Sunday, April 29, 2007

A Museum for the Morbid

I'm in the process of writing a post on the next major disease - Alzheimer's - but in the meantime I thought I'd introduce you to a fascinating museum in Philadelphia, the Mutter Museum. That's Mutter with those little dots over the "u" (umlaut I believe it's called!).

I hadn't heard of the Mutter Museum until my Dear Husband gave me a marvelous book about it for Christmas one year.

The museum is a part of the College of Physicians of Philadelphia, and was founded in 1858 as a repository for medical oddities to help educate the budding physicians at the college and enlighten them about human anatomy and anomalies.

As described on the College's website, the museum was founded by Thomas Dent Mütter, retired Professor of Surgery at Jefferson Medical College. He donated his own collection of specimens to The College of Physicians of Philadelphia.

The collection comprises over 20,000 objects, including fluid-preserved anatomical and pathological specimens; skeletal and dried specimens, medical instruments, memorabilia of famous scientists and physicians; medical illustrations, photographs, prints, and portraits.

The objects displayed include:

The plaster cast of the torso of world-famous Siamese Twins, Chang & Eng, and their conjoined livers (yes, their ACTUAL livers);
Joseph Hyrtl's collection of skulls;
Preserved body of the "Soap Lady";
Collection of 2,000 objects extracted from people's throats;
Cancerous growth removed from President Grover Cleveland;
and the tallest skeleton on display in North America (7' 6").

You may think I might not have appreciated my husband for having chosen a book about this museum as a gift for me. You would be wrong. Being the hypochondriac and medical junkie I have always been, I loved it. It was my favorite Christmas present out of the past decade!

As a child I used to find medical books in my parents' bookcases since they were both medical writers. I reveled in paging through these tomes, which came with photographs of people with bizarre diseases and deformities. The pictures considerately had black bars across the eyes on the faces of the unfortunate sufferers so no one would guess their identities. The Mutter Museum photography book was right up my alley.

The book includes photographs of many of the most grotesque exhibits from the museum, including the liver of Chang and Eng, mentioned above. There is a woman with a horn sticking out of her head. (Yes, people really do develop these things). And there are even photos by the famous photographer William Wegman, known for his trademark photographs of Weimaraners.

I have not yet visited the Mutter Museum but intend to do so at some point, sooner rather than later!

Thursday, April 19, 2007

Medical Knowledge - Practice Makes Perfect

Since I am between major articles I decided to post another useful site for you. Instead of letting you go searching for symptoms, this site will let you test your medical knowledge and make sure you are up to date on your medical terminology.

It is a listing of quizzes pertaining to medical subjects. Some are easy, others are more difficult.

Test your knowledge - see if you can qualify to be a professional hypochondriac or whether you are strictly amateur!

Sunday, April 15, 2007


Distribution of Lymphatic Filiaris in the world

So far I have tended to write about diseases or conditions that have affected either me or someone I know. And this topic is no exception. Well, the condition of Elephantiasis itself did not affect anyone I know, but a friend of mine has a daughter who saw something about the disease on Discovery channel last year and started to worry that she might have it! (My friend and I joke that her daughter is really my blood relative since she has my same tendency to be a hypochondriac!)

Her daughter, who was about 9 or 10 at the time, started focusing on her hands and imagining they were growing. Luckily her mother was finally able to convince her there was nothing wrong with her, and she hasn't had any other health-related panics in recent months! I can so identify with this because it is exactly the kind of thing I used to do...fixate on some symptom and keep checking to see if it was still there.

So, Elephantiasis. It's actually NOT what the famous "Elephant Man" (Joseph Merrick) had. He apparently suffered from something called Proteus Syndrome, not elephantiasis as experts had thought during his lifetime, and not neurofibromatosis, as was postulated in the 1970's.

What is it?

The main type of Elephantiasis, also called Lymphatic Filariasis, is a parasitic disease that is endemic in 80 countries throughout the world, and about 120 million people are directly affected. The disease flourishes in tropical and subtropical areas, including India, Africa, South Asia, the Pacific and the Americas.

Caused by tiny threadlike worms called Wuchereria bancrofti and Brugia malayi that invade the human lymphatic system (the system of lymph nodes and fluid that are the main system for the body to defend itself against disease), Elephantiasis causes enlargement of the leg, arm, genitals, vulva and breasts. The worms live for 4-6 years and produce millions of larvae that are released into the blood. Mosquitoes that bite an infected person pick up the larvae from the blood and are then able to transmit them to another person after the larvae continue to incubate for 1-3 weeks within the mosquito.

