Natural Food Contaminant: Aflatoxin

textgram_1503617864Aflatoxins are potential health hazard for human and animals, as it is a common natural contaminant of food and feed. Its prevalence is greatest in parts of the world where the climate is hot and humid. The Aspergillus fungi which produce the mycotoxins survive best in heat and humidity. As a result, although the prevalence of Aflatoxin is greatest in the developing world, climate change and global warming may lead to an increase in the occurrence of both the fungi and its toxic metabolites in parts of the world with temperate climates, like Europe and the United States.

Aflatoxin Toxicity

There are thousands of metabolites produced by filamentous fungi within the Aspergillus family, some of which are beneficial. However, approximately 400 of these metabolites have been deemed mycotoxins and are hazardous. There are four major types of Aflatoxin: B1, B2, G1, and G2; according to their fluorescent color under ultraviolet light (blue or green). Aspergillus parasiticus produces all four, while Asperigillus Flavus  produces strains B1 and B2. They are mutagenic, carcinogenic, and teratogenic; causing cancer and reproductive and development toxicity.Bio-Shield-Total-1

Commonly Contaminated Crops

Major sources of Aflatoxin in the food supply are peanuts, pistachios, Brazil nuts, cottonseed and maize. Aflatoxin is also a common contaminant of cereals (oats, rice, wheat, corn, and rye), dried fruit, coffee and cocoa beans, and cassava. Spices and herbs are often contaminated but to a lesser extent, and the toxin can be found in fermented beverages such as beer, wine, and fruit juices. Aflatoxin can enter the meat and dairy food supply through contaminated animal feed.

Aflatoxin B1

Of the major four, Aflatoxin B1 is of principal concern to human health. It is classified as a Group 1 carcinogen, meaning it definitely causes cancer in humans.
Specifically, Aflatoxin B1 causes Hepatic (liver) cancer. When ingested by ruminant animals like cows, Aflatoxin B1 is metabolized in the liver to Aflatoxin M1, which may be excreted into the milk. Aflatoxin M1, is a Group 2B carcinogen, in that it is possibly carcinogenic to humans. There are set limits on the amount of Aflatoxin B1 that is allowed in the foods to which they normally contaminate, since it is not possible to completely remove them. In the case of milk and other dairy products no amount of Aflatoxin B1 should be present, trace amounts of its metabolite Aflatoxin M1 however are permissible.

Aflatoxin Mechanism of Action

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The toxic mechanism of action for all aflatoxin involve oxidative stress, lipid peroxidation, mitochondrial damage, and cell death as a result of apoptosis (versus necrosis).

Toxic exposure may be an acute single exposure at high levels, or a chronic with low but  persistent levels—chronic exposure is most common. In addition to causing liver cancer, Aflatoxin may also have adverse affects on the immune system. It is also known that when Aflatoxin and infection with Hepatitis B are present at the same time, they cooperate to induce Hepatocellular carcinoma. Hepatitis B is the leading cause of Hepatocellular carcinoma, which is the fifth greatest malignancy worldwide, and is most prevalent in developing countries. As such the presence of Aflatoxin in the food supply, primarily in developing regions of the world, make it a significant pubic health concern.

Decontamination

Various treatment methods have been devised for the removal of Aflatoxin from contaminated food and feed. The amount of aflatoxin can be greatly reduced, but it does not appear that it can be completed removed. Physical methods of reduction include milling, microwave heating, and irradiation (ultra-violet or gamma). Chemical treatments involve using binders and sequestering agents or ozonation. However, ozonation is a rather expensive chemical process. Lastly, biodegradation can be used to decontaminate crops. Biodegradation is a biological method involving the use bacteria to detoxify aflatoxins. Flavobacterium aurentiacum as well as Mycobacterium are capable of this. However, lactobacillus does not metabolize aflatoxins, it only binds the toxin.

