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Embryology 9/12/2017

chromosomal abnormalities. trisomy is an extra chromosome and monosome missing 1 chromosome. ie there should be chromatids that form a chromosome. if 3 single chromatid chromosomes join together instead of the usual 2, this is called trisomy, and if one chromatid does not meet with a second to form a 2chromatid chromosome this is monosomy. the 3 mentioned trisomy defects are numbered by which chromosome it would affect when you do that thing that spreads them out acording to acidity or whatever that experiment you did in biomolecular science class. so trisomy 21 is downsyndrome, trisomy 12 is patau syndrome, and trisomy 18 is edward syndrome. there is another syndrome that is sex dependent that he rapidly mentioned which was klinefelter vs turner syndrome. please check these out before the exam. the teacher starting talking about oogenisis. he said diploid 2n23 before meiosis 1, then meiosis 1, then halploid n23. then meosis 2 for a total of 4 cells. after a female is 35-40 y/o the rate of chromosomal abnormalities drastically increases. and requires charyotyping to check the chromosomes. this method is called FISH and that stands for something i forget. this is performed via aminocentesis? or draining a bit of fluid from the amniotic sack. this works because their is DNA is skin cells. and because the fetus’s skin isnt fully developed some of the skin cells are freerly floating in the amniotic fluid.  the tip of the chromosome is the telomere. the 4 subsections that i mentioned from yesterdays class, little zebras play dominos was the correct lettering and those letters stand for leptotene, zygotene, pachytene, and diplotene. spermatogenisis starts at puberty unlike oogenisis which starts intrauterine life of the fetus. it starts at the 3rd month of pregnancy and ends at 7 months. next the teacher outlined major steps of spermatogenisis.  oogenisis ends at the end of phrophase 1 at end of the diplotene step and does not continue like spermatogenisis. the oocytes remain dormant from the end of diplotene and stay dormant until puberty.  ampulla means dialated and is the largest part of the fallopian tube which is right outside the ovarie with the fibere, or finger like projections. the istimus is the narrowest part of the fallopian tube and is the area that attaches to the uterus. the uterus has 3 layers and the teacher told us to concentrate on the innermost layer because that is the ‘functional layer.’ its the layer that swell, sheds, the placenta attaches too, its the functional layer. its highly vascular with an embomidral glands? the internal os vs the external os is the opening of the cervix and internal is inside the uterus, external closer to the vaginal canal. next he reviewed the menstral cycle which totals 28 days. the first stage is the follicular, goes from 1-14 and includes menses which is days 1-5. then the 2nd stage is the luteal phases which occurs between days 14-28? theres a gap in there somewhere? and this all needs to be clearified and studied before the test. the corpus leutium gives meaning to the luteal phase. its an empty follicule? and secretes progesterone. progesterone maintains proliferated endomyetrium. the corpus letium releases progesterone for 3 monts if fertilization occurs, but then from 3-9 months the placenta takes over the release of progesterone. i am unsure but if i remember right from nursing school i am pretty sure the corpus leitium becomes the placenta? idk remember to lookup placenta’s origin of creation.

[themedicineprof-blog]

Histology & Cellular Biology 9/12/2017

yesterday in histology&cell bio we covered the term microtome, which is the tool used to slice samples for placement on a slide. histochemistry is when chemicals react with tissues compared to immunohistochemistry when antibodies react with tissue. we covered the preperation of a sample for histology which was extremley boring and doesnt seem to be very high yield for the USMLE. so... anyways the first step is sampling, or slicing the tissue. the second step is fixation and is to preserve the sample. this can be either chemical or physicial. chemical can be simple or complex. a simple type of chemical fixation is with formaldehyde and a complex is with bour? fluid? physical fixation is freezing. some reasons you might use freezing is to preserve enzymes (they would die during chemical fixation) or if the sample needed to be reviewed rapidly for diagnostic purposes, perhaps an infectious disease outbreak of a scary zombie virus.  the third step is dehydration. dehydration is performed with several increasing concentration steps of alchohol exposure. the fourth step is clearing and this is done to remove the alchohol using xylene in order to prevent a hazey or unclear sample. ie clearing. the fith step is infiltration or impregnation. the purpuse is to incrust the sample for easy cutting. parafin is usually used this takes 12-16 hours and is done by heating the parafin to a melting point, and submerging the chemical, then allowing it to cool. embedding occurs between steps 5 and 6. the 6th step is sectioning, and is 3-10 micrometers using a microtome which uses a steel blade.  physicial fixation or freezing skips steps 3-6. step 7 and 8 is a second round of dehydrating and clearing and this is performed to make the sample appear clear. the instructor showed us an image of what the sample looks like if you do or do not dehydrate and clear the sample a second time and it was very unclear, so its important to do this twice. step 9 is staining and the purpose of staining is to differentiate structures. H+E is the most common staining chemical. **please review which H or E targets acidophiles or basophiles. step 10 is the final step and is mounting.  all of this process is for samples that are structured, or solid. for liquid samples, the process is called smearing. in this process, no sectioning occurs.  you collect, smear, fix, stain, check, and coverslip. the most common stain is Giemsa. fixation takes 3-5 minutes using alchohol. an additional staining method is the romanowski staining method and this is for electron microscopy. electron microscopy produces a highly detailed, but all black and white image.   it uses an electron beam to view things less than 1micrometer. because the normal micrometer can only cut as thin as 3 micrometers, an ultramicrometer is used which has a diamond or glass knife. it cannot use parafin to encrust the sample because it needs a stronger structure to cut thinner. double fixation occurs which is G then O? and lastly for electron microscopy, the tissue must be fresh.

