The thorn on a rose stem provides an excellent device for injecting infectious material into your skin. Any of the treatments you use in your garden for the health of your roses can provoke an inflammatory reaction when injected by a scratch or prick. So can various bacteria and simple dirt.

Megacolon is a condition in which the colon is abnormally dilated in a short space of time. Toxic substances build up in the intestines and can cause bowel perforation. In children, megacolon can be caused by several underlying conditions including Hirschprung's disease, Inflammatory Bowel Disease and constipation.

Very few people experience allergic reactions to dental fillings, according to the American Dental Association. An allergy is an immune system reaction to a foreign substance. People with allergies to the materials used to make dental fillings may experience a localized reaction.

Melanin is a compound derived from the amino acid, tyrosine. It provides pigment to most animals, including humans. In people, melanin determines skin color. People with high amounts of melanin tend to have darker skin, whereas people with less melanin have lighter skin.

Ghee is an Indian butter that is used for cooking. Ghee contains little to no lactose, according to DrGourmet.com. If you’re lactose intolerant, you should not experience any symptoms after eating ghee. Ghee is not commonly used in large quantities and does not naturally contain a significant amount of lactose.

Chickenpox is an infectious disease caused by the varicella virus, with symptoms typically including an itchy, blister-like rash, fever and headache. While most cases occur in children under 15, adults who don't have immunity to the varicella virus also can contract chickenpox.

Esophageal narrowing can cause malnutrition, breathing problems and death. Throat stretching is a life-saving procedure that can help with this condition. Knowing how the procedure is performed and the benefits it has to offer can help you decide if throat stretching is right for you.

According to the National Institute of Mental Health, bipolar disorder is a severe mental illness that affects 5.7 million adults in the United States. Bipolar patients display symptoms of severe highs that are manic in nature. The disease can shift to a deep depression, causing mood instability and uneven temperament.

You may hear the word "bacteria," and shudder, thinking of the bacteria that can cause sickness and the spread of illness. But not all bacteria is bad. In fact, some bacteria is necessary for us to live, eat, work and feel healthy.

Proper nutrition is the foundation of optimum health and certain vitamins can play a vital role in combating stress, fatigue and mood swings. According to Healthy.net, the right vitamins may help to stimulate your immune system, glands and digestive tract, while stabilizing your mood.

Mucus is a slimy, slippery fluid that acts as a lubricant and protects various structures in the body. There are a number of mucus-secreting cells in the body, but mucus is most prominent in the respiratory, genital and gastrointestinal tracts, notes the University of Colorado at Boulder.

A wide array of factors can trigger heart palpitations, a sensation that the heart is racing, pounding or even missing a beat. Causes may include anxiety, fear, stress, anemia, some medications and street drugs, hyperthyroidism, fever and heart valve disease.