CHAPTER –I
1.1-INTRODUCTION
1.1.1-HISTORY:
Metronidazole,a 5 nitroimidazole,was discovered in 1950ʹs.It continous to be an important and frequently used antibiotic for treatment of infections caused by anaerobic bacteria.Metronidazole was discovered because of its activity against protozoans .However,a patient being treated with Metronidazole for Trichomonas vaginalis vaginitis,a protozoan infection,was noted to have marked improvement in her gingivitis,which was caused by anaerobic bacteria.This led to investigations of Metronidazoles activity against anaerobic bacteria.
Mascaratti OA.Bacteria verses Antibacterial Agents:An Integrated Approach.Washington,DC;ASM Press;2003.
[Antibiotics Basis for Clinicians:The ABCs of Choosing the Right Antibacterial Agent By Alan.R.Hauser page 92 read on 23rd Feb,2014]
Metronidazole is a drug widely used for the treatment of infections caused by anaerobic organism either(a)protozoa such as Trichomonas vaginalis, which provokes vaginal discharges,and Entameoba Histolytica,causing ameobic dysentry or (b)bacteria,e.g in abscesses and tissue necroses caused by Bacteroids fragilis and antibiotic induced pseudomembranous colitis(Clostridium difficile).The ultimate target may be DNA in bacteria and possibly,Carbohydrate metabolism in protozoa.
Metronidazole is a small molecule that can passively diffuse into bacteria.An important component of its structure is nitro group that extends from the core five membered ring,this
In the last decade, the number of prescriptions for antibiotics has increases. Even though, antibiotics are helpful, an excess amount of antibiotics can be dangerous. Quite often antibiotics are wrongly prescribed to cure viruses when they are meant to target bacteria. Antibiotics are a type of medicine that is prone to kill microorganisms, or bacteria. By examining the PBS documentary Hunting the Nightmare Bacteria and the article “U.S. government taps GlaxoSmithKline for New Antibiotics” by Ben Hirschler as well as a few other articles can help depict the problem that is of doctors prescribing antibiotics wrongly or excessively, which can led to becoming harmful to the body.
AIM – The aim of the experiment is to determine the relative effectiveness of several anti-microbial substances on developing pathogens. (E. coli)
Effect of 5-Fluorouracil, Penicillin G and Amphotericin on the growth of Pythium and Micrococcus luteus
There are barriers to treating BV that add to the challenges providers face when treating the condition. Unfortunately, metronidazole efficacy is decreasing due to resistance.13 Certain organisms have been
The purpose of this report is to analyse the growth of the bacteria known as Citrobacter Freundii as well as distinguishing what antibiotics effect its growth. This will be done so by answering the following question after completing its associated experiments. This question includes: what antibiotics are most effective in denaturing the bacteria? It has been predicted that chloramphenicol will be the most effective due to the fact that its medical uses are treating meningitis which is an infection caused by Citrobacter freundii. After conducting the experiments it was found that the chloramphenicol antibiotic was the most effective in denaturing the bacteria, although streptomycin was also affective. However, none of the other antibiotics were able to halt the growth of the bacteria.
Yes: Discussion and summary of evidence about studies on bacterial agents, antimicrobial resistance and considerations in selection of an antibiotic regimen.
In this study, Avycaz (Ceftazidime/Avibactam) is an alternative option for treatment in complicated intraabdominal infections with metronidazole and in complicated urinary tract infections. 476 patients completed the study and received Ceftazidime-Avibactam and metronidazole. 477 patients completed the study and received meropenem. Patients with normal renal function received 2000 mg of Ceftazidime and 500mg Avibactam as a 2-hour intravenous infusion every 8 hours. This was followed by metronidazole 500 mg IV infusion every 8 hours. The meropenem group received 1000mg as a 30-minute intravenous infusion every 8 hours. Dosage adjustments were made for patients with a creatinine clearance30 to 50 ml/min. Patients requiring renal adjustments received 1000mg Ceftazidime plus 250 mg of Avibactam in a 2-hour intravenous infusion every 12 hours. Patients receiving meropenem with renal impairment received 1000mg, 30 minute infusions every 12 hours. The duration of treatment with meropenem was 8.3 days and for Ceftazidime-Avibactam plus metronidazole it was 8.0
Patients were treated with Voriconazole, an antifungal therapy, with the intial dose being 6 milligrams per kilogram every 12 hours. Blood serum levels were measured on the fiifth day of treatment and levels of the drug should range from 2 to 5 mcg/ml. Levels higher than 5mcg/ml could cause toxicity including hallucinations and other adverse effects on the central nervous system. It was recommended that most patients should start with IV voriconazole, however patients with mild disease could start with oral voriconazole at their prescribers discretion. Liposomal amphotericin B was strongly suggested to be given in addition to voriconazole to patients who presented with severe disease, didn’t improve, or experienced clinical deterioration. Duration of treatment is very much dependent on the individual and can range from three to six months depending on serverity of the infection, and any underlying immunosuppression.