staining can be done with acidic or basic dies. the teacher made a HUGE over generalization about acophilic vs basophilic things and said “if it is acophilic then it is a base and has a positive charge, and if it is basophilic it is an acid and has a negative charge.” i spent alot of time checking the electral charges of these  things and found that that is not always the case. pKa is the strength of an acid or a base and pKa determines the pH of the surrounding enviornment that would protinate or deprotinate the acid or base. ie 1pKa would add one proton, 2pKa would add 2 protons, and so forth. so this generalization seems to be assuming the following: considering if the substance was placed into a solution of all pH values, if the substance was an acid, more often than not it would be stronger than the surrounding enviornment, and lose a proton. thus having a negative charge. as far as the H+E method mentioned earlier. H is hematoxylin is blue, and is basic so it stains things that are basophilic. things that are basophilic are acidic and include DNA, RNA, and the rough ER. Eosin is the acidic dye and stains things acidophilic things pink. things that are acidophilic are things that are basic and include the cytoplasm, proteins, and membranes.

[themedicineprof-blog]

Anatomy 9/12/2017

Yesterday in anatomy we covered very basic anatomy terminology. Some of the words I didn’t know were: Profundal, which means deep (opposite of superficial). Ipsilateral vs contralateral which mean the same side vs different side respectively. The teacher explained to us that we need to be able to look at an MRI and determine which plane it is showing, in other words, the directions of slices the image were taken in. The sagittal or medial plane divides the body left and right, running vertically. so a sagital brain scan would start by slicing off the ear. Coronal divides anterior and posterior sections so it would start by slicing off the nose. And lastly, transverse runs horizontal, separating superior and inferior so it would start by slicing off the bottoms of your feet. a few words I knew but avoided using on documentation because of lack of strength were ventral (meaning anterior) and dorsal (meaning posterior) the dorsal of the foot is the top. the ventral part of the lower arm is the hairless, (bottom) half of the forearm, and the dorsal part of the arm is the hairy part of the forearm. Lateral is the opposite of medial. cephalic is a synonym for superior, and caudal is a synonym for inferior. proximal and distal are only properly used when referring to the extremities. saying someone has an abdominal scar, proximal to the midline on the right side is incorrect. the correct term would be lateral. medial and lateral are used for the trunk and head. proximal and distal are used for the extremities. abduction vs adduction. abducted by aliens means to be taken away, abducting your arm is to move it away from your body. the anatomical position of the arms is pronation. unsure at this time: check later** inversion vs eversion, I know it is the movement of tilting your foot inward vs outward, unsure which is which.  langers lines are collagen fibers that they cut across for a masectomy, making a semi circle around the breast rather than a straight slice in order to minimize scarring.

next he talked about the lymphatic system and explained how the left side of the lymph system collects LLE, RLE, LUE, and left section of head/trunk.  the left side of the thoracic duct of the lymphatic system collects in the lower abdomen and around the left jugular, depending on if its coming from the upper body or lower body.  the thoracic duct starts collecting just above the L1 region of the spine. remember, Lymphatic duct, L1. on the other hand the right lymphatic duct only collects the RUE and right jugular. the most inferior part of the lymphatic thoracic duct is the cysterma chyll. both right and left upper thoracic duct collects at the joining site of the crachiocephalic, subclavian, and jugular known as... veous angle? the staging of cancer is done through TNM tumor, nodal, metasis.  the common staging of cancer is the nodal section. this depends entirley on how many lymph nodes are affected but is not the only way cancer is staged. Tumor has to do with the size/number of tumors. and metasis depends if its local or metasicized. ie if only a local lymph nodes are affected this is different than if no local lymph nodes are affected but a single further away lymph node is affected.  The teacher told us it is very important to know which lymph nodes would be swelling if different parts of the body were affected. IE if he asks if someone has cancer of the hand, which lymph node would it drain to. vs breast vs any other place if cancer originates from.  he explained that their are 2 cancer routes of metasis. lymphatic vs haematogenisis. lymphatic is the most common route for carcinomas where as haematogenisis is the most common route for sarcomas.  review the 3 differences in the tissues of muscle types. ie the striations whether they are present in muscular as well as cardio, or if cardio is not striated like smooth muscle?? intresting fact, muscles are larger the further away from the target moving piece. ie if ur trying to move ur elbow, the bicep is the acting muscle and its larger towards the shoulder.

