Inflammatory Bowel Disease: Types, Causes and Effects

Inflammatory Bowel Disease: Types, Causes and Effects Chapter 1: THE INFLAMMATORY BOWEL DISEASE WHAT IS INFLAMMATORY BOWEL DISEASE Inflammatory bowel disease (IBD) means chronic inflammation of all or part of your digestive tract. IBD can be classified into two, which is, ulcerative colitis and Crohns disease. IBD is very painful and debilitating, and can sometimes lead to life-threatening complications. The IBD is called an autoimmune disease because the body’s immune system attacks the digestive system. The disease is so severe that it may cause abdominal pain, bloody diarrhea, cramps and fever. This is however different from Irritable Bowel Syndrome (IBS). DIFFERENCE BETWEEN INFLAMMATORY BOWEL DISEASE (IBD) AND INLAMMATORY BOWEL SYNDROME (IBS) The difference between the IBS and the IBD is that IBD is structural, but IBS is not. If the gut is examined by x-ray, endoscopy, biopsy or surgery, structural damage to the gut can be seen. In IBD, the damage is caused by the inflammation and may require heavy duty medication, or even surgery. Whereas in IBS, the examination of the gut of a person having IBS would help detect nothing. It can only be detected by gut symptoms. These may include abdominal cramps or pain, harder or looser bowel movements than average, excess gas, diarrhea and constipation – or alternating between the two. Both of these affect people of all ages but young people are mostly affected. Females have more chances of having IBS. IBD has no gender preference but is mostly found in Jews and people from Northern Europe. IBS is a worldwide disorder, while IBD is prominent in the planet’s temperate zones. In IBD, the gut is damaged by chronic inflammation. The damage is fought by the defense mechanism of the body resulting in fever and malaise. The intestines are disrupted, they may bleed and anemia is common too. There is inability to eat during attacks, inflammation is caused which results in wasting of energy, ultimately resulting in weight loss and malnutrition. IBS cannot be identified by findings of physical examination. However, the structural damage caused by IBD is also capable of producing striking physical findings like a mass in the abdomen, or the symptoms such as that of weight loss and anemia. Other differences include the need for surgery in IBD, which is not required in IBS. IBS does not induce complications in the gut, skin, joints and eyes, but IBD does. CROHN’S DISEASE This is the type of IBD that may involve any part(s) of the gastrointestinal tract, ranging from mouth to anus. Listed below are a few characteristic features: Inflammation usually occurs in patches. The pain is usually experienced in the lower right abdomen. The colon may turn thick and might appear to be rocky. Ulcers in and along the digestive tract are very deep, sometimes extending into every layer of the bowel wall. During bowel movement, rectal bleeding is not common. Ulcerative colitis is the second type of IBD, which is taken up in the subsequent chapters. Chapter 2: ULCERATIVE COLITIS Defining Ulcerative colitis â€Å"Colitis† means the inflammation of the colon, or more largely, inflammation of the large intestine ( that comprises of colon, caecum and rectum). Ulcerative colitis is a disease of the colon, which is the largest part of the large intestine, characterized by ulcers (open sores). These ulcers are painful wounds, they may bleed and also produce mucus and pus. The mucosa (inner lining) of the intestine becomes red and swollen. The rectal area is most severely affected. If the lining of the colon is damaged, it may cause bloody diarrhea. Where Crohn’s disease can affect almost any part of the digestive tract, Ulcerative colitis only affects the large intestine. Crohn’s disease can be treated by removing the affected parts and reconnecting the healthy ones. Whereas to treat ulcerative colitis, one may have to remove the large intestine completely (called colectomy). It can occur at highly irregular intervals, at times, with symptoms extremely severe, and sometimes, no symptoms at all. Ulcerative Colitis- An autoimmune condition In autoimmunity, an organism fails to recognize its own constituent parts as â€Å"self, and thus leads to an immune response against its own tissues and cells. Such diseases are termed as autoimmune diseases. In other words, our body’s defense mechanism goes wrong and attacks