Friday, October 18, 2019
New Test Development Project Risk Monitoring and Control Assignment
New Test Development Project Risk Monitoring and Control - Assignment Example Basically, the project monitoring and evaluation in this project management are meant to provide objective and reliable up to date information about the progress of the project and as such helps eliminate unnecessary risks. Four basic indicator systems will be used in the project monitoring and control which includes; Schedule Performance Monitoring, Program Metrics, Technical Performance Measurement (TPM) and Earned Value (EV) (Kerzner, 2006). An in-depth monitoring and control of scheduled risks will be conducted to gauge the extent of the damages caused by such risks if any will be undertaken during the project implementation. After 30days, the project management staff will conduct a scheduled performance monitoring indicator to establish whether the time allowed for a risk that may occur as a result of the delay caused by the NATA in granting accreditation of the assays was within the acceptable limits. This process will be done to ensure that the overall implementation period of the project is not compromised by risks caused by NATA. The project monitoring and control tool will also be used to check the effectiveness of the rejection of the risk to proceed to offer service without NATA accreditation. The process will find out if adopting the risk would have dented the image of a project as earlier been presumed. There are other risks such as technical risks that have been identified as possible causes of delays in the implementation of this project. However, program metrics and earned value (EV) are some of the indicator approaches that will be used to monitor and control the adopted response strategies. The project has adopted risks such as the failure of assay design, challenged validation report by NATA assessor and service redundancy. Likewise, during the implementation of the project risk monitoring will be done against the above-named risks to estimate the effectiveness of the decision of adopting them.Ã
Thursday, October 17, 2019
Business International Law Essay Example | Topics and Well Written Essays - 750 words
Business International Law - Essay Example However, this fund is just made accessible after the country requiring the loan has applied certain structural adjustment program (www.imf.org). Structural Adjustment Programs (also known as SAPs) are economic policies created by each country but having shared common principles. These common principles include the devaluation of currency against the dollar, export-led development, privatization, and improved free market practices. States following SAPs are usually obliged to balance their budgets, release import and export limitations, and lessen or stop state subsidies as well as price controls. While the IMF obliges states to make an effort to balance their budgets, they object to the plan of raising taxes. As an alternative, states practicing SAPs are generally required to cut expenses for education, healthcare and social services (Battikha, 2002). These SAPs are the chief cause of such a quarrel over the International Monetary Fund. However, using a liberal view it can be seen that in 'most' of the cases SAPs hurt the states more than they aid. The execution of SAPs has become the source of riots and disputes. Algeria can be taken as an example of it. In October 1988, riots were caused due to the high prices and increased unemployment caused by the implementation of SAPs. During the riots more than 200 people were killed. In order to support this point some more examples would be helpful. Like during the riots in Jordan, due to the increase in prices brought about by SAPs, five citizens were killed in April 1989. In Venezuela, from February 28th to March 2nd, 1989, approximately 600 inhabitants were killed and more than 1000 injured as riots broke out because of the increase in fuel and public transportation prices, caused by SAPs (www.Whirledbank.org). IMF worked in Thailand during 1980s when the state was facing a depression resulted due to a rise in the price of oil, decrease in the costs of agricultural exports, heavy burden of foreign debts and deficit in the external financial accounts. A stabilization program was designed for Thailand which was supported with a strategic structural adjustment program and was implemented with a joint effort of The World Bank and IMF. This helped Thailand to recover from the financial instability it was going through from. Furthermore it is established that the similar instruments which were used by the IMF in tackling
Benefits of Securing a Border Research Paper Example | Topics and Well Written Essays - 1000 words
Benefits of Securing a Border - Research Paper Example As the paper highlights border security has become one of the most contentious aspects in many countries across the globe. A good case study is that of the United States that has benefited tremendously in her Border Patrols. Border patrol in U.S traces its history way back as early as 1904, when mounted watchmen of the U.S. Immigration Service patrolled the border in effort to prevent illegal crossing; however, their efforts were irregular and undertaken only when resources permitted. In the early years of twentieth century, customs violations and intercepting communications to ââ¬Å"the enemyâ⬠seemed to be of a greater concern than enforcing immigration regulations. Agencies charged with the responsibilities of inspecting people and goods entering and leaving noticed that their efforts were totally ineffective without border enforcement between inspection stations. A higher head tax and literacy requirement imposed in 1917 for entry prompted more people to try to enter illega lly. From this paper it is clear that a number of amendments were done to the constitution in line with securing the nationââ¬â¢s border, however, the Eighteenth Amendment to the United States Constitution, prohibiting the importation, transport, manufacture or sale of alcoholic beverages had greater effects. With the passage of this constitutional amendment and the numerical limits placed on immigration to the United States by the Immigration Acts of 1921adn 1924 respectively, the border enforcement was able to receive renewed attention.
