Our Hamburgers are Contaminated!

Previous estimates by the United States Department of Agriculture’s (USDA) Food Safety and Inspection Service (FSIS) calculated that about 5 percent of the hamburger processed in the U.S. was contaminated with Escherichia coli O157:H7.
This particular bacteria causes about 62,000 cases of food poisoning in the United States each year. Infection with this bacterium is especially dangerous to the elderly, the young, and the immunocompromised. People in these categories can experience bloody diarrhea and kidney failure. A recent report by the FSIS using a much more sensitive test indicated that almost 90 percent of the hamburger lots tested were contaminated with Escherichia coli O157:H7. This is not good news. However, you must take some of this alarming news with some amount of cautious examination. Some of those lots of hamburger only contained 100 Escherichia coli O157:H7. Those lots consist of 3000 pounds of hamburger. If you were to eat a quarter pound burger and if the Escherichia coli O157:H7 were evenly distributed you would have to eat 120 uncooked quarter pound hamburgers to get one organism. The dose of Escherichia coli O157:H7 needed to cause illness is about 10 organisms. This means that you would have to eat 1200 uncooked quarter pound hamburgers to get sick.

I don’t want you to think that I am downplaying the importance of these findings. Not all hamburger is kept at the proper temperature to prevent growth of the bacteria. One hundred organisms could quickly become 1 million organisms. Nor are bacteria evenly distributed in the meat. Some poor unfortunate person may get the only undercooked hamburger from the lot with 10 Escherichia coli O157:H7 in it and get really ill. Many of the lots of the hamburger FSIS tested contained much higher numbers of Escherichia coli O157:H7 in the meat. The bad thing about these bacteria is that you can NOT tell if the meat is contaminated. It will look fine and smell fine. However, if you do not cook it properly and are at the right age for serious complications you could become very ill.

The take home message of this story is that most hamburger packages you get from the store are contaminated with disease causing bacteria. Many people love to eat hamburger. You should not stop eating hamburger but instead you should prepare it wisely and cook it until it is well done.

You don’t have to be an unknowing victim of contaminated hamburger. Most food poisonings do NOT occur in restaurants. It is just that those outbreaks of food poisoning are more likely to be reported to the public. Uncle Bill’s Saturday night hamburger feast with four of his friends

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Alcohol with Less Severe Hangovers Created: New Scientific Discovery Reduces the After-Effects of Drinking

Most people at some point in their lives can recall a time when they have had ‘one too many’ and suffered the next day from the effects of alcohol. A team of scientists in Korea may now have found a solution to stop those ‘morning after’ feelings.

Alcohol with a Higher Oxygen Content Produces Fewer after Effects

A team of scientists from Chungnam National University in Korea carried out experiments where participants were given alcoholic drinks with varying oxygen content levels. Results showed that those participants who had greater levels of oxygen within their drinks sobered up significantly quicker than those with lower levels in their beverages.

According to The Telegraph newspaper, when a person drinks alcohol, Oxygen in the body turns the alcohol into water and carbon dioxide. The study in Korea found that when Oxygen concentrations in alcoholic drinks are increased, it would appear that the process of the human body dealing with alcohol and breaking it down is speeded up.

The Common Hangover

The effects that alcohol will have on a person varies between individuals. Some people have a higher tolerance to alcohol than others and factors such as a person’s height, build and age can also lead to how well the body deals with the consumption of alcohol.

According to http://www.howstuffworks.com, other physical factors such as;

  • How tired a person is before drinking alcohol,
  • How much they have had to eat before drinking alcohol,
  • how well hydrated they are beforehand, and,
  • Level of physical activity a person does whilst drinking alcohol ,

Can all affect how a person responds when consuming alcohol; this is one of the reasons why individuals find their tolerance to alcohol varies depending on their situation when consuming an alcoholic drink. Those people who have been dancing at the same time as drinking may find that they suffer more severe hangover the next day due to the added effects of dehydration that the dancing caused.

Scientists don’t fully understand all the causes of hangovers but the primary symptoms including headache’s, nausea and vomiting result from a combination of various chemical imbalances being caused in the body by alcohol being absorbed (www.howstuffworks.com).

