porphyria cutanea tarda

Introduction

Porphyria cutanea tarda (PCT) is the most common subtype of porphyria.^[1] The disease is named because it is a porphyria that often presents with skin manifestations later in life. The disorder results from low levels of the enzyme responsible for the fifth step inheme production. Heme is a vital molecule for all of the body's organs. It is a component of hemoglobin, the molecule that carriesoxygen in the blood.

Hepatoerythropoietic porphyria has been described as a homozygous form of porphyria cutanea tarda,^[2] although it can also be caused if two different mutations occur at the same locus.

Signs and symptoms

Porphyria cutanea tarda (commonly referred to as PCT) is recognized as the most prevalent subtype of porphyritic diseases.^[3]

The disease is characterized by onycholysis and blistering of the skin in areas that receive higher levels of exposure to sunlight. The primary cause of this disorder is a deficiency of uroporphyrinogen decarboxylase (UROD), a cytosolic enzyme that is a step in the enzymatic pathway that leads to the synthesis of heme. While a deficiency in this enzyme is the direct cause leading to this disorder, there are a number of both genetic and environmental risk factors that are associated with PCT.^[4]

Typically, patients who are ultimately diagnosed with PCT first seek treatment following the development photosensitivities in the form of blisters and erosions on commonly exposed areas of the skin. This is usually observed in the face, hands, forearms, and lower legs. It heals slowly and with scarring. Though blisters are the most common skin manifestations of PCT, other skin manifestations like hyperpigmentation (as if they are getting a tan) and hypertrichosis (mainly on top of the cheeks) also occur. PCT is a chronic condition, with external symptoms often subsiding and recurring as a result of a number of factors. In addition to the symptomatic manifestation of the disease in the skin, chronicliver problems are extremely common in patients with the sporadic form of PCT. These include hepatic fibrosis (scarring of the liver), cirrhosis, and inflammation. However, liver problems are less common in patients with the inherited form of the disease.^[5] Additionally, patients will often void a wine-red color urine with an increased concentration of uroporphyrin I due to their enzymatic deficiency.^[6]

Health benifits of raw onion

onion... no need of any special intoductioon as it is the very common vegetable that every one of us know...in india day with out onion is impossiable for sure ,it is not ironic to say that even politics in india runs around onion market rates,asa student of science i like even its botany,allium cepa a member of family lilliacae  

it has been enhancing the taste of everyone of our food daily,today let us know some benifits of onion raw one more precisely 

Onions produce the volatile chemical irritant known as syn-propanethial-S-oxide. It stimulates the eyes' lachrymal glands so they release tears. Scientists used to blame the enzyme allinase for the instability of substances in a cut onion.

 daily intake of 35 grams of raw onion along with our food is recommended as it can prevent many entero-gastric diseases,there are as many benifits that we cant count them on fingers

 i have listed few of them below

1. Asthma

Onions have antihistamine effects due to quercetin, an antioxidant that acts like an antihistamine and an anti-inflammatory agent. In test tubes, quercetin has proven to prevent immune cells from releasing histamine, which are chemicals that cause allergic reaction. Based on this observation, researchers believe the antioxidants may reduce histamine, and other allergic or inflammatory chemicals in the body, and can be a promising asthma treatment.

However, no human studies have examined whether it works or not. Stegall believes onions help alleviate asthma because they act as a powerful antioxidant. “Studies have shown that quercetin causes the bronchi of the respiratory tract to widen,” he said.

2. Cancer

Onions can help reduce cancer risk when combined with turmeric. Chemicals found in these two cooking ingredients. A 2006 study published in Clinical Gastroenterology and Hepatologyfound the combination of onions and turmeric creates a synergistic effect that reduces both the size and number of precancerous hosts in the intestine, therefore reducing colon cancer risk. Moreover, Stegall suggests regularly consuming onions can help detoxify potential carcinogens. Since they contain organosulfur compounds. “These compounds are found in the cell wall of the onion, and are released when the onion is chopped or chewed,” he said.

3. Diabetes

A high intake of onions could mean the lower the level of glucose. The essential oil of an onion, allyl propyl disulphide, is found to mediate this effect, and lower blood sugar levels by increasing the amount of free insulin that is available. The allyl propyl disulphide competes with the insulin, which is also a disulphide, to occupy the sites in the liver where the insulin is inactivated. This is what leads to an increase in insulin available, which lowers blood sugar levels. A 1975 study published in the journal Clinica Chimica Acta; International Journal of Clinical Chemistry found onion’s essential oil led to a significant fall in blood glucose levels, and a significant rise in the serum of insulin levels after being administered to six normal volunteers after a 12-hour fast.

