The ZRT Laboratory Blog

The ZRT Blog is an extensive resource for patients and health care providers searching for health and hormone testing information. Here, you can read about ZRT’s cutting edge research, advances in testing, wellness advice, and health industry highlights.

Research Puts the "R" in ZRT

Posted by Margaret Groves on Friday, 15 April

ZRT scientist working on urine testing machine

I have to admit, I believe that "research" is one of those words that I think is often misused today.

I started my own career in a cancer research lab, continued it in a pharmaceutical company research lab, and then got into medical information research and scientific writing, which meant using a range of medical literature databases and complex searching strategies.

My early research career was back in the days before we had personal computers, so many hours – in between tending to assays and experiments (as well as late in the evening) – were spent thumbing through the pages of massive volumes of Index Medicus, the print version of Medline, in various university libraries to find relevant publications.

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How Reference Ranges Determine a "Normal" Lab Test Result

Posted by Margaret Groves on Friday, 13 November

'Abnormal' on a chalkboard with 'Ab' crossed out and 'Normal' underlinedCLIA-certified testing laboratories such as ZRT are required to provide reference ranges as an aid to interpretation of test results.

Ideally, reference ranges provide the expected range of values for a healthy population. When methodology and equipment is identical for testing a particular analyte among different laboratories, reference ranges for that analyte should be the same.

However, when methodologies or equipment for the same test differ somewhat from lab to lab, each lab must provide its own reference range established with its own methods. These ranges are usually very close, but may differ slightly depending on method. An example would be testing testosterone in blood or saliva by extraction and LC-mass spectrometry vs. direct testing by immunoassay.

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Clearing up the Confusion about Reverse T3: Part 2. The Role of Reverse T3 in Thyroid Assessment

Posted by Margaret Groves on Friday, 08 May

Doctor stethoscope with "Thyroid" written on a signPart 2

As more health care practitioners have understood the need to assess thyroid function based on what is going on at the cellular level, there has been an increasing demand for testing of reverse T3 (rT3), a hormone sometimes referred to as the “hibernation hormone.” However, there is also much confusion about how it fits into the picture of thyroid function, and controversy regarding whether or not there is a clinical utility for this test in patients suffering from thyroid imbalance symptoms.

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Clearing up Confusion about Reverse T3: Part 1. The Deiodinases & Thyroid Hormone Bioavailability

Posted by Margaret Groves on Monday, 04 May

X-Ray of Thyroid gland

Part One

Thyroid hormones are essential for the normal metabolic functioning of all tissues in the body, and a wide array of symptoms are therefore associated with abnormalities in thyroid hormone production and activation. Even when apparently adequate amounts of thyroxine are produced by the thyroid gland, thyroid function is profoundly affected by anything that disrupts conversion of thyroxine (T4) to the active thyroid hormone, triiodothyronine (T3). This conversion takes place primarily at the cellular level within tissues; only 20% of circulating T3 is generated by conversion of T4 within the thyroid gland itself.

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