Assignment 1
Gram stains are commonplace in many labs. It has many advantages including:
The gram stain assists medical professionals in identifying if bacteria are the cause of an infection and then it helps determine a course of treatment.
Treatment of Gram-negative bacteria results in the releases of the toxin Lipid A. The longer the delay in treatment results in more bacterial growth, the more bacterial growth the more toxins the patient will be subjected to. If enough toxins are released it could result in death. This is the primary reason that it’s important to quickly and accurately determine if infections are Gram-negative or Gram-positive.
Another benefit of the Gram stain is that it’s a relatively inexpensive way to allow the viewing of normally clear Bacteria with a typical light microscope having ample magnification ability.
The primary pitfall of the using the Gram-stain technique is human error. During this 4-step process, it’s easy to overheat during fixation, over wash or
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This work is usually done in the impoverished parts of the country where the disease is rampant. Common examples include HIV/AIDS, Yellow fever, Tuberculosis (TB), malaria, Hepatitis, Cutaneous Leishmaniasis and many more. The original complaints of night chills and sweats, loss of appetite and weight, and recurrent fever are classic malaria symptoms, which was ruled out by a blood smear to identify parasites. The next significant threat to rule out was Tuberculosis, a highly communicable disease which South Africa has one of the highest rates of it in the world. The blood-stained sputum was evaluated with an acid-fast stain, which can be used to identify organisms in the genus Mycobacterium, which are indicated by bright red bacilli. The Lowenstein-Jensen Medium is used for the cultivation of Mycobacterium tuberculosis and provided the confirmation that the agent that the student contracted
Upon receiving the unknown Microorganism (M.O.) #16, I prepared a slide by cleaning and drying it. Then, using a bottle of water I placed sterile drop of water on the slide and used an inoculating loop, flame sterilized, I took a small sample of the unknown growth in my agar slant and smeared it onto the slide in a dime sized circle and then heat fixed it for ten minutes. After ten minutes had passed, I collected the ingredients needed to perform a gram stain. I got the primary stain, crystal violet, and flooded my smear for sixty seconds, and then rinsed the color off with water until the water ran clear. I then flooded the smear with the mordant, grams iodine, and let that sit on the slide for sixty seconds as well. I then rinsed the grams iodine off with water and applied alcohol to the smear to decolorize the cells; however I made sure not to over decolorize and only put enough drops on the smear till the purple ran clear. I then rinsed the slide with water and flooded the smear with safranin the counter stain and let it sit for sixty seconds and then rinsed the color off with water. I blo...
One bacterium was gram negative. It underwent four different tests. These tests were the EMB test (Eosin Mehylene Blue), the Sulfur Indole Motility (SIM) test, the Urease test, and the Simmon’s Citrate Utilization test. The EMB test checks for a bacteria’s ability to ferment lactose. This test is accomplished by placing the bacteria on Eosin Methylene Blue agar. The agar is selective for gram negative bacteria and those bacteria that can ferment lactose will have colored growth, usually a metallic green sheen.
They can be found anywhere and identifying them becomes crucial to understanding their characteristics and their effects on other living things, especially humans. Biochemical testing helps us identify the microorganism present with great accuracy. The tests used in this experiment are rudimentary but are fundamental starting points for tests used in medical labs and helps students attain a better understanding of how tests are conducted in a real lab setting. The first step in this process is to use gram-staining technique to narrow down the unknown bacteria into one of the two big domains; gram-negative and gram-positive. Once the gram type is identified, biochemical tests are conducted to narrow down the specific bacterial species.
completed, the tubes are stored at 4°C until analysis of the tubes. To alylize the PCR results with
The first step to the unknown is selecting an actual organism. The best way to select a culture is based on a high-quality distribution. Equally important, shaking up the broth tube facilitates in the distribution. Upon selection, a gram check for purity is performed. Step by step instructions for this procedure can be found in Benson’s, Microbiological Applications p. 99. Furthermore, an aseptic technique must be performed for this test and the entire tests following the unknown. The purpose of this test is to differentiate between gram positive and gram-negative bacteria. The key indicator of gram-positive bacteria is a purple stain and a pink stain for gram-negative bacteria. A slide is viewed with a microscope under oil immersion. Equally
To perform this test we first did a Gram stain on our organism to determine if it was gram-positive or gram-negative. After this we performed a mixed Gram stain by incorporating our organism with a known bacteria that stained opposite of unknown. We were given the size of the known bacteria and performed a comparative analysis under the microscope to determine the size of our unknown. In my case the control was a gram-negative bacteria Escherichia coli.
