(Malay) Osteogenesis imperfecta (OI dan kadang-kadang dikenali sebagai penyakit tulang rapuh, atau "Lobstein syndrome"[1]) adalah gangguan tulang genetik. Mereka dengan keadaan OI dilahirkan dengan tisu penghubung cacat, atau tanpa keupayaan untuk membinanya, biasanya kerana kekurangan kolagen Jenis I. kekurangan ini timbul akibat penggantian asid amino glycine pada asid amino lebih besar dalam struktur kolagen tiga helik. Rantaian sisi asid amino yang lebih mewujudkan halangan sterik yang membentuk bonjol di binaan kolagen, yang seterusnya mempengaruhi kedua-dua molekul nanomekanikal serta tindak balas antara molekul, yang kedua-dua terjejas. Akibatnya, badan boleh bertindak balas dengan hidrolising struktur kolagen yang tidak sempurna. Jika badan tidak memusnahkan kolagen yang tidak sempurna, hubungan antara gentian halus kolagen dan kristal hidroksiapatit untuk membentuk tulang berubah, menyebabkan kerapuhan. Satu lagi mekanisme penyakit yang dicadangkan ialah bahawa keadaan tegasan di gentian halus kolagen berubah di lokasi mutasi, di mana daya ricih ("shear forces") tempatan yang lebih besar mendorong kepada kegagalan pesat gentian halus walaupun pada beban yang sederhana sebagai keadaan tekanan homogen yang berlaku dalam gentian halus kolagen sihat. Penyeidikan baru ini mencadangkan bahawa OI perlu difahami sebagai suatu fenomena skala-besaran, yang membabitkan mekanisme di peringkat genetik, nano, mikro dan makro-tisu.
Sebagai gangguan genetik, OI dalam sejarah telah telah dilihat sebagai gangguan autosomal dominanpada kolagen Jenis I. Dalam beberapa tahun yang lalu, bentuk resesif autosom telah dikenal pasti. Kebanyakan mereka dengan OI mewarisinya dari ibu atau bapa tetapi dalam 35% kes-kes itu merupakan seorang individu dengan mutasi
(English) Osteogenesis imperfecta (OI and sometimes known as brittle bone disease, or "Lobstein syndrome" is a congenital bone disorder. People with OI are born with defective connective tissue, or without the ability to make it, usually because of a deficiency of Type-I collagen.[2] This deficiency arises from an amino acid substitution of glycine to bulkier amino acids in the collagen triple helix structure. The larger amino acid side-chains create steric hindrance that creates a bulge in the collagen complex, which in turn influences both the molecular nanomechanics as well as the interaction between molecules, which are both compromised.[3] As a result, the body may respond by hydrolyzing the improper collagen structure. If the body does not destroy the improper collagen, the relationship between the collagen fibrils and hydroxyapatite crystals to form bone is altered, causing brittleness.[4] Another suggested disease mechanism is that the stress state within collagen fibrils is altered at the locations of mutations, where locally larger shear forces lead to rapid failure of fibrils even at moderate loads as the homogeneous stress state found in healthy collagen fibrils is lost.[3] These recent works suggest that OI must be understood as a multi-scale phenomenon, which involves mechanisms at the genetic, nano-, micro- and macro-level of tissues.
As a genetic disorder, OI has historically been viewed as an autosomal dominant disorder of type I collagen. In the past several years, there has been the identification of autosomal recessive forms.[citation needed] Most people with OI receive it from a parent but in 35% of cases it is an individual (de novo or "sporadic") mutation.