its own healthy tissue. There are harmless bacteria present inside the colon, which are mistaken to be harmful by the defense mechanism, and are attacked, leading to inflammation. Classifying Ulcerative Colitis Ulcerative Proctitis This is Ulcerative colitis in its mildest form. There is inflammation only within the rectal area. The various signs and symptoms are as follows: Rectal pain Rectal bleeding There is an urge to move the bowels but inability to do so. Proctosigmoiditis This involves the lower end of the colon, that is, the sigmoid colon and the rectum. The signs and symptoms are as follows: Abdominal pain Bloody diarrhea Abdominal cramps Constant urge to go to the toilet Left sided colitis There in inflammation in the rectum, up on the left side along the sigmoid colon and the descending colon. The signs and symptoms are: Abdominal cramping on the left side Bloody diarrhea Weight loss Pancolitis (Universal colitis) This involves and affects the whole colon. The signs and symptoms are: Bloody diarrhea (there may be severe bouts) Abdominal pain Abdominal cramps Weight loss Fatigue Fulminant Colitis This is the most rare form of colitis and it can be life threatening. It affects the whole colon. Patients suffering from fulminant colitis are at a constant risk of toxic megacolon (the colon becomes swollen, or bloated, or distended) and colon rupture. The signs and symptoms are as follows: Severe diarrhea, that can lead to shock and dehydration Severe pain SYMPTOMS OF ULCERATIVE COLITIS The Gastrointestinal symptoms include: Diarrhea with blood and mucus. This implies the gradual onset of the disease which may persist for an extended period, maybe weeks. If rectal examination is conducted, blood may be found. The patients also suffer from drastic weight loss. Due to the inflammation and extreme loss of blood from the gastrointestinal tract, anaemia may occur. There may be mild abdominal pain, or painful bowel movements accompanied with painful abdominal cramping. One may even experience fatigue and loss of appetite. One may experience very mild or almost no symptoms, called â€Å"remission†, which may be followed by symptoms that are troublesome, called â€Å"flare-ups† or â€Å"relapses†. These may be triggered by stress. Flare-ups may be very troublesome, in which patients may have to empty their bowels about six times or more each day. Heartbeat may be fast or irregular, accompanied by shortness of breath and high fever. Severity of the disease Mild disease This means less than four stools each day. Blood may be present or absent. Patient may experience mild cramping and abdominal pain. The patient may feel constipated, with a continuous feeling of needing to empty the bowel, with cramping or pain and little or almost no fecal output. Moderate disease This means more than four stools each day. Patient also displays signs of anemia, fever around 100 to 102 degrees Fahrenheit. Severe Disease This means around six stools with blood each day, implying observable bowel movement, toxicity demonstrated in the form of fever, anaemia and tachycardia. Fulminant Disease This means more than or equal to ten bowel movements each day, accompanied by continuous bleeding, abdominal tenderness, toxicity, colonic dilation and blood transfusion is often required. Patients may have toxic megacolon as the inflammation extends beyond the mucosal layer. At times, the serous membrane also gets involved causing colonic perforation. If not treated, fulminant disease may lead to death. Extraintestinal Symptoms As ulcerative colitis is an autoimmune disease, patients may develop symptoms as well as complications outside the colon. These include: Ulcers in the mouth. Opthalmic: Irritated and red eyes, or inflammation o iris called iritis. Musculoskeletal: Swollen joints (arthritis). These may be large joints, or small joints of hands or feet. Or joints of the spine. Cutaneous: Inflammation of the subcutaneous tissue. Painful and ulcerating lesion of the skin. A deformity of the ends of the fingers (Clubbing). Inflammation of the bile ducts (Primary Sclerosing Cholangitis). Chapter 3: Causes of Ulcerative Colitis The causes of Ulcerative Colitis are still not known. Yet, the possible causes are listed below: GENETICS The disease can be inherited if one has a close relative suffering from the disease. Hence it can be found in the family. The regions of the genome that can be linked to this disease