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Film Review The Structure and Metabolism of Lipids Dr E M Evans, University of Manchester. Available from Oxford Educational Resources Ltd, 197 Botley Road, Oxford. OX2 0HE, UK. F o u r colour videocassettes reviewed here deal with Lipid Structure (27, 21, 21 and 21 min): another four on Lipid Metabolism will be reviewed in the next issue.
Videotape 1: Simple Esters introduces the whole set and provides a classification of the lipids which forms the basis of the division of these four programmes. It becomes d e a r immediately that only mammalian cells will be considered: the tapes are directly orientated towards medical students. A constant feature is the attempt to make lipid structure and function 'relevant' to clLn_icalmedicine. The pace for the most part is faltly slow and students would find it easy to take notes but might find it a bit tedious at times. Dr Evans has a d e a r speaking voice with a neutral accent: her use of hand gestures is slightly annoying but not seriously so. The graphics (formulae and so on) are clear, but more use of colour would be helpful. However the proportions, lay-out and bond angles were not always pleasing to the eye and might not appeal to a chemist. F o r example when water molecules are shown, several different bond angles can be seen from 8 0 - 1 2 0 °. In the definition o f polar and nonpolar, which t o o k several minutes, nothing was said about water 'structure' although there was quite a lot on hydrogen bonding. In addition to the graphics, compounds are also shown as large-scale, rather floppy, space-filling models. These were helpful in understanding the shapes and flexibility of the molecules, and charged groups were easily picked out as 'red' atoms. The first film concluded with effective demonstration of why the b o d y stores triacylglycerol more efficiently than glycogen. This involved adding the same weights of a neutral oil, and of a polysaccharide (not actually glycogen, probably Sephadex or wall-paper paste) to a beaker of water. Each tape concludes with a summary of the main points. However, this is given orally and we are given little help in remembering the points. They could very easily have been written out and displayed, one by one. Videotape 2: Complex Esters starts by looking again at the classification scheme to remind us where we are. This tape deals with phospholipids and glycolipids. The formulae are now given in 'shorthand' form and in the first five minutes there was a lot o f chemistry with very little about function. Medical students might well find this offputting. Following a definition of 'amphipathic' and an account of protein-phospholipid interactions, the first functional aspect to be dealt with is the transport of trigiyceride in the blood. Although this was clear, it did not emerge how little protein there is in a chylomicron. After this, two 'theories' of cell membrane structure were offered with explanation of how they might function. Both referred to lipid-in-a-protein-sandwich type of structure and students might find them difficult to reconcile with pictures they may have seen in textbooks or Scientific American of protein icebergs floating in a sea of lipid bilayer. A disappointing part this, and an opportunity missed. (Students used to playing 'Space Invaders' will be amazed and impatient at how slow the graphics move!). Videotape 3: Other Complex Esters (why not say that this tape deals with cerebrosides and gangliosides and essential fatty acids?). This tape starts with chemistry, but the structure of sialic acid is flashed up for about 2 sec (couldn't have understood it in the time) in order, it seemed, to talk about lipidoses. There was little about the function of glycolipids, or about their structures for that matter. BIOCHEMICAL
EDUCATION
11(2) 1983
The next section deals with unsaturation. The pace here is quite slow and students would very easily follow this. Both the 6o and A systems of nomenclature are given, and as the programme continues the 6o system seems to be favoured, until we get to the prostaglandins when we find ourselves back with the A system. This is an area that always confuses/annoys/bores students and it might have been better to have taken a very firm fine one way or the other. However, the essential fatty acids and their role in prostagiandin formation were clearly described here. A demonstration in this section compared butter with cooking oil. Lard or dripping would have been better examples than butter, both from a chemical point of view and on the basis of fatty acids of C 16 or C 1 s - c h a i n length being the only important ones in mammalian cells (stated in tape 1).
