Organizations and group behavior Essay Example | Topics and Well Written Essays - 2000 words

Organizations and group behavior - Essay Example In accordance with the issues discussed in the paper the increase of competition in all industries has led organizations to search for strategies, which can help them to develop a competitive advantage towards their rivals. In order to identify the key elements of group behavior it should be necessary to understand primarily the characteristics of a group, as part of the organizational life. In accordance with Martin within organizations, different forms of group can be identified: a) individuals working on similar organizational activities may not constitute a group; for example, the lecture staff in the same department of a particular university may not meet or cooperate; these individuals cannot be characterized as a group, b) the sub-sections of certain organizational departments are often parts of formal organizational units and they are likely to help towards the completion of organizational tasks of low importance, c) informal groups within organizations are common for promoti ng specific organizational tasks or ideas; for instance, the case of ‘friendship groupings and task-depended networks’, d) groups related to a particular organizational project can be developed within an organization; these groups, formal or informal, are not permanent, as for example ‘a project group working on the building of a new oil refinery’, e) formal and informal groups can be developed within organizations for completed a particular organizational task; these groups are ‘transient’, as for example a formal group working on the reduction of the organization’s travel expenses by 10%.... within an organization; these groups, formal or informal, are not permanent (Martin 232), as for example ‘a project group working on the building of a new oil refinery’ (Martin 232), e) formal and informal groups can be developed within organizations for completed a particular organizational task; these groups are ‘transient’ (Martin 232), as for example a formal group working on the reduction of the organization’s travel expenses by 10% (Martin 232). The development of group activities within modern organizations has been often related to the trend of firms to imitate the strategies of their rivals (Griffin and Moorhead 2011). In the study of Griffin and Moorhead (2011) reference is made to the risks that such strategy can hide mostly because of the following fact: the use of teams for promoting organizational plans can be beneficial for organizations but the costs involved can be also significant. The case of Ampex is mentioned as an example of the benefits of team development within modern organization: in Ampex, the involvement of teams in organizational activities led to the increase of ‘online customer delivery by 98%) (Griffin and Moorhead 272). In Texas Instruments, the use of teams for developing the daily organizational tasks resulted to the reduction of organizational costs for about 50% (Griffin and Moorhead 272). Also, in Eastman, the development of teams across the organization supported the increase of organizational performance at significant levels; the productivity of the organization was increased for about 70%, a result which was directly related to the involvement of teams in all organizational projects (Griffin and Moorhead 272). In accordance with the above findings, the role of group in the development of organizational performance,

Vaccines Essay Example | Topics and Well Written Essays - 750 words

Vaccines - Essay Example Vaccines stimulate the immune system of the body and helps it recognize the agent as a pathogen or foreign, hence destroying it (Bona and Bonilla, 1996). Vaccines do not offer complete protection of the body against a certain disease; therefore, it is important to choose the most adequate type of vaccine in order to make it more responsive. To develop an effective immune against a dangerous virus, one must consider important aspects, which include the rate of maintaining high immunizations even when the disease is rare. Other factors to be considered include the impact of the immunization campaign on the epidemiology of the disease in the long term and the continuous surveillance of the disease due to the introduction of the new vaccine. An inactivated whole organism vaccine is produced by the killing or destruction of a disease causing organism by use of radiation, heat or chemicals (Reiss, 2005). It has several advantages since it is very stable and safe, which is an advantage over live vaccines, since the inactivated vaccines are killed and cannot mutate back to form the disease causing agent. They are advantageous since they do not require refrigeration hence their storage and transportation is easy, which makes it accessible for people in developing countries. Inactivated vaccines also have the main disadvantage of triggering a weak immune system response; hence several boosters are needed where as live vaccines stimulate a stronger one. This is a major set back to people in