Developed and produced by http://www.MechanismsinMedicine.com Animation Description: This animation starts with the explanation of bacterial cell wall synthesis, the process targeted by ß-Lactams. Structurally, most bacteria consist of a cell membrane surrounded by a cell wall and, for some bacteria, an additional outer layer. Internal to the cell membrane is the cytoplasm which contains ribosomes, a nuclear region and in some cases granules and/or vesicles. Depending on the bacterial species, a number of different external structures may be found such as a capsule, flagella and pili. In gram negative bacteria, the gap between the cell membrane and the cell wall is known as the periplasmic space. Most gram positive bacteria do not possess a periplasmic space but have only periplasm where metabolic digestion occurs and new cell peptidoglycan is attached. Peptidoglycan, the most important component of the cell wall, is a polymer made of N-acetyl muramic acid alternating with N-acetyl glucosamine which are cross-linked by chains of four amino acids. The function of the bacterial cell wall is to maintain the characteristic shape of the organism and to prevent the bacterium from bursting when fluid flows into the organism by osmosis. Synthesis of peptidoglycan and ultimately the bacterial cell wall occurs in a number of stages. One of the first stages is the addition of 5 amino acids to N-acetyl muramic acid. Next, N-acetyl glucosamine is added to the N-acetyl muramic acid to form a precursor of peptidoglycan. This peptidoglycan precursor is then transported across the cell membrane to a cell wall acceptor in the periplasm. Once in the periplasm, the peptidoglycan precursors bind to cell wall acceptors, and undergo extensive crosslinking. Two major enzymes are involved in crosslinking: transpeptidase and D-alanyl carboxypeptidase. These enzymes are also known as penicillin binding proteins because of their ability to bind penicillins and cephalosporins. Eventually, several layers of peptidoglycan are formed all of which are crosslinked to create the cell wall. Gram positive bacteria have many more layers than gram negative bacteria and thus have a much thicker cell wall. Beta-lactam antibiotics include all penicillins and cephalosporins that contain a chemical structure called a beta-lactam ring. This structure is capable of binding to the enzymes that cross-link peptidoglycans. Beta-lactams interfere with cross-linking by binding to transpeptidase and D-alanyl carboxypeptidase enzymes, thus preventing bacterial cell wall synthesis. By inhibiting cell wall synthesis, the bacterial cell is damaged. Gram positive bacteria have a high internal osmotic pressure. Without a normal, rigid cell wall, these cells burst when subjected to the low osmotic pressure of their surrounding environment. As well, the antibiotic-penicillin binding protein complex stimulates the release of autolysins that are capable of digesting the existing cell wall. Beta-lactam antibiotics are therefore considered bactericidal agents. Bacterial resistance to beta-lactam antibiotics may be acquired by several routes. One of the most important mechanisms is through a process known as transformation. During transformation, chromosomal genes are transferred from one bacterium to another. When a bacterium containing a resistance gene dies, naked DNA is released into the surrounding environment. If a bacterium of sufficient similarity to the dead one is in the vicinity, it will be able to uptake the naked DNA containing the resistance gene. Once inside the bacterium, the resistance gene may be transferred from the naked DNA to the chromosome of the host bacteria by a process known as homologous transformation. Over time, the bacterium may acquire enough of these resistance genes to result in a remodelling of the segment of the host DNA. If this remodelled DNA segment codes for cross-linking enzymes (i.e. penicillin binding proteins), the result is the production of altered penicillin binding proteins. These altered penicillin binding proteins can still cross-link the peptidoglycan layers of the cell wall but have a reduced affinity for beta-lactam antibiotics thus rendering the bacterium resistant to the effects of penicillin and other beta-lactam agents. This transfer process has resulted in penicillin-resistant S. pneumoniae through the acquisition of genes from other naturally occurring penicillin-resistant Streptococcus species. A second important mechanism by which bacteria become resistant to beta-lactam antibiotics is by the production of enzymes capable of inactivating or modifying the drug before it has a chance to exert its effect on the bacteria. View animation to read more.
Просмотров: 708055 Mechanisms in Medicine
At GoldBio, we make sure each of our products are thoroughly tested to the highest standards. In addition to a typical certificate of analysis (COA), we also test our antibiotics through a modified version of the Kirby-Bauer method, also known as the disk diffusion method. The test compares the antibiotic's ability to prevent bacterial growth to a common set of standards created by the Clinical Laboratory Standards Institute (CLSI) in order to assure its functionality at a certain concentration. As a control, we use a strain sensitive to the antibiotic to determine its effectiveness and a resistant strain to assure it is the correct substance. Each lot is tested with this procedure. Visit the website at: http://www.goldbio.com/GoldBio-Video-Library/2/testing-antibiotic-using-disk-diffusion-assay-kirby-bauer-method **Update November 2014** Rather than going through the steps addressed in the video, this blog will just highlight important things to consider so you’re prepared to test when the time comes - https://www.goldbio.com/blog/120/old-antibiotics-wont-spoil-research-with-this-test **Update August 2017** Here is the equipment used in this video: -6 mm filter paper discs -sterile petri dishes -agar plates with no antibiotic -sensitive and resistant bacterial cultures -antibiotic to test and antibiotic for control Other items out on the bench is a Bunsen burner, lighter, tube racks, thermometer, pipette, pipette tips, antibiotics solution, forceps, ethanol, flow hood (optional) and a marker to label discs
Просмотров: 300314 Gold Biotechnology, Inc.
A lecture covering mechanisms of antibiotic resistance, principles behind susceptibility testing including understanding the MIC, interpretation of antibiotic susceptibility reports, and the factors contributing to increasing antibiotic resistance worldwide.
Просмотров: 119621 Strong Medicine
A time-lapse of the Kirby-bauer test done with E. coli and S. aureus. The Kirby-Bauer test uses Mueller-Hinton agar to test a bacterium's susceptibility to antibiotics by using discs that have antibiotics in it. Antibiotics can work in one of two ways: they either slow down growth (bacteriostatic) or kill the bacteria (Bactericidal). A lot of antibiotics target the thick peptidoglycan layer of the cell wall in gram positive organisms, which makes gram negative bacteria more resistant to these antibiotics. If the bacteria is susceptible to the antibiotic, it will create a zone of inhibition which is the area around the antibiotic disc where the bacteria did not grow. A larger zone indicates greater susceptibility. Cultures were grown at approximately 37 degrees Celsius.
