Hydrolysis of Phosphomonoesters Study

Hydrolysis of Phosphomonoesters Study Introduction Site-directed mutagenesis was the primary basis of this portion of the laboratory directed toward determining the active site of the enzyme catalysis for hydrolysis of phosphomonoesters. The criteria was to turn the original sequence with Arginine 166 into Glutamine 166 through a point mutation. The primer location is located in the 401511 sequence of the phoA gene of alkaline phosphatase in E. Coli. The primer sequence is: 5- G CTG GTG GCA CAT GTG ACC TCG CGC AAA TGC TAC GGT CCG AGC -3’. The mutated primer sequence is: R166Q1 5’-G CTG GTG GCA CAT GTG ACC TCG CAG AAA TGC TAC GGT CCG AGC-3’. The reverse complementary mutated primer sequence is: R166Q2 5’-GCT CGG ACT CGG ACT GTC GCA TTT CTG CGA GGT CAC ATG TGC CAC CAG C-3’. A calculation for the melting temperature can be determined by the following equation: TM= 81.5 + 0.41 (%GC) – 675/N- % mismatch The TM value for Gln-166 was determined to be 85.95ËÅ ¡C. It is necessary for the TM value to be above 75ËÅ ¡C for successful mutation. Running on the null hypothesis, it would be clear that nothing would change for the kinetic parameters. If something were to change, the kinetic parameters for the Michaelis constant (Km), which determine the velocity of an enzyme as well as calculated to be  ½ the Vmax, would be hypothesized much higher after the mutation to glutamine since the mutation allows for 61% more accuracy from arginine’s CGG at 25% to glutamine’s CAG at 86%. The increase in the binding affinity creates the hypothesis that since it is bound closer together creating a stronger binding affinity, the maximal speed (Vmax) would be reduced since it does not require as much conversion between substrate and product. Mechanism of Alkaline Phosphatase Alkaline phosphatase (APase) is an enzyme located in the periplasmic space of E. Coli. The structure of APase, usually in the form of a dimer, shows two zinc metallonzymes and a magnesium ion in the active center. There is a bridging ligand with the protein Asp51 in the active center for the two zinc ions and the one magnesium ion. There are four phosphate oxygens; two phosphate oxygens form a phosphate bridge between the two zinc ions and the other two form hydrogen bonds with the guanidinium group of arg-166 (Coleman, 1992). The dimer is two identical subunits that each contain 429 amino acids. (Coleman, 1992). The most important amino acids located at the active site of APase are the four Cysteine residues represented as combined intrachain disulfides. The phosphorylated residue was Ser 102, which is phosphorylated during phosphate hydrolysis, to begin the nucleophilic attack on phosphorus. Each monomer contains a leucine rich environment of 22 residues. (Coleman, 1992). The first zinc ion is necessary in activating the leaving group of the ester oxygen in order for Ser 102 to phosphorylate (Coleman, 1992). The second zinc ion is necessary for the ester oxygen of the serylphosphate to begin activation of the phosphoseryl intermediate during hydrolysis of Ser 102. When the phosphoseryl intermediate is formed during the first zinc formation, a hydroxide is formed. (Coleman, 1992). Figure 1: this figure represents the monomer of alkaline phosphatase showing the zinc triad with magnesium in the active center. (Coleman, 1992). The proposed mutation as discussed, is mutating the arg-166 to glu-166. It is speculated that there will be no effect on the enzyme during the mutation. Arg-166 is located in the guanidinium group and is an electrophilic species while APase is being phosphorylated. Arg-166 is speculated to play a role in stabilizing the developing negative charge on the oxygen of the leaving group, pentacoordinate transition state, or help bind the phosphate group. As discovered byButler-Ransohoff et al, it is discovered that Arg-166 has no effect on the hydrolysis of phosphate monoesters and therefore will not be effected after mutation. Competent Cells Competent cells are used to help the DNA get into the cell. DNA is negatively charged and the calcium ions from the competent cells of DH5-ÃŽ ± cells are positively charged. The purpose of calcium chloride’s positive ions is to create an equilibrium between negative charge on the cell membranes phospholipid heads and the phosphate group on the plasmid DNA. This is where the genetic modification occurs. Therefore, they help by binding to the DNA and move it into the cell after the cell goes through a heat shock cycle. Competent cells have a very high rate for transformation