areas that are inaccessible to healthcare due to lack of boosters. Another set back is that the nonantigenic portions of the vaccines microbe may cause an inflammatory response to some people. Attenuated whole organism vaccines are live vaccines that contain the living microbe or the modified live viruses which are only weakened in laboratories in order to prevent diseases (Goldsby et al 2000). Viruses are attenuated by growth of generations in cells where they do not reproduce so well , the unsuitable environment makes them repel the viruses. As they grow they become weak due to the new environment and their natural host. They are the closest thing to natural infections hence they are good to the immune system. They stimulate strong antibody and cellular responses, and give lifelong protection with one or two doses. They are easy to create for given diseases like chickenpox. There are several setbacks to this immune system, for example the attenuated vaccines are live so they may revert and cause disease, and people with weakened immune systems for example HIV-positive people cannot use attenuated vaccines for their own protection. Attenuated vaccines need to be refrigerated therefore it is hard to store and transport them to under developed areas. They are difficult to create for bacteria, since bacteria have so many genes, therefore, it is hard to control them. Recombinant vector vaccines are also known as sub-unit vaccines, and are comprised of antigens which elicit the immune system best combined with the DNA of another (Murphy, Walport and Travers, 2008). They are mainly used for complex infections, are experimental and are similar to DNA vaccines though they use bacteria to bring out DNA to the cells in the body. Vector means the virus or a bacterium that is used as the carrier virus latches on to the cell and injects genetic material into the cell. Scientists take the genomes of harmless viruses and insert the genetic material in portions into the cells. The viruses ferry the microbial DNA to the cells. The recombinant vector vaccines cause a natural infection and, therefore, stimulate the immune system. Attenuated bacteria also play the role of vectors, where the genetic mater

Conscious and subconscious information processing Essay

Conscious and subconscious information processing - Essay Example Many analogies have been made to describe the conscious mind. One effective metaphor might be the telescope. Our conscious mind looks through it and sees a particular object in focus, unaware of the world outside of that telescope lens. Thus consciousness is limited to a small radius, although it serves its purpose. Another metaphor for the conscious mind would be an iceberg. The conscious mind is the tip of the iceberg that extends out of the ocean. The conscious mind perceives the world from information derived from the subconscious below, and from the physical world around it. Subconsciousness literally means beneath the threshold of consciousness, or that part of the mind that lies just below the level of conscious thinking. In the example of the telescope, while the conscious mind is looking through the small opening, the subconscious is recording the impressions while also searching memory banks for corroborating information. The subconscious mind acts as a personal secretary who records conscious data and who also retrieves relevant memories from the unconscious mind. It behaves like the RAM (random access memory) in a computer. It filters and retains information for the purpose of directing it to its necessary applications. A very active subconscious mind detects patterns to predetermine conscious thinking and behavior. For example, when we are first learning how to drive a car, our conscious awareness must be extremely focused in order to learn the skill. Once we have learned how to drive, the conscious mind goes on autopilot, and the subconscious t akes over, doing the driving for us. The way the subconscious operates is far different from the way conscious mind works. While the conscious mind is objective, relying on logic and literal thinking, the subconscious is subjective, processing the subliminal and symbolic meaning of words and imagery. Thus it is the subconscious mind that retains feelings and images from

Anthropology Essay Example | Topics and Well Written Essays - 1500 words - 2