Просмотров: 20787 Sci- Inspi
Просмотров: 11719 Zoe Weiss
Determination of MIC by Broth Dilution Method Demonstrated by: Dr.Mohammad Aladawi Recorded By: Ahmed Abo El-Yazid Under Supervision of: Dr.Rasha Brawa Head of Microbiology & Immunology Depratment Faculty of Pharmacy Mansoura University
Просмотров: 19834 جامعة المنصورة Mansoura University
VANCOMYCIN - Quick review Vancomycin is a bactericidal glycoprotein that binds to the d-Ala-d-Ala terminal of the nascent peptidoglycan pentapeptide side chain and inhibits transglycosylation. Vancomycin is indicated for the treatment of serious or severe infections caused by susceptible strains of methicillin-resistant (beta-lactam-resistant) staphylococci. It is indicated for penicillin-allergic patients, for patients who cannot receive or who have failed to respond to other medications, including the penicillins or cephalosporins, and for infections caused by vancomycin-susceptible organisms that are resistant to other antimicrobials. Vancomycin is indicated for initial therapy when methicillin-resistant staphylococci are suspected, but after susceptibility data are available, therapy should be adjusted accordingly. Vancomycin is effective in the treatment of staphylococcal endocarditis. Its effectiveness has been documented in other infections due to staphylococci, including septicemia, bone infections, lower respiratory tract infections, skin and skin structure infections. When staphylococcal infections are localized and purulent, antibiotics are used as adjuncts to appropriate surgical measures. Vancomycin has been reported to be effective alone or in combination with an aminoglycoside for endocarditis caused by Streptococcus viridans or S. bovis. For endocarditis caused by enterococci (e.g., E. faecalis), vancomycin has been reported to be effective only in combination with an aminoglycoside. Vancomycin has been reported to be effective for the treatment of diphtheroid endocarditis. Vancomycin has been used successfully in combination with either rifampin, an aminoglycoside, or both in early-onset prosthetic valve endocarditis caused by S. epidermidis or diphtheroids. Specimens for bacteriologic cultures should be obtained in order to isolate and identify causative organisms and to determine their susceptibilities to vancomycin. To reduce the development of resistant bacteria and maintain the effectiveness of vancomycin and other antibacterials, vancomycin should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria. When culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy. In the absence of such data, local epidemiology and susceptibility patterns may contribute to the empiric selection of therapy. VANCOMYCIN Mechanism of Action Vancomycin is an antibiotic which is structurally classified as a glycopeptide. It mainly acts by prevention of cell-wall biosynthesis of bacteria. It is specially effective against gram-positive bacteria and has been known to be effective against resistant strains of MRSA. Vancomycin is known as the antibiotic of last resort as it generally used when all other treatments have failed. However, bacteria have started developing resistance to vancomycin as well- leading to use of other antibiotics. Vancomycin acts by inhibiting cell wall synthesis of bacteria. Peptidoglycan layer of the cell wall is rigid due to its highly cross-linked structure. During the synthesis of the peptidoglycan layer of bacteria, new building blocks of peptidoglycan get inserted (i.e. monomers of N-acetylmuramic acid and N-acetylglucosamine) into the membrane.Vancomycin inhibit the synthesis of bacterial cell wall phospholipids as well as peptidoglycan polymerization in a time dependent fashion by binding to the D-ala-D-ala side chain of the precursor pentapeptide.This prevent the transglycosylation step in peptidoglycan polymerization . By doing so, vancomycin makes the peptidoglycan layer less rigid and more permeable. This causes cellular contents of the bacteria to leak out and eventually death of the bacteria. Mutations in the transpeptidase enzyme can lead to increased resistance to vancomycin. Adverse Effects more than 10% Bitter taste (PO) Erythematous rash on face and upper body (IV; red neck or red man syndrome; related to infusion rate) Hypotension accompanied by flushing (IV) Nausea and vomiting (PO) 1-10% Chills (IV) Drug fever (IV) Eosinophilia (IV) Rash (IV) Fatique (PO) Peripheral edema (PO) Urinary tract infection (PO) Back pain (PO) Headache (PO) Reversible neutropenia (IV) Phlebitis (IV) less than 1% Nephrotoxicity Ototoxicity (especially with large doses) Stevens-Johnson syndrome Thrombocytopenia Vasculitis
Просмотров: 4176 Medinaz
VANCOMYCIN - What You Need to Know Vancomycin is a bactericidal glycoprotein that binds to the d-Ala-d-Ala terminal of the nascent peptidoglycan pentapeptide side chain and inhibits transglycosylation. Vancomycin is indicated for the treatment of serious or severe infections caused by susceptible strains of methicillin-resistant (beta-lactam-resistant) staphylococci. It is indicated for penicillin-allergic patients, for patients who cannot receive or who have failed to respond to other drugs, including the penicillins or cephalosporins, and for infections caused by vancomycin-susceptible organisms that are resistant to other antimicrobial drugs. Vancomycin is indicated for initial therapy when methicillin-resistant staphylococci are suspected, but after susceptibility data are available, therapy should be adjusted accordingly. Vancomycin is effective in the treatment of staphylococcal endocarditis. Its effectiveness has been documented in other infections due to staphylococci, including septicemia, bone infections, lower respiratory tract infections, skin and skin structure infections. When staphylococcal infections are localized and purulent, antibiotics are used as adjuncts to appropriate surgical measures. Vancomycin has been reported to be effective alone or in combination with an aminoglycoside for endocarditis caused by Streptococcus viridans or S. bovis. For endocarditis caused by enterococci (e.g., E. faecalis), vancomycin has been reported to be effective only in combination with an aminoglycoside. Vancomycin has been reported to be effective for the treatment of diphtheroid endocarditis. Vancomycin has been used successfully in combination with either rifampin, an aminoglycoside, or both in early-onset prosthetic valve endocarditis caused by S. epidermidis or diphtheroids. Specimens for bacteriologic cultures should be obtained in order to isolate and identify causative organisms and to