efficiency. The proposed understanding of how this works, is that the calcium ions are positive and therefore weaken the electrostatic repulsion, which in turn weakens the cell walls. When the cell goes through heat shock, it causes the pressure to increase opening the cell and allowing the competent cells to bring the DNA into the cell by allowing pores to be created with the weakened cell wall. This forces the plasmid to become supercoiled so that it can pass through the pores created by the charge difference and heat shock. The competence comes from the cold bath of DH5-ÃŽ ± cells in calcium chloride which shocks the cells causing pores and then heat the cell to 42ËÅ ¡C for roughly 2 minutes, more than this could cause the cell membrane to denature and the pEK-154 mutated plasmid would become denatured. DH5-ÃŽ ± is a strain from E. Coli commonly used in laboratory practices due to it having the phoA- gene deficiency. This is necessary and desirable because it is easily transformed for creating competent cells. DH5-ÃŽ ± cells are used because they are a common strain in E. Coli and are commonly used for cloning. In addition, they promote stability and help improve the quality of the plasmid when using the Miniprep kit. (Dagert, 1979). A growth curve was created after incubation of the cells for competent cells. This was done to show the growth period during the lag phase is depicted by the highest point on the growth curve. This is taken to determine how much growth you have and is determined through a logarithm vs. time on a graph. The method used is optical density (OD) at 600nm to measure the transmittance on a spectrophotometer. If the value for the OD600 is high, the protection factor by a filter is lower and vise versa. This method is used to determine how much light is absorbed through the bacterial cells. Site-Directed Mutagenesis The sequence chosen for the point mutation from Arginine 166 to Glutamine 166 was sequenced in Ann Arbor. Site-Directed Mutagenesis synthesizes two complimentary oligonucleotides double stranded DNA template with glutamine 166 mutation, which is tagged with unmodified nucleotide sequences to a single stranded DNA template to allow mutation to occur and then reforms the new double strand DNA template during thermal cycling. When this occurs, the newly single stranded DNA template forms complementary strands with the enzymes and nucleotides to produce a higher result of strands. The purpose of site-directed mutagenesis is to make specific changes to the DNA sequence of a gene. Quik Change Lightening Mutagenesis kit provides a faster and more reliable insertion of the mutation with a simple three step method. The multiple cycles are subjected to a polymerase chain reaction (PCR) method. This allows multiple sets of mutated DNA to be produced within a short period of time. PCR works by heating and cooling the samples, since the double DNA is subjected to separation when heated it causes the srtands to separate allowing nicks in the template to occur. pUC-18 is a control plasmid used for determining if a mutation was successful and efficient. Figure 2: pUC-18 plasmid DNA genetically mutated to contain the LacZ gene as well as the ampicillin resistance gene. The polylinker cuts the section of the DNA by the Dpn1 restriction endonuclease creating a linear DNA strand allowing for the binding of the mutation of Arg-166 to Glu-166 to occur. pUC-18 is a circular double stranded DNA molecule. The reason pUC-18 was chosen as the control positive plasmid is because it was genetically manipulated to contain an ampicillin resistance gene as well as a ÃŽ ²-galactosidase enzyme known as LacZ. The lacZ gene is essential for DNA mutation because it contains a region to insert a polylinker, which recognizes the Dpn I restriction endonucleases during digestion causing the plasmid to become linear and bind to the mutated plasmid DNA that has also been cut with the Dpn I restriction endonuclease. A pWhitescript is used as the positive control plasmid used for mutagenesis. The control plasmid is combined with pEK154 plasmid containing the phA gene of APase and the vector double stranded DNA. The two oligonucleotide primers are the opposite ends of the vector. pWhitescript has the stop codon TAA inserted that stops the ÃŽ ²-galactosidase enzyme from producing. The two oligonucleotide control primers create a point mutation that turns the T residue of the stop codon to the C residue of the glutamine codon (Gln, CAG). That allows enzyme ÃŽ ²-galactosidase to be produced after pWhitescript is subjected to