Transforming growth factor-beta and ROCK inhibitor in immunostaining Lab Report

Transforming growth factor-beta and ROCK inhibitor in immunostaining and microscopic analysis of adherent cells - Lab Report Example This report examined the transforming growth factor-beta and ROCK inhibitor in immunostaining and microscopic analysis of adherent cells. For a high gene dosage to be achieved, the heterologous cDNAs are normally cloned into replicate plasmids in a fashion that is relaxed and are normally existence at 15-60 copies per cell (Baneyx, 2009). Whenever the additional co-overexpression gene product is needed, ColE1 derivatives are normally put together with plasmids that are compatible and a p15A replication that is maintained at approximately 10 to 12 copies per cell. Under conditions of the laboratory, the multicopy plasmids will be distributed randomly during the division of the cell, and whenever selective pressure are lost at a frequency that is low. This may be due to multimerization (Baneyx, 2009). Whenever there is a high number of copy plasmids, the loss in plasmid can increase tremendously especially when the plasmid bone genes are toxic towards the host or significantly reduce t he rate of growth whenever cells are cultivated at densities that are high or in processes that are continuous. These problems can be addressed by using the encoded plasmid antibiotic markers resistance and the supplement growth medium supplemented to do away with the free cells of the plasmid. One key limitation of this approach involves the loss of selective pressure due to the degradation of antibiotics, leakages, or inactivation of the periplasmic detoxifying enzymes into the medium growth and the product contamination (Baneyx, 2009). This drawback could be unacceptable from a regulatory or medical point of view. In this respect, many alternative methods have been established to make sure that the cells that are free from plasmid will not overtake the culture. This means that cloning vectors will be engineered to carry repressors or genes, which leads to cell death whenever there is a loss of plasmid (Cregg, 2000). Even though, this method is proved to be vital, it could place r estrictions on the medium growth composition whenever there exist any complication and may introduce a burden metabolism on the cell through requiring transcriptions and translation of additional genes of encoded plasmids. For these problems to be circumnavigated, research has established a host strain having a conditionally essential gene in control of the promoter-operator region and a multicopy companion of the plasmid having the lac operator (Baneyx, 2009). Whenever the LacI receptor protein is titrated by encoded plasmid lac operators, it leads to the gene chromosomal expression and plasmid growth that is selective. It may also bear cells in the medium that is supplemented by the antibiotics. Another different solution to the plasmid instability problem could be a direct insertion of the genes that are heterologous within the E coli chromosomes. Even though, there exist a single vehicle delivery like the bacteriophage in this purpose there has been extremely little emphasis pla ced on the perceived notion that the dosage of the gene will always be low. In order to gain more insight on the characteristics of the E coli, this experiment was set to investigate the recombinant protein expression. Methodology. Material. The materials used for this experiment include: EcoRi/HindIII cleaned and cut pUC19 vector (V), EcoRi/HindIII cle

Sandwich report Lab Example | Topics and Well Written Essays - 1500 words

Sandwich - Lab Report Example Among the foods that have been prepared to become ready to eat include meats, sushi, cheese, cereals, salads and other produce, dry goods including candies and biscuits, and meals that are ready to eat. On the other hand, salads and sandwiches are common ready to eat food that, due to their capacity for contamination, have been associated with strict guidelines for their preparation. Those guidelines conform to regulations that have been put in place in places like New York, and cover such things as changing/replacing gloves, prohibitions against the use of bare hands during the preparation process, and the kinds of food that are considered for inclusion in government codes of sanitation relating to the preparation of such ready to eat fare. It is worth noting that government codes have prescriptions for the degree to which food are to be heated in order to be considered safe for consumption. Since ready to eat food is generally not heated to meet those minimum temperature of reheati ng standards, they are subject to more rigorous regulations in terms of handling to prevent ready to eat food being contaminated with pathogens that can cause illness on wide scale. Food handling in preparation and in transport are by far the biggest sources of contamination when it comes to ready to eat food (Colorado Farm to Market, 2013; NY State Department of Health, 2005; Schaub, 2010; UK Government, 2008). Enterobacteriaceae are a group of pathogens that are used as indicators for when food has not been cooked adequately, or else when food has been subject to contamination after the food had been processed. E.coli, on the other hand, is a pathogen that when present indicates poor hygiene, lack of sanitation, and heat that has not been adequate to kill off the bacteria during the processing of food. Other pathogens include coagulase-positive staphylococci, c. perfingens, b. cereus, v. parahaemolyticus, campylobacter spp, salmonella spp, and L. monocytogenes (NSW Food Authority, 2009; ACT Health, 2002). These same pathogens seem to cross geographic boundaries, and share in common many of the pathogens that are found in ready to eat fare in other nations, such as Hong Kong, where ready to eat food is screened for a similar set of pathogens, including b. cereus, c. perfingens, campylobacter spp, e. coli, v. cholera, salmonella, and L. monocytogenes (Centre for Food Safety, 2007). The Canadian authorities include shigella, v. cholerae, y. enterocolitica, c. parvum, giardia lamblia, hepatitis, and scombroid poisoning to the list of pathogens above, with the most common symptoms and effects of contamination and infection in people being vomiting, nausea, diarrhea, wound infection, and gas gangrene (Manitoba Agriculture, Food and Rural Initiatives, n.d.). In the US, meanwhile, there is an intense focus on salmonella, e coli and listeria monocytogenes as the pathogens that most commonly infect ready to eat food, including produce. The lines of defense arrayed aga inst such pathogens in food include thermally killing the pathogens, making use of the so-called bacteriophage treatment, and the use of so-called antimicrobial GRAS agents (Food Safety Research Information Office, 2010). It is worth noting that in some of the bacteriological guidelines that were considered for this paper, emphasis is given on rating the quality of the food as