The TB2-NIL biomarker is a critical component of the QuantiFERON-TB Gold Plus (QFT-Plus) assay, which is used to detect Mycobacterium tuberculosis infection. In this context, 'NIL' refers to the baseline interferon-gamma (IFN-γ) level measured without antigen stimulation, serving as a negative control to account for non-specific background activity. The TB2 tube contains antigens designed to stimulate both CD4+ and CD8+ T-cell responses. By subtracting the NIL value from the TB2-stimulated IFN-γ level (TB2-NIL), clinicians can assess the specific immune response to TB antigens. A TB2-NIL value of 0.35 IU/mL or higher typically indicates a positive result, suggesting a TB infection. This method enhances the accuracy of TB diagnosis by distinguishing specific immune responses from background noise.

The presence of antibodies to Teff is an indication of food immune reactivity. The offending food and its known cross-reactive foods should be eliminated from the diet. Little work has been published on this food product. Due to the prevalence of its consumption by, and low incidence of diabetes, in Ethiopians, it can be postulated that Teff may be a healthy alternative grain for patients needing to consume a
low-glycemic diet. Teff has also been considered to be safe for Celiac patients, as it does not contain alpha-gliadin and has no cross-reactivity to the alpha-gliadin of wheat. If a recently diagnosed non-celiac gluten-sensitive patient exhibits high levels of antibodies to Teff, it may be due to the late introduction of Teff into the diet.

Tellurium (Urine) on Vibrant’s Total Tox-Burden reflects your recent body burden of this rare metalloid and is reported creatinine-corrected; a value ≤ 0.89 µg/g is typical for the reference population, while results above this cut-off suggest higher-than-expected recent exposure. Common sources are occupational or environmental—e.g., copper/lead refining by-products, electronics/thermoelectric materials, CdTe solar manufacturing, and telluride-containing alloys. Higher exposures may cause nonspecific symptoms (fatigue, nausea, metallic taste) and the classic garlic-like odor from dimethyl telluride excretion. Because urine reflects elimination, a single value can’t pinpoint timing/duration, and hydration status can influence results; don’t compare non-provoked results with provoked (chelator) tests. If elevated, focus on exposure reduction (controls/PPE and hygiene), avoid self-directed chelation, stay well hydrated, and consider clinician-guided retesting after changes.

Urinary tellurium (Te) provides an indication of recent or ongoing exposure to the metal, and endogenous detoxification to a lesser extent. The metal has no physiological function in the body, and urinary excretion is predominant.

Te is a very rare element that is a byproduct of milled copper. The use of Te in industrial applications has increased in scope and scale. Te may be used as an additive in steel and it is often alloyed to aluminum, copper, lead and tin. It is also used in the manufacture of solar panels (cadmium-telluride), cast iron, ceramics, vulcanized rubber, blasting caps, and glass production.

Free and weakly bound testosterone (FWBT), also referred to as bioavailable testosterone, is thought to reflect an individual's biologically active, circulating testosterone. FWBT includes free testosterone and testosterone that is bound to albumin. FWBT does not include sex hormone binding globulin-bound testosterone. The SHBG-bound fraction is biologically inactive because of the high binding affinity of SHBG for testosterone. The rapid dissociation of “weakly bound” testosterone from albumin results in the availability of essentially all albumin-bound testosterone for steroid-receptor interaction.

The measurement of free and weakly bound testosterone in women, when used in conjunction with the assay of the DHEA-S and SHBG, can be used to establish etiology of hirsutism.

Free and weakly bound testosterone (FWBT), also referred to as bioavailable testosterone, is thought to reflect an individual's biologically active, circulating testosterone. FWBT includes free testosterone and testosterone that is bound to albumin. FWBT does not include sex hormone binding globulin-bound testosterone. The SHBG-bound fraction is biologically inactive because of the high binding affinity of SHBG for testosterone. The rapid dissociation of “weakly bound” testosterone from albumin results in the availability of essentially all albumin-bound testosterone for steroid-receptor interaction.

The measurement of free and weakly bound testosterone in women, when used in conjunction with the assay of the DHEA-S and SHBG, can be used to establish etiology of hirsutism.

The marker “Testost., F+W Bound” stands for Testosterone Free and Weakly Bound. Free and weakly bound testosterone, also referred to as bioavailable testosterone, is thought to reflect an individual’s biologically active, circulating testosterone. It includes free testosterone and testosterone that is bound to albumin. It does not include sex hormone binding globulin-bound testosterone.

Free and weakly bound testosterone (FWBT), also referred to as bioavailable testosterone, is thought to reflect an individual's biologically active, circulating testosterone. FWBT includes free testosterone and testosterone that is bound to albumin. FWBT does not include sex hormone binding globulin-bound testosterone. The SHBG-bound fraction is biologically inactive because of the high binding affinity of SHBG for testosterone. The rapid dissociation of “weakly bound” testosterone from albumin results in the availability of essentially all albumin-bound testosterone for steroid-receptor interaction.

The measurement of free and weakly bound testosterone in women, when used in conjunction with the assay of the DHEA-S and SHBG, can be used to establish etiology of hirsutism.

The marker "Testosterone, Free, Calculated (Female)" is an important parameter in assessing various health conditions and understanding the hormonal balance in females. Testosterone, although typically associated with males, is also a vital hormone in females, playing crucial roles in muscle strength, bone density, and sexual function. Unlike males, where testosterone is the primary sex hormone, females produce it in much smaller quantities. Its levels in the female body can be indicative of various health conditions, making its measurement and understanding critical in medical practice.

Free testosterone refers to the fraction of testosterone that is not bound to proteins in the blood and is, therefore, available to tissues. The majority of testosterone in the bloodstream is bound to two proteins: sex hormone-binding globulin (SHBG) and albumin. The "free" portion of testosterone is biologically active, meaning it can interact with cells and potentially affect the body. Calculated free testosterone estimates the amount of testosterone that is not bound to SHBG or albumin, providing insights into the hormone's active levels. This calculation typically involves measuring total testosterone, SHBG, and sometimes albumin, using these values in a formula to estimate free testosterone levels.

Free testosterone is a key biomarker that measures the biologically active portion of testosterone circulating in the bloodstream. Unlike total testosterone, which includes both bound and unbound hormones, free testosterone represents the immediately available hormone that directly impacts physiological functions.

This test assesses the level of the hormone testosterone in your bloodstream. Testosterone, an androgen, is primarily responsible for the development of male characteristics. It is synthesized in the testes for males, ovaries for females, and the adrenal glands.

During puberty in males, testosterone induces several changes, including the growth of hair, muscles, penis, and testes, along with a deepening of the voice. It continues to be produced in adult males, promoting sex drive and aiding in sperm maturation.

Females also produce small amounts of testosterone in their ovaries, contributing to various bodily functions.

The pituitary gland in the brain regulates testosterone production by releasing signaling hormones such as luteinizing hormone.

Testosterone is the major androgen in the body. It is converted to dihydrotestosterone by 5-alphareductase, and to estradiol by aromatase.