Anthropology - Essay Example The people of the Samoan Islands share a common language – Samoan, a common culture – fa’a Samoa and an indigenous form of governance called fa’amatai.2 â€Å"Due to colonialism, the Samoa Islands and people were divided by Western powers. Today, politically the islands have two jurisdictions, the independent country of Samoa at the western half of the islands, and the territory of American Samoa comprising the islands to the east. The two regions are separated by 64km of ocean. Most Samoans are full-blooded and comprise one of the largest Polynesian populations in the world.3 Fa’a Samoa means the Samoan Way.4 Fa’a Samoa dictates how Samoans should conduct themselves. This brings out the Samoan Identity and how they should fulfill their obligations towards their families, their communities, the Church and their fellow Samoans. At the heart of the Samoan Identity is Respect, an unquestioning respect for their established institutions, their systems and their elders. Religion is a very important part of the Samoan Culture. Samoa’s motto in fact is based on religion – â€Å"Samoa is founded on God†5 Originally Samoans had a polytheistic religion. This belief is divided in to two – the Atua (non-human) and Aitu gods (human) which also include ancestor worship.6 Thus, when religious expeditions arrived in Samoa, assimilation of the new world was not met by too much resistance. Today, the main religions in Samoa include Congregational, Catholic, Methodist, Assembly of God, Seventh Day Adventist, Bahai,, the Latter Day Saints and Jehovah’s Witnesses.8 Paganism was replaced by the promise of eternal life of these new religions. But what remains is that religion plays a central part in the lives of Samoans. In Samoa, the aiga (extended family) is all important.9 Villages are composed of aiga’s and the greater

Web 2.0 Applications Essay Example for Free

Web 2.0 Applications Essay O’Reilly (2006) in his Commencement Speech at UC Berkley , explained that the genuine Web 2. 0 application is the one where there is a proportionality between the number of users and the development of the application. Because of this, it is argued that the core value of Web 2. 0 is being able to effectively harness the innovativeness of everyone in the group. This kind of development is a step forward as compared to the previous state of the internet where the Web as a platform remained a baffling mess of buzzwords with no real clarity. Spolsky(2005) agreed with this stating that Web 2.0 is â€Å"a big, vague, nebulous cloud of pure architectural nothingness† and that â€Å"when people use the term Web 2. 0, I always feel a little bit stupider for the rest of the day. † Although this is obviously true, in this specific sense, the concept of the Web 2. 0 application is nothing new at all to the World Wide Web. The term Web 2. 0 is used when a read-write aspect of the Web is used in a participatory way that actually creates greater shared knowledge for all. It was the widespread adoption of blogs, wikis, MySpace and other read-write techniques that ushered in a common I-write-and-everyone-reads-it usage pattern (Hinchcliffe 2006). The concept of Weblog or Blogging has been defined by Drezner and Farrell (2004) as â€Å"A web page with minimal to no external editing, providing on-line commentary, periodically updated and presented in reverse chronological order, with hyperlinks to other online sources. † Yet even though this definition exists, other researchers such as Nardi et al (2004) express that weblogs currently accessible in the internet have a great diversity that is there is not a single dominant style of activity in the net. Others (Dyrud , Worley Quible, 2005) agree with this but on the hand, they expressed that there is something common to all blogs and that is they are primarily a venue in order to share information (regardless of the amount and manner) between people, groups, and organizations. According to Blood (2000) there are essentially two types of weblog: those that emphasize the diary and comment aspect, and those that emphasize hyperlinks. The former may seek to influence wider public opinion, or merely to raise the profile of the blogger; the latter act as a filter system, looking at what exists on the Web and recommending content that might be of interest to visitors. If bloggers make mistakes in the information they publish, they rely on their peers to point out any errors (Johnson and Kaye 2004) – this sentence is very ‘stand alone’ you may wish to introduce the idea of authority of authority of Web 2. 0 technologies (which will presumably covered again in Wikis etc) . Thus, Blogs have unique features that traditional web media does not have. About 2. 7 million bloggers update their blogs at least weekly. According to Technorati, new blog creation continues to grow Figure X shows the number of new blogs created each day, from January 2004 to January 2006: As was mentioned above, there are various types of blogs and each variation provides the information to the user as different as possible. Factors to be considered are the type of the media to be used in order to transfer the information, the device that is used, the genre, the legal status of the publishers, blog search engines, and blogging communities and directories. One varying consideration to blogs is the kind of media that is used in order to share the message from the person/organization that would want to give the message to the recipient of the message. Take for example; a video blog is called a vlog, a blog that is comprised of links to other sites or networks is called a linklog. Another kind of blog that contains a series of sets of sketches is called a sketchblog and another type similar to a sketchblog is called a photoblog – one that comprises of photos being shared, uploaded and downloaded.