Videotape 4: Non-esters. Again not a very helpful title. This tape deals with fat-soluble vitamins and steroids. In fact vitamins are only dealt with briefly. The definition of 'vitamins' was rather primitive, but an important point brought out was how much we depend on gut flora for supplies of vitamins and the consequences of oral antibiotics. It was said that we eat 'tons' of food but only need 'ounces' of vitamins: would it not have been more appropriate to be metric! The discussion of Vitamin E was honest. The section on steroids and cholesterol started out with atherosclerosis and statistics, clearly designed to appeal to future medics. The graphics here were quite good and there was sensible discussion of the controversy about diet. (More food products could have been shown here to help the interest along.) After a very brief mention of the role of cholesterol in membranes we are on to modification to the steroid nucleus to give steroid hormones and bile salts. The graphics dealing with ring numbering and modification were very effective here. However, in the bile salt part we were not told the structure of giycine (should know it?), or of taurine (probably wouldn't know it). This of course leads on to a brief consideration of the digestion of fat. Finally we are reminded that we have been told the absolute minimum and that we must use our lecture notes and the recommended t e x t b o o k (she doesn't say which this is). Our overall feeling was that the presentation was clear, and, accepting the bias towards medical students, reasonably balanced and comprehensive. The most worrying feature was the variability in pace, some parts being really leisurely, others being rushed. It did not seem as though this was being done to get to the 'medically relevant' parts as quickly as possible. On the whole the pace and clarity was such that the programmes would be understood quite easily even by those whose first language is other than English.
New Publication Trends in Biotechnology will appear in May 1983, advertised as the only Review Magazine for biotechnologists. Further information from Elsevier Biomedical, P O Box 548, Amsterdam, The Netherlands. Subscription rates: Personal rate $37 (5 issues in 1983), Institutional rate $108 (5 issues plus handbound reference issue) including delivery by air where appropriate. Obituary We record with regret the death o f Sir Rudolph Peters on 28th January 1982 at the age o f 92 after almost 62 years o f active research in biochemistry. Sir Rudolph became Whitley Professor o f Biochemistry in Oxford 1923. Although he retired from Oxford in 1954 he continued to work in Cambridge, for five years in Babraham and then in the Biochemistry Department until 1976.
Film Review The Structure and Metabolism of Lipids Dr E M Evans, University of Manchester. Available from Oxford Educational Resources Ltd, 197 Botley Road, Oxford. OX2 0HE, UK. F o u r colour videocassettes reviewed here deal with Lipid Structure (27, 21, 21 and 21 min): another four on Lipid Metabolism will be reviewed in the next issue.
Videotape 1: Simple Esters introduces the whole set and provides a classification of the lipids which forms the basis of the division of these four programmes. It becomes d e a r immediately that only mammalian cells will be considered: the tapes are directly orientated towards medical students. A constant feature is the attempt to make lipid structure and function 'relevant' to clLn_icalmedicine. The pace for the most part is faltly slow and students would find it easy to take notes but might find it a bit tedious at times. Dr Evans has a d e a r speaking voice with a neutral accent: her use of hand gestures is slightly annoying but not seriously so. The graphics (formulae and so on) are clear, but more use of colour would be helpful. However the proportions, lay-out and bond angles were not always pleasing to the eye and might not appeal to a chemist. F o r example when water molecules are shown, several different bond angles can be seen from 8 0 - 1 2 0 °. In the definition o f polar and nonpolar, which t o o k several minutes, nothing was said about water 'structure' although there was quite a lot on hydrogen bonding. In addition to the graphics, compounds are also shown as large-scale, rather floppy, space-filling models. These were helpful in understanding the shapes and flexibility of the molecules, and charged groups were easily picked out as 'red' atoms. The first film concluded with effective demonstration of why the b o d y stores triacylglycerol more efficiently than glycogen. This involved adding the same weights of a neutral oil, and of a polysaccharide (not actually glycogen, probably Sephadex or wall-paper paste) to a beaker of water. Each tape concludes with a summary of the main points. However, this is given orally and we are given little help in remembering the points. They could very easily have been written out and displayed, one by one. Videotape 2: Complex Esters starts by looking again at the classification scheme to remind us where we