Antibiotics are important for the treatment of bacterial infections, and it is therefore important to know how different antibiotic works in different contexts. Different kinds of bacteria are affected to different degrees by different antibiotics, and it may therefore be useful to know which antibiotic that attacks the bacteria. The purpose of this report is to analyze how antibiotics including Chloramphenicol and Ampicillin affect the growth rate of bacteria Escherichia coli and Bacillus subtilis. Which antibiotic is the most effective or least effective in inhibiting the growth rate of these two bacteria respectively?
Triple therapy with metronidazole and either bismuth subsalicylate or bismuth subcitrate plus either amoxicillin or tetracycline for 14 days eradicates H pylori infection in 70–95% of patients. An acid-suppressing agent given for 4–6 weeks enhances ulcer healing. Proton pump inhibitors (such as omeprazole) directly inhibit H pylori and appear to be potent urease inhibitors. Either 1 week of a proton pump inhibitor plus amoxicillin and clarithromycin or of amoxicillin plus metronidazole also is highly effective [51].
Tetracyclines and erythromycin are the most commonly used oral antimicrobials. In many cases, long-term treatment is needed to maintain remission. The long-term use of antimicrobials is not well tolerated, however, because of side-effects, including gastrointestinal intolerance,
Three drugs that are usually prescribed to treat this bacterial infection include azithromycin, doxycycline, or ofloxacin. This infection is commonly are cured by antibiotics.
(e,f, g ). Voriconazole has both oral and IV formulations while Posaconazole is available as an oral suspension, delayed-release tablets and, an IV formulation (h). Posaconazole doses is taken as oral suspension is taken 3 times daily or delayed-release tablet is taken once daily and IV infusion once daily (k). Voriconazole is taken as IV every 12 hours (k). A clinical trial had shown that posaconazole prevent the development of IFI more effectively compared to fluconazole or itraconazole as well as improve overall survival, but posaconazole was found to result in more serious side effects (i). One the other hand, there is no clinical trial conducted to know the effect of Voriconazole on AML patients (e). There is clinical trial conducted on patients who had hematopoietic cell transplantation, many of them have AML (j). The study compared between voriconazole versus fluconazole; there was less fungal infection (Aspergillus infections) in voriconazole group compared to fluconazole with no overall improvement in fungal-free survival period (j).
Trimethoprim-sulfamethoxazole (co-trimoxazole), a lipophilic antibiotic, acts against a wide array of gram-negative bacteria and is commonly used in patients with CGD.2 Due to decreased activity of the reduced NADPH oxidase, macrophages present in CGD patients are able to phagocytize (eat) catalase-positive microbes, but are unable to remove them forming granulomas. Although the Nocardia in Sam’s case was gram-positive, prophylactic use of co-trimoxazole has been proven effective in patients with x-linked and autosomal-derived CGD.4 Antifungal agents (e.g., itraconazole), coupled with steroids, are useful in the removal of fungal infections and inflammation. Additionally, routine use of antifungal agents and antibiotics help to decrease overgrowth of pathogenic agents while maintaining nonpathogenic gut
Isolates of Trichomonas vaginalis that belonged to type 1 were easier to detect with commonly empolyed diagnostic procedures (such as wet mount) and may signify symptomatic individuals with high parasite loads. On the other hand, those belonging to type 2 necessitated higher concentration of drugs to achieve lethal effect on the parasite, hence they may be linked to metronidazole resistance.