1. Rawatan (Medication)
Although there is no cure for osteoporosis, the following medications are approved by the FDA for postmenopausal women to prevent and/or treat osteoporosis:
Bisphosphonates: Alendronate (brand name Fosamax®) and Risedronate (brand name Actonel®)
Calcitonin (brand name Miacalcin®)
Estrogen/Hormone Therapy:
Estrogens (brand names, such as Climara® Estrace®, Estraderm®, Estratab®, Ogen®, Ortho-Est®, Premarin®, Vivelle®, and others)
Estrogens and Progestins (brand names, such as Activella™, FemHrt®, Premphase®, Prempro®, and others)
Parathyroid Hormone: Teriparatide (PTH (1-34), brand name Fortéo®)
Selective Estrogen Receptor Modulators (SERMs): Raloxifene (brand name Evista®)
Alendronate is approved as a treatment for osteoporosis in men and is approved for treatment of glucocorticoid (steroid)-induced osteoporosis in men and women. Risedronate is approved for prevention and treatment of glucocorticoid-induced osteoporosis in men and women.
Parathyroid hormone is approved for treatment of osteoporosis in men who are at high risk of fracture.
Treatments under investigation include sodium fluoride, vitamin D metabolites, and other bisphosphonates and selective estrogen receptor modulators.
References:
The NIH Osteoporosis and Related Bone Diseases ~ National Resource Center
2. Herbals atau Nutritional and Herbal Therapy for Osteoporosis
Calcium (1,000 mg a day, but should be increased for osteoporosis) is extremely important. If your blood levels are low in this mineral, calcium will be taken from your bones in order give the muscles and nerves the amount they need.
Vitamin D is needed in order to absorb calcium.
Magnesium (500 mg a day) helps convert Vitamin D into its usable form.
Vitamin K is essential for bone mineralization. Low levels are associated with low bone density.
Isoflavone has a positve effect on bone metabolism.
Vitamins B12 and B6, folic acid keep homecysteine levels down, which has been linked to osteoporosis risk
Dura-Bone is an excellent supplement to strengthen bones and tendons and help stave off osteoporosis.
3. Diet
Calcium and Bone Health
Calcium does not improve the basic collagen defects that cause OI. Even so, people with OI need to get adequate calcium in their diets to develop peak bone mass and prevent bone loss. Bone loss from any cause (calcium related, inactivity related, age related) makes OI bones even more fragile. In 1997, the National Academy of Sciences developed the following Recommended Dietary Intake for calcium:
Young children (1-3) 500 mg a day
Older children (4-8) 800 mg a day
Preteens/adolescents (9-18) 1,300 mg a day
Men and women (19-50) 1,000 mg a day
Men and women (50+) 1,200 mg a day
These guidelines were developed for people of average height and weight. A person with OI may have lower calcium needs. It is recommended that people with OI, particularly if they are much smaller than average, or have a family history of kidney stones talk to a physician and/or registered dietitian about their individual calcium needs. A measurement of calcium in a 24-hour urine collection may help determine if a person with OI is getting too much or too little calcium.
If you are unable to get the appropriate amount of calcium for your body size and age through your diet, a calcium supplement may be needed. Calcium supplements are also sometimes recommended for people taking certain medications such as bisphosphonates. Check with your doctor to determine if a supplement is necessary.
Low-fat and skim milk have the same amount of calcium as whole milk, but significantly fewer calories. In addition to dairy products, calcium is also found in foods such as broccoli, kale, some dried beans and nuts and soy-based products. Manufacturers are increasingly fortifying other foods, such as cereal and bread, with calcium. Most brands of calcium fortified orange juice have the same amount of calcium as milk.
Vitamin D and Bone Health
Vitamin D is necessary to help the body absorb calcium and make bone. New research suggests that it may play a role in the immune system, and that low levels may contribute to chronic pain. Most of the vitamin D in our bodies is made from sunlight absorbed through the skin. Vitamin D is also found in many fortified foods and in dietary supplements in the form called D-3. A blood test that measures 25(OH)D is the only way to tell if a person has adequate levels of Vitamin D in their system. Researchers recently began recommending that blood levels of vitamin D for children and adults on this test should be increased from a previous recommended level of 20 ng/ml to between 32 and 70 ng/ml. Studies suggest that many people have low vitamin D levels, especially in the winter.