The disease has been increasing in prevalence in recent years due to the unplanned growth of cities in the developing world. The cities provide even more places for the mosquitoes to breed and multiply.

Men are more likely to be affected than women; 10-50% of men in affected populations can be symptomatic, and up to 10% of women.

The parasitic form of the disease is not the only type. Since the enlargement of certain body parts is because of swelling due to a build-up of fluid from a blocked lymphatic system, there can be other causes as well.

Nonfilarial elephantiasis, the second type of elephantiasis, is more common in Africa’s central mountains. It is caused by contact with volcanic ash in the soil; since the population mainly goes barefoot, the chemicals from the soil leach into their feet and eventually irritate and block the lymphatic vessels.

Hereditary lymphedema is a disorder caused by a genetic defect, which causes an accumulation of fluid to collect in the affected parts of the body. Underdevelopment of the lymph vessels is thought to be the cause.

What are the symptoms?

The obstruction of the lymphatic vessels results in extreme swelling of the skin and tissues, typically in the lower trunk and body. It primarily affects the legs and genitals, resulting in baggy, thickened and ulcerated skin, along with fever and chills. One serious complication of elephantiasis can also be obstructed blood vessels, which limit blood supply and cause the skin to become infected and can even lead to gangrene.

In the parasitic form of the disease, symptoms of elephantiasis may not appear until years after infection. As the parasites build up in the blood vessels, they restrict circulation and cause fluid to accumulate in surrounding tissues.

Symptoms of infection with elephantiasis are:

Pain in/above testicles (for men only of course)
Enlarged groin lymph nodes
Massively swollen legs, genitalia and breasts
White urinary discharge
Swollen liver
Swollen spleen

How is it diagnosed?

Until recently it was hard to definitively diagnose the parasitic form of the disease. The worms' active period is at night so blood samples taken during the day did not always show any activity. Now, however, there is a simple test that looks for the antigens to the parasites in the blood rather than the parasites themselves, and it is able to be diagnosed with a finger-prick blood test.

How is it treated?

There are medications that remove the parasites from the blood, which helps prevent transmission of the disease. DEC (diethylcarbamazine) reduces the number of parasites from the blood of an infected person for a year; a single dose of two drugs given together (albendazole with DEC or ivermectin) is 99% effective in removing the parasites from the blood for one full year.

Both albendazole and DEC have been shown to be effective in killing the adult-stage filarial parasites (which would accomplish a complete cure of infection), but an ideal treatment protocol has not yet been defined. Eliminating the parasites can help improve the symptoms, especially if the patient is still in the early stages.

Other medications include Suramin, Metrifonate, Mebendazole and Levamisole. Recent studies of use of the antibiotic doxycycline show promise. Medicines must be taken early after the primary infection. The problem with treatment of elephantiasis is that it is difficult to diagnose it early enough for the treatment to prevent the disabling effects of the disease.

Many of the most bothersome symptoms come from secondary bacterial and fungal infections caused by the original infection with the worms. Keeping the affected areas of the body very clean and taking care to minimize infection and encourage lymph flow are important in reducing the frequency of fevers and symptoms of elephantiasis.

Surgery is sometimes used to remove the excess tissue and fluid if possible.

The World Health Organization is working to stop the spread of Elephantiasis by treating the affected populations for the infection and disseminating table salt with DEC in it to keep the level of parasites down.

Control of mosquitoes in the areas where the disease is endemic would also be an important component in eradicating the disease.

Will you get it?

You might if you travel to an area where it is endemic, and newcomers develop symptoms more quickly than populations that have lived with the disease for many years. There is no vaccine currently available. To prevent infection, be sure to wear mosquito repellent and stay covered up wherever mosquitoes are prevalent. If you are in a tropical location sleep with mosquito netting around your bed.

Other sources for this post:

Sunday, April 8, 2007

Lung Cancer

I've known three people with lung cancer. Although lung cancer usually has a poor prognosis, two of the three people survived it. The third is still alive, although her long-term outlook is poor.

