Histidine is a semi-essential amino acid which is formed in the breakdown of carnosine. Red meat is a common source of carnosine, and therefore histadine. Other food sources include poultry, fish, nuts, seeds, and grains. Histidine and histamine have a unique relationship. The amino acid histadine becomes histamine via a vitamin B6- dependent enzyme called histidine decarboxylase. 

Histidine is a semi-essential amino acid which is formed in the breakdown of carnosine. Red meat is a common source of carnosine, and therefore histadine. Other food sources include poultry, fish, nuts, seeds, and grains. Histidine and histamine have a unique relationship. The amino acid histadine becomes histamine via a vitamin B6- dependent enzyme called histidine decarboxylase. 

Histidine ameliorates fatigue, promotes clear thinking and concentration, reduces appetite, decreases anxiety, improves sleep and glucose homeostasis, and gives rise to histamine.

Histidine is a semi-essential amino acid which is formed in the breakdown of carnosine. Red meat is a common source of carnosine, and therefore histadine. 

Other food sources include poultry, fish, nuts, seeds, and grains. Histidine and histamine have a unique relationship. The amino acid histadine becomes histamine via a vitamin B6- dependent enzyme called histidine decarboxylase. 

With this, decreased amounts of histidine and insufficient vitamin B6 can subsequently lead to a decrease in histamine concentration. This may impair digestion, since histamine binds to H2 receptors located on the surface of parietal cells to stimulate gastric acid secretion, necessary for protein breakdown.

Histidine also inhibits the production of proinflammatory cytokines by monocytes and is therefore anti-inflammatory and antioxidant. 

With these beneficial effects, histidine supplementation has been shown to improve insulin resistance, reduce BMI, suppress inflammation, and lower oxidative stress in obese women with metabolic syndrome. 

Interestingly, histadine can also be broken down to form urocanic acid in the liver and skin. Urocanic acid absorbs UV light and is thought to act as a natural sunscreen.

Histidine is a semi-essential amino acid which is formed in the breakdown of carnosine. Red meat is a common source of carnosine, and therefore histadine. Other food sources include poultry, fish, nuts, seeds, and grains. Histidine and histamine have a unique relationship. The amino acid histadine becomes histamine via a vitamin B6- dependent enzyme called histidine decarboxylase. 

Histidine is involved in one-carbon units for conversion of formiminoglutamic acid (FIGLU) to glutamic acid.

- High plasma histidine has been associated with increased plasma glutamic acid, alanine and glutamine, and decreased branched-chain amino acids.

- Elevated urine histidine means it is not available for hemoglobin production. Hemoglobin is 10% histidine.

- High levels have been associated with progression of type 2 diabetes after gestational diabetes (= a type of diabetes that can develop during pregnancy in women who don't already have diabetes.)

- Decreased plasma histidine was associated with increased risk of ulcerative colitis relapse; a higher serum CRP in Crohn’s disease; chronic kidney disease; increased inflammation; and atopic dermatitis.

Histidine is the amino acid most necessary during stress. Amino acids are the building blocks of protein in our bodies.

Histidine is the amino acid most necessary during stress. Amino acids are the building blocks of protein in our bodies.

Histidine ameliorates fatigue, promotes clear thinking and concentration, reduces appetite, decreases anxiety, improves sleep and glucose homeostasis, and gives rise to histamine.

This test distinguishes drug-induced lupus from other lupus variants and autoimmune conditions. Though not a definitive diagnostic tool, histone antibodies align with drug-induced lupus. It's often ordered alongside a positive ANA test and sometimes an anti-dsDNA test. Following drug-induced lupus diagnosis, discontinuing the drug is advised, with histone antibody tests for monitoring. These tests are ordered when an individual taking medication for weeks to years exhibits symptoms linked to drug-induced lupus, especially without prior autoimmune history. Symptoms include joint pain, fatigue, fever, myalgia, malar rash, sunlight sensitivity, and weight loss. CNS and kidney symptoms are rarer in drug-induced lupus compared to systemic lupus erythematosus (SLE). Post-drug discontinuation, the histone antibody test can track changes. A negative result suggests alternatives, yet drug-induced lupus is possible without histone antibodies.

Histoplasma complement fixation is a blood test that checks for infection from a fungus called Histoplasma capsulatum (H capsulatum), which causes the disease histoplasmosis.

AIDS is caused by 2 known types of HIV. HIV type 1 (HIV-1) is found in patients with AIDS or AIDS-related complex and in asymptomatic infected individuals at high risk for AIDS. The virus is transmitted by sexual contact, by exposure to infected blood or blood products, or from an infected mother to her fetus or infant. HIV type 2 (HIV-2) infection is endemic only in West Africa, and it has been identified in individuals who had sexual relations with individuals from that geographic region. HIV-2 is similar to HIV-1 in viral morphology, overall genomic structure, and its ability to cause AIDS.

AIDS is caused by 2 known types of HIV. HIV type 1 (HIV-1) is found in patients with AIDS or AIDS-related complex and in asymptomatic infected individuals at high risk for AIDS. The virus is transmitted by sexual contact, by exposure to infected blood or blood products, or from an infected mother to her fetus or infant. HIV type 2 (HIV-2) infection is endemic only in West Africa, and it has been identified in individuals who had sexual relations with individuals from that geographic region. HIV-2 is similar to HIV-1 in viral morphology, overall genomic structure, and its ability to cause AIDS.

