Diagnostische Eigenschaften eines neuen California-Mastitis-Tests

Gegenstand und Ziel: Um Sekretionsstörungen der bovinen Milchdrüse bereits frühzeitig in praxi identifizieren zu können, ist es notwendig, ein Testsystem mit einer hohen Sensitivität einzusetzen. Im Rahmen der vorliegenden Studie sollte daher untersucht werden, inwieweit durch die Verwendung eines Reagenz mit einer optimierten Rezeptur die Sensitivität des California-Mastitis-Tests im Vergleich zu einem kommerziell verfügbaren Produkt verbessert werden kann, sodass sich bereits Überschreitungen der Zellzahl von 100.000 Zellen/ml sicher erkennen lassen. Material und Methoden: In vitro wurden die Viskositäten von Gemischen aus Testmilchen mit standardisierten somatischen Zellgehalten (50.000-800.000 Zellen/ml) und Testreagenzien bestimmt. Insgesamt 50 Viertelanfangsgemelksproben von Tieren, die keine Anzeichen einer klinischen Mastitis aufwiesen, wurden geblindet mit dem California-Mastitis-Test unter Verwendung beider Testreagenzien untersucht. Sensitivität und Spezifität der Testsysteme wurden ermittelt. Ergebnisse: Mit zunehmendem somatischem Zellgehalt stieg die Viskosität der Gemische zu Beginn der rheologischen Messung. Bei einem Zellgehalt der Milch von 50.000 Zellen/ml ergab sich eine mittlere Viskosität von 3,20 mPa*s (kommerziell verfügbarer Test) bzw. 2,69 mPa*s (optimiertes Testreagens). Bei einem Milchzellgehalt von 100.000 Zellen/ml stieg die Viskosität auf 3,43 mPa*s (kommerziell verfügbarer Test) bzw. 4,58 mPa*s (optimiertes Testreagens) an. Die Sensitivität betrug bei Verwendung des kommerziell verfügbaren Testreagens 76,7% und unter Einsatz des optimierten Testreagens 97,7% bei einer Zellzahlgrenze von 100.000 Zellen/ml als Übergang vom physiologischen Zustand zu einer Sekretionsstörung. Schlussfolgerung und klinische Relevanz: Das optimierte Testreagens erlaubt im Vergleich zu dem kommerziell verfügbaren Reagens die frühzeitige Erkennung zellzahlhoher Viertel bzw. Tiere. Die Ergebnisse machten deutlich, dass das Ablesen des Testresultats direkt nach der Reaktion erfolgen muss.

[Diagnostic characteristics of a new California Mastitis Test]

OBJECTIVE

For the early detection of udder health disorders in praxi, it is necessary to use a method with high sensitivity. The aim of the present study was to investigate the sensitivity of a commercial Califor- nia Mastitis Test and a new reagent which was optimised for the detection of udder health disorders with somatic cell counts > 100,000 cells/ml.

MATERIAL AND METHODS

The viscosity of mixtures of test milks with standardised somatic cell counts (50,000-800,000 cells/ml) and test reagents were analysed in vitro. A total of 50 quarter fore- milk samples from cows without signs of clinical mastitis were investigated using both California Mastitis Test reagents. Sensitivity and specificity were calculated.

RESULTS

The viscosity of mixtures increased with a higher somatic cell count. At a somatic cell count of 50,000 cells/ml, the mean viscosities were 3.20 mPa*s (commer- cial product) and 2.69 mPa*s (optimised reagent). At a somatic cell count of 100,000 cells/ml the viscosities increased to 3.43 mPa*s and 4.58 mPa*s, respectively. At a somatic cell count threshold of 100,000 cells/ml, marking the transition of the physiological status into a secretion disorder, the sensitivity of the commercial test was 76.7% and that of the optimised test was 97.7%.

CONCLUSION AND CLINICAL RELEVANCE

The optimised California Mastitis Test allows - compared to the commercial product - the early detection of quarters or animals with high somatic cell counts. The results of the study indicate that the test result has to be evaluated immediately after the California Mastitis Test reaction.