The amount of vitamin D in food or supplements is measured in terms of International Units (IU).The latest research supports the following guidelines for vitamin D for people with OI. See Note: Vitamin D Research in the Resources section for more information.
Suggested Vitamin D-3 Intake for People with OI:
Weight IU per day
50 lbs. (20 kg) 600-800
90 lbs. (40 kg) 1100-1600
110 lbs. (50 kg) 1200-2000
150 lbs (70 kg) and above 2000-2800
Other Nutrients
Vitamin C has many functions in the body, including the production of healthy connective tissues, and the healing of wounds and fractures. Vitamin C is abundant in many fruits (such as citrus fruits, strawberries, and cantaloupe) and vegetables (including tomato, bell peppers, and sweet potato). It is fairly easy to get adequate Vitamin C through the diet. There is some evidence that Vitamin C tablets can increase the risk of kidney stones in people who already have high levels of calcium in the urine. Because high urine calcium affects some people with OI, check with a physician before taking Vitamin C supplements.
Guidelines for a Healthy Diet
The U.S. Department of Agriculture has developed a Food Guide Pyramid to help people make healthy daily food choices (http://www.mypyramid.gov/). The pyramid offers guidelines for the daily number of servings for each of six food groups:
Bread, cereal, rice and pasta
Vegetables
Fruit
Milk, yogurt and cheese
Meat, poultry, fish, dry beans, eggs and nuts
Fats, oils and sweets.
Beverage recommendations stress the need for water every day. Fruit juices should make up only one of the fruit servings per day. Sodas (carbonated beverages) should be limited because they replace milk or water and are usually high in sugar and salt. The phosphorus in sodas also decreases calcium absorption.
It is important to remember that this pyramid was developed for people of average body size and activity level. Children and adults with OI can get guidance from their physician or a dietitian regarding the appropriate number of daily servings for their body size and activity level.
(Malay) Osteogenesis imperfecta (OI dan kadang-kadang dikenali sebagai penyakit tulang rapuh, atau "Lobstein syndrome"[1]) adalah gangguan tulang genetik. Mereka dengan keadaan OI dilahirkan dengan tisu penghubung cacat, atau tanpa keupayaan untuk membinanya, biasanya kerana kekurangan kolagen Jenis I. kekurangan ini timbul akibat penggantian asid amino glycine pada asid amino lebih besar dalam struktur kolagen tiga helik. Rantaian sisi asid amino yang lebih mewujudkan halangan sterik yang membentuk bonjol di binaan kolagen, yang seterusnya mempengaruhi kedua-dua molekul nanomekanikal serta tindak balas antara molekul, yang kedua-dua terjejas. Akibatnya, badan boleh bertindak balas dengan hidrolising struktur kolagen yang tidak sempurna. Jika badan tidak memusnahkan kolagen yang tidak sempurna, hubungan antara gentian halus kolagen dan kristal hidroksiapatit untuk membentuk tulang berubah, menyebabkan kerapuhan. Satu lagi mekanisme penyakit yang dicadangkan ialah bahawa keadaan tegasan di gentian halus kolagen berubah di lokasi mutasi, di mana daya ricih ("shear forces") tempatan yang lebih besar mendorong kepada kegagalan pesat gentian halus walaupun pada beban yang sederhana sebagai keadaan tekanan homogen yang berlaku dalam gentian halus kolagen sihat. Penyeidikan baru ini mencadangkan bahawa OI perlu difahami sebagai suatu fenomena skala-besaran, yang membabitkan mekanisme di peringkat genetik, nano, mikro dan makro-tisu.
