BLOG 13 - DEFINITIONS

Medical mycology is the field of medicine that is concerned with diagnosing, managing, and preventing fungal diseases known as mycoses.

Amphotericin B is the “gold standard” of antifungals but is also the most toxic to humans.

All four are dimorphic (have two forms), growing as multicellular thalli below 30°C, and as spherical yeast cells at body temperature (37°C). The yeast cells express a variety of characteristics that make them invasive and better able to thrive in the body.

Histoplasma capsulatum causes histoplasmosis and is the most common fungal pathogen in humans. It is found in moist soils containing high levels of nitrogen, usually from bird and bat droppings. There are two strains: capsulatum and duboisii.

Blastomycoses are caused by Blastomyces dermatitidis. The organism grows in organically rich soil and gets into the lungs through inhalation of fungal spores in dust, resulting in pulmonary blastomycosis.

Coccidioidomycosis is caused by Coccidioides immitis. Fungi can be recovered from desert soil and materials coated with dust from endemic areas.

Paracoccidioides brasiliensis causes paracoccidioidomycosis. The organism lives in cool, damp soil from southern Mexico through South America.

BLOG 12 - REFLECTION

DIFFERENCE BETWEEN INNATE IMMUNE RESPONSE AND ADAPTIVE IMMUNE RESPONSE

1. The innate immune response is an immediate response that begins to take place as soon as a protective body barrier (e.g. the skin) has been breached by a pathogen, whereas the adaptive immune response is generated over a period of 3-4 days
2. The innate immune response recognizes broad categories of pathogens, while the adaptive immune response is VERY pathogen specific.
3. The adaptive immune response has memory, while the innate response does not.

BLOG 11 - ENCOUNTER

Blog 10 - Investigation

INVESTIGATION OF E. COLI (ESCHERICHIA COLI)

 
 
Definition

• Escherichia coli is a bacteria that normally lives in the intestines of healthy people and animals
• Most E. coli are harmless or cause relatively brief diarrhea
• But a few particularly nasty strains, such as E. coli O157:H7, can cause severe abdominal cramps, bloody diarrhea and vomiting.
• You may be exposed to E. coli from contaminated water or food; especially raw vegetables and undercooked ground beef
• Healthy adults usually recover from infection with E. coli O157:H7 within a week, but young children and older adults can develop a life-threatening form of kidney failure called hemolytic uremic syndrome (HUS).

Symptoms

Signs and symptoms of E. coli O157:H7 infections typically begin three or four days after exposure to the bacteria, though you may become ill as soon as one day afterward to more than a week later. Signs and symptoms include:

• Diarrhea, which may range from mild and watery to severe and bloody
• Abdominal cramping, pain or tenderness
• Nausea and vomiting, in some people

When to see a doctor

Contact your doctor if your diarrhea is persistent, severe or bloody.


Causes

• Among the many strains of E. coli, only a few trigger diarrhea
• One group of E. coli which includes O157:H7 produces a powerful toxin that damages the lining of the small intestine, which can cause bloody diarrhea
• You develop an E. coli infection when you ingest this strain of bacteria
• Potential sources of exposure include contaminated food or water, and person-to-person contact

Contaminated food
The most common way to acquire an E. coli infection is by eating contaminated food, such as:

• Ground beef. When cattle are slaughtered and processed, E. coli bacteria in their intestines can get on the meat. Ground beef combines meat from many different animals, increasing the risk of contamination.
• Unpasteurized milk. E. coli bacteria on a cow's udder or on milking equipment can get into raw milk.
• Fresh produce. Runoff from cattle farms can contaminate fields where fresh produce is grown. Vegetables such as spinach and lettuce are particularly vulnerable to this type of contamination.
• Restaurant meals. Cooks or servers who don't wash their hands after using the bathroom can transmit E. coli bacteria to food.

Contaminated water
Human and animal feces may pollute ground and surface water, including streams, rivers, lakes and water used to irrigate crops. Although public water systems use chlorine, ultraviolet light or ozone to kill E. coli, some outbreaks have been linked to contaminated municipal water supplies. Private wells are a greater cause for concern. Some people also have been infected after swimming in pools or lakes contaminated with feces.
Personal contact
E. coli bacteria can easily travel from person to person, especially when infected adults and children don't wash their hands properly. Family members of young children with E. coli infection are especially likely to acquire it themselves. Outbreaks have also occurred among children visiting petting zoos and in animal barns at county fairs.


