Tag Archives: Adaptive immune system

Immunisation

Definition:
Immunization, or immunisation, is the process by which an individual’s immune system becomes fortified against an agent (known as the immunogen).It  is the process whereby a person is made immune or resistant to an infectious disease.

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Immunization is done through various techniques, most commonly vaccination. Vaccines against microorganisms that cause diseases can prepare the body’s immune system, thus helping to fight or prevent an infection. The fact that mutations can cause cancer cells to produce proteins or other molecules that are known to the body forms the theoretical basis for therapeutic cancer vaccines. Other molecules can be used for immunization as well, for example in experimental vaccines against nicotine (NicVAX) or the hormone ghrelin in experiments to create an obesity vaccine.

Before the introduction of vaccines, the only way people became immune to an infectious disease was by actually getting the disease and surviving it. Smallpox (variola) was prevented in this way by inoculation, which produced a milder effect than the natural disease. It was introduced into England from Turkey by Lady Mary Wortley Montagu in 1721 and used by Zabdiel Boylston in Boston the same year. In 1798 Edward Jenner introduced inoculation with cowpox (smallpox vaccine), a much safer procedure. This procedure, referred to as vaccination, gradually replaced smallpox inoculation, now called variolation to distinguish it from vaccination. Until the 1880s vaccine/vaccination referred only to smallpox, but Louis Pasteur developed immunisation methods for chicken cholera and anthrax in animals and for human rabies, and suggested that the terms vaccine/vaccination should be extended to cover the new procedures. This can cause confusion if care is not taken to specify which vaccine is used e.g. measles vaccine or influenza vaccine.

When this system is exposed to molecules that are foreign to the body, called non-self, it will orchestrate an immune response, and it will also develop the ability to quickly respond to a subsequent encounter because of immunological memory. This is a function of the adaptive immune system. Therefore, by exposing an animal to an immunogen in a controlled way, its body can learn to protect itself: this is called active immunization.

The most important elements of the immune system that are improved by immunization are the T cells, B cells, and the antibodies B cells produce. Memory B cells and memory T cells are responsible for a swift response to a second encounter with a foreign molecule. Passive immunization is direct introduction of these elements into the body, instead of production of these elements by the body itself.

The most important elements of the immune system that are improved by immunization are the T cells, B cells, and the antibodies B cells produce. Memory B cells and memory T cells are responsible for a swift response to a second encounter with a foreign molecule. Passive immunization is direct introduction of these elements into the body, instead of production of these elements by the body itself.

Immunization is a proven tool for controlling and eliminating life-threatening infectious diseases and is estimated to avert between 2 and 3 million deaths each year. It is one of the most cost-effective health investments, with proven strategies that make it accessible to even the most hard-to-reach and vulnerable populations. It has clearly defined target groups; it can be delivered effectively through outreach activities; and vaccination does not require any major lifestyle change.

Immunizations are definitely less risky and an easier way to become immune to a particular disease than risking a milder form of the disease itself. They are important for both adults and children in that they can protect us from the many diseases out there. Through the use of immunizations, some infections and diseases have almost completely been eradicated throughout the United States and the World. One example is polio. Thanks to dedicated health care professionals and the parents of children who vaccinated on schedule, polio has been eliminated in the U.S. since 1979. Polio is still found in other parts of the world so certain people could still be at risk of getting it. This includes those people who have never had the vaccine, those who didn’t receive all doses of the vaccine, or those traveling to areas of the world where polio is still prevalent.

The Immunization can be achieved in an active or passive manner:
Vaccination is an active form of immunization.

Active immunization/vaccination has been named one of the “Ten Great Public Health Achievements in the 20th Century”.

Active immunization:.click & see
Active immunization can occur naturally when a person comes in contact with, for example, a microbe. The immune system will eventually create antibodies and other defenses against the microbe. The next time, the immune response against this microbe can be very efficient; this is the case in many of the childhood infections that a person only contracts once, but then is immune.

Artificial active immunization is where the microbe, or parts of it, are injected into the person before they are able to take it in naturally. If whole microbes are used, they are pre-treated.

The importance of immunization is so great that the American Centers for Disease Control and Prevention has named it one of the “Ten Great Public Health Achievements in the 20th Century”.  Live attenuated vaccines have decreased pathogenicity. Their effectiveness depends on the immune systems ability to replicate and elicits a response similar to natural infection. It is usually effective with a single dose. Examples of live, attenuated vaccines include measles, mumps, rubella, MMR, yellow fever, varicella, rotavirus, and influenza (LAIV).