Summary

Aflatoxin are a family of toxic metabolites which contaminate crops used for food and feed, in humans and animals respectively.  Aflatoxin contamination and the fungi that produce the toxin are most common in developing nations and regions of the world where the climate is hot and humid. However, food supplies are regularly and increasing imported due to globalization. Likewise, global warming and climate change, may make it so that the environment here in the United States or parts of Europe favor the growth of aspergillus fungi, increasing the burden of their toxic metabolites in the environment, and food supply. Therefore, the public should have an awareness and an understanding of the presence of this natural toxin in the foods supply chain, especially with the increase in organic, vegetarian, and vegan dietary patterns.

 

 

 

 

 

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“On The Spot” with Lani – Ph.D. Grad Student.

Graduate school can be tough, but being a graduate student in the STEM can be exceptionally challenging. The challenges are not just academic, but social, and personal. In my experience being a graduate student is somewhat of a mystery to many people. To illustrate what its like to pursue a Ph.D in science, I’ve interviewed another Doctoral Candidate, from Auburn University, Alabama. She responded in pink font, and I felt it was so indicative of her personality, that I kept it. I enjoyed reading about her journey. Keep reading to find out how a one time aspiring model becomes a scientist.

Continue reading

Science Writer

15698247_10102718125616547_9037553185852513701_nI have joined forces with BioisLifeMedia.com, a new website designed ” to bring trustworthy, clear, and noteworthy biomedical science & scientific content to the public”. The concept is dear to me as It mirrors my own mission; to present science in a practical manner, in which to give the public the information they need to truly understand current issues in science.

Bio is Life Media was founded in fall 2016 by Scientists,  Lebaron Agostini and David Deming II, and Advertising Account Manager, Nate Valazquez. The interactive site does not use sensationalism and dramatised conclusions to bait the public. Bio is Life Media works to promote an interest in science by sharing the perspectives of scientists, graduates students, medical professionals, entrepreneurs, and tech innovators. This is accomplished by creating quality content that bridges the gap between the scientists/scientific information, the media, and the general public, so that society can make better informed decisions.

Two years ago when I started Aliquot the Science Spot, it was my vision, that a community of responsible scientists and medical professionals would network to change the face of science journalism as we know it. I am ecstatic to see that dream actualizing, and to be able to collaborate with other researchers who share the same vision and passion as I do.

I have signed on as a Contributor for Bio Is Life Media, and my first article with the site has recently been published. Read the article I wrote, entitled Monkey AIDS and Man.

 

#Phdlife: Friday In the Lab

I finally completed sample collection for all my experimental treatment groups. Very taxing undertaking, as I had four groups done in triplicate and the corresponding appropriate controls.

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It’s Friday, and I forget that means nothing to me, because I’m not on a 9 to 5 schedule. So, there went any lofty ideas I may have had about taking it easy, and having a half day. I decided to go for the three-hour colorimetric assay – decided to take the productive I want to graduate route. The only problem is that it is still Friday, and some people leave by 6pm and it was already 3pm and I still had sample preparation to complete before I could even get started. Continue reading

Heroin Chic: The Art of Imitating Life

images-7.jpegHeroin use in the United States has grown over the past decade into a national epidemic. What was once viewed as a drug of abuse for indigent war veterans in the 1970s and Black urban males in the 1980s has revealed itself to be in all geographical regions, in both genders, and in all races; but primarily amongst Caucasians. While the current heroin epidemic is far from glorified, there was a time —not so long ago, when such addiction was trendy.

In the 1990’s the opioid narcotic heroin was glamorized by pop culture where it featured heavily in “drug movies” such as, The Basketball Diaries, Trainspotting, Pulp Fiction, and Requiem for a Dream, and adopted in the Fashion and Art as what came to be known as: “Heroin Chic”.  Heroin Chic was blamed for the highest resurgence of heroin use for youths since the 1970’s. Continue reading

Online Science Journal: LabAnimal

Recently I was given the great opportunity to write for this awesome journal…

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LabAnimal  is a peer-reviewed journal that publishes editorial material relating to animal research. It is a subsidiary of the well-known Nature journal. LabAnimal is geared towards professionals, but is easy to digest; for anyone interested in information and methods involving the use of animals in research.