Great Gatsby Research Essay Essay Example for Free

Great Gatsby Research Essay Essay The majority of what Fitzgerald writes in his stories are about the love for rich girls. In real life he has personally experienced falling for a wealthy girl, Zelda. In the book, The Great Gatsby, he writes about a boy who isn’t rich that is in love with a girl named daisy, who is rich like Zelda. Gatsby later lost his love, Daisy, when he went to war, for Fitzgerald, he was rejected by Ginevra King’s father who said â€Å"poor boys don’t marry wealthy girls,† which was said by Daisy in the book. He was asking for her hand in marriage. Then Fitzgerald got denied by Zelda Sayre. Daisy, the women jay Gatsby has been basing on his whole life on, is similar to Zelda Sayre who would not marry him at first since he was unsuccessful Fitzgerald lived in Great Neck, Long Island, in which his first child was born. To Zelda, Fitzgerald was seen poor but he was really upper middle class, but Zelda’s Standards were too high, like Daisy. Gatsby and Fitzgerald both met vital women to their lives at dances and both while they were stationed at army camps They both had highly society connections and down falls such as Gatsby getting murdered in the pool by George Wilson, for love. Fitzgerald died of alcohol use when he was trying to become rich again. Gatsby made money by bootlegging while Fitzgerald made money by writing. Fitzgerald Scott was self-destructive because he would drink to much, due to being an alcoholic. He was very social but then later on in his life he became very rude and started to offend people, due to his alcoholism. Gatsby was always trying to make himself better, improving him self. He was very self-disciplined and an outsider. They were both faithful and dedicated to the ladies the fell in love with. F. Scott’s wife, Zelda, was sent to a refuge in the last few years of her life. He made sure to never allow him or their daughter that they had together for get about her. Being the dedicated man he was, he would go see her to visit at the asylum. In the book, many of the characters represents the people that Fitzgerald met in his life, including his own character that represents him. To add on to that, F. Scott Fitzgerald lived in Great Neck, Long Island after his first child was born. At the time, the Great Neck was home to many of the wealthiest people on Long Island. A scholar has proven that there are many similarities between the Great Neck and the West Egg. In the movie version, Daisy tells Gatsby that Rich girls dont marry poor boys. This line was taken straight out of Fitzgeralds life. The father of his first love, a young woman by the name of Ginevra King, supposedly told him that after Fitzgerald asked for Ginevras hand in marriage. There are many other similarities between F. Scott Fitzgerald and Jay Gatz (Gatsby)- keep your eyes out for them! F. Scott and Gatsby were born in a middle class family. Both of their fathers started out very wealthy until they both failed with their business when the crashed. They both came from an underprivileged family, in many cases, inclined a lot on both of their behaviors and goals. For school, both Gatsby and F. Scott were drop-outs from Universities and joined the army in 1917. There are a bunch of similarities between the two. The Author of the Great Gatsby, Fitzgerald Scott, based this story one his own life in almost every scene in the book.

Cutaneous Tuberculosis Disease: Challenges of Treatment

Cutaneous Tuberculosis Disease: Challenges of Treatment CHAPTER -1 CUTANEOUS TUBERCULOSIS INTRODUCTION: In this innovative world while progress in medicine has helped up to deal with many diseases Tuberculosis and Cutaneous Tuberculosis is still a challenge for doctors. A resurgence of Cutaneous Tuberculosis in areas of high HIV incidence, drug resistant present in patients with pulmonary tuberculosis and in immunosupressed patients are the main challenges for clinicians. (6) Cutaneous TB is caused by Mycobacterium tuberculosis, Mycobacterium bovis, Bacillus Calmette-Guerin (BCG) vaccinations and the Tuberculids whose pathogenesis is poorly understood. Cutaneous TB is very variable in its clinical presentation, significance prognosis. Factors which effect on variability are: The pathogenesity of the organism involved. The Previous treatment given. The Immune status of the patients which can be related to the presence of Acquired Immunodeficiency Syndrome (AIDS) or Immunosuppressive therapy. The Port of infection. Any Local factors like, the recent Trauma, the lymphatic drainage, the vascularity of area and the proximity