[themedicineprof-blog]

Histology & Cellular Biology 9/11/2017

very little information was covered in class today. instead, the teacher mostly focused on outlining her expectations of the students. she asked a few questions, most of them were very simple, like ‘what is the conductive system in the heart.’ one that i wasnt 100% sure of the answer, and none of the students answered correctly was ‘how many different types of cells are in the body?’ and she said the answer was about 200. now i dont know if this is referring to all the different ‘cell types’ that include how a cell is renamed during different stages of development, or what. perhaps if you wrote down the name of everything that was “_____ cell” or counted the number of entries in the glossary, you might count about 200. i am still skeptical of this overgeneralization. first she said we had 4 different types of tissue, then she said 5 so I will have to be careful with this professor. I hate being presented inaccurate information so I wish she would speak more carefully. anyways the FIVE! FIVE! types of tissues she listed were muscle, nervous, blood, and connective. dammit! i only wrote down four!!!

[themedicineprof-blog]

Embryology 9/11/2017

despite the instructor constantly insisting we did not need to take notes today, a pretty sizable amount of information was covered. the instructor first informed us that Embryology in this course would be divided into two main sections. General Vs. Systemic. From what I understand, the areas kind of overlap, because general embryology will include all of the basic systemic embryology information. in other words, systemic embryology will be much more detailed information only involving a single body system, while general will focus on the big picture and the relationships between all of the body systems. the difference between the two still seems a bit unclear to me.  the instructor began with a very basic but much-needed embryology overview. He began by defining Gamate (sex cells egg sperm oocyte). He revealed to us that he has a pet-peeve of an oocyte being called an ovum. he told us never to call it an ovum, only to call it an oocyte. but khan academy calls it an ovum and i like those guys. He explained to us that a fertilized egg is called a zygote. and eventually, the zygote develops to become an embryo. From there, he began talking about cell division. he outlined similarities and differences between mitosis and meiosis. His choice of wording was that: mitosis is cell division throughout the entire body that results with an increasing number of cells. And meiosis results in a decreased number of chromosomes and is for sexual reproduction. He reminded the class that the typical number of chromosome in somatic cells (cells not involved in sexual reproduction) is 46 pairs or 23 sets. because this was a general overview he bounced around back and forth a bit between sexual reproduction and cellular division, for the sake of following my notes i am going to follow the chronological order of presentation. He defined the process of the sperm meeting the egg as uniting. a khan academy video I watched earlier this morning mentioned that 2-3million sperm competes in uniting, so that is worth noting. The instructor said that ‘before uniting, the chromosomal number is decreased from 23 pairs to 23 halves. he also stated that meiosis only occurs in gametes. he continued ‘gametes have a preparation phase which is three steps.’ G1 - S - G2 ‘ where g stands for growth and s stands for synthesis. he said ‘sytnthesis makes a copy.’ following G2 is meiosis1 and then meiosis2. so g1-s-g2-m1-m2. Then he said meiosis has 4 stages: prophase, metaphase, anaphase, and telophase. and a subscript following the name of the sub stage will identify if its referring to m1 or m2. ie: prophase1.  he made the next infomration seem to be very important.. M1 prophase has 4 substages (all of which i was unfamiliar with, I couldnt read the board or understand his accent, so I am watching khan academy to get that information more clearly explained to me after this). i believe the first letter of each substage was L Z P D. little zebras playing dominos :) but that could be wrong lettering so we will see. After that fairly indepth review of cellular division stages he goes back into more familiar territory and starts reviewing ‘chromosomes are tightly packed within the nucleus, during division, chromosomes unwind and spread out or uncoil. they become more ‘prominent (his words) and the nuclear membrane begins to degrade. centrioles align along the middle of the cell and the nuclear membrane degenerates the centrioles spread from 1 side to the other (seperating the halves of the chromosomes?) he defined the terminology for the center where the centrioles align, however it was a word I couldnt remember, or understand with his accent so I should look into that if Its not covered in khan academy. epitorial line? then he continued on by explaining the differences between meiosis 1 and meosis 2. meiosis 1 results with 2 daughter cells, and meosis 2 results with a total for 4 daughter cells. so it seems to be they are pretty much the same? it just happens twice. he defined spermatogensis (formation of sperm) and oogenesis (formation of oocyte). he explained that in spermatogenisis, at the end of meosis 2 had a total of 4 sperm cells. this leads me to deduce that spermatogenisis includes the g1-s-g2-m1-m2 that was discussed earlier. he explained that unlike in spermatogenisis, when discussing oogenesis, only 1 egg is produced (and 3 other cells of a different type???)  then he said *the most important thing for us is stage 3 of the m1 prophase, and if my acronym about little zebras playing dominos is correct, then that would be the P word. he defined diploid and halploid, 23 pairs, 23 individual chromosomes respectivley.  he said *the most important thing about substage 3 (dominos) of m1 prophase is that during this time, the 23 maternal and paternal halploids unite. he said this uniting process can either be called unite, synapse, or junction. so involving this most important topic, he said  when no seperation occurs at this time when it should have it is called a nondisjunction. disjuntion is the seperation and this normally happens in M1 prophase substage 3. this is clearly a high yield area to focus on studying when it comes time to review for the exam, make sure to focus some extra time on this specific topic. when nondisjuntion occurs in this m1 prophase substage 3, the result may be downsyndrome, if the zygote? (not sure if its a zygote at this stage) if it has 21 chromosomes on one side, and 23 on the other, rather than 23 on each side. a similar complication is called ?Microdition? (couldnt understand accent) but this is when a small part of the chromosome goes from 1 side to the other. something related is a word like cribucha???  he said that the area he defined as the most important area to us is the most important BECAUSE, most chromosomal abnormalities occur during this stage 3 of m1 prophase. it seems that the cell is considered a zygote at this time because he said the following two terms were synomyms. zygote abormalitiy and chromosomal abnormality. the majority amount of chromosomal abnormalities do no survive, resulting in sponatneous abortion. and that the majority of spontaneous abortions are due to chromosomal abnormalities. thats about where he left off. Ill try to watch as many khan academy videos before class on the areas I was unclear in, and may leave a  follow up post if I have time.

