Exam 1 Microbiology
Vitamin C / Sepsis article
the leading cause of death in American hospitals. The treatment is aimed at sepsis, a condition in which the body's inflammatory response rages out of control in reaction to an infection, often leading to organ damage or failure. The (sepsis) treatment is a cocktail of intravenous vitamin C, vitamin B1 (thiamine) and corticosteroids. the sepsis reaction generates large amounts of a damaging molecule called reactive oxygen, which vitamin C neutralizes.
FDA hand washing article
According to the U.S. Food and Drug Administration (FDA), there isn't enough science to show that over-the-counter (OTC) antibacterial soaps are better at preventing illness than washing with plain soap and water. the manufacturers haven't proven that those ingredients are safe for daily use over a long period of time. Also, manufacturers haven't shown that these ingredients are any more effective than plain soap and water in preventing illnesses and the spread of certain infections. The FDA's final rule covers only consumer antibacterial soaps and body washes that are used with water. It does not apply to hand sanitizers or hand wipes. It also does not apply to antibacterial soaps that are used in health care settings, such as hospitals and nursing homes.
Seeing the Beautiful Intelligence of Microbes
Bacterial biofilms and slime molds are more than crude patches of goo. Detailed time-lapse microscopy reveals how they sense and explore their surroundings, communicate with their neighbors and adaptively reshape themselves. When bacteria were first observed through a microscope, suspended in liquid on slides, in their simplicity they seemed like the archetypes of primitive, solitary cells. The truth, however, is that in the wild, most bacteria are highly gregarious. Some bacteria do swim through their environment as lonely individuals but most bacterial cells — and most species of bacteria — prefer to live in compact societies called biofilms anchored to surfaces. (The individual swimmers often represent offshoots of biofilms, seeking to colonize new locations.) Within the biofilm, the bacteria divide the labor of maintaining the colony and differentiate into forms specialized for their function. In this biofilm of the common soil bacterium Bacillus subtilis, for example, some cells secrete extracellular matrix and anchor in place, while some stay motile; cells at the edges of the biofilm may divide for growth, while others in the middle release spores for surviving tough conditions and colonizing new locations.
WHO calls for urgent action to end TB
Fewer people fell ill and died from tuberculosis (TB) last year but countries are still not doing enough to end TB by 2030, warns the World Health Organization (WHO). Underreporting and under-diagnosis of TB cases remains a major challenge. Of the 10 million people who fell ill with TB in 2017, only 6.4 million were officially recorded by national reporting systems, leaving 3.6 million people undiagnosed, or detected but not reported. Ten countries accounted for 80% of this gap, with India, Indonesia and Nigeria topping the list. Less than half of the estimated one million children with TB were reported in 2017, making it a much higher gap in detection than that in adults.
World leaders commit to bold targets and urgent action to end TB
Heads of state and government attending this first-ever UN High-level meeting on TB agreed to mobilize US$ 13 billion a year by 2022 to implement TB prevention and care, and US$ 2 billion for research. They committed to take firm action against drug-resistant forms of the disease; build accountability and to prioritize human rights issues such as the stigma that still prevails around TB in many parts of the world.