determine their susceptibilities to vancomycin. To reduce the development of drug-resistant bacteria and maintain the effectiveness of vancomycin and other antibacterial drugs, vancomycin should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria. When culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy. In the absence of such data, local epidemiology and susceptibility patterns may contribute to the empiric selection of therapy. VANCOMYCIN Mechanism of Action Vancomycin is an antibiotic drug which is structurally classified as a glycopeptide. It mainly acts by prevention of cell-wall biosynthesis of bacteria. It is specially effective against gram-positive bacteria and has been known to be effective against resistant strains of MRSA. Vancomycin is known as the drug of last resort as it generally used when all other treatments have failed. However, bacteria have started developing resistance to vancomycin as well- leading to use of other antibiotics. Vancomycin acts by inhibiting cell wall synthesis of bacteria. Peptidoglycan layer of the cell wall is rigid due to its highly cross-linked structure. During the synthesis of the peptidoglycan layer of bacteria, new building blocks of peptidoglycan get inserted (i.e. monomers of N-acetylmuramic acid and N-acetylglucosamine) into the membrane.Vancomycin inhibit the synthesis of bacterial cell wall phospholipids as well as peptidoglycan polymerization in a time dependent fashion by binding to the D-ala-D-ala side chain of the precursor pentapeptide.This prevent the transglycosylation step in peptidoglycan polymerization . By doing so, vancomycin makes the peptidoglycan layer less rigid and more permeable. This causes cellular contents of the bacteria to leak out and eventually death of the bacteria. Mutations in the transpeptidase enzyme can lead to increased resistance to vancomycin. Adverse Effects more than 10% Bitter taste (PO) Erythematous rash on face and upper body (IV; red neck or red man syndrome; related to infusion rate) Hypotension accompanied by flushing (IV) Nausea and vomiting (PO) 1-10% Chills (IV) Drug fever (IV) Eosinophilia (IV) Rash (IV) Fatique (PO) Peripheral edema (PO) Urinary tract infection (PO) Back pain (PO) Headache (PO) Reversible neutropenia (IV) Phlebitis (IV) less than 1% Nephrotoxicity Ototoxicity (especially with large doses) Stevens-Johnson syndrome Thrombocytopenia Vasculitis
Просмотров: 13542 Medinaz
Check us out on Facebook for DAILY FREE REVIEW QUESTIONS and updates! (https://www.facebook.com/medschoolmadeeasy) Check out our website for TONS OF FREE REVIEW QUESTIONS! (http://medschoolmadeeasy.com/) Thanks for stopping by, and we love hearing from you! Disclaimer: the information in this video only represents the knowledge and property of the video’s authors- no one else.
Просмотров: 21825 Med School Made Easy
Presentation by Dr. Sanaz Dovell, Dr. Vanessa Rowan, Taylor Anderson, Emily Ruple; Science and Health Care Track The inhibitory effects of twelve essential oils were screened against three gram positive bacteria and three gram negative bacteria using the disk diffusion method. Of the twelve undiluted essential oils screened, five oils were selected for further testing using the broth microdilution method based on their ability to inhibit the bacterial growth for all six of the tested bacteria. To view full research abstract see page 7 in the 2015-2016 Interdisciplinary Research Conference Program.
Просмотров: 3929 Palm Beach Atlantic University
New antibiotics from the microbial dark matter Air date: Wednesday, February 15, 2017, 3:00:00 PM Category: WALS - Wednesday Afternoon Lectures Runtime: 00:58:16 Description: NIH Director's Wednesday Afternoon Lecture Series We are experiencing an antibiotic crisis: Our ability to discover novel compounds has diminished and pathogens go largely unchecked in acquiring and spreading resistance. The main source of antibiotics–soil actinomycetes–has been overmined. In chronic infections, the problem is compounded by the presence of dormant persister cells that are resistant to all antibiotics. As a result, chronic osteomyelitis or infections in patients with cystic fibrosis can be untreatable. About 99 percent of environmental microorganisms are uncultured. Dr. Lewis’s lab developed approaches for killing persister cells and growing uncultured bacteria. The lab found that this "microbial dark matter" harbors novel antimicrobials that evolved to be essentially free of resistance. For more information go to https://oir.nih.gov/wals/2016-2017 Author: Kim Lewis, Ph.D., Director, Antimicrobial Discovery Center, Northeastern University Permanent link: https://videocast.nih.gov/launch.asp?21138
Просмотров: 1550 nihvcast
Contact information: Instagram: https://www.instagram.com/profmohamedsherif/ Facebook: https://www.facebook.com/DoctorMohamedSherif/ LinkedIn: https://eg.linkedin.com/in/mohamedsherif45 Transcribed by Nada Khaled - email: firstname.lastname@example.org
Просмотров: 8681 Dr. Mohamed Sherif Lectures
Hello Viewers !!! My Name Is Kavindu Lakmal , Medical Laboratory Science Student From University Of Peradeniya. I designed this video from my Text books notes & internet resources. I hope this video will helpful for your studies ... Don't Forget to subscribe me ... You can update with more new videos .... Please Comment your ideas about Video .... ****************************** HELP ME !!! *********************** I Love to make this like videos Continuously …. But everything need some money , So your little donation I really appreciate . Your just 1$ donation help to design many more videos … Become a Patron - https://www.patreon.com/user?u=4259366 ******************************************************************** Not Only That , Need To Design this Like Video For You Or Any Video Editing Help ??? Contact me ... email@example.com Skype Name - kavindu.lakmal11 Thank You ************************************************************* Video Script :- Blood Agar Media Blood agar is an enriched media , which capable of growing a range of microorganisms of clinical significance. Fastidious organisms, such as streptococci, do not grow well on ordinary growth media. BUT Blood agar is a type of growth medium that encourages the growth of bacteria, such as streptococci, that otherwise wouldn’t grow. ................................................... Also Blood contains inhibitors , for certain bacteria such as Neisseria and Haemophilus genera and the blood agar must be heated to inactivate these inhibitors and to release essential growth factors such as x factor & V factor . But When Heating of blood agar converts it into chocolate agar and supports the growth of these bacteria. Blood agar can be made selective for certain pathogens , by the addition of antibiotics, chemicals or dyes. Examples includes crystal violet blood agar to select Streptococcus pyogens from throat swabs, and kanamycin or neomycin blood agar , to select anaerobes from pus. Composition Of Blood Agar Blood agar media consist of , Pancreatic digest of casein Papaic digest of soy meal 0.5% NaCl Agar Distilled water & 5% Sheep Blood Combine of the ingredients and final pH should be 7.3 .................................................. Uses Of Blood Agar Media There 3 main uses of Blood agar , they are Isolation organisms Identification & Detect antimicrobial susceptibility. After spreading specimen on blood agar media , can be examine isolated pathogen organisms colonies on blood agar media. So blood agar really important to Isolate medically significant organisms. Also blood agar media gives good colony appearance , hemolysis patterns such as Alpha , Beta & gama & pigment production. Quality control of Blood Agar Using Quality control of blood agar , we can identify whether our media in good quality or not , If not we have to discard all media There several method to Quality control Blood agar , The pH of the blood agar range should from 7.2 to 7.6 at room temperature. Incubate the plates in a carbon dioxide enriched atmosphere at 35-37°C overnight & check there any contamination present or not Check the growth of positive control organisms & see colony , morphology , In this case these positive control organisms must grow on blood agar media & gives identical colony morphology , So Staphylococcus aureus - should give good growth with white coloured colonies Streptococcus pyogenes - should give good growth with pale colonies and beta haemolysis And Streptococcus pneumonia - should give good growth with gray coloured colonies & alpha hemolysis
Просмотров: 10069 Aladdin Creations
**EDIT: More medications than just the 2 I listed can be used to treat hospital-associated MRSA. I was mistaken. However, there are still many more options for community-acquired than hospital-acquired.** Explanation of the concept surrounding the double disk diffusion assay used for clindamycin-sensitive, erythromycin-resistant MRSA.
Просмотров: 298 Catherine Ingram
This video lesson demonstrates the procedure we will use in lab to perform the Bauer-Kirby method of antibiotic susceptibility testing. NOTE: This is an abbreviated version we will use in our lab. The procedure performed in clinical labs is much more standardized and complex.
Просмотров: 5352 Dr. Gary Kaiser
Performance of antibiotic susceptibility testing by disk diffusion method.
Просмотров: 50322 Sridhar Rao
http://preventdisease.com/news/11/041311_manuka_honey_benefits.shtml Manuka Honey Reverses Antibiotic Resistance, Treats Disease Manuka honey could be an efficient way to clear chronically infected wounds and could even help reverse bacterial resistance to antibiotics, according to research presented at the Society for General Microbiology's Spring Conference in Harrogate. Professor Rose Cooper from the University of Wales Institute Cardiff is looking at how manuka honey interacts with three types of bacteria that commonly infest wounds: Pseudomonas aeruginosa, Group A Streptococci and Meticillin-resistant Staphylococcus aureus (MRSA). Her group has found that honey can interfere with the growth of these bacteria in a variety of ways and suggests that honey is an attractive option for the treatment of drug-resistant wound infections. Honey has long been acknowledged for its antimicrobial properties. Traditional remedies containing honey were used in the topical treatment of wounds by diverse ancient civilisations. Manuka honey is derived from nectar collected by honey bees foraging on the manuka tree in New Zealand and is included in modern licensed wound-care products around the world. However, the antimicrobial properties of honey have not been fully exploited by modern medicine as its exact mechanisms of action are not yet known. Studies on the Manuka Honey benefits have shown that Manuka Honey, a special type of mono-floral honey contains an ingredient with powerful antibacterial, anti microbial, antiviral, antioxidant, antiseptic, anti-inflammatory and anti fungal properties. This ingredient was originally named UMF®. One of the first scientists to study the benefits of Manuka Honey is Associate Professor in Biochemistry, Peter Molan from the University of Waikato in Hamilton, New Zealand. He began to research the Manuka Honey benefits since 1981 when he discovered that some samples of Manuka Honey contain a non-peroxide component. Tests conducted proved that after adding a catalase to the samples of Manuka Honey in order to remove the hydrogen peroxide, some samples still had a significant antibacterial activity. Dr. Peter Molan named this non-peroxide element UMF®, Unique Manuka Factor. Professor Cooper's group is helping to solve this problem by investigating at a molecular level the ways in which manuka honey inhibits wound-infecting bacteria. "Our findings with streptococci and pseudomonads suggest that manuka honey can hamper the attachment of bacteria to tissues which is an essential step in the initiation of acute infections. Inhibiting attachment also blocks the formation of biofilms, which can protect bacteria from antibiotics and allow them to cause persistent infections," explained Professor Cooper. "Other work in our lab has shown that honey can make MRSA more sensitive to antibiotics such as oxacillin -- effectively reversing antibiotic resistance. This indicates that existing antibiotics may be more effective against drug-resistant infections if used in combination with manuka honey." This research may increase the clinical use of manuka honey as doctors are faced with the threat of diminishingly effective antimicrobial options. "We need innovative and effective ways of controlling wound infections that are unlikely to contribute to increased antimicrobial resistance. We have already demonstrated that manuka honey is not likely to select for honey-resistant bacteria," said Professor Cooper. At present, most antimicrobial interventions for patients are with systemic antibiotics. "The use of a topical agent to eradicate bacteria from wounds is potentially cheaper and may well improve antibiotic therapy in the future. This will help reduce the transmission of antibiotic-resistant bacteria from colonised wounds to susceptible patients."