Wednesday, October 16, 2019
Business International Law Essay Example | Topics and Well Written Essays - 750 words
Business International Law - Essay Example However, this fund is just made accessible after the country requiring the loan has applied certain structural adjustment program (www.imf.org). Structural Adjustment Programs (also known as SAPs) are economic policies created by each country but having shared common principles. These common principles include the devaluation of currency against the dollar, export-led development, privatization, and improved free market practices. States following SAPs are usually obliged to balance their budgets, release import and export limitations, and lessen or stop state subsidies as well as price controls. While the IMF obliges states to make an effort to balance their budgets, they object to the plan of raising taxes. As an alternative, states practicing SAPs are generally required to cut expenses for education, healthcare and social services (Battikha, 2002). These SAPs are the chief cause of such a quarrel over the International Monetary Fund. However, using a liberal view it can be seen that in 'most' of the cases SAPs hurt the states more than they aid. The execution of SAPs has become the source of riots and disputes. Algeria can be taken as an example of it. In October 1988, riots were caused due to the high prices and increased unemployment caused by the implementation of SAPs. During the riots more than 200 people were killed. In order to support this point some more examples would be helpful. Like during the riots in Jordan, due to the increase in prices brought about by SAPs, five citizens were killed in April 1989. In Venezuela, from February 28th to March 2nd, 1989, approximately 600 inhabitants were killed and more than 1000 injured as riots broke out because of the increase in fuel and public transportation prices, caused by SAPs (www.Whirledbank.org). IMF worked in Thailand during 1980s when the state was facing a depression resulted due to a rise in the price of oil, decrease in the costs of agricultural exports, heavy burden of foreign debts and deficit in the external financial accounts. A stabilization program was designed for Thailand which was supported with a strategic structural adjustment program and was implemented with a joint effort of The World Bank and IMF. This helped Thailand to recover from the financial instability it was going through from. Furthermore it is established that the similar instruments which were used by the IMF in tackling
Tuesday, October 15, 2019
Prepare a two-page paper discussing Dr. Charans insights and how Essay
Prepare a two-page paper discussing Dr. Charans insights and how present-day executive leadership should plan and operate - Essay Example It is also important for the leaders to get full details of their operations so as to be better positioned to defend their core business in the event of economic crisis striking. Short term strategies are advocated so as to be able to deal with the situation. Essentially, there are six leadership traits for hard time which include the following In most cases, revenues for businesses are generated through sales hence the need for the sales people to be as realistic as much as possible. They should scan the current environment and see if they can get an opportunity through evaluating the customersââ¬â¢ potential to buy. These communicate the financial position of the business both internally and externally. Their main role is to communicate clearly and honestly so as to keep the investors and lenders abreast about the situation obtaining on the ground. Another role is to allocate resources according to the current state of economic affairs. There is need to identify the projects that matter as well as set new priorities. To those CEOs who presided over thriving organisations, there is a tendency to believe that they know everything. This over optimism is at time dangerous since they can engage in other risky activities such as debt which can sink the organisation into oblivion. Against this background, CEOs should remember that they are leaders and should inspire their workers even during trying times. They should remind the workers that there is light at the end of the tunnel hence should not despair. There is need to establish respectful relationships with the stakeholders in order to contribute to the firmââ¬â¢s credibility. Information about the situation obtaining on the ground is very important and it should always be truthful. Capable leaders will often have a vision and emerge stronger from a financial crisis.
