Thursday 6 December 2012

Chemical key to cell division


In each of our cells, most of the genetic material is packaged safely within the nucleus, which is protected by a double membrane. The biochemistry behind how this membrane transforms when cells divide has finally been unravelled, offering insights that could provide new ways of fighting cancer and some rare genetic disorders.

During cell division, the membrane that surrounds the nucleus breaks down and reforms in the two daughter cells. Researchers have been split on the precise mechanisms that govern membrane reformation. One view is that proteins alone control the membrane's transformations. Another possibility is that changes in lipids – a vast group of fat-related compounds – are responsible.

Experiments had failed to show which of these two ideas was right, because it was difficult to alter lipid levels in specific compartments of cells without affecting other cellular processes.

Banafshe Larijani at Cancer Research UK's London Research Institute and her colleagues have now overcome that hurdle. They came up with a technique that transforms a type of lipid called a diacylglycerol (DAG) into another lipid, within the nuclear membrane.

Chemical cascade

The technique involves inserting two fragments of DNA into the nucleus of a cell. This causes the cell to make two proteins: the first attaches itself to the nuclear membrane, the second floats around the cell. Adding a drug – rapalogue – to the mix causes the second protein to stick to the first, which in turn causes a chemical cascade that transforms the DAG into a different kind of lipid.

Crucially, they targeted a form of DAG that does not bind to proteins, so converting it into a different lipid does not affect any processes involving proteins in the cell.

The team tested the effect of this lipid manipulation on cell division in monkey and human cancer cells. The lower the level of DAG present in the nuclear membrane, the greater the membrane malformation and chance of cell death.

This demonstrates that lipids play a role in nuclear membrane reformation that does not depend on proteins.

Larijani says it "opens the door to finding ways to kill cancerous cells" by focusing on lipids that are important to the nuclear membrane's development.

Sausage pieces

As the nucleus divides, sausage-shaped fragments of its membrane float around the cell. The fragments have curved ends, and Larijani says that changes in lipid composition generate these curves, without which the fragments cannot reassemble correctly into new membranes.

More than a dozen rare genetic conditions such as Hutchinson-Gilford progeria syndrome, which is characterised by premature ageing in children, have been linked to irregularities in cell division. A better understanding of the way the nuclear membrane forms when cells divide could be key to treating these disorders.

The research also offers a new focus for preventing the irregular cell division that underlies many cancers.

"As a result of this work we now know with confidence that DAG plays a structural role in membrane dynamics," says Vytas Bankaitis, at the Texas A&M Health Science Center in College Station, who was not involved in the study. "If we could find a molecule with suitable characteristics, this manipulation could be done [in humans], which is something that has not really been considered before."
 

 

Friday 30 November 2012

Tuesday 21 August 2012

POISON, the misconception


The first thought that comes to mind when we think of poison is the venom produced by some of the world’s deadliest creatures like scorpions, Indian Cobras, the toxic byproduct produced by chemical plants, and suspicious liquid droplets added to drinks by some bad hats in movies. Now, there is a misconception regarding poison in our society, in fact poison is ANY substance that can kill and harm an organism and ALL substances are considered as poison when it is consumed in excess doses or injected in a part of the body where it creates a negative effect. Here’s a good example, water. Drinking a hundred glasses of water in an hour can lead to one’s death due to the rapid and massive bursting of red blood cells caused by the sudden fluctuations of water potential in blood, so in this case, water is a poison. Therefore, things as common and as vital as water can be potential poisons if consumed in excess amounts. Botox, if injected in excess amounts and in locations near the heart can lead to heart failure due to its paralyzing effect on the heart’s muscles and in most cases, instant death is resulted, however if injected in an appropriate amount in places near the eyes, what it does is paralyze the muscles around our eyes which eventually reduces our wrinkles when making any facial gestures. In reality, there is no way to absolutely categorize a substance as poison because it depends very much on the doses and the location where the substance is applied, and every substance is a potential poison when applied in excess amounts.

kuanzian leong

Tuesday 7 August 2012

Exploring the impacts of chemistry on society


  Chemistry is an integral part of our lives and surroundings, the knowledge and application of it has contributed in shaping our society and civilization. In this article, the approach is to investigate the effects or impacts of knowledge in the field of chemistry on various aspects of the society.
   