Просмотров: 267 Natural Remedies
This video “Cell Wall Synthesis Inhibitors: Antibiotics” is part of the Lecturio course “Antimicrobial Pharmacology” ► WATCH the complete course on http://lectur.io/42 ► LEARN ABOUT: - Overview of cell wall synthesis - Antibacterial agents - Cell wall synthesis inhibitors ► THE PROF: Dr. Shukle is a board certified specialist in internal medicine. He performs over 150 special lectures across the nation each year with various audiences ranging from the general public, to nurses, to physicians, to medical specialists. His lectures are engaging, funny, and informative. ► LECTURIO is your single-point resource for medical school: Study for your classes, USMLE Step 1, USMLE Step 2, MCAT or MBBS with video lectures by world-class professors, recall & USMLE-style questions and textbook articles. Create your free account now: http://lectur.io/42 ► INSTALL our free Lecturio app iTunes Store: https://app.adjust.com/z21zrf Play Store: https://app.adjust.com/b01fak ► READ TEXTBOOK ARTICLES related to this video: Antibiotics – Types and Antibiotic Therapy http://lectur.io/antibioticsarticle ► SUBSCRIBE to our YouTube channel: http://lectur.io/subscribe ► WATCH MORE ON YOUTUBE: http://lectur.io/playlists ► LET’S CONNECT: • Facebook: https://www.facebook.com/lecturio.medical.education.videos • Instagram: https://www.instagram.com/lecturio_medical_videos • Twitter: https://twitter.com/LecturioMed
Просмотров: 3006 Lecturio Medical Education
Part 1 of PD of antibiotics Table of Contents: 00:40 - Individualization 01:30 - Concepts 01:40 - Concepts 01:43 - Concepts 02:16 - Concepts 03:23 - Antimicrobial-micro-organism interaction 04:02 - Static versus Cidal 04:55 - Questions 05:32 - Can this antibiotic inhibit/kill these bacteria? 05:49 - 06:07 - What concentration of this antibiotic is needed to inhibit/kill bacteria? 06:50 - Patterns of Microbial Killing 08:40 - Persistent Effects: Post antibiotic effect 08:48 - Patterns of Microbial Killing 09:00 - Persistent Effects: Post antibiotic effect 10:29 - Persistent Effects 11:14 - Patterns of Antimicrobial Activity 12:27 - Patterns of Antimicrobial Activity 13:14 - Patterns of Antimicrobial Activity 13:31 - PK/PD patterns 14:04 -
Просмотров: 1546 Sandra Earle
Video abstract of original research paper “Silver-loaded nanotubular structures enhanced bactericidal efficiency of antibiotics with synergistic effect in vitro and in vivo” published in the open access journal International Journal of Nanomedicine by Xu et al. Abstract: Antibiotic-resistant bacteria have become a major issue due to the long-term use and abuse of antibiotics in treatments in clinics. The combination therapy of antibiotics and silver (Ag) nanoparticles is an effective way of both enhancing the antibacterial effect and decreasing the usage of antibiotics. Although the method has been proved to be effective in vitro, no in vivo tests have been carried out at present. Herein, we described a combination therapy of local delivery of Ag and systemic antibiotics treatment in vitro in an infection model of rat. Ag nanoparticle-loaded TiO2 nanotube (NT) arrays (Ag-NTs) were fabricated on titanium implants for a customized release of Ag ion. The antibacterial properties of silver combined with antibiotics vancomycin, rifampin, gentamicin, and levofloxacin, respectively, were tested in vitro by minimum inhibitory concentration (MIC) assay, disk diffusion assay, and antibiofilm formation test. Enhanced antibacterial activity of combination therapy was observed for all the chosen bacterial strains, including gram-negative Escherichia coli (ATCC 25922), gram-positive Staphylococcus aureus (ATCC 25923), and methicillin-resistant Staphylococcus aureus (MRSA; ATCC 33591 and ATCC 43300). Moreover, after a relative short (3 weeks) combinational treatment, animal experiments in vivo further proved the synergistic antibacterial effect by X-ray and histological and immunohistochemical analyses. These results demonstrated that the combination of Ag nanoparticles and antibiotics significantly enhanced the antibacterial effect both in vitro and in vivo through the synergistic effect. The strategy is promising for clinical application to reduce the usage of antibiotics and shorten the administration time of implant-associated infection. Read the original article here: https://www.dovepress.com/silver-loaded-nanotubular-structures-enhanced-bactericidal-efficiency--peer-reviewed-article-IJN
Просмотров: 306 Dove Medical Press
TRINITY V3 Microbiology System color digital imaging automates zone reading and analysis for antibiotic potency assays. An optional colony counting application is available. This complete industrial microbiology system is ideal for Quality Assurance and Quality Control testing in pharmaceutical, food and feed microbiology laboratories. TRINITY V3 strictly complies with 21 CFR Part 11 electronic signature requirements from reading test plates to reporting test results. TRINITY V3 software follows USP, EP, BP and JP agar diffusion assay methods. IQ OQ PQ validation documents are included with each system purchase. TRINITY V3 is designed and manufactured by Giles Scientific in California, USA.
Просмотров: 2431 GilesScientific
A group of UTAR foundation students (Dharsan Ram, Chin Yaw Yong & Tan Chun Teck) has conducted a Biology mini project to learn and develop some practical skills.
Просмотров: 716 Ngai Suet Loo
A review around some of the issues related to gram negative susceptibility testing. Recorded in 2010.