to lymph nodes). PREVALANCE: Thirty years ago it was assumed world wide that tuberculosis would be eradicated in the developed countries, as its incidence increased only on by average 6 % in the United States and 10% in Europe between the years 1953 and 1985. However, in 1983 tuberculosis was declared a global emergency by the world Health Organization because of a sharp increase in incidence. (9) Among infectious diseases, Tuberculosis is an important cause of death. Tuberculosis was responsible for 6% of deaths worldwide. Global prevalence of TB currently is greater than 32%. More than 50% of new patient occurrences were in 5 Asian countries, i.e. India (largest worldwide patient load), China, Indonesia, Bangladesh, and Pakistan(ref ?) The current global burden of Tuberculosis is mind boggling. In 1997, the incidence of new Tuberculosis patients approached 8 million in addition to more than 16 million patients already diagnosed. Around 2 million people died of Tuberculosis in 1997 with a global fatality rate of 23%, fatality rates exceed 50% in some African countries in which there is a high HIV incidence. Approximately 8% of tuberculosis patients are HIV infected. (2) Prevalence of tuberculosis infection in 1985, 1995 and 2005 (10) Prevalence of tuberculosis has increased between 1985 and 2005.According to the World Health Organization case reports statistics, in 1985 there were around 3 million patients of tuberculosis of all types with the highest no of cases in Asia and Africa. In Asia the highest numbers of cases were in India, Pakistan, China, Philippines, Bangladesh, Afghanistan and Vietnam. In Africa the highest number of case were in Ethiopia, Nigeria, South Africa, Congo, Morocco and Tanzania. (10) During the last two decades the number of cases increased all over the world. In 1995 the total number of cases increased to 4.6 million and in 2005 to 7.5 million worldwide. In Asia in 2005 the highest numbers of cases were in India, China Pakistan. In Africa in 2005 the highest numbers of cases were in South Africa, Ethiopia Congo. (10) There is an increasing rate of tuberculosis in the developing countries is approximately 500/100,000/y. Great alarm has been the progressive increase in numbers of strains of tuberculosis that are resistant to antibiotics. Since 1984, that incidence of extra pulmonary tuberculosis has increased at even faster rate than that of pulmonary tuberculosis and is considered to be a diagnostic criterion in the case definition for AIDS. Because immunocompromised individual are at increased risk of extra pulmonary tuberculosis, so dermatologist are renewing their historic role in the diagnosis of cutaneous lesions of tuberculosis. (11) EPIDEMIOLOGY: Epidemiological analysis is used to detect the changing trends in the incidence and prevalence of mycobacterial disease in the community. The main objectives of these methods are to determine the natural behavior of disease and factors which affect his behavior and to calculate future trend if possible to help in the design of any control measures and to assess the usefulness of these measure.(8) Even though 1 of 3 individuals on this planet is infected with tubercle bacillus, the incidence of Cutaneous TB appears low. In areas such as India or China where TB prevalence is high, cutaneous manifestations of TB (overt infection or Tuberculids) are found in less than 0.1% of persons seen in dermatology clinics. The frequency of patients with Cutaneous Tuberculosis seen between 1980 and 1993 in a hospital dermatology clinic in Madrid was 16 per 10,304 which was 0.14%. In a ten year retrospective survey of patients seen in governmental dermatology clinics in Hong Kong between 1983 and 1992, the detected incidence of Cutaneous Tuberculosis among patients was 179 per 267,089 which was 0.07%. Among patients with Cutaneous Tuberculosis only15% had classic Cutaneous Tuberculosis and 85% had tuberculids. In that classical cutaneous tuberculosis approximately 5% had lupus vulgaris, 5% had Tuberculosis Verrucosa cutis and 5% had scrofuloderma. (2) In a tertiary-care hospital in northern India, 0.1% of dermatology patients seen between 1975 and 1995 had Cutaneous Tuberculosis. Lupus vulgaris was the most common manifestation around 55%, followed by scrofuloderma 27%, TB Verrucosa cutis 6%, tuberculous gumma 5%, and tuberculids occurred in 7%. (2) FREQUENCY: USA: In the United States, tuberculosis cases decreased from 84,304 cases in 1953, when national reporting was first began, to 22,201 in 1985.   