Passive immunization:……...click & see
Passive immunization is where pre-synthesized elements of the immune system are transferred to a person so that the body does not need to produce these elements itself. Currently, antibodies can be used for passive immunization. This method of immunization begins to work very quickly, but it is short lasting, because the antibodies are naturally broken down, and if there are no B cells to produce more antibodies, they will disappear.

Passive immunization occurs physiologically, when antibodies are transferred from mother to fetus during pregnancy, to protect the fetus before and shortly after birth.

Artificial passive immunization is normally administered by injection and is used if there has been a recent outbreak of a particular disease or as an emergency treatment for toxicity, as in for tetanus. The antibodies can be produced in animals, called “serum therapy,” although there is a high chance of anaphylactic shock because of immunity against animal serum itself. Thus, humanized antibodies produced in vitro by cell culture are used instead if available.

Resources:
http://en.wikipedia.org/wiki/Immunization
http://www.who.int/topics/immunization/en/

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Cholangitis

Definition:
Cholangitis is an infection of the common bile duct, the tube that carries bile from the liver to the gallbladder and intestines. Bile is a liquid made by the liver that helps digest food.

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Cholangitis can be life-threatening, and is regarded as a medical emergency. Characteristic symptoms include yellow discoloration of the skin or whites of the eyes, fever, abdominal pain, and in severe cases, low blood pressure and confusion. Initial treatment is with intravenous fluids and antibiotics, but there is often an underlying problem (such as gallstones or narrowing in the bile duct) for which further tests and treatments may be necessary, usually in the form of endoscopy to relieve obstruction of the bile duct.
Symptoms:
The following symptoms may occur:

*Pain on the upper right side or upper middle part of the abdomen. It may also be felt in the back or below the right shoulder blade. The pain may come and go and feel sharp, cramp-like, or dull.

*Fever and chills

*Dark urine and clay-colored stools

*Nausea and vomiting

*Yellowing of the skin (jaundice), which may come and go
Physical examination findings typically include jaundice and right upper quadrant tenderness.Charcot’s triad is a set of three common findings in cholangitis: abdominal pain, jaundice, and fever. This was assumed in the past to be present in 50–70% of cases, although more recently the frequency has been reported as 15–20%.Reynolds’ pentad includes the findings of Charcot’s triad with the presence of septic shock and mental confusion. This combination of symptoms indicates worsening of the condition and the development of sepsis, and is seen less commonly still.

In the elderly, the presentation may be atypical; they may directly collapse due to septicemia without first showing typical features. Those with an indwelling stent in the bile duct (see below) may not develop jaundice.

Causes:
Cholangitis is most often caused by a bacterial infection. This can occur when the duct is blocked by something, such as a gallstone or tumor. The infection causing this condition may also spread to the liver.

Bile duct obstruction, which is usually present in acute cholangitis, is generally due to gallstones. 10–30% of cases, however, are due to other causes such as benign stricturing (narrowing of the bile duct without an underlying tumor), postoperative damage or an altered structure of the bile ducts such as narrowing at the site of an anastomosis (surgical connection), various tumors (cancer of the bile duct, gallbladder cancer, cancer of the ampulla of Vater, pancreatic cancer, cancer of the duodenum), anaerobic organisms such as Clostridium and Bacteroides (especially in the elderly and those who have undergone previous surgery of the biliary system). Parasites which may infect the liver and bile ducts may cause cholangitis; these include the roundworm Ascaris lumbricoides and the liver flukes Clonorchis sinensis, Opisthorchis viverrini and Opisthorchis felineus. In people with AIDS, a large number of opportunistic organisms has been known to cause AIDS cholangiopathy, but the risk has rapidly diminished since the introduction of effective AIDS treatment. Cholangitis may also complicate medical procedures involving the bile duct, especially ERCP. To prevent this, it is recommended that those undergoing ERCP for any indication receive prophylactic (preventative) antibiotics.

The presence of a permanent biliary stent (e.g. in pancreatic cancer) slightly increases the risk of cholangitis, but stents of this type are often needed to keep the bile duct patent under outside pressure

Diagnosis:
Routine blood tests show features of acute inflammation (raised white blood cell count and elevated C-reactive protein level), and usually abnormal liver function tests (LFTs). In most cases the LFTs will be consistent with obstruction: raised bilirubin, alkaline phosphatase and ?-glutamyl transpeptidase. In the early stages, however, pressure on the liver cells may be the main feature and the tests will resemble those in hepatitis, with elevations in alanine transaminase and aspartate transaminase.