Monday, October 14, 2019
Would Theodicy work Essay Example for Free
Would Theodicy work Essay A. J Ayer argues that human actions are so because of already preexisting factors in their lives but not as a result of their own free will. He maps these already existing factors such as feelings and past experiences which he calls casual laws as the one that makes people to be who they are. He defends his argument of on the basis that determinism and freewill co-exist in relation when a human behavior is being executed. His definition of free will is that it is the absence of any constraint and thus argues that although people usually are compelled to behave in a certain manner by these casual laws, they remain responsible for their actions since they are not constrained to the choices (Ayer). Theodicy How should evil be viewed in the presence on an omnipotent God who is all good? Could the evil-that which is not good- be from the same God that is all good? How could the all good God ââ¬Ëcreateââ¬â¢ if not create then ââ¬Ëallowââ¬â¢ evil? One could question if it is not him who has created evil, then do his creatures have the potential to create evil? If so, did He create this potential of creating evil in them? If He did why didnââ¬â¢t he create the absolute power in them not to do evil? People are considered to be doing evil based on the choices that they make. The argument is based on the presence of free will on human beings, that is one is absolutely free (without external compulsion) to act in a certain manner. But Ayer does not see it all in this light. He believes that determinism and free will are compatible. To him free will can only be regarded as free if ones actions could have been different and thus because of the chosen cause of action, one is held responsible for his/her actions. He also pointed out that the agent could have been bound to act otherwise if the action motivators were different. But the conditions being as they were for him or her, then the individual acted as he/she did. His argument is that if there happens to be any causal determinism, then it is not possible for the action to be driven by free will. He believes that ones free will is acknowledged, it remains no longer to be free will since to his view, free will should be in the unconscious. He gives an example such as, when one says ââ¬Å"Iââ¬â¢m acting on free willâ⬠, the person ceases to be acting on free will. He identifies this situation as one which has now already been determined. He views that peopleââ¬â¢s use of the term free will is on ordinary sense. He believes that the term freedom needs not to be linked to the meaning and term causality but to constraints. An example is when a man does take some actions at gun point not because they want but because they have been compelled to do it, (Ayer). Another example is that of Kleptomaniac who are not free agents. Unlike a regular thief would do, their minds do not let them decide to steal. Ayer yet gives another example of compulsion neurosis. He says if in such an instance he happens to wake up and walk around the room whether he wants it or not or he has been compelled by someone to do so, then he would not be acting freely. But Ayer argues that if he did it on his own, then it would be free action. For him he held that when it comes to constraints, some generalizations could be made on human behavior, (Hick). He holds that suffering as a child affects ones behavior as an adult. But if this behavior happens to be altered by something that happens in the course of life, then the person is not acting under constraint. An example he gives is a man who decides to forever avoid serious relationship because of having been cheated by a woman in a previous relationship. In this instance the man is conditioned by fear of being hurt and thus is not acting on free will. But the man in question would not agree that his decision is not on free will because he believes that the choice he made was not the only one. This is Ayerââ¬â¢s definition of free will, that is choosing to do something where there were other possibilities of choice even though there could have been a possibility of casual laws. A clear observation of Ayers argument on determinism and free will is that he has attempted to turn free will into that which is not. It should be noted that free will is not simply defined as lack of constraint. A choice that has been made by the virtual of causal necessity cannot be regarded to be more free than the one that is made under logical necessity. Out of this erroneous definition of freewill, Ayer could not be held right on his argument of moral responsibility. Peoples actions are products of numerous causal laws and are thus still being compelled to act in certain manner unlike his view of people being held responsible for their actions because they have acted on free will, (Hick). Conclusion Its common to ask if God is the author of sin and evil in our world. The view of a God who created moral beings and at the same time left them to this probationary economy with the absolute knowledge that they will absolutely fall may seam to be one that could justify theodicy. If the all good God cannot create evil, then the only way that the evil can be looked at it is that is a predestination of a greater glorious good. The attainment of the perceived good may not be because that God is lacking in power to have it without evil but it could be because the glorious end requires sin itself. If this is the case then, the argument that God is the author of sin cannot hold for this reason that if the evil does take place because of his permission, it is not because it the end of the process but rather a part of a process towards the real ââ¬Ëendââ¬â¢ -omnipotent and ââ¬Ëall goodnessââ¬â¢- which in short is back to God. God cannot thus be the author of evil but rather evil can be regarded as the part of that process that is towards all good. If God permits it then, it is not to the denial of Himself, the all good, but an affirmation that He is all good since everything, even evil leads all back to Him.
