Remember me on this computer. Enter the email address you signed up with and we'll email you a reset link. Need an account? Click here to sign up. Download Free PDF. Graham Basten. A short summary of this paper. Fascinating lighting offers an ininite spectrum of possibilities: Innovative technologies and new markets provide both opportunities and challenges.
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Select research publications 1. Blood folate status and expression of proteins involved in immune function, inlammation, and coagulation: biochemical and proteomic changes in the plasma of humans in response to long-term synthetic folic acid supplementation. J Proteome Res. Br J Cancer. Epub May 30 Download free eBooks at bookboon.
Associations between two common variants CT and AC in the methylenetetrahydrofolate reductase gene and measures of folate metabolism and DNA stability strand breaks, misincorporated uracil, and DNA methylation status in human lymphocytes in vivo.
Cancer Epidemiol Biomarkers Prev. Efect of folic Acid supplementation on the folate status of buccal mucosa and lymphocytes. It will also be useful to professionals undergoing continuing professional development CPD or changing to an extended role who require a background covering physiology and pathology for haematology and biochemistry.
To facilitate this, each chapter has an introductory paragraph guiding the reader to the example boxes if needed and a summary section. Chapter 1 examines how to interpret results, with the remaining broadly representing a section of the body or a disease type with chapter 9 as a summary. As this book is an introduction to the area, you may be inspired for further training and reading.
Study with the textbook using key concepts these are the headings and sub headings. List the key concepts and attempt to write a few words about each section, and then refer back to the text book. Similarly, deinitive diagnosis, prescribing, treatment, monitoring times are excluded; the reader should seek this information from their primary care provider or trusted sources.
Case studies are used throughout but should not be used as the basis for a diagnosis. Neither the author nor the publisher accepts any liability for the reader using the information in the book inappropriately.
Whilst true that in most modern hospitals much of the calculations in this chapter will be automated and produced by computer programmes, an understanding of the basic principles is to be encouraged. Increasingly and intuitively, this study has merged with certain aspects of haematology blood cells and liquid.
Typically a blood science service will have a laboratory manager who will oversee the production of reliable results, and will usually be state registered. Logistically, there will be areas for sample reception, analysis, reporting data and storage of material. Analytical error is caused by the service, typically the machine or process which produces the result. Physiological error is caused by people, typically how the blood is collected, whether the patient was fasted or taking medication.
Confusingly, two sets of sensitivity and speciicity exist in blood sciences; they have totally diferent meanings and refer to either analytical and physiological or diagnostic measures. Analytical sensitivity refers to the detection limit of the experiment.
As technology has developed it is increasingly easier to measure smaller quantities of material, although at small levels the accuracy and precision may be lower and this can be measured using quality control. A primary standard is of a known quantity and is oten produced externally with certiication, they are used to characterise the upper and lower parameters or sensitivity of the test. Oten labelled as high, low, calibrators, controls they can also be used to calibrate on-board sotware of automated analysers.
Hence the need for secondary standards which are usually samples of plasma, serum or whole blood to ensure that test is suitable and consistent in the chosen matrix. Figure 1.
H and L are primary standards see chapter 1. A common misconception is that a low CV is by default better than a higher one. It is used to evaluate for example, if the machine or indeed a diferent operator will give a diferent result at a diferent time. Typically, a national organisation will send the same sample to diferent laboratories accredited to produce blood results and measure how similar the returned result is.
Excellent online resources for both these plots exist, accessible by any good search engine, and will provide further reading. Test results for a patient sample which fall outside of this range are to be considered for rejection. On the Y-axis is the mean plus and minus 3 SD determined by the within batch, on the X-axis is the mean value for each between batch test. The red dot is a mean value which is outside the 3SD range and may be considered for rejection.
Each blue dot x10 is the mean value of the between batch over 10 days, a blue dot per day, this shows that this test is under reporting. Think about what a test that over reported may look like? Precision is how close repeated measures of the same sample lie, accuracy is how close the value reported is to the true value and bias describes variables which may afect precision and accuracy and lead to over and under reporting or large random background changes. In the remainder of the chapter issues caused by people will be explored.
Such as, how blood is collected and stored, the diference between plasma and serum, using reference ranges and clinical sensitivity and speciicity. Clearly these disadvantages do not justify the non-use of tourniquets but may be worth considering if results appear unlikely based on symptoms or unreliable.