are the chromosome number 1, 3, 5, 6, 12, 14, 16, 19. Since none of these have been faulty continuously, it has led to a conclusion that the disease occurs due to a combination of various genes. One of the regions, for example, has been linked to ulcerative colitis is chromosome band 1p36. ENVIRONMENTAL FACTORS Inflammation may be encouraged by diet. For example, if there is a large intake of vitamin b6 and unsaturated fat affect the development of ulcerative colitis. There are many other discovered dietary factors which may lead to the relapse or development of the disease, like meat protein and alcoholic beverages. Vitamin D deficiency is also a leading cause of the disease. Breastfeeding may also lead to the development of the disease. The role of Sulphur in Ulcerative Colitis Sulphur is found in many foods and substances like milk, eggs, cheese, mayonnaise. It is also used as a food preservative because it stabilizes protein structures. It also prevents microbial growth during fermentation of wine and beer. Bacteria that are present in the bowel convert the sulphur present in the food to hydrogen sulphide, which is called fermentation. This substance is harmful as it can cause abdominal pain and urgent and frequent bowel movements. Because of the already existing inflammation of the bowel lining, patients suffering from ulcerative colitis find it difficult to break down the gas as they produce more hydrogen sulphide than normal. This toxic substance, in high amounts, reduces the protective unction of the cells that are lining the bowel. It can also cause cell death and induce ulceration in the superficial mucosa of the intestine. Hence the cells lining the colon are harmed. IMMUNE SYSTEM Theories suggest that a virus or a bacterium also may trigger ulcerative colitis as the digestive tract may become inflamed when the immune system tries to get rid of the invading microorganism (pathogen). This inflammation is caused due to the release of white blood cells to destroy the present pathogen. This may lead to an autoimmune reaction/condition in which the body produces an immune response even during the absence of the pathogen. This happens because the body tries to eliminate pathogens which are either gut friendly, or non-existent. RISK FACTORS The factors that raise the risk of developing Ulcerative colitis are as follows: Age: Though it may affect people at any and every age, it is more commonly found in people aged 15 to 30. Genetics: If someone has a close relative with the Crohn’s disease or ulcerative colitis, they are at a high risk of development of the disease. Isotretinoin: The treatment of cystic acne is often done with the help of this medicine. It can cure other kinds of acne too, but it increases the risk of this disease. The medicine is also called Accutane. Amnesteem, Sotret and Claravis (These are the various other brand names). Appendectomy: The removal of the appendix may lead to the reduction of the risk of developing ulcerative colitis but an increased risk of Crohn’s disease. Chapter 4: DIAGNOSIS Ulcerative colitis is diagnosed only when the possible signs and symptoms of infection, Crohn’s disease, irritable bowel syndrome (IBS) and colon cancer have been ruled out. The following tests are carried out: BLOOD TESTS They help to check anaemia, and also help to diagnose the name of the bowel disease the patient has. STOOL SAMPLE If there are white blood cells present in the stool, it implies that the patient is suffering from an inflammatory disease, possibly ulcerative colitis. It also helps rule out other diseases, like those caused by bacteria, viruses and parasites. Clostridium difficile usually causes diarrhea but also common amongst people suffering from ulcerative colitis. Bowel infection can also be checked this way. COLONOSCOPY The entire colon can be viewed using a flexible, thin and lighted tube which has a camera attached to it. Small tissue samples are also taken (called biopsy) so that a laboratory analysis can be conducted and ulcerative colitis may be diagnosed. SIGMOIDOSCOPY This test is done if the colon is inflamed severely. A thin, lighted and flexible tube is used to examine the last portion of the colon, the sigmoid. But the drawback of this procedure is that the problems occurring higher up the colon may be missed and a full picture of the affected colon is not achieved. BARIUM ENEMA The entire large intestine can be examined