Hangovers won’t be a Thing of the Past

The new alcohol developed by the Korean University won’t mean that those consuming it will feel no effects at all. The scientists point out that their work won’t lead to hangover free alcohol but could lead to alcohol that has the same level of alcoholic content but owing to its higher levels of oxygen, creates less severe hangovers.

The full results of the experiment can be read in the Alcoholism: Clinical and Experimental Research.

Develop Kids’ Creativity and Teach Biology: Potato Prints and Sea Shells, Ways to Create and Learn

One way to develop children’s artistic talent with lively biology lessons is to teach them how to make potato prints, dried flower pictures and sea shell gifts.

Creating works of art using natural materials like flowers, leaves and sea shells is an art lesson and a biology lesson wrapped in one. Depending on the children’s age and manual skills, one of these methods producing lovely pieces of art work will be suitable for them.

Potato Prints

Making potato prints is the easiest method and can be managed by children as young as five with the suitable help and supervision of an adult, particularly as the use of a sharp knife is involved. All that’s needed are a few fresh, good sized potatoes, a glass of water, a sharp knife, drawing paper and water colors or any other paint which dissolves in water.

First decide what you are going to make. Potato prints can be entire pictures which can be framed and hung for the proud young artist to display. Smaller formats can be turned into greeting cards and bigger sheets can even be used as personalized wrapping paper.

Next, decide on the design according to the object you wish to produce. Then cut the potato in half and again in even-sided wedges, which are to be used as print stamps. Formats can be square, round or half-moon shaped. Moisten the paint sufficiently and dip the potato stamp into the color, then print directly onto the paper. The result is a lovely, mosaic-like pattern.

Admittedly, there’s not much of a biology lesson here, but the kids’ creativity will be stimulated and they learn that natural materials can be put to different uses.

Gifts Decorated With Sea Shells

When by the ocean, take the children for a walk along the beach. They can learn about maritime life by collecting shells. Don’t let them gather broken, too dirty or too tiny shells if you wish to teach them how to decorate gifts by using sea shells. With a bit of help, this artistic activity is also suitable for younger children.

Clean the shells with the help of a steel brush and let them dry thoroughly. Select an item with a smooth surface, like a plain wooden box or an unpainted picture frame. Make sure the surface you wish to apply the shells to is very clean and dry. Turn the shells upside down and erase any irregularities of the rim with a metal or sandpaper file. Remove dust. Apply a thin layer of strong glue and press down firmly.

The shells can be used in their natural state or they can be covered with clear varnish or sprayed with gold or silver spray.

Dried Flower Pictures

Making works of art from dried flowers is a much longer process as the kids are supposed to produce the raw material themselves. Walks in the countryside or a visit to your own flower garden provide children with botanic lessons. For the ultimate purpose of making dried flower pictures it’s best to collect flowers and leaves which preserve well, such as maple leaves, oak leaves, poppy seed flowers, simple roses and pansies.

The drying process involves spreading out the collected flowers carefully so as not to damage the petals, placing them between two sheets of blotting paper and piling a few heavy books on top. Once the flowers and leaves are dry and pressed, they must be carefully removed with the help of pincers, arranged in the desired pattern and perhaps be cut to size and shape with sharp nail scissors.

Glue is applied to the surface, cardboard or silk being the most suitable, and pressed down firmly. Again, the finished art work is best preserved framed and under glass or else laminated.

Kids will be very proud to have created pieces of art, letting their fantasy and imagination guide them and, at the same time and with no effort, will have learned about botany and sea life.

Uncomplicated Gonorrhea: Cervicitis and Urethritis

Gonorrhea is a sexually transmitted infection caused by the bacterium Neisseria gonorrhoeae.

Gonorrhea is transmitted through direct close contact between individuals, usually sexual. And infection can be passed from mother to infant during passage through the birth canal. However, because N. gonorrhoeae does not survive long outside the human host, and is susceptible to temperature extremes and drying, transmission does not occur through skin to skin contact, or through contact with contaminated objects. Thus, N. gonorrhoeae cannot be contracted through contact with a contaminated toilet seat or other surface.

Gonorrhea is the second most frequently reported communicable infection in North America, second only to chlamydia.