are. This tape deals with phospholipids and glycolipids. The formulae are now given in 'shorthand' form and in the first five minutes there was a lot o f chemistry with very little about function. Medical students might well find this offputting. Following a definition of 'amphipathic' and an account of protein-phospholipid interactions, the first functional aspect to be dealt with is the transport of trigiyceride in the blood. Although this was clear, it did not emerge how little protein there is in a chylomicron. After this, two 'theories' of cell membrane structure were offered with explanation of how they might function. Both referred to lipid-in-a-protein-sandwich type of structure and students might find them difficult to reconcile with pictures they may have seen in textbooks or Scientific American of protein icebergs floating in a sea of lipid bilayer. A disappointing part this, and an opportunity missed. (Students used to playing 'Space Invaders' will be amazed and impatient at how slow the graphics move!). Videotape 3: Other Complex Esters (why not say that this tape deals with cerebrosides and gangliosides and essential fatty acids?). This tape starts with chemistry, but the structure of sialic acid is flashed up for about 2 sec (couldn't have understood it in the time) in order, it seemed, to talk about lipidoses. There was little about the function of glycolipids, or about their structures for that matter. BIOCHEMICAL
EDUCATION
11(2) 1983
The next section deals with unsaturation. The pace here is quite slow and students would very easily follow this. Both the 6o and A systems of nomenclature are given, and as the programme continues the 6o system seems to be favoured, until we get to the prostaglandins when we find ourselves back with the A system. This is an area that always confuses/annoys/bores students and it might have been better to have taken a very firm fine one way or the other. However, the essential fatty acids and their role in prostagiandin formation were clearly described here. A demonstration in this section compared butter with cooking oil. Lard or dripping would have been better examples than butter, both from a chemical point of view and on the basis of fatty acids of C 16 or C 1 s - c h a i n length being the only important ones in mammalian cells (stated in tape 1).
Videotape 4: Non-esters. Again not a very helpful title. This tape deals with fat-soluble vitamins and steroids. In fact vitamins are only dealt with briefly. The definition of 'vitamins' was rather primitive, but an important point brought out was how much we depend on gut flora for supplies of vitamins and the consequences of oral antibiotics. It was said that we eat 'tons' of food but only need 'ounces' of vitamins: would it not have been more appropriate to be metric! The discussion of Vitamin E was honest. The section on steroids and cholesterol started out with atherosclerosis and statistics, clearly designed to appeal to future medics. The graphics here were quite good and there was sensible discussion of the controversy about diet. (More food products could have been shown here to help the interest along.) After a very brief mention of the role of cholesterol in membranes we are on to modification to the steroid nucleus to give steroid hormones and bile salts. The graphics dealing with ring numbering and modification were very effective here. However, in the bile salt part we were not told the structure of giycine (should know it?), or of taurine (probably wouldn't know it). This of course leads on to a brief consideration of the digestion of fat. Finally we are reminded that we have been told the absolute minimum and that we must use our lecture notes and the recommended t e x t b o o k (she doesn't say which this is). Our overall feeling was that the presentation was clear, and, accepting the bias towards medical students, reasonably balanced and comprehensive. The most worrying feature was the variability in pace, some parts being really leisurely, others being rushed. It did not seem as though this was being done to get to the 'medically relevant' parts as quickly as possible. On the whole the pace and clarity was such that the programmes would be understood quite easily even by those whose first language is other than English.
New Publication Trends in Biotechnology will appear in May 1983, advertised as the only Review Magazine for biotechnologists. Further information from Elsevier Biomedical, P O Box 548, Amsterdam, The Netherlands. Subscription rates: Personal rate $37 (5 issues in 1983), Institutional rate $108 (5 issues plus handbound reference issue) including delivery by air where appropriate. Obituary We record with regret the death o f Sir Rudolph Peters on 28th January 1982 at the age o f 92 after almost 62 years o f active research in biochemistry. Sir Rudolph became Whitley Professor o f Biochemistry in Oxford 1923. Although he retired from Oxford in 1954 he continued to work in Cambridge, for five years in Babraham and then in the Biochemistry Department until 1976.