Blood cultures are often performed in people with fever and evidence of acute infection. These yield the bacteria causing the infection in 36% of cases, usually after 24–48 hours of incubation. Bile, too, may be sent for culture during ERCP (see below). The most common bacteria linked to ascending cholangitis are gram-negative bacilli: Escherichia coli (25–50%), Klebsiella (15–20%) and Enterobacter (5–10%). Of the gram-positive cocci, Enterococcus causes 10–20%.

You may have the following tests to look for blockages:

*Abdominal ultrasound

*Endoscopic retrograde cholangiopancreatography (ERCP)

*Magnetic resonance cholangiopancreatography (MRCP)

*Percutaneous transhepatic cholangiogram (PTCA)

*You may also have the following blood tests:

#Bilirubin level
#Liver enzyme levels
#Liver function tests
#White blood count (WBC)
Treatment:
Quick diagnosis and treatment are very important.Antibiotics to cure infection is the first treatment done in most cases. ERCP or other surgical procedure is done when the patient is stable.Patients who are very ill or are quickly getting worse may need surgery right away.

Cholangitis requires admission to hospital. Intravenous fluids are administered, especially if the blood pressure is low, and antibiotics are commenced. Empirical treatment with broad-spectrum antibiotics is usually necessary until it is known for certain which pathogen is causing the infection, and to which antibiotics it is sensitive. Combinations of penicillins and aminoglycosides are widely used, although ciprofloxacin has been shown to be effective in most cases, and may be preferred to aminoglycosides because of fewer side effects. Metronidazole is often added to specifically treat the anaerobic pathogens, especially in those who are very ill or at risk of anaerobic infections. Antibiotics are continued for 7–10 days. Drugs that increase the blood pressure (vasopressors) may also be required to counter the low blood pressure.
Prognosis:
Acute cholangitis carries a significant risk of death, the leading cause being irreversible shock with multiple organ failure (a possible complication of severe infections). Improvements in diagnosis and treatment have led to a reduction in mortality: before 1980, the mortality rate was greater than 50%, but after 1980 it was 10–30%. Patients with signs of multiple organ failure are likely to die unless they undergo early biliary drainage and treatment with systemic antibiotics. Other causes of death following severe cholangitis include heart failure and pneumonia.

Risk Factors:
Risk factors include a previous history of gallstones, sclerosing cholangitis, HIV, narrowing of the common bile duct, and, rarely, travel to countries where you might catch a worm or parasite infection.

Risk factors indicating an increased risk of death include older age, female gender, a history of liver cirrhosis, biliary narrowing due to cancer, acute renal failure and the presence of liver abscesses. Complications following severe cholangitis include renal failure, respiratory failure (inability of the respiratory system to oxygenate blood and/or eliminate carbon dioxide), cardiac arrhythmia, wound infection, pneumonia, gastrointestinal bleeding and myocardial ischemia (lack of blood flow to the heart, leading to heart attacks).

Prevention:
Treatment of gallstones, tumors, and infestations of parasites may reduce the risk for some people. A metal or plastic stent that is placed in the bile system may be needed to prevent the infection from returning.
Disclaimer: This information is not meant to be a substitute for professional medical advise or help. It is always best to consult with a Physician about serious health concerns. This information is in no way intended to diagnose or prescribe remedies.This is purely for educational purpose.
Resources:
http://www.nlm.nih.gov/medlineplus/ency/article/000290.htm
http://en.wikipedia.org/wiki/Ascending_cholangitis

Foe Turns Friend

A-beta, a protein implicated in Alzheimer’s, may be the brain’s shield against germs.
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For years, a prevailing theory has been that one of the chief villains in Alzheimer’s disease has no real function other than as a waste product that the brain never properly disposed of.

The material, a protein called beta amyloid, or A-beta, piles up into tough plaques that destroy signals between nerves. When that happens, people lose their memory, their personality changes and they stop recognising friends and family.

But now researchers at Harvard suggest that the protein has a real and unexpected function — it may be part of the brain’s normal defences against invading bacteria and other microbes.