Other problems include poor patient identiication, samples taking more than 72 hours to be transported to the service, incorrect temperature or not protected from light. To reduce this error each test will have a speciic blood collection protocol.
If blood is allowed to clot the liquid component is therefore called serum, if blood is prevented from clotting then the liquid component is called plasma FIG. In other words, a series of metabolic processes have occurred ater the sample was collected but before the sample was measured and this can lead to error in measures like potassium, phosphate, magnesium, aspartate aminotransferase and lactate dehydrogenase.
As we will see in alter chapters these are key measures of acute and chronic disease. Many nonpancreatic diseases, such as renal, hepatic, intestinal, and neoplastic diseases, can lead to increases in serum amylase and lipase activities. Steroid administration can also increase serum lipase activity and cause variable responses in serum amylase activity. Thus, in dogs, measurement of serum amylase and lipase activities are of limited usefulness for diagnosis of pancreatitis.
In cats, serum amylase and lipase activities are of no clinical value for diagnosis of pancreatitis. Although cats with experimental pancreatitis can show an increase in serum lipase activity and a decrease in serum amylase activity, these changes are not consistent in cats with spontaneous pancreatitis. In one study of 12 cats with severe forms of pancreatitis, not a single cat had serum lipase or amylase activity above the upper limit of the reference range.
Serum trypsin-like immunoreactivity TLI concentration measures mainly trypsinogen, the only form of trypsin circulating in the vascular space of healthy individuals. However, trypsin, if present in the serum, is also detected by these assays.
Serum TLI concentrations can be measured by species-specific assays that have been developed and validated for both dogs and cats. In healthy animals, serum TLI is low, but during pancreatitis an increased amount of trypsinogen leaks into the vascular space, which can lead to an increase in serum TLI concentration.
Trypsin that has been prematurely activated may also contribute to this increase. However, both trypsinogen and trypsin are quickly cleared by the kidneys. Thus, the serum half-life for TLI is short, and a significant degree of active inflammation is required to increase serum TLI concentration. Because of the limited sensitivity of serum cTLI and fTLI concentrations for canine and feline pancreatitis, respectively, and because only a limited number of laboratories measure these assays routinely, serum TLI concentration is of limited usefulness for diagnosis of pancreatitis in dogs and cats.
Pancreatic lipase immunoreactivity PLI concentration measures the concentration of classical pancreatic lipase in the serum. This is in contrast to serum lipase activity, which measures the enzymatic activity of all triglyceridases present in the serum, regardless of their cellular origin.
Serum PLI is highly specific for exocrine pancreatic function. Also, serum PLI is far more sensitive for diagnosis of pancreatitis than any other diagnostic test currently available. A patient-side semiquantitative assay for diagnosis of canine pancreatitis is also available.
A test spot that is lighter in color than the reference spot suggests that pancreatitis can be excluded. A test spot darker in color than the reference spot raises the suspicion of pancreatitis and should prompt the clinician to measure a serum cPLI concentration in the laboratory.
However, none has been shown to be of clinical usefulness. In the past, several fecal tests have been used to diagnose exocrine pancreatic insufficiency EPI.
However, in light of wide availability of tests to diagnose EPI, microscopic fecal examination is no longer justified. Fecal proteolytic activity had been used to diagnose EPI in small animals for several decades.
Most of these methods, particularly the radiographic film clearance test, are unreliable. One method, which uses pre-made tablets to pour a gelatin agar, is considered most reliable. However, false-positive as well as false-negative results have been reported. The clinical use of fecal proteolytic activity is limited to species for which more specific assays to estimate pancreatic function are not available and in areas where the more accurate and sophisticated tests are not available.
Assays for TLI measure trypsinogen circulating in the vascular space. In healthy animals, only a small amount of trypsinogen is present in serum. However, in dogs and cats with EPI, the number of pancreatic acinar cells is severely decreased. Serum TLI concentration decreases significantly and may even be undetectable. The reference range for TLI in dogs is 5.
