長期處理兒茶素的細胞對亞砷酸鈉所誘發的微\r 核有抑制作用且會增加細胞對於亞砷酸鈉的耐受度，長期處理兒茶素無法抑制氯化\r 鎘所誘發的微核與細胞毒性。\r \r \r It is well documented that exposure to heavy metals could cause seriously adverse\r effects to humans. Epidemiological evidence has shown that illness is frequently\r observed in residents living long-term in heavy metal contaminated area. For example,\r long-term exposure of arsenic was associated with increased incidences of liver diseases,\r peripheral vascular and neurological diseases, as well as cancers. And long-term exposed\r to cadmium may lead to abnormal metabolism of calcium, osteoporosis, osteomalacia,\r glucouria, aminoaciduria, proteinuria, anemia and abnormal liver function. Recently,\r numerous reports have shown that (-)-epigallocatechin-3-gallate (EGCG), the major\r polyphenol from green tea, have ability to anti-oxidative stress and anti-mutagenesis. In\r this report, we investigated the effects of EGCG long-term exposure in sodium arsenite\r and cadmium chloride induces chromosomal damages and cytotoxicity in a gastric cancer\r cell line, SC-M1. Our present results demonstrated cells long-term exposure to EGCG did\r not induce micronuclei (MN) formation but induce the growth rate. Sodium arsenite or\r cadmium chloride alone significantly induced MN formation and cytotoxicity in cells\r without long-term EGCG exposure. However, long-term treatment of SC-M1 cells with\r EGCG significantly reduced MN formation and protects the cells from cytotoxicity\r induced by arsenite. Long-term exposure of EGCG had no effect on MN induction and\r cell survival in cadmium-treated SC-M1 cells.
Investigation on traditional medicine from plants in Namibia
My project is about investigation on traditional medicines in\r Namibia. This is all about plants and different herbs that different\r people in Namibia use for medicinal purposes. The objective of this\r project is to inform the world of how valuable nature is and how we can\r try to conserve nature’s treasure so that valuable knowledge cannot pass\r away with olden experienced herbalists. Understandably the enquiry\r into indigenous medicinal herbs arose from the need to expand the\r possibilities of ones own medical practice. It was very important for me\r to satisfy our farmer’s thirst for knowledge, which is what I want to do\r with the rest of the world.\r In this project I have included most but not all of the plants that we\r use in Namibia for medicinal purposes. Seeing that some of these plants\r do not grow in certain parts of the country, I have also tried to clone it in\r other parts of the country. I have also made a powder from one of the\r plant’s leaves and tested it on several people within the country.\r To conclude my findings and experiments I would like to say, let us\r try to take these precious knowledge left for us from our ancestors and\r maybe one day in the future we might need it in some ways.
Blood Brain Barrier Breached!
The purpose of this project is to determine if it is possible to use Ascorbic Acid Sodium- Dependent Vitamin C Transporter Type II, SVCT2, as an effective and safe protein to attach to certain brain tumor treatments to bypass the Blood Brain Barrier (BBB). Stemming from this problem, a procedure was created to use in vitro engineering with the aid of a professor at the University of Calgary to combine SVCT2 and three specific tumor treatments; Imatinib Mesylate (STI-571), Temsirolimus (CCI-779), and Suberoylanilide Hydroxamic Acid (SAHA). Following this, a metabolic barrier had to be created to simulate the BBB. To do this, the use of three enzymes were mixed and held together using specific bonds. Finally, a special bio-tracer was placed within the barrier to detect any toxic effects that may be produced. Then two trials were made with each treatment on the barrier at 34°C, 37°C, and 39°C. Once this was done observations could be made. When the newly isolated SVCT2 attaches to the three cancer treatments, they would all be able to connect and form bonds with each other. Once the incubation period is over for the first trial at 34°C, 37°C and 39°C, several things would be observed within the data. When counting the number of cells that were able to get into the engineered metabolic barrier, it could be seen that there was a dramatic increase in the number of cells in the 37°C range. SVCT2 can be a powerful tool in combating cancer. Because of its specificity, it may prove to be more advantageous over the currently used drugs which may have unwanted toxic side effects on the CNS. In the near future, SVCT2 could have the potential to be adopted as a promising therapy against cancer and certain tumors. Furthermore, SVCT2 has the potential to be applied to many situations and can be modified to fit a number of situations that deal with getting past the Blood Brain Barrier. Initially, SVCT2 was only modified with three forms of treatment for Glioblastoma Multiforme, STI-571, CCI-779, and SAHA, however there are countless other treatments that have been developed, but that are not in use due to the BBB. This project was successful in determining an appropriate temperature of 37°C for the procedure to be used. The limitations of this experiment include the fact that this experiment was performed in vitro and so complexity among individuals cannot be analyzed. However, this is an early step for the future of SVCT2 as a treatment, and clinical trials to test SVCT2 in vivo may not be too far off.
