Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
151 Cards in this Set
- Front
- Back
|
Why anti-infective agents are not as highly profitable as therapies for chronic disorders (e.g. anti-depressants)
|
Antibiotics are not taken for as long
|
|
|
Species of bacteria which can grow in the stomach
|
Helicobacter pylori
|
|
|
allochthonous
|
Originating in a place other than where it is found.
|
|
|
autochthonous
|
Native to the place where found; indigenous.
|
|
|
Early colonising bacteria of the human gut
|
Bifidobacteria
|
|
|
Late colonising bacteria of the human gut
|
Bacteroides
Firmicutes: Faecalibacterium, Clostridia spp. dominate |
|
|
Benefits of being colonised by bacteria
|
Energy
Nutrients Colonisation resistance Development of the gut architecture Immunomodulation |
|
|
Molecular methods for identifying and enumerating bacterial species in a microbiota
|
PCR - polymerase chain reaction
FISH - Fluorescent in situ hybridization |
|
|
Butyric acid
|
A short chain fatty acid converted from polysaccharides by anaerobic bacteria which is readily metabolised as an energy source in the colon
|
|
|
Vitamins released from the diet by the metabolism of intestinal microbiota
|
Vitamin B7 (Biotin)
Vitamin K |
|
|
germ-free impact on gut architecture of mice
|
reduction in villus height
shallower crypt of Lieberkühn |
|
|
Enzyme used by Helicobacter pylori to neutralise stomach acid
|
Urease
|
|
|
term for the presence of toxins in the blood
|
Toxaemia
|
|
|
Pathogen which invades M cells found in the small intestines leading to systemic infection
|
Salmonella typhi
|
|
|
Pathogen responsible for causing cholera
|
Vibrio cholerae
|
|
|
The major types of inflammatory bowel disease
|
Crohn's disease and ulcerative colitis
|
|
|
Commensal
|
An organism that lives in close association with a host, but
causes no harm |
|
|
Symbiont
|
An organism that lives in close association with a host and both
the host and symbiont benefit from this association |
|
|
Pathogen
|
An organism that lives in close association with a host and can
cause disease |
|
|
Opportunistic pathogen
|
An organism that lives in close association with a host and
causes disease in exceptional circumstances, such as when the host has impaired immunity |
|
|
Major sites of microbial colonisation on humans
|
The intestines (very large populations of microbes – increases in number from the proximal to distal end)
Oral cavity Female reproductive tract Skin – not one environment but many (e.g. Dry surface of the back of your hands vs. Underarms) Hair and nails – keratin, non- living |
|
|
Number of bacteria found in the jejunum
|
10^5 cfu/g
|
|
|
Number of bacteria found in the colon
|
10^12 cfu/g
|
|
|
Number of microbes found in moist areas of the skin such as
the armpits |
10^7 cfu/cm^2
|
|
|
Number of microbes found in drier areas of the skin such as the forearms and trunk
|
10^2 cfu/cm^2
|
|
|
Sources of nutrition for microbes on the skin
|
Sweat
Sebum Keratin Make up |
|
|
Most ‘commensal’ flora on human skin are (gram positive? or negative?) and why?
|
Gram positive – slightly more
resistant to salt and to drying out |
|
|
Properties of the microbial environment on the surface of human skin
|
Dry
high salt low pH low nutrients |
|
|
Methods of respiration used by microbes which grow on the surface of human skin, and an example of a microbe found on the surface of the skin
|
Aerobic and facultative anaerobic
e.g. Staphylococcus epidermidis |
|
|
Properties of the microbial environment in a sebaceous gland
|
Innate immune defences
low oxygen, high nutrients. |
|
|
Methods of respiration used by microbes which grow in sebaceous glands, and an example of a microbe found in sebaceous glands
|
Anaerobic and facultative anaerobic
e.g. Propionibacterium acnes |
|
|
moiety
|
Specific groups of atoms within molecules that are responsible for the characteristic chemical reactions of those molecules. Also called a functional group
|
|
|
Cells constituting 95% of human epidermis
|
Keratinocytes
|
|
|
Moieties on or in microbes which are detected by Pattern Recognition Receptors (PRR's)
|
PAMPS
Pathogen Associated Molecular Patterns |
|
|
Examples of PAMPS
|
Components of bacterial cell walls (e.g. LPS, peptidoglycan, and lipoarabinomannan),
Fungal cell wall components (zymosan), Bacterial CpGDNA, Viral RNA Protein subunit of bacterial flagella (flagellin) |
|
|
Colonisation resistance
|
The presence of harmless (under normal circumstances) microbes can prevent the colonisation by pathogens
–Competition for scarce resources –Production of bacteriocins |
|
|
Name prefix given to fungal diseases of the skin
|
Tinea...
