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Rabu, 07 Januari 2009

Thrombocytopenia (reduced platelet count)

Thrombocytopenia (reduced platelet count)

Written by Dr Claire Harrison, Consultant Haematologist, St Thomas' Hospital, London and Professor Samuel Machin, Department of Haematology, University College London Hospital

What is thrombocytopenia?Thrombocytopenia is the term for a reduced platelet (thrombocyte) count. It happens when platelets are lost from the circulation faster than they can be replaced from the bone marrow where they are made.

Did you know?
All blood cells are created within the bone marrow.

Thrombocytopenia can result from:
a failure of platelet production
an increased rate of removal from blood.What are platelets?Platelets are tiny cells that circulate in the blood and whose function is to take part in the clotting process.Inside each platelet are many granules, containing compounds that enhance the ability of platelets to stick to each other and also to the surface of a damaged blood vessel wall.

Figure 1: Normal blood film
The platelet count in the circulating blood is normally between 150 and 400 million per millilitre of blood. Newborn babies have a slightly lower level, but are normally within the adult range by three months of age.Many factors can influence an individual's platelet count including exercise and racial origin. The average life span of a platelet in the blood is 10 days.What do platelets do?Platelets are essential in the formation of blood clots to prevent haemorrhage - bleeding from a ruptured blood vessel.An adequate number of normally functioning platelets is also needed to prevent leakage of red blood cells from apparently uninjured vessels.In the event of bleeding, muscles in the vessel wall contract and reduce blood flow. The platelets then stick to each other (aggregation) and hold on to the vessel wall (primary haemostasis). The coagulation factors are then activated, resulting in normally liquid blood becoming an insoluble clot or glue.What are the risks of a low platelet count? The main effect of a reduced platelet count is an increased risk of bleeding, but this rarely occurs until there are less than 80-100 million platelets per ml.There is not a close relationship between the number of platelets and the severity of bleeding, but there is an increasing risk of haemorrhage if platelet numbers fall or if platelet function is impaired (for example by aspirin, which reduces the 'stickiness' of the platelets).There is a particularly high risk of spontaneous bleeding once the platelet count drops below 10 million per ml. The bleeding is usually seen on the skin in the form of tiny pin-prick haemorrhages (purpura), or bruises (ecchymoses) following minor trauma.Bleeding from the nose and the gums is also quite common. More serious haemorrhage can occur at the back of the eye (retina), sometimes threatening sight.The most serious complication, which is potentially fatal, is spontaneous bleeding inside the head (intracranial) or from the lining of the gut (gastrointestinal).Types of thrombocytopeniaSpecific types of low platelet count include:
idiopathic thrombocytopenic purpura (ITP)
thrombotic thrombocytopenic purpura (TTP)
haemolytic uraemic syndrome. What causes a low platelet count?The many different causes of thrombocytopenia are detailed below. These causes are not mutually exclusive and more than one may be responsible for an abnormal platelet count.

Causes summary
False thrombocytopenia
Clot in the sample.
Platelets clumped.
Congenital thrombocytopenia
Rare inherited disorders (eg May Hegglin anomaly, Bernard Soulier syndrome).
Defective platelet production
Bone marrow aplasia (failure).
Metabolic disorders, eg kidney failure, alcohol.
Abnormal platelet precursors: viral infections, inherited abnormalities.
Bone marrow infiltration, eg leukaemia, lymphoma.
Diminished platelet survival
Antibodies in response to drugs, blood transfusion or another disease, eg glandular fever, malaria.
Unknown cause (ITP).
Clotting disorder (DIC).
Blood disorder (TTP).
Loss of platelets from the circulation
Massive blood transfusion or exchange.
Enlarged spleen.

Artefactual (false) thrombocytopenia Some people have platelets that stick together due to the presence of proteins in the blood (antibodies) that bind to the platelets.These antibodies also bind to a chemical in blood that is tested in the lab, giving a falsely low platelet count. For this reason, it is helpful to repeat the sample in different tubes with different chemicals.The platelet count can also be reduced if the blood sample is difficult to take and the blood clots - thus using up some of the platelets.

Congenital thrombocytopeniaSeveral rare inherited diseases cause low platelet counts. The severity of the thrombocytopenia varies with the condition and also the individual patient.In some of these conditions, eg May Hegglin anomaly, bleeding doesn't happen often.In other inherited diseases, eg Bernard Soulier syndrome, the platelets function less well and lifelong bleeding symptoms can occur.