mutagenesis. There are two oligonucleotide with the mutation primer as discussed earlier. New DNA polymerase called Q1 enzyme was used for double stranded DNA template when combined with dNTP mix it extended the two-oligonucleotide primers as well as allowing the new plasmid DNA to construct. PCR Cycling parameters were used during Quik Change Site-Directed Mutagenesis for the transformation of arginine to glutamine by the use of the Pfu Enzyme. As visible from table 1, the cycling parameters were set up for this specific reaction for a point mutation. After cycling, the non-mutated parental supercoiled double stranded (dsDNA) is digested. Table 1: Quik Change Site-Directed Mutagenesis Parameters Segment Cycles Temperature Time 1 1 95C 2min 2 18 60C 60C 68C 20 sec 10 sec 30 sec/kb of plasmid length (3min) 3 1 68C 5 min The first step of the three step simple method for Quik Change Lightening Mutagenesis kit is Thermal cycling at 95ËÅ ¡C for two minutes. During this time, the DNA template becomes denatured allowing the primers to be subjected to heat treatments, which denature the pEK-154 template DNA strand and synthesizes the primers to extend linearly and cause nicks with Pfu Fusion-based DNA polymerase, which are then sealed by components within the Pfu enzyme blend. This polymerase allows for exact replication of original template and does not disrupt the orientation. The original mutated pEK-154 was used as the supercoiled double stranded DNA template Figure 1: during thermal cycling, the double-stranded DNA Template is nicked and subjected to point mutation for arginine 166 to glutamine 166 and then sealed with components in the Pfu enzyme blend. In the second step of the kit the template digests the parental DNA strand with methylated and hemimethylated DNA using the enzyme Dpn I endonuclease and subjected to thermal cycling for the second segment. The un-mutated pEK-154 plasmid DNA is the parental DNA while the mutated pEK-154 is the plasmid DNA with the desired mutation. With the nicks, the mutated plasmid with the two oligonucleotide primers is mixed with Dpn I endonuclease for methylated DNA that targets the sequence 5’-Gm6ATC-3’. This sequence helps digest the pEK-154 parental DNA template and has not been introduced into the methylase enyme allowing methylation to not effect the DNA and therefore will not be digested with the parental DNA strand. Similarly, the un-mutated is also digested in Dpn I restriction endonuclease to be methylated. Figure 2: Dpn 1 enzyme endonuclease digests the parental DNA template with methylated and hemimethylated allowing for single stranded DNA for transformation. Step 3 is the last cycling step where transformation of the newly mutated glutamine 166 single-stranded DNA. The DNA is added to Dpn I restriction endonuclease, which forms it into linear DNA stranded DNA duplex forming a double stranded DNA for the newly synthesized mutated DNA. After the mutated vector DNA with the primers has been nicked it is transformed into CaCl2 competent DH5-ÃŽ ± cells. This transformation must occur to repair the nicks caused during cycles to separate the DNA strands. The pWs, which is used as the control DNA is also transformed with competent DH5-ÃŽ ± cells to help repair the nicks. Transformation Control screening used X-gal and IPTG to determine if ÃŽ ²-galactosidase activity. The newly mutated pEK-154 cells are screened for alkaline phosphatase activity. This helps screen for ÃŽ ²-galatosidase enzyme in E. Coli is a Lac Z gene that codes for this enzyme. This enzyme is useful because it breaks the lactose into galactose and glucose. A Lac operon contains an operator and a promoter, which binds RNA-polymerase that starts transcription for the Lac I gene for I protein which can only bind to operator or lactose, but not both. When I protein is bound to lactose, in this case Isopropyl-1-ÃŽ ²-D-galactopyranoside (IPTG) which mimics the structure of lactoase allowing RNA-polymerase to bind to the promoter to produce ÃŽ ²-galactosidase. 5-bromo-4-chloro-3-indolyl-ÃŽ ²-D-galactopyranoside (X-gal), which is a substrate that cleaves galactose in ÃŽ ²-galactosidase to produce a blue color. If no ÃŽ ²-galactosidase is present they turn white on the agar plates. This determines if the cells contain the mutated CAA codon for glutamine instead of the stop codon TAA of the unmutated protein. 5-bromo-4-chloro-3-indolylphosphate (BCIP) is used to determine if alkaline phosphatase is present. BCIP like X-gal is a substrate that cleaves the phosphate group off of alkaline phosphatase producing a blue color.