using an X-Ray. A contrast solution of barium accompanied with some air is placed into the bowel with the help of an enema. Once the barium coats the entire lining of the colon, rectum and a part of the large intestine, it creates a silhouette. This is a dangerous test and hence rarely used because the pressure that is applied to inflate the colon and coat it may lead to its rupture. X-RAY An X-ray of the abdominal area can be done to rule out the possibility of toxic megacolon and perforation as these conditions may appear because of the severe symptoms. CT SCAN This scan is carried out to check the extent of inflammation of the colon. The abdomen and pelvis are scanned if complications due to ulcerative colitis are observed or an inflamed small intestine that may be because of Crohn’s disease. VIDEO CAPSULE ENDOSCOPY (VCE) In this test, a patient swallows a capsule containing a camera which takes pictures of the intestine as it travels through it and sends them to a recorder wirelessly. The pictures can then be reviewed. Chapter 5: TREATMENT The treatment of ulcerative colitis is done on the basis of the severity of the disease. It mainly consists of changes in the diet and medication. If symptoms are found to be severe and long lasting, more medicines may be required or even surgery. But medicines cannot completely the disease. They can only minimize the risk of cancer, induce remissions and maintain them and improve the quality of life. AMINOSALICYLATES These are anti- inflammatory drugs that are used to induce and maintain remission. 5-aminosalicylic acid (5- ASA) produces the anti-inflammatory action. Examples of aminosalicylates are- MESALAZINE: Also called Pentasa, Octasa and Asacol SULFASALAZINE: This belongs to a class of antibiotics and it decomposed in the intestine to release 5-ASA. Since this substance is not entirely absorbed by the intestine, it gives a topical relief. CORTICOSTEROIDS These are often used with 5-ASA drugs to induce remission of ulcerative colitis. These work by the blocking the parts where leukocyte adhesion cascade occurs to induce inflammation. These have many side effects like the puffiness on the face, called â€Å"moon face†, and manic behavior. It may also cause bipolar disorder, inducing periods of elevated mood and depression. Examples include Cortisone, Hydrocortisone, Prednisone. IMMUNOSUPPRESSIVE DRUGS These inhibit the immune system. They stop cell division of white blood cells that occur as an immune response. Examples are: Mercaptopurine, Methotrexate, Azathioprine. DIET MODIFICATION Fresh fruit, carbonated drink and caffeine should be avoided by patients suffering from diarrhea and abdominal cramping. Some patients show lactose intolerance (they are not able to digest lactose) hence they can’t consume lactose. To supplement the bone loss, calcium is given to them. The gastrointestinal and auto-immune symptoms can be helped by using the Specific Carbohydrate Diet that allows only the use of monosaccharides and not the other carbohydrates. At times due to metabolic defects, Hydrogen Peroxide may build up underneath the membrane that usually protects the walls of the intestine from the bacteria that are present. To protect ourselves from these oxidants, a need to take antioxidants arises. These include vitamins A, E, C, Selenium and manganese. HERBAL MEDICINE While Kampo is a medicine that is used in Japan, Boswellia is and Ayurvedic medicine that can be used as an alternative to other drugs. Medicinal cannabis can also be used as it helps reducing abdominal discomfort and abdominal irritability caused by ulcerative colitis. HELMINTHIC THERAPY Sometimes, parasites may help in the reduction of the immune response of the intestine. Whipworm may be used for this purpose. Reduction of immune response may help in the complete elimination of ulcerative colitis. SURGERY Colectomy is required to remove all or a part of the colon when it gets infected and begins to spread the infection to other parts. It can be classified as follows: TOTAL COLECTOMY: The entire colon is removed PARTIAL COLECTOMY: The entire colon is not removed, but only a part of it is. HEMICOLECTOMY: Removal of the left or right part of the colon PROCTOCOLECTOMY: Removal of the colon as well as the rectum. Once colectomy is performed, the remaining portions of the gastrointestinal tract are reattached in order to allow the waste to be eliminated from the body.