Some of my Best Friends are Germs article
It turns out that we are only 10 percent human: for every human cell that is intrinsic to our body, there are about 10 resident microbes — including commensals (generally harmless freeloaders) and mutualists (favor traders) and, in only a tiny number of cases, pathogens. To the extent that we are bearers of genetic information, more than 99 percent of it is microbial. And it appears increasingly likely that this "second genome," as it is sometimes called, exerts an influence on our health as great and possibly even greater than the genes we inherit from our parents. But while your inherited genes are more or less fixed, it may be possible to reshape, even cultivate, your second genome. begin regarding the human body as "an elaborate vessel optimized for the growth and spread of our microbial inhabitants." This humbling new way of thinking about the self has large implications for human and microbial health, which turn out to be inextricably linked. Disorders in our internal ecosystem — a loss of diversity, say, or a proliferation of the "wrong" kind of microbes — may predispose us to obesity and a whole range of chronic diseases, as well as some infections. Our resident microbes also appear to play a critical role in training and modulating our immune system, helping it to accurately distinguish between friend and foe and not go nuts on, well, nuts and all sorts of other potential allergens. Some researchers believe that the alarming increase in autoimmune diseases in the West may owe to a disruption in the ancient relationship between our bodies and their "old friends" — the microbial symbionts with whom we coevolved It turns out the oligosaccharides are there to nourish not the baby but one particular gut bacterium called Bifidobacterium infantis, which is uniquely well-suited to break down and make use of the specific oligosaccharides present in mother's milk. When all goes well, the bifidobacteria proliferate and dominate, helping to keep the infant healthy by crowding out less savory microbial characters before they can become established and, perhaps most important, by nurturing the integrity of the epithelium — the lining of the intestines, which plays a critical role in protecting us from infection and inflammation. scientists can't even yet say with confidence exactly what a "healthy" microbiome should look like. But some broad, intriguing patterns are emerging. More diversity is probably better than less, because a diverse ecosystem is generally more resilient — and diversity in the Western gut is significantly lower than in other, less-industrialized populations. The gut microbiota of people in the West looks very different from that of a variety of other geographically dispersed peoples. So, for example, the gut community of rural people in West Africa more closely resembles that of Amerindians in Venezuela than it does an American's or a European's. These rural populations not only harbor a greater diversity of microbes but also a different cast of lead characters. American and European guts contain relatively high levels of bacteroides and firmicutes and low levels of the prevotella that dominate the guts of rural Africans and Amerindians. (It is not clear whether high or low levels of any of these is good or bad.) Why are the microbes different? It could be the diet, which in both rural populations features a considerable amount of whole grains (which prevotella appear to like), plant fiber and very little meat. (Many firmicutes like amino acids, so they proliferate when the diet contains lots of protein; bacteroides metabolize carbohydrates.) As for the lower biodiversity in the West, this could be a result of our profligate use of antibiotics (in health care as well as the food system), our diet of processed food (which has generally been cleansed of all bacteria, the good and the bad), environmental toxins and generally less "microbial pressure" — i.e., exposure to bacteria — in everyday life. All of this may help explain why, though these rural populations tend to have greater exposures to infectious diseases and lower life expectancies than those in the West, they also have lower rates of chronic disorders like allergies, asthma, Type 2 diabetes and cardiovascular disease. Our gut bacteria also play a role in the manufacture of substances like neurotransmitters (including serotonin); enzymes and vitamins (notably Bs and K) and other essential nutrients (including important amino acid and short-chain fatty acids); and a suite of other signaling molecules that talk to, and influence, the immune and the metabolic systems. Some of these compounds may play a role in regulating our stress levels and even temperament: when gut microbes from easygoing, adventurous mice are transplanted into the guts of anxious and timid mice, they become more adventurous. The expression "thinking with your gut" may contain a larger kernel of truth than we thought. some bacteria, like the bifidobacteria and Lactobacillus plantarum (common in fermented vegetables), seem to directly enhance its function. These and other gut bacteria also contribute to its welfare by feeding it. Unlike most tissues, which take their nourishment from the bloodstream, epithelial cells in the colon obtain much of theirs from the short-chain fatty acids that gut bacteria produce as a byproduct of their fermentation of plant fiber in the large intestine. But if the (gut's) epithelial barrier isn't properly nourished, it can become more permeable, allowing it to be breached. Bacteria, endotoxins — which are the toxic byproducts of certain bacteria — and proteins can slip into the blood stream, thereby causing the body's immune system to mount a response. This resulting low-grade inflammation, which affects the entire body, may lead over time to metabolic syndrome and a number of the chronic diseases that have been linked to it. "The big problem with the Western diet," Stephen O'Keefe said, "is that it doesn't feed the gut, only the upper G I. All the food has been processed to be readily absorbed, leaving nothing for the lower G I. But it turns out that one of the keys to health is fermentation in the large intestine." And the key to feeding the fermentation in the large intestine is giving it lots of plants with their various types of fiber, including resistant starch (found in bananas, oats, beans); soluble fiber (in onions and other root vegetables, nuts); and insoluble fiber (in whole grains, especially bran, and avocados). With our diet of swiftly absorbed sugars and fats, we're eating for one and depriving the trillion of the food they like best: complex carbohydrates and fermentable plant fibers. The byproduct of fermentation is the short-chain fatty acids that nourish the gut barrier and help prevent inflammation. And there are studies suggesting that simply adding plants to a fast-food diet will mitigate its inflammatory effect.