Green Laws Boost Clean-up Industry :: essays research papers

Green Laws Boost Clean-up Iindustry Engelskaflevering d. 01.09.95 I Have companies around the globe really become "house-proud", or is planet earth just in for a spring cleaning? It is hard to say - but one thing is for sure; the environmental sector is en-joying a boom. The market for pollution control technology is on a steep exponential growth curve, which seems to be interminable. Especially the European companies put down their names for an immense part of the expansion. But what is the precise nature of this sudden environmental con-cern? After all the deteriorating state of the environment is hardly a novel phenomenon, to say the least. Just how vigorous this potential goldmine is going to be for the clean- up industry ac-tually depends on law and order, so to speak. That is to say that one of the main reasons for the turn up is new legislation. Recent EU-directives as to pollution may cause heavy demands on the purse of one company and consequently pour that money down the pockets of the clean technology indu-stry. Moreover the deadlines for plants to meet EU-directives are getting close, and everything se-ems to show that the laws will be enforced. Yet far from all companies have to meet with the raised finger of the law to start investing in their environmental responsibilities. Investments on a volunta-ry basis are often due to the fact that it makes good ecnomic sense or because it gives the corporate image a face- lifting. Seen from a geoprahical point of view Germany and primarily eastern Europe form tremendously good breeding ground for the sale of clean-up equipment. As a result of opencast mi-ning of lignite coal in Poland, for example, a huge clean-up is left, which will amount to billions of dollars. However accidents also occur at sea, where a spate of oil tanker disasters are likely to fill out the order book at oil cleaning industries. Nevertheless a stroke of bad luck is far from necessary in order to make firms under-stand their green obligations. The power of the consumers has been on the increase over the last few years, and the public environmental image means more to a firm than ever before. The average con-sumer going down to the grocer's for a few necessaries is starting to attach importance to something else than just the product itself. How is the detergent wrapped - is the paper bleached? Is this bottle reusable? Are these outdoor tomatoes? - and so on. Personally I don't think that you notice it, as you're walking alongside the shelves in the local supermarket - but you do pay

Cyberspace and Internet Censorship Essay -- Argumentative Persuasive E

Cyberspace and Internet Censorship "Governments of the Industrial World, you weary giants of flesh and steel, I come from Cyberspace [the Internet], the new home of Mind. On behalf of the future, I ask you of the past to leave us alone. You are not welcome among us. You have no sovereignty where we gather" (Barlow 18). The Internet is a vast network of computers, both public and private, which spans the globe. Recently, there has been a movement by governments worldwide, and the United States government in particular, to remove content deemed inappropriate from the Internet. However, numerous factors such as: the abundance of less restrictive alternatives, the impossibility of applying American law and community standards to an international communications medium, the active choice required to access the Internet's resources, the violation of our constitutional rights which it entails, and the fact that it is the parent's and not the government's responsibility to protect children contradict this rash and poorly thought out idea. While censorship is intolerable in all its forms, it is especially odious, inappropriate, and unworkable when applied to the Internet, an international medium of free speech, information, and communication. The Internet began as a link between major universities and government computer centers to facilitate the sharing of information and allow certain universities to utilize the few existing supercomputing centers. With the advent and popularization of the personal computer and the increased use and development of modems, the size and capabilities of the Internet have exploded. The nature of the Internet is such that it is very difficult, if not impossible, to determine its size at a given mo... ...because they may inadvertently happen upon objectionable material. The resources of the Internet deserve the same treatment. Censorship is unnecessary and inappropriate with regards to the Internet. Numerous less-restrictive means of protecting the public, the global nature of the Internet, the active choice required to access the resources of the Internet, the fact that Internet censorship violates the First amendment, and the parental and personal nature of regulating the Internet all contradict the idea of Internet censorship. The Internet has the potential to revolutionize our society and bring us full into the information age. The information superhighway is not centuries or decades away, but just around the corner. Let us attempt to aid the growth of this technology and its respective culture in any way possible, and thus propel ourselves into the future.