Green tea causes preventing cancer
Now a days cancer is one of the most important factor of death in the world so we decided to introduce people one of the easiest way of it’s prevention. However, the relation between green tea and cancer is not completely identified but the research shows that drinking green tea reduce the state of cancer. First we found some information about the green tea compounds then we investigated the cancer factors in different countries and stidied the experiments among 900 women showed that drinking tea reduce the state of ovary cancer. Green tea contains A, B, C, D vitamins & Fe, folic acid &also minerals such as Ca, K, Zn. This useful soft drink is a strong Anti?oxidant so prevent any kinds of cancer & blood clot. Therefore it reduce the state of heart attack. (Up to 31%) So it is not only prevention factor but also it can open a new way to cure different cancers.
Keyboard for Blinds
The reason for making this project was with the intention to help the blind persons. A lot of people with vision problems don’t have the resources available to acquire equipment or programs that make it easier for them to use a computer to write, to communicate etc... Being aware of this problem we took the liberty of researching at a community center that helps the blind persons in Tijuana Baja California, Mexico. We found that they had a type writer (Perkins) with only 6 keys that symbolized Braille. They also had a normal keyboard that had the Braille code over each key, but it is complicated to learn because of its many keys. Due to our research our intention was to design a system that respect the Braille symbols of the Perkins type writer and translated them to the common alphabet. We believe that this project will help many people especially the blind, with writing books, letters, articles, etc. So they can be integrated to activities and jobs reserved, until now, for people with the sight sense. My project also has 8 keys, when the person press a key combination the PC emits the sound of the letter. And when a word is completed the PC reproduce the whole word on the speaker. When the entire paragraph is completed there is an option to reproduce it. It has also other functions as erase everything, back space, etc. All these with the 8 keys. To control the system I used the parallel port of a PC, with a control program made in Visual Basic. Currently there are systems for the blind but are very expensive, they have a cost of approximately $900.00 US dollars, which is a high price to pay for some people. My project has a cost of $70.00 US dollars thus making it easy for a person who has a computer to be able to buy this keyboard. This project is being use in the “Blind Persons Training Center” of Tijuana city. They helped us to develop it, giving some ideas to improve it.