Просмотров: 644 IDPodcasts
U.S. scientists have discovered a new class of antibiotic that can kill many kinds of drug-resistant pathogens, according to a report published Wednesday in the journal Nature. Many pathogens have evolved to resist antibiotics developed from bacteria that can be grown in labs. So the scientists developed the new drug, known as Teixobactin, by screening 10,000 bacterial strains from soil that cannot be cultured in labs. To grow germs from soil bacteria, scientists filled a device containing several hundred dotted chambers with cells from different bacterium. The device, which they call the iChip, was then placed in soil to allow the bacteria to grow. Once the bacteria were cultivated, they were placed in a petri dish and covered by a target bacteria, called Staph. Empty zones in the petri dish signalled that the bacteria below had released an antibiotic that inhibited the growth of the target Staph bacteria. The newly discovered antibiotic, Teixobactin, kills a class of bacteria called gram-positive bacteria by binding to the building blocks they use to construct their cell walls and causing the cell walls to break down. It is especially effective against bacteria that cause certain types of tuberculosis and pneumonia, and Staphylococcus aureus, which causes MRSA. Teixobactin, however, does not work against gram-negative bacteria, including bacteria that cause cholera and gonorrhea. Kim Lewis, a professor at Northeastern University in Boston and lead author of the study, told the Wall Street Journal that there could be human trials of Teixobactin in two years. He said the trials could take two to three years. ------------------------------------------------------------- Welcome to TomoUSA, where we animate the most entertaining news from ‘MURRICA. Grab your guns and fried Oreos, and sit back to watch all the craziest headlines. USA! USA! USA! Subscribe for viral news from the land of the free: https://www.youtube.com/subscription_center?add_user=TomoNewsUSA Visit our official website for all the latest, uncensored videos: https://us.tomonews.net Check out our Android app: http://bit.ly/1rddhCj Check out our iOS app: http://bit.ly/1gO3z1f Stay connected with us here: Facebook http://www.facebook.com/TomoNewsUS Twitter @tomonewsus http://www.twitter.com/TomoNewsUS Google+ http://plus.google.com/+TomoNewsUS/ Instagram @tomonewsus http://instagram.com/tomonewsus
Просмотров: 906 TomoUSA
A time-lapse of the Kirby-bauer test done with E. coli and S. aureus. The Kirby-Bauer test uses Mueller-Hinton agar to test a bacterium's susceptibility to antibiotics by using discs that have antibiotics in it. Antibiotics can work in one of two ways: they either slow down growth (bacteriostatic) or kill the bacteria (Bactericidal). A lot of antibiotics target the thick peptidoglycan layer of the cell wall in gram positive organisms, which makes gram negative bacteria more resistant to these antibiotics. If the bacteria is susceptible to the antibiotic, it will create a zone of inhibition which is the area around the antibiotic disc where the bacteria did not grow. A larger zone indicates greater susceptibility. Cultures were grown at approximately 37 degrees Celsius. الاوساط الزرعية البكتريا اهم انواع البكتريا اللوان البكتريا علم البكتريا Bacteria بكتريولوجي عالم المختبرات والتحاليل الطبية تحاليل طبية تحاليل مختبرية كل ما يخص البكتريا هل تعلم تصبيغ البكتريا Cultivation circles Bacteria The most important types of bacteria Color of bacteria Bacteriology Bacteria Bacteriology The world of laboratory and medical analysis Medical analysis Laboratory analysis All about bacteria Did you know Pigmentation of bacteria
Просмотров: 70 العقل العربي Arab Mind
Peter L. Salgo, MD; Jason Pogue, PharmD, BCPS-AQID; and Andrew Shorr, MD, discuss the recent approval of Vabomere, a combination of meropenem and vaborbactam, in the setting of gram-negative nosocomial infections based on the positive study results of the TANGO II trial.
Просмотров: 295 Contagion_Live
This video discusses the cell wall structures of both Gram + and - bacteria with practice questions
Просмотров: 230054 Withbothmyeyes
Video abstract of original research paper “Identification of Mycobacterium tuberculosis BioA inhibitors by using structure-based virtual screening” published in the open access journal Drug Design, Development and Therapy by authors Singh, Khare, Bahal, et al. Background: 7,8-Diaminopelargonic acid synthase (BioA), an enzyme of biotin biosynthesis pathway, is a well-known promising target for anti-tubercular drug development. Methods: In this study, structure-based virtual screening was employed against the active site of BioA to identify new chemical entities for BioA inhibition and top ranking compounds were evaluated for their ability to inhibit BioA enzymatic activity. Results: Seven compounds inhibited BioA enzymatic activity by greater than 60% at 100 μg/mL with most potent compounds being A36, A35 and A65, displaying IC50 values of 10.48 μg/mL (28.94 μM), 33.36 μg/mL (88.16 μM) and 39.17 μg/mL (114.42 μM), respectively. Compounds A65 and A35 inhibited Mycobacterium tuberculosis (M. tuberculosis) growth with MIC90 of 20 μg/mL and 80 μg/mL, respectively, whereas compound A36 exhibited relatively weak inhibition of M. tuberculosis growth (83% inhibition at 200 μg/mL). Compound A65 emerged as the most potent compound identified in our study that inhibited BioA enzymatic activity and growth of the pathogen and possessed drug-like properties. Conclusion: Our study has identified a few hit molecules against M. tuberculosis BioA that can act as potential candidates for further development of potent anti-tubercular therapeutic agents. Read the original research paper here: https://www.dovepress.com/identification-of-mycobacterium-tuberculosis-bioa-inhibitors-by-using--peer-reviewed-article-DDDT
Просмотров: 159 Dove Medical Press
This video is meant to act as an index for topics from the FIRST AID for the USMLE STEP 1 (2016). If you find any errors or broken links, leave me a comment! Good luck in school!! Topic list: • Antimicrobial Therapy • Penicillin G, V • Penicillinase-sensitive Penicillins • Penicillinase-resistant Penicillins • Antipseudomonal Penicillins • B-Lactamase Inhibitors • Cephalosporins • Carbapenems • Monobactams • Vancomycin • Protein Synthesis Inhibitors • Aminoglycosides • Tetracyclines • Chloramphenicol • Clindamycin • Oxazolidinones • Macrolides • Sulfonamides • Dapsone • Trimethoprim • Fluoroquinolones • Daptomycin • Metronidazole • Antimycobacterial Drugs • Rifamycins • Isoniazid • Pyrazinamide • Ethambutol • Streptomycin • Antimicrobial Prophylaxis • Prophylaxis in HIV Patients • Treatment of Highly Resistant Bacteria • Antifungal Therapy • Amphotericin B • Nystatin • Flucytosine • Azoles • Terbinafine • Echinocandins • Griseofulvin • Antiprotozoan Therapy • Anti-mite Anti-louse Therapy • Chloroquine • Antihelminthic Therapy • Antiviral Therapy • Oseltamivir Zanamivir • Acyclovir Famciclovir Valacyclovir • Ganciclovir • Foscarnet • Cidofovir • HIV Therapy • Interferons • Hepatitis C Therapy • Infection Control Techniques • Antimicrobials to Avoid in Pregnancy Hey guys and gals, I am constantly trying to find better videos for you to study from (it’s not easy)! You can help by suggesting any good videos you see in the comments below! Good luck in school!! -~-~~-~~~-~~-~- Please watch: "Understand the Arterial Blood Gas " https://www.youtube.com/watch?v=1TnykLis7nA -~-~~-~~~-~~-~-
Просмотров: 790 Med Immersion
ABSTRACT Background: Allium sativum, commonly known as garlic, exhibits antibacterial effects against a wide range of bacteria. Aim: The objective of this in vitro study was to evaluate the inhibitory effect of garlic extract Against 12 types of bacteria, including 4 isolates of gram-positive (Streptococcus, Streptococcus MDR, staphylococcus, staphylococcus MDR), and 8 isolates of gram-negative (Acinetobacter MDR , Pseudomonas, Pseudomonas MDR, Escherichia, Escherichia MDR, klebsiella, klebsiella MDR, klebsiella pneumonia ). And assess the antibacterial effect of different concentrations of garlic extract against these bacteria by dilution method. Materials and Methods: Antibacterial activities of garlic extract (sensitivity test) by using agar well Diffusion of extract on the surface of MHA medium seeded with the test organisms, and using five different concentrations of garlic extract (20%, 40%,60%,80%, and 100%) were evaluated against (Streptococcus, Streptococcus MDR, staphylococcus, staphylococcus MDR, Acinetobacter MDR , Pseudomonas, Pseudomonas MDR, Escherichia, Escherichia MDR, klebsiella, klebsiella MDR, klebsiella pneumonia ). Results: All bacterial strains were inhibited by diffusion extract method, the inhibition zones of the different type of bacteria were Varying, and the growth in five different concentrations of garlic extract (20%, 40%, 60%, 80%, and 100%) were not significantly different from one to another.