The journal can be accessed online. You can read the latest issue that I am in here My article is entitled A Novel Adjuvant Promises Improved Rabies Vaccines.

Subscriptions for monthly issues are available free for individuals involved in lab animal science. Others, as well as institutions are required to pay, but the price is reasonable.  You can subscribe at www.labanimal.com.

 

Natalie Cole & the Big Bad Wolves: Hepatitis C, Pulmonary Hypertension, & Renal Failure

When I hear a Nat King Cole song or a duet by Natalie Cole with her late great father, I think of summer afternoons driving down Ocean Parkway, heading to Coney Island with my Dad and sisters.

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Natalie Cole was a great singer in her own right, and recently passed away from Idiopathic Pulmonary Arterial Hypertension, which was undoubtedly a complication of kidney disease, subsequent to treatment for Hepatitis C – which she suffered from for over 2 decades of her life.

According to this article Natalie Cole  had undergone chemotherapeutic treatment for Hepatitis C that lead to her development of Kidney Failure in just a matter of months. Subsequently she was on hemodialysis until she received a kidney transplant in 2009. She contracted Hepatitis C from intravenous drug use, to which she has admitted to.

Pulmonary hypertension is associated with receiving hemodialysis and kidney transplantation. There is a 5 – 14% prevalence of Pulmonary Hypertension associated with renal transplant, and the prevalence with hemodialysis is as high as approximately 50%. Signs and symptoms of Pulmonary hypertension are often masked, and diagnosis may only be confirmed after right ventricular  heart failure develops. The condition is a progressive disorder, that increases both morbidity (sickness) and mortality (death). Irreversible heart failure ensues followed by death.

Hepatitis C

Hepatitis is the term for liver Inflammation. Hepatitis can be caused by many pathogens, but the main cause is viral hepatitis. There are 5 types of viral hepatitis of which Hepatitis C is one.

Hepatitis C was first characterized as non-A-non-B-hepatatis. Discovered in 1989, after an outbreak of chronic hepatitis in transfusion recipients in the 1970’s, the RNA virus causes an infectious disease that affects only humans and chimpanzees.

Hepatitis C is spread  directly from person-to person, primarily through intravenous drug use or unprotected sex (usually anal sex). It is spread through the blood and through circulation infects the Liver; where it enters the hepatocyte (liver cells) and replicates more of the virus. Therefore, It can also be contracted during blood transfusion, organ transplantation, and dialysis (if contamination is present). Tattooing and piercing are also a risk.

Once contracted the virus causes acute hepatitis which might spontaneously resolve on its own. In those whom fail to clear the virus on their own, chronic hepatitis ensues. The disease is often asymptomatic, and therefore many who are infected are unaware. Clinical manifestations present as jaundice, enlarged liver, and anorexia. The disease eventually may progress to Liver Cirrhosis and/or Liver Cancer, this often occurs within 10 to 20 years of having the disease.  Unlike Hepatitis B, there is no inoculation vaccine available against Hepatitis C.

images.jpegDespite of all this, Natalie Cole continued to sing, tour, and lead a productive life. She never gave in, and or that she will always be “Unforgettable…that’s what you are…and forevermore that’s how you’ll stay”. RIP Natalie Cole.

 

 

 

 

 

Easy Read: Telling JJ by John Woodrow Cox

Have you ever wondered about the lives of the many infants born with HIV? What becomes of their childhood and what obstacles do they face, socially, emotionally, and medically? This fascinating article: Telling JJ by John Woodrow Cox, takes us into the private life of one such little girl. This story captivated me and broke my heart at the same time. This is a must read, trust me you will have your perspective changed and your understanding of what it means to live with HIV altered, forever.safe_imageJJ has sat at this table many times coloring pictures with crayons at Children’s National Medical Center in Washington. JJ had long known that something else was wrong with her — that no one should touch her blood. A pile of medical records of children who have HIV sit atop a conference-room table at the hospital. – excerpt from Telling JJ

Since the introduction of antiretroviral drugs, mother-to-child transmission of HIV has fallen to below 1-2% in the United States. However, transmission still occurs due to missed opportunities for prevention, such as,  prenatal, intrapartum, and postnatal antiretroviral treatment to both mother and infant. Transmission can occur during pregnancy (particularly in the 3rd trimester), during labor and delivery, or during breastfeeding.