Romaine to Honey Smacks Cereal: Why Were There So Many Foodborne Outbreaks in 2018?
Not necessarily more outbreaks, but better ability to detect/report. One technological advance that has led to improvements in foodborne outbreak detection is the ability to sequence the whole genome of the microbe causing the illnesses. in recent years, state and local health departments have received an increase in resources, in the form of money and expertise, to collect data and investigate foodborne illness outbreaks An outbreak might be caused by more than one food, or have more than one source; and cases may be detected over a long period of time
Pandemic alert: Tuberculosis is world's No. 1 infectious killer
On Monday the World Health Organization released its 2017 Global Tuberculosis Report, and the latest picture is still one of extreme gravity, as progress to stop the spread of this disease simply isn't fast enough to make major headway: In 2016, 10.4 million people fell sick with TB, and about 1.7 million people — including 400,000 with concomitant HIV — succumbed to the deadly infection. Russia came to us a couple of years ago and said they need to do something about tuberculosis because they have a major problem with multidrug-resistant TB. worldwide there were about 600,000 new cases estimated to have emerged in 2016 that were resistant to rifampcin, the most effective first-line drug. Of these cases, 490,000 had multidrug-resistant TB, or MDR-TB, according to the WHO report. Nearly half of all cases occurred in India, China and the Russian Federation. Treatment for MDR-TB is a vicious cycle of daily injections and pills, which can come with major side effects. Courses are said to last six months, but in reality most run two years, sometimes four.
Mapping the Great Indoors
Once ecologists have more thoroughly identified indoor species, they hope to come up with strategies to scientifically manage homes, by eliminating harmful taxa and fostering species beneficial to our health. The yearlong investigation will tackle a pressing concern: One in every 20 patients acquires infections in a hospital, to the tune of an estimated 1.7 million infections and 60,000 deaths annually, according to the Centers for Disease Control and Prevention. Dr. Gilbert said, "The whole reason for doing this study is to stop people from dying."
Healthy Soil Microbes, Healthy People
Scientists in the Human Microbiome Project set as a core outcome the development of "a twenty-first century pharmacopoeia that includes members of the human microbiota and the chemical messengers they produce." In short, the drugs of the future that we ingest will be full of friendly germs and the food they like to eat. we have recklessly devastated soil microbiota essential to plant health through overuse of certain chemical fertilizers, fungicides, herbicides, pesticides, failure to add sufficient organic matter (upon which they feed), and heavy tillage. These soil microorganisms -- particularly bacteria and fungi -- cycle nutrients and water to plants, to our crops, the source of our food, and ultimately our health. Soil bacteria and fungi serve as the "stomachs" of plants. They form symbiotic relationships with plant roots and "digest" nutrients, providing nitrogen, phosphorus, and many other nutrients in a form that plant cells can assimilate. Reintroducing the right bacteria and fungi to facilitate the dark fermentation process in depleted and sterile soils is analogous to eating yogurt (or taking those targeted probiotic "drugs of the future") to restore the right microbiota deep in your digestive tract. Just as the microbes in the human body both aid digestion and maintain our immune system, soil microorganisms both digest nutrients and protect plants against pathogens and other threats. For over four hundred million years, plants have been forming a symbiotic association with fungi that colonize their roots, creating mycorrhizae (my-cor-rhi-zee), literally "fungus roots," which extend the reach of plant roots a hundred-fold. These fungal filaments not only channel nutrients and water back to the plant cells, they connect plants and actually enable them to communicate with one another and set up defense systems. With regard to stabilizing our increasingly unruly climate, soil microorganisms have been sequestering carbon for hundreds of millions of years through the mycorrizal filaments, which are coated in a sticky protein called "glomalin." Microbiologists are now working to gain a fuller understanding of its chemical nature and mapping its gene sequence. As much as 30 to 40 percent of the glomalin molecule is carbon. Glomalin may account for as much as one-third of the world's soil carbon -- and the soil contains more carbon than all plants and the atmosphere combined. modern agriculture has become one of the biggest causes of climate instability. Our current global food system, from clearing forests to growing food, to fertilizer manufacturing, to food storage and packaging, is responsible for up to one-third of all human-caused greenhouse-gas emissions. This is more than all the cars and trucks in the transportation sector, which accounts for about one-fifth of all green house gases globally. The single greatest leverage point for a sustainable and healthy future for the seven billion people on the planet is thus arguably immediately underfoot: the living soil, where we grow our food
WHO Sets Disease Priorities for 2018; Tuberculosis Once Again Not Included: Public Health Watch
Several diseases were discussed but ultimately not included on the priority list—most notably, chikungunya, emergent non-polio enteroviruses, and severe fever with thrombocytopenia syndrome (SFTS). Diseases such as dengue, yellow fever, HIV/AIDs, tuberculosis (TB), malaria, influenza, smallpox, cholera, leishmaniasis, West Nile Virus, and the plague (which has been identified recently in Madagascar) were deemed "outside of the current scope" of the WHO's R&D priority blueprint. TB's exclusion from the 2017 list caused a fair bit of controversy within the field.
