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by Scrum V reporter Rick O'Shea
Fans go mad for new Warcraft game
Week 110 - hand anatomy
iPhone becomes top handset in U.S.
November 2008 Archives
November 27, 2008
November 25, 2008
November 21, 2008
November 20, 2008
Science
"Scientific research was the lifeblood of civilization; it was the one investment that could be guaranteed to pay dividends for eternity." From Earthlight, by A.C. Clarke.
November 19, 2008
November 17, 2008
Sponsor me!
This stupid moustache (under the stupid beard) has been cultivated for a couple of weeks now, so it's time for you lot to start donating! Me and the medical students are raising money for Prostate Cancer, so please donate some cash to make this worthwhile.
Click on this donate link and send some money please!
I don't think the right 'tache style has chosen me yet, so we'll have to wait and see how this thing turns out. You never know, I might keep it if you donate enough money... (at least until Christmas).
November 14, 2008
"I recognise that face", I thought, skipping through my Google Reader feed's articles (Google Alert, "Swansea Medicine"). I'm sure I've seen him on Monday mornings. November 13, 2008
Fans go mad for new Warcraft game
BBC Radio 1 Newsbeat are reporting on today's release of the new World of Warcraft update, The Wrath of the Lich King.
"World of Warcraft makes more money than the biggest Hollywood blockbusters every single month, has 11 million players and controls two thirds of the online gaming market, so when an expanded version was released, fans turn up in droves to be the first to get their hands on it."
There's a nice bit about the addictive nature of this fantasy world. "More than 3,000 people have joined an online support group called Warcraft Widows for relatives of addicted gamers.
"My wife started playing in 2007," according to one post. "She plays 12-18 hours a day and ignores all other life.
"She refuses to answer the phone. She refuses to return emails. I am destroyed by a video game and have no idea how to proceed."
"That kind of dedication has helped make World of Warcraft one of the biggest money-spinners in gaming history."
They haven't picked up on the game's nickname, World of Warcrack. I'm quite good - my copy of the Lich King isn't due to arrive until the weekend, ensuring I actually get some work done this week!
November 11, 2008
Week 110 - hand anatomy
This week I talked about the anatomy of the hand, and in particular the intrinsic muscles of the hand. The extrinsic muscles, the blood supply and the nervous innervation are largely covered elsewhere, and you need to link all these bits together.
I talked about how the tendons of the flexor digitorum superficialis and flexor digitorum profundus muscles insert ever so neatly into the middle and distal phalanges respectively, the superficial tendons splitting as they insert to allow the tendons of profundus to pass through them and onwards to the fingertips. These are the powerful muscles of the fingers, the muscles that allow us to hang from our fingertips when rock climbing or to transfer forces to jam jar lids. They're the "tendons" we see in the forearm of the Terminator when he cuts the skin away (image above). They're the wires we see in Luke Skywalker's forearm pulling his robotic fingers when the medical droid tests his fingertip sensation after his dad chops his hand off in The Empire Strikes Back.
The tendons of the extensor digitorum muscle on the dorsal hand act similarly, but to extend the fingers.
The intrinsic muscles of the hand are much smaller muscles contained within the hand and give us our amazing dexterity and control. Think of the tiny movements your fingers must make when writing with a pen, typing on a keyboard, or playing a guitar. The movements are very quick and very accurate, and are caused by a combination of muscle contractions by the extrinsic muscles, the muscles of the thenar eminence, the hypothenar eminence, the lumbrical muscles, and the interosseus muscles.
The muscles of the hand are named logically. In the thenar eminence (the fleshy bit at the base of the thumb) there are three muscles: abductor pollicis brevis, flexor pollicis brevis & opponens pollicis. You can review their actions and innervation from the elearning thingy link at the bottom of this article. Pollex means "thumb" in Latin, so you should be able to work out their functions. Each muscle attaches to carpal bones and the abductor and flexor muscles run to the proximal phalanx of the thumb. The opponens muscle attaches to the metacarpal bone, causing rotation of the carpometacarpal joint.
In the hypothenar eminence (the fleshy bit at the base of the little finger) there are also three muscles: abductor digiti minimi, flexor digiti minimi brevis and opponens digiti minimi. Their attachments are similar to those of the thumb, i.e. from carpal bones to the proximal phalanx, except for the opponens muscle that inserts along the metacarpal bone. Hopefully you can determine their actions from their names.
The lumbricals (Latin lumbricus = worm) pass from the tendons of flexor digitorum profundus and insert into the connective tissue "hood" that runs along the dorsal surface of each finger. (That's rather unusual for a muscle - not being attached to bone). When they contract they pull on that connective tissue on the back of the finger and extend the interphalangeal joints. That's great for pointing at things, or pushing your finger up when writing the upstroke of a letter "t".
The interosseus muscles are between bones (it's in the name). Specifically, they're between the metacarpal bones and there are two sets: palmar and dorsal sets. These muscles pass from metacarpal bones into the dorsal connective tissue hood of each finger. When they contract they will either abduct or adduct the fingers about the middle digit. The dorsal interosseus muscles abduct the fingers, and the palmar muscles adduct.
