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I thought that I write an explanation of what flow cytometry is

Submitted by ziweiwang on Thu, 09/19/2019 - 23:48

I actually almost laughed out loud, during class when I saw the article title How I learned to love flow cytometry. Because it was so accurate of an title. Over the summer, I actually got some experience working with the machine, and it takes quite a long time to get used to, and it was one of the things that I never quite got used to. I got used to handling mice before even being able to explain how flow cytometry work properly. Being fair, it hurt a lot less to handle flow cytometry. The machine had a lot of problems, but biting the people handling them was not one of them. to be honest, I still can't explain it very well, and if I don't write it down somewhere I will probably not be able to remember any of it. 

Basically, flow cytometry is when cells are labeled with specific antibodies and tags then the cells are passed through the machine to detect certain proteins such as antigens and other proteins. when the cell is passed through the tube the computer shines the laser at it and record the size of the cell, the weight of the cell, and what label it has. the scientist using the machine can change the graphs so that they can make a bunch of graphs that suit their needs. one thing that can be done is to show whether the cells have clumped or not. another is how much of one cell is expressing a certain protein. By manipulating the graph, the researcher can see that in certain cell population such as t regulatory cells, certain protein is missing in mice that are missing certain mutations. Because there are not as many cells that are needed for this, the technique is popular both in the lab and in a clinical setting. 

how I got the picture before I forget.

Submitted by ziweiwang on Thu, 09/19/2019 - 23:29

To take this picture, I walked to the closest vendor that was selling Spinacia oleracea leaf.  the leaf that I got specifically was baby spinach, not of the larger variety. I specifically chose a leaf that was not previously damaged and had a relative rounder leaf, and it was still fresh enough that it did not wilt when held up, even at the edges.  I then took a picture of the leaf, holding it by the stem, against a gray background and took a picture.  I held the stem so that most of the stem was covered up by my hand and the only the leaf was visible. When I was taking the picture, I held it up close enough that the leaf was relatively center and filled almost the entire picture rather than just around the corners. the picture that I took was slightly blurry, and as a result, the full-color difference between the differing part of the leaf was only slightly visible.  Then I took a bite that was large enough to cover half of the leaf, held it up again much in a similar position but with further distance so that the hand and the leaf fit within the bottom half of the picture, which was in portrait mode.  and took another picture with a similar background.  

While it does not matter where the plant leaf was obtained personally I obtained the leaf at one of the dining halls at University of Massachusetts Amherst. Specifically, the one that I have pointed out in the map. The gray background was the high chairs that they had at the dining halls.  However, as long as the leaf is baby spinach and the background is a similar color, there should not be any reason why the picture would be different. 

 

 

summary of methods from a study on LDL

Submitted by ziweiwang on Thu, 09/19/2019 - 22:55

In the study with the LDL, 25 patients with high blood LDL, was gathered. The 20 of patients had high blood cholesterol, but none of the patients were likely to have FH.  Five patients with heterozygous FH has gathered apart from the 20 patients. The participants with heterozygous were determined by their high LDL blood level in the blood which was much higher than the patients. The 20 participants were given two types of labeled LDL. The first type of LDL that was used is the patient's own LDL, which was extracted by their blood, labeled and inserted back into the body. The other type of LDL was obtained from first-year medical students who had normal blood cholesterol levels and fit the criteria for giving blood. The patients were then all admitted to the hospital for the study and were given a relatively high-fat diet.  The LDL turn over was studie by taking blood from taken from the donors and removed and the amount of the two labeled LDL was detected. 

The result of the study is that while in patients with Het FH, neither LDL was absorbed well. In some of the 20 patients who did not have FH, the patients had a much higher turnover rate of medical student's LDL compared to their own LDL. This indicates that the patient's own LDL is not structurally compatible with the LDL receptors in the cell, and indicate that the patients were unable to make normal LDL. since the absorption of the LDL in the blood causes the cells to decrease the production of LDL, it is not unreasonable to say that the unusual structure of the LDL protein is the cause of high cholesterol in these patients. If that was a true one of the ways that it can be treated is to inject LDL from someone else in to their blood. However, this treatment is not cost-effective, since the patients who have a misformed LDL inly have a slightly higher pressure than normal. 

study summary

Submitted by ziweiwang on Thu, 09/19/2019 - 21:27

 

    The question that is posed in the research is what effect does differing hemoglobin from patients with sickle cell anemia on lung epithelial tissue.

The data tells us that sickle cell hemoglobin causes the cells to oxidative stress. In addition, the epithelial cells fail to function as a barrier when the cells were exposed to HSE and Hbs. While the Hbs and HbE ferryl hemoglobin caused bioenergetic impairment in cells,  a similar result was observed in HbA from healthy people

The experiments concluded in the discussion that while all of the hemoglobin variants caused damage to the cells, the Hbs and HbE were less stable than HbA, and as a result, were more likely to lead to heme loss in the proteins. In addition, Hbs and HbE both allowed higher permeability of epithelial cells, but not in HbA. The conclusion of the data assumes that while free Hb in the blood by itself is damaging. However, if the Hb was of the variant where the Hb is less structurally sound, as in dysfunctional Hb, there was more damage to the function of other cells. 

 

The impact on SCD is that while it was thought that just the presence of free Hb in the blood is damaging, because of the protein instability of Hb in patients with sickle cell anemia, their Hb are more likely to be damaging to the lung epithelial cells compared to Hb protein from someone who is not ill. The fact that it is more damaging indicates that when researching the treatment of SCD symptoms, a model that uses a normal Hb would not be an accurate representation of the symptom of people with SCD. Knowing this would create a better model for a scientist to use to research treatments. 