The Accounting Cycle

In the general point of view, an accounting cycle refers to certain procedures that must be established by every business unit to provide the data to be reported on the financial statements. The accounting process consists of two interrelated parts: the recording phase and the summarizing phase. Although these phases vary in details depending on the nature of the business, the main purpose is just the same – to be able to provide an accurate report containing the firm's condition and the result of its operation. To clearly illustrate the complete accounting cycle of a finance company, let us take as an example Dann & Berns, Inc. The company is engaged in providing business analysis including credit investigation, a thorough study of the company profile, review of the client's financial statements, and providing an overall rating of the clients, whom we will call as subjects in this example. Among Dann & Berns' subjects include big companies who are applying for accreditation as a distributor of another firm; applicant verification for banks and other financial institutions offering various types of loans, as part of their pre-approval requirements; outsourcing companies and other headhunting firms for hire-right purposes; and others from different industries. To be able to provide the necessary services, Dann & Berns is hiring very senior financial professionals for these functions. These professionals are required to have a solid background in finance and accounting as well as the ability to communicate with the top management of different financial institutions. A deep knowledge on financial analysis is highly expected from them. The Operations Department is involved in the main process and is consist of report coordinators, field officers, business analysts, and editors, who are all directly reporting to the vice president. Other departments providing support include marketing, human resources, legal, information technology, accounting and audit. The marketing people are the ones who have direct contact with the subject. They collect and forward the primary documents and other requirements to the operations department through the report coordinators. The report coordinators will then input necessary data for monitoring and assignment of subjects to the business analysts. The editors are responsible in reviewing the work of the business analysts. Their responsibilities include double-checking of the ratings given to the subject, based on their company profile, the result of background checks, outcome of credit investigations made, and the content of their financial statements. Field officers are the ones who do the personal background-checking and other liaison work including but not limited to gathering of pertinent documents from the Securities and Exchange Commission, IRS, Federal Bank and other banks, and other regulatory bodies to authenticate the validity of the papers submitted by the subject. Once the accreditation process is done, the editors will forward the reports back to the report coordinators, who will then issue a list of completed reports per subject to the accounting department for billing purposes. This is the starting point of Dann & Berns' accounting cycle.

General Information and Cure for Alzheimer’s Disease

This research paper in general provides various details about the Alzheimer’s disease. The various symptoms and the various methods used to detect this disease. It also provides in general information about the methods that are used to cure the disease. Some of the natural techniques used to cure it. The various social and physiological issue faced by people suffering from this disease. Introduction Alzheimer's disease is an irreversible brain disorder which has no cure.This disease affects its victims slowly over a period of time and leaves them with no or very little control of their mind. Some of the affects of Alzheimer's disease are partial or total memory loss, they are not in control of their mind to make judgments, it leads to personality changes in the affected person and many a times they loose their control over their language skills. Alzheimer’s disease is one of the disease that affect its patients over a long span of time and with out a warning.The symptom s of Alzheimer’s disease are very similar to that of old age and are many times misinterpreted as old age and by the time people realize the actual problem it is too late. Some of the most common and early signs of Alzheimer’s disease is the loss of short term memory and this is one of the ignored by many and slowly and steadily becomes worse over a period of time. There are a number of organizations that have been started to find a cure for the disease and also to help the victims cope with the stigma faced by them in the general public.One of the major organizations started to help this cause is the Alzheimer's Disease Research (ADR) which was established way back in 1985 to provide funds to organizations performing research on Alzheimer's disease and also to educate the general public about the disease and raise awareness about the same. Alzheimer’s disease Alzheimer's disease was first detected by a German physiotherapist way back in 1901 when a patient was brought to him by her husband as he was not able to take care of