News Article from 1983 talks about Genetically Engineered Vaccines

Written  for the Wall Street Journal by Jerry E.  Bishop and Michael Waldholz, the article is entitled New Genetically Engineered Vaccines Aim at Blocking Infectious Disease in Millions.

I stumbled upon this article written way back in 1983. It’s amazing, to see what appears to be a current health issue dating back so far. I was only a fetus at the time!

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The article talks about the vaccines “being spurred by major advances in genetic engineering” The ability to manipulate genes and transfer them from one organism to another being called “new found”. The writer goes on to say that “the vaccines represent the first major change in vaccine technology in almost 200 years.”

Instead of using weakened pathogens like viruses and bacteria to make vaccines, the genetically engineered vaccines would use antigens (proteins present on the surface of microbes) to trick the body into recognizing the vaccines active agent as the pathogen itself. The problem with old vaccines is that although it seems simple to weaken  or kill a bacteria or virus, it’s actually quiet difficult. Hence why we don’t have a cure for every infectious disease. According to the article there are difficulties in the new engineered method; in that it’s still tricky to identify the right antigens to elicit the appropriate response from the body. At the time, scientists even hoped to create a multi-purpose vaccine that would present many antigens from many different pathogens.  However:

“But there is a roadblock instead of using just purified antigens as a vaccine, the New York NIH approach uses a whole virus that has been genetically manipulated to carry “foreign” genes from other viruses it is, in essence, a genetically-engineered organism that would be injected into humans. There already are fears-unfounded-the scientists say- about releasing genetically engineered organism into the environment. Federal regulators are likely to be extremely cautious about using such a vaccine in humans.” 

Book Review: the Disappearing Spoon…

The Disappearing Spoon– by Sam Kean …and other true tales of madness, love, and the history of the world from the periodic table of the elements.

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Back Cover

Why did Gandhi hate iodine (I, 53)? How did radium nearly ruin Marie Curie’s reputation? And why is gallium (Ga, 31) the go-to element for laboratory pranksters?*

The periodic table is a crowning scientific achievement ,but it’s also a treasure  trove of passion, adventure, betrayal, and obsession. These fascinating tales follow all the elements on the table as they play out their parts in human history, fiancé, mythology, conflict, the arts, medicine, and the lives of the (frequently) mad scientist who discovered them. The Disappearing Spoon masterfully fuses science with the classic lore of invention, investigation, discovery, and alchemy, from the big bang through the end of time.

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Sam Kean reading his book for an audience

My Review

I first read this national bestseller a few years ago. Yes, I know I said the same thing about the last book I reviewed; that just happened to be during the time I was applying for doctoral programs, and as a result spent a lot of time in Barnes and Nobles using up their free Wi-Fi. Anyhow, back from my tangent, this book was fascinating and fun to read.

What makes it fascinating is that it is pretty-much  history through the lens of the periodic table. It’s the interesting stories they never told you in science class, and had they, you might have paid more attention, or even developed a fond and respectable interest in chemistry. You will never look at the periodic table of elements the same way, if you remember every story, which you probably won’t, but that is the reason I bought the book.

I read the book over the course of about 3 days, I hid it in the book shelves for the first two days, but then I became afraid that it would be sold or taken off the shelves (as happened often), before I could finish it, so I ended up buying it. I’ve re-read a few chapters recently, so that I could give you guys a good review. I liked it, I think you will too. It’s definitely a great gift for a teenager, who say’s science is boring.