Most cases of gonorrhea are uncomplicated genital tract infections: cervicitis in women, and urethritis in men. Infection of the lower genital tract occurs through direct inoculation of columnar epithelial cells of mucous membranes in the cervix and the urethra. Infection of the vagina does not usually occur, except in prepubescent females, where infection may involve vaginal epithelial cells and the vulva (vulvovaginitis). Changes that occur in the vaginal mucosa at puberty protect vaginal epithelial cells from invasion. Neisseria gonorrhoeae and Chlamydia trachomatis prefer columnar epithelial cells in the cervix.

  1. gonorrhoeae may also infect columnar epithelial of other mucosal surfaces: conjunctiva, throat (oropharynx) and rectal mucosa.

Most infections occur in the under age-24 group, especially those with multiple sexual partners who engage in unprotected sexual intercourse. In 2016, 340,000 cases of gonorrhea were reported to the Centers for Disease Control and Prevention (CDC). However, it is estimated that only about half of all infections are reported suggesting that approximately 700,000 cases of gonorrhea occur each year in the U.S. alone.

Gonococcal infection (gonorrhea) can be asymptomatic, especially in women. Most women who are infected do not have noticeable symptoms. Symptoms generally present 5-7 days following exposure, but may present as early as 2 days or as late as 30 days following exposure.

Symptoms of gonorrhea in men with acute urethritis include:

  • white, yellow or green discharge (scant or copious; clear or purulent),
  • frequency of urination,
  • burning during urination.

Symptoms of gonorrhea in women with acute cervicitis/urethritis include:

  • vaginal discharge,
  • pain during urination,
  • inflammation of the cervix ,
  • irritation of the cervical os (opening),
  • vaginal bleeding between periods.

Screening of women at high risk for sexually transmitted infection (STI/STD) is an essential component of the control of gonorrhea. Because gonorrhea is often asymptomatic in women, all sexually active women at increased risk should be screened for gonorrhea.

Risk factors include:

  • previous sexually transmitted infection(s),
  • new sexual partner(s),
  • multiple sexual partners,
  • inconsistent condom use,
  • drug use,
  • commercial sex trade work.

Treatment for uncomplicated gonorrhea includes:

  • Ceftriaxone (125 mg single dose intramuscular injection)
  • Cefixime (400 mg oral single dose)
  • Ciprofloxacin (500 mg oral single dose)
  • Ofloxacin (400 mg oral single dose)
  • Levofloxacin (250 mg oral single dose)

Plus treatment for chlamydia, as appropriate.

Neisseria gonorrhea may also be involved in a number of other types of infections – conjunctivitis, oropharyngitis, rectal gonorrheae and other more complicated gonococcal infections.

Anthrax in Cattle: The Risk to Humans

There are 3 main types of anthrax – cutaneous, gastrointestinal and respiratory. All three types of infection can occur in animals and humans. Spores are an important factor in transmitting infection, and animals usually become infected through grazing in areas where large numbers of spores are present in the surface of the soil (link to anthrax and cattle). Therefore natural infection in humans is not likely to occur unless they are in contact with infected animals or animal products.

Infection in animals is usually gastrointestinal, and the most likely route of infection in grazing animals is through ingestion of spores during dry periods following flooding. Spores are brought to the surface during periods of heavy rainfall and remain there and become concentrated during dry spells. Ingestion alone does not necessarily result in infection – the spores require a lesion of some sort to gain entry into the tissues. Gastrointetinal lesions may occur when grazing on dry, spiky, gritty grass that grows close to the soil – infection occurs where spores have also been deposited on the soil.

Grazing animals may also become infected through inhalation of spore-laden dust (pulmonary anthrax), although infection by this route is much less common than through ingestion. Animals that feed on the carcasses of dead animals can also become infected during outbreaks in grazing animals.

Humans become infected through contact with infected animals or animal products such as carcasses, hides, wool, hair and bone meal. Therefore, in areas where infection in livestock is uncommon, human infection is also rare.