Other Alzheimer’s researchers say the findings, reported in the current issue of the journal PLoS One, are intriguing.

The new hypothesis got its start late one Friday evening in the summer of 2007 in a laboratory at Harvard Medical School. The lead researcher, Rudolph Tanzi, a neurology professor who is also director of the genetics and aging unit at Massachusetts General Hospital, said he had been looking at a list of genes that seemed to be associated with Alzheimer’s disease.

To his surprise, many looked just like genes associated with the so-called innate immune system, a set of proteins the body uses to fight infections. The system is particularly important in the brain, because antibodies cannot get through the blood-brain barrier, the membrane that protects the brain. When the brain is infected, it relies on the innate immune system to protect it.

That evening, Tanzi wandered into the office of a junior faculty member, Robert Moir, and mentioned what he had seen. As Tanzi recalled, Moir turned to him and said, “Yeah, well, look at this.”

He handed Tanzi a spreadsheet. It was a comparison of A-beta and a well-known protein of the innate immune system, LL-37. The likenesses were uncanny. Among other things, the two proteins had similar structures. And like A-beta, LL-37 tends to clump into hard little balls.

In rodents, the protein that corresponds to LL-37 protects against brain infections. People who make low levels of LL-37 are at increased risk of serious infections and have higher levels of atherosclerotic plaques, arterial growths that impede blood flow.

The scientists could hardly wait to see if A-beta, like LL-37, killed microbes. They mixed A-beta with microbes that LL-37 is known to kill — listeria, staphylococcus, pseudomonas. It killed eight out of 12. “We did the assays exactly as they have been done for years,” Tanzi said. “And A-beta was as potent or, in some cases, more potent than LL-37.”

Then the investigators exposed the yeast Candida albicans, a major cause of meningitis, to tissue from the hippocampal regions of brains from people who had died of Alzheimer’s and from people of the same age who did not have dementia when they died.

Brain samples from Alzheimer’s patients were 24 per cent more active in killing the bacteria. But if the samples were first treated with an antibody that blocked A-beta, they were no better than brain tissue from non-demented people in killing the yeast.

The innate immune system is also set in motion by traumatic brain injuries and strokes and by atherosclerosis that causes reduced blood flow to the brain, Tanzi noted.

And the system is spurred by inflammation. It’s known that patients with Alzheimer’s have inflamed brains, but it hasn’t been clear whether A-beta accumulation was a cause or an effect of the inflammation. Perhaps, Tanzi said, A-beta levels rise as a result of the innate immune system’s response to inflammation; it may be a way the brain responds to a perceived infection. But does that mean Alzheimer’s disease is caused by an overly exuberant brain response to an infection?

That’s one possible reason, along with responses to injuries and inflammation and the effects of genes that cause A-beta levels to be higher than normal, Tanzi said. However, some researchers say that all the pieces of the A-beta innate immune systems hypothesis are not in place.

Dr Norman Relkin, director of the memory disorders programme at New York-Presbyterian / Weill Cornell hospital, said that although the idea was “unquestionably fascinating”, the evidence for it was “a bit tenuous”.

As for the link with infections, Dr Steven DeKosky, an Alzheimer’s researcher at the Virginia School of Medicine, noted that scientists have long looked for evidence linking infections to Alzheimer’s and have come up mostly empty handed.

But if Tanzi is correct about A-beta being part of the innate immune system, that would raise questions about the search for treatments to eliminate the protein from the brain.

“It means you don’t want to hit A-beta with a sledgehammer,” Tanzi said.

But other scientists not connected with the discovery said they were impressed by the new findings. “It changes our thinking about Alzheimer’s disease,” said Dr Eliezer Masliah, who heads the experimental neuropathology laboratory at the University of California, San Diego.

Source : New York Times News Service

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Cancer

Conventional cancer treatments, including surgery, radiation, and chemotherapy, are often highly effective in battling this frightening illness. Gentle natural therapies may be used in conjunction with traditional methods to help curb their troublesome side effects and even boost their potency.

Symptoms
Unusual bleeding or discharge.
A change in either bowel or bladder habits.
Chronic indigestion or difficulty swallowing.
Unexplained increased appetite or weight loss.
A sore that doesn’t heal.
Thickening or lump in the breast, testicles, or elsewhere.
Persistent cough, hoarseness, or sore throat.
A change in a wart or mole.
Unexplained fatigue.

