Causes Of Biofilm Formation

Enterobacter cloacae is a common Gram-negative bacterium. It belongs to the family Enterobacteriaceae. Enterobacter cloacae is an opportunistic bacteria and has emerged as a nosocomial pathogen within the last decade.1 E. cloacae is more prominant within intensive care units, especially those patients who are on mechanical ventilation.1 Antibiotic-resistance is one of the well-known features of this microorganism.1 A trail was conducted to determine how exactly Enterobacter cloacae works in regards to its pathogenicity, but unfortunately only a few mechanisms are understood. The few processes that are known include its ability to produce biofilms as well as secrete numerous cytotoxins.1

Biofilms play a crucial role in the persistence of lung infections in CF patients due to the protective extracellular matrix that is formed by the bacterial community (5). This barrier limits the penetration of antibiotics and results in varying nutrient gradients, allowing for a diverse range of bacteria (5). Bacteria inside this biofilm are able to sense the presence of other cells, and alter their properties accordingly to suit the environment. This is particularly interesting as the bacterial communities within a biofilm may compete with each other for dominance in the biofilm (6). Therefore, bacterial competition may impact the treatment and actions needed to treat biofilms in the lungs of CF patients

The bacterium is capable of producing biofilms that allow microorganisms to stick to solid surfaces forming an attachment, which is enclosed by a slime layer ("Staphylococcus epidermis"). Biofilms protect pathogens from being destroyed by disinfectants inside human bodies ("Staphylococcus epidermis"). In other words, biofilms aid pathogens in causing diseases by releasing microbial products ("Staphylococcus

When determining which bacteria I wanted to use for this experiment I had to decide on E.coli bacteria which is gram negative and staphylococcus a gram positive bacterium. These were chosen because they are safe enough to grow in a college laboratory and were supplied by the technician. Gram negative bacteria has an outer membrane making it more resistant to antiseptics and antibiotics, it also makes it more fatal to the human host it is inhabiting. Whereas gram

Aseptic Technique and Culturing Microbes(1) experiment was followed as stated in the lab manual from Clinical Microbiology Class C-453. Aseptic technique was initiated at the beginning of each experiment. Starting by cleansing the work surface with disinfected wipes to prevent cross contamination each time. Utilizing the gloves and personal protective equipment assisted in maintaining a pure culture during the series of experiments. The first step, was to grow the yeast and bacteria cultures. The materials used for the Aseptic Technique Experiment(1) were: test tube rack, 5 mL nutrient broth tubes, pipettes, a lit tea light, Fleischmen’s rapid yeast pack, E. Coli tablet and the S. epidermidis tablet. Started by activating the yeast, by placing the content of Fleischmen’s yeast bag in a disposable cup. Then added approximately 60 mL of warm tap water into the disposable cup. To assist in mixing the two items, I carefully swirled the cup. Once the mixture was combined, it then was left alone for around 10 minutes or until it was frothy. Each nutrient broth tube was labeled with the correct name of the microorganism that was cultured in that tube and dated. The S. epidermidis was selected first, to be cultured. Taking one of the 5mL nutrient broth tube in one hand, the pipette in other hand. The cap was removed with the same hand that had the pipette. Utilizing a lit tea light, like a bunsen burner, I flamed the mouth of the nutrient

The formation of biofilms is not random but can be predicted by the process above. The biofilms become attached to surfaces because of gravity, or bacteria that have a negative charge. The bacteria senses and goes to the highest concentration of nutrients.

Often scientists work with bacteria that do not come in a labeled test tube— for example, bacterial samples taken from infected human tissue or from the soil—and the scientist must then identify the unknown microorganism in order to understand what behavior to expect from the organism, for example, a certain type of infection or antibiotic resistance. However, because of the relatively few forms of bacteria compared to animals and because of the lack of bacterial fossil records due to their asexually reproductive nature, the taxonomy used to classify animals cannot be applied to bacteria (Brown 275). In order to classify unknown bacteria, a variety of physiological and metabolic tests are available to narrow a sample down from the fathomless number of possibilities into a more manageable range. Once these tests have been performed, the researcher can consult Bergey’s Manual of Determinative Bacteriology, a systematically arranged and continually updated collection of all known bacteria based on their structure, metabolism, and other attributes.