4. Heart Disease

When we think of heart healthy food, onions do not come to mind. However, quercetin is found to significantly reduce high blood pressure in hypertensive adults, according to a 2007study published in The Journal of Nutrition. Moreover, this vegetable is considered to exceed the heart-protective properties of red wine. Stegall shared, “Onions are involved in maintaining good blood pressure, inhibit hardening of the arteries, and keep the arteries elastic.”

5. Tooth Decay

Raw onions may make our breath stink, but they can actually improve our oral health. Simply chewing a raw onion can strengthen teeth and eliminate bacteria that can lead to tooth decay. Two to three minutes of chewing on an onion can kill most germs in the mouth, according toNaturalsociety.com.

To stay healthy and prevent the onset of these diseases, eat an onion a day to keep the doctor away.

Remove worms, act as an antibiotic and have antiseptic properties.

Alleviate pains, inflammations and spasms.

Are diuretic, digestive, fungicidal, a tonic and a stimulant.

Lower cholesterol and triglycerides, high blood pressure, reduce risk of heart disease & stroke.

Protect against tumour growths and a wide range of cancers.

Prevents gastric ulcers, stimulates the peristaltic movement of the intestines, removes flatulence & indigestion.

Relieves respiratory problems like cough, cold, flu, bronchitis and remove phlegm.

Are antiallergenic, lower blood sugar levels, maintain strong bones,prevent anaemia and tooth decay and oral infections.

Make the blood thin and retard blood clotting.

COFFEE A DAY RECOMMENDED

   Do  you know the most common sources of caffeine? Well, maybe two of the sources aren't too hard to name -- coffee and tea leaves. But did you know kola nuts and cocoa beans are also included among the most common caffeine sources? And do you know how much caffeine content can vary from food to food? Turns out it's quite a lot actually, depending on the type and serving size of a food or beverage and how it's prepared.

Caffeine content can range from as much as 160 milligrams in some energy drinks to as little as 4 milligrams in a 1-ounce serving of chocolate-flavored syrup. Even decaffeinated coffee isn't completely free of caffeine. Caffeine is also present in some over-the-counter pain relievers, cold medications, and diet pills. These products can contain as little as 16 milligrams or as much as 200 milligrams of caffeine. In fact, caffeine itself is a mild painkiller and increases the effectiveness of other pain relievers.

Caffeine Myth No. 1: Caffeine Is Addictive

This one has some truth to it, depending on what you mean by "addictive." Caffeine is a stimulant to the central nervous system, and regular use of caffeine does cause mild physical dependence. But caffeine doesn't threaten your physical, social, or economic health the way addictive drugs do. (Although after seeing your monthly spending at the coffee shop, you might disagree!)

If you stop taking caffeine abruptly, you may have symptoms for a day or more, especially if you consume two or more cups of coffee a day. Symptoms of withdrawal from caffeine include:

• headache
• fatigue
• anxiety
• irritability
• depressed mood
• difficulty concentrating

No doubt, caffeine withdrawal can make for a few bad days. However, caffeine does not cause the severity of withdrawal or harmful drug-seeking behaviors as street drugs or alcohol. For this reason, most experts don't consider caffeine dependence a serious addiction.

Caffeine Myth No. 2: Caffeine Is Likely to Cause Insomnia

Your body quickly absorbs caffeine. But it also gets rid of it quickly. Processed mainly through the liver, caffeine has a relatively short half-life. This means it takes about five to seven hours, on average, to eliminate half of it from your body. After eight to 10 hours, 75% of the caffeine is gone. For most people, a cup of coffee or two in the morning won't interfere with sleep at night.

Consuming caffeine later in the day, however, can interfere with sleep. If you're like most people, your sleepwon't be affected if you don't consume caffeine at least six hours before going to bed. Your sensitivity may vary, though, depending on your metabolism and the amount of caffeine you regularly consume. People who are more sensitive may not only experience insomnia but also have caffeine side effects of nervousness and gastrointestinal upset.

