New Short-Lived Isotope

Two short-lived isotopes ^{221}U and ^{222}U were produced as evaporation residues in the fusion reaction ^{50}Ti+^{176}Yb at the gas-filled recoil separator TASCA. An α decay with an energy of E_{α}=9.31(5) MeV and half-life T_{1/2}=4.7(7) µs was attributed to ^{222}U. The new isotope ^{221}U was identified in α-decay chains starting with E_{α}=9.71(5) MeV and T_{1/2}=0.66(14) µs leading to known daughters. Synthesis and detection of these unstable heavy nuclei and their descendants were achieved thanks to a fast data readout system. The evolution of the N=126 shell closure and its influence on the stability of uranium isotopes are discussed within the framework of α-decay reduced width.

The N-terminal amino acid sequence from alpha 1-antitrypsin isolated from liver inclusion bodies.

The alpha 1-antitrypsin from the liver of a subject with alpha i-antitrypsin deficiency was purified and subjected to automated Edman degradation. The N-terminal amino acid sequence from position 1 to 12 was identical to that in plasma alpha 1-antitrypsin, type Z. This result precludes that the intrahepatic accumulation of Z alpha 1-antitrypsin is due to a defective removal of a signal peptide.

Preparation of monoiodotyrosine-13-glucagon.

Glucagon was iodinated with the lactoperoxidase method at pH 10.0 in the presence of propylene glycol using a substitution of 0.3 g-atom I/mol glucagon. Under these conditions the reactivity of the iodine to tyrosine at position 13 is found to be 4-fold that of the tyrosine at position 10. The amount of diiodotyrosine was less than one-twentieth that of the monoiodotyrosine at either tyrosine residue. Relatively pure monoiodo[125I]tyrosine-13-glucagon can be separated from other iodoglucagons by means of DEAE-chromatography. Such a homogeneous preparation with a known position of the iodine makes it possible to study a specific interaction between the monoiodoglucagon and the glucagon antisera or the glucagon receptor.

The reactive site of alpha 1-antitrypsin is C-terminal, not N-terminal.

alpha 1-Antitrypsin recovered from trypsin-alpha 1-antitrypsin complexes was shown to be a mixture of two peptides which remained associated in 6 M guanidine and in 1% acetic acid, but were separated by SDS-polyacrylamide gel electrophoresis. The larger peptide had an Mr of 47 000 and gave low yields on end-group analysis; the smaller had an Mr of 4000 and was the C-terminal 36-residue fragment of alpha 1-antitrypsin. These results explain the consistent but erroneous finding of a reactive site near the N-terminus of alpha 1-antitrypsin, and confirm that the reactive site is 36 residues from the C-terminus.

Capillary blood on filter paper for determination of HbA1c by ion exchange chromatography.

OBJECTIVE: To facilitate HbA1c determination, we evaluated an HbA1c filter paper system enabling capillary blood sampling at home by the patients. RESEARCH DESIGN AND METHODS: Capillary blood (two drops) was applied to a filter paper (HbA1c Via Post) and sent to the laboratory where a small disc was punched out on the filter paper. Hemoglobin was eluted from the disc in a buffer containing cysteine to eliminate the interfering glutathione adduct (HbA3) formed during storage. Analysis was performed by ion-exchange chromatography (Mono S, high-performance liquid chromatography), and the eluate was compared with hemolysate of venous blood from 41 patients. The stability of blood impregnated on filter paper was checked at different temperatures over different periods of time. RESULTS: There was an excellent agreement (r = 0.99) between HbA1c values from capillary blood on filter paper and HbA1c values from venous blood. HbA1c values were constant when stored on filter paper for 5-7 days at 20-21 degrees C (room temperature) or at 4-6 degrees C (refrigerator) for 10 days as well as at -70 degrees C for several months after blood sampling. A new chromatographic-interfering hemoglobin fraction both from venous and capillary samples was identified as free alpha-chain of hemoglobin. CONCLUSIONS: The HbA1c filter paper system enables capillary blood sampling at home, eliminates the need of vein puncture in children and adults, and provides the diabetologist with an HbA1c value when the patient visits the clinic without a need for a previsit phlebotomy.

The amino acid substitutions of human alpha 1-antitrypsin M3, X and Z.

alpha 1-Antitrypsin has been isolated from individuals with inherited genetic variants M3, X and Z. A fragmentation and peptide mapping system is described which together with amino acid and sequence analyses revealed the substitutions in M3 at 376 of Glu to Asp, in X at 204 of Glu to Lys and in the physiologically innocent Z a mutation at 213 of Val to Ala. The latter represents a second amino acid substitution in the Z protein.

Amino acid sequence of the predominant basic protein in human seminal plasma.