Tineapedis– Athlete’s foot Tineacapitis– Fungal infection of the scalp Tineacorporis– Ringworm |
|
|
Fungal species that can cause sub-dermal infection
|
dermatophytes
|
|
|
Fungal infection of the nail
|
Onychomycosis
|
|
|
fungus commonly responsible for athlete's foot , jock itch and ringworm
|
Trichophyton rubrum
|
|
|
Species of fungus responsible for Thrush (Candidiasis)
|
Candida albicans
|
|
|
Microorganisms that inhabit the intestines
|
enteric bacteria
|
|
|
Microbes responsible for urinary tract infections
|
E. coli
Enterococcus faecalis |
|
|
Most abundant genus of bacteria in the reproductive tract of healthy women
|
Lactobacillus
|
|
|
How biofilm forming Lactobacilli prevent harmful microbial colonisation in the female reproductive tract
|
lower the pH to <5
produce a biosurfactant which has been shown to inhibit the binding of opportunistic pathogens |
|
|
The two cellular morphologies of Candida albicans (the cause of thrush / candidiasis)
|
Yeast like – unicellular, division by budding
Hyphal - multicellular |
|
|
Common bacteria found in oral cavities
|
Streptococci:
S. salivarius, S. mutans, S. sanguis, S. pneumoniae |
|
|
Common bacteria found in nasal cavities
|
Gram positive cocci:
Staphylococcus aureus Staphylococcus epidermidis Streptococcus pneumoniae |
|
|
The microbial agent associated with Lyme disease
|
Borrelia burdorferi
|
|
|
Morphological classification of Borrelia burdorferi
|
Gram-negative spirochaete
|
|
|
Common vector of Borrelia burdorferi
|
Ticks
|
|
|
Classical early symptom of Lyme disease
|
Bullseye rash
(Erythema migrans) |
|
|
Species of bacteria commonly responsible for Tuberculosis
|
Mycobacterium tuberculosis
|
|
|
Medium used to culture Mycobacterium
e.g. Mycobacterium tuberculosis |
Löwenstein-Jensen medium
|
|
|
Duration needed to culture Mycobacterium tuberculosis
|
3 - 4 weeks
|
|
|
Sites of tuberculosis infection
|
Lungs - pulmonary TB
Intestines - Intestinal TB Bones - Osseous TB |
|
|
Examples of Mycobacterium
|
Mycobacterium tuberculosis
Mycobacterium Leprae (causes leprosy) |
|
|
Staining method for Mycobacterium and why
|
Acid fast
Mycobacterium have a waxy coat of mycolic acid which make them resistant to gram staining |
|
|
A vaccine for tuberculosis
|
BCG - Bacillus of Calmette and Guerin
|
|
|
Treatment of Tuberculosis
|
Antibiotics: rifampicin & isoniazid
slow growing pathogen = 1 year treatment rising antibiotic resistance |
|
|
# cases of TB in the UK in 2006
|
~8500
|
|
|
# cases of TB in the world in 2006
|
14.4 million
|
|
|
# deaths from TB in the world in 2006
|
1.7 million
|
|
|
Examples of GREEN biotech
|
Food biotech:
Brewing, Baking, Pickling, Crop selection, GMO crops |
|
|
Examples of WHITE biotech
|
Industrial biotech:
Bioethanol, Biobutanol, Detergent enzymes |
|
|
Examples of RED biotech
|
Medical biotech:
Vaccination, Antibiotics, Immunodiagnostics, Phage therapy, Gene therapy |
|
|
Examples of BLUE biotech
|
Aquatic biotech:
Bioluminescence, Aquaculture, Environmental bioremediation |
|
|
Examples of biotech which utilise the whole organism
|
Phage therapy,
Probiotics, Leeches, Maggot debridement therapy |
|
|
Example of biotech which utilise metabolism to clean an environment from contaminants
|
Bioremediation
|
|
|
Examples of biotech which utilise metabolism to produce a desired chemical reaction
|
Brewing
Pickling Bioethanol Biobutanol |
|
|
Examples of biotech which concern nucleic acids
|
Diagnostics
Surveillance Epidemiology Cloning Gene therapy |
|
|
Examples of biotech which concern amino acids
|
Serum therapy
Immunodiagnostics Antibiotics Antimicrobial peptides |
|
|
Advantages of crop selection
|
Higher yields
resistance to pests, diseases and/or drought |
|
|
health benefits of pickling food
|
Prevents spoilage
|
|
|
health benefits of brewing alcoholic beverages
|
The low alcohol content in wine and beer and the organic acids derived from hops in beer and have some antimicrobial properties. In the Cholera outbreak in London of 1854 Dr John Snow discovered a source of the ‘contagion’ at the Broad Street Well – workers at a nearby brewery were unaffected