The World Health Organization (WHO) reports higher incidence of infection in certain areas of Canada such as the MacKenzie Bison Range, North West Territory and Wood Buffalo National Park in northern Alberta, with sporadic outbreaks occurring in southern Alberta and Saskatchewan. In the U.S., sporadic cases occur in South Dakota, Nebraska and Oklahoma, with more persistent outbreaks in western Texas. In other areas of the world outbreaks occur more consistently – Central and South America, Mexico, South Africa, Middle East, Soviet Union, southern India, and south-east Asian countries (Vietnam, Cambodia, western China, Thailand).

The most common form of natural human infection is cutaneous anthrax, accounting for at least 95% of cases world-wide. Cutaneous anthrax is readily treated with penicillin and a number of other antibiotics. Without treatment, 10-20% of cutaneous infections may be life-threatening. Contact with the vegetative form of the bacteria in the fluids and tissues of sick or dying animals, or with spores in dead carcasses, meats, hides, hair, wool or bone does not guarantee infection. Infection requires a skin lesion (cut, scrape, etc.) in order to gain entry to the tissues. In 2-3 days (may occur as early as 9 hours or as long after as 7 days) a pimple-like red elevated area appears, followed 1-2 days later by a ring of blister-like, watery fluid-filled vesicles with swelling in the surrounding area. By 5-7 days, an ulcer forms (eschar) (see photo). By approximately 10 days, the eschar begins to heal and may take up to 6 weeks to resolve. Treatment at this stage does not speed healing. Without treatment a small number of cases may develop systemic infection.

Gastrointestinal and pulmonary anthrax have much higher mortality rates than cutaneous anthrax, often because they are more likely to go unrecognized and untreated. Treatment in the early stages of either infection is very effective; however, the disease progresses rapidly, and in the latter stages of infection treatment is often ineffective.

Gastrointestinal infection may occur following ingestion of raw or improperly cooked meat from sick or dead animals and symptoms are similar to other food-borne illnesses –

nausea, vomiting, fever, abdominal pain. Cases may be mild or severe – in severe cases the mortality rate is approximately 50% even with treatment.

Pulmonary anthrax is even more likely to be misdiagnosed as the initial stage of infection involves flu-like symptoms – mild fever, fatigue and malaise lasting one to several days. Without treatment at this stage, infection progresses rapidly to difficulty breathing, disorientation, toxemia and death. Naturally acquired pulmonary anthrax in humans is extremely rare.

Anthrax and Cattle: Terror on the Prairies.

Like most people, when I think of anthrax, I think of white powder, mail and terrorism plots. If I was the extremely paranoid type, the recent news reports of cattle dying of anthrax infection on farms in Saskatchewan and Manitoba might have me wondering whether our food-chain is now being targeted by terrorists.

The latest threat to Canada’s beef industry, following the mad-cow hysteria of the past few years, is anthrax. the Canadian Food Inspection Agency (CFIA) has reported 644 dead animals on 136 farms in Manitoba and Saskatchewan, most of these cattle. Why? Did terrorists tire of licking envelopes? Are they frustrated with the speed at which snail-mail is delivered? No. This recent outbreak of infection in cattle is naturally occurring, unrelated to any sort of conspiracy.

Anthrax is a zoonotic infection, primarily infecting grazing animals (herbivores) who ingest spores of the bacteria, Bacillus anthracis, found in soil. Bacillus anthracis in its spore form is extremely resistant to harsh environmental conditions such as drying, heat, cold and chemical exposure. This is the reason that anthrax spores have been popular throughout history as an agent of biowarfare and bioterror.

Not all bacteria have the ability to form spores, but for those that do, when environmental conditions become uninhabitable, the bacteria enters into a dormant or nonactive state. Once conditions improve, such as when the spore is inhaled into a nice warm moist nutritious body, animal or human, the spore changes back to its vegetative or active state and begins to grow and multiply. As Bacillus anthracis multiplies, it produces toxins that cause damage and are potentially life-threatening. Infected cattle die quickly once infected so that sick animals are not often seen.