Sebagai gangguan genetik, OI dalam sejarah telah telah dilihat sebagai gangguan autosomal dominanpada kolagen Jenis I. Dalam beberapa tahun yang lalu, bentuk resesif autosom telah dikenal pasti. Kebanyakan mereka dengan OI mewarisinya dari ibu atau bapa tetapi dalam 35% kes-kes itu merupakan seorang individu dengan mutasi
(English) Osteogenesis imperfecta (OI and sometimes known as brittle bone disease, or "Lobstein syndrome" is a congenital bone disorder. People with OI are born with defective connective tissue, or without the ability to make it, usually because of a deficiency of Type-I collagen.[2] This deficiency arises from an amino acid substitution of glycine to bulkier amino acids in the collagen triple helix structure. The larger amino acid side-chains create steric hindrance that creates a bulge in the collagen complex, which in turn influences both the molecular nanomechanics as well as the interaction between molecules, which are both compromised.[3] As a result, the body may respond by hydrolyzing the improper collagen structure. If the body does not destroy the improper collagen, the relationship between the collagen fibrils and hydroxyapatite crystals to form bone is altered, causing brittleness.[4] Another suggested disease mechanism is that the stress state within collagen fibrils is altered at the locations of mutations, where locally larger shear forces lead to rapid failure of fibrils even at moderate loads as the homogeneous stress state found in healthy collagen fibrils is lost.[3] These recent works suggest that OI must be understood as a multi-scale phenomenon, which involves mechanisms at the genetic, nano-, micro- and macro-level of tissues.
As a genetic disorder, OI has historically been viewed as an autosomal dominant disorder of type I collagen. In the past several years, there has been the identification of autosomal recessive forms.[citation needed] Most people with OI receive it from a parent but in 35% of cases it is an individual (de novo or "sporadic") mutation.
1. Rawatan (Medication)
Although there is no cure for osteoporosis, the following medications are approved by the FDA for postmenopausal women to prevent and/or treat osteoporosis:
Bisphosphonates: Alendronate (brand name Fosamax®) and Risedronate (brand name Actonel®)
Calcitonin (brand name Miacalcin®)
Estrogen/Hormone Therapy:
Estrogens (brand names, such as Climara® Estrace®, Estraderm®, Estratab®, Ogen®, Ortho-Est®, Premarin®, Vivelle®, and others)
Estrogens and Progestins (brand names, such as Activella™, FemHrt®, Premphase®, Prempro®, and others)
Parathyroid Hormone: Teriparatide (PTH (1-34), brand name Fortéo®)
Selective Estrogen Receptor Modulators (SERMs): Raloxifene (brand name Evista®)
Alendronate is approved as a treatment for osteoporosis in men and is approved for treatment of glucocorticoid (steroid)-induced osteoporosis in men and women. Risedronate is approved for prevention and treatment of glucocorticoid-induced osteoporosis in men and women.
Parathyroid hormone is approved for treatment of osteoporosis in men who are at high risk of fracture.
Treatments under investigation include sodium fluoride, vitamin D metabolites, and other bisphosphonates and selective estrogen receptor modulators.
References:
The NIH Osteoporosis and Related Bone Diseases ~ National Resource Center
2. Herbals atau Nutritional and Herbal Therapy for Osteoporosis
Calcium (1,000 mg a day, but should be increased for osteoporosis) is extremely important. If your blood levels are low in this mineral, calcium will be taken from your bones in order give the muscles and nerves the amount they need.
Vitamin D is needed in order to absorb calcium.
Magnesium (500 mg a day) helps convert Vitamin D into its usable form.
Vitamin K is essential for bone mineralization. Low levels are associated with low bone density.
Isoflavone has a positve effect on bone metabolism.
Vitamins B12 and B6, folic acid keep homecysteine levels down, which has been linked to osteoporosis risk
Dura-Bone is an excellent supplement to strengthen bones and tendons and help stave off osteoporosis.