Просмотров: 1940 Osama ALAloul
Approved drugs containing thiols as inhibitors of Metallo-β-Lactamases Antibiotic resistance in bacterial pathogens is one of the major threats regarding human health. An alarming trend is the spread of metallo-β-lactamases (MBLs) among gram-negative pathogens that transfer resistance against almost all β-lactam antibiotics including carbapenems. The development of new anti-infective agents remains one of the most significant demands in modern medicine. In this webinar we show the development of an assay platform consisting of three orthogonal assays: a fluorescence-based functional assay, thermal shift assay and in cell antimicrobial susceptibility testing. The reliability of the system was evaluated on three different class B MBLs: New-Delhi-Metallo-β-Lactamase-1 (NDM-1), Verona-Integron-Encoded-Metallo-β-Lactamase 1 (VIM-1) and Impenemase-7 (IMP-7). The aim of this work is to find an already approved drug which restores the activity of β-lactam antibiotic by protecting it from hydrolysis through the MBL. We could find four drugs, which inhibit three clinically important MBLs, namely Captopril, Thiorphan, Dimercaprol and Tiopronin. This is a good starting point for the development of potent MBL inhibitors, with the primary optimization goal being the uptake and activity in pathogens. This will be modeled in SeeSAR. http://www.biosolveit.de/SeeSAR
Просмотров: 384 BioSolveITTutorials
Haemophilus resistant towards 10 microgram disc where as generally other bacteria sensitive and thus colonies are screened for Haemophilus but also smelling, colonies type, oxidase test are important. In reference to Streptococcus pneumoniae, 5 micro gram optochin disc inhibits growth of pneumococcus and hence organism is sensitive but zone of inhibition should be equal and greater than 14mm that is not applicable in viridans streptococci. -~-~~-~~~-~~-~- Please watch: "Germ tube test" https://www.youtube.com/watch?v=W-fSMpaRA2o -~-~~-~~~-~~-~-
Просмотров: 156 Microhub Plus
I begin the video by talking about the Kirby-Bauer disk test a common microbiology lab exercise. Then I go on to explain in more detail how Penicillin works, and how the sulfa drugs work to inhibit metabolic intermediates.
Просмотров: 2049 FortuneFavorsPrep
I discussed the Microbiological assay of antibiotics with Diagrams, Methods employed, and the procedure with diagrams Find me: 👍 Facebook: https://www.facebook.com/Centreoflearning1/ 📷 Instagram: https://www.instagram.com/centre_of_learning/ 🐥 Twitter: https://twitter.com/Free_Pptx 🌹 https://www.youtube.com/channel/UCcnCVaeAefh8SZ1ZDa2q9Tw?sub_confirmation=1 Please like and subscribe and keep in touch for every new presentation. Thanks for the support
Просмотров: 4283 Centre of Learning
What Are Antibotics,https://goo.gl/r1938O Testing the susceptibility ofStaphylococcus aureus to antibiotics by the Kirby-Bauer disk diffusion method – antibiotics diffuse from antibiotic-containing disks and inhibit growth of S. aureus, resulting in a zone of inhibition. Antibiotics or antibacterials are a type of antimicrobial used in the treatment and prevention of bacterial infection. They may either kill or inhibit the growth of bacteria. Several antibiotics are also effective against fungi and protozoans, and some are toxic to humans and animals, even when given in therapeutic dosage. Antibiotics are not effective against viruses such as the common cold or influenza, and may be harmful when taken inappropriately. In 1928, Alexander Fleming identified penicillin, the first chemical compound with antibiotic properties. Fleming was working on a culture of disease-causing bacteria when he noticed the spores of little green mold in one of his culture plates. He observed that the presence of the mold killed or prevented the growth of the bacteria. Antibiotics revolutionized medicine in the 20th century, and have together with vaccination led to the near eradication of diseases such astuberculosis in the developed world. Their effectiveness and easy access led to overuse, especially in livestock raising, prompting bacteria to develop resistance. This has led to widespread problems with antimicrobial and antibiotic resistance, so much as to prompt the World Health Organization to classify antimicrobial resistance as a "serious threat [that] is no longer a prediction for the future, it is happening right now in every region of the world and has the potential to affect anyone, of any age, in any country". The era of antibacterial chemotherapy began with the discovery of arsphenamine, first synthesized by Alfred Bertheim and Paul Ehrlich in 1907, used to treat syphilis. The first systemically active antibacterial drug, prontosil was discovered in 1933 by Gerhard Domagk, for which he was awarded the 1939 Nobel Prize. All classes of antibiotics in use today were first discovered prior to the mid 1980s. Sometimes the term antibiotic is used to refer to any substance used against microbes, synonymous to antimicrobial, leading to the widespread but incorrect belief that antibiotics can be used against viruses. Some sources distinguish between antibacterial and antibiotic; antibacterials used in soaps and cleaners etc., but not as medicine.This article treats the terms as synonymous and according to the most widespread definition of antibiotics being a substance used against bacteria. Pharmacodynamics thank you https://goo.gl/r1938O
Просмотров: 35 Tips digital1