Sunday, October 13, 2019
Symptoms And Treatments In Cystic Fibrosis
Symptoms And Treatments In Cystic Fibrosis Abstract Cystic fibrosis (CF) is one of the most common genetically inherited diseases which can cause premature death in western populations, with 1 in 2000-3000 new born babies being found to be affected by Cystic fibrosis in Europe [1]. The disease is caused by defective chloride ion channels along the epithelial membrane of the lungs, pancreas and other organs; although there are several hypotheses as to how this dysfunction specifically gives rise to the typical symptoms. The complications associated with the disease are varied, the most significant being the build up of abnormally thick excess mucus which can cause impaired function of the lungs and other major organs. Fortunately research into new treatments has significantly improved the life expectancy of people suffering from this disease. This essay discusses the causes Introduction The name cystic fibrosis refers to the generation of cysts in the pancreas and the formation of excess fibrous connective tissue in the lungs. The internal organs which suffer the most damage as a result of this disease are the lungs and the pancreas; although a variety of other organs are also affected. The first clinical recognition of cystic fibrosis didnt occur until the 1930s when its symptoms were observed and characterised by Dr. Dorothy Anderson. The recessive nature of the disease was confirmed in the mid-forties after an investigation involving over one hundred families; although the defective gene that causes the disease wasnt isolated for another forty years when it was discovered in 1989 by reverse genetics. After the breakthrough in the forties general understanding of the disease increased steadily over the next couple of decades with a major clinical advancements in diagnostics occurring in the fifties with the development of the sweat test. As cystic fibrosis is the result of an autosomal recessive disorder, the sufferer will have to of inherited two copies of the mutated gene (one from each parent) in order to be affected by the disease. The mutation takes place in a single gene on chromosome 7. This faulty gene leads to the development of a defective cystic fibrosis transmembrane conductance regulator (CFTR) protein. In healthy people the CFTR proteins form ion channels to transport chlorine ions across the epithelial membrane of the lungs, pancreas, sweat glands and other organs. It is also thought to regulate the activity of other chlorine-selective channels and some cation-selective (sodium ion) channels. Ions can then pass through these channels thereby maintaining the water potential of the cells. When the fine balance of ion concentration is affected less water is able to pass across the epithelial membrane by osmosis causing excess and highly viscous mucus to build up in the affected organs, resulting in severe long-term respiratory and digestive problems. The human lungs are adapted for use in aerobic respiration by providing a thin, moist surface for gas exchange to take place between the pulmonary arteries and the external environment. For gas exchange to be effective the respiratory surface must comply with Ficks law which requires that the surface area is large, moist and thin to enhance permeability. The resulting fibrosis caused by the disease greatly affects the permeability of the lungs and hence reduces their capacity for gas exchange. Molecular mechanisms There are over 1500 types of mutation which can cause a defect in the CFTR protein, the most common of which is a deletion of phenylalanine at position 508 (à ¢Ãâ â⬠F508) which Is the cause of approximately two-thirds of CF cases. The mutations are categorised into six classes determined by their impact on the resulting functionality of the CFTR channels, ranging from reduced to complete non-function. Class I, II and III mutations all result in the absence or substantial reduction of functional CFTR. Class I mutations cause a complete lack of protein production due to premature stop codons arising in the genetic code whereas class II mutations produce a protein that doesnt fold properly and so is consequently degraded by the cell. In a class III mutation the lack of effective binding with ATP molecules leads to the defective regulation of CFTR and so again is classified as being non-functional. Classes IV and V still permit the development of functional CFTR albeit with reduced capacity for chloride ion transport or with reduced production of functional CFTR in general due to promoter mutations that decrease transcription [2]. Class VI mutations also produce functional CFTR although its degradation is greatly accelerated. The F508 deletion results in a class II mutation. There are four main hypotheses as to how this defective gene