her due to her ever diminishing mental health.He noticed that the patient was suffering from short term memory loss and cloud not remember a thing. He continued research on these symptoms for the next 5 years and presented the same at the 37th Assembly of Southwest German Psychiatrists. The name Alzheimer's disease became popular after it was written about by Emil Kraepelin in his book called â€Å"Textbook for Students and Doctors†. However in the whole 20th century this disease was assumed to affect only the people who were of age 60 and above.However in early 1980s it was realized that this disease could affect anyone in any age group and the name Alzheimer's disease was used to refer to all the patients who were contacted with this disease (Alzheimer’s Research Foundation). Alzheimer's disease stops the normal functioning of the brains and reduces its capabilities to perform normal everyday activities . The disease grows over a span of time and the affected persons control over his brain lessens as time passes. Alzheimer's disease is an irreversible disease which has no found cure.The person who is contacted with this has no or very little control his brain and is not able to think and understand things correctly. The patient many have short term memory loss and may forget his name and many a times it has been noted that the patient will walk away from home and wander around not knowing what is to be done. The first sign of Alzheimer's disease is the loss of short term memory. This is a sign which is ignored by many as a sign of old age and by the time one realizes the issue it is too late.Over a span of time the person looses his thinking abilities and finally it leads to a change in the personality of the person suffering from Alzheimer's disease. In the last stage the person become fully dependent on others for his day to day activity and has to be kept under supervision at al l times. The person may get infected by an infection which may eventually lead to his death. It is said that usually people over the age of 65 are contracted with this disease however one can come in contact with Alzheimer's disease at any age.However age is the key factor for people who suffer from this disease as it ahs been noted that the chances of a person having this disease increase as the person grows older (Wikipedia). Some of the common symptoms of Alzheimer's disease are as follows; Short term Memory loss (Cohen): There are a number of symptoms that will be noticed in a person who is suffering Alzheimer's disease, however the most common and one of the symptoms that can be noticed in all the patients is the loss of short term memory.All the patients suffering from Alzheimer's disease loose there short term memory and are known to become forgetful. Short term memory loss is considered to be one of the key symptoms of Alzheimer's disease. However many time patients avoid te lling this fact to people around them and are know to smartly hide this issue. This is done by them to avoid being made fun by their family members and friends. Confusion and Wandering: Memory loss is followed by problems related to confusion where the affected person finds it difficult to perform even their everyday work properly.They find it difficult to perform some easy everyday work like cooking, eating etc very difficult to do. It becomes very difficlut for them to remember the name of people and places. It worsens to such an extent that they forget the names of their own children and grandchildren. This further worsens and the patient looses track of direction and finds it difficult to find his way around the house and many a times once he goes away from the house, does not know the way back home and is then referred to as a wanderer.In the beinging the affected person will not realize the problem and as time passes things will worsen and the person will find it very difficul t to find his way back home. Personal Care: The personal hygiene of the person suffering from Alzheimer's disease will deteriorate over the span of time. A person who would really take care of his hygiene will start ignoring it. The person will not want to have bath or brush his hair everyday, will forget to brush their teeth etc.Many times the person will start having a weird sense of dressing and will start wearing inappropriate dressing. In this stage a personal care taker will be needed to take care of the everyday work of the person and the patient will require constant help in doing their everyday activities. Mood Swings: A patient suffering from Alzheimer's disease will have massive mood swings and the person will behave differently on a day to day basis. There will also be sudden and quick changes in the person; they might start laughing when they would have been crying only a minute back.They might even start having fights and arguments with themselves or a non living objec t like the floor or even the television. They will start fighting with anyone around and will always be restless. They might even start talking to themselves and mumbling. Sundowner Syndrome: During the stage when the person starts having mood swings, he also starts suffering from the Sundowner Syndrome where the sunset has a very bad affect on the patients brain and the person becomes every restless and becomes over active during