3. Diet
Calcium and Bone Health
Calcium does not improve the basic collagen defects that cause OI. Even so, people with OI need to get adequate calcium in their diets to develop peak bone mass and prevent bone loss. Bone loss from any cause (calcium related, inactivity related, age related) makes OI bones even more fragile. In 1997, the National Academy of Sciences developed the following Recommended Dietary Intake for calcium:
Young children (1-3) 500 mg a day
Older children (4-8) 800 mg a day
Preteens/adolescents (9-18) 1,300 mg a day
Men and women (19-50) 1,000 mg a day
Men and women (50+) 1,200 mg a day
These guidelines were developed for people of average height and weight. A person with OI may have lower calcium needs. It is recommended that people with OI, particularly if they are much smaller than average, or have a family history of kidney stones talk to a physician and/or registered dietitian about their individual calcium needs. A measurement of calcium in a 24-hour urine collection may help determine if a person with OI is getting too much or too little calcium.
If you are unable to get the appropriate amount of calcium for your body size and age through your diet, a calcium supplement may be needed. Calcium supplements are also sometimes recommended for people taking certain medications such as bisphosphonates. Check with your doctor to determine if a supplement is necessary.
Low-fat and skim milk have the same amount of calcium as whole milk, but significantly fewer calories. In addition to dairy products, calcium is also found in foods such as broccoli, kale, some dried beans and nuts and soy-based products. Manufacturers are increasingly fortifying other foods, such as cereal and bread, with calcium. Most brands of calcium fortified orange juice have the same amount of calcium as milk.
Vitamin D and Bone Health
Vitamin D is necessary to help the body absorb calcium and make bone. New research suggests that it may play a role in the immune system, and that low levels may contribute to chronic pain. Most of the vitamin D in our bodies is made from sunlight absorbed through the skin. Vitamin D is also found in many fortified foods and in dietary supplements in the form called D-3. A blood test that measures 25(OH)D is the only way to tell if a person has adequate levels of Vitamin D in their system. Researchers recently began recommending that blood levels of vitamin D for children and adults on this test should be increased from a previous recommended level of 20 ng/ml to between 32 and 70 ng/ml. Studies suggest that many people have low vitamin D levels, especially in the winter.
The amount of vitamin D in food or supplements is measured in terms of International Units (IU).The latest research supports the following guidelines for vitamin D for people with OI. See Note: Vitamin D Research in the Resources section for more information.
Suggested Vitamin D-3 Intake for People with OI:
Weight IU per day
50 lbs. (20 kg) 600-800
90 lbs. (40 kg) 1100-1600
110 lbs. (50 kg) 1200-2000
150 lbs (70 kg) and above 2000-2800
Other Nutrients
Vitamin C has many functions in the body, including the production of healthy connective tissues, and the healing of wounds and fractures. Vitamin C is abundant in many fruits (such as citrus fruits, strawberries, and cantaloupe) and vegetables (including tomato, bell peppers, and sweet potato). It is fairly easy to get adequate Vitamin C through the diet. There is some evidence that Vitamin C tablets can increase the risk of kidney stones in people who already have high levels of calcium in the urine. Because high urine calcium affects some people with OI, check with a physician before taking Vitamin C supplements.
Guidelines for a Healthy Diet
The U.S. Department of Agriculture has developed a Food Guide Pyramid to help people make healthy daily food choices (http://www.mypyramid.gov/). The pyramid offers guidelines for the daily number of servings for each of six food groups:
Bread, cereal, rice and pasta
Vegetables
Fruit
Milk, yogurt and cheese
Meat, poultry, fish, dry beans, eggs and nuts
Fats, oils and sweets.
Beverage recommendations stress the need for water every day. Fruit juices should make up only one of the fruit servings per day. Sodas (carbonated beverages) should be limited because they replace milk or water and are usually high in sugar and salt. The phosphorus in sodas also decreases calcium absorption.
It is important to remember that this pyramid was developed for people of average body size and activity level. Children and adults with OI can get guidance from their physician or a dietitian regarding the appropriate number of daily servings for their body size and activity level.
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