Caffeine Myth No. 3: Caffeine Increases the Risk of Osteoporosis, Heart Disease, and Cancer

Moderate amounts of daily caffeine -- about 300 milligrams, or three cups of coffee -- apparently cause no harm in most healthy adults. Some people are more vulnerable to its effects, however. That includes such people as those who have high blood pressure or are older. Here are the facts:

• Osteoporosis and caffeine. At high levels (more than 744 milligrams/day), caffeine may increase calcium and magnesium loss in urine. But recent studies suggest it does not increase your risk forbone loss, especially if you get enough calcium. You can offset thecalcium lost from drinking one cup of coffee by adding just two tablespoons of milk. However, research does show some links between caffeine and hip fracture risk in older adults. Older adults may be more sensitive to the effects of caffeine on calciummetabolism. If you're an older woman, discuss with your health careprovider whether you should limit your daily caffeine intake to 300 milligrams or less.
• Cardiovascular disease and caffeine. A slight, temporary rise in heart rate and blood pressure is common in those who are sensitive to caffeine. But several large studies do not link caffeine to highercholesterol, irregular heartbeats, or an increased risk ofcardiovascular disease. If you already have high blood pressure or heart problems, though, have a discussion with your doctor about your caffeine intake. You may be more sensitive to its effects. Also, more research is needed to tell whether caffeine increases the risk for stroke in people with high blood pressure.
• Cancer and caffeine. Reviews of 13 studies involving 20,000 people revealed no relationship between cancer and caffeine. In fact, caffeine may even have a protective effect against certain cancers.

  Caffeine Myth No. 4: Caffeine Is Harmful for Women Trying to Get Pregnant

  Many studies show no links between low amounts of caffeine (a cup of coffee per day) and any of the following:
  • trouble conceiving
  • miscarriage
  • birth defects
  • premature birth
  • low birth rate
  At the same time, for pregnant women or those attempting pregnancy, the March of Dimes suggests fewer than 200 milligrams of caffeine per day. That's largely because in limited studies, women consuming higher amounts of caffeine had an increased risk for miscarriage.

  Caffeine Myth No. 5: Caffeine Has a Dehydrating Effect

  Caffeine can make you need to urinate. However, the fluid you consume in caffeinated beverages tends to offset the effects of fluid loss when you urinate. The bottom line is that although caffeine does act as a mild diuretic, studies show drinking caffeinated drinks in moderation doesn't actually cause dehydration.

  Caffeine Myth No. 6: Caffeine Harms Children, Who, Today, Consume Even More Than Adults

  As of 2004, children ages 6 to 9 consumed about 22 milligrams of caffeine per day. This is well within the recommended limit. However, energy drinks that contain a lot of caffeine are becoming increasingly popular, so this number may go up.
  Some kids are sensitive to caffeine, developing temporary anxiety or irritability, with a "crash" afterwards. Also, most caffeine that kids drink is in sodas, energy drinks, or sweetened teas, all of which have high sugar content. These empty calories put kids at higher risk forobesity.
  Even if the caffeine itself isn't harmful, caffeinated drinks are generally not good for kids.

  Caffeine Myth No. 7: Caffeine Can Help You Sober Up

  Actually, research suggests that people only think caffeine helps them sober up. For example, people who drink caffeine along with alcohol think they're OK behind the wheel. But the truth is reaction time and judgment are still impaired. College kids who drink both alcohol and caffeine are actually more likely to have car accidents.

  Caffeine Myth No. 8: Caffeine Has No Health Benefits

  Caffeine has few proven health benefits. But the list of caffeine's potential benefits is interesting. Any regular coffee drinker may tell you that caffeine improves alertness, concentration, energy, clear-headedness, and feelings of sociability. You might even be the type who needs that first cup o' Joe each morning before you say a single word. Scientific studies support these subjective findings. One French study even showed a slower decline in cognitive ability among women who consumed caffeine.
  Other possible benefits include helping certain types of headache pain. Some people's asthma also appears to benefit from caffeine. These research findings are intriguing, but still need to be proven.
  Limited evidence suggests caffeine may also reduce the risk of the following:
  • Parkinson's disease
  • liver disease
  • colorectal cancer
  • type 2 diabetes
  • dementia
  Despite its potential benefits, don't forget that high levels of caffeine may have adverse effects. More studies are needed to confirm both its benefits and potential risks.