This is probably because of the functional redundancy of the GI tract. At the same time, many dogs and cats with chronic diarrhea and weight loss have mild decreases in serum TLI concentration. Most of these animals have chronic small-intestinal disease and should be investigated accordingly. However, a small number of these dogs and cats may have EPI. If there is no evidence of small-intestinal disease in such patients, a trial therapy with pancreatic enzymes and reevaluation of serum TLI concentration after 1 mo is indicated.
However, initial studies showed there is a small degree of overlap in serum PLI concentrations between healthy dogs and dogs with EPI, making the measurement of PLI slightly inferior to that of TLI for accurate diagnosis. In view of these findings, PLI assays for both dogs and cats have been optimized toward higher concentrations, and the current assays are no longer suitable for diagnosis of EPI in dogs or cats. A fecal canine elastase concentration assay has been developed and validated but is inferior to the widely used TLI measurement.
Most biochemistry tests can be performed on either serum or heparinized plasma. A few eg, insulin require serum, whereas potassium is best measured on heparin plasma separated immediately after collection. Suitable collection tubes with and without anticoagulant are available commercially. Plastic tubes are satisfactory for blood in anticoagulant, but clotted blood must be collected either into glass tubes or plastic tubes specially coated to prevent the clot from adhering to the vessel walls.
Samples for biochemical analysis should be separated as soon as possible after collection to minimize artifacts caused by hemolysis and leakage of intracellular fluid components eg, potassium out of the cells.
Samples in anticoagulant may be centrifuged immediately, but clotted samples need at least 30 min to allow the clot to form. Proprietary gels or plastic beads assist with separation, and these may be incorporated into the collection tube or added before centrifugation.
Larger bucket-type centrifuges will accept almost any type or size of tube, but the rotors require careful balancing. They should be spun at 3, rpm for 10 min. Dual-purpose, high-speed microhematocrit centrifuges are favored for in-practice use, because they separate samples more quickly and the same machine can be used to measure PCV. However, they can handle only a limited range of small-volume tubes.
The new tube must be adequately labeled. Samples may then be sent to a professional laboratory or analyzed in the practice. A number of biochemical analytes may be estimated in the practice without the need for large analytical instruments. Total protein level is measured by refractometry, using the same instrument as is used to measure urine specific gravity, provided the instrument has a total protein scale.
It is also valid for protein measurement of ascitic and pleural fluids. Urea level may be estimated by chromatographic reaction strips, which correlate well with standard laboratory methods.
A dedicated reflectance meter for urea estimation is not available. Glucose meters for use on whole blood are widely available for home use by human diabetic patients. These yield acceptably accurate results on animal blood, although an unexpected hypoglycemia should be confirmed by a professional laboratory.
Fresh whole blood may be used, but fluoride blood or plasma is the preferred sample if analysis is not immediate. This can be achieved by using the ketone patch of a urine dipstick, giving a qualitative result. Triglyceride levels may be visualized in a plasma or serum sample as lipemia.
If the milkiness rises to the top of the tube on storage, chylomicrons are present. Otherwise, the milkiness is caused by triglycerides. This is a qualitative judgment but is nevertheless useful, especially in equine patients. Chest Pain Profile. Cholesterol Familial Hypercholesterolaemia. Complement Factor H. Cortisol Binding Globulin. Creatinine Clearance.
Crosslaps Serum DPD. Cyclosporin Monoclonal. Deoxypyridinoline DPD — Serum. Deoxypyridinoline DPD — Urine. Diabetic Profile 1. Diabetic Profile 2. Diamine Oxidase Activity. Electrolytes Urine. Eosinophil Cationic Protein. Faecal Fat 1 Day Collection. Faecal Lactoferrin. Faecal Sugar Chromatography. Fat Globules in Faeces. Fibrotest Liver Fibrosis. GalactosePhosphate Uridyltransferase. Gall Stone Analysis. Haemosiderin Urine.
Homocysteine Quantitative. Homocysteine Urine. Homovanillic Acid HVA. Hydroxybutyrate Dehydrogenase. Immunoglobulin E — Total. Insulin-Like Growth Factor 2. Iron TIBC included.
Iron Overload Profile. Iron Status Profile. Lactate Dehydrogenase LDH. Lactate Pyurvate Ratio. Lactose Tolerance Test. Lipoprotein Electrophoresis. Liver Fibrosis Fibrotest. Liver Function Tests.
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