Here is the 2nd part of the "at home penicillium" culture test. I took varying amounts of liquid culture broth and put them on cut filter paper on nutriet agar plates that were covered with B. subtilis. I plated 4 experimental dishes vs one control dish with two 10 unit discs of penicillin. B. subtilis is a gram positive bacteria, and so should respond to pencillin. Unfortunately, I wasn't able to check the plates until 3 days after the initial plating, so I saw no rings of inhibition. I will update a blog post of the event soon and final pictures at www.basementbiotech.org
Просмотров: 6767 BasementBiotech
This is a short video on three intracellular bacteria that infect the lungs. I created this presentation with Google Slides. Image were created or taken from Wikimedia Commons I created this video with the YouTube Video Editor. ADDITIONAL TAGS: Species Replication Location Membrane/ Wall Stain Epidemiology Transmission Immune Response/ Pathogenesis/Pathology Diagnosis Treatment/Vaccine Associated Mycobacterium tuberculosis Intracellular (facultative); macrophages ACID-FAST stain for mycolic acid (thick, waxy coat) HIV (and other immunosuppressed) are major risk factor Aerosol droplet nuclei (requires airborne precautions) Chronic pneumonia; chest cold symptoms + hemotysis, night sweats, weight loss, caused by immune host response primary -- latent -- reactivated stages; latent to reactive caused by immunosuppression or reinfection Infection controlled by CD4 and CD8 T cells (triggered by IFN-gamma) and macrophages -- granuloma formation HIV people get miliary TB; Diagnosed with PPD skin test (has problems HIV+ and BCG vaccine), sputum culture, QuantiFERON Test for IFN-gamma, Xpert MTB/RIF PCR test First line abx are RIPE (rifampin, isoniazid, pyrazinamide, ethambutol) BCG vaccine from bovine TB (M bovis), variable efficacy Mycobacterium leprae causes leprosy Atypical Mycobacteria / Non-Tuberculosis Mycobacteria (NTM) - not spread person to person Legionella pneumophila Intracellular (facultative); survives in humans (macrophages) and environment (amoeba) Gram negative Opportunistic; risk factors are age (50+), smoking, COPD, immunosuppression Inhalation of contaminated water (not spread person- to- person) Acute pneumonia; Legionnairesâ€™ disease Hard to diagnose, stains poorly; grow culture on specialized agar Treat with macrolides (50S inhibitors, ie clarithromycin, azithromycin) Same bug causes Pontiac fever (more flu-like symptoms, not pneumonia) Chlamydia pneumoniae Intracellular (obligate); macrophages and epithelial cells Gram negative High rate of carriers wo symptoms Repsiratory droplets, larger than droplet nuclei, (requires droplet precautions) Chronic "walking" pneumonia Lifecycle has two stages: (1) elementary bodies, infectious but no metabolism and (2) reticulate bodies, metabolism but not infectious Modified phagosomal membrane called inclusion body Hard to diagnose, lack of std tests, resembles MTB Treat with doxycycline (30S inhibitor) bc it accumulates in host cells C. trachomatis (STD) and C. psittaci (zoonotic) INTRACELLULAR BACTERIA THAT INFECT THE LUNGS
Просмотров: 1206 MedLecturesMadeEasy
This illustration video is about Pseudomonas aeruginosa. This part discusses prevention and treatment. Very use full, beautiful and highly comprehensive illustration with a lot of high yield facts and figures. Treatment Many P. aeruginosa isolates are resistant to a large range of antibiotics and may demonstrate additional resistance after unsuccessful treatment. It should usually be possible to guide treatment according to laboratory sensitivities, rather than choosing an antibiotic empirically. If antibiotics are started empirically, then every effort should be made to obtain cultures (before administering first dose of antibiotic), and the choice of antibiotic used should be reviewed when the culture results are available. The antibiogram of P. aeruginosaon Mueller-Hinton agar Due to widespread resistance to many common first-line antibiotics,carbapenems, polymyxins, and more recentlytigecycline were considered to be the drugs of choice; however, resistance to these drugs has also been reported. Despite this, they are still being used in areas where resistance has not yet been reported. Use of β-lactamase inhibitors such as sulbactam has been advised in combination with antibiotics to enhance antimicrobial action even in the presence of a certain level of resistance. Combination therapy after rigorous antimicrobial susceptibility testing has been found to be the best course of action in the treatment of multidrug-resistant P. aeruginosa. Some next-generation antibiotics that are reported as being active against P. aeruginosa include doripenem, ceftobiprole, and ceftaroline. However, these require more clinical trials for standardization. Therefore, research for the discovery of new antibiotics and drugs against P. aeruginosa is very much needed. Antibiotics that may have activity against P. aeruginosa include: • aminoglycosides (gentamicin, amikacin, tobramycin, but notkanamycin) • quinolones (ciprofloxacin, levofloxacin, but not moxifloxacin) • cephalosporins (ceftazidime, cefepime, cefoperazone, cefpirome,ceftobiprole, but not cefuroxime, cefotaxime, or ceftriaxone) • antipseudomonal penicillins: carboxypenicillins (carbenicillin andticarcillin), and ureidopenicillins (mezlocillin, azlocillin, andpiperacillin). P. aeruginosa is intrinsically resistant to all otherpenicillins. • carbapenems (meropenem, imipenem, doripenem, but notertapenem) • polymyxins (polymyxin B and colistin) • monobactams (aztreonam) As fluoroquinolone is one of the few antibiotics widely effective against P. aeruginosa, in some hospitals, its use is severely restricted to avoid the development of resistant strains. On the rare occasions where infection is superficial and limited (for example, ear infections or nail infections), topical gentamicin or colistin may be used.
Просмотров: 5185 Medical Video Illustration