Contract la w

Businesses need to plan their affairs relying on the fact that contracts can be enforced In order to malting the web of Interdependent relationships. Contracts are a way of enforcing agreements. One needs to anticipate the future as In thinking what can go right and what can go wrong, cause It allows one to project into the future e. G wanting things to work out a certain way in the future, and so a contract can be used to have people do things into the future or protect you from things that can go wrong in the future.It's not Just a reactive thing but It gives one the possibility of planning Into the future. It has a wealth mastication function also since it is an exchange of goods and services to someone who values them the most such as one values the object In a store more than the money in ones pocket and the store values the money In ones pocket than the object they have in their store (objective and subjective approach egg when determining the value of something).This as such c reates wealth in society by moving goods and services to those who value it more. One flaw however is transaction cost such as advertisement cost etc, so contracts do not come for free it takes time and effort. The biggest transaction cost in interact Is legal cost. Efficiency – certainty (structure) – needed for a proper contract. Is there and agreement? – Objective approach is taken, what would a neutral person think looking at the transaction.A Judge does not have to prove fault or negligence the only thing required in a contract case is one agreeing to do one thing in contract but fails to follow that agreement and as such one is entitled to sue the other in breach of contract. No need for fault or intentional wrongdoing. It all flows from agreement, not about fault, it is about agreement and breach of the said agreement. Is it legally enforceable? Some agreements are Just not enforced legally such as two friends making an agreement. Entitled to sue and get a remedy when another person to that contract fails to carry out their part.Contract is important due to the remedy that is given. Remedy – one remedy is being put back in the place you were before the contract was executed, another is where one is put in the expected position meaning the position one would be in had the contract been properly carried out usually wanted by the claimants, as it relates to the defendant one asks how much they have gained as in getting more money but the principle is that one should not gain from reaching a contract, another approach is the moral approach where it is immoral to breach a promise since a contract is where promises are made.Punitive (punishing for wrong performance) is usually non-existent however countries such as the USA suing for punitive damages is available. Contract law takes an expectation approach rather than a reliance approach. Hire someone agrees to pay a fee for their service, they spent some money advertising the event and selling the ticket, performer offered a better deal and so breach the contract by taking the other Job and as such they breached the contract for their original performance and so tickets needed to be refunded.As it relates to reliance approach one can claim money was waste don advertisement and service fee all of which are reliance loss however as it relates to expectation one looks at the money that they could have gained from the ticket selling whilst still taking into consideration the money paid for advertising and service and so one is claiming for the expectation loss for the ticket that could have been sold. Either they person performs what they promise or one is put in the position had he performed it properly.Expectation interest allows one to plan based on the contract. Reliance interest – expectation protect ones ability to rely on a contract. As it relates to reliance loss one has to prove that had he not made the contract with one he would have made the con tract with the same benefit from another agreement. Reliance can be used also where the contract is formed in a unfair manner such as duress since one would not want to be put in the position had the contract been carried out one would want to be put in a position before the contract was made.

General Evidence To Ipo Under-Pricing

During the 1980s, the market expected an average of 11% returns on the initial public offerings (IPOs) within the first week of opening, which subsequently almost reached up to 21% during the period of 1991-1999. During the magical period of 1999 – 2000, the returns were almost 66%.   These effects can be largely credited to the amendments in the composition of a number of listed companies appearing as public.What is the most prominent reason behind the harsh under pricing of initial public offerings where the returns have been unexpectedly higher?According to the statistics, the IPO under pricing had almost doubled from 7% to 16% from the 1980’s to the late 1990’s. In general, the increase in the under pricing can be pointed towards the previously concealed group troubles between underwriters and issuing firms.Stating in other words, the problems between the two, that were initially not present on the main scene became of overriding importance during the 1999 – 2000. These two propositions are often referred to as the varying composition theory and the agency theory.The first theory of varying composition is supported by the postulation that dicey and unsafe IPO’s will be obviously underpriced by more than less dicey IPO’s. If the percentage of IPOs that correspond to unsafe stocks swells up, then the average under pricing ought to increase (Ritter (1983)).As a note, the number of IPO’s