Mechanism[ edit ] By definition, pericyclic reactions proceed through a concerted mechanism involving a single, cyclic transition state. Because of this, prior to a systematic understanding of pericyclic processes through the principle of orbital symmetry conservationthey were facetiously referred to as 'no-mechanism reactions'. However, reactions for which pericyclic mechanisms can be drawn often have related stepwise mechanisms proceeding through radical or dipolar intermediates that are also viable. Moreover, pericyclic reactions also often have metal-catalyzed analogs, although usually these are also not technically pericyclic, since they proceed via metal-stabilized intermediates, and therefore are not concerted.
Measurement and interpretation of proteinuria and albuminuria revised Gregory F. Proteinuria is a general term that describes the presence of any type of protein in the urine, such as albumin, globulins, and Bence Jones proteins.
Proteinuria of renal origin results from two major mechanisms: Albumin is the predominate protein in urine in dogs and cats in both health and renal disease. Type IV collagen within the basement membrane of the glomerular capillary wall restricts the filtration of most plasma proteins, primarily on the basis of molecular weight and size.
Albumin molecular weight 69, daltons and larger proteins are normally not present in large quantities in glomerular filtrate due to this glomerular selective permeability.
The negatively charged glomerular capillary wall further impedes the passage of negatively charged proteins like albumin. Smaller-molecular-weight proteins, as well as those positively charged larger proteins that do pass through the glomerular capillary wall, are almost completely reabsorbed by tubular epithelial cells.
Such reabsorbed proteins may be broken down and used by the epithelial cells or returned to the plasma as their constituent amino acids. Reabsorption of protein by tubular epithelial cells, however, has a transport maximum. Tubular proteinuria may occur if that maximum is exceeded e. Many laboratories confirm positive reactions for protein on the dipstick test with the sulfosalicylic acid SSA turbidimetric test.
The dipstick colorimetric test for proteinuria is inexpensive, easy to use, and primarily measures albumin, but sensitivity and specificity are relatively low. False-positive results are also common in both species with the dipstick but occur more frequently in cats than in dogs.
In addition to albumin, the SSA test can detect globulins and Bence Jones proteins to a greater extent than the dipstick test. False-positive results may occur if the urine contains radiographic contrast agents, penicillin, cephalosporins, sulfisoxazole, or thymol a urine preservativeand for other, unknown reasons.
The protein content may also be overestimated with the SSA test if uncentrifuged, turbid urine is analyzed. Because of the relatively poor specificity of conventional dipstick analysis, many reference laboratories will confirm a positive dipstick test result for proteinuria using the SSA test.
When both tests are performed simultaneously they should be interpreted in series both tests should be positive in order to consider the sample positive for albuminuriarather than in parallel fashion, to increase specificity.
The sensitivity and specificity of the dipstick and SSA tests for detection of albuminuria has also been evaluated in cats with CKD. In the case of a negative urine dipstick result the addition of the SSA test added little diagnostic value.
In addition, a positive dipstick reading for protein in the presence of hematuria or pyuria was often attributed to urinary tract hemorrhage or inflammation. However, in both situations this interpretation may not be correct.
Given the limits of the conventional dipstick test sensitivity, any positive result for protein regardless of urine concentration may be abnormal except in the case of false-positive results.
Likewise, hematuria and pyuria have an inconsistent effect on urine albumin concentrations: Detection of albuminuria Albuminuria can be measured by quantitative immunoassays at reference laboratories Antech Diagnostics and Heska Corporation.
Urine albumin concentrations can be adjusted for differences in urine concentration by dividing by urine creatinine concentrations. Alternatively, urine can be diluted to a standard concentration by using the urine specific gravity e.
In one study of dogs, normalizing urine albumin concentrations to a 1. Interpretation and follow-up of MA testing is critical. Like other tests for proteinuria, MA tests can be affected by lower urinary tract inflammation and therefore assessment of patient history and urine sediment changes is important.
A negative MA result is a useful finding because it obviates any concern about albuminuria until the next testing interval.
A positive test result is more complex and needs to be confirmed with follow-up testing approximately days later. If the second test is negative, the initial positive test was likely due to transient benign or physiologic albuminuria that is unlikely to have any long-term consequence for the patient.
If follow-up tests continue to be positive, more frequent monitoring and further investigation is indicated to verify whether proteinuria is persistent and show any changes in its severity.
Increases in magnitude of MA are likely indicative of active, ongoing renal injury, and should prompt further investigation to detect any infectious, inflammatory, or neoplastic disease that might be the underlying cause of renal disease. The prevalence of low-level albuminuria in dogs admitted for intensive care is higher than for other reported patient populations and appears to vary with different classifications of disease.
A large percentage of dogs that were euthanized or died had albuminuria, suggesting that, as in people, its presence may be a negative prognostic indicator.
Proteinuria may be caused by physiologic or pathologic conditions. Physiologic or benign proteinuria is often transient and abates when the underlying cause is corrected.Define interpretation. interpretation synonyms, interpretation pronunciation, interpretation translation, English dictionary definition of interpretation.
n. 1. The act or process of interpreting. the government's interpretation of events → L'interprétation qu'a le gouvernement des événements my interpretation of it → l.
Watch full episodes of Discovery shows, FREE with your TV subscription. Available anytime on any device. Start watching now! This list of MPhil and PhD theses submitted in the Department of Anthropology since , and of MA theses up to , has been compiled from departmental records, the catalogue card index of theses in the BLPES and (for very early theses) the index in the Senate House library, and the University of London's serial publication, Subjects of dissertations and theses (from ).
Measurement and interpretation of proteinuria and albuminuria (revised ). Gregory F. Grauer Manhattan, KS, USA. Introduction. Persistent proteinuria with an inactive urine sediment is likely marker of chronic kidney disease (CKD) in dogs and cats.
1 Recent evidence also suggests an association between renal proteinuria and progression of CKD in both species: the greater the magnitude of. Daniel J Klionsky University of Michigan, Department of Molecular, Cellular, and Developmental Biology, Ann Arbor, MI, USA; University of Michigan, Life Sciences Institute, Ann Arbor, MI, USA Correspondence [email protected], Kotb Abdelmohsen National Institute on Aging, National Institutes of Health, Biomedical Research Center, RNA Regulation Section, Laboratory of Genetics, Baltimore, MD.
On November 5, , a mass shooting took place at Fort Hood, near Killeen, Texas.
Nidal Hasan, a U.S. Army major and psychiatrist, fatally shot 13 people and injured more than 30 others. It was the deadliest mass shooting on an American military base. Hasan was shot and as a result paralyzed from the waist down.
Hasan was arraigned by a military court on July 20, and was charged with