This represented fairly steady decline of about 5.8% per year. However, the turn down in tuberculosis cases stopped in between 1985 and 1992. In 1992 the annual number of cases increased by 20% to 26,673 cases. (12) The increases were concentrated geographically in several states, with over 90% of the 14,871 cases in California, Florida, New Jersey, New York, and Texas and demographically tuberculosis occurred in racial and ethnic minorities, in people aged 25 to 44, males and in those born abroad. Especially troubling, and indicative of increasing transmission of new infections, was a 36% increase in tuberculosis among children 4 years old or younger. Tuberculosis appears to be on the decline again in the United States as numbers with only 14,871 cases in 2003. (12) Reported tuberculosis cases in United States, 1982-2002 (12) The percentage of Tuberculosis patients who were born abroad individuals was 42%. People born in Mexico, the Philippines, and Vietnam account for one half of born abroad Tuberculosis patients in the United States. The Tuberculosis rate among born abroad people was 4 to 6 times higher than for US-born peoples. Minimum estimates of the proportion of TB patients with coincident HIV infection were approximately 10-15%. Among people aged 25-44 years, this proportion increased to 20-30%. (12) The fundamental origin of this new Tuberculosis epidemic in troubled states reflects a minimum of four major factors including (1) the involvement of Tuberculosis with the HIV epidemic, (2) the increased migration from countries where Tuberculosis is common, (3) the spread of Tuberculosis in congested settings (health-care facilities, prisons, homeless shelters), and (4) the worsening of the basic health-care infrastructure. (2) Molecular typing of Mycobacterium tuberculosis isolates in the United States in a restriction fragment-length polymorphism study suggests more than one third of new patient incidence results from people-to-people transmission, and the remainder result from reactivation of latent infection. Approximately 1 of 13 Mycobacterium tuberculosis isolates currently shows a form of drug resistance. (2) The modern introduction of biological agents that block tumor necrosis factor-alpha in the treatment of rheumatoid arthritis, psoriasis, and several other autoimmune disorders has additional raised about the necessity of the identification of patients with latent Tuberculosis. At present, several hundred cases of Tuberculosis have been reported in patients who receive these tumor necrosis factor-alpha antagonists. (2) HISTORY: Tuberculosis has an ancestry which can be traced to the earliest history of mankind. It was recognized as a contagious disease by the time of Hippocrates and Aristotle in 350 BC. Signs of skeletal Tuberculosis were identified in Europe since Neolithic times and in ancient Egypt around 3700 BC in mummified bodies. Evidence of TB appears in Biblical scripture, in Chinese literature dating back to around 4000 BC, and in religious books in India around 2000 BC. (5) During1600s and 1800s tuberculosis was known ass the Great White Plague in Europe.   Other names for Tuberculosis were Phthisis which was from Greek term phthinein, meaning to waste away, scrofula which were used for swellings of the lymph nodes of the neck and consumption which were used as progressive wasting away of the body.(2) In 1826 Laennec first reported cutaneous tuberculosis which he called PROSECTOR WART. Following Laennec, Rokitansky and Virchow described the histological features in detail comparing them to those of visceral tuberculosis. (6) The Incidence of TB increased with population density and urban development so that by the Industrial Revolution in Europe in 1750, it was responsible for more than 25% of adult deaths. Indeed, in the early 20th century, TB was the leading cause of death in the United States. In 1882, a German biologist ROBERT KOCH presented his discovery of the organism that caused TB. NEIL FINSEN won the Nobel Prize in Medicine in 1903 for introducing UV light into the treatment of skin TB. (2) With the help of better living conditions and the introduction of the antibiotic streptomycin on 20th November 1944, the number of reported TB patients in the United States steadily declined around 126,000 TB patients in 1944, 84,000 in 1953, 22,000 in 1984, and 14,000 in 2004.