[themedicineprof-blog]

Anatomy 9/11/2017

today was primarily an introduction. No information was covered in anatomy today. instead, the instructor focused on outlining his expectations of the students. The instructor requested that each student create a study calendar, and he stated that we will be expected to present him our study calendars to him in a one-on-one closed door meeting between the student and the professor in about two weeks.  For my calendar and study plan, I think I might plan on going to sleep immediately each day after school, to absolutely ensure I get around 8 hours of sleep each night. Then each morning I can self-study for about 6 hours before classes begin. This way, once I can no longer keep myself motivated to study, the instructors will be there for me to force more knowledge down my throat. I would like to begin preparing for the NBME of each class. My schedule might look something like this: Total 6 hours. 3 courses, 2 hours each. 30 minutes of previous day’s class review, and reviewing all previous notes. 30 minutes of new knowledge familiarization for next class 30 minutes of NBME questions and answer rational review 30 minutes of relevant topic khan academy video lessons I want to try to avoid spending an unbalanced amount of time on different subjects, even if I feel that I am unfamiliar with them. perhaps on saturday or sunday I can dedicate a 4 hour time block to specifically study areas that I am struggling with. This will ensure I dont underestimate the difficulty of one particular area. It is important to improve all the areas of study, not just the weakest areas. ill probably make an excel calendar or something later this week. 

[themedicineprof-blog]

first homework assignment  [50 points]

answer each question with as few sentences as possible        (1) outline an environment [10 points]      (2) explain a problem [10 points]      (3) suggest a solution  [20 points]      (4) identify pros of the solution [5 points]      (5) identify cons of the solution [5 points]

.................................................       (1) outline an environment [10 points] ................................................. 

patients prefer to be cared for by familiar MeDICAL professionals

.................................................       (2) explain a problem [10 points] ................................................. 

MeDICAL professionals are occasionally assigned to care for unfamiliar patients

.................................................       (3) suggest a solution ................................................. 

familiarize each MeDICAL professional with each patient by rotating assignments

.................................................       (4) identify pros of the solution ................................................. 

patients will always be cared for by familiar MeDICAL professionals

................................................. 

     (5) identify cons of the solution .................................................

familiarization would be prolonged

[themedicineprof-blog]

Hey! Wait!

Don’t go out! That was close! MeDICINE can be dangerous! You need to study MeDICINE first, for the protection of yourself and your patients. I know! Here, come with me! ... Let me think... Oh, that’s right. I told you to come! Just wait! Here, PLAYER! There is a school here! Haha! MeDICINE is taught inside the school. When I was young, I was a serious MeDICAL student. In my old age, I only have a few books left, but you can have one! Choose! ... Be patient! RIVAL, you can have one too!

...

Now, PLAYER, which book on MeDICINE do you want?

So! You want that book,

That book is really energetic!