Malaria Case Study

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Malaria Case Study

• Arlín Toro
• Rafael Tosado
• Cole Benton

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Malaria Case Studies
Potential Courses
Study Aspect
Case Scenario
Resources/Activity

• Maps
• Basic concepts
• Malaria Life Cycle
• Travelers info.
• WHO, CDC, NIH

Case1 Malaria prophylaxis and control

• Gen. Biology
• Intro. Ecology
• Gen. Microbiology
• Parasitology

Tempting family vacation package but no time for
malaria prophylaxis

• Gen. Biology
• Microbiology
• Parasitology
• Bioinformatics
• Genetics
• Molec. Biology
• Evolution

• Bol Wrkbench
• Case it
• NCBI
• Plasmo DB
• CDC, WHO, NIAID

Case2 Parasite-drug resistance and diagnosis
challenges
Aunt Milagros died of cloroquine- resistant
malaria in 1982.
Students collecting mosquitoes find Anopheles in
a non- endemic area for malaria.

• Gen. Biology
• Parasitology
• Ecology
• Evolution
• Population Biology

• HIPRE
• My World GIS
• Transgenic
• mosquitoes

Case3 Ecology of the mosquito vector
Student products develop ilustrated materials
to use w/ deaf people, five min. comercials on
malaria prophylaxis, etc.
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• As he munched yet another piece of Christmas
  rice pudding Sebastián Román glanced about the
  gaily decorated room at his family. His
  brothers children were busily, excitedly
  comparing the presents they had pulled from
  underneath their beds earlier in this celebratory
  Three Kings Day. Family, food, music, and the
  smell of ginger and cinnamon smoldering on the
  table and sending small fragrant wisps throughout
  the house made everyone happy. Not everyone,
  Sebastián thought as he noticed his father
  staring out the kitchen window, a deep sadness on
  his face.
• What is it? Why arent you happy? Sebastián
  inquired, approaching his father and pulling back
  the curtain so he could look out at what his
  father saw.
• Im OK, he said. I was just recalling that
  when you were just a small niño, twenty years ago
  on this day, we lost Aunt Milagros. Its the
  ginger smell, I guess, that does it, that makes
  me remember that sad, sad day. I loved my sister
  and I miss her deeply.

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• You never talked about what happened to her,
  Sebastián said, putting his arm around his
  fathers shoulder. What did happen?
• Mr. Román pulled his son toward the table where
  they would soon enjoy the Feast of Epiphany on
  this, the last day of their Christmas. They sat
  down.
• In a word, malaria. Sergio Román told his
  son.
• Malaria. Román repeated.
• It could have been anything. It happened, it
  took her from us and that was all that mattered.
  Still, I never really understood that disease.
• Talking seemed to brighten Mr. Román. He
  enjoyed talking to this son who had flown home to
  their family from his university in the United
  States to share the holidays. Sebastián was a
  man now, a man a father could talk with.

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• We hadnt had malaria here in Puerto Rico for
  over twenty years when your Aunt Milagros died of
  it. He went on, She was using her teaching
  skills to educate children in the Amazon Chocó
  forest. Evidently she became infected on that
  trip and came home with the parasite already in
  her body.
• Sebastiáns mother Maria sat down beside her
  husband. She knew precisely what he would be
  talking about so seriously on this day, but she
  pretended ignorance.
• So, what are we discussing here?
• Aunt Milagros, Sebastián answered
• I should have known. Your father always, as I
  do, remembers your aunts passing on this day.
  Was he finally discussing it with you?

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• Yes, he told me about her missionary work in
  Colombia.
• Sergio continued. She took her antimalarial
  drug Chloroquine as a preventative, but it didnt
  help. I just dont understand.
• When she returned to Puerto Rico, she told us
  that she had had a fever the day before. The
  second day home here in Barranquitas she had it
  again. Then she had it again in two days after
  that. Your aunt insisted that the fever cycles
  were not, absolutely not, malaria because I
  took the drugs as required by the regimen exactly
  as I was supposed to. Maria continued her
  husbands story.
• I believed her. I still do. Sergio said.
• There was a brief silence, then Maria, her hands
  moving across her chest, said what she didnt
  want Sergio to have to say again. She died a few
  days later.

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Etiology and Epidemiology of Malaria
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• Malaria is a parasitic disease caused by a
  protozoan that replicates within red blood the
  cells (RBCs). The parasite is transmitted by a
  mosquito. Endemic malaria happens mainly in
  tropical climates where the mosquito is normally
  found.
• Countries at risk are those where mosquito
  transmission is possible but not happening
  currently. Seasonal outbrakes (mainly in summer
  months) have been reported in places such as
  Switzerland, England and New Jersey.

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• More than 100,000 people of all ages die of
  malaria each year according to the World Health
  Organization (WHO). Malaria is the second most
  devastating infectious disease in the world after
  AIDS.
• In 1980 malaria was endemic to 11 countries in
  the world. Currently, malaria transmission by
  mosquitoes happens in 107 countries according to
  the WHO.

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Level 1 QuestionsBiology of Malaria

1. Which are the etiologic agents of malaria?
2. Which species of the mosquitoe is responsible for
   transmitting the disease?
3. Describe the parasites life cycle.