Defective platelet production Platelets are produced within the bone marrow from cells called megakaryocytes.If there is a problem in the bone marrow, for example due to abnormal cells, then the number of megakaryocytes will drop, lowering the number of platelets that can be produced.Examples of abnormal cells accumulating in the bone marrow include:
acute leukaemia where leukaemic cells, or 'blasts', are seen
other abnormal cancer cells such as lymphoma
more rarely, when cancers develop in another part of the body and have spread (metastasised) to the bone marrow.Alternatively, there may be something wrong with the platelet production process itself so not enough platelets are formed.Impaired platelet production can also be due to:
the side-effects of drugs such as chemotherapy (anti-cancer) agents
viral infections such as HIV
metabolic disorders such as shortage of vitamin B12 or folic acid, kidney failure, alcohol.
an abnormality of the bone marrow called myelodysplasia.Sometimes platelet production is defective because of an abnormality in the cells that make up the structural parts of the bone marrow, called the stroma. Examples include:
marble bone disease (osteopetrosis). This hereditary condition causes dense, brittle bones at the expense of bone marrow.

myelofibrosis. This causes a massive increase in the amount of fibrous tissue, which impairs platelet production as well as the production of other blood cells.
Diminished platelet survivalPlatelet numbers fall if they are removed from the circulation more rapidly than they are produced.Platelets are removed for several reasons. They may be coated with an antibody, or are clumped together and then removed.Antibodies that cause platelet removal can be due to:
infections such as HIV
medicines such as the anti-malaria drug quinine
a specific disease in which abnormal production of other antibodies may occur, eg rheumatoid arthritis, the skin disease systemic lupus erythematosis or the blood disease chronic lymphocytic leukaemia.These antibodies can also occur in someone who is otherwise completely well. This is called idiopathic thrombocytopinea (ITP) - literally, a low platelet count of unknown cause.Alternatively, the platelets may be used up if the blood clotting process is inappropriately 'switched on'. This condition is known as disseminated intravascular coagulation (DIC).DIC can result from the following:
in severe infections such as meningitis.
as a complication of pregnancy or labour, eg high blood pressure and pre-eclampsia
in some cancers, specifically types of acute myeloid leukaemia and prostate cancer
in some rare blood disorders such as thrombotic thrombocytopenic purpura or haemolytic uraemic syndrome (sometimes due to food poisoning outbreaks).
Loss of platelets from the circulation
Abnormal distribution of platelets: a low platelet count may be due to a build up of platelets outside the normal blood pool, for example in a patient with a very large spleen.
Dilution of platelets: the platelet count can fall when a patient is transfused with a large volume of red blood cells that do not contain platelets, because of dilution of normal blood factors.How is a low platelet count diagnosed?Investigation usually starts with a history of symptoms, signs of bleeding or bruising, other medical problems, recent infections and medications. A blood test is then taken.In the haematology lab the doctor:
performs a full blood count
examines the blood film under a microscope (see Figure 1)
examines the blood sample in the test tube.Usually, another full blood count sample is requested to confirm the result and see if it is a persisting abnormality.Depending upon the severity of the platelet lack and the likely cause, the person is likely to be referred to a haematologist at the hospital.If the platelet count is very low, the person may need to be seen on the same day, and have a bone marrow test performed.A bone marrow test is done under local anaesthetic, with samples usually taken from the back of the pelvis. This test helps the haematologist to decide if platelets are being produced normally and whether the rest of the bone marrow appears normal.Further tests such as genetic tests can also be done on a bone marrow sample.What treatment is available? The choice of treatment depends upon the severity of the platelet count, its cause and whether or not there is any bleeding.
In a type of thrombocytopenia called TTP, the use of platelet concentrates is hazardous.
If life-threatening bleeding occurs, eg to the head or bowel, urgent treatment is needed with platelet concentrates via blood transfusion.The effect of the concentrates is then monitored by measuring the platelet count and assessing any continuing bleeding.The management of acute bleeding also involves treatment of the underlying cause of the low platelets.If there is no major bleeding, treatment is aimed at the cause of the low platelet count.
Figure 2: A bag of platelets for transfusion
If a drug is thought to be the cause, it should be stopped, providing this is safe, and the platelet count monitored.
If an infection is suspected, treatment of it with antibiotics could be started.
For some infections, especially viral ones such as glandular fever, there is no specific treatment and close observation may be necessary.
When an infection results in a low platelet count by causing DIC, treatment tackles the underlying infection and the DIC. Blood components are used to replace the clotting factors and platelets.
If platelet production fails due to the presence of abnormal or malignant cells, treatment is directed at those abnormal cells - for example, chemotherapy or radiotherapy would be used in leukaemia. This can temporarily damage the bone marrow and worsen the thrombocytopenia. Transfusions would then be given if the platelet count becomes very low until it reaches a safer level or the bone marrow recovers.