Risk factors

E. coli can affect anyone who is exposed to the bacteria. But some people are more likely to develop problems than are others. Risk factors include:

• Age. Young children and older adults are at higher risk of experiencing illness caused by E. coli and more-serious complications from the infection.
• Weakened immune systems. People who have weakened immune systems — from AIDS or drugs to treat cancer or to prevent the rejection of organ transplants — are more likely to become ill from ingesting E. coli.
• Eating certain types of food. Riskier foods include undercooked hamburger; unpasteurized milk, apple juice or cider; and soft cheeses made from raw milk. 

Complications

Most healthy adults recover from E. coli illness within a week. But some people — particularly young children and older adults — may develop a life-threatening form of kidney failure called hemolytic uremic syndrome (HUS).

Preparing for your appointment

Most people don't seek medical attention for E. coli infections. But if your symptoms are particularly severe, you may want to visit your family doctor or seek immediate care.
What you can do
If you do go to the doctor, you may want to write a list of answers to the following questions:

• How often are you having diarrhea?
• Are you vomiting? If so, how often?
• Does your vomit or diarrhea contain bile, mucus or blood?
• Have you had a fever? If so, how high?

What to expect from your doctor
Your doctor may ask:

• When did your symptoms begin?
• Are you also having abdominal cramps?
• Have you recently traveled outside the country?
• Does anyone else in your household have the same symptoms?

Tests and diagnosis

To diagnose illness caused by E. coli infection, your doctor will send a sample of your stool to a laboratory to test for the presence of E. coli bacteria. The bacteria may be cultured to confirm the diagnosis and identify specific toxins, such as those produced by E. coli O157:H7.

Treatments and drugs

For illness caused by E. coli O157:H7, no current treatments can cure the infection, relieve symptoms or prevent complications. For most people, the best option is to rest and drink plenty of fluids to help with dehydration and fatigue. Avoid taking an anti-diarrheal medication — this slows your digestive system down, preventing your body from getting rid of the toxins.

Lifestyle and home remedies

Follow these tips to prevent dehydration and reduce symptoms while you recover:

• Clear liquids. Drink plenty of clear liquids, including water, clear sodas and broths, gelatin, and juices. Avoid apple and pear juices, caffeine, and alcohol.
• Add foods gradually. When you start feeling better, stick to low-fiber foods at first. Try soda crackers, toast, eggs or rice.
• Avoid certain foods. Dairy products, fatty foods, high-fiber foods or highly seasoned foods can make symptoms worse.

Prevention

No vaccine or medication can protect you from E. coli-based illness, though researchers are investigating potential vaccines. To reduce your chance of being exposed to E. coli, avoid risky foods and watch out for cross-contamination.
Risky foods

• Avoid pink hamburger. Hamburgers should be well-done. Meat, especially if grilled, is likely to brown before it's completely cooked, so use a meat thermometer to ensure that meat is heated to at least 160 F (71 C) at its thickest point. If you don't have a thermometer, cook ground meat until no pink shows in the center.
• Drink pasteurized milk, juice and cider. Any boxed or bottled juice kept at room temperature is likely to be pasteurized, even if the label doesn't say so.
• Wash raw produce thoroughly. Although washing produce won't necessarily get rid of all E. coli — especially in leafy greens, which provide many spots for the bacteria to attach themselves to — careful rinsing can remove dirt and reduce the amount of bacteria that may be clinging to the produce.

Avoid cross-contamination

• Wash utensils. Use hot soapy water on knives, countertops and cutting boards before and after they come into contact with fresh produce or raw meat.
• Keep raw foods separate. This includes using separate cutting boards for raw meat and foods such as vegetables and fruits. Never put cooked hamburgers on the same plate you used for raw patties.
• Wash your hands. Wash your hands after preparing or eating food, using the bathroom, or changing diapers. Make sure that children also wash their hands before eating, after using the bathroom and after contact with animals.

 

 Resource:

Mayo Foundation for Medical Education and Research (MFMER). All rights reserved. A single copy of these materials may be reprinted for noncommercial personal use only. "Mayo," "Mayo Clinic," "MayoClinic.com," "EmbodyHealth," "Enhance your life," and the triple-shield Mayo Clinic logo are trademarks of Mayo Foundation for Medical Education and Research.