The anatomy of the hand is very detailed, and we had a very brief introduction to the musculoskeletal parts. You can review the movements of the hand, the muscles controlling the thumb, motor and sensory innervation of the hand, and link this to clinical tests using the hand using this elearning thingy created especially for you by some highly skilled students from the School of Digital Media at the Swansea Metropolitan University:
SDL: The Movements of the Hand
See also this article about the bionic hand that recently made Time Magazine's top 50 inventions after 20 years of development:
- Tom's Hardware
- Time Magazine
Week 109 - embryology of the musculoskeletal system
Last week I gave a lecture on the development of the musculoskeletal system, restricting the talk to the cells of the somites and the organisation of the cells of the limbs.
If you want to recap the lecture, you can listen to the podcasts in iTunes, or hear them here: ep5, somites; ep6 limbs.
November 5, 2008
Movember
I'm raising money for the prostate cancer charity. Do you want to find out how?
Go visit uk.movember.com for more info. Oh yeah, and donate some money!
Photos to follow, after you've all checked the link out.
Rainforest Fungus Naturally Synthesizes Diesel
Wired reports, "A fungus that lives inside trees in the Patagonian rain forest naturally makes a mix of hydrocarbons that bears a striking resemblance to diesel, biologists announced today. And the fungus can grow on cellulose, a major component of tree trunks, blades of grass and stalks that is the most abundant carbon-based plant material on Earth."
A fascinating find, especially given the implication that maybe crude oil wasn't formed in the way we thought it was. Is a new source of complex hydrocarbons for us to burn a good thing?
Week 109 - breast anatomy
In the last anatomy session I talked about the anatomy of the breast (or mammary gland), changes through life, and the similarities between the male and female breast. I started off by talking about supernumerary nipples, using James Bond's fake nipple as a bad example in the film, "The Man With The Golden Gun". I might have talked a bit of rubbish about Scaramanga, so for better information check Wikipedia: Francisco Scaramanga.
The major components of the breast are adipose tissue (fat), glandular tissue (mostly ducts) and connective tissue. The amount of fat determines the size of the breast, and the connective tissue determines the shape. The connective tissue sheets separating the glandular tissue into lobules form suspensory ligaments (or Cooper's ligaments) that attach to the anterior and inferior skin of the breast and to the posterior tissue. For most of the time the glandular tissue exists as a system of ducts that open individually at the nipple. The breasts are attached to the chest wall at the fascia overlying the pectoralis major muscles, and an axillary tail of the breast extends up towards the axilla, passing inferiorly to pectoralis major and piercing the deep fascia.
This link to the axilla explains some of the blood supply and lymphatic drainage of the breast. Most of the breast drains lymph laterally to axillary lymph nodes, which are often palpable and accessible to biopsy when concerned about the transfer of malignant cells from a breast mass. The medial parts of the breast drain fluid to parasternal lymph nodes, however, which are deep to the sternum and ribs. As we're mentioning breast cancer (but you will learn much more about this in other lectures) be aware of the potential involvement of connective tissue. With an inflammatory carcinoma, blockage of lymphatic ducts and oedema, the pull on the suspensory ligaments can be seen on the skin as a dimpling of the breast where the ligaments attach (peau d'orange).
Arteries pass to the structures of the superficial anterior thoracic wall from the axillary artery, and include the lateral thoracic artery, the thoracoacromial artery and the internal thoracic artery. These will all supply blood to the breasts and the muscles beneath, and are matched by veins draining to the axillary vein.
Before puberty the breasts of boys and girls are similar, and the duct system exists in both. With the hormonal changes of puberty (in particular, increased levels of oestrogens) the breasts develop in girls as a secondary sexual characteristic, largely due to increased depositions of fat here. The adult breast will change again with the onset of pregnancy, as the breast becomes prepared for feeding the newborn. The duct system lengthens and becomes surrounded by proliferating epithelial glandular tissue that will make the milk. The breast becomes larger, and the nipple will usually darken and also become larger. After weaning of the baby from breast feeding the glandular tissue of the breast will largely return to the pre-pregnancy state, and the size of the breast will be reduced. Changes to the nipple during pregnancy will also commonly revert to the pre-pregnancy state.
These changes to the tissue within the breast are all caused by particular hormones. As the same tissues exist in the male breast it is possible for these same changes to occur if stimulated by female hormones (see gynecomastia). Men, therefore, are also susceptible to breast cancer.
With the hormonal changes of the menopause, changes to the breast occur again. The glandular tissue will normally atrophy, and the secretory alveoli will disappear. The connective tissue will become weaker and more likely to stretch and the amount of adipose tissue in the breast may increase or decrease, causing marked changes to the shape and size of the breast.
For more information about breast anatomy, development, feeding, and so on, try visiting these websites:
- www.007b.com (extensive, layman's information about breasts)
- "Breastfeeding Does Not Create Sagging Breasts", American Society of Plastic Surgeons
- Breast Cancer, Cancer Research UK
