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J Reich

Publications and source records attributed to J Reich.

At least 19 recordsLinked to original sources
PubMed2002

Is the unitarity of the quark-mixing CKM matrix violated in neutron beta-decay?

We report on a new measurement of neutron beta-decay asymmetry. From the result A(0) = -0.1189(7), we derive the ratio of the axial vector to the vector coupling constant lambda = g(A)/g(V) = -1.2739(19). When included in the world average for the neutron lifetime tau = 885.7(7) s, this gives the first element of the Cabibbo-Kobayashi-Maskawa (CKM) matrix V(ud). With this value and the Particle Data Group values for V(us) and V(ub), we find a deviation from the unitarity condition for the first row of the CKM matrix of Delta = 0.0083(28), which is 3.0 times the stated error.

Journal Article↗
PubMed2002

[Acute fatty liver in pregnancy: clinical and histopathological course. Case report].

Acute fatty liver of pregnancy is a rare disease which may be letal if diagnosis is missed. The pathogenesis is not completely clear, but there is some evidence that some cases have been associated with a genetic deficiency of fatty acid beta-oxidation. Other predisposing factors include primiparity, multiple pregnancy, male fetal sex and pre-eclampsia. Clinical presentation and laboratory findings are often unspecific. Increasing serum aminotransferases are characteristic in the early stage of the disease. Liver biopsy establishes the diagnosis and typically shows microvesicular, centrilobular fatty changes of hepatocytes. Differential diagnosis includes the HELLP-Syndrome, cholestasis of pregnancy, pre-eclampsia and viral or drug induced hepatitis. Without adequate treatment liver failure with coagulopathy and encephalopathy may develop. Two cases of acute fatty liver in pregnancy in an early stage are presented. Clinical and histopathological findings as well as diagnostic and therapeutic procedures are discussed.

Adult↗
PubMed2000

EST comparison indicates 38% of human mRNAs contain possible alternative splice forms.

Expressed sequence tag (EST) databases represent a large volume of information on expressed genes including tissue type, expression profile and exon structure. In this study we create an extensive data set of human alternative splicing. We report the analysis of 7867 non-redundant mRNAs, 3011 of which contained alternative splice forms (38% of all mRNAs analysed). From a total of 12572 ESTs 4560 different possible alternative splice forms were detected. Interestingly, 70% of the alternative splice forms correspond to exon deletion events with only 30% exonic insertions. We experimentally verified 19 different splice forms from 16 genes in a total subset of 20 studied; all of the respective genes are of medical relevance.

Alternative Splicing↗
PubMed2000

A pathway model of lipid metabolism to predict the effect of genetic variability on lipid levels.

Complex phenotypes such as serum lipid concentrations involve numerous genes and require the analysis of the combined effects of these gene products. We modeled the interactions of six key lipid metabolism genes by means of differential equations. We tested the model by inserting the effects of known mutations in the low-density lipoprotein receptor gene and the lipoprotein lipase gene, as well as the effects of a high-fat diet, and observed that the predictions corresponded very well to published measurements. Models such as the one that we present here will become indispensable for analyzing and understanding the effects of variation in multiple genes.

Carrier Proteins↗
PubMed2000

A rigid body model of the forearm.

In this article the forearm, with its complex, continuous motion of masses during pronation/supination, was approximated by a rigid body model consisting of a radial segment rotating around an ulnar segment. The method used to obtain the model parameters is based on three-dimensional voxel data that include velocity information. We propose a criterion that allows the voxels to be attributed to either of the two segments. It is based on the notion that the rotational kinetic energy determined from the voxel data equals the kinetic energy of the rigid body model. To obtain a three-dimensional smoothing we further propose a parameterization of the shape of both segments. These shapes can then be used to determine the dynamic integrals of the segments, i.e. mass, center of mass, and inertia. Using this approach we determined all model parameters for a human forearm from three series of MRI scans in a supinated, a pronated, and an intermediate position. In the appendix, a procedure is described that allows the dynamic quantities to be scaled homogeneously without recalculation of the integrals. Thus, this article provides all essential parameters required for three-dimensional dynamic simulations of general movements of the forearm.

Adult↗