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The vector used in this study is based on the herpes simplex virus genome (HSV). Wildtype HSV mainly infects sensory neurons. After infection, it resides in a latent state in the nervous systems of the host for a lifetime. The viral genome persists in the cell, without integrating into the host genome (Marconi et al., 2000). The article cited is devoid of ...


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The Stanford article that you read is correct, in the sense that telomeres do not need to be completely removed by cell division before deleterious effects occur and cells start undergoing senescence. This Nature article describes an experiment in which the minimum length of telomeres (beyond which chromosomal fusion occurs) was determined: The ...


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There is a large amount of variation in the distribution and number of chiasmata or crossing overs (COs). The total number of chiasmata per cell can vary within the same organism. Where chiasmata occur along the chromosome is also not consistent cell to cell. Hotspots are 1-2kb regions that experience elevated recombination compared to neighboring genomic ...


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Immunity can be a double edge sword. It is aimed to detect and destroy invading pathogens but it can also target the self, as exemplified in autoimmune diseases. To avoid this, many failsafe mechanisms exists. For example, imagine an innocuous foreign antigen gets into your body and reaches the lymph node. There it may find a naive B cell that has a ...


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There is a lot of confusion and conflicting / imprecise definitions of these terms. It's biology after all :) A mitogen is an agent that causes a cell to enter mitosis. This definition is pretty clear, and there is a good consensus about it. (Well technically, mitosis is not the same as cell division, but we will gloss over this distinction.) The term ...


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You can find a great article about this here. basically, these two groups are very similar in their effects, however they work through different pathways. Mitogens directly promote cell to get through G1 checkpoint through highering the activity of cyclin D/cdk4 (the complex needed to get through the checkpoint.) and according to the article above, also ...


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In a healthy body, cells travel. But this is very dependent of the cell type. Some cell type will travel in all the body (lymphocytes, plasmocytes, etc) while other do not have any migration capability. The concept of diffusion is wrong to apply here, indeed the scales at which you are looking are not molecular. Moreover, there are very active mechanism ...


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Well, Sender, Fuchs, and Milo wrote a paper to discuss the total number of cells in the body and compare it to the number of bacteria in the body (http://dx.doi.org/10.1101/036103). Their discussion is quite in-depth. There are a number of ways to calculate it, but an interesting one involved calculating mammalian cell density by a study measuring the DNA ...


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The short answer: no. First, let's get an understanding of the cell cycle control system, as there are some important molecules involved in this system that regulate mitosis. Think of the control system as a series of stoplights: as you mention, there is one stoplight at the G2 phase. There are two additional checkpoints: one at G1 and one in the M (mitotic) ...


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There are species where cells and even whole organisms can go into a state called cryptobiosis where their metabolism is suspended but can be revived later. This usually happens when the conditions become too bad for survival (dry/cold etc.) and is reversed once the conditions improve again (rehydration warming up). One prominent and fascinating example are ...


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There's a decent presentation here that basically goes over what you're asking. As an inhibitor, azides are similar to cyanide in that they inhibit complex IV by binding cytochrome oxidase, resulting in a sort of chemical asphyxiation. Uncouplers are a little harder to wrap your head around. They embed in the membrane space, and we know that ETC and ...


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When physical damage to the cells occur a biological process called inflammation occurs. When inflammation occurs, white blood cells are rushed to the area in order to fight off any bacteria or harmful waste leakage from damaging the cells further. In order to get the white blood cells to the site of damage faster, the body induces a process called ...


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What we're basically looking at with ADC internalization Courtesy of Bayer So the way an ADC works: The antibody-drug conugate binds to a target antigen like a transmembrane receptor, the cell in response engulfs the entire complex and send it to an endosome. What the cell can do with the endosome depends on the cargo. Digressing, the ADC internalization ...


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The major hurdle for novel treatments to make it into humans is the assessment of its merits and added value over existing, proven treatments. And more importantly, the safety for humans has to be validated to a sufficient extent. The notorious from bench to bedside (Goldblatt & Lee, 2010) bottle neck. To answer your questions: Technically, going from ...


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AMP is first converted to ADP in the reaction AMP + ATP $\leftrightarrow$ 2 ADP catalyzed by adenylate kinase. So one phophate group is transfered from ATP to AMP, resulting in two ADP molecules. The ADP formed is then used to synthesize ATP as usual, by the mitochondrial ATP synthase or by the glycolysis enzymes. For other nucleotides and ...


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ATP burned per minute is not a useful number because the turnover is so high. 2000 kcal/day is dozens of kilograms of ATP so obviously ATP is turned over more than once a day, but there's probably more than one molecule of ATP being passed around between all the ATP synthases. This blog claims 250 grams. Taking the estimate of ATP concentrations(1-10 mM) ...


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From my Campbell's Biology textbook (Ninth Edition): Because of the orientation of tubulin dimers, the two ends of a microtubule are slightly different. One end can accumulate or release tubulin dimers at a much higher rate than the other, thus growing and shrinking significantly during cellular activities. (This is called the "plus end", not because it ...


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Actually, the answer is not obvious. @RoSiv gives the textbook case of symmetric cell division, where the two new cells can indeed be considered identical, and this is valid in many cases. But there are also cases of asymmetric cell division, where the "mother" and "daughter" cell are clearly different. In asymmetric cell division, the parent cell is ...


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Yes differentiation is primarily about using only a portion of the genome as you pointed out. However, differentiated cells possess a kind of "memory" which enables the daughter cells to continue the usage of the same set of genes. This "memory" is enabled by epigenetic mechanisms which leave inheritable "marks" on the DNA such as methylation (I won't ...


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If single cells are capable of surviving on their own then why did multicellularity evolve? This situation can be compared with the evolution of family and society, in a way; during the time of crisis, the survival chances increase when someone stays in a group. Similar conditions would have resulted in the evolution of multicellularity. The difference ...



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