causes disease although it is not known whether the disease is caused by one or a combination these hypotheses. Two of these, the low volume and high salt hypotheses, provide a detailed description of the complications that arise as a result of faulty CFTR by taking into account the composition of airway surface liquid (ASL). Low volume hypothesis In the case of the low volume hypothesis it was postulated that there is little to no difference in the salt concentration of ASL between healthy people and those suffering from cystic fibrosis. This hypothesis suggests that the symptoms of cystic fibrosis are caused by a dysfunction of the CFTR gene resulting in damaged or ineffective sodium ion channels. The damage caused is ergogenic and reduces the inhibition of the ion channels leading to the excessive movement of sodium ions from the ASL into the airways. The increased concentration of positively charged sodium ions in the airways then drives the absorption of chlorine ions and water, reducing the volume of ASL and dehydrating mucus. The dehydrated mucus becomes highly viscous and the cilia present on epithelial cells which are used to aid the clearance of mucus and to increase lung surface area become compressed by the mucosal build up. This compression of cilia inhibits the clearance of mucus which then continues to build up, further reducing the lung surface area. The excess mucus can also form hypoxic niches that can harbour colonies of pseudomonas aeruginosa. Build up of mucus physically reduces the lung surface area affecting the efficiency of gas exchange. The mucus build up also increases the compression of cilia on epithelial cells which inhibits clearance by cilia and coughing. High salt hypothesis The high salt hypothesis assumes that the airway surface liquid of healthy individuals has a relatively low salt concentration when compared to the ASL of cystic fibrosis sufferers. It suggests that the symptoms of the disease are caused by the disruption or complete absence of CFTR function which causes excess sodium and chloride ions to be retained in the ASL. This increased retention of chloride ions leads to the ASL having an abnormally negatively charged composition. This abnormality impairs the activity of the bodys natural bactericidal enzymes such as lysozyme which rely on electrostatic interactions to attach to the bacterial cell walls; thus allowing bacterial infection to persist in the hypoxic niches formed within the lungs. Abnormally high inflammation It has been speculated that the defective CFTR itself may be the cause of excessive inflammation in the airways. However there is limited evidence to suggest that the defective CFTR is a cause of excessive inflammation in itself but rather that it interferes with the regulation of autophagy. Autophagy is the process by which defective proteins are degraded in order to maintain the balance between the recycling and synthesis of cellular products, for example the degradation of defective CFTR by the cells own lysosomes. Research indicates that large amounts of defective CFTR inhibits autophagy, leading to an accumulation of aggresomes which can cause inflammation in the lungs [3]. The resulting inflammation is what gives rise to the characteristic scarring of lung tissue. CFTR bind with P. Aeruginosa Chronic bacterial infection is common amongst all cystic fibrosis sufferers, specifically the bacterial species pseudomonas aeruginosa which binds readily to the CFTR protein. In healthy people the body initiates an immune response in order to fight off the infection. In cystic fibrosis suffers there is enhanced binding between p. Aeruginosa and the CFTR protein, the bacterium is also able to bind without initiating an immune response. The compromised immune response combined with reduced ability to clear mucus due to compressed cilia further increases the risk of severe infection. Symptoms Visible characteristics typical amongst suffers include a slightly meagre appearance due to inefficient absorption of nutrients and the famously salty sweat used to confirm CF diagnosis. Low levels of oxygen in the tissues due to impaired gas exchange between the lungs and the bloodstream can cause clubbing of the fingers and toes Salty sweat The salty sweat associated with the disease like so many of its symptoms is again caused by faulty CFTR present on the sweat ducts. As sodium ions leave the sweat ducts through ion channels chloride ions follow through them through the CFTR protein channels. However, in cystic fibrosis patients dysfunctional CFTR channels prevent the outward flow of chloride ions from the sweat ducts. The resulting high chloride ion concentration in sweat ducts creates an electrochemical gradient which pulls more positively charged sodium ions into the ducts where the ions combine to form salt (NaCl). The