Questions on Microbiology - Essay Example

? Revision Questions- Microbiology How are antibiotics developed for use in clinical practice? To what extent have these achieved the “ideal” antibiotic? Antibiotic development entails an involving task that requires adequate resources and support from concerned parties (Tenover, 2006). The resources encompass time and other physical requirements, which will enhance the effectiveness and precision required all through the process. Development of antibiotics especially for clinical purposes normally differ radically according to the final end use, though, in some incidents experts may generalize them (Tenover, 2006, S9). This is according to fine details and addictives, which ought to bear for effective facilitation of the intended role. Primarily, conventional method presently is fermentation process, besides numerous ways, which are almost similar but due to patent law, experts have withheld them. Fermentation entails separating required microorganism, enhancing culture growth besides refining and finally isolating the resultant antibiotic (Tenover, 2006). The process ought to be in a sterile environment, since the external microbes usually tend to interfere with the fermentation procedure. Prior the fermentation, the required antibiotic ought to be isolated and kits population augmented by numerous times. This is via taking already existing culture from the cold-stored organisms where growing the initial entails the transfer of organism to an agar-containing plate. Then, preparation of the organisms’ food via putting the initial culture in a flask coupled with other necessary nutrients and food meant for growth while shaking. This makes a suspension prior transferring to the seed tanks for growth. Seed tanks mainly their structure material entail steel or any other material that will not corrode easily that contain all the necessary conditions and material, which a certain organism might require like warm water, carbohydrates (lactose, glucose or sugars). Additionally, they do have extra vital carbon sources, for illustration, acetic acid, alcohols, -HCO3, N2 and NH4 salts (Tenover, 2006, S4). The steel vessels normally comprises of stirrers that normally keep the medium in motion for 24-28 hours. Afterwards the contents goes to the primary fermentation process, which encompasses of almost similar improvised tanks and filled with the former contents prior inception of conducive surroundings for growth. Mainly, the temperature ranges amid 23-27.2 ° C with continued agitation coupled with injection of sterilized air. Here residence time ranges amid 4-5 days prior undertaking isolation or purification before refining and controlling its quality, which depends on the antibiotic type (Tenover, 2006, S8). The process’ applicability is effective, though, depending on the antibiotic may have some minor variations that would entail modifications. They aim to enable certain yields are obtainable and with the desired quality. This is especially via the final steps, which mostly varies with the antibiotic type, hence ensuring each good quality and yield is viable (Tenover, 2006, S5). Fermentation process is reliable owing to its nature of action, which entails boosting or enhancing through providing necessary requirements for its inception. Discuss the mechanisms of antibacterial action giving details of the targets and action of at least 2 antibacterial agents Primarily, antibacterial modes usually differ with agent and encompass four modes. 1. Inhibiting cell wall They comprise penicillin, Cephalosporins, Carbapenems, and Monobactams where they normally destroy the wall of their target (Tenover, 2006). Consequently, ensuring that they do not allow any external barriers, which enemies to the body might create as a way of protecting themselves against various attacks. Conversely, antibiotics assuming this mechanism normally destroy their cell walls, thus terminating their survival and rendering them exposed to the drug. Alternatively, it is the mode of interfering with the enzymes responsible for the formation of peptidoglycan layer meant for protection by the bacteria. 2. Protein synthesis disruption/inhibition This is almost similar to mechanism mentioned above, which deals with inhibition of cell wall synthesis, but via binding. This normally intercepts the key steps required in the making of cell wall, which encompass interfering with D-alanine residues liable for a stable and strong structure. Some of these agents comprise mupirocin and aminoglycosides (Tenover, 2006). 3. Nucleic Acid synthesis obstruction It entails interference of making of DNA via application of its double toxic DNA strand, which halts the necessary replication, for illustration, fluoroquinolones. 4. Metabolic path way interference Sulfonamides normally interfere with the necessary DNA process via shunning the occurrence of ample folic acid making. 5. Destroying of a Bacteria’s membrane Compared to the aforementioned modes, this method seems unique in its action, hence rare in application. Its action entails making the bacteria’s membrane permeable, which causes the leakage of its necessary contents and rendering it inactive and yielding utter destruction. Primarily, polymyxins normally work in this mode, which yields to the complete elimination of the bacteria and making its existence in the region almost intolerable. Discuss the major reasons why antibiotic resistance occurs in bacterial pathogens in a hospital environment. What steps can be taken to resolve the problem? Bacteria due to prolonged exposure to similar environment and agents applied in counteracting their effects normally become resistant. This is via developing various mechanisms, which will cancel the agents’ destructive effects and result or secrete their own enzymes (Tenover, 2006). These will neutralize or act as retaliation to the already staged elimination strategy against them. Mainly, the organism attains genes retaliating enzymes like Beta-lactamases that acts on the agent prior it starts it action. This renders the process of disinfecting to be in vain regardless of the amount that personnel may intent to apply (Tenover, 2006). Secondly, the organism may extrude the antibiotic agent from its membrane prior making any attempt of reaching the target where it will start its intense impact. The possible actions of their remedy entails termination of the applying the already ineffective drug and commence for a meticulous research which will ascertain the correct and effective method that would be adequate. Compare and contrast the pathogenesis of two named bacterial diseases. Cellulitis Lyme Disease Bacteria streptococcus or staphylococcus Borrelia burgdorferi Transmittance Insect bite or via an open wound Bites by infected ticks (from mice/deer) Symptoms Swelling, redness, warm skin, tenderness and pain. Bull's-Eye shaped rash on the affected part. Cellulitis is a skin malady, primarily caused