In the EMB agar test, two distinct colonies due to their different in color were observed. For the one with black colonies, it was determined to be lactose fermenters, because only acid production from lactose fermentation would result in this color. As for the other colonies, they appeared to be either colorless or pinkish, this indicates that they are either sucrose fermenter or non-coliform Gram-negative strains because of their inability to ferment lactose.

Bacterial biofilms are a major barrier in terms of wound healing. During cell to cell

1. Topic: title of topic clearly stated area / branch of Biology clearly stated Title of topic: Dust mite Allergy (Immune System) Area of Biology topic is from: Human Body - Immunology 2. Brief Introduction: (max 200 words) (2m) history or background of topic with mention of dates / context Background Allergies are increasing and there is no cure for them, affecting as many as 30 percent of adults and 40 percent of children. Allergies are the result of the immune system’s response to a substance. The immune system is made up of a complex and vital network of cells and organs that protect the body from infections.

Bacterial urinary tract infections represent the most common type of nosocomial infections. Often, the ability of bacteria to both establish and maintain these infections are directly related to biofilm formation on indwelling devices or within the urinary tract itself (30). Enterococci (especially E. faecalis) are one of the main causative agents of urinary tract infection and Catheter-associated urinary tract infections (CAUTIs) besides gram-negative pathogens (31, 32). In these infections Biofilm provides a favorable milieu for microbial survival within the host as the organisms are shielded from the host immune response, as well as antibiotics and antimicrobial agents (33, 34). Several studies conducted to introduce main virulence genes of enterococci that are associated with biofilm formation in these bacteria (11, 13,-17), but virulence mechanism and related genes for biofilm formation are not well understood (35). In this study we investigated biofilm formation of clinical enterococci isolates isolated from Urinary tract infections. These strains were characterized for presence of adhesions and secretory virulence factors. Isolates had diverse presence of virulence from lack to highest amount of virulence genes. Several previous studies investigated relation of virulence genes and biofilm formation, especially presence of esp and gel. Enterococci esp has been implicated as a contributing factor in colonization and persistence of infection within the urinary tract

Broth cultures of E.coli, Micrococcus luteus and Vibrio natriegens were streaked onto the respective sections. The plate was then incubated at 37oC for 48 hours. The process was then repeated on nutrient agar plates with 5, 6.5 and 10% salt.

Allergen immunotherapy can be described as a therapeutic technique used to treat symptoms of allergies and reduces the underlying immunological hypersensitivity (1). In this method the patients are provided gradually increasing levels of the sensitized allergen, the dose of which is properly administrated. Consequently the immunological response towards this allergen decreases. The issue with the normal treatment against allergies including the anti allergy drugs and an immunomodulatory agent such as anti-IgE is that they only temporarily decrease the symptoms of the allergies, however if the drug intake is discontinued, these symptoms are evident again (1). Contrary to the normal anti-allergy treatments, it is suggested that immunotherapy may be effective in long time remission (2, 3), reduction in the probability of developing new sensitizations and prevention of rhinitis conversion to asthma (4, 5). Hence suggesting that immunotherapy is a more effective way to treat allergies and their associated response in comparison to the traditional anti-allergic treatments. The two methods through which the allergen

An ideal restorative material should have a property of adhesion to tooth structure and an ability to withstand the occlusal forces. However, some therapeutic and caries preventing efficacy might be desirable. Glass ionomer cement has been shown to produce some degree of antibacterial effect due to release of fluoride [3]. Several studies have been done to increase the antimicrobial effect of GIC without compromising the physical properties of the restoration. Takahashi Y [4] in 2006 and Tuzuner T [1] in 2011 advocated that the incorporation of chlorhexidine into GICs has resulted in an excellent antibacterial effect in vitro. Frencken JE [5,6] observed that microorganisms counts in both affected and infected dentine were significantly

According to the National Institute of Health (NIH), the decreasing occurrence of infections in Western nations and more recently in developing nations is at the heart of the decreasing incidence of both autoimmune and allergic diseases. The hygiene hypothesis is at both based upon epidemiological data, particularly migration studies. Display that test subjects migrating from a low-incidence for autoimmune and allergic disease to a high-incidence nation acquire the immune disorders with a high incidence.