from the Information technology sector has risen up with time. Another significant point to note was that, there exists no proof about the companies which were appearing as public during the late eighties was actually older than those who went into the public sector during the nineties.The average age of an issuing company was around 7 years during the 1980s and 8 years during the 1990s, before it came down to 5 years during 1999-2000 (â€Å"the internet bubble or the magical period†). An analogous outline holds for sale s structure, that there was no secular inclination in the average sales of public companies.In contrast to the late 1980’s, the IPOs which were administered by high profile investment banks / underwriters in the 1990’s, were more highly underpriced than IPO’s which were linked to inferior status under writers or investment institutions.This phenomenon was explained as- since the underwriting in the IPO business became more profitable due to the augmented enthusiasm of firms to put down more money on the table. (Money on the table is defined as – the first-day price change (offer price to close) times the number of shares issued).As a result the underwriters / investment institutions made more profit from the money that was left on the table with the help of a rent-seeking action of buy-side investors. Moreover the market investors are prepared to give higher rates to the underwriters in order to receive IPO allocations.At the same time, the issuing compan ies are also ready to accept higher under pricing from high profile underwriters because of augmentation in the apparent significance of market analyst reporting and superior capital levels.One more reason that has come into light about the causes of IPO under pricing is that the under writers actually want to under price the issue in spite of the gross spread profits that they sacrifice.At the same the issuing firms most of the times do not try to bargain for a higher offer price when they are sure that the demand for the issue will be high enough. A number of firms went public which resulted in an obvious under pricing of IPO’s.According to Lungqist and Wilhelm (2003) as stated in a paper, that the increase in the IPO under pricing during the period of 1996 to 2000, was mainly due to the increased sharing programs like – the friends and family share allotment programs.Even more the number of shares that were owned by the company seniors like managers, CEO and venture capitalists had decreased by a significant amount, which offered fewer profits to them to stay away from harsh under pricing.Lungqist and Wilhelm further advocate that ruthless under pricing of IPO’s is also a consequence of a blend of premeditated under pricing by the issuing firms, who often assume to observe it as a way of drawing market awareness, and essential under pricing in order to pull out information from probable investors about demand for the IPO.In the year 2005, the European market had heaved up more money with the help of the initial public offerings (IPOs) and were able to create a center of attention for a large number of international IPOs as compared to the US exchanges.This increase was due to the increment in the business activities at the London Stock Exchange and in particular to the AIM, which were accountable for more than 53% of the total IPO’s in the year 2005.The London stock exchange has been the most active of the IPO world markets and a s figures suggest, the IPO activity at the LSE is much higher than all the US markets. This paper makes an attempt to further study the under pricing in the London Stock Exchange (LSE) Main market and the AIM.As the study suggests, the cost of raising IPO in the LSE is quite cheaper than on the US markets and there are some reasons that are evidence to this fact. London’s position in terms of measurable costs is similar to that of Euronext and Deutsche Boerse.UNDER PRICING OF IPO – LONDON STOCK EXCHANGEThe capital trading markets all over the world are experiencing a new level of global integration as obstacles to the flow of international funds are being removed slowly. As a result, firms now possess high amounts of flexibility while listing and raising capital.There are locations / markets that can actually prove to be quite cheaper for raising capital. This has given an opportunity to the companies as to select their own choice of trading market around the world kee ping in mind, cost of raising capital, equity, debt and market advantages.The decision of the firms to select a particular market depends upon varied issues like the market size, directness, level of expertise accessible in its financial centre, and the listing procedure involved.Also, there exist several ways to float a company – the choices of which are highly affected by the size of the company, the risk involved, and the authoritarian planning and procedures in each country.   The most common of all the methods in the London Stock Exchange or the LSE are: offer for subscription, an open issue and a stock exchange opening.The under pricing of IPO’s in the market refers to the extensive inspection that regardless of the scheme of entering into the market, the IPO’s be inclined to give considerable returns within days or weeks after the issue has been opened. Rilter (1985), Welch (1987), Ibotsen et al.(1995), Dimson (1979), Buckland et al. (1981), Jenkins and Meyer (1988) point toward the average first day gains at the UK main market which varies from 9 % to 17%. According to Levis and Thomas (1995), during the period from 1985 to 1992, the LSE market had an average first day gains of 1.87% for a total of 106 IPO’s that was issues during the period.