(2) MODE OF TRANSMISSION: Tuberculosis is an airborne contagious disease that occurs after inhalation of infectious droplets expelled from patients with laryngeal or pulmonary Tuberculosis during coughing, sneezing, or speaking. Each cough can generate more than 3000 infectious droplets. Droplets are so small around 1 to 5 micro meter, that they remain airborne for hours. (2) The likelihood that disease transmission will occur depends upon the infectiousness of the tuberculous patient, the environment in which exposure takes place, and the duration of exposure. Roughly 20% of people in the infected household contact develop infection. Micro epidemics have occurred in closed environments such as transcontinental flights and submarines. Tuberculin sensitivity develops 2 to 10 weeks after infection and usually is lifetime. (2) Because Tuberculosis induces a powerful immune response, individuals with positive tuberculin reactions are at a considerably lower risk of acquiring new tuberculous infection. In HIV-infected individuals, active Tuberculosis is more likely to occur from reactivation of existing disease than from superinfection with a new mycobacterial strain. (2) Without treatment, an estimated 10% lifetimes possibility exists of developing active disease after tuberculous infection, 5% occurs within the first 2 years and 5% thereafter. An Increased risk of acquiring active disease occurs during HIV infection, Intravenous drug abuse, diabetes mellitus, silicosis, immunosuppressive therapy, cancer of the head and neck, hematological malignancies, end-stage renal disease, intestinal bypass surgery or gastrectomy, chronic malabsorption syndromes and low body weight. Infants younger than two years are associated with increased risk. (2) 1) DIRECT INHALATION: The most common mode of entry via portal in to the lungs usually resulting from the Inhalation of airborne droplets containing a few bacilli, expectorated by individuals with â€Å"open† pulmonary disease.(8) 2) INDIRECT INHALATION: A) Ingestion: Less often bacilli may be swallowed and lodge in to the tonsil or in the wall of the intestine. These infections are chiefly related to the consumption of contaminated milk products. (8) 3) INOCULATION: Cutaneous tuberculosis manifestations depend upon the method of cutaneous inoculations, which may be exogenous that is from an out side source, may occur by autoinoculation, or may be by endogenous .Direct exogenous inoculation in an individual not previously infected with tuberculosis causes primary tuberculosis infection, will led to the tuberculous ‘chancre or to tuberculosis Verrucosa cutis depending upon the immune status of the patient. Another example of exogenous transmission is lupus vulgaris at the site of BCG vaccination. (9) Endogenous transmission can occur by continuous extension of tuberculous process underlying the skin as in scrofuloderma, by the way of lymphatic as in lupus vulgaris and by hematogenous spread as in acute miliary tuberculosis or lupus vulgaris. (9) Infrequent mode of transmission is direct implantation in to the skin through cuts and abrasions. These troubles usually in persons, working with infected material or cultures of tubercle bacilli. These skin lesions were called as â€Å"Prosector warts† (8) CLASSIFFICATION OF CUTANEOUS TUBERCUCLOSIS: Cutaneous tuberculosis clinical manifestations comprise a considerable number of skin changes, usually sub classified in to more or less distinct disease forms. Classification depends on morphology more recently mode of transmission or the immunological state of host, but none of them satisfies completely. 1)INOCCULATION TUBERCUCLOSIS (Exogenous Source) Tuberculosis chancre Warty tuberculosis(Verruca cutis) Lupus vulgaris(some) 2) SECONDARY TUBERCULOSIS (Endogenous source) A) Contiguous spread Scrofuloderma B) Auto-inoculation Orifical tuberculosis 3)HAEMATOGENOUS TUBERCULOSIS Acute miliary tuberculosis Lupus vulgaris(some) Tuberculous gumma 4)ERUPTIVE TUBERCUCLOSIS (Tuberculids) A) Micropapular Lichen scrofulosorum B) Papular Papular/Papulonecrrotic TB C) Nodular Erythema induratum(Bazin) Nodular Tuberculids (CLASSIFICATION OF TUBERCULOSIS, MODIFIED FROM beyt et al) (4) CHAPTER-2 CLASSIFICATION OF MYCOBACTERIA: Tuberculosis is an infectious disease which is caused by the Mycobacterium species. Mycobacteria are acid fast, non-sporulating, non-motile weakly gram positive organisms. TEM micrograph of Mycobacterium tuberculosis Table 3: Kingdom Bacteria Phylum Actinobacteria Order Actinomycetales Suborder Corynebacterineae Family Mycobacteriaceae Genus Mycobacterium Scientific classification by Lehmann Neumann. (3) In 1950s Runyon classified the atypical mycobacteria according to their ability to form pigment, their rate of growth colony characteristics. This classification also includes obligate human pathogens and facultative human pathogens. (1) Today more then 60 species of mycobacteria are identified. Around 41 of these were included in the approved lists of bacterial names in 1980. (9) 30 species of mycobacterium are known that can cause disease in humans. The most common causative organism includes: Mycobacterium tuberculosis Mycobacterium Leprae. Atypical mycobacteria. The species which produce disease in tuberculosis primary complex include: Mycobacterium tuberculosis. Mycobacterium Bovis. Mycobacterium Africanum. Sometimes Bacillus Calmette Guerin (BCG) may also cause disease. (1) MEDICAL CLASSIFICATION: For the purpose of diagnosis treatment mycobacteria can be classified in several major groups. Mycobacterium tuberculosis complex, which can cause tuberculosis by the pathogens Mycobacterium tuberculosis, M Bovis, M Africanum M microti. Mycobacterium Leprae, which causes Hansens disease. Nontuberculous mycobacteria are the mycobacteria which can cause pulmonary disease, lymphadenitis, and skin disease disseminated disease. SLOW GROWING MYCOBACTERIA RUNYON GROUP 1)Obligate human pathogens M. tuberculosis-bovis group including bacillus Calmette-Guerin(BCG) M Africanum (not included in runyon classification 2)Facultative Human pathogens M. kansasii I M. marinum I M. simiae I M. scrofulaceum II M. szulgai II M. gordanae II M. avium-intracellualr complex III M. haemophilum III M. Ulcerans III M. xenopi III 3) Nonpathogens M. flavescen II M. terrae complex III M. trivale III M. gastri III RAPIDLY GROWING MYCOBACTERIA 1))Facultative Human pathogens M. fortuitum I V M. chelonae I V M. abscessus I V 2) Nonpathogens M. smegmatis I V M. phlei I V M. vaccae I V others STAINING CHARACTERISTICS OF MYCOBACTERIA: Mycobacteria are aerobic, facultative, intracellular non-spore forming and non-motile curved rods measuring 0.2- 0.5 by 2-4 um. Mycolic acid rich long chain glycol lipids and phospholipoglycans, a mycocides present in the cell wall of mycobacteria protect them. (2) Mycobacteria do not gram stain readily but their most valuable staining characteristic is Acid Fastness. This ability retains carbol fuchin dye after washing with acid or alcohol occurs because of the high content of cell wall mycolic acids, fatty acids other lipids. Other staining methods used include Dietrele, auramine-Rhodamine and phenolic acridine orange stains. Nocardia rhodococcus, legionella dadei, isospora cryptosporidium also share acid fastness. (1) The Ziehl-Neelson acid-fast stain, while highly specific for mycobacteria, is relatively insensitive, and recognition requires at least 10,000 bacilli per mL; most clinical laboratories currently use a more sensitive auramine-rhodamine fluorescent stain (auramine O). Routine culture uses a nonselective egg medium called Lowenstein-Jensen or Middlebrook 7H10 and often requires more than 3-4 weeks to grow because of the 22-hour doubling time of mycobacterium tuberculosis. Radiometric broth culture, BACTEC radiometric system of clinical specimens significantly reduces time 10 to 14 d for mycobacterial recovery. DNA probes specific for mycobacterial ribosomal RNA categorize species of clinically significant isolates after recovery. In tissue, polymerase chain reaction (PCR) amplification techniques can be used to detect Mycobactereria tuberculosis-specific DNA sequences and thus, small numbers of mycobacteria in clinical specimens. (2) The cell wall of mycobacteria consist of: (3) Outer lipids Mycolic acid Polysaccharides(arabinoglactan) Peptideglycan Plasma membrane. Lipoarrabinomannan(LAM) Phosphatidylinositol mannoside. Cell wall skeleton. PATHOGENESIS: The most common site for Tuberculosis disease is lungs and 85% of TB patients present with pulmonary symptoms. The most common sites of extrapulmonary disease are mediastinal, retroperitoneal, and cervical lymph nodes, vertebral bodes, adrenals, meninges, and the GI tract. Pathology of these lesions is similar to those in the lung. Extrapulmonary TB can occur as part of a primary or late generalized infection or as a reactivation site that may, coexist with pulmonary reactivation. (2) Mycobacterium tuberculosis is an obligate pathogen. It is a slender aerobic rod, characterized by high lipid content. This lipid is responsible for resistance to phagocytosis. Identification of organism is easy in tuberculous chancre, scrofuloderma, orificial lesions and the miliary variant. This may be difficult to find or absent in lupus vulgaris, gummata and warty tuberculosis. The organism is highly resistant to drying to drying and therefore can retain infectivity by inoculation or contamination of minor wounds. (19) The reaction of the bacterium depends on: the size of inoculum. the virulence of organism. <