A low-grade fever, weight loss, lethargy, night sweats, respiratory congestion, cough, and hemoptysis, are symptoms indicative of Tuberculosis. A positive skin test, abnormal chest x-ray and a positive sputum culture are indicators of Tuberculosis. Tuberculosis is transmitted by inhalation of respiratory droplets containing bacteria. This excerpt depicts tuberculosis and its history and prevalence.
Mycobacterium tuberculosis (M. tuberculosis) is the bacterium that causes the disease tuberculosis (TB). A distinctive characteristic of the genus Mycobacteria is the presence of a thick lipid-rich cell wall and resistance to the decolourization step of the gram stain (being acid-fast). The acid-fast characteristic of the M. tuberculosis is the result of a waxy, lipid-rich cell wall. The cell envelope of the tubercle bacilli contains a layer beyond the peptidoglycan which is exceptionally rich in lipids, glycolipids and polysaccharides. The bacterium is gram positive bacillus which is an obligate aerobe, is non-motile, a non-endospore forming and is non-capsulated. The microscopic appearance of M. tuberculosis is seen as straight, slightly curved rods approximately 3 x 0.3µm in size. In liquid culture media, the bacteria usually grow as twisted rope-like pellets known as ‘serpentine cords’. M. tuberculosis is capable of growing on a wide range of enriched culture media such as Lowenstein-Jensen medium or Middlebrook medium. The optimum growth temperature of the pathogenic organsim is 35-37°C and unlike most other mycobacteria, it cannot grow at a temperature of 25°C or 41°C. M. tuberculosis is an airborne pathogen that is transmitted from person to person, usually infecting the respiratory tract through inhalation (Greenwood, et al., 2012).
"Tuberculosis." Tests and diagnosis. Mayo Foundation for Medical Education and Research, n.d. Web. 13 May 2014. .
Tuberculosis or known as TB remains a leading cause of morbidity and mortality in the world, especially in developing countries. A combination of factors including high costs, limited resources and the poor performance of various diagnostic tests make the diagnosis of TB difficult in developing countries. According to Centers for Disease Control and Prevention (2014), one third of the world’s population is infected with tuberculosis. In 2012, nearly nine million people around the world become sick with tuberculosis disease, and there were around one point three million TB related deaths worldwide.
...f infections acquired during the hospital. Many of these studies have indicated that these infection control interventions will decrease the number of sick or dying patients related to hospital acquired infections and lower the medical cost by decreasing the stay of each patient in the hospital.
Tuberculosis is transmitted by inhalation of aerosols containing the tubercle bacilli. The required inoculum size for infection is usually high, but easily occurs with exposure to a patient who is currently infected. The products of dried aerosols, droplet nuclei, are particularly infectious because they remain in the air for an extended time, and upon inhalation easily move to the alveoli. The severe damage related to infection is caused by the reaction of the host. The tuberculosis infection has two phases, primary and secondary.
The infection control plays an important role for the prevention from bacteria and other microorganism that may affect the condition of the patient.
Tuberculosis is transmitted from person to person through airborne droplets, when a person that is infected with TB coughs, sneezes, talks, and/or sings letting tiny droplet to be released into the air(Bare, Smeltzer, Hinkle, and Cheever, 2008). TB cannot be spread through touching inanimate objects, food, or drinks (Bare et al. 2008). The person must be in the same area an affected individual is in and inspirate the droplets to be affected. Once the bacillus is inspired into the lungs, the bacilli start to multiply causing lung inflammation also known as nonspecific pneumontis (Huether et al. 2008). To cause an immune response the bacilli will travel through lymphatic system and become lodged in the lymph nodes (Huether et al. 2008). Lung inflammation causes the activation of the alveolar macrophages and neutrophils (Huether et al. 2008). Granulomas, new tissue masses of live and dead bacilli, are surrounded by macrophages, which form a protective wall. They then transform into a fibrous tissue mass, the central portion is called a ghon tubercle (Bare et al. 2008). The bacterial then necrotic, forming a cheesy mass, this mass may become calcified and form a collagenous scar (Bare et al. 2008). At this point, the bacteria becomes dormant and there is no further progression of the active disease. The disease can become active again by re-infection or activation of the dormant bacteria (Bare et al. 2008).
Microscopy will be performed on the patient to establish the type of malaria parasite and the number of these parasites in his/her blood sample. The blood sample can be extracted through a finger stab and then made into thick and thin films, and examined severally using a 100x oil immersion objective after staining them with Romanovsky stain (Warrell, Cox, & Firth, 2005, p. 734). By observation, the species of plasmodium can be seen and the number of them established