One of the three was diagnosed early on with an operable cancer and it was surgically removed. Luckily because it was caught early and he was treated at Memorial Sloan Kettering, he recovered. A cigarette smoker, he quit after his diagnosis, although I believe he eventually went back to smoking cigars or pipes.

The other is the mother of a friend of mine. She was diagnosed with Stage IIIb (more on staging later, but just know this is not good) lung cancer at age 69, after having quit smoking five years earlier. My friend was diligent in researching her mother's condition and combined state of the art medical treatment with alternative medicine for her mother, who has now been cancer free for over eight years.

The third person, the sister of a good friend of mine, has not been so fortunate. She waited too long to go to the doctor, despite knowing she had concerning symptoms, and by the time she was diagnosed, the cancer had spread to her brain and bones, and the tumor in her lung was inoperable. However, with chemotherapy and radiation, she has already lived longer than the expected 18 months and has been able to enjoy time with her daughter and other family members.

So, although lung cancer is often fatal, it doesn't have to be. And early diagnosis can make a difference. Because they are typically diagnosed at a later stage of disease, 6 in 10 lung cancer patients will die within the first year following diagnosis. Five-year survival is just 14 percent, and an estimated 170,000 Americans die each year from the disease. As a result, lung cancer is the leading cause of death due to cancer in both men and women in the United States.

What is lung cancer?

There are two major varieties of lung cancer: primary and metastatic. The metastatic kind is actually other types of cancer that have spread to the lungs. So although it is in the lungs, it is actually cells from the other type of cancer. This article is going to focus on the primary type, that originates in the lungs.

There are different types of primary lung cancer. The two major classes of lung cancer are: Small cell lung cancer and non-small cell lung cancer. (Strangely, they don't call the non-small cell lung cancer, "large cell lung cancer" - that's because a specific type of non-small cell lung cancer is called "large cell lung cancer.")

Small cell lung cancer only makes up 20% of all lung cancers, and it is the cancer most closely tied to smoking. This type, also known as "oat cell cancer," spreads rapidly to other sites in the body and is quite aggressive.

Non-small cell lung cancer grows more slowly and does not spread as aggressively as non-small cell lung cancer.

Non-small cell lung cancer (NSCLC) comes in three main varieties:

Adenocarcinomas are the most common type of NSCLC in the U.S. and account for up to 50% of NSCLC . Although these tumors are still associated with smoking, this type is the one most seen in non-smokers who develop lung cancer.

Squamous cell carcinomas presently account for about 30% of NSCLC. Also known as epidermoid carcinomas, they arise most frequently in the central chest area in the bronchi. This is really just like having skin cancer in your lung.

Large cell carcinomas, sometimes referred to as "undifferentiated carcinomas," are the least common type of NSCLC.

Mixtures of different types of NSCLC are also seen.

There are other miscellaneous types of lung cancer than NSCLC and SCLC, and together they account for about 5-10% of lung cancers:

Bronchial carcinoids are the main remaining type, and account for up to 5% of lung cancers. These tumors are usually small when diagnosed and occur most commonly in people under 40. This type is not related to cigarette smoking. They can metastasize, and a small proportion of these tumors secrete hormone-like substances. Carcinoids generally grow and spread more slowly and are detected early enough to be operable.

What causes lung cancer?

Smoking is the main co-factor causing lung cancer in most people who get it; in fact, approximately 87% of all lung cancers are caused by smoking. And, although if you are a smoker and you quit, the risk of lung cancer declines each year, it never returns to pre-smoking levels. There tends to be a 20-year lag time from the time smoking began to the time cancer develops.

(Chart copyright © 2005 BIOTECH100.COM. All rights reserved)

Secondhand cigarette smoke can also cause lung cancer in non-smokers, as can inhaling radon gas. Exposure to asbestos causes a specific type of lung cancer called mesothelioma. There are other inhaled carcinogens that can cause lung cancer as well. It is theorized that viruses can even be involved in some cases.

We all know plenty of people who have smoked like chimneys all their lives and have no sign of lung cancer; my mother, for instance. She is now 88 years old and has been smoking a pack of cigarettes a day for 60 years and is doing fine. Then there are others who didn't even smoke that long, or never smoked at all, and nevertheless get lung cancer. So, most people who get lung cancer are smokers, but not all smokers get lung cancer. Why is this?