|
|
|
Ingredients of beer
|
Grain (barley, wheat or rye)
Water Yeast |
|
|
Ingredients of wine
|
Grapes
Natural yeasts Added yeast 'Malolactic' bacteria |
|
|
Semi dwarf wheat
|
Wheat bred by Norman Borlaug to have short stems
|
|
|
The Haber process
|
Synthetic production of ammonia from air
|
|
|
DDT (Dichloro-Diphenyl-Trichloroethane)
|
A widely banned synthetic pesticide
|
|
|
Traits introduced by genetic modification of crops
|
Resistance to insect pests
Resistance to herbicides e.g. Roundup Ready Increased nutritional value Decreased unhealthy traits Edible vaccines Nutriceuticals |
|
|
Bacterial species from which cry toxins are extracted
|
Bacillus thuringiensis
|
|
|
How cry toxins are activated
|
Activated by the alkali in insect digestive tracts
|
|
|
How cry toxins kill insects
|
Forms pores in insect cell membranes which causes them to swell and burst
|
|
|
Crops which cry genes have been cloned in to
|
Cotton
Corn |
|
|
2 advantages in cloning cry genes in to crops
|
Resistant to pests
-Less pesticide needed -less pollution Only effects insects that feed on the crop |
|
|
Disadvantages of cloning cry genes in to crops
|
£ research & development
promotes monocultures -decreased biodiversity Driven by commercial interests Risk of toxin genes spreading to other plants? Contaminates soil |
|
|
White biotechnology
|
industrial biotechnology
(biotechnology applied to industrial processes) |
|
|
Green biotechnology
|
biotechnology applied to agricultural processes
|
|
|
Red biotechnology
|
biotechnology applied to medical
processes |
|
|
Blue biotechnology
|
marine and aquatic applications of
biotechnology |
|
|
Grey biotechnology
|
environmental biotechnology
Identification and decontamination of harmful products |
|
|
What is a Bioprocess?
|
A commercially useful process that relies on biological material and activities e.g.
microorganisms or enzymes, to prepare, produce or process (e.g. treat or convert) substances, the outcome of which may be a valuable product e.g. chemical or fuel, refinement or degradation. |
|
|
An example of an early bioprocess
|
our early ancestors created simple
fermentation systems to make alcoholic beverages from cereal grains without necessarily understanding the underlying biological processes |
|
|
Advantages of bioprocesses over conventional chemical methods of production
|
usually require lower temperature
lower pressure and pH use renewable resources as raw materials less energy consumption usually less toxic by-products ….. or simply no chemical alternative |
|
|
Food or food products that provide health and medical benefits, including the prevention and treatment of disease
|
Nutraceuticals
combination of the words “nutrition” and “pharmaceutical" |
|
|
Brewers yeast
|
Saccharomyces cerevisiae
|
|
|
Common biological fuels produced by the action of yeast or anaerobic bacteria by fermentation of carbohydrates
|
Ethanol, butanol and propanol
|
|
|
Strictly anaerobic, spore-forming, bacterium isolated from corn in 1912 and ferments carbohydrates into solvents: Acetone, Butanol and Ethanol (ABE)
|
Clostridium acetobutylicum
|
|
|
Bioprospecting
|
Search, discovery, collection and identification of novel microbes for commercial exploitation
|
|
|
Secondary metabolites
|
Compounds created my microbes uninvolved with growth, development, or reproduction
Alkaloids, Drugs, Antibiotics |
|
|
Gene commonly used to identify and classify bacterial phylogenies
|
16S rRNA
|
|
|
Search, discovery, collection and identification of novel microbes for commercial exploitation
|
Bioprospecting
|
|
|
Compounds created my microbes uninvolved with growth, development, or reproduction
Alkaloids, Drugs, Antibiotics |
Secondary metabolites
|
|
|
16S rRNA
|
Ubiquitous and highly conserved bacterial gene
Commonly used to identify and classify bacterial phylogenies |
|
|
Where to look for novel microbes
|
Extreme environments (arid, temperature, pH, salt, black smokers)