the night and early morning hours (Richter & Richter).Diagnosis (Alzheimer's Disease): The diagnosis of a person Alzheimer's Disease is a long and lengthy process and is based on the observations made by the physician over a period of time. A series of tests to check the memory of the person are done over a period of weeks or months to asses the condition. The physician performs number of other tests too to rule out any other disease that the person might be facing. This is done only to check for the symptoms of other diseases, as no clinical test has been proven to diagnose Alzheimer's Disease completely.All the diagnosis is based on the experience and knowledge of a physician who specializes in memory related disorders. The only guaranteed way to detect the Alzheimer's Disease is to do a micro scopic examination of the tissues of the brain. Causes of Alzheimer's Disease (Cohen): There are a number for theories have been formed about the causes that lead to Alzheimer's Disease, many of these have been accepted universally and on some of the other theories research is still on.Some of the causes of Alzheimer's disease are as follow (Richter & Richter)s: Bacterial Infection: Bacterial infection is considered to be one of the major causes of Alzheimer's Disease. Chlamydia Pneumoniae is a virus that usually affect the lungs, nose and sinusus of the infected, however it has been noted that this virus is very prominentnt in the brains of people suffering from Alzheimer's Disease. In a research doen recently seventeen out of ninteen patien ts suffering from Alzheimer's Disease had the virus in their brains.Brain Damage or Head Injury: The chances of a person having Alzheimer's Disease become very high after a person has an head injury. The trauma that the brain has when a person has a head injury leaves traces of amyloid which is know to cause Alzheimer's Disease. Age Factor: Another major factor that increases the risk of Alzheimer's disease is the age of the person. It is said that the chances of Alzheimer's disease occurring increases after the age of 65 and every 5 years after that the risk increases by about 5 percent.Genetic Cause: It has not been scientifically proven that Alzheimer's Disease is a genetic disorder and people who have family memebers suffering from the diesease have a high risk of having the disease. However it has also been proven that genetic factors only increase the risk of Alzheimer's disease. Environmental Causes: There is also an argument about how high levels of aluminum in the environme nt increases the risk of Alzheimer's disease, however there is not scientific proof of this actually being a cause.Some of the steps to be taken to reduce the risk of Alzheimer's disease are as follows; Intellectual Stimulation: One of good ways to reduce the risks of Alzheimer's disease is by doing metal exercise and doing things that requires one to work their brain. This helps in keeping the brain healthy and in good shape. Regular exercise: Another good way to reduce the risk of Alzheimer's disease is by doing regular physical exercise. This helps reduces the amount of cholesterol in the body and also reduces the fat. This reduces the risk of Alzheimer's disease.Healthy Diet: The risk of Alzheimer's disease can be reduced by having food that is rich in vitamins and proteins. Also reducing the intake of fat also helps in reducing the risk of Alzheimer's disease. Lowering Cholesterol Levels: Reducing the levels of cholesterol in the blood also helps in reducing the chances of a pe rson having the disease. Many clinical trails are also on to check the risk factor. There is another study that has found that compounds found in marijuana known as cannabinoids helps in preventing Alzheimer's disease.However they have not been able to prove it for a fact or replicate the same. Some of the important facts about Alzheimer's disease are as follows (Alzheimer’s Research Foundation); 1. Over a 100 billion dollars are spent a year to do research and to find a cure for the disease. 2. Around 24 million people around the world suffer from Alzheimer's disease. 3. Around 5 million Americans are suffering from Alzheimer's disease. 4. It is estimated that over 81 million people around the world will be suffering from Alzheimer's disease by 2020.Conclusion It can be clearly understood the gravity of the disease and the problems faced by a person suffering from the disease. It is very important for a person to lead a healthy life and be careful if they have Alzheimer's di sease in their family as there are chances that they may have the disease themselves. It is also necessary that one does not ignore the symptoms of short term memory loss as this can be the beginning of the disease and if found at the right stage it is possible to slow down the process of it damaging your brain.Research is on to find out a cure for the disease and reduce the risks the disease. References Alzheimer’s Research Foundation. (n. d. ). Retrieved from http://www. alzinfo. org/alzheimers-disease-information. asp? mtc=google&kwd=alzheimer's_disease&gclid=CIuZgcqL34sCFQIFEAodcyncXg Alzheimer's Disease. (n. d. ). Retrieved from Wikipedia: http://en. wikipedia. org/wiki/Alzheimer's_disease#History Cohen, E. Alzheimer's Disease. Richter, W. R. , & Richter, B. Z. Alzheimer's Disease.