The predominant basic protein in liquefied human seminal plasma is the major degradation product of the gel-forming protein secreted by the seminal vesicles. The amino acid sequence of this basic protein is presented. The basic protein contains 52 amino acid residues. It is devoid of cysteine, methionine, tryptophan, and leucine, but contains seven histidine residues located in the NH2-terminal half of the molecule. The calculated Mr of 5753 is in close agreement with that obtained from gel filtration in guanidine-HCl on Sephacryl S-200 (Mr = 6000).

Assessment of sex hormones and bone mineral density in relation to occurrence of fracture in men: a prospective population-based study.

Patients with fragility fractures have low bone mineral density (BMD)--this statement is supported mainly by data on women. In this study, including only men, the objectives were to determine whether a decline in BMD alone or in combination with data on male sex hormones and skinfold thickness could be of value in predicting forthcoming fractures. We also wanted to find out whether high consumers of alcohol can be identified by measuring BMDs and male sex hormones. A prospective, population-based study was performed in the city of Malmö, Sweden. 242 men were randomly selected; all were of Scandinavian ethnic background, and were aged 50, 60, 70, and 80 years. Forearm BMD, testosterone, sex-hormone-binding globulin (SHBG), and skinfold thickness were analyzed. In addition, alcohol consumption and carbohydrate-deficient transferrin (CDT)--a marker of alcohol abuse--were analyzed. The study group was followed prospectively for 7 years and all fractures sustained were recorded. Prospectively, for a 1 SD decrease in forearm BMD, the Cox proportional hazard model gave a relative risk (RR) of 1.75 with a 95% confidence interval of 1.08-2.83 for a forthcoming fracture and 3.88 (1.30-11.57) for a hip fracture. For a 1 SD change in skinfold thickness, measured on the dorsum of the hand, a RR of 1.69 (0.99-2.87) for a forthcoming fracture was found and the corresponding value for hip fracture was 2.34 (1.10-5.00). Testosterone and SHBG did not enhance fracture prediction. Abusers of alcohol had, retrospectively, significantly more fractures. Individuals with alcohol consumption rates in the highest quartile had significantly higher CDT levels, but we were unable to identify high consumers of alcohol by analyzing BMD or sex hormones. In this study we found that forearm BMD and skinfold thickness could be used in predicting forthcoming fractures in men.

Plasma prealbumin concentration in alpha 1-antitrypsin deficiency (PiZ).

The concentrations of 7 plasma proteins including prealbumin, retinol-binding protein, and alpha 1-antitrypsin were measured by electroimmunoassay in plasma from 19 persons with alpha 1-antitrypsin deficiency PiZ, 20 persons with phenotype PiMZ, and 26 healthy men with normal alpha 1-antitrypsin content. The prealbumin concentrations in the PiZ individuals were slightly lower than in the other groups. Only one individual in the PiZ group showed very low levels of prealbumin and retinol-bonding protein. Thus contrary to what has been proposed earlier our results show that severe prealbumin deficiency is not a common finding in alpha 1-antitrypsin deficiency PiZ.

Clinical utility of serum fructosamine in diabetes mellitus compared with hemoglobin A1c.

To evaluate the clinical utility of fructosamine as a mean of monitor glycaemic control, fructosamine and HbA1c were compared in 46 random out-patients visiting a Diabetic Clinic as well as in 25 inpatients admitted to a Diabetes Day Care Unit. In the out-patients, there were a significant correlations between fructosamine and fasting blood glucose (r = 0.75) as well as between fructosamine and HbA1c (r = 0.91). However, when the reference values were considered, interesting differences were found; only 4% of the out-patients showed normal HbA1c values while 39% showed normal fructosamine values. Accordingly, fructosamine and HbA1c evaluate different aspects of glycaemic control. During an admission of 7 days to the Diabetes Day Care Unit no statistical changes in mean blood glucose and fructosamine values occurred. On the other hand, two weeks after discharge from the Unit, not only fructosamine (3.58 +/- 0.16 mmol vs 3.09 +/- 0.08 mmol/l) but also HbA1c (9.52 +/- 0.38% vs 8.33 +/- 0.23%) had improved significantly. Thus HbA1c measures improvements in glycaemic control as early as 3 weeks after changes in treatment. At six weeks after discharge HbA1c (7.63 +/- 0.34%) but not fructosamine (3.02 + 0.14 mmol/l) had improved further. HbA1c is a reliable marker of glycaemic control while the value of fructosamine in clinical practice is unclear.

Immediate assessment of HbA1c under field conditions in Tanzania.