Recent research indicates that those who get lung cancer are more apt to have a variation in a gene that produces an enzyme that protects against lung cancer, resulting in lower levels of the enzyme, making them more susceptible to cancer. An Israeli study also identified an enzyme that may be lacking in lung cancer victims, so there may be several co-factors involved. As more is understood about these co-factors, new drugs may become available. There are even studies that indicate ACE inhibitors, a type of blood pressure drug, may help protect against lung cancer.

In the past, men were more apt to get lung cancer than women, but in recent years the rate of lung cancer in men has been dropping, but it is still rising in women. This may reflect the differences in prevalence of smoking in men vs. women over the years.

If you want to prevent lung cancer, don't smoke. If you do smoke, quit. You don't know whether you're one of the people who have the genetic tendency to get lung cancer or not; why take a chance?

Avoid exposure to toxins and carcinogens; have your home tested for radon and stay away from places that expose you to second-hand smoke. Now that so many states have passed laws against smoking in the workplace and in other public places, this should be less of a problem than in the past.

There is now evidence that eating cruciferous vegetables such as cauliflower and broccoli may help prevent or inhibit lung cancer:

What are the symptoms?

OK, so say you're a smoker or an ex-smoker and are worried about lung cancer. What symptoms should you be on the lookout for? What can you do to make sure you catch it early if you do get it?


  • Chronic cough
  • Coughing up blood
  • Hoarseness
  • Weight loss and loss of appetite
  • Shortness of breath
  • Fever without any reason to have one
  • Wheezing
  • Repeated episodes of bronchitis or pneumonia
  • Chest pain
In about a quarter of lung cancer cases, the cancer is discovered early, through an X-ray or CT scan, and the patient has not had any symptoms whatsoever.

Once symptoms start, this indicates the cancer is large enough to interfere with the esophagus, the vocal chords, the lungs, or even the nerves (causing shoulder pain for some).

Further symptoms can develop due to metastasis of the original tumor, as happened to my friend's sister. Lung cancer that has spread to the bones can cause pain at the sites of bone involvement, e.g., pain in the ribs, if the ribs are affected. Cancer that has spread to the brain may cause blurred vision, headaches, seizures, or weakness or loss of sensation in parts of the body.

Lung cancers are often accompanied by "paraneoplastic syndromes," symptoms that are caused by production of hormone-like substances by the tumor cells. This occurs most often with SCLC but may be seen with any tumor type. Sometimes this syndrome causes too much of the hormone cortisol to be produced by the adrenal glands (Cushing’s Syndrome). The most frequent paraneoplastic syndrome seen with NSCLC is the production of a substance that causes elevated levels of calcium in the bloodstream.

Other less specific symptoms can also be apparent: weakness, tiredness, depression.

How is it diagnosed?

First, the doctor will take a full history of your symptoms, smoking habits, and anything else that might be pertinent. Physical examination may reveal sounds in the lungs or other symptoms ("clubbing" of the fingernails can indicate lung disease; pallor or a bluish tinge to the skin can show lack of oxygen).

A chest X-Ray will often be taken. Some doctors may do a "spiral CT" scan which is more sensitive than an X-Ray; unfortunately it also often shows nodules that turn out to be benign but require further testing to make sure.

An MRI (magnetic resonance imaging) can provide more detailed information about a tumor's location in the body.

Positron emission tomography (PET) scanning is a specialized imaging technique that uses short-lived radioactive substances to produce three-dimensional colored images of those substances functioning within the body. PET scans measure metabolic activity and functioning of tissue and can tell whether a tumor is actively growing and can help identify the type of cells within a particular tumor.

Bone scans using radioadtive material are done to determine whether the cancer has spread to the bones as part of the staging process.

Even if one of the scans shows a possible tumor, unless cancer cells are observed under a microscope, no one can be sure whether it is cancer or not.

Often just examining the patient's sputum under a microscope can enable a pathologist to make a diagnosis, as the cancer cells can often be seen in the sputum.

A more direct method to obtain cells is to biopsy the affected area of the lungs with an instrument called a bronchoscope, a thin tube that is put down into the patient's lungs to look at and sample the suspected tumor. This is done with the patient under sedation, in an outpatient procedure.

For tumors not reachable through a brochoscopy, fine needle aspiration of nodules that have been identified through a scan can be done, by inserting a very thin needle through the chest wall into the lungs.