新網路模式對抗無尺度流行病傳染A New Network Model to Fight Against Scale-Free Epidemi
流行病的傳染如同一個無尺度網路，但有一些特殊特性在發展一套新傳播模式時，是需要被詳加考慮的。我採用時間位移(t 與ti 分別以t?(ti?1)與ti?(ti?1)來取代)至無尺度網路模式中，再引入一個非連續強力函數H(t; ti?1, L+ti?1)來描述流行病傳播的特定時段與強度，並重新定義機率p 為無效傳染率。之後，我建立了新模式「無尺度流行病模式」－SFE-1與SFE-2。模擬六種病原的傳染途徑，結果證實SFE-1與SFE-2模式是正確與確切可用。案例研究結果，顯示傳染強度H可為固定值或為變數；p可以是一固定值、雙固定值或為新增病例的函數。更進一步解析美國AIDS病例在不同族群與行為上的差異，獲知亞裔/太平洋裔與印第安人/阿拉斯加人的H值低於其他族群，其原因可能是由於小的族群具有較高的接觸所致。異性性接觸的H值低於其他，顯示性交易是傳播HIV的主要途徑。SFE-1與SFE-2模式也可被用在流行病的預測上，因為SFE-2使用已知值而非估算值，所以SFE-2模擬結果較佳；但是SFE-1更可以明確提供一個流行病在失控或控制下的預測結果。無尺度流行病模式可以協助所需警戒的程度與政策決定的計畫結果。因此在幫助政府評估社會經濟成本與健康憂慮上是一個有用的工具。所以我提出一個確切可行的對抗無尺度流行病傳染新方法，並詳細說明運作流程。The course of epidemics resembles a scale-free network, but some specific elements should be considered in developing a new model. I introduced a time shifting (replacing t and ti by t?(ti?1) and ti?(ti?1)) and a discontinuous forcing function H(t; ti?1, L+ti?1) into the scale-free network model to fit the specific period and intensity of the infection, and redefined the probability p as an invalid infection rate. Then I proposed the new Scale-Free Epidemic Models, SFE-1 and SFE-2. The simulation results of six types of epidemic transmission showed that the SFE models were accurate and useful. In the case studies, the results showed that H were constant or variable, and p were a fixed constant, a dual constant, or a function of new addition cases in the epidemic periods. The further studies for comparisons of the difference races/ethnics and the difference transmission category of AIDS cases in USA were analyzed. The H value for Asian/Pacific and Indian/Alaska Native race were lower than others, it may be due to small clusters with constant high contact rates. The H value for heterosexual contact was lower than the others, indicating that whoredom was the main transmission for HIV. Both SFE models can be used to predict epidemics, SFE-2 is better than SFE-1 due to SFE-2 using given indices and not conjectured values, but SFE-1 can more clearly suggest results of epidemics when under control or not. SFE models can help the government to determine the level of caution needed and the projected results of policy decisions. They are useful tools in assisting to balance socio-economic and health concerns. I hereby propose a new method to fight against epidemics with detailed procedures of using the SFE models.
吸菸、喝酒與嚼檳榔之基因毒性研究
流行病學資料顯示，近年來口腔癌發生率明顯增加。本研究之目的是探討口腔黏膜細胞微核發生頻率及彗星分析法之基因傷害指標是否與菸、酒、檳榔暴露有關，以及是否可以看到菸、酒、檳榔之交互作用。 研究對象為桃園地區山地鄉之民眾，利用問卷收集個人之菸、酒、檳榔及干擾因子之暴露資料，再採集樣本之口腔黏膜細胞及血液樣本，進行基因傷害評估。 結果顯示，口腔黏膜之微核發生率與檳榔之暴露相關性最大，可以解釋12.6％；然而，彗星尾部動量和尾部長度則以香菸暴露解釋力最大；同時，檳榔與香菸的基因傷害交互作用似乎存在。因此我們認為，口腔黏膜細胞之微核發生頻率對於檳榔暴露者應是不錯的基因傷害指標，而香菸暴露則以彗星分析法之指標較為敏感。 ;Epidemiological studies showed that the incidence of oral cancer increased significantly in recent years. The purpose of this study is to evaluate the genotoxicity of cigarette smoke, alcohol and betel quid use as well as the. interaction effect between these three risk factors. The study subjects were selected from residents lived in a mountain area of Tao-Yuan county. We used questionnaire as a tool of exposure measurement. The exfoliated oral buccal cells and blood samples were collected for the assay of micronucleus frequency (MNF) and comet assay. We find that there are higher MNF in smokers, alcohol drinkers, and betel quid users compared with nonusers. However, a significant difference can not be found because of small sample size. The relationship between MNF and three risk factors was strongest in betel quid use, however, for smokers the parameters in comet assay were more sensitive than MNF. There is a tendency of additive effect between cigarette, alcohol and betel quid although without statistical significance. Advanced statistical analysis is suggested to find stronger evidence in the genotoxicity biomarker.