In Tanzania, assessment of blood glucose is the most frequently used method for evaluating glycaemic control in diabetic patients. The patients' metabolic control is often poor and the determination of glycated haemoglobin (HbA1c) for long-term control could be a valuable tool to better manage the treatment. The aim of this study was to determine whether an immediate assessment method for HbA1c (DCA 2000 analyzer) gives reliable results in the warm and moist climate of east Africa. The study was performed in two parts. One equipment test in Sweden where blood samples from 65 diabetic patients were analysed in a DCA 2000 kept at room temperature and in another kept in a climate chamber. The samples were also analysed with HPLC as a reference method. In the second part HbA1c was analysed in 159 Tanzanian diabetic patients with a DCA 2000 and with HPLC combined with a filter paper technique (HbA1c via Post). The study showed that the DCA 2000 gives reliable results at 85% humidity and a temperature not exceeding +31 degrees C. The correlation with the HPLC analysis varied between 0.94 and 0.98. The conclusion is that the DCA 2000 analyzer can be used in Tanzania during the winter but has to be placed in an air-conditioned room if the temperature exceeds +31 degrees C.

Improved method for analysis of glycated haemoglobin by ion exchange chromatography.

The Pharmacia Mono S column for glycated haemoglobin (HbA1c) was compared with Mono S HR 5/5 and three other cation exchange columns to optimize analysis of HbA1c. This column allows a significant decrease in separation time, resulting in a sample throughput of 12 samples per hour. The choice of parameters for integration of peak areas in the chromatograms is very important for reproducible results. Since pure calibrators of HbA1c are not available, the relative contribution of HbA1c to the total amount of haemoglobin is calculated. We have compared valley-to-valley integration with baseline integration to assess reproducibility. Valley-to-valley integration significantly enhances the reproducibility of the method and is therefore preferable for routine analyses of HbA1c.

[Capillary electrophoresis: principles and practice in clinical laboratory]. / L'électrophorèse capillaire: principe et applications au laboratoire de biologie clinique.

Capillary electrophoresis represents a relatively new analytical technique. This methodology has diversified and given rise to various modes such as capillary zone electrophoresis, capillary gel electrophoresis, micellar electrokinetic capillary chromatography, capillary isoelectric focusing and capillary isotachophoresis. If capillary electrophoresis was first introduced in research laboratories, this technique is now making an entrance to the clinical laboratory. This is due to its rapid and high-efficiency separation power, its potential applications and its possible automation. Thus, capillary electrophoresis represents an attractive alternative to some time-consuming techniques. Thanks to its versatility, the use of capillary electrophoresis has been proposed for the separation and quantification of a wide spectrum of biological components ranging from macromolecules (proteins, lipoproteins, nucleic acids) to small analytes (amino acids, organic acids or drugs). This paper illustrates the potential of capillary electrophoresis which should rapidly become a major technology for a modern clinical laboratory.

[Drunken driver examinations. CD-transferrin is a valuable marker of alcohol consumption]. / Undersökningar vid en körkortsmottagning. CD-transferrin värdefull markör på alkoholkonsumtion.

The article reports findings in a study of 198 subjects attending a psychiatric out-patient clinic, with known or suspected high alcohol consumption during a 12-month period, about half of whom had had their driving licences revoked. The level of carbohydrate-deficient transferrin (CDT) was found to be a valuable marker of alcohol consumption, and a useful adjunct to the measurement of liver enzymes. Both GGT (gamma-glutamyltransferase) and CDT levels were significantly higher in high alcohol consumers than in low consumers. Alcohol the two markers did not differ from each other in statistical significance, CDT was associated with greater sensitivity and specificity; the sensitivity of CDT was 69% for men and 79% for women, as compared with 62% and 40%, respectively, for GGT; the specificity of CDT was 81% for men and 100% for women, as compared with 82% and 72%, respectively, for GGT. Together, GGT and CDT detected 91% of the male and 93% of the female high consumers. Among younger men, CDT values were higher in the subgroup with a history of traffic offences than in the subgroup without such a history, thus suggesting that CDT levels may be increased by heavy weekend beer consumption. A few cases of false-positive CDT results were found to be attributable to genetic anomalies of the transferrin molecule. Cases characterised by disparity between the CDT level and the clinical picture require further, more specific, analysis. Used in combination with GGT, CDT is thus a feasible marker for use in monitoring alcohol consumption in drivers needing to qualify for the restoration of their licences.

[CDT a valuable marker of overconsumption of alcohol. Guidelines for its use in connection with automobile driver examination]. / CDT värdefull markör för överkonsumtion av alkohol. Riktlinjer för dess användning vid körkortsprövning.

According to the medical regulations for obtaining a driver's license in Sweden, alcohol abuse/dependency constitutes sufficient grounds for denial. In the case of a conviction for gross drunk driving, it is incumbent upon the offender to present a medical certificate verifying a "sober lifestyle". Biological markers are important tools for proving alcohol abuse in each of these contexts. In this connection, CDT analyses play a key role through their high marked specificity for increased alcohol consumption. The authors have agreed upon the guidelines as presented in this paper for determining sobriety as it pertains to possession of a driver's license. Special emphasis is placed on how CDT tests should be used and interpreted in such contexts, as well as their value as evidence in the case of increased CDT levels.