HPLC (High-performance liquid chromatography)
HPLC is a powerful chromatography technique able to separate similar substances from a mixture in a short period of time. The method require a mobile phase (liquid) and a stationary phase (liquid/solid). The stationary is phase usualy indicated by the column used, while the eluent is the mobile phase. Both phases are selected in order to best suit the sample and the purpose of the separation. The resolution and the order of the elution depends on the stationary and mobile phase selected. Substances that have a higher affinity for the mobile phase will emerge first, while others, with an affinity for the stationary phase will remain in the column longer (Meyer, 2010).
In order to force the mobile phase into the column filled with very small small particles, a high constant preassure is necessary to be applied. The basic principle is that under the same conditions, the time between the injection of the component and its elution remains constant. The output is a chart presenting the time-depending changes in the signal intensities as a consequence of substance separation. The technique can be used in qualitative and quantitative approaches, as the height and the area of each peak is proportional with the concentration of the corresponding substance (Meyer, 2010).
Mycolic acids can be recognized based on their chain length (C70 - C90), the presence of double bonds, their long side chain, their additional oxygen or methyl functions. The three main classes of mycolates from mycobacteria can be separated using „normal phase” HPLC, but characteristic peaks for MTBC can not be identified. However, „reserse phase” HPLC (rpHPLC), can separate mycolic acids according to their chain length and t...
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Paabo’s team discovered an mtDNA sequence from a finger bone they found from around 40,000 years ago, as carbon dating is one of the most commonly used methods of determining a fossil’s age. (Hammer, 70). Also, Neanderthal mtDNA is differs severely from modern human mtDNA. For example, Microcephalin is a gene for brain size during the development of the organism.
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The objective of this experiment was to perform extraction. This is a separation and purification technique, based on different solubility of compounds in immiscible solvent mixtures. Extraction is conducted by shaking the solution with the solvent, until two layers are formed. One layer can then be separated from the other. If the separation does not happen in one try, multiple attempts may be needed.
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An estimated one third of the world 's population is infected with Mycobacterium tuberculosis. In 2012 there were 9,975 cases of TB reported and of those cases 28% where Hispanic or Latino. This respiratory disease is the most common in the lungs (World Health Organization, 2014). The brain which causes tuberculosis meningitis, genitourinary TB, gastrointestinal TB, tuberculosis lymphadenitis, cutaneous TB, uterus ovarian TB and Osteo- articular skeletal bone and joints are also parts of the body that are affected (Article base, 2008). Symptoms of TB are chills, fever, night sweats, hemoptysis, cough lasting more than 3 weeks, chest pains, and weight loss (Tuberculosis, 2014). Transmission of TB is through a sneeze, a cough, speaking, or singing in which the person has the
DNA Timeline: DNA Science from Mendel to Today. (2014). Retrieved May 29, 2014, from http://www.dnai.org/timeline/
contains mitochondrial DNA (mtDNA), completely intact. Mitochondrial DNA is tougher than the DNA found in cell nuclei; it is also found in the cytoplasm of a fertilized egg and is passed only through maternal lineage. This makes it much easier for the team to study and makes testing more accurate. Paabo’s team, from Leipzig, Germany, used a method of amino acid content as a way of measuring extractible DNA from the bones. The amino acid method was a means for testing the DNA content in the fossils.... ...
Tuberculosis (TB) is an infection that can attack any part of the body, but it is normally found in the lungs (Huether, McCance, Brashers and Rote, 2008,). TB is an infection caused by a acid-fast bacillus also know as Mycobacterium tuberculosis (Huether et al. 2008) It is one of the leading causes of death in Asia, China, Indian, Indonesia and Pakistan (Huether et al. 2008). These countries show that in most cases the incidence rate is highest in young adults, and are usually the result from re-infection in recent infections. The spread of TB is attributed to the emigration of infected people from high-prevalent countries, substance abuse, poverty, transmission in crowd places, and the lack of proper medical care for the infected individuals (Huether et al. 2008).
Myobaterium tuberculosis is a nonmoving, slow-growing, acid-fast rod transmitted via aerosolization (airborne route). People who are most often infected are those having repeated close contact with an infectious person who has not yet been diagnosed with TB (Ignatavicius and Workman, 2006). Therefore, when a person with active TB coughs, sneeze, laughs, sings, or whistles, droplet become air borne and may be inhaled by others. Far more people are infected with the bacillus than actually develop active TB. The bacillus multiplies freely when it reaches a susceptible site (bronchi or alveoli). The majority of the bacilli are trapped in the upper parts of the airways where the mucus-secreting goblet cells exist. An exudative response occurs, causing a nonspecific pneumonitis (Ignatavicius and Workman, 2006). With the development of acquired immunity, further growth of bacilli is controlled in most initial lesions. Bacilli can also spread by erosion of the caseating lesions into the lung airways -and the host becomes infectious to others. Cell-mediated immunity develops 2 to 10 weeks after infection and is manifested by a positive reaction to a tuberculin test. Skin testing for tuberculosis is useful test to detect. According to Universi...
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.
Since antibiotics, such as penicillin, became widely available in the 1940s, they have been called miracle drugs. They have been able to eliminate bacteria without significantly harming the other cells of the host. Now with each passing year, bacteria that are immune to antibiotics have become more and more common. This turn of events presents us with an alarming problem. Strains of bacteria that are resistant to all prescribed antibiotics are beginning to appear. As a result, diseases such as tuberculosis and penicillin-resistant gonorrhea are reemerging on a worldwide scale (1).
Therefore it is possible to introduce different strains of mycobacteria into HeLa cells and study their behavior11. Cellular uptake analysis of M. tuberculosis has also been studied by using HeLa cells. These cells were used to identify a product of M. tuberculosis which stimulates a functional reaction in non-phagocytic mammalian cells12. The virus leads to a cytoskeletal rearrangement in HeLa cells due to recombinant mce1 protein product12. Therefore, usage of HeLa cells permits for the identification of M. tuberculosis product which triggers changes in the target cell.
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 scientific and medical progress of DNA as been emense, from involving the identification of our genes that trigger major diseases or the creation and manufacture of drugs to treat these diseases. DNA has many significant uses to society, health and culture of today. One important area of DNA research is that used for genetic and medical research. Our abi...