Uterus transplants, as they are technically known as, have been given the "go-ahead" with conducting research within the UK. In short what this means is, to start, 10 women who "don't have a functioning uterus', the way in which this will happen is the womb will be transplanted and left to heal for one year, after a year the recipients will use IVF to fertilise an egg in a lab and then implant the egg into the new uterus. This advance for womb transplants in the UK comes after a Swedish study in 2013 saw great success with 9 women having a transplant, 7 of which were healthy after a year, 4 of which went on to become pregnant. One main issue that has arisen from this advancement is where do we get the uterus' from. The Swedish researchers used the recipients mothers, this can maybe be a cause of the success they had, the organs have a reduced likelihood of being rejected. However the stigma specifically for the UK research is that they plan 'to use uteruses from women who are brain dead but whose hearts are still beating'. Personally I find this insensitive and I believe that the Swedish method would be much more appealing to everyone. The fact they are brain dead means that they are just vessels (different to being in a coma) and I understand the uterus has to be in a living body before hand but it feels like it is taking something from someone who cant say. Overall I agree with the fact that uterus transplant are a great thing and more research should be done to make it more common place
Measuring the population growth over time using turbidity
You can see from this table our absorbency results, due to being averaged across three recordings are large decimals. To simply this we can plot the results on a graph. This also allows to see trends and view anomalies.
These as a graph over time show a clear trend. The graph starts of with a low gradient for the first 18 hours and then the gradient increases dramatically and the absorbance initially peaks it then for the next 14 hours does not reach near the same value. After the second distinct peak the graph begins to fall until we stopped the readings which was after 74 hours.
Analysis of results
Before interpreting our results it is important to remember that the absorbance of light directly correlates to population of cells. Our results have a clear trend to them which I think mirrors that of the intended shape of number of cells over time. Because cell growth is exponential the growth is initially very slow causing what is known as a “lag phase” this can be seen up until 18 hours into the experiment. This is because the gradient is quite low relative to the rest of the graph. The sharp increase of the gradient after 18 hours up until 30 hours in known as the “log phase” in which most of the growth of the population occurs very quickly. Up until this point our results have mirrored the intended graph however our results fall and then rise. I believe our results here are incorrect as if we were to remove our results at 42 hours, 50 hours and 54 hours our graph would have a flat or very low gradient. This is indicative of the stationary phase in which the population has reached carrying capacity (K). This means that the population has reached the point where, for whatever reason (e.g. nutrients or space) the medium cannot support any more yeast cells. At the end of the stationary phase, or 66 hours, the population begins to fall. This is known as the death phase. This is most likely due to the nutrients, which was in the broth being exhausted by the large number of cells, or when the cells respire and reproduce they leave behind toxic material which over time accumulates and can eventually kill the population.
I believe our experiment was quite successful, overall I felt our results were very close to what was intended meaning that we did our experiment aseptically and followed the instructions well. I feel our only problem was that our stationary phase didn’t quite match to what it should have been. However as it was not a single result that off but three which had a general correlation between each other I feel that the issue was most likely the reference solution which we calibrated the colorimeter with. If it were not made with precise measurements with exact measurements it would affect readings taken uniformly. IF the reference solution had slightly more broth in that would lower the readings we would have taken. Although there is no way to prove this theory is correct, I believe it provides a logical answer to why our results went down when they should have not.
Cholera can be contracted from water due to the vibrio bacteria contaminating the original source. This water can then get into plants or animals who feed off of, or live in, the water. The main symptoms of cholera are watery bowels and vomiting which lead to dehydration. Other symptoms are heart rate, low blood pressure and cramps. If a patient presented with these symptoms I would take a tissue sample from them and I would culture it to see if actually cholera is the infection.
How to culture vibrio cholera
First of all we need to know exactly what vibrio cholera is, vibrio cholera is the bacteria that cause the disease cholera. It is a gram negative, comma shaped bacterium. It is also a facultative anaerobic organism, this means that the bacterium can aerobically or anaerobically respire with a preference for oxygen. They also have a flagellum at one side of the bacteria
Because these bacterium are vibrio this allows them to be cultured with TCBS. TCBS is a cocktail of many chemicals which each play a role in isolating vibrio bacteria. The thiosulfate-citrate, for example, inhibit the growth of Enterobacteriacae. All these chemicals work together to inhibit the growth of everything except vibrio bacteria. There are multiple vibrio bacteria so therefore if you tried culturing you may see multiple bacterium so therefore may be inconclusive. To culture vibrio cholera specificically you have to introduce an alkaline pH (of more than 8). This inhibits the growth of other vibrio bacteria and enhances cholera growth. When cholera is cultured the result should be “large yellow colonies” like on the picture below.
