biologic specimen and biologic variation.pptx

Microbiology

1. Types of biologic specimen and biologic variation

2. Definition of terms Specimen Sample

3. Types of Specimen 1. Blood Specimen 2. Urine and saliva specimen 3. Cerebrospinal fluid specimen 4. Tissue specimen, any one, both living and dead tissues for forensic studies, skin, various organs, 5. Other body Fluid specimen; tears, semen, ascitic fluid, pleural effusion, gastric fluid from larvage 6. Other human biological specimen; Stool, sputum, hair

4. Biological variation Biological variation (BV) is all about the physiological fluctuation around a homeostatic set point, this is normal for all blood measurands (analytes). That variation might influence the clinical relevance of the changes that are observed in the serial results from the measurement of an individual. Biological variation is represented mathematically by the coefficient of variation (CV) and occurs within each individual (CV I ) and between individuals in a population (CV G

5. Biological variation The concept here is based on the fact that the level of analytes are not fixed in biologic specimen And this concept also helps us to determine when to take specimen for certain analytes.

6. Types Types: within subject and between subject Within subject has to do with natural rhythms and life patterns with some genetic uniqueness and predisposition. (reference ranges come to play here) Between subjects (also involve reference intervals) has to do with variations involving sex, age, race, pregnancy.

7. Biological rhythms Biological rhythm is a phrase often used interchangeably with circadian rhythm. These rhythms are a series of bodily functions regulated by your internal clock. They control cycles like  sleep  and wakefulness, body temperature, hormone secretion, and more.  Light and darkness have a strong role to play.

8. Diurnal: this has to do with night and day variations Circadian; this has to so with 24 hours cycles Ultradian; less than 24 hours Infradian /Circalunar: this has to do with a month cycle Circannual: this has to do with yearly cycles The first two are tied most affected by light and send signals to your brain on what to do based on light and darkness.

9. Beyond sleep these cycles and rhythms control other things such as Metabolism Heart rate Blood pressure Body temperature Hormone levels Urine production appetite hormone levels alertness daily performance reaction times

10. Diurnal: leptin and ghrelin Circadian; cortisol, growth hormone, TSH (high between 12 and6am) testosterone, Ultradian; Glucose and triglycerides ( based on meals) Infradian /Circalunar: menstrual cycle Circannual: Vitamin D ( and bone turnover in people in temperate regions.

11. References 1. Rossi G, Liu KF, Kershaw H, Riddell D, Hyndman TH, Monks D, Musk GC. Biological Variation in Biochemistry Analytes in Laboratory Guinea Pigs ( Cavia porcellus ). Vet Sci. 2023 Oct 17;10(10):621. doi : 10.3390/vetsci10100621. PMID: 37888573; PMCID: PMC10610888. 2. https://www.webmd.com/a-to-z-guides/what-are-biological-rhythms