BLOG 9 - Reflection

REFLECTIONS OF ANTIMICROBIAL DRUGS FROM CHAPTER 10

Penicillin

Penicillin

·          Bind to and deactivate the enzyme that cross links the NAM subunits of peptidoglycan

·          Natural drugs have limited action against most Gram – (G-) bacteria because they do not readily cross the outer membrane ·          Synthetic drugs have broader spectra of action

·          Allergic reactions against beta-lactams in some adults; monobactams are least allergenic

 
Vancomycin

Vancomycin

·          Directly interferes with the formation of alanine-alanine bridges between NAM subunits

·          Affective against most G+ bacteria but generally reserved for use against strains resistant to other drugs such as; Methicillin-resistant staphylococci aureus (MRSA)

·          Damage to ears and kidneys, allergic reactions

 



Streptomycin

Streptomycin

·          Inhibit protein synthesis by irreversibly binding to the 30S subunit of prokaryotic ribosomes ·          bactericidal by destroying outer membrane of G-bacteria

·          Broad (effective against G+ and G- bacteria

·          Damage to ears and kidneys, allergic reactions

 
 


Erythromycin

Erythromycin

·           Act by binding to the 50S subunit of prokaryotic ribosomes and preventing the elongation of the nascent protein

·          Effective against G+ and a few G- bacteria

·          Nausea, mild gastrointestinal pain, vomiting; erythromycin increases risk of cardiac arrest

Tetracycline

Tetracycline

·          Prevents tRNA molecules, which carry amino acids, from binding to ribosomes at the 30S subunit’s docking site

·          Most are broad (effective against many G+ and G- bacteria as well as against bacteria that lack cell walls, such as Mycoplasma

·          Nausea, diarrhea, sensitivity to light, forms complexes with calcium, which stains developing teeth and adversely affects the strength and shape of bones

BLOG 8 - ENCOUNTER

BLOG 8: ENCOUTER WITH MOLDED STRAWBERRIES

I was never really was a big fan of eating strawberries, I always stayed far away from them. I never tasted strawberries to even dislike them but it was something about them that made me not want even give it a taste trial. I fell in love with them one day when I was hungry and I ate without one ounce of hesitation and history took its place from there. But, the most stomach gnawing feeling came upon me when i went into the fridge and saw that the strawberries grew mold! Ewwwwwwww! I was so disgusted I didn't even bothered to eat the others that had no mold. I took it out of the fridge and analyzed it more carefully as i expressed a very disgusted look on my face. It had white or grayish projections pointing out and it made my skin crawl. I then threw it away and retrieve to do research as to why strawberries get mold and what exactly is it that causes the mold.

Why do strawberries get mold?

- moisture is the main cause of mold on strawberries

How do strawberries get mold?

- An excess of moisture causes botrytis fruit rot, also known as gray mold

- The gray mold affects the petals, flower stems, fruit caps and fruit of strawberry plants

- Gray mold is a result of the botrytis cinerea fungus

BLOG 7- DEFINITIONS

BLOG 7:

"MICROBIAL GENETICS DEFINITIONS"

Definitions for the structure and replication of genomes

Genetics

- is the study of inheritance and inherited traits


 

Genes

- are composed of specific sequences of nucleotides that code for polypeptides that code for polypeptides or RNA molecules

 

Genome

- is the sum of all the gentic material in a cell or virus

efinitions for the structure of Nucleic Acid

Base Pairs (BP)

- describes the two strands of DNA that are held together by hydrogen bonds between complementary bases of nucleic acids

Definitions for the structure of prokaryotic genomes

Chromosomes

- typically circular molecules of DNA associated with protein and RNA molecules in nucleotide  


 

Nucleotides

- localized area of the cytoplasm

 

Plasmids

- extrachromosomal DNA molecules found in prokaryotic cells

Histones

- proteins found in eukaryotic cell chromosomes

Nucleosomes

- beads of DNA; that clump with other proteins to form chromatin fibers

Definitions for DNA replication

Leading strand

- is synthesized toward the replication fork

 

Lagging strand

- is synthesized in a direction away from the replication replication fork, and discontinually in Okazaki fragments


 

Methylation

- a cell addds a methyl group to one or two bases that are part of specific nucleotide sequences