...Cellular Structures and Pathogenicity Jennifer L. Wethington ITT Technical Institute Unit 2 Assignment 1 “Bacterial illness is a result of complex interactions between bacteria and the host. During evolution, humans developed many ways to protect themselves against bacterial pathogens. On the other hand, bacteria have developed strategies to evade, subvert or circumvent these defenses” (Sousa, 2003) “One of the most important characteristics of bacterial pathogenicity is the various strategies developed by prokaryotic organisms to use host molecules for their own benefit” (Sousa, 2003). “To accomplish this, bacteria have evolved elaborate control mechanisms to turn genes on and off, varying the transcriptional activator or protein repressors of systems that act at the structural level of the genetic material” (Sousa, 2003). “Without a doubt the most common and best studied of all prokaryotic motility structures is the bacterial flagellum. Composed of over 20 protein species with approximately another 30 proteins required for regulation and assembly, it is one of the most complex of all prokaryotic organelles” (Bardy, Ng, & Jarrell, 2003). “The bacterial flagellum is a rotary structure driven from a motor at the base, with the filament acting as a propeller. The flagellum consists of three major substructures: the filament, the hook and the basal body” (Bardy, Ng, & Jarrell, 2003). “One of the unusual variations on bacterial flagellation is the presence in...
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...Reproduction - Binary Fission rapid transverse cell division resulting to two equally sized daughter cells Habitat Ubiquitous Soil Water Air Living Organisms Pathogenicity Adhesion bacteria uses fimbriae to attach to surfaces ; sex pilus to attach to other bacteria Resistance increased by the type of cell wall, and presence of endospore, capsules, slime layers Toxin the lipopolysaccharide upper layer of Gram negative bacteria is released as toxins Taxonomy Domain : Bacteria Kingdom: Monera Phyla : Firmicutes Gram-Positive e.g. cocci Staphylococcus Streptococcus bacilli Lactobacillus Gracilicutes Gram-Negative e.g. cocci bacilli spirochete obligate intracellular parasites Tenericutes No Cell Wall e.g. Mycoplasma Ureaplasma Obligate Intracellular Parasite under phylum Gracilicutes 1. Rickettsia Pleomorphic Requires arthropod vectors ticks mites fleas Pathogenic Typhus Q Fever Trench Fever Rocky Mountain Spotted Fever 2. Bartonella Opportunistic Intracellular Parasite Vectors: Cat Flea Sandfly transmits Cat-Scratch Fever 3. Chlamydia Obligate Intracellular Coccoid Elementary Bodies small spore-like infectious particle released when infected cell ruptures Reticulate Bodies large intracellular inclusions containing replicating and growing form of chlamydia No Vectors Sexually transmitted : Chlamydia Infections: Urethritis Cervicitis PID Mycoplasma under phylum Tenericutes Lacks rigid cell wall Pleomorphic: can assume coccoid/bacillus...
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...According to Black, a prokaryotic cell is defined as lacking a nucleus and other membrane-enclosed structures. An example of a prokaryotic cell is a bacterium. “Most bacteria on this planet, both in the environment and living in and on humans, are member of the domain Bacteria.” There are many different structures within the bacteria cells, but the focus in this case will be on the ribosome. (Black, 2008) A bacillus, which is a rodlike bacterium, contains many different cell structures. It has a flagellum, which consists of fibrils and flagellin, a cell wall, that maintains the characteristic shape of the cell and prevents the bursting of the cell, and pili, that acts in an attachment or conjugation nature. The focus of this paper, the organelle ribosome, is made up of protein and RNA, and are spherical in shape. In most cases, especially with the bacteria, are clustered in polyribosome chains. To determine the size of a ribosome, one must measure how fast or slow they move toward the bottom of a tube in a centrifuge while it is being spun. This is know as the sedimentation rate of a ribosome. These sedimentation rates are measured in Svedberg units (S) and bacterial ribosomes measure at a rate of 70S, and their subunits somewhere between 30S and 50S. (Black, 2008) It is important to know that ribosomes present in prokaryotes are slightly different than those found in eukaryote. One difference is their size. This is important when treating the bacteria with antibiotics...
