Estimating genetic and non-genetic components of variance for fasting glucose levels in pedigrees ascertained through non-insulin dependent diabetes

Fasting glucose levels measured on 337 individuals in 14 pedigrees ascertained through a proband with non-inuslin dependent diabetes were used to estimate genetic and non-genetic components of variance under a multifactorial model of inheritance. In this sample genetic factors were important in controlling variation in basal carbohydrate metabolism, as represented by age-adjusted log-fasting glucose. There was no evidence that arbitrary sib common environments or arbitrary parent common environments accounted for significant portions of the variability in fasting glucose in these data. An arbitrary environment shared by parent and offspring, however, had a marginally significant impact on the likelihood. Parameter estimates obtained from multifactorial models analysed in this manner are sensitive to extreme phenotypic values, however, and caution must be exerciese in estimating total genetic variation. While additive genetic factors did account for a significant proportion of the total variation in fasting glucose, a large proportion remained unexplained.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66167/1/j.1469-1809.1982.tb01586.x.pd

The definition of chemical diabetes

The natural history of diabetes mellitus can be arbitrarily divided into four stages based on the presence or absence of abnormal carbohydrate metabolism. Overt diabetes is the most advanced stage, characterized by elevated fasting blood glucose concentration and classical symptoms. This stage is divided into ketotic and nonketotic forms. Preceding overt diabetes is the latent or chemical diabetic stage, with no symptoms of diabetes but demonstrable abnormality of oral or intravenous glucose tolerance. Subclinical diabetes is an earlier stage when glucose tolerance is abnormal only with stress, such as pregnancy or the administration of cortisone. The earliest stage, prediabetes, extends from conception until the first demonstrable abnormality in glucose tolerance. In groups of presumed prediabetic individuals, delayed and/or decreased plasma insulin response to glucose has been noted. Progression of the diabetes may not occur, may occur very slowly or very rapidly, and regression to an earlier stage of abnormality may also occur.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/33955/1/0000225.pd

Treatment of chemical diabetes mellitus with sulfonylurea compounds

Abnormality in glucose tolerance appears to correlate with arteriosclerotic disease, even when the abnormality is quite mild. Though there is no evidence for prevention of these vascular problems by correction of the carbohydrate abnormality, it seems reasonable to attempt such a correction in an investigational setting. We have used sulfonylurea (tolbutamide, chlorpropamide) in children and young adults (9-35 yr) without obesity, who have chemical diabetes. No apparent effect on insulin output has been noted, even with normalization of glucose tolerance.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/33962/1/0000232.pd

Using stochastic acceleration to place experimental limits on the charge of antihydrogen

Assuming hydrogen is charge neutral, CPT invariance demands that antihydrogen also be charge neutral. Quantum anomaly cancellation also demands that antihydrogen be charge neutral. Standard techniques based on measurements of macroscopic quantities of atoms cannot be used to measure the charge of antihydrogen. In this paper, we describe how the application of randomly oscillating electric fields to a sample of trapped antihydrogen atoms, a form of stochastic acceleration, can be used to place experimental limits on this charge

METABOLIC STUDIES OF CHLORPROPAMIDE IN NORMAL MEN AND IN DIABETIC SUBJECTS

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72472/1/j.1749-6632.1959.tb39585.x.pd

Production of antihydrogen at reduced magnetic field for anti-atom trapping

We have demonstrated production of antihydrogen in a 1$,$T solenoidal magnetic field. This field strength is significantly smaller than that used in the first generation experiments ATHENA (3$,$T) and ATRAP (5$,$T). The motivation for using a smaller magnetic field is to facilitate trapping of antihydrogen atoms in a neutral atom trap surrounding the production region. We report the results of measurements with the ALPHA (Antihydrogen Laser PHysics Apparatus) device, which can capture and cool antiprotons at 3$,$T, and then mix the antiprotons with positrons at 1$,$T. We infer antihydrogen production from the time structure of antiproton annihilations during mixing, using mixing with heated positrons as the null experiment, as demonstrated in ATHENA. Implications for antihydrogen trapping are discussed

Search For Trapped Antihydrogen

We present the results of an experiment to search for trapped antihydrogen atoms with the ALPHA antihydrogen trap at the CERN Antiproton Decelerator. Sensitive diagnostics of the temperatures, sizes, and densities of the trapped antiproton and positron plasmas have been developed, which in turn permitted development of techniques to precisely and reproducibly control the initial experimental parameters. The use of a position-sensitive annihilation vertex detector, together with the capability of controllably quenching the superconducting magnetic minimum trap, enabled us to carry out a high-sensitivity and low-background search for trapped synthesised antihydrogen atoms. We aim to identify the annihilations of antihydrogen atoms held for at least 130 ms in the trap before being released over ~30 ms. After a three-week experimental run in 2009 involving mixing of 10^7 antiprotons with 1.3 10^9 positrons to produce 6 10^5 antihydrogen atoms, we have identified six antiproton annihilation events that are consistent with the release of trapped antihydrogen. The cosmic ray background, estimated to contribute 0.14 counts, is incompatible with this observation at a significance of 5.6 sigma. Extensive simulations predict that an alternative source of annihilations, the escape of mirror-trapped antiprotons, is highly unlikely, though this possibility has not yet been ruled out experimentally.Comment: 12 pages, 7 figure