About 70% of the planet is covered in water with about 60% of your body being made up of water. Lakes, rivers, and reservoirs contain some of the most diverse and abundant communities of bacteria according to a 16S rRNA gene study by Tamames et al. (2010). Our own microbiota interact daily with these different communities as we drink, bathe, and excrete bacteria. One of the more pressing issues in today’s modern medicine is antibiotic resistant bacteria that are becoming increasingly hard to treat. Antibiotic resistance is caused by evolution of bacteria, which is the bacteria gaining antibiotic genes that increase its fitness. In the presences of antibiotics, bacteria that are lacking a resistance mutation die, whereas bacteria with immunity to antibiotics have a higher survival rate. These antibiotic resistant bacteria then pass on that resistance to antibiotics to the next generation, as well as potentially other bacteria through lateral gene transfer, which is the transfer of genetic material between a parent and daughter bacteria. Continue reading “Antibiotic Resistant Bacteria in the Human Water Cycle”
Hepatitis C virus (HCV) infection is a liver infection that is a worldwide major health problem. According to the World Health Organization (WHO), they estimated approximately 71 million people in the world with chronic HCV. In this blog I will be focusing more on chronic HCV and how it affects our gut microbiome. There are many different genotypes of the virus, and sadly there is still no pre-exposure prophylaxis available to this day but there is currently much research being done on HCV (CDC, 2018). Following the chronic infection, most people will develop cirrhosis or liver cancer. A large portion of the people who die from HCV die because they have already entered the terminal stages of cirrhosis or hepatocellular carcinoma. Cirrhosis is a serious disease that occurs once liver cells are damaged with scar tissue, when the organ starts to fail the patient will die unless they receive a liver transplant (CDC, 2018). Hepatocellular carcinoma is a type of cancer that is correlated with hepatitis C virus, hepatitis B virus, heavy drinking, iron storage diseases or aflatoxin (CDC, 2018). The most common sources of HCV infection are by injection drugs, using contaminated needles, and transfusions of blood that has not been tested for blood pathogens. Throughout the years there has been a significant amount of research on the role of gut microbiota in non-alcoholic fatty liver disease and liver cirrhosis, but there is not much research on chronic hepatitis C and the human microbiome. This is because most of the other research focuses on how alcohol affects the liver. Continue reading “How the gut microbiome is impacted: Patients with stage 4 hepatitis C virus”
Personality, according to the American Psychological Association, refers to “individual differences in characteristic patterns of thinking, feeling, and behaving”. In short, it’s what makes us us, what makes me different from you. It shapes how we process and understand our individual lives and all the nuances they bring, and in turn those experiences also shape our personality.
The Yanomami people are patches of isolated South American tribes who occupy mountainous regions of southern Venezuela. Recently, a Yanomami tribe of 34 subjects discovered by helicopter, was investigated by a team of researchers who accompanied medical care professionals who were providing care to the villagers. These researchers, Clemente et. al. (2015), then wrote the paper, “The microbiome of uncontacted Amerindians” to analyze this population which was uniquely untouched by Western Society. An interesting topic that this research paper addresses is antibiotic-resistant bacteria. Antibiotic-resistance are the adaptations of a bacterial species in response to antibiotics. Antibiotics are medications that have been developed in more recent times to destroy bacteria cells but not human cells. They do this by targeting specific differences between the two types of cells, for instance, penicillin inhibits the synthesis of the peptidoglycan layer of bacterial cell walls a feature not present in animal cells. Other bacteria have distinct DNA replication processes and some antibiotics are able to interrupt that function as well. This Yanomami population is intriguing because their microbiomes are likely the most accurate representation of an ancient human microbiome due to their isolation from the Western world. The presence of antibiotic-resistant bacteria in the Yanomami gut provides evidence for the claim that antibiotic-resistant bacteria have been around since before the invention of antibiotics, so stay tuned for a persuasive evidentiary argument further down. Clemente et. al.also state that the Yanomami population that is sampled is the most diverse microbiome ever recorded. It is important to understand what kind of diversity the researchers are talking about. The Yanomami show extremely high beta diversity when compared to Guahibo, Malawi, and U.S. populations but exhibit low alpha diversity amongst individuals in the village population. Beta diversity represents the differences in species composition among samples while alpha diversity is just the diversity of each sample. This means that the Yanomami microbiome sample is extremely unique but microbiomes within that sample are very similar, this is most likely due to the Yanomami leading vastly different lifestyles than Western societies and individuals in the village being in extremely close quarters with each other (eating the same food, drinking from the same water source, no waste removal, etc.).Continue reading “Which came first, antibiotics, or antibiotic-resistance? A study of Uncontacted Amerindians.”
Depression is a mood disorder that is heterogeneous in nature. Depression causes severe symptoms that affect how a person feels, thinks, and handles daily activities (NIMH, 2017). According to the World Health Organization, depression affects over 300 million people and is a major worldwide contributor to the burden of diseases. This is especially pertinent considering that depression is one of the mood disorders associated with suicide, some others being anxiety, schizophrenia and PTSD. On an annual basis suicide leads to the death of nearly 800,000 people and is the second leading cause of death within the age group of 15 to 29 year olds (WHO, 2017). The underlying causes of depression are a complex interaction of social, psychological, and biological factors. It is essential to analyze these factors to understand the contribution of each in the development and maintenance of major depressive disorders. Continue reading “Depression and Microbial Dysfunction: A Link Between Gut Microbiota and the Brain.”
A unique and diverse array of inter-specific relationships can be found within the microbiome of the human gut. Due to the constant flow of microbe-carrying nutrients through it, the gut is subject to a high risk of foreign invaders. Fortunately the immune system, as well as the digestive tract (with the help of its residential microbes), have processes to rid themselves of the pathogenic strains (Ichinohe et al, 2011). These bodily systems provide a unique example of positive interactions between co-existent, and co-dependent, systems. Although the body can protect itself from damage induced by invading species, certain medical diseases such as inflammatory bowel disease (IBD) and Crohn’s disease (CD), when combined with inflammation and intestinal distress are prone to exhibit symptoms such as “severe muscle wasting and fat loss” (Schieber et al 2015). Although the gut biome and the immune system may not always be capable of preventing these resultant health issues on their own, in conjunction they are capable of properly defending the body from muscular wasting caused by pathogenic effects.
Cow’s Milk Allergies are the most common food allergy in children, affecting 2-3% of these individuals in developed countries (Høst 2002). In most cases 45-50% of those affected by milk allergies will naturally resolve their allergies by their 1st year of age (Høst 2002). Milk allergies are associated with hives wheezing and or coughing immediately after consumption and symptoms such as cramps, itching, and diarrhea which take time to develop. A true milk allergy differs from lactose intolerance in that a milk allergy will involve actual immune system response whereas intolerance does not. The reasoning for allergy resolution is quite unclear but Bunyavanich et al. uses her study to connect allergy resolution to microbiome composition. To better understand this work,we can look at allergic responses and digestive issues as a response or the inability of the living microorganisms in the human body’s inability to process these allergens (Round & Mazmanian 2009). Continue reading “A Look at Resolving Milk Allergies Through the Gut”