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...Pathogenicity and Cellular Structure Rebecca Abell Unit 2 Assignment 1 Pathogenicity and Cellular Structure When a human gets sick have you ever thought about how that occurs on a cellular level? Our body is made up with many different types of microorganisms and one of them is called bacteria. There are good bacteria and bad bacteria. When the bad bacterium multiplies with in the human body it causes what is known as bacterial infections. Although a bacterium is a microorganism it also has several cellular structures. The structures with in bacteria that cause us to become ill are Fimbriae, Plasmid, and the Capsule. Only the bacteria that contain these three structures can cause disease in a human body. When a bacterium includes the trouble causing structures the disease process starts spreading through the body. The reason that a disease process can not start without the three structures is because the bacteria has no protect for its self from the engulfing neutrophils or cells that destroy disease with in the human body. First the bacteria’s Fimbriae creates a thin structure in which allows the bacteria to attach to a host and not get swept away in the blood stream. Then the Capsule forms a slime layer so that the neutrophils are unable to engulf them thus destroying them. The Plasmid contains DNA and produces exotoxin which makes it resistant from other bacteria. These three structures are what help protect the bacteria and help it cause disease. Bacteria need...
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...Cellular Structures and Pathogenicity All the various surface components of a bacterial cell are important in the ecology because they mediate the contact of the bacterium possesses result from immediate contact with its environment. Its must use its surface components to assess the environment and respond in a way that supports its own existence and survival in that environment. The surface properties of a membrane and cell envelope, including capsules, glycocalyx, slayers, peptidoglycan and lps, and the other surface structures, such as flagella and pili or fimbriae. Bacterial surface components may have a primary biological function that has nothing to do with path ogenicity. However, there are endless examples wherein a bacterial surface component plays an indispensable role in the pathogenesis of infectious disease. Bacterial structures may act as permeability barriers that allow selective passage of nutrients and exclusion of harmful substances; adhesions used to attach or adhere to specific surfaces or tissues; enzymes to mediate specific reactions on the cell surface important in the survival of the organism; protective structures against phagocytic engulfment or killing; antigenic disguises to bypass activation oh host immune defenses; endotoxins, generally cell wall components, that cause an inflammatory response in the host; “sensing proteins” that can respond to temperature, osmolality, salinity, light, oxygen, genome of the cell that will cause expression of some...
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...catch malaria every year, and 200 million are infected with schistosomiasis. 39.5 million people are living with HIV/AIDS, with 4.3 million new HIV infections in 2006 (65% in sub-Saharan Africa). The eight Millennium Development Goals (MDG) hope to be achieved by 2015. These are: eradicating extreme poverty and hunger, universal primary education, gender equality and empowerment of women, reduction in child mortality,improvement in maternal health, combating HIV/AIDS,malaria and other diseases, ensuring environment sustainability and developing global partnership for development. DEFINITION INFECTION An infection is the entry and multiplication of an infections agent in the tissue of host. lf the infectious agent fails to cause injury to cells or tissue, then infection is asymptomatic. INFECTIOUS DISEASE An infectious disease is any change from a state of health in a part or all of the host body is not capable of carrying on its normal functions due to the presence of an organisms or its products. Infection and immunity involve interaction between...
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... 6. Describe 5 ways humans exploit microorganisms for their benefit. 7. What factors might cause some older diseases to show an increase in number of cases. UNIT 2 Prokaryotic and Eukaryotic Cell Biology 1. Describe the structure of the cell membrane and describe its components. 2. Explain the following terms with the use of diagrams: a) isotonic b) hypertonic c) hypotonic 3. Compare diffusion, facilitated diffusion, active transport and group translocation. UNIT 3 Main Groups of Microorganisms 1. Discuss reproduction of algae and fungi. 2. Describe how protozoa are classified. Give the name of member of each group and a disease caused by that organism. 3. Outline how viruses reproduce UNIT 4 Bacteria 1. Outline the process of endospore formation 2. Draw and label the structure of flagella found in gram negative organisms 3. State the various shapes and arrangements of bacilli and cocci also giving the respective planes of division. 4. How are structure and function related in the bacterial capsule? 5. How do mycoplasmas survive without a cell wall? 6. Could a mycoplasma infection be treated with penicillin? Explain. 7. Describe the structure of peptidoglycan. a) What are the functions of the cell wall to...