When to Call Your Doctor
If you have any symptom of cancer for two weeks or longer, and there is no other obvious cause.
Reminder: If you have a medical condition, talk to your doctor before taking supplements.

What It Is
There are more than a hundred types of cancer, all marked by uncontrolled growth of abnormal cells. Most begin as solid tumors, from which cancer cells can spread (metastasize) to other parts of the body. Untreated, cancer cells can overpower normal cells and sap the body’s vital nutrients, resulting in grave illness or even death…...click & see

What Causes It
Why healthy cells turn cancerous is unknown. But such factors as smoking, excessive sun exposure, pollutants, stress, and a poor diet appear to play a role. Any of these may weaken the immune system, which is then unable to attack cancer cells effectively, or expose the body to free radicals, unstable oxygen molecules that can damage cells. Heredity also seems to be a key element in the development of many types of cancer.

How Supplements Can Help
In cancer treatment, supplements stir especially intense debate. Studies conflict, and a parade of fraudulent “miracle cures” are offered — usually at a steep price. But a number of supplements, taken daily over the long term, do show special promise as valuable additions to conventional cancer therapies.
Vitamin A, along with the antioxidants vitamin C, vitamin E, carotenoids (especially beta-carotene and lycopene), selenium, and coenzyme Q10, helps protect cells from free radicals and may inhibit the growth of cancerous cells. These supplements may be particularly beneficial for people who have undergone chemotherapy or radiation — procedures that damage healthy cells as they attack cancer cells. Amino acids may speed healing and slow tumor growth as well.

Rotating echinacea in three-week cycles with extracts of medicinal mushrooms and other immune-boosting herbs may help to strengthen overall immunity during cancer treatments. (Vitamin C also bolsters the immune system, aiding it in fighting off any cancer cells remaining in the body after treatment.) The Coriolus versicolor mushroom has shown particular promise against lung, stomach, and colon cancers. Taking a liver detoxification formula (sometimes called a lipotropic combination in health-food stores) to help prevent the buildup of dangerous cancer-promoting toxins in the body may also be a good idea.

What Else You Can Do
Eat a balanced diet, rich in vitamins and minerals.
Join a support group: Studies show this step can prolong your survival.
Try exercise, meditation, biofeedback, massage, or imaging techniques to help reduce stress, lessen anxiety, and ease symptoms.
If nausea is a problem during chemotherapy, try ginger (100 to 200 mg every four hours, or a cup of ginger tea, as needed). Take it with food to avoid stomach irritation. Relaxation tapes or acupuncture may also help.

Supplement Recommendations
Vitamin A
Vitamin C/Vitamin E
Carotenoids
Selenium
Coenzyme Q10
Amino Acids
Echinacea
Mushrooms


Vitamin A

Dosage: 50,000 IU a day for 1 month, then 25,000 IU a day.
Comments: Take only 5,000 IU a day if you may become pregnant.

Vitamin C/Vitamin E

Dosage: 2,000 mg vitamin C 3 times a day; 400 IU vitamin E twice a day.
Comments: Vitamin C helps boost the effects of vitamin E.

Carotenoids
Dosage: 3 pills mixed carotenoids a day with food.
Comments: Each pill should supply 25,000 IU vitamin A activity.

Selenium

Dosage: 200 mcg a day.
Comments: Don’t exceed 600 mcg daily; higher doses may be toxic.

Coenzyme Q10

Dosage: 200 mg each morning.
Comments: For best absorption, take with food.

Amino Acids
Dosage: Mixed amino acids (see label for dosage), plus NAC (500 mg 3 times a day) and L-glutathione (250 mg twice a day).
Comments: Take L-glutathione separately from other amino acids.

Echinacea
Dosage: 200 mg 3 times a day.
Comments: Rotate in 3-week cycles with astragalus (400 mg twice a day), pau d’arco (500 mg twice a day), and mushrooms (below).

Mushrooms
Dosage: 500 mg reishi, 400 mg shiitake, 200 mg maitake 3 times a day; and/or 3,000 mg Coriolus versicolor divided into 2 daily doses.
Comments: Avoid reishi mushrooms if you’re on anticoagulants.

Disclaimer: This information is not meant to be a substitute for professional medical advise or help. It is always best to consult with a Physician about serious health concerns. This information is in no way intended to diagnose or prescribe remedies.This is purely for educational purpose.

Source:Your Guide to Vitamins, Minerals, and Herbs (Reader’s Digest)