Determination of very-long-chain fatty acids in plasma by a simplified gas chromatographic—mass spectrometric procedure

The concentration of very-long-chain fatty acids (VLCFA) (straight chain, more than 22 carbon atoms) in plasma or in cultured fibroblasts is one of the most important diagnostic criteria for the diagnosis of the peroxisomal disorders. A sensitive method for VLCFA assay in plasma, using small sample volume and a simplified procedure, is described. After adequate extraction and derivatization, methyl esters of VLCFA are separated, identificated and quantified by gas chromatography—mass spectrometry (GC—MS). The method is sensitive, reproducible, accurate and relatively simple. GC—MS equipment used for routine organic acid analysis can be used.     

Chemotactic Behavior of Azotobacter vinelandii

Chemotaxis was exhibited by Azotobacter vinelandii motile cells. Exposure of cells to sudden increases in attractant concentration suppressed the frequency of tumbling and resulted in smooth swimming. Cells responded chemotactically to a chemical gradient produced during metabolism. Motility occurred over a temperature range of 25 to 37°C with an optimum pH range of between pH 7.0 and 8.0. The average speed of motile cells was determined to be 74 μm/s or 37 body lengths per s. The speed of cells appeared to increase as a function of attractant concentration. Chemotactic systems for fructose, glucose, xylitol, and mannitol were inducible. A. vinelandii exhibited chemotaxis for a number of compounds, including hexoses, hexitols, pentitols, pentoses, disaccharides, and amino sugars. We conclude from these studies that A. vinelandii exhibits a temporal chemotactic sensing system.     

Isolation of selective 3H-chlornaltrexamine-bound complexes,possible opioid receptor components in brains of mice

The nonequilibrium narcotic antagonist, chlornaltrexamine (CNA) was used to bind selectively and covalently pioid specific sites on brain membrane preparations. Selective binding of [³H]CNA occured with a saturation maximum of 185 fmol/mg protein. Bound [³H]CNA was extracted with Triton X-100, dialyzed against Brij 36T, precipitated with trichloroacetic acid and chromatographed on an ultrogel AcA 22 column. The elution profile suggests that this extract contains a minimum of four selective [³H]CNA complexes. At least two of these complexes migrate in a single large peak. Column calibration showed that this peak eluted at 590,000 daltons. One of these specific [³H]CNA complexes elutes at the elution volume of the column and is dialyzable. Finally, putative aggregate of these complexes elutes with the void volume.     

Les échos de la phase aquitano-burdigalienne dans la coupe de Dellaca Bianca (Val Scrivia,bassin Liguro-piémontais,Italie)

The geologic section of the Torrente Scrivia in 061 the vicinity of Rigoroso is generally reported as an conformable sequence in Oligocene and Miocene strata.In fact, it has suffered important reworkingsduring Lower Miocene and this event is not only evident in sedimentology but also in paleontology. Locally, these events reflect tectonic motions more strongly marked in the north-eastern part of the ligurian piemontese basin.Consequently, the result is that the geologicsection concerned could not be satisfactory referring to Lower Miocene.     

The immune response of allophenic mice to the synthetic polymer GLΦ

The immune response of allophenic mice of type C57BL/6(A × SJL) F₁ to GL administered in complete Freund's adjuvant was tested. Control mice of the three strains C57BL/6, A, and SJL are all nonresponders to this antigen. However, the F₁ generations of C57BL/6 × A, C57BL/6 × SJL, and A × SJL were all responders to the antigen, so that the complementarity of at least two genes is confirmed. The allophenic mice showed no further complementation beyond the F₁ generation, a result which may argue against the possibility that more than two genes control the response to GL in these mouse strains. Characterization of the allophenic mice over several months showed that they exhibit chimeric drift, both in their coat color and in peripheral white blood cell population. There is no apparent correlation of coat color to the lymphocyte composition of the mice at any one time. The mice are true chimeras, since killing of the two populations of white blood cells with two different anti-H-2 sera produced a 100 percent killing. The immune response of individual allophenic mice to GL showed a good correlation to the number of A × SJL lympho-cytes in the animal.Abbreviations used in this paper are GL an amino acid polymer of 57 %l-glutamic acid, 38%l-lysine, and 5%l-phenylalanine - GLT¹⁵ an amino acid polymer ofl-glutamic acid,l-lysine, and 15 %l-tyrosine - (T,G)-A-L an amino acid polymer having a polylysine backbone with side chains of polyd-l-alanine, terminating in short sequences of tyrosine and glutamic acid - GAT₁₀ an amino acid polymer of 60%l-glutamic acid, 30%l-alanine, and 10%l-tyrosine - GLA₅ an amino acid polymer of 57%l-glutamic acid, 38%l-lysine, and 5%l-alanine - DNP 2,4 dinitrophenyl - BGG bovine gamma globulin - FCS fetal calf serum - PWBC peripheral white blood cell - SWBC spleen white blood cell - T cell thymus-derived lymphocyte - B cell bone marrow-derived lymphocyte