  One of the most significant changes contributed by the understanding of long-terms effect created by the inappropriate disposal of domestic chemical wastes is the shift of chemical production lines predominantly by modifying the conventional process to produce a more environmental-friendly product. Based on the traditional scope of chemical’s life process constructed by Chemistry Department of UMICH, the life of chemical is broken down into three segments, raw chemical acquisition, production and processing, and product utilization. The fate of product (in this case, chemical) after its disposal was not normally taken into consideration by manufacturer. Such ignorance has certainly created complex problems with large scale impact on the environment and ecosystem while providing simple solutions to satisfy immediate societal demands. Take the case of plastic for example, while enhancing the packaging of industry; the disposal of this chemical product has resulted in many environmental problems threatening the society. In Plastic Waste Management Awareness Creation and Public Education program launched by Ministry of Environment Science and Technology (MEST), the ministry declared an astounding statistic that seventy percent of plastic disposed in Ghana ended up in drainage system and other open spaces, and since plastic is non-biodegradable, it forms permanent clog in the sealed underground drain, which is a major cause for flooding. Also, the lack of effort in treating plastic waste is demonstrated when Environmental Protection Agency (EPA) announced that only seven percent of plastic waste in the world is recycled. After studying the long terms effect created by domestic chemicals and taking considerations on the impact of these products on multiple aspects especially environment and resources scarcity, the ideas of “treatment disposal” and “retirement and recovery” are incorporated into the products life cycle and subsequently causing a shift in production lines of various products particularly the domestic chemicals. This is to mitigate the negative environment impact of chemicals after its disposal. Back to the case of plastic, in the past twenty to thirty years, plastic-making industry has diverted its conventional productions line for plastic. One of the most common examples is to insert carbohydrate or sugar molecule in plastic to make its products more bio-degradable etc. in order to reduce its environmental impacts. Problem such as clogging of underground piping system caused by the improper disposal of plastic waste can be then significantly reduced for these new plastics can be decomposed more easily and thus would not result in the formation of permanent clogs. The case-study regarding plastic is just one of the many examples of how the knowledge on effects of chemicals have contributed in modifying the production lines of domestic chemicals from manufacturing perspective, and with the growing understanding and studies regarding the long-term effect of domestic chemicals, there will be even more modification and diversion in the process of synthesizing domestic chemicals in the future.
  
  The widespread knowledge regarding chemicals and its impact changes not only the industry but also the consumers’ preference over the choices of domestic chemicals. Chemicals’ database sharing network like PublisherChem, ChemSpider, and even the FDA agency have provided a tremendous amount of information regarding the effects, usages etc. of many domestic chemicals online. With the growing competition in food industries, addition of preservatives, coloring, flavoring to the food products has become a preference for most of the manufacturer in order to improve the taste, appearance and prolong the expiry date of their products. In recent years, there are discoveries that show certain unpleasant side effect caused by food additives. Tartrazine (Sunset Yellow E110) for example, has proven to be one of the factors that cause hyperactivity in children, and sodium benzoate (E211) is known to be a potential carcinogenic compound after reacting with other chemicals found in human body, after the discovery, Coca-Cola announced that it would be phasing out sodium benzoate from many of its drinks in year 2008. Also in Malaysia, acts such as 1983 Food Act, 1985 Food Regulation are signed to control the quantity of additives permitted in food. With the development of chemical database sharing network, food act etc. over the decades, it is not uncommon to see a general public preference shift from food with flamboyant color, heavy taste to food with natural flavoring, and quote like “stop adding E numbers to my food” begin to emerge in the community. Everyone is going for a better or arguably more natural type of food. Unfortunately, the shift of preference is only true in the relative affluent and middle-income society, for they have a wider range of choices over the food, and the people who live in poverty will still continue to consume food with high concentration of these unhealthy artificial food additives because the latter can be synthesized relatively easily by laboratory in large quantity, thus it can be sold at low price.
  
  Buildings have become more than just a compartment for people to stay, but a landmark that represents the culture of a particular place. Advancement in material chemistry particularly in the research and synthesis of polymers has given rise to many buildings with intricate architecture. Such novel material has been found to have many advantages over its conventional alternatives such as concrete (the nightmare of architecture) and glass. Concrete is tough and able to withstand high tension, but it is incapable of building complex structure, glass makes building looks elegant but its advantage is simply outweighed by its fragility and large mass. Polymer is, however, able to withstand high tension, light and can be molded into different shapes. In recent years, polymer such as ethylene tetrafluoroethylene (ETFE) has become the crème de la crème of various well-known engineering firms like ARUP. ETFE is used by ARUP to build many notable buildings across the globe such as Beijing National Aquatic Center or affectionaly known to be the water cube, Allianz Arena in Munich, Germany etc. The rapid progress in the development of material chemistry is changing many conventional thoughts on how a building should look like, and gives rise to the emergence of novel architecture, design and most importantly, it provides a new way for people to express their culture and heritage.
   
  Chemistry in many ways is changing our society, it is a part of our lives that we constantly take for granted, and this ignorance has caused chemicals to be particularly vulnerable to the misusage by irresponsible parties. We should at least from now, be sensitive to the domestic chemicals around us, make efforts to understand the labels on chemical products, and play our part to ensure that knowledge of chemistry is only used for the benefits of mankind and the environment in synchrony with the marketing slogan used by DuPont Chemical Company, “better things for better livings…through chemistry”. 

kuanzian leong

Monday 26 December 2011

Why do people need to know about chemistry?

Chemicals form an integral part of our daily life, ranging from detergents, additives we consume, and the pharmaceutical drugs we take. Unconsciousness towards facts regarding chemicals disallows us from utilizing the chemicals around us to its uttermost potential. The misusage, abuse and unaware of the danger of chemicals may even bring about harm to oneself, society and environment.