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Online Resources on Malaria
CDC Malaria
Medline Plus NIH
Medline Plus Tutorial NIH
Malaria Triad Genetics Genomics
WHO/TDR Malaria Database
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Challenfes for the Diagnosis of Malaria
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• Red blood cells (RBCs) infected with Plasmodium
  falciparum become sticky and tend to adhere to
  the inner wall of blood vessels. Sequestred RBCs
  may not be evident in a smear of peripheral blood
  at the early onset of infection when the ammount
  of infected RBCs is low (low parasitemia).

Animated movie sequetred Rbcs infected With P.
Falciparum (www.whei.edu.au)
Click here view videos Penetrate and Burst
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• Microscopic identification of malaria in
  peripheral blood requires an experienced
  microscopist, especially at low parasitemias.
  Both thick and thin blood smears should be
  performed in microscope slides to assess
  parasitemia.

Thin smear preparation video demonstration (vet.u
penn.edu)
Side of fingertip
Click here
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Thick and Thin Blood Smears
deep view of blood
Thick blood smear
Thin blood Smear
Sinle-layer of RBCs
adapted from www.cdc.gov
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Level 2 QuestionsMalaria Diagnosis

1. Establish a relationship between the plasmodium
   life cycle and the periodicity of the fever
   episodes.
2. When would be the best time to take a sample of
   peripheral blood for a smear?
3. Do antibody-screening tests detect DNA mutations
   in in Drug-resistant strains?
4. Design a PCR-based method for the identification
   of chloroquine resistant strains of P. falciparum?

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Online Diagnostic Resource

• DPDx - CDC - Division of Parasitic Diseases
• Complete Information on diagnostic methods for
  parasitic disease

Click here And search on Malaria and
Diagnostic methods
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Malaria Evolutioln and Bioinformatics
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• With the use of the insecticide
  dichlorodyphenyl-trichloroethane (DDT) and the
  drug chloroquine, malaria was eradicated from
  most urban areas around the world in the 1950s.
  Since the late 1970s the parasite began to
  develop resistance to chloroquine and the
  mosquito developed resistance to DTT.

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• There are different mechanisms of resistance
  related to different anti-malarial drugs.
• Resistance to chloroquine and mefloquine in P.
  falciparum arose simultaneously in the early
  1980s in South America and South east Asia.
• Mutations in the pfmdr gene have been associated
  wit multi-drug resistance. This gene encodes a
  trans membran-efflux pump.

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Malaria basics
CDC Malaria
MedlinePlus NIH
MedlinePlus Tutorial NIH
Malaria Triad Genetics Genomics
WHO/TDR Malaria Database
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Level 3 Questions

• Using bioinformatics tools, find the protein
  sequence with higher similarity to the Plasmodium
  falciparum mdr.
• Based on the sequence alignments of the mdr
  protein find potential differences in the
  structure responsible for drug resistance.
• P. falciparum is more virulent than the other
  species that cause malaria in humans. Can this be
  explained in evolutionary terms? Compare the mdr
  protein sequence from different Plasmodium
  species.

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Retrieving protein sequencesfrom NCBI Protein
Data Bank
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Retrieving protein sequences

• Click on the NCBI link on the right side.
• Search for Plasmodium falciparum mdr
• Select Protein sequence database
• Establish limits (ref seq) Change the display
  mode to FASTA

NCBI
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(No Transcript)
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Click on Protein sequence database
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• You will obtain an incredible number of matches.
• Lets type Plasmodium falciparum.

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Notice the number of hits is lower. Lets try
adding mdr (multidrug resistance) and click go.
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• Now you got only 19 hits.
• Click on limits to look for curated data

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• Select from this pull down menu RefSeq.
• Click go

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• This is your accession number, write it down.
  You will need this number if you need to retrieve
  this number.
• Click on the accession number

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• The first part of the record consist of general
  protein information.

• This number is the accession number of GenBank.
  If you click on it you will be directed to the
  gene sequence.

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• When you scroll down the record you will find
  information related to the protein function.

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• The last part of your record is the protein
  sequence.
• Now, lets compare this protein with other known
  proteins.

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• Click on Blink

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• Select from this pull out menu FASTA.

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• Click on best hits

• To view the structure of

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• Select sort by taxonomy proximity
• Observe that your list order is different

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• Click select GI list

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• Select the sequences the first two sequences.

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• All the sequences that you selected will appear
  in this format

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• Select from this pull down menu send to file
• Save it

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In this part you are going to work with Biology
Workbench
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Biology Workbench

• If you have no experience with Biology workbench
  click on the Tutorial, complete the tutorial
  before you start with this unit.
• If you just want a quick review you may proceed
  to the next part.

Biology Workbench Tutorial
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• Biology Workbench its free but you have to open
  an account.
• Select the Biology Workbench link.

Biology Workbench
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• Register to create an account in Biology
  Workbench.

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• Enter the Biology Workbench.

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• Scroll down to the button of this page.

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• Select the session tools.

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• Select start new session from the pull out menu.

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• Write down the name of the session.
• Click on the Start Session button

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• Select Protein Tools

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• From the pull down menu select add new protein
  sequence.
• Click on run button.

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• Browse your sequences
• Click to upload the file

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• Click on save

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• Click on save

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• Click on both sequences

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• On the pull down menu select CLUSTALW
• Click on Run

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• Accept all the parameters by clicking on submit
  button

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• Scroll until you see the sequence.
• Compare your sequences.
• Check on the key colored legend.
• Compare in terms of identity

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• Click on import alignments

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• First, select your alignment
• Second, select on the pull down menu TEXTSHADE
• Third, Click on Run

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• Click on submit button

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• Your results will be in this format which is
  easier to analyze.