The current outbreak is the largest recorded outbreak of zoonotic anthrax occurring over the largest area in Canada. The last largest outbreak reported by the CFIA was in 2000, involving 28 cattle – 24 in Manitoba, 3 in Ontario and 1 in Saskatchewan. There were also 10 deaths in other animals – 6 in bison (5 in Alberta and 1 in the North West Territories) and 4 in black bears, moose and wolves in Alberta. However, deaths are sporadically seen most years across the Prairie provinces. Why are we seeing so many deaths in livestock this year? The abundant rain and flooding in Saskatchewan and Manitoba this spring and early summer have been extremely favorable for bringing anthrax spores to the surface of fields and meadows where animals graze. Spores reportedly can live in the soil for 50 years or more. Once ingested by animals grazing in spore-rich areas, the bacteria causes a severe gastrointestinal infection, which very often leads to death.

What is the threat to humans? Check in next week to find out whether there is reason for concern.

Neuroscience and the Neuronal Correlates of Consciousness

Neuroscience and the Brain

Even the most enthusiastic neuroscientist will concede that the human brain is not much to look at: a 1.5kg cauliflower of grey, spongy matter. But despite their modest outward appearance, our brains are the most complex objects known to man, and still represent the greatest problem in biology: how the timed firing of electrical signals from neurons, along with glial cells and neurotransmitters, can give rise to something as remarkably abstract as our own consciousness.

With recent advances in the field of neuroscience, the way we think about the way we think is changing, and the quest for the physical basis of consciousness promises to be a voyage of discovery as fascinating as the quest for the structure of DNA in the early 1950s. But what exactly are the problems facing neuroscientists, and how are these being solved today?

Defining Consciousness and Awareness

Perhaps the first issue is in defining consciousness itself. As human beings, we experience the world. When light of a certain wavelength hits the cone photoreceptors of our retina, we experience the sensation of seeing “red”, for instance, and we have feelings that correspond to this experience.

We are also probably not the only animals who experience the world in this way. Experimenting (humanely) with chimpanzees and dolphins has demonstrated that they are capable of complex, abstract tasks such as recognising themselves in mirrors (Gallup, 1970) and planning future actions (BBC), activities which should be impossible without some form of consciousness, or inner mental life.

Even the humble fruitfly has demonstrated that it is capable of complex behaviours involving choice (Heisenberg and Wolf, 1984). As such, Descarte’s idea of there being a “threshold of consciousness” over which only humanity has stepped has begun to sound as outdated as the concept of a geocentric universe.

Are Computers Conscious?

However, a neat sliding scale of consciousness also has its faults. Everyone has experienced what happens when a computer finds a fault in its hardware: you will likely receive a cryptic error message, or simply the “blue screen of death” as the damaged system struggles to function. But the idea that computers sense this line of code as analogous to pain, or that they experience the world on any level at all, can be discarded fairly quickly.

That is not to say that this suggestion does not have its proponents. Some scientists, like David Chalmers of the University of Arizona, postulate that all systems capable of processing information, even digital systems, are conscious in some sense, if only on a rudimentary level. Chalmers does concede, however, that it would probably not feel like much “to be a thermostat” (Koch & Krick).

Were this theory correct, it would suggest that our spinal columns, for instance, along with many parts of our brain and even the 100 million or so neurons found in the intestinal wall, could themselves be conscious. After all, they, too, process enormous amounts of information every second. If they are, of course, they are certainly not telling us about it!

Studying the Brain

One problem for scientists is that in-depth study of the brain is necessarily an invasive and life-threatening procedure. Much has been learnt from studies involving electrodes measuring the brain’s electrical field from outside the skull, but this is as problematic as trying to learn about the structure of the ocean by studying its waves.

As such, a vast majority of recent developments in the science of our own minds comes from what happens when they go wrong. Patients suffering massive epileptic seizures must undergo complicated surgery to have electrodes placed inside their brain in order to locate the troublesome tissue causing their seizures. This gives scientists a unique opportunity to study the way the brain works, and in particular how its workings give rise to consciousness.

The Clinton Neuron

One remarkable discovery has involved a specific neuron found in a seizure patient that fires whenever the subject sees a picture of former US president Bill Clinton. The patient was shown photographs of other white-haired men, other former presidents and hundreds of random control pictures, none of which elicited a response. Every time Mr. Clinton entered the subject’s field of view, the electrical readings from this single neuron spiked.

