Vanilmandelate is a metabolite of epinephrine and norepinephrine (also known as adrenaline and noradrenaline).

Semen volume refers to the amount of seminal fluid ejaculated during a male's orgasm. On average, the volume of semen in a single ejaculation typically ranges between 2 to 5 milliliters, equivalent to approximately 0.12 to 0.31 cubic inches in volume for human males. However, this volume can vary among individuals and may be influenced by factors such as age, sexual activity, and overall health.

Semen volume is an essential aspect of male reproductive health, as it plays a role in delivering sperm to the female reproductive tract for fertilization. It is commonly analyzed in semen analysis tests to assess male fertility and reproductive function, as deviations from the normal volume may indicate underlying issues. It's important to note that the idea of increasing semen volume through products or methods is largely a myth, as it is primarily determined by individual biology and health factors, not external interventions.

Drinking more fluids can help lower your risk of kidney stones. The goal is to increase the amount of urine that flows through your kidneys and also to lower the concentrations of substances that promote stone formation. While you can vary the types of beverages you drink, sugar-sweetened beverages (such as soda and sports drinks) actually seem to increase the risk of kidney stones; they have other negative health effects as well and should therefore be avoided.

Vomitoxin (aka Deoxynivalenol or DON), a tricothecene mycotoxin, is produced by several species of Fusarium. DON has been associated with outbreaks of acute gastrointestinal illness in humans. The FDA advisory level for DON for human consumption is 1 ppm.

Vomitoxin (aka Deoxynivalenol or DON), a tricothecene mycotoxin, is produced by several species of Fusarium. DON has been associated with outbreaks of acute gastrointestinal illness in humans. The FDA advisory level for DON for human consumption is 1 ppm.

A von Willebrand factor (vWF) activity – ristocetin cofactor test lets you evaluate the functioning of the protein vWF, which helps blood to clot. A clot is a lump of blood that the body produces to prevent excessive bleeding by sealing leaks from blood vessels caused by wounds, cuts, scratches, or other conditions.

The blood’s ability to clot is a complex process involving platelets (also called thrombocytes) and proteins called clotting factors. Platelets are oval-shaped cells made in the bone marrow. Most clotting factors are made in the liver. Some, like vWF, are made in blood vessel walls.

What Is a Von Willebrand Factor Antigen Test?

Von Willebrand factor is involved in a few stages of blood clotting.

Proteins called clotting factors are needed for blood to clot properly and help prevent too much bleeding. A von Willebrand factor (vWF) antigen test measures the amount of a clotting factor called von Willebrand factor.

The body's clotting factors work together in a special order, almost like pieces of a puzzle. When the last piece is in place, the clot develops. But if there aren't enough of them, or any of them don't work as they should, it can take longer than normal for blood to clot.

Normally, when a blood vessel is damaged and bleeding begins, VWF forms an adhesive bridge between activated cell fragments called platelets and the injury site. This is followed by the clumping (aggregation) of platelets at the site and a series of actions referred to as activation of the coagulation cascade, resulting in the formation of a stable blood clot.

The von Willebrand Factor (VWF) Activity/VWF Antigen Ratio is a critical laboratory marker used in the diagnosis and evaluation of von Willebrand disease (VWD), a bleeding disorder caused by a deficiency or dysfunction of von Willebrand factor, a protein essential for blood clotting. This ratio is particularly helpful in distinguishing between different types of VWD and in assessing the severity of the condition.

VWF GPIbM Activity

(Von Willebrand Factor Glycoprotein Ib-Mutant Activity)

What Is VWF GPIbM Activity?

VWF GPIbM Activity is a specialized test that measures the functional activity of von Willebrand factor (VWF) — a protein essential for normal blood clotting. This assay assesses how well VWF can bind to platelets, a key step in the formation of a blood clot to stop bleeding.

The test uses a mutant form of platelet receptor GPIbα (glycoprotein Ib alpha) to detect VWF activity, which makes it more stable, sensitive, and specific than older tests like the ristocetin cofactor assay (VWF:RCo).

VWF GPIbM Activity is used primarily in the diagnosis and classification of von Willebrand disease (VWD), the most common inherited bleeding disorder.

The von Willebrand Factor: Collagen Binding (vWF:CB) assay is a sophisticated laboratory test that plays a crucial role in evaluating the functional capacity of von Willebrand factor (vWF), a multimeric glycoprotein essential for primary hemostasis. This test specifically assesses vWF's ability to bind to collagen, a critical step in the initial phase of blood clot formation.

The VZV IgG ELISA detects long-lasting antibodies to varicella-zoster and is reported as Positive/Negative (sometimes Equivocal or an index). Positive usually means immunity from past infection or vaccination, but it doesn’t diagnose an active rash or date exposure. Negative suggests no documented immunity or testing too early after vaccination/exposure; antibodies often appear within 2–3 weeks, so retest in 2–6 weeks if timing is close. Suspected chickenpox or shingles should be confirmed with PCR from lesions, not IgG. Consider immune-status documentation for pregnancy, immunosuppression, and occupational settings. IgM isn’t recommended due to false positives. Always use your lab’s reference ranges for final interpretation.