Listeria pathogen is prevalent, persistent in retail delis
She said that delis' standard sanitation operating procedures can keep the bacteria at bay only if the delis are in good condition, thoroughly cleaned and have sloped floors. But cleaning and sanitation may not effectively manage Listeria in a deli with structural damage such as missing grout, loose wall coverings or a drain that is not working properly. L. monocytogenes can flourish when it finds a moist niche that is infrequently cleaned. Delis with contamination problems should "minimize the 'stuff' in the deli," Oliver said, to make it possible to clean the area thoroughly and train employees on how to maintain a sterile environment.
A Look inside the Listeria monocytogenes Biofilms Extracellular Matrix
The ability of L. monocytogenes to persist in environments is due to its capacity to form biofilms that are a sessile community of microorganisms embedded in a self-produced matrix of extracellular polymeric substances (EPS's) EPS extraction and analysis led to the identification of polysaccharides, proteins, extracellular DNA, and other molecules within the listerial ECM.
Mitigation of Listeria monocytogenes in Ready-to-Eat Meats Using Lactic Acid Bacteria
The control of L. monocytogenes in RTE meat products, especially high-risk ones such as hot dogs and deli meats, relies on the use of intensive environmental sanitation programs, thermal processing, such as cooking or in-package pasteurization, and the incorporation of antimicrobial agents as part of the ingredient formulation (e.g., nitrites, acetates, citrates, diacetates, lactates and proprionates) and sometimes as surface sprays (e.g., lauric arginate and essential oils). In foods, biocontrol is typically done by two groups of biological agents: bacteriophages, or viruses that specifically infect bacteria, and lactic acid bacteria (LAB). This heterogeneous group of bacteria may exert their antilisterial effect by means of two processes: Competitive inhibition: When LAB products such as bacteriocins and other antimicrobial peptides, as well as organic acids from carbohydrate fermentation, create an inhospitable environment for Listeria to thrive, hence reducing its numbers. Competitive exclusion: When LAB occupy space that Listeria may use for attachment or colonization, leaving the pathogen without a physical site to anchor and multiply. Based on current data, it is possible to infer that LAB have the ability to reduce L. monocytogenes either as an ingredient in product formulation or as part of a biosanitizing program.
Clues to a deadly medical mystery hide in Arizona's romaine lettuce fields
The crevices in the crispy leaves offer shelter for bacteria, keeping them safe from ultraviolet light, wind and rain that otherwise would kill them. And once the bacteria take hold in those microscopic nooks, they can't be washed or even cooked off. FDA investigators were not able to determine the cause of the outbreak. Was it the local water source/canal? A nearby cattle farm? Goose poop? After the Yuma outbreak, industry officials formed a task force to strengthen internal standards. The Arizona Leafy Greens Marketing Agreement adopted new rules it said will be enforced through audits and farm inspections. Triple the amount of setbacks from animal enclosures, such as the cattle feeding operation, to create 1,200-foot buffer zones. Conduct new environmental assessments after floods, frost or high winds. Increase the frequency and timing of cleaning and sanitizing harvest equipment. Identify all products by lot numbers to aid in traceability.