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...Microbiology Homework Assignment – Microbial/Bacteria/Viral Diseases Directions: Answer each question. Be sure to answer the ENTIRE question. See numbers in parentheses ( ) for point values. You must handwrite your answers in the space provided. In addition to answering the questions, you will be graded 5 points based on the neatness of your submitted work (including your handwriting). If I cannot read the answer, you will get 0 points for the question. If you use another source (website, journal article, etc.) to help you answer a question, you must cite it. 1. Name and describe the 3 types of symbiosis. (6) * Mutualism- a relationship between two species of organisms in which both benefit from the association. * Commensalism- a type of relationship between two species of a plant, animal, fungus, etc., in which one lives with, on, or in another without damage to either. * Parasitism- a relation between organisms in which one lives as a parasite on another. 2. Pick one of the types of symbiosis and find an example and describe it (using your textbook or the internet). (2) * Example of Commensalism: Remarkable cases occur of commensalism between certain crabs and sea-anemones, and they betoken much intelligence. 3. You want to prove that the Mycoplasma bacterium is the cause of tuberculosis. Describe how you would prove this using Koch’s postulates. (4) * The microorganism or other pathogen must be present in all cases of disease ...
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...Chapter 1 The Problem and Its Setting Introduction Thrombocytopenia or abnormally low platelet counts in the body are typically caused by genetic disorder or fatal diseases. This condition may result from thromboembolic or hemorrhagic complications caused by heparin as well as from various diseases states such as chronic liver disease and dengue hemorrhagic fever. In most rural areas a health care institution is often inaccessible and most patients cannot afford high cost medication. Henceforth, herbal medicines are often used as an alternative treatment. Inadequacy of providing supportive treatment to correct the decrease of platelet is fatal to patients. Thus, several decoctions of herbal plants are purportedly used to improve platelet count. Recently, the mortality rate in heparin – induced thrombocytopenia (HIT) has been reported as high as 20% (Greinacher & Lubanow, 2003). Retrospective data shows that up to 8% of heparinized patients will develop the antibody associated with HIT and that approximately 1–5% of patients on heparin will progress to develop HIT with thrombocytopenia suffering from venous and/or arterial thrombosis in at least one-third of cases (Warkentin et al., 1998). Heparin – induced thrombocytopenia (HIT) is a potentially devastating immune mediated adverse drug reaction caused by the emergence of antibodies that activate platelets in the presence of heparin. Despite thrombocytopenia, bleeding is rare; rather, HIT is strongly associated with...
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...Mycobacterium tuberculosis Cintia Jimenez-Mendoza Microbiology Summer I 2012 Taxonomy Scientific classification | Kingdom: | Bacteria | Phylum: | Actinobacteria | Class: | Actinobacteria | Order: | Actinomycetales | Suborder: | Corynebacterineae | Family: | Mycobacteriaceae | Genus: | Mycobacterium | Species: | M. tuberculosis | Binomial name | Mycobacterium tuberculosis | M. tuberculosis was discovered by Robert Koch in March 24 1882, who was a German physician and scientist. This specie is a pathogenic organism from the kingdom bacteria and genus Mycobacterium. This bacterium has caused most cases of tuberculosis which is an infectious disease caused by various strains of mycobacteria. Koch said once that the importance of this organism was huge due to the fact that M. tuberculosis is lethal to humans; he said "If the importance of a disease for mankind is measured by the number of fatalities it causes, then tuberculosis must be considered much more important than those most feared infectious diseases, plague, cholera..” [1] Fig.1.Taxonomy of Mycobacterium tuberculosis [2] The genus Mycobacterium includes pathogens that cause serious diseases like mentioned before tuberculosis and leprosy (Mycobacterium leprae). M. tuberculosis was also known as ‘tubercle bacillus’ or ‘Koch's bacillus’. . The Mycobacterium tuberculosis complex of organisms consists of other species like, Mycobacterium africanum which is mostly found in the West African...