salt is then secreted through pores in the skin resulting in very salty sweat as very little NaCl is reabsorbed. Salt sweat concentration of greater than 60mEq/L is generally considered significant enough to make a diagnosis, although further test may be required. Although poor growth can pose its own health risks the most severe symptoms are caused by the diseases capacity to cause damage to the internal organs. Endocrine CF is commonly referred to as an exocrine disorder meaning the resulting dysfunction affects glands which secrete their products through a duct to the surface of the body or of an organ, sweat glands and pancreatic ducts being an example of this. However some complications can arise in the bodys endocrine glands, glands which secrete their product directly into the bloodstream. Disorders of the endocrine glands tend to affect the secretion of hormones. Damage to the islets of langerhans within the pancreas can impair the secretion of insulin which can eventually lead to CF related diabetes. Pulmonary Lungs are the predominant source of infection, vulnerable to different species of bacteria although P. Aeruginosa becomes predominant; eventually these bacterial colonies form a biofilm which is difficult to remove with antibiotic treatments. The thickening of mucus creates environmental niches suitable for harbouring bacteria. High levels of infection result in an inflammatory response which often leads to extensive tissue damage and scarring regarded as the characteristic fibrosis of the lungs. The resulting fibrosis damages the epithelium of the lungs, making gas-exchange inefficient. Thick mucus also physically reduces the surface area Implications for other organs The lungs arent the only organs that suffer damage as a result of cystic fibrosis Diverse range of other organs affected, majority of these form a part of the alimentary system Lacking digestive enzymes in the intestines Absence of these digestive enzymes impair patients ability to breakdown and therefore digest their food. This generally results in poor growth but in extreme cases can cause severe malnutrition. Alimentary system all digestive systems The formation of cysts blocks ducts in the liver and pancreas preventing the secretion of essential digestive enzymes and hormones. Blocked ducts prevent secretion of enzymes/hormones? Mainly the pancreas which affects absorption of nutrients and can lead to poor growth in suffers Blockage of ducts in the liver New born babies can suffer from meconium ileus, an inability to pass their first faeces (meconium). The resulting ileus can cause blockages in the intestines that can cause rectal prolapse due to the strain involved in producing a bowel movement. Common associations between cases of meconium ileus and CF led to it being used as a postnatal diagnostic technique. Excess viscous mucus isnt only a problem in the lungs. Organs of the alimentary system can also be affected. Thick mucus can block pancreatic ducts preventing the secretion of vital digestive enzymes into the duodenum. The body is then unable to effectively extract nutrients from the ingested foods. Malabsorption is a common symptom of CF generally resulting in poor growth but in extreme cases can cause severe malnutrition. Fertility problems Fertility problems related to CF usually occur before birth whilst the foetus is still developing. Blocking of or complete absence of the connective tube (vas deferens) between the testes and ejaculatory ducts in males means that although they are not sterile they are unable to conceive children by traditional intercourse. In women thick mucus can cause blockages in the cervix or their ovulation cycle may be disrupted malnutrition as a result of CF related enzyme deficiencies. More than 95% of males with CF are infertile. Percentage of CF infertile source world health organisation Treatments Unfortunately there is currently no cure for CF however there are several treatments that can alleviate some of the symptoms associated with the disease, such as the use of hypertonic saline and enzyme replacement. Treatments such as gene therapy are more geared towards creating a permanent cure for CF, although at this moment in time the technology has not been perfected. Pharmacological treatments Fortunately the CFTRs are not the only chloride ion channels available on lung surface epithelium. Certain drugs can stimulate these other channels. Rcjournal. Stimulate the release of calcium or inhibit sodium channels to offset negative effects of whatever hypothesis. Hypertonic saline Major complications of CF stem from the imbalance in ion concentrations caused by the faulty CFTR gene. From this knowledge a line of treatments were developed in order to restore the ionic imbalance and hence improve the bodys ability to clear thick mucus from the lungs. The