Passive measurement of isotopes to monitor health

• US 5,912,178 A
• Filed: 02/16/1994
• Issued: 06/15/1999
• Est. Priority Date: 02/16/1994
• Status: Expired due to Term

• Current Assignee: Wisconsin Alumni Research Foundation (University of Wisconsin System)
• Original Assignee: Wisconsin Alumni Research Foundation (University of Wisconsin System)
• Inventors: Porter, Warren P., Treichel, Isabel W., Cook, Mark E.
• Primary Examiner(s): BHAT, NINA NMN
• Application Number:
  US08/197,416
• Time in Patent Office: 1,945 Days
• Field of Search: 436/57, 436/55, 436/56, 436/804
• US Class Current: 436/55
• CPC Class Codes: C12Q 1/00 Measuring or testing processes involving enzymes, nucleic acids or microorganisms measuring or testing apparatus with condition measuring or sensing means, e.g. colony counters, C12M1/34; Compositions therefor; Processes of preparing such compositions
• CPC Class Codes: G01N 33/48 Biological material, e.g. blood, urine G01N33/02, G01N33/26, G01N33/44, G01N33/46 take precedence; Haemocytometers counting blood corpuscules distributed over a surface by scanning the surface G06M11/02
• CPC Class Codes: G01N 33/50 Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing measuring or testing processes involving enzymes or microorganisms, compositions or test papers therefor; processes for forming such compositions, condition responsive control in microbiological or enzymological processes C12Q
• CPC Class Codes: Y10T 436/12 Condition responsive control
• CPC Class Codes: Y10T 436/13 Tracers or tags

Abstract

Methods and apparatus are disclosed for determining the presence of a catabolic state in an organism (or collection of organisms) by measuring changes in isotopic ratios in biological materials obtained from them. Preferably, ¹³ C/¹² C ratios are monitored for isotopically unenriched animals, such as by testing changes in the ratio in blood or breath.

Claims

1. A method of determining the presence of a catabolic state in an essentially isotopically enriched animal, comprising the steps of:

collecting a sample selected from the group consisting of breath, whole blood, blood immunoglobin, hemoglobin, urine, hair tissue, feathers, horns, hooves, nails, skin, shells and membranes from the animal;

measuring the relative amount of a first isotope to a second isotope in the sample;

the isotopes being the pair ¹³ C and ¹² C, or being the pair ¹⁵ N and ¹⁴ N;

comparing said measured relative amount of the sample with a relative amount of said pair isotopes in a comparison specimen other than the sample; and

determining from the comparison step whether a catabolic state is present in the animal wherein the change in the isotope ratios either increasing or decreasing is indicative of a catabolic state.

2. The method of claim 1, wherein at least one relative amount is determined using a mass spectrometer.

3. The method of claim 1, wherein the pair of isotopes are ¹³ C and ¹² C.

4. A method of determining the presence of a metabolic state in an essentially isotopically unenriched population of at least a plurality of animals or microorganisms in an enclosure, comprising the steps of:

collecting a sample of air from the enclosure;

measuring the relative amount of a first isotope to a second isotope in the sample;

the isotopes being the pair ¹³ C and ¹² C, or being the pair ¹⁵ N and ¹⁴ N;

comparing the measured relative amount with a warning level relative amount of said pair of isotopes; and

determining from the comparison whether a catabolic state is present in the population.

5. The method of claim 4, wherein the pair is ¹³ C and ¹² C.

6. The method of claim 5, wherein the enclosure is an animal housing facility.

7. The method of claim 6, wherein the relative amount for the sample is measured using a mass spectrometer.