by staphylococcus, which finds its way into the body via an open would or an insect bite. Discuss mechanisms of action of any named bacterial toxin. Borrelia burgdorferi toxins (Lyme Disease) Fatty cells especially those of nervous systems normally attracts the toxins where due to the severity nature they do disrupt the necessary working of the selected sites in the brain. Hence, yielding to mental malfunction because of altered structure and chemical cells. This affects the major neurotransmitters necessary in the normal mental functions. Discuss the sensitivity and specificity of diagnostic tests for micro-organisms and, using particular examples, show how they may be compromised. Bacterium susceptibility normally indicates effectiveness of a drug (Tenover, 2006, S3). Mainly, this entails small wafers containing the antibiotics introduced to the growing bacteria. The ease with which the information of inhibition ring forms around the wafers will be an indication of the sensitivity, thus poor growth. This method may fail to yield to the intended results due to impurities that may react with the wafers, hence showing giving poor results. Discuss the phenomenon of Quorum sensing as it relates to the expression of virulence. It is a communication mode mainly evident among the simple lives like bacteria, which entails the individual cells secreting certain fluids and normally detects their general population. Utilizing simple words and according the nonprofessional’s version, it may imply how bacteria and similar life forms normally communicate. Bacteria normally apply this method to gather adequate information from its inhabitance, which will enable it adopt sound tactics that will aid in their survival. For illustration, suppose the environment might have other microorganisms, the former will adopt sound survival tactics that will aid in shunning obnoxious secretions from the neighboring identities. Discuss the development of antibiotics in a historic context. Man’s advancement in knowledge regarding how to tackle diverse maladies that normally challenge his survival has managed to discover helpful resolutions. Initially, the applied resolutions entailed herbal forms, but these some were antibiotics, though, they could not be able to expound and draw strong conclusions. Clear antibiotics’ history started with the WW11, where wounded soldiers and other personnel immensely applied the knowhow in shunning similar related infections prior their victims reached to designated health centers. Since then to date, antibiotics and their maladies’ ever changing bacterial infections has really revolutionized medicine (Tenover, 2006). This emanates from the struggle and efforts meant to counteract the effects of bacterial resistances that normally alter with prolonged use of a similar medicine. Hence, the bacteria either secreting selected toxins that will render the medicine ineffective or developing cocoons having high resistance. Late 1800s This marked the commencement of antibiotics study, which entailed linking causation of numerous maladies to microbes. Hence, prompting researchers to embark on intensive search of medicine that would terminate those microbes. 1871 Joseph Lister tried to unveil the theory behind the phenomenon regarding contaminated urine as a hindrance to bacteria growth. 1890s Rudolf Emmerich and Oscar Low emerged as the first scientists to synthesize antibiotic, though, it did not work as necessitated. 1928 Alexander Fleming made a remarkable breakthrough that encompassed unveiling an antibiotic meant to treat wounds. His study culminated to the famed penicillin by studying petri dishes’ content after returning from holiday. 1935 Gerhard Domagk developed sulfa drug. 1942 Howard Florey erected penicillin plant that augmented its yields for commercial purposes. 1943 Selman Waksman originated with Streptomycin meant to treat TB, but its effects proved extremely adverse. 1955 Lloyd Conover originated with the most advocated Tetracycline in America; an antibiotic. 1957 Nystatin underwent patent after famed to tackle fugal infections, which had proved a bother especially via disfiguring and disabling the patients. 1981 The patented amoxicillin by SmithKline Beecham proved significant breakthrough, which prompted its intensive application especially in 1998. What is an ideal antibiotic? Discuss the extent to which this has been achieved in practice. It is an antibiotic possessing bactericidal coverage from the time of inception until one reaches the hospital and necessary remedy actions taken. This is via ensuring the agent has high penetrative power through the skin, which will prevent any infections that might develop prior treatment. Primarily, this is by making storage, administering and availability is simple for the users especially those in the battlefields. Besides, it should also be cost effective. Discuss the major modes of action of antimicrobial drugs. 1. Hindering cell wall synthesis Primarily, these attack the external wall; hindering the microbes from having any chances of survival of affecting the host. 2. Hindering of protein synthesis This action is entails barrier creation where the ribosomes do not have adequate time meant for their synthesis especially the microbes’ cells. 3. Destruction of plasma membrane It encompasses the exposing of the microbe’s internal contents via destroying the membrane, thus offering no survival chances. 4. Disrupting the Nucleic Acid making, this enhances the development of the microbes and their survival. This denies microbes the conditions meant for enhancing their survival. Discuss the mechanisms of antimicrobial resistance in bacteria. Resistance normally emanates from antibiotics devising new and excellent adaptive mechanisms that will cancel effects of drugs. This may be via secreting enzymes that normally with time render the antibiotics ineffective. The enzymes become severe with more interaction with the injected antibiotics where at advanced stages they have utterly overpowered them. Table 1: Case Studies' Cases summarized in a Table Patient Hepatitis Type Diagnosis Treatment 1 B Blood tests on the patient Vaccine and in the incidents when it is severe, involving diarrhea; injection of electrolytes is the remedy. 2 A, B or C Blood Screen Depending on the type 3 B Blood tests on the patient Vaccine and in the incidents when it is severe, involving diarrhea; injection of electrolytes is the remedy. 4 C Screen tests Usually clears by itself, but the chronic conditions ought to take medications. 5 B Blood tests on the child to ascertain any evidence. Vaccine and in the incidents when it is severe, involving diarrhea; injection of electrolytes is the remedy. 6 Acute Fulminant Vomiting, Nausea and abdominal pain Relieving the ailment’s symptoms and Adequate fluids intake References Tenover, F. C. 2006. Mechanisms of Antimicrobial Resistance in Bacteria. The American Journal of Medicine 19 (6A), S3-S10. Read More