Link between antibiotics, bacterial biofilms and chronic infections found
The link between antibiotics and bacterial biofilm formation leading to chronic lung, sinus and ear infections has been found, researchers report. The study results illustrate how bacterial biofilms can actually thrive, rather than decrease, when given low doses of antibiotics. Results of this study may lead to new approach for chronic ear infections in children. During the study, non-typeable Haemophilus influenzae (NTHi) bacteria a common pathogen of humans was exposed to non-lethal doses of ampicillin, a class of antibiotics commonly used to treat respiratory, sinus and ear infections, or other beta-lactam antibiotics. The dose of the antibiotic was not enough to kill the bacteria which allowed the bacteria to react to the antibiotic by producing glycogen, a complex sugar often used by bacteria as a food source, to produce stronger biofilms when grown in the laboratory. With the introduction of antibiotic-produced glycogen, the biofilms have an almost endless food source that can be used once antibiotic exposure has ended. What may appear to be antibiotic resistance when an infection does not clear up may actually be biofilms at work.
Quartz Triclosan Article
Triclosans is rampant in countless self-care products in the US, including after-shave, moisturizers, deodorants, body sprays, face masks, dry shampoos, and hand sanitizers, and even a popular toothpaste. It—or one of its chemical cousins—is also often found in "germ-fighting" or "anti-bacterial" versions of just about any type of household product you can imagine: toys, knives, clothing, mouse pads. FDA's final rule, which targeted 19 antiseptic agents and gave companies one year to remove them from their products, only applies to hand and body soaps. Many products containing antimicrobials in the US aren't regulated by the FDA. They are considered pesticides and thus fall to the Environmental Protection Agency to regulate. the FDA rule doesn't apply to restaurants and hospitals, so the soap stocked in bathrooms outside your home could still be laced with banned antimicrobials. the FDA's ban doesn't address two other antimicrobial chemicals that are also potentially hazardous to human health—benzethonium chloride and benzalkonium chloride—which companies routinely use as a substitute for triclosan. Here's what we now know about triclosan: It's a endocrine disruptor that interferes with thyroid, testosterone and estrogen regulation and has been linked to issues like "early puberty, poor sperm quality, infertility, obesity and cancer." It has been shown to damage brain development during fetal development in rats. It almost certainly disrupts the microbiome in our guts. Because of its presence in surface, ground, and drinking water, and in wastewater plants, it's likely contributing antibiotic resistance, a grave public health concern. A CDC study found triclosan present in the urine of nearly 75% of people tested. Other studies have found it in human urine, blood and breast milk.
Why Most Americans Refrigerate Raw Shell Eggs and Europeans Often Don't
USDA requires raw shell eggs to be washed before they are sold. After being rinsed in hot water and dried, most large-volume processors then use a sanitizing rinse at the processing plant (this step is required for all USDA-graded eggs). Many processors then apply a light coating of food-grade mineral oil to the eggs to keep them from drying out. In the U.K., the majority of egg producers vaccinate hens to help prevent Salmonella and generally do not wash or clean raw eggs before sending them to market because it may damage the shell, which can function as a barrier to pathogens. Their philosophy is to retain the thin coating called the "cuticle" that naturally occurs on the outside of the egg. Refrigerating raw eggs is discouraged in the U.K. since the condensation that occurs after eggs are chilled and then warmed could potentially allow Salmonella bacteria to get inside the shell.
Hygiene Experiment Article
companies like AOBiome are interested in how we can manipulate the hidden universe of organisms (bacteria, viruses and fungi) teeming throughout our glands, hair follicles and epidermis. They see long-term medical possibilities in the idea of adding skin bacteria instead of vanquishing them with antibacterials — the potential to change how we diagnose and treat serious skin ailments. In-house lab results show that AOB activates enough acidified nitrite to diminish the dangerous methicillin-resistant Staphylococcus aureus (MRSA). A regime of concentrated AO+ caused a hundredfold decrease of Propionibacterium acnes, often blamed for acne breakouts. And the company says that diabetic mice with skin wounds heal more quickly after two weeks of treatment with a formulation of AOB. N. eutropha is an ammonia oxidizer.