The implications of this are enormous, since it places the firing of neurons right at the start of the chain of mechanisms that create consciousness. When this neuron and the possibly hundreds of other “backup” duplicates fire, they somehow start a series of events that results in the patient recognising a face. But the question remains: how does this binary system of neurons either firing or remaining dormant create the almost infinite intricacies of our minds?

The Biology of Belief by Bruce Lipton, Ph.D.

Lipton introduces in his book The Biology of Belief what he calls the new biology against the dogma of contemporary biology: DNA controls biological life. Ever since Darwin suggested in his 1859 book, The Origin of Species that “hereditary factors” passed from parent to child was the driving force for evolution, biologists were obsessed with the search for the hereditary mechanism that controlled life.

When the DNA structure and function were unveiled by James Watson and Francis Crick, the world was being taken by the rosy prospects of discovering the secrets of life. The power of DNA has grown from determining our physical characteristics, to controlling our emotions and behavior. The survival of the fittest individual is reflected in the survival of the fittest genes.

The New Biology

Against this traditional reductionist’s view of a competitive life, Lipton presents scientific evidences, including underrated old findings and exciting recent discoveries, that life is about co-operative harmony not only with other life forms, but also with the physical environment.

By expounding why and how “smart” cells, as Lipton calls them, can teach us about human mind and body, Lipton replaces the biological myths with the following conclusions:

  • Genes do not control biology in a fatalistic sense.
  • Cell membrane, instead of the DNA-containing nucleus, is the true brain of a cell.
  • The environment plays a decisive role in the behavior of cells despite the genetic codes.

How Thoughts Control Life

By explaining why quantum physics is relevant to biology, Lipton points out that the body, like the universe, is one indivisible whole with interchangeable energy and matter. Thoughts, the mind’s energy, directly influence the physical brain, long recognized as an electrical organ. The brain controls body’s physiology by activating or inhibiting proteins which in turn change the micro-environment of the cells and thus control cell functions.

Such biological consequences of thoughts or beliefs lead Lipton to call his book The Biology of Belief. The placebo effect is a prime example Lipton uses to explain the effects of mind over body. However, Lipton points out that reality is complicated by the operation of conscious and unconscious thoughts. The mere thinking of positive conscious thoughts against the more powerful unconscious programming does not change anything.

Lipton continues to illustrate the biological basis of negative thoughts, mostly related to the physiology of the flight and fight response triggered by fear. Such protective mechanism inhibits growth to conserve energy and resources for survival. The growth-inhibiting mode has profound effects on human development as far back as the time of conception. Lipton devotes a whole chapter called “Conscious Parenting: Parents as Genetic Engineers” about the importance of creating a healthy and happy environment – biologically, emotionally and physically – for the unborn children and infants.

What Lipton does not elaborate much is how an adult can undo the self-sabotaging unconscious programming to create a fulfilled life although he does mention in the Addendum that PSYCHE-K has helped him undo his self-limiting beliefs. The Biology of Belief is more a scientific exploration about how thoughts control life, rather than a self-help book with practicable steps to change one’s life.

How Do Bacteria Make People Sick?: Bacterial Pathnogenicity, Virulence Factors and Infectious Disease

In order to cause disease, potentially harmful bacteria must first enter the body, usually through breaks in the skin, penetrating the mucous membrane or colonizing the gastrointestinal (GI) tract. This is considered infection, when bacteria breech the first line defenses of the body.

Bacterial disease starts with infection, but infection does not always result in disease. Many bacteria are beneficial. And even when pathogens infect the body, the immune system may be able to eliminate the infection before symptoms of disease occur.

Bacterial Pathogenicity and Virulence

To cause disease, bacteria must be present in sufficient numbers. But what is it about bacteria that make an infected person ill? Disease is not merely caused by the presence of microbes.

Pathogenicity (path-o-jen-ISS-ity) refers to a microbe’s ability to cause disease, and some microbes are more pathogenic—better able to cause disease—than others. The degree of a microbe’s pathogenicity is considered its “virulence.” For example, highly virulent bacteria frequently cause disease, whereas less virulent bacteria may only cause disease when present in large numbers or within hosts that have weakened immune systems.

Many pathogenic, or disease-causing bacteria have special weaponry, traits that enable them to infect and damage host tissue. These disease-causing traits are called “virulence factors”. The following sections describe different types of virulence factors.