Human Immunodeficiency Virus (HIV) is categorized into two distinct types: HIV-1 and HIV-2. Both are retroviruses that attack the body's immune system, but they have differences in their geographical prevalence, transmission rates, and progression to Acquired Immunodeficiency Syndrome (AIDS).

HIV-1: This is the most common type of HIV and is found worldwide. It's responsible for the vast majority of HIV infections globally. HIV-1 is characterized by its rapid transmission and progression. It is more aggressive and infects cells faster than HIV-2, leading to a quicker decline in immune function if left untreated. HIV-1 is divided into four groups: M (Main), O (Outlier), N (Non-M, Non-O), and P, with Group M responsible for the majority of infections worldwide. Further, Group M is divided into multiple subtypes and circulating recombinant forms (CRFs).

HIV-2: This type is less common and is predominantly found in West Africa, with some cases in India and Europe. Compared to HIV-1, HIV-2 is transmitted less efficiently, particularly from mother to child and through heterosexual contact. The progression of HIV-2 to AIDS is generally slower, and it may have a longer asymptomatic stage. HIV-2 is also less responsive to certain antiretroviral therapies, requiring specific treatment regimens.

AIDS is caused by 2 known types of HIV. HIV type 1 (HIV-1) is found in patients with AIDS or AIDS-related complex and in asymptomatic infected individuals at high risk for AIDS. The virus is transmitted by sexual contact, by exposure to infected blood or blood products, or from an infected mother to her fetus or infant. HIV type 2 (HIV-2) infection is endemic only in West Africa, and it has been identified in individuals who had sexual relations with individuals from that geographic region. HIV-2 is similar to HIV-1 in viral morphology, overall genomic structure, and its ability to cause AIDS.

AIDS is caused by 2 known types of HIV. HIV type 1 (HIV-1) is found in patients with AIDS or AIDS-related complex and in asymptomatic infected individuals at high risk for AIDS. The virus is transmitted by sexual contact, by exposure to infected blood or blood products, or from an infected mother to her fetus or infant. HIV type 2 (HIV-2) infection is endemic only in West Africa, and it has been identified in individuals who had sexual relations with individuals from that geographic region. HIV-2 is similar to HIV-1 in viral morphology, overall genomic structure, and its ability to cause AIDS.

HIV Ab/p24 Ag with Reflex is a diagnostic test used for the detection of HIV infection. It combines the identification of antibodies (Ab) and p24 antigens (Ag) associated with the HIV virus. The test is usually performed as an initial screening tool, utilizing a sensitive combination assay to detect both the presence of antibodies produced by the body in response to HIV and the p24 antigen, which is an early marker of HIV infection.

The fourth generation tests can identify both HIV-specific antigen p24 and HIV antibodies with a blood sample.

The fourth generation HIV test, also called an enzyme-linked immunosorbent assay (ELISA) test, is a more complete screening that can identify acute HIV. This is the time when the virus is multiplying rapidly and you’re more likely to pass the infection.

In the first few weeks after exposure to HIV, your body produces an antigen known as p24. This protein is only present in people who have acute HIV infection. It triggers your immune system to respond.

The fourth generation tests require a blood sample that’s sent to a lab for testing. Blood testing done by a lab is the most accurate type of test.

This test looks for HIV infection in your blood or saliva.

HIV is the virus that causes AIDS. About 1 in 5 people who are infected with HIV don't know it because they may not have symptoms. HIV comes in 2 forms:

• HIV-1. This type is found worldwide.

• HIV-2. This type is mainly found in western Africa. But it has spread to the U.S.

This test is one of several tests that look for HIV infection. Some tests take a few days for results to come back. Rapid HIV tests can give your results in about 20 minutes. Getting an early diagnosis of HIV is important because you can start treatment early and also take steps to keep from spreading the virus to others.

- To determine whether you have human leukocyte antigen B27 (HLA-B27) on the surface of your cells

- To help assess the likelihood that you have an autoimmune disorder associated with the presence of HLA-B27.

- Autoimmune disorders occur when the immune system mistakenly targets the body’s own cells and tissues.

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The HLA-B27 test is primarily ordered to help strengthen or confirm a suspected diagnosis of ankylosing spondylitis (AS), reactive arthritis, juvenile rheumatoid arthritis (JRA), or sometimes anterior uveitis. The HLA-B27 test is not diagnostic; that is, it is not a definitive test that can be used to diagnose or rule out a disorder. The result adds information and is one piece of evidence used along with the evaluation of signs, symptoms, and other laboratory tests to support or rule out the diagnosis of certain autoimmune disorders, such as ankylosing spondylitis and reactive arthritis.

The HLA-B27 test may be ordered as part of a group of tests used to help diagnose and evaluate conditions causing arthritis-like chronic joint pain, stiffness, and inflammation. This group of tests may include a rheumatoid factor (RF) with either an erythrocyte sedimentation rate (ESR) or a C-reactive protein (CRP). HLA-B27 is sometimes ordered to help evaluate someone with recurrent uveitis that is not caused by a recognizable disease process.