answer would need to be a sterile solution; high in salts that could be inhaled to replace the ions which werent being transported across the CFTR channels. The solution, hyper tonic saline, is a cheap and effective treatment for reducing the viscosity of mucus in the lungs. After it is inhaled the solution works by creating an osmotic gradient, drawing water into the airways, rehydrating the mucus causing blockages and reducing its viscosity hence making it easier to cleared and coughed up. Enzyme replacement Enzymes can be *injected* to restore the deficiency created by blockages of pancreatic ducts. Patients undergoing enzyme replacement therapy can expect to see improvements in growth, weight gain and general health as many illnesses arise from poor absorption of nutrients. Nutritional supplements can also be taken to replace those not being absorbed normally. Important short term treatments are giving nutritional supplements to sufferers to relieve malnourishment and promote healthy growth Nutritional plans generally involve high calorie diets rich in vitamins such as vitamin D to develop strong bones and prevent osteoporosis. Gene therapy Soon after the discovery of the defective gene in 1989 efforts were invested in finding a therapy that could target the disease at its genetic roots. Discovery of an effective method of gene therapy would open a virtual goldmine in treating not only cystic fibrosis but also other genetic diseases. One of the current gene therapy techniques for the treatment of CF involves the use of adenoviruses carrying vectors containing corrected copies of the CFTR gene. The adenoviruses carry double stranded DNA which is deposited in the nucleus of the host cell and then transcribed in the same way as the host cells own DNA. However, as this is an example of somatic gene therapy, the DNA of the adenovirus wont integrate with the host genome and the gene will not continue to be expressed after cellular division. This means the effects are not permanent and patients will require subsequent treatments to maintain the effect. There are of course risks associated with the use of viruses to incorporate functional DNA. Even though the viruses being used are non-pathogenic the presence of a foreign body can still initiate an immune response; the resulting inflammation can be dangerous for patients who are already at high risk of excessive inflammation due to immunocomprimisation. An alternative to adenoviruses are adeno-associated viruses (AAV). AAV vectors are non-pathogenic and have been shown to have a lower prevalence to neutralising antibodies when com pared to adenoviruses in vitro [4]. However they do have a relatively small genome of ~4.8 kilobases, with most gene treatments requiring the complete replacement of the viral genome. As a result of this, research is being targeted towards more effective means of gene therapy with tests being carried out with AAV and lipid-vectors. There is a trade off between the effectiveness of the method used to induce the vector. Viral vectors are more effective at integrating the vector into the host DNA compared to lipid vectors, but there is the increased risk of an immune response. Lung transplant In the most severe cases where patients are suffering from chronic infection lung transplants can be carried out where appropriate. In these cases both lungs need to be transplanted in order to prevent the new lung from being contaminated by existing bacterial populations currently present in the patient. Antibiotics Antibiotics tend to be used prophylacticaly as a pre-emptive measure for preventing infection. One common type of drugs used in treatments are macrolide antibiotics can suppress obstructive secretions in airways The macrolide antibiotics work by binding to the 50s subunit of the bacterial ribosome, thereby inhibiting protein synthesis. Conclusion The overall outlook for patients with CF has improved dramatically over the past eighty years since the first clinical recognition in the 1930s. A greater understanding of genetics has enhanced both the fields of clinical diagnostics and treatments. The future of treatments points towards gene therapy, we currently have the technology to do this but further research is needed to overcome the major obstacles such as more efficient transfer and getting the gene expression to last longer. [*http://www.who.int/genomics/public/geneticdiseases/en/index2.html#CF] http://www.medscape.com/viewarticle/576200_2 http://www.nature.com/ncb/journal/v12/n9/full/ncb2090.html http://www.nature.com/gt/journal/v6/n9/full/3300994a.html Figure 1. Sweat chloride concentrations related to cystic fibrosis (CF) diagnosis. Revised and reprinted by permission from Davis PB. Cystic fibrosis. Pediatr Rev 2001;22:257-264.Figure 1
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