Adhesion Factors, Glycocalyces and Biofilms

Once bacteria get into the body, they must be able to stick to the host’s cells in order to increase in number. Bacteria that are able to stick to host cells have special structures or chemicals, collectively called adhesion factors. These adhesins are found on bacterial cell extensions, such as fimbriae and flagella, and also on glycocalyces, a sticky layer surrounding some bacterial cells that enable bacteria to stick to surfaces and to each other in biofilms. For example, the inside of the mouth and teeth are covered with a sticky bacterial biofilm, particularly in the morning, before brushing, because bacteria have been multiplying in the mouth throughout the night.

Bacterial Extracellular Enzymes

Some pathogenic bacteria are able to produce and secrete enzymes that compromise cell structure of the host and enable the bacteria to work their way further into the body.

Bacterial Toxins

Bacteria may also produce toxins that cause damage to host cells either directly, by destroying tissue, or indirectly, by triggering an intense or prolonged host immune response. Bacterial toxins fall into two general categories based on their position relative to the cell that produces them; exotoxins, which are secreted by bacteria, and endotoxins, such as lipid-A, which are part of the Gram-negative bacterial cell.

Evading Host Immune System

The human immune system has special white blood cells called phagocytes, which search out, engulf and digest invading pathogens. The sooner a pathogen can be eliminated from the body, the less damage it will have the opportunity to cause. However, bacteria have developed means of evading phagocytes.

The bacterial capsule, a type of glycocalyx, can help a bacterium hide from the immune system. This coating is often made of chemicals that are found in the human body, and that don’t trigger an immune response.

Other bacteria produce chemicals that prevent them from being digested once engulfed by a phagocytic white blood cell, allowing the bacteria to live and reproduce inside the host cells designed to eliminate them. Other antiphagocytic chemicals can prevent bacteria from being engulfed by white blood cell, or can even destroy white blood cells.

How We Hear – Travel Along a Sound Wave from Ear to Brain

Hearing happens in an instant – quick transformations to energy until the movement of molecules is meaningful to a listener. It’s not magic, but the small size and complexity of shapes, movements and structures involved in energy transformation makes the process seem magical. To be able to hear beautiful music or birdsong in spring or mother’s voice is an awesome act of nature.

To put it very simply, sound is a type of energy and to get it from outside the head to the place in the brain where it can be “heard,” sound energy has to be sent from the microphone to the amplifier, along wiring, and on to the translating device.

Outer Ear

The ear that seen on the side of the head acts like a satellite dish that catches waves of sound. This outer ear is shaped to funnel and swirl the sound of energy made when molecules move as they are displaced by air, water or solid objects. The displacement forms waves that flow into the ear hole. In the tunnel that leads to the ear’s complex structures, the molecules move closer together and become louder.

On to the Middle and Inner Ear

Just about an inch past the ear that is seen outside the body and inside the ear hole, sound energy beats on the ear drum. The rhythm is taken up and passed along by three very tiny bones. In the middle ear compartment, the mechanical action of the bones amplify the air waves.

Now in the form of mechanical energy, the wave moves on to another tiny membrane that leads to the shell-shaped and fluid-filled inner ear. In the shell, called the cochlea, sound energy swims through the fluid and strums across teeny, tiny hairs that bend and snap.

On to the Brain

Energy fires neurons bundled into the nerve of hearing, the auditory nerve. The nerve’s long wires or axons zings energy forward to lower brain structures until the energy in analyzed in the cortex of the brain.

Now, if anything is really magical, it’s this part of hearing. How does that electrical energy get processed into meaningful words and sentences? Researchers are just beginning to understanding how the brain works and new discoveries are revealing more and more amazing information every day.

Sound Traveled, Energy Converted, Hearing Accomplished

Hear that? Fast, wasn’t it?

To summarize, the sound energy from the air is captured by the ear, knocks on the ear drum, is amplified by the bones of the middle ear, swims into the waters of the inner ear where waves wash over tiny hairs, which snap an electrical message along nerve wiring to the brain. The energy zaps to the cortex where analysis takes place and a response unfolds next.

Although it happens in an instant, it’s not magic. But hearing is still rather miraculous … or magical … don’t you agree?