If fluid has accumulated in the lining of the lungs, as can happen with certain types of lung cancer, then this fluid can be aspirated with a needle and examined for cancer cells as well.

Blood tests are also done to see if any abnormalities show up that could be caused by the cancer.

Once all these tests are complete and lung cancer has been definitively diagnosed, the physician can then stage the cancer, which identifies how far the cancer has spread and helps guide treatment options and prognosis.

Staging involves both evaluation of a tumor’s size as well as the presence or absence of metastases in the lymph nodes or in other organs.

Non-small cell lung cancers are assigned a stage from I to IV in order of severity:

  • Stage I: The cancer is confined to the lung.
  • Stages II and III, the cancer is confined to the chest (with larger and more invasive tumors classified as stage III).
  • Stage IV: Cancer has spread to other parts of the body.

Small cell lung cancers are staged using a simpler system:

  • Limited stage (LS) SCLC: Cancer that is confined to its area of origin in the chest.
  • Extensive-stage (ES) SCLC: Cancer has spread beyond the chest to other parts of the body.

There are also more complex ways that doctors use to stage lung cancer, described in this link: As you'll see, my friend's mother's Stage IIIb cancer meant some lymph node involvement, but thankfully, no distant metastases.

How is it treated?

Depending on the stage and location of the tumor, it may be treated by surgery, radiation, chemotherapy, or all three.

Surgery - Surgical removal of the tumor is the treatment of choice for cancer that has not spread beyond the lung. Unfortunately, only about 10-35% of lung cancers can be removed surgically, and even then removal does not always result in a cure, since the tumors may already have spread and can come back later on.

Among people who have an isolated, slow-growing lung cancer removed, 25 to 40% are alive 5 years after diagnosis.

Surgery may not be possible if the cancer is too close to the windpipe or there are health problems that would endanger the patient if an operation were performed. Surgery is less often performed with SCLC because these tumors are less likely to be localized to one area.

It is a nasty operation. Surgeons have to cut open the chest wall and may have to remove a portion of one lobe of the lung, perform a full lobectomy (removal of the whole lobe), or a pneumonectomy (removal of an entire lung). Sometimes lymph nodes in the region of the lungs are also removed. The risks of surgery include complications due to bleeding, infection, and complications of general anesthesia, and the patient must be carefully followed afterward as he or she recovers from the surgery.

Radiation - Radiation therapy may be used as a treatment for both NSCLC and SCLC. Radiation therapy may be given as curative therapy, palliative therapy (just to help reduce symptoms, by using lower doses of radiation than with curative regimens) or as an accompaniment to surgery or chemotherapy. The radiation is either delivered by using a machine that directs radiation toward the cancer, or internally through placement of radioactive substances in the area of the tumor.

Radiation therapy can be given without surgery if a tumor is inoperable, or if a person has other conditions that make them too ill to undergo major surgery. Radiation therapy generally only shrinks a tumor or limits its growth when given as a sole therapy, yet in 10-15% of persons it leads to long-term remission and palliation of the cancer. Combining radiation therapy with chemotherapy can further increase the chances of survival. External radiation therapy can generally be carried out on an outpatient basis while internal radiation therapy requires a brief hospitalization.

Radiation therapy can cause tiredness, lack of energy, reduced white cell count and low blood platelet levels. It may also cause nausea, vomiting, or diarrhea.

For patients with inoperable tumors, radiofrequency ablation can be very effective.

Chemotherapy - Both NSCLC and SCLC may be treated with chemotherapy. The platinum-based drugs have been the most effective in treatment of lung cancers.

Chemotherapy is the best treatment for most small cell lung cancers, since these tumors are generally widespread in the body when they are diagnosed. Only half of people who have SCLC survive for four months without chemotherapy. With it, their survival time is increased up to four or five times that long.

Chemotherapy alone is not particularly effective in treating NSCLC, but when NSCLC have metastasized it can prolong survival.

Chemotherapy may be given as pills, as an intravenous infusion, or as a combination of the two, and are usually done on an outpatient basis. A combination of drugs is given in a series of treatments, called cycles, over a period of weeks to months, with breaks in between cycles. The blood must be checked for levels of platelets and white blood cells; when they get too long, a cycle may have to be missed.

There is a new drug, Tarceva, which has been shown to prolong life in lung cancer patients.