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...1. The sudden unexpected occurrence of a disease in a given population: a. Outbreak b. Zoonotic c. Endemic d. Sporadic 2. A causative agent of peptic ulcer a. Escherichia coli b. Bordetella pertusis c. Shigella dysenteriae d. Helicobacter pylori 3. The “four o’clock habit” promoted by the Department of health is designed to prevent the spread of: a. Dengue fever b. Tuberculosis c. Malnutrition d.malaria 4. The first drug available for HIV: a. ZDU b. RMP c. TMP d. CMC 5. An immediate hypersensitivity reaction following exposure of a sensitized individual to the appropriate antigen: a. Hay fever b. Anaphylaxis c. Asthma d. Desensitation 6. A thin proteinaceous appendage necessary for bacterial conjugation: a. Cilium b. Trichome c. Flagellum d. Pilus 7. The use of nitrite as preservative for food is discouraged because: a. It can discolour the meat b. It can react with amines to form carcinogenic nitrosamines c. It decomposed to nitric acid which can react with heme pigments d. It is not readily available 8. The disinfectant of choice for municipal water supply: a. Lysol b. Chlorine c. Ozone d. Reverse osmosis 9. An object that is able to harbour and transmit microorganisms: a. Mite b. Fomite c. Arthropod d. Vector 10. Administration of a toxoid cenfers: a. Naturally acquired active immunity b. Naturally acquired passive immunity c. Artificially acquired active immunity d. Artificially...
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...INTRODUCTION Mung bean (Vigna radiata L. Wilczek) sprouts can be considered one of the most common vegetables consumed in the Philippines due to availability and nutritional value (Del Rosario, 2003 and FNRI, 1997). One cup of raw mung bean sprouts contains 48 calories, 6.5 grams of protein, 1.5 grams of fat, and 5.6 grams of carbohydrate. One cup of cooked bean sprouts contains 48 calories, 6.6 grams of protein, 1.8 grams of fat, and 4.6 grams of carbohydrate. In addition, sprouts are a good source of minerals and vitamins, particularly vitamins B1, B2, and C (http://ianrpubs.unl.edu/horticulture). Mung bean sprouts are low in calories and exceptionally high in potassium. A nutritious sprouted mung bean offers the same amount of vitamin A as a lemon, the niacin of a banana, the thiamine of an avocado, the riboflavin of a dried apple, the carbohydrate content of a melon and the ascorbic acid of a loganberry (http://www.specialtyproduce.com). The sprouting process encourages the rapid growth of microorganisms that reach very high numbers in the finished product (Fu et al., 2000). Seed sprouting provides an excellent environment for the growth of many types of organisms. The release of nutrients from the sprouting seeds, the moisture resulting from the irrigation process, the aerobic conditions, pH and temperatures favorable to mesophiles all contribute to the rapid expansion of microbial population, including food pathogens, during sprouting. Population as high as...