Israel to attack Palestinian

Please note before, in my opinion it is intended for members of HAMAS, but why even the other Muslim residents also affected?
Moreover, aid from around the world for the Palestinian people even in the block by Israel, is really inhuman perilakku them.
But why the council said the UN is not at all slightly what they fear? This also reflects the state also be Afghanistan.
I feel confused with their attitude.
What are establishment of the United Nations?

Selasa, 06 Januari 2009

Outbreak of Streptococcus pneumoniae serotype 1 pneumonia in a United Kingdom school

Atul Gupta, specialist registrar, paediatric respiratory medicine1, F-M Khaw, consultant in health protection2, E L Stokle, senior health protection nurse2, R C George, consultant medical microbiologist3, R Pebody, consultant3, R E Stansfield, consultant microbiologist4, C L Sheppard, advanced healthcare scientist3, M Slack, consultant medical microbiologist3, R Gorton, consultant regional epidemiologist2, D A Spencer, consultant paediatric respiratory medicine1

1 Paediatric Respiratory Unit, Freeman Hospital, Newcastle upon Tyne NE7 7DN, 2 Health Protection Agency North East, Northern Office, Citygate, Newcastle upon Tyne NE1 4WH, 3 Health Protection Agency, Centre for Infections, London NW9 5EQ, 4 Microbiology Laboratory Service, Northumbria Healthcare NHS Foundation Trust, North Tyneside General Hospital, North Shields NE29 8NH

Correspondence to: F-M Khaw

Healthcare workers and teachers should report suspected outbreaks of serotype 1 pneumococcal disease early, and childhood immunisation should be considered

The first 150 words of the full text of this article appear below.

Pneumococcal pneumonia is not generally regarded as contagious.1 Although epidemics of pneumococcal disease have been reported (in sub-Saharan Africa2 3 and Canada4), outbreaks of pneumococcal infection are uncommon and are generally restricted to high risk individuals such as alcoholics,5 residents in shelters for the homeless,6 and people living in close groups7 including military camps,8 prisons,9 day care centres,10 and nursing homes.11 Recent reports have indicated that serotype 1 pneumococcus is largely responsible for the exponential increase in the incidence of empyema and complicated pneumonia seen in children in several countries over the past decade.12 13 14 There is also evidence of outbreaks of other forms of invasive serotype 1 disease in many countries.2 15 16 In contrast to most other invasive serotypes, carriage of serotype 1 is rarely detected in the nasopharynx of either adults or children, suggesting short duration of carriage or high virulence.17 18

There have been no reports of outbreaks of pneumococcal . . . [Full text of this article]

Published 31 December 2008, doi:10.1136/bmj.a2964
Cite this as: BMJ 2008;337:a2964

Behind Soft ice cream

Literature ice cream will be Visible to the softness and yummy Taste. To make and store ice cream so yummy Taste and tenderness he Maintained, is the key Chemical. Without a solution koligatif nature or attributes may not colloidal delicious ice cream can be produced. 
The structure and content of ice cream 
Ice cream is not another form of yeast (dispersi gas in liquid) that preserved by cooling. Although the ice cream appears to exist as a solid, if viewed with the microscope will appear to be any of the four components, namely pad at globula fat milk, water (the size is not larger than 0.1 mm), Crystal-small ice crystals , And the water dissolves yes, salt, milk and protein. 
Various standards of food products in the world allow inflate the ice cream mixture with water to be twice the volume (called the maximum 100 percent overrun). Ice cream with the content of the water will feel more and more liquid, warmer, so do not feel eaten. 
When the fat content of milk is too low, the ice will make great and the coarser texture and feel cold. Emulsifier and stabilizer can cover the attributes that caused the lack of bad fat milk and can Taste sticky. 
Equipment Manufacturer of ice cream 
Nancy Johnson of Philadelphia is the first tool to create ice cream. Tools that it is created from wood bucket in which there is a smaller Vessel from the metal. Metal container can be Played using a pedal. In the space between the container and a small Wooden bucket filled with a mixture of ice and salt. Tools of the modern time, it still uses the same Principles . 
Making ice cream is actually just a simple, namely, the compound materials, and then cold. Pure water pressure in the atmosphere will coagulate 1 on the temperature 00 C. However, when the Substances are dissolved in water, the freezing point of water will Decrease. So, to Freeze the dough ice cream also requires temperatures below 00 C. For the dough ice cream included in the metal container, and then in the space between the Wooden Buckets and inserted a metal container of ice. 
Initially, the ice temperature will be less than 00 C (try to check this by measuring the temperature of the ice out of the Refrigerator). However, the surfaces of ice directly contact with the water temperatures will soon reach Rise 00 C, and some will melt. Temperature of the mixture of ice and water will be fixed overnight 00 C for not all ice melt. As mentioned above, clearly a mixture of ice cream does not coagulate in the temperature of 00 C koligatif nature of the Decline due to the freezing point. 