Unusual manifestation of a multiple myeloma in the hyoid bone

The most common manifestation of plasma cell neoplasms is multiple myeloma. Solitary and localized tumours in the form of solitary plasmacytoma of the bone or extramedullary plasmacytoma are rare. In the late stages of multiple myeloma, bulky bone tumour infiltrates may be found which may be the primary clinical manifestation of the previously unknown malignancy. We report a case of a hyoid bone tumour with extramedullary plasma cell infiltrates in the oropharynx in multiple myeloma.

Nutritional impact on the plasma metabolome of rats

Metabolite profiling (metabolomics) elucidates changes in biochemical pathways under various conditions, e.g., different nutrition scenarios or compound administration. BASF and metanomics have obtained plasma metabolic profiles of approximately 500 compounds (agrochemicals, chemicals and pharmaceuticals) from 28-day rat studies. With these profiles the establishment of a database (MetaMap(®)Tox) containing specific metabolic patterns associated with many toxicological modes of action was achieved. To evaluate confounding factors influencing metabolome patterns, the effect of fasting vs. non-fasting prior to blood sampling, the influence of high caloric diet and caloric restriction as well as the administration of corn oil and olive oil was studied for its influence on the metabolome. All mentioned treatments had distinct effects: triacylglycerol, phospholipids and their degradation product levels (fatty acids, glycerol, lysophosphatidylcholine) were often altered depending on the nutritional status. Also some amino acid and related compounds were changed. Some metabolites derived from food (e.g. alpha-tocopherol, ascorbic acid, beta-sitosterol, campesterol) were biomarkers related to food consumption, whereas others indicated a changed energy metabolism (e.g. hydroxybutyrate, pyruvate). Strikingly, there was a profound difference in the metabolite responses to diet restriction in male and female rats. Consequently, when evaluating the metabolic profile of a compound, the effect of nutritional status should be taken into account.

Influence of Moisture-Uptake on Mechanical Properties of Polymers Used in Microelectronics

Polymers are currently considered as a possible alternative to silicon dioxide in the fabrication of interlevel dielectrics. To penetrate mainstream semiconductor device fabrication polymers have to meet a number of requirements regarding their long-term stability. One aspect is the mechanical stability of integrated polymer films under changing climatic conditions. In the present work, the impact of ambient moisture on the mechanical properties of thin polymer films (PI, BCB, and PFCB) was investigated. The sorption of water molecules in these materials typically causes an anisotropic volume expansion, resulting in increased mechanical film stress if the film is physically constrained by adjacent inorganic structures. Especially polyimides show both considerable moisture uptake and large changes in the mechanical film stress, while BCB and PFCB are virtually insensitive to ambient moisture. In the paper, experimental data (water uptake, in-plane swelling, out-of-plane swelling) are presented and discussed in detail.

Sensitivity and specificity of autoantibody tests in the differential diagnosis of lupus nephritis

Several studies have investigated the potential of various autoantibody tests in the diagnosis of systemic lupus erythematosus (SLE). Many lupus patients initially present with glomerulonephritis. In that clinical situation the main differential diagnosis are other forms of glomerulonephritis. In this study the diagnostic value of nine test kits for autoantibody against ANA, dsDNA, circulating immune complexes, C1q, nucleosomes, histones and Sm as well as C3 and C4 levels was evaluated in 39 patients with biopsy-proven lupus nephritis in comparison to 43 patients suffering from other forms of glomerulonephritis. The most useful test was an anti-nucleosome antibody enzyme-linked immunosorbent assay (ELISA) with a sensitivity of 90% and a specificity of 88%. All tests for anti-dsDNA antibodies (Crithidia luciliae Anti-dsDNA, BINDAZYME Anti-dsDNA, FARRZYME high avidity Anti-dsDNA) were of moderate sensitivity and very good specificity. Decreasing the cut-off for the conventional anti-dsDNA ELISA (BINDAZYME) considerably increased its sensitivity (87%) without loss of specificity (90%). Tests for anti-C1q and immune complexes performed worse than the antidsDNA tests. As anti-histone and Sm antibodies are present only in a minority of lupus nephritis patients they are of limited value in diagnosing the disease. In conclusion, testing for anti-nucleosome antibodies and the conventional anti-dsDNA ELISA with lower cut-off provide the best diagnostic aids for differentiation of lupus nephritis from other forms of glomerulonephritis. Lupus (2009) 18, 1276—1280.