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...discussions * Informal * opens Friday 27th feb 5.00 Studies: How the body works Anatomy Gross anatomy – internal structures Microscopic anatomy- study of cells, study of tissues (microscope) Physiology- cellular physiology – e.g. nerves and muscle fibres Integrative physiology- different tissues and organs, functions e.g. cardiovascular Levels of organisation e.g. tissues, organs, organ systems organism levels Go through link called echo – access lecture recordings My unit- weekly feedback quiz Biology and chemistry lessons Textbook folder mastering a&p Lecture d 3rd week on a Tuesday Labour day (Monday) good Friday Assessments In class tests (30%) Quiz a (10 %) quiz b (20%) Worksheet questions (30%) Final exam 40% See unit outline for due dates, methods, extensions Quiz a Week 3 (early feedback) 30 mins to complete Opens 3pm Tuesday 10th Closes 3am Thursday 12th Quiz b Week 7 semesters Week 3 up to lecture 16 (muscles) 60 mins marked out of 50 Worksheet questions (30%) due week 11 of sem Set of questions provided online in week 8 Week 1-10 Final exam Mix mcq and sa Material from whole semester Higher weighting of 11 &12 Feedback about progress: Quizzes weekly Review assessments EIP BIOL 121 TUTORIAL 1 CHEMISTRY: Reading: pages 53-61 notes * Science of structure that deals with matter. * Defined as anything that takes up space and has mass. * Smallest units of matter...
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...Date……………………….. SUPERVISOR: DR. P.M WACHIRA Signature …………………… Date………………………. SCHOOL OF BIOLOGICAL SCIENCES. UNIVERSITY OF NAIROBI. 2011-2012 DECLARATION iii DEDICATION iv ACKNOWLEDGEMENT v ABSTRACT vi CHAPTER ONE 1 INTRODUCTION 1 1.1 JUSTIFICATION 2 1.2 OBJECTIVES 3 1.2.1 Broad objective 3 1.2.2 Specific objectives 4 CHAPTER TWO 4 LITERATURE REVIEW 4 2.1 Trichoderma Spp. 4 2.2 Fusarium species 8 CHAPTER THREE 11 MATERIALS AND METHODOLOGY. 11 3.1 Media Preparation 11 3.2 Isolation of pathogenic fungi (Fusarium spp). 12 3.4 Dual culture inoculation 13 CHAPTER FOUR 13 RESULTS 13 CHAPTER FIVE 18 DISCUSSION 18 CHAPTER SIX 20 CONCLUSION AND RECOMMENDATION 20 REFERENCES 21 8. Dudley, N. S. (2007). Pathogenicity of four Fusarium species on Acacia koa seedlings. Missoula, MT: U.S. Dept. of Agriculture, Forest Service, Northern Region, Forest Health Protection. 21 12. James, R. L. (2002). Biological control of Fusarium oxysporum and Fusarium proliferatum on young Douglas-fir seedlings by a nonpathogenic strain of Fusarium oxysporum. Missoula, MT: U.S. Dept. of Agriculture, Forest Service, Northern Region. 21 21. Ozbay, N. (2003). Biocontrol of Fusarium crown and root rot of fresh market tomato with Trichoderma harzianum strains under greenhouse conditions. New York: Biological Association. 22 DECLARATION I hereby declare that I am the sole author of this research paper. Every finding arrived at in this research paper is as a result of...
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...Rheumatoid Arthritis A Review of The Literature Mechanisms of Human Pathology Charles Childers Rheumatoid Arthritis Rheumatoid Arthritis (RA) is a chronic, autoimmune systemic inflammatory process that primarily attacks synovial joints as well as other tissues and organs of the body. This disorder is characterized by hyperplasia of synovial cells leading to an inflammatory response of the synovium that may ultimately cause destruction of articular cartilage. In cases of severe comprehensive damage joints can become ankylosed. RA is usually known to affect the wrist and hands bilaterally and symmetrically, but may be seen in any of the other synovial joints. The destruction can be progressive leading to joint deformations and disabilities.1 RA can also bring inflammation of the lungs, pleura, sclera of the eye, and pericardium. Nodules have been seen in the extensor tendons subcutaneously especially over the olecranon process. As has been reported,1 mechanistic paths to synovitis leading to this articular damage have shown tumor necrosis factor alpha (TNF-α) to take a significant part in joint inflammation responsible for the destruction. Therapies have developed to target TNF-α bringing a substantial impact on patient care. The exact etiology remains unclear in this autoimmune progressive disorder, but much is being looked at in search of an autoantigen or another triggering agent. According to Robinson,2 the importance of early diagnosis and...
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