When you spreads a little salt to the mixture of ice and water before, we get a different matter. Discharge of ice water with salt dissolves Immediately will be that we add. Thus, the ice crystals will be floating in the Saline solution. Because the salt solution will have a freezing point lower than 00 C, ice will drop temperatures to the freezing point is reached salt water. In other words, a mixture of ice cream was surrounded by a Saline solution that the temperature lower than 00 C dough ice cream so that it will be frostbitten. 
But, whoa! If the mixture is only left alone will not Freeze ice cream produced, but dense cloud of meetings and contains a Crystal-Crystal of ice that will not be good if eaten. When you want good ice cream in the mouth, during the freezing process was used, the dough must be unstable. Stirring the mixture or shuffle during the freezing process is key in making the ice cream is good. 

The process aims to double this unstable. First, to understate the size of ice crystals that formed; the small size of the Crystal ice, the soft ice cream is formed. Second, the process will occur mixing water into the dough ice cream. Bubbles, bubbles of water mixed into the dough is yeast produce a uniform (homogeneous). 
Role emulsifier 
Stirring and simple method of cooling the same time this was a cause other problems. Basic Cream Transfer of a small globula fat suspension in the water. Globula-globula not join each other because each is surrounded by a membrane protein attract water, the water and make each globula keep stray. Stirring will damage the membrane proteins that make globula fat then can draw on each other. As a result, the cream will Rise to the surface. This is intended to be made when the Butter or oil, but clearly does not want to be made when the ice cream. 
Resolution simplest is to add emulsifier in the mixture. Molecular emulsifier will replace the membrane protein, one molecule end will drag in the water, while one end will solve the fat. Lecitin, a molecule found in the yellow eggs, emulsifier is a simple example. Therefore, one of the materials to make ice cream is yellow. In addition, it can be used in mono-or-gliserida or polisorbat that can dispersi globula fat more effectively. 
Can be made in the shell Vessel 
Because of the Principles of making it a very simple, so there is never funny Incident in the making of ice cream. The United States Air Force pilots during World War II (at the time of the Battlefield of hard to get ice cream) to make creative use of ice cream container with Cannon! The flight is to observe and get a gun that appeared to have the container temperature and vibration absorption spectrophotometer that are suitable to produce ice cream. So, every time they go Attack of the opponent, not forget they put a big container containing the dough ice cream. The result in the return trip from the Attack they will be able to enjoy a tasty ice cream. 

Storage of ice cream 
When ice cream is not Stored properly, some ice cream melt the ice crystals will form a larger, and when added back to the cooling of the ice crystals will GROW Belly. This will lead to a more coarse texture and uncomfortable in the mouth. In addition, the actual texture Rough this can also result because laktosa (milk) and will Crystals solution of the difficult and protracted return. 
To overcome this, when you finish eating (before the store again), can spreads a little looks or cellulose powder in the ice cream. Powder-powder will absorb the strong melt water, so the formation of ice crystals that can be prevented.

Senin, 05 Januari 2009

Facebook and Twitter and friends

People keeps comparing those services.
I don’t get it. They’re completely different. Twitter is an open conversation and a place where you meet new friends. Facebook is a closed conversation and a place where you meet old friends.
I just did a quick count. On twitter I follow 299 people. And 37 of them are friends to the level that I would have said hello if I met them on the street. On Facebook 151 of my 200 friends are at the same level.
That said. Currently I rarely visit Facebook. And I use Twitter all day long.

Web 2.0

Web 2.0 is an application that can provide office applications, video processing, table calculations, and various other applications so that it does not need to install the programs in your PC. 

The definition of social media in the context of Web 2.0 applications is a vessel that can mngerjakan content or activity in the same virtual world, so the application can be combined based on ideas of each individual 
So that the application or program can be resolved correctly, and can benefit all parties 

The difference between the concept of Web 1.0 and Web 2.0 is 
Web 1.0 is the Internet that is 1 in the direction and content of initialization. The provider provides content and media via the Internet and users access and use. 

Web 2.0 is the opposite of web 1.0, then penggunalah that provide more content. The provider only provides media applications such as Internet and the user will fill in the content and is used and accessed by other users.