TCBS (Thiosulfate-citrate-bile salts sucrose agar) – “A type of selective agar that is used to isolate vibrio bacterium”
Vibrio – “A waterborne bacterium of a group that includes some pathogenic kinds that cause cholera, gastroenteritis, and septicaemia.
Antibiotic resistance: world on cusp of ‘post-antibiotic era
There exists a drug of last resort, a drug that when bacteria is resistant to everything else will kill bacteria. In China resistance to Colistin (the drug) has been shown in bacteria. Scientists have forecasted that this resistance will be spread around the world and there will be many more untreatable infections. Known as ‘The antibiotic apocalypse’ this phenomenon is when bacteria is completely resistant to known antibiotics. The affect will be wide scale, common infections may kill the old and young and recovering from surgery would be riskier than ever. It is also said that the transfer rate of this resistance is very high meaning the resistance will spread extremely quickly. This is a very scary prospect and somewhat relates to what we are studying in class at the moment, we are studying bacteria and bacteria replication. This is how the Colisitin resistance is being spread between bacterium
Aseptic - free from contamination caused by harmful bacteria, viruses or other microorganisms
However why is it so important to keep an experiment aseptic? Especially in an experiment like ours, where we were trying to see the growth of particular bacteria which we had intentionally scraped onto our agar. If any other bacteria were to get on the agar plate they would compete for the same nutrients and space as the intended bacteria. This would mean our results would be inaccurate and unreliable. Generally if we are trying to study and measure the growth of a specific bacteria we would not want to introduce new bacteria which would compete with the intended bacteria.
How to make an experiment aseptic
Synthetic biology is all about creating artificial DNA that is created in a laboratory and not found (but inspired) by nature. Synthetic in this case relates to the fact that the materials used in the creation of this DNA is artificial / synthetic. What is so shocking is the statistic that $25 worth of sugar is enough to model the human genome. This, to me, seems like a minute number compared with the millions of dollars of research poured into synthetic biology. The fact that so little money can give the potential to model so much means the possibilities of synthetic biology are not being held back by exorbitant costs. Along with this a base pair is just 40 cents. University students have been able to create in bacteria e.coli many different "machines". They can make this machines change colour after a stimuli has been detected. This could mean a temperature or a concentration. These are students with "shoe string budgets" (as said by the video) meaning that this is very much a reality.
They have been able to bring together different portions of genetic material and combine them in one bacterial plasmid to create a drug for maleria. The benefit of this is that the bacteria can reproduce and cultivate themselves meaning they can be cheap and readily available.
This relates to our course as synthetic biology is all about changing the DNA, this in turn, means that the synthethic DNA will be transcribed into mRNA which is then translated into proteins. These proteins are what gives the organism the properties that are so unique. The proteins are made by these synthetic DNA so the new DNA could be made into anything
Maybe not the cure for cancer but definitely a step in the right direction.
What scientist; Steve Benner has been able to do is add artificial base pairs, referred to as Z and P, which actively seek out cancer cells. This was achieved by finding the most cancer binding DNA. "This was repeated until they had strands of DNA that were no in the original population" - the DNA had evolved. This means that only Currently the scientists have yet to expand on this medical breakthrough. However the "foundations" for treating cancer have been built. Hinted by Floyd Romesberg in an interview, he suggested that now it is possible to selectively pick out and bind to cancer cells. It may be possible to selectively kill these cells. Before this could never be possible as there would always be a certain amount of crossfire with healthy cells being killed or damaged whilst trying to eradicate cancer cells. Now, chemically, scientists can avoid this issue and they can also make sure to kill all cancer cells. We are currently learning about DNA and its structure. Along with this is the nitrogenous bases, referred to as "the genetic alphabet" by the article, such as A, T, C and G (U being instead of T in RNA). The genetic alphabet doesn't need to end with a Z and a P, the possibilities now the method is there are endless.
For years scientists have been trying to utilise liposomes ("tiny bubbles of fat which carry material round the body") in order to administer toxic drugs to the tumour. However a few questions arose; how would the liposomes know where the tumours are, and how would they release the drugs when they get there? Liposomes have the property of, when being above 42C , beings soluble allowing their material, which is held securely under 42C , to be released. The human body should never get above 42C so the altered liposomes are harmless until heat is applied. By putting a heat probe into tumour the toxins will be released and can target the tumour therefore stunting growth / killing the tumour.