Soil, sediments, plants, dead animals |
|
|
"Selective Isolation" technique for culturing novel organisms
|
Design of growth media to encourage or inhibit growth of particular microbes
|
|
|
Low nutrient content media to slow growth of fast growing organisms
|
Oligotrophic media
|
|
|
Use of a device to interact with a sample under a microscope
|
Micromanipulation
|
|
|
Fungus from which Penicillin G was discovered
|
Penicillium chrysogenum
|
|
|
Functional group of the Penicillins
|
β-lactam ring
|
|
|
Chemotherapeutic sulphur drugs
|
Sulphonamides
|
|
|
Derivatives of penicillin
|
Methicillin
Oxacillin Ampicillin Carbenicillin |
|
|
Enzyme which confers β-lactam resistance to bacteria
|
β-lactamase
|
|
|
Two groups of β-lactams
|
Penicillins
Cephalosporins |
|
|
β-lactam mechanism of action
|
Prevents crosslinking of peptidoglycan chains causing structural weakness
|
|
|
Enzymes which cross-link peptidoglycan chains
|
Transpeptidases / Penicillin-binding proteins (PBP)
|
|
|
Timeline of Staph aureus antibiotic treatment
|
40's treated with pencillin
60's Treated with Methicillin 00's Treated with Vancomycin (emerging resistance) |
|
|
Diseases caused by Staphylococcus aureus
|
Skin/wound infections
Pneumonia Blood poisoning TSS (Toxic-Shock-Syndrom) SSSS (Staphylococcal- Scalded-Skin-Syndrom) |
|
|
Factors of MRSA infection
|
Crowding
skin-to-skin Contact Compromised skin (cuts) Contaminated surfaces low Cleanliness |
|
|
No. of MRSA infections and deaths in English hospitals in recent years
|
7000 - 8000 infections
~1000 deaths |
|
|
Infections that are a result of treatment in a hospital or a healthcare service unit.
|
Nosocomial infections
|
|
|
Clostridium difficile characteristics
|
Gram-positive rods
Spore forming Anaerobic |
|
|
Staphylococcus aureus characteristics
|
Gram-positive cocci
Not spore forming Facultative anaerobe |
|
|
C. difficile associated diseases (CDAD)
|
Pseudomembranous colitis (PMC)
Antibiotic-associated diarrhea (AAD) (15 - 25%) Perforation of the colon Toxic megacolon Sepsis Death (rarely) |
|
|
C. difficile associated disease symptoms
|
Watery diarrhea
Fever Loss of appetite Nausea Abdominal pain |
|
|
Where C. diff spores germinate
|
Small intestine
|
|
|
How does C. diff evade phagocytosis
|
A polysaccharide capsule
|
|
|
Diagnostic tests for C. diff
|
Colonoscopy
Sigmoidoscopy Toxin test Stool sample Antigen detection |
|
|
People at risk of C. diff infection
|
Elderly
staying in a hospital or nursing home taking antibiotics compromised immune systems recently had gastrointestinal surgery |
|
|
superficial, cutaneous fungal infections
|
Dermatophytes
|
|
|
Examples of dermatophytes
|
Dandruff
Onychomycoses Ringworm |
|
|
Candida spp. In the bloodstream
|
Candidaemia
|
|
|
Fungal cells in the bloodstream
|
Fungaemia
|
|
|
Type of patients susceptible to Candidaemia
|
Immunocompromised
Post surgery Very young (<1yr) Very old (>65yr) |
|
|
Fungal infection
|
Mycosis
|
|
|
Fungal equivalent of cholesterol
|
Ergosterol
|
|
|
Class of anti-fungal drugs which bind to Ergosterol
|
Polyenes
|
|
|
How non-polyene anti-fungal drugs work
|
Target enzymes responsible for ergosterol or glucan synthesis
|
|
|
Anti-fungal drugs which target glucan synthesis
|
Echinocandins
|
|
|
Malarial vector
|
Female Anopheles mosquito
|
|
|
Parasite which causes the deadliest form of malaria
|
Plasmodium falciparum
|
|
|
Parasite which causes the most widespread form of malaria
|
Plasmodium vivax
|
|
|
Number of cases of malaria worldwide
|
100 million
|
|
|
Number of deaths cased by malaria per year
|
1 million
|
|
|
Elongated form of the plasmodium parasite during transmission from mosquito to human
|
Sporozoite
|
|
|
Stage of the plasmodium life cycle in the liver
|
Exoerythrocitic stage
|
|
|
Form of plasmodium which infects RBC's
|
Merozoites
|
|
|
preventative medicine
|
Prophylaxis
|
|
|
Antimalarial drugs
|
Quinine
Cloroquine Artemisinin |
|
|
Genetic disorders which confer increased resistance to malaria
|
Sickle cell anemia
Thalassemia's |
