Spinal fluid specimen

In most instances the specimens will be self-evident (e.g., samples of blood, plasma, serum, urine, spinal fluid, aqueous humor, organs, tissues, and tissue fractions that are taken from a test system with the intention of performing an examination or analysis). In other instances the definition may not be as clear. For example, the assay plates used in the mammalian cell transformation assay and the mammalian point mutation assay are considered specimens even though they bear many of the attributes of a test system. For these assays, the originally plated cells plus media and excipients are the test system. After treatment with the test or... 

The function of clinical chemistry in toxicology (as well as in human and veterinary medicine) is to provide, via laboratory analysis, evaluations of the qualitative and quantitative characteristics of specific endogenous chemical components present in samples of blood, urine, feces, spinal fluid, and tissues. The purpose is to help identify abnormal or pathological changes in organ system functions. The most common specimens used in clinical chemistry are blood and urine, and many different tests exist to test for almost any type of chemical component in blood or urine for example, blood glucose, electrolytes, enzymes, hormones, lipids (fats), other metabolic substances, and proteins. The tests used were all initially applied to human clinical medicine, and may not possess the same utility when performed as part of nonclinical toxicity studies in a wide variety of other species. 

Up to 20 mL of spinal fluid can be safely removed from an adult, although this amount is not usually required. Antiglycolytic agents usuaEy are not added to the tube for glucose measurement rapid processing of specimens, a cEn-icai requirement for tests on spinal fluid, ensures that little metaboEsm of glucose occurs even in the presence of many bacteria. To allow proper interpretation of spinal fluid glucose values, a simultaneous blood specimen should be obtained. 

Blood specimens are recommended for investigation of aminoacidopathies because amino acid concentrations are fairly stable in blood, urine amino acids analysis, on the other hand, is appropriate for disorders of amino acid renal transport such as cystinuria. Amino acid analysis in cerebral spinal fluid may be appropriate to aid in diagnosis (i.e., nonketotic hyperglycinemia) and management (i.e., cerebral amino acid disorders) of various IMD. The composition of an... 

Because CSF is not a homogeneous mixture, being derived from multiple sources, it is particularly important to keep precise track of the volume of CSF that is removed. Given the various gradients in concentration of some analytes, which are known to exist along the neuraxis, one should compare the same locus in specimens from different individuals. In humans, for instance, the first 20 ml of spinal fluid comes from the spinal cord, whereas, say, the 15th... 

An important part of the chemical enterprise is the chemical analysis of human specimens, often called clinical chemistry. Our medical system depends tremendously on these clinical tests, which have been developed hy chemists over many years. Clinical chemists routinely handle human specimens, such as hlood, serum, plasma, urine, sahva, spinal fluid, or feces, to provide data that help physicians and other health care providers determine medical treatments. There are many hundreds of these types of analytical methods. Some are automated and some have to he performed individually hy a chemist or other trained professional. 

Within a palette of the samples for organic and biological analysis, both CMCPEs and CP-biosensor have been employed for determination of a wide variety of compounds in (i) soft drinks (ii) alcoholic beverages (beers, ciders, and wines) (iii) vegetable oils (iv) food dyes, coloring additives, and antioxidants (v) industrial detergents and plastics and (vi) human tissues and fluids (kidney and liver cuts, spinal fluid, whole blood, serum, urine, and saliva). Among less frequently analyzed (vii) environmental samples, the dominant specimens were, for example, natural and industrial waters (see [4, 5, 33] and table surveys therein). 

For urine, spinal fluid, or other body fluids, undiluted specimens submitted for test may be diluted according to the expectation of potency range, as calculated from average data yielded on the dosage regimen used. 

Despite the relatively large number of papers that have appeared on filter paper electrophoresis, the amount of new information obtained with this procedure has been fairly small. The reason for this is that most people have applied the procedure to serum for clinical purposes, and analyses by free electrophoresis in this field have been carried out in the past in a far more quantitative manner. The method has proved more useful for other biological fluids, where it is difficult to obtain sufficient material for examination by free electrophoresis. A good example of this is the case of spinal fluid, concerning which considerable new information has been obtained by the use of paper electrophoresis (5,47,62). This has also proved true of the proteins in urine a large number of specimens has been studied... 

A patient underwent a surgical procedure to remove a cancerous eye, A nurse set everything up for the case. To prepare a container for the surgical specimen, she poured glutaraldehyde (preservative) into a medicine glass and placed it on the sterile field, Excess spinal fluid had been removed from the patient to reduce cerebral pressure because the malignancy had spread to his brain. The spinal fluid was in another unlabeled, identical, medicine glass also on the sterile field. 

Many errors can occur during the collection, processing, and transport of biological specimens. Minimizing these errors win result in more reliable information for use by healthcare professionals. Examples of biological specimens that are analyzed in clinical laboratories include whole blood serum plasma urine feces saliva spinal, synovial, amniotic, pleural, pericardial, and ascitic fluids and various types of solid tissue. The National Committee for CMnical Laboratory Standards (NCCLS) has published several procedures for collecting many of these specimens under standardized conditio ns.In addition, the NCCLS has published documents related to sample collection and analysis for specialized tests, such as sweat chloride (see also Chapter 27). 

The skin is cleaned and anesthetized as for other similar procedures, and lOmL of fluid is aspirated into a syringe connected to the spinal needle that is typically used. Sterile containers such as polypropylene test tubes or urine cups are used to transport the fluid to the laboratory. If a specimen is for the determination of the lecithin-sphingomyelin (L/S) ratio, the container is immediately placed in ice if it is for spectrophotometric analysis, the specimen should be transferred to a brown tube or bottle to prevent photodegradation of bilirubin. Alternatively the specimen container may be wrapped in aluminum foil. 

CSF is secreted by the choroid plexuses, around the cerebral vessels, and along the walls of the ventricles of the brain. It fills the ventricles and cisternae, bathes the spinal cord, and is reabsorbed into the blood through the arachnoid villi. CSF turnover is rapid, exchanging totally about four times per day. More than 80% of CSF protein content originates from plasma by ultrafiltration and pinocytosis the remainder is from intrathecal synthesis. The lowest concentration of total protein and the smallest proportion of the larger protein molecules are in the ventricular fluid as the CSF passes down to the lumbar spine (from which site specimens are usually collected), the protein concentration increases. This difference in concentration at different levels of the CNS is illustrated by the following reference intervalsd ... 

Exactly the same technique (headspace GC) can be applied for the determination of alcohol concentration in other biological specimens (urine, spinal-column fluid, or fluid from the eyes), with the only difference being the standard solutions. 

Marcet s publications on body fluids, including cerebro-spinal and dropsical fluids, are of biochemical importance, but his most interesting discovery in this field concerned a specimen of urine turning black in a case of alcap-tonuria the substance involved was called alkapton (from alkali, and Koirreiv to drink up) by Boedeker (1859). It is homogentisic acid, 2 5-dihydroxy-... 

The fluid made in the choroid plexus of the ventricles of the brain and secreted from them into the subarachnoid space around the brain and spinal cord. Specimens for laboratory examination are usually obtained from a lumbar puncture and they may be examined in a number of ways ... 

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