Side effects to most chemotherapy include increased susceptibility to infections and difficulties with blood clotting (bleeding or bruising easily), fatigue, weight loss, hair loss, nausea, vomiting, diarrhea, and mouth sores. Medications have been developed that can treat or prevent many of the side effects of chemotherapy, so it is not as unpleasant as it was in the past.

Sometimes people with SCLC that is responding well to treatment are treated with radiation therapy to the head to treat very early spread to the brain (called micrometastasis) that is not yet detectable with CT or MRI scans and has not yet produced symptoms.

Lung cancer that has returned following treatment with surgery, chemotherapy, and/or radiation therapy is called recurrent or relapsed. If a recurrent cancer is confined to one site in the lung, it may be treated with surgery. Relapsed tumors are usually resistant to the original type of chemotherapy that was used. So, a second-line chemotherapy is used to treat recurrent cancers, and some of these agents have been proved effective at prolonging survival.

New drugs or new combinations of drugs are tested in clinical trials, studies that evaluate the effectiveness of new medications in comparison with those treatments already in widespread use. If you have a lung tumor with a poor prognosis, you may want to check some of these out ahead of time before starting treatment. Depending on the protocol of the clinical trial, some may require that you have not undergone previous treatment before participating in a trial. Refer to the National Cancer Institute's website to find a clinical trial:

Treatments known as immunotherapies are being tested. These may involve the use of vaccine-related therapies or other therapies that attempt to utilize the body’s immune system to fight cancer cells.

One kind of experimental therapy used for recurrent SCLC is photodynamic therapy, in which a photosynthesizing agent (such as a porphyrin, a naturally-occurring substance in the body) is injected into the bloodstream a few hours prior to surgery. During this time, the agent deposits itself selectively in rapidly growing cells such as cancer cells. A surgical procedure then follows in which the physician applies a certain wavelength of light through a hand held wand directly to the site of the cancer and surrounding tissues. The energy from the light activates the photosensitizing agent, causing the production of a toxin that destroys the tumor cells.

Small cell lung cancer is the most aggressive; it has a median survival time of only 2-4 months after diagnosis when untreated. But, there is some hope: SCLC is also the most responsive to radiation therapy and chemotherapy. Nevertheless, of all patients with SCLC, only 5-10% are alive 5 years after diagnosis.

As for non-small cell lung cancer (NSCLC), in Stage I cancers that can be completely removed, the 5-year survival rate is nearly 75%. Radiation therapy can produce a cure in a small minority of patients with NSCLC and relief of symptoms in most patients. In advanced-stage disease, chemotherapy can improve survival time; however, overall survival rates are still poor.

Survival rates for lung cancer are generally lower than those for most cancers, with an overall 5-year survival rate for lung cancer of about 15%.

Sounds bad. What about alternative therapies?

There are a number of alternative therapies out there that many people swear have helped them or a loved one. This website offers a good summary of a number of promising alternative therapies, as well as information on which therapies may interfere with other treatments:

The National Cancer Institute also offers a comprehensive overview of alternative therapies and how they are testing them:

There are some controversial alternative therapies out there. My friend's mother took a substance called hydrazine sulfate. This National Cancer Institute link explains the history of its use and the tests that have been done: The controversy arises because, according to Dr. Joseph Gold, the main proponent of the use of hydrazine sulfate, the clinical trials that were done did not follow his recommended protocol and therefore he felt that the trials were invalid. Studies in Russia and elsewhere seem to show a benefit. I have no idea whether my friend's mother would have lived anyway without the hydrazine sulfate. But I do know that WITH it, she did live. And it's also an antidepressant, which can't hurt when you have cancer.

My recommendation is, if you are diagnosed with lung cancer, do your research. Go on line, read legitimate medical sites, learn about new clinical trials, question your doctors. Always get a second opinion in the beginning and make sure you go to a major cancer center for all of your treatments, including the initial diagnosis and operation, if any. If you do decide to take alternative medicines, be sure to keep your doctors informed of everything you are taking.

Will you get lung cancer?

If you don't smoke, and haven't been exposed to carcinogenic chemicals or substances, probably not.

Men are still more likely to get it (78.5 per 100,000 men vs. 51 per 100,000 women), but as previously mentioned, their rates are declining while women's are increasing.

Sources for this information in addition to links noted above, were: