Surgical Scalpels

Today the majority of surgical operations in the NHS require a scalpel for incisions and other operations. It is perhaps one of the most important instruments a surgeon possesses yet to most of us it is nothing more than just a sharp blade. A scalpel is typically a small, thin and very sharp knife used predominantly for surgical operations and dissections. There are two parts to any scalpel, the handle and the blade. In the past, various sharp materials have been used for scalpel blades such as the obsidian blade (a volcanic rock) and glass, however, the main material in use today is martensitic stainless steel. In an interview I conducted with a general surgeon from Kings College Hospital, I explored the various properties required for a scalpel. Unsurprisingly, the ones which came up were weight, sharpness, shininess and corrosion resistance. Corrosion resistance is a standard property for any surgical instrument and a shiny blade allows the surgeon to see the point at which he is cutting. A heavier scalpel gives the surgeon more control but there must be a playoff between control and practicality when considering what would make the ideal scalpel.

Stainless steel – the material used for the blade of the scalpel – is an alloy, which is a metal made by combining two or more different metals to enjoy superior characteristics such as increased strength and corrosion resistance. There are five different grades of stainless steel. Identifiable by their different microstructures, they have different properties due to the balance of their constituent elements e.g. Chromium gives varying resistance to corrosion, nickel helps with ductility and increases the strength of the material, as does carbon. Martensitic steels contain from 12 to 18% chromium, 2% nickel and about 1% carbon. Martensitic steels are chosen due to their adequate corrosion resistance and ductility, which allows them to be shaped into the blades as well as their strength after being quenched.

The scalpels used in NHS hospitals are either disposable or reusable. The disposable ones are less common and are only used in minor theatre whereas the reusable scalpels are used for large scale operations in major theatre. The difference between the two is the handle, although the size of the blade may also vary depending on the requirements of the operation. Reusable scalpels have a stainless steel handle whereas disposable scalpels have plastic handles. However, due to health and safety issues, the blades of the reusable scalpels are never reused. The training required and the potential for injuries in the cleaning blades means that it is not only economically beneficial to buy new blades but also safer to do so. The stainless steel handles are sterilised and reused.

The whole surgical process has evolved over the years and stainless steel scalpels seem to be where we are at now. However, it is widely believed that the future holds something very different for surgery. Femtosecond lasers are considered to be the most advanced form of carrying out surgery in the 21^st Century. A femtosecond is one quadrillionth of a second (10^-15seconds). Femtosecond lasers produce very brief, high-energy light pulses that can sear targeted tissue so quickly and accurately that the lasers’ heat has no time to escape and damage nearby healthy cells. It gives surgeons the ability to operate on a micron scale, which is why lasers are mainly used in eye surgery. 

The potential of Flavonoids in curing Alzheimer’s Disease

Alzheimer’s Disease is a incurable neurodegenerative disease, causing loss of memory and basic communication skills and currently effects around 465,000 people in the UK alone. During its course, protein “plaques” form as well as tangles in the brain which lead to the death of brain cells. It is therefore a progressive disease which eventually kills enough brain cells to aggravate its symptoms. Thus far, scientists have not identified on single cause for Alzheimer’s Disease, instead attributing it to a variety of factors. However, recent research has shown that there is a clear link between oxidative stress and the Aβ plaques. In this essay, I shall explore the potential for Flavonoids in curing Alzheimer’s Disease.

First of all, we must familiarise ourselves with what Flavonoids are - a family of plant secondary metabolites which have anti-inflammatory and anti-oxidant properties. It is also thought to be an Aβ inhibitor. Theoretically all of these properties would be ideal for curing Alzheimer’s, which is why so much research is going towards investigating the potential for using Flavonoids in combating neurodegenerative diseases. However, as we shall find out later, although some molecules exhibit desirable properties in vitro, these may not necessarily be the same in vivo. Amongst the several factors which have been identified as having an effect on neuronal function are oxidative stress and inflammatory stresses.

As an anti-oxidant, Flavonoids could potentially help prevent the onset of the disease. A study carried out at the Erasmus Medical Center in Rotterdam, Holland, of over 5,000 patients over the age of 55 during which 197 people developed Alzheimer’s. Amongst them were smokers who by smoking increased their chances of getting Alzheimer’s Disease. However, the study showed that out of the smokers, the ones who took vitamin C or E supplements were less likely to develop Alzheimer’s due to the antioxidants acting on the intermediate free radicals. Although this, along with very many other studies were largely inconclusive, a clear link was established, showing that Alzheimer’s Disease may be prevented by the action of anti-oxidants.

Further studies have shown that oxidative stress precedes the deposition and formation of Amyloid βeta plaques which characterize Alzheimer’s disease. In one of these studies, there was a clear link between the build up of APP (amyloid precursor protein) – which results in blockages and tangles in the brain - and excess Aβ deposition and oxidative stress.  It has been hypothesised that flavonoids, present in green tea are Aβ inhibitors and could perhaps serve a role in preventing Alzheimer’s in this way as well. All of the above suggests that there is in fact great potential for Flavonoids in the field of medicine in not only preventing but also curing neurodegenerative illnesses such as Alzheimer’s. However, having read and scrutinised many research papers, it is my contention that placing such hope in Flavonoids is somewhat premature.

 Flavonoids are known to be antioxidants and would therefore theoretically be the ideal cure. Antioxidants work by neutralising the intermediate free radical in oxidation reactions in the body by donating one of their own electrons to end the process of “stealing” which occurs in the free radicals. In our bodies, Vitamins C and E serve as the main antioxidants and flavonoids were found to be more powerful antioxidants in vitro. However, their action in vivo differs significantly from in vitro. Unfortunately, a study by the Linus Pauling Institute and the European Food Safety Authority  concluded that flavonoids inside the human body have no benefit as far as antioxidants go, as they are poorly absorbed, with less than 5% being absorbed. Therefore, it seems that flavonoids may only be able to combat Alzheimer’s through its anti-inflammatory properties.

Despite the poor absorption of Flavonoids in the human body, one can’t ignore the increase in the antioxidant properties of the blood after consumption of flavonoid rich food products. Although unclear, it is thought that this most likely derives from the increased production of uric acid to excrete flavonoids from the body, as they are recognised as foreign by the body and immediately excreted. Therefore it seems unlikely that we they have an effect as antioxidants. As far as their Aβ inhibiting properties go, I am equally pessimistic. The research paper I read which showed that it had a role in inhibiting the production of Aβ had one major flaw in that it had not isolated flavonoids completely and had instead found that green tea had this effect. Green tea also happens to contain Luteolin – a known Aβ inhibitor - and until research comes out proving that flavonoids can serve such a purpose by themselves, it would be wrong and naive to think that they are Aβ inhibitors. However, one undeniable property of flavonoids is its anti-inflammatory properties for beta amyloid stimulated proinflammatory responses. However, this alone does not make it some sort of miracle compound as there are other anti-inflammatory compounds which exist and are used such as CNI-1493, a drug used in a collaborative research assignment between german and American researches showing that it targeted amyloid beta plaques.

Therefore to conclude, flavonoids could potentially be the cure to Alzheimer’s and many other neurodegenerative diseases such as Parkinson’s and Creutzfeldt-Jakob disease in the future. However, at present, although they manifest the ideal properties in vitro, they are not very effective in vivo, which is what matters. Perhaps in the future, a suitable medium can be used to help in the absorption of flavonoids in the human body and perhaps one day flavonoids can be shown to be Aβ inhibitors. However, what cannot be ignored is that flavonoids are recognised as foreign by the body and cause a reaction – something which must be negotiated around – as they are also present in compounds such as celery, which very many people are allergic to.

References:

Flavonoids: chemistry, biochemistry, and applications

 By Øyvind M. Andersen, Kenneth R. Markham

Flavonoids in health and disease

 By Catherine Rice-Evans, Lester Packer

The journal of neuroscience - http://www.jneurosci.org/content/25/38/8807.full.pdf

Department of Environmental and Molecular Toxicology Oregon State University - http://lpi.oregonstate.edu/f-w00/flavonoid.html

Neurobiology of Aging 24 (2003) 415–420 - http://www.chem.uky.edu/research/Butterfield/dab_pdfs/dab_pdfs/Drake%20et%20al%202003%20Neurobiology%20of%20Aging%2024%20415-420.pdf

Neurobiology of Aging 20 (1999) 325–330 - http://as-houston.ad.uky.edu/archive/as17/as17.as.uky.edu/ACADEMICS/departments_programs/Chemistry/Chemistry/FACULTYRESEARCH/Faculty/DAllanButterfield/Documents/Yatin%20et%20al%201999%20Neurobiol%20Aging%2020%20325-330.pdf

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2780015/?tool=pmcentrez

http://www.sciencedaily.com/releases/2008/06/080624110952.htm

The Beginning...

Hello! My name is Alexander Zargaran and I am currently a sixth form student at Westminster School. This is my medical blog, which I shall use as a mechanism to discuss things which I find interesting in the scientific world and medicine and I will use it as a way to get my ideas down onto e-paper. 

I shall endeavour to post monthly articles in the form of either book reviews, short articles about new breakthroughs or essays on subjects which I have researched thoroughly.
Many thanks and I hope you enjoy all the content that is to come! :)