Vietnam War Overview

The Vietnam War occurred in present-day Vietnam, Southeast Asia. It represented a successful attempt on the part of the Democratic Republic of Vietnam (North Vietnam, DRV) and the National Front for the Liberation of Vietnam (Viet Cong) to unite and impose a communist system over the entire nation. Opposing the DRV was the Republic of Vietnam (South Vietnam, RVN), backed by the United States. The war in Vietnam occurred during the Cold War and is generally viewed as an indirect conflict between the United States and Soviet Union  with each nation and its allies supporting one side. Vietnam War Dates The most commonly used dates for the conflict are 1959-1975. This period begins with North Vietnams first guerilla attacks against the South and ends with the fall of Saigon. American ground forces were directly involved in the war between 1965 and 1973. Vietnam War Causes The Vietnam War first began in 1959, five years after the division of the country by the Geneva Accords. Vietnam had been divided into two, with a communist regime in the north under Ho Chi Minh and a democratic government in the south under Ngo Dinh Diem. In 1959, Ho commenced a guerilla campaign in South Vietnam, led by Viet Cong units, with the goal of reuniting the country under a communist government. These guerilla units often found support among the rural population who desired land reform.   Worried about the situation, the Kennedy Administration elected to increase aid to South Vietnam. As part of the larger goal of containing the spread of communism, the United States endeavored to train the Army of the Republic of Vietnam (ARVN) and supplied military advisors to aid in combating the guerrillas. Though the flow of aid increased, President John F. Kennedy did not wish to use ground forces in Vietnam as he believed their presence would cause adverse political consequences.   Americanization of the Vietnam War In August 1964, a US warship was attacked by North Vietnamese torpedo boats in the Gulf of Tonkin. Following this attack, Congress passed the Southeast Asia Resolution which allowed President Lyndon Johnson to conduct military operations in the region without a declaration of war. On March 2, 1965, US aircraft commenced bombing targets in Vietnam and the first troops arrived. Moving forward under Operations Rolling Thunder and Arc Light, American aircraft began systematic bombing strikes on North Vietnamese industrial sites, infrastructure, and air defenses. On the ground, US troops, commanded by General William Westmoreland, defeated Viet Cong and North Vietnamese forces around Chu Lai and in the Ia Drang Valley that year.   The Tet Offensive Following these defeats, the North Vietnamese elected to avoid fighting conventional battles and focused on engaging US troops in small unit actions in the sweltering jungles of South Vietnam. As fighting continued, leaders Hanoi contentiously debated how to move forward as American air strikes were beginning to severely damage their economy. Deciding to resume more conventional operations, planning began for a large-scale operation. In January 1968, the North Vietnamese and the Viet Cong commenced the massive Tet Offensive. Opening with an assault on US Marines at Khe Sanh, the offensive featured attacks by the Viet Cong on cities throughout South Vietnam. Combat exploded throughout the country and saw ARVN forces hold their ground. Over the next two months, American and ARVN troops  were able to turn back the Viet Cong assault, with particularly heavy fighting in the cities of Hue and Saigon. Though the North Vietnamese were beaten with heavy casualties, Tet shook the confidence of the American people and media who had thought the war was going well. Vietnamization As a result of Tet, President Lyndon Johnson chose not to run for reelection and was succeeded by Richard Nixon. Nixons plan for ending US participation in the war was to build up the ARVN so that they could fight the war themselves. As this process of â€Å"Vietnamization† began, US troops started to return home. The mistrust of Washington that had begun after Tet increased with the release of news about bloody battles of questionable value such as Hamburger Hill (1969). Protests against the war and US policy in Southeast Asia further intensified with events such as soldiers massacring civilians at My Lai (1969), the invasion of Cambodia (1970), and the leaking of the Pentagon Papers (1971).   End of the War and the Fall of Saigon The withdrawal of US troops continued and more responsibility was passed to the ARVN, which continued to prove ineffective in combat, often relying on American support to stave off defeat. On January 27, 1974, a peace accord was signed in Paris ending the conflict. By March of that year, American combat troops had left the country. After a brief period of peace, North Vietnam recommenced hostilities in late 1974. Pushing through ARVN forces with ease, they captured the Saigon on April 30, 1975, forcing South Vietnam’s surrender and reuniting the country.   Casualties United States: 58,119 killed, 153,303 wounded, 1,948 missing in action South Vietnam 230,000 killed and 1,169,763 wounded (estimated) North Vietnam 1,100,000 killed in action (estimated) and an unknown number of wounded Key Figures Ho Chi Minh – Communist leader of North Vietnam until his death in 1969.Vo Nguyen Giap – North Vietnamese general who planned the Tet and Easter Offensives.General William Westmoreland – Commander of US forces in Vietnam, 1964-1968.General Creighton Abrams – Commander of US forces in Vietnam, 1968-1973.