 

mechanism of a study

Submitted by ziweiwang on Thu, 09/19/2019 - 21:26

The first experiment that they did, the experiment involving adding hemoglobin to lung epithelial cell culture answer the question by modeling what happens in the body If there were Hemoglobin S, Hemoglobin SE, and hemoglobin A, normal hemoglobin) was floating in the bloodstream. In the experiment, they measured the permeability by having the epithelial cells grow on a membrane rather than in a flask. Then they measured the permeability of the culture by adding media containing dextran on the top layer and measuring how much dextran there were in the bottom layer. At this stage, they also added hemoglobin to the top layer to see if the hemoglobin had any effect on the permeability of the cell layer. The cells were then washed and immunoblotting and microscopy were done on the cells to visualize how the hemoglobin had an effect on the cells. The researchers also measured the amount of oxidative stress that the cells had gone through by measuring the epithelial lipid hydroperoxide levels.  Mitochondrial Bioenergetic and glycolytic levels were also measured to assess the damage in the cells. The procedure of this experiment is simple in the sense that they had a model and exposed the model to the same environment as those that would be found in sickle cell disease patients, and assessing if there were any damage that the cells sustained. While this experiment does not exactly measure the dysfunction that is present in the hemoglobin (as for example, exactly how and why it is dysfunctional), it measures what the hemoglobin dysfunction causes in other cells (what does the dysfunction of the protein does to other cells?).

 

interesting thing about science

Submitted by ziweiwang on Tue, 09/17/2019 - 01:53

in the article and the data set that was studied in class so far, the data indicated that in patients with FH, they have a receptor lacking which allows them to take up LDL, which contains cholesterol into their bodies. This is partically because they have a mutation that prevents them from having a functional receptor. On the other hand of the spectrum are patients who do not produce LDL that can be absorbed into the body. Because these two mutations both end up having the same effects, namely neither one of them is able to get into the cell, the body reacts in similar ways, with patients that have FH and malfunctioning LDL both having a higher amount of cholesterol in the blood compared to a normal person. Because of the high cholesterol, these people are also more likely to get heart diseases and are at risk for cardiac arrest. However, the degree to which the person suffers differ depending on which mutation type that person has. If the person has a malfunctioning LDL, they are more likely to have heart disease and high cholesterol, but they are noticeably less severe compared to people who have an FH mutation. People who have this mutation, especially those that are homozygote for it is very likely to have cardiac arrests in their 40s if they are het and in their teenage years if they are mut for the gene. It is interesting to note that even though the mutation does have similar effects, the overall effect on the entire system is completely different. Trying to determine the cause of why such a thing happens is both a scientific and logical feat in which the research will need to be explained and the reason why such a result will mean that the evidence supports one side of the proposed reason over another one. Personally, I think that this is one of the most difficult things in doing research. the techniques are relatively easy once a person gets used to it, but trying to prove something to be true through logic is still difficult. For example, darwins theory of evolution is logical to the point that if all facts were removed from it it would all make sense. All it needs to be done now is to just prove the basis of the logic to be correct, and the theory has to be correct.

what I did in a day

Submitted by ziweiwang on Fri, 09/13/2019 - 15:30

The category that I have the most activities on is hygiene. However, when I listed the amount of time that I spent on each activity, I also spent the least amount of time on hygiene. I think that this is due to the fact that while there are many varieties of things that I do throughout the day that is related to hygiene but none of them actually take very long.  For example, brushing teeth and washing face only takes 5 min even the longest activity in this category, taking a bath, 45 min, is still shorter than things like reading, which I do at stretches of hours at a time. It is also interesting, at least to me that this category is the most reflexive of all of the categories. almost everything comes in the sets of twos. I brush my teeth twice a day. I change twice, I put on make up, and I take it off. This shows that the category often bookends the day. This is different from things like work where I just do a certain thing at a certain time and never come back to it at a later time. The short time, the number of activity and the fact that it bookends the day indicates that this category of the day is something that is necessary to my daily life but is not necessarily something that I would think to myself that this is something that I'm going to do today.

 

 

 

hygiene

work

reading

food

 

 

 

comparing articles

Submitted by ziweiwang on Fri, 09/13/2019 - 01:30

Each section of the shorter article was structured in such a way that each section talked about a new idea on the topic. The different paragraphs also talked about different details that were disparate entities but come together into a single coherent idea. However, the structure of each individual section was not to necessarily have an introduction, main point, and conclusion, but to describe the idea of what the section is about in detail, using as much paragraph as necessary to communicate the information. The role of each section is to add to the previous section so as to help explore the questions that were introduced in the introduction and add to the conclusion that the author makes in the end. The role that first paragraph play is to add the important details that are presented in the title.

the ocular development in humans.

Submitted by ziweiwang on Fri, 09/13/2019 - 01:14

One of the interesting things about the human eye is that it adjusts during the growth of a person. If a person is looking at something close constantly, the person is liable to become myopic. It is the same for the opposite direction. Because of this, currently, the condition is a certain indicator of economic status and the professions of the people who have the condition. People who works at a desk and were university-educated are more likely to be myopic compared to people who are farmers and does not focus on a screen all day. The reason for this flexibility is not originally due to differences in the roles that differing sexes play in society or to allow humans to fit into different niches of society, much in the same way how our sleep schedule differ depending which allow for different roles in our social circles. Another reason that was proposed is that the plasticity of the eye is used for the opposite, that since sight is one of the most important senses for humans it is of absolute importance that everyone has similar eyesight. The plasticity of the eye can help with that by modifying the eye to be more or less the same. 

Because of this plasticity of the eye,  some doctors have suggested that children should get glasses that have a degree of correction that is slightly lower than it needs so that the eye can grow and compensate for myopia naturally. However, it is agreed by doctors that some correction for myopia should be taken.

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