Biological Oxygen Transport Essay Example | Topics and Well Written Essays - 1500 words - 1

Biological Oxygen Transport - Essay Example The chemical reactions thus require enzymes to speed up their reaction. Most of the enzymes require metallic entities to help them function to their full capacity. Metallic ions like Zinc and Magnesium provide biological enzymes with good acid capability. Thus, the enzymes that are used for acid base reactions use magnesium and zinc at their active centers. In addition, inorganic compounds like sodium and potassium are required by living organism to create a potential difference across cell membrane. Unequal distribution of sodium and potassium ions across cell membrane help initiate an action potential. Hemoglobin is an iron containing oxygen transport metalloprotein that is found in the red blood cells of vertebras (Anthea, Human Biology And Health). Its structure exhibits characteristics of both quaternary and tertiary structures of protein (Kessel, 122 Print). Most amino acids present in the hemoglobin are alpha helices and are joined together by non-helical structures. Hydrogen bonds present in the helical structure stabilize the helical units and give hemoglobin molecule its specific shape (Hemoglobin Tutorial, University of Massachusetts Amherst) The hemoglobin molecule has a protein part globin to which a small iron containing group heme. The heme consists of a charged iron ion that is contained in a heterocyclic ring. This heterocyclic ring is known as porphyrin and it consists of four pyrrole molecules linked together with iron bound in the center (Hemoglobin-School of Chemistry, Bristol University, ). The iron ion is the oxygen-binding site of hemoglobin. The iron ion coo rdinates with four molecules of nitrogen. The iron ion is strongly bound to the protein via imidazole ring of the F8 histidine residue below porphyrin ring. A sixth position bind oxygen reversibly by coordinate bond to complete the octahedral group of six ligands (Wiki Premed,

In what ways do colonialist ideas continue to influence contemporary Essay - 1

In what ways do colonialist ideas continue to influence contemporary culture Describe with reference to fashion, literature, fi - Essay Example In the modern world, both colonialism and imperialism are practiced indirectly in various nations across the world. Nations with political and economic superiority across the world, such as the US and other European nations, exercise direct and indirect global control. The dominant powerful nations are using grounds, such as art, film, literature, and fashion to ensure a constant global expansion of their dominance. Often, imperialism is justified as a means of bringing people the blessings of a superior and modern way of life or of liberating them from tyrannical rule. The act results from a variety of causes including economic pressures, greed, human aggressiveness, search for security, prestige, search for power, humanitarianism, national emotions and many other factors. These motivating factors make it difficult to eradicate imperialism. However, they are also very beneficial especially for nations susceptible to victimization because they make it easy for them to suspect policie s that might turn out to be imperialistic (Sartre, 2001). For example, some states in the Third World have accused former colonial masters and other powerful nations of neocolonialism. The post-colonial theory clearly explains the modern spread of colonial ideas in various forms. Post-colonial theory involves the study of interactions between colonialist nations and the societies that they colonized (Gandhi, 1988). The theory examines the effects of the domination and colonization of non-European people, land, and cultures. The key concepts in this theory include history of colonialism and representation, and identity of modern cultures and other practices (Gandhi, 1988). Majority of studies have shown that Western traditions and cultural practices especially regarding thought, music, fashion, and literature dominate the global culture. Non-Western traditions, cultural practices, and other forms of expression are widely excluded and marginalized in modern practices. This field of po st-colonial studies was greatly influenced by a Palestinian literary critic named Said. Through his popular piece of work known as Orientalism, Said sought to depict how Middle Eastern and African Arab people and their cultures were represented as the exact opposite of occidental and Western cultures (Said, 2003). Orientalism is a reflection of the Western style in restructuring, dominating, and acquiring total control over the East (Celik, 1996). In his literary piece, Said argued that the modern orient representations impose colonial dominations by implying that oriental cultural practices are inferior in relation to Western cultures. The Western culture is brought out as a culture with a rich history, with morally superior and virtuous practices. On the other hand, the oriental culture or third world practices have its history imposed on it by powerful facets with possessive and submissive practices. In addition, the oriental culture is brought out as strange, lazy, and weak and one that promotes immoral and unequal practices (Said, 2003). According to Said’s argument, the Western superior nations are making every effort possible to make the colonized people admit that their culture is inferior, unrealistic and imperfect in character (Said, 2003). The colonizers promote their history, language,