The sequence of the gene for cytochrome c oxidase subunit I, a frameshift containing gene for cytochrome c oxidase subunit II and seven unassigned reading frames in Trypanosoma brucei mitochrondrial maxi-circle DNA.

A 9.2 kb segment of the maxi-circle of Trypanosoma brucei mitochondrial DNA contains the genes for cytochrome c oxidase subunits I and II (coxI and coxII) and seven Unassigned Reading Frames ("URFs"). The genes for coxI and coxII display considerable homology at the aminoacid level (38 and 25%, respectively) to the corresponding genes in fungal and mammalian mtDNA, the only striking point of divergence being an unusually high cysteine content (about 4.5%). The reading frame coding for cytochrome c oxidase subunit II is discontinuous: the C-terminal portion of about 40 aminoacids, is present in the DNA-sequence in a -1 reading frame with respect to the N-terminal moiety. URF5, 8 and 10, show a low but distinct homology (about 20%) to mammalian mitochondrial URF-1, 4 and 5, respectively. In URF5, the first AUG is found at codon 145, whereas extensive homology to mammalian URF-1 sequences occurs upstream of this position. The possibility exists that UUG can serve as an initiator codon. URF7 and URF9 have a highly unusual aminoacid composition and do not possess AUG or UUG initiator codons. These URFs probably do not have a protein-coding function. The segment does not contain conventional tRNA genes.     

Assignment of the gene for uroporphyrinogen decarboxylase to human chromosome 1 by somatic cell hybridization and specific enzyme immunoassay

Summary A specific enzyme immunoassay of uroporphyrinogen decarboxylase was developed and applied to the detection of the human enzyme in man-rodent somatic cell hybrids. This method allowed to assign the gene for uroporphyrinogen decarboxylase to human chromosome 1.     

Chromosome studies in 496 infertile males with a sperm count below 10 million/ml

Summary Chromosome studies were performed on 106 men with azoospermia and 390 men with oligozoospermia (consistant sperm count below 10 million/ml). Constitutional chromosome abnormalities were found in 14.1% of the azoospermia group and in 5.1% of the oligozoospermia group. An overall incidence of 7.1% constitutional abnormalities indicates that this criterion of selection may be advisable for routine chromosome analysis of infertile men. A reduction of 25% in the workload increases the yield of chromosome abnormalities in the group of infertile men to 10–14 times above that expected in the normal population.     

Effect of the Compound CGA 78039 and Streptomycin on the Expression of Bacterial Stem Rot in Dieffenbachia

Bacterial stem rot, due to Erwinia chrysanthemi , is a serious problem in ornamental crop protection, e.g. in Dieffenbachia . It was our aim to compare the effect of the synthetic compound CGA 78039 and streptomycin sulphate on the suppression of stem rot disease in Dieffenbachia . Different treatments were applied under natural and artificial infection pressures. Pretreatment of the mother plants with CGA 78039, followed by dipping of the cuttings overnight in the same solution before potting and five subsequent weekly foliar sprays during growth reduced the expression of stem rot in Dieffenbachia significantly.     

Peptide YY (PYY) immunoreactivity is co-stored with glucagon-related immunoreactants in endocrine cells of the gut and pancreas

Summary In this study we report the localisation of PYY immunoreactivity in intestinal mucosa endocrine (EG) cells containing glucagon-related peptides and also in foetal pancreatic A cells of rat and man. Radioimmunoassay of human foetal pancreatic extracts revealed the presence of PYY immunoreactivity, the concentration of which declined with age (from 65.42 pmol/g at week 20 to 17.0 pmol at week 40; correlation coefficient=–0.893), in contrast to the amount of glucagon which remained statistically constant throughout the same foctal period. The identity of this PYY immunoreactive material with the original 36 amino acid porcine peptide has been shown by high pressure liquid chromatography (HPLC).     

Induction of ovulation with pulsatile luteinising hormone releasing hormone.

Ovulation was successfully induced with luteinising hormone releasing hormone in 28 women with hypothalamic amenorrhoea who had failed to respond to treatment with clomiphene. Luteinising hormone releasing hormone was administered in a pulsatile manner with miniaturised automatic infusion systems. The rate of ovarian follicular maturation, as monitored by serial pelvic ultrasonography, was similar to that observed in spontaneous cycles. Endocrine assessment by serial measurement of gonadotrophin, oestradiol, and progesterone concentrations showed hormone concentrations to be within the normal range. Intravenous treatment was required in only two patients, the remainder responding satisfactorily to subcutaneous infusion. All patients conceived within six cycles of treatment, and only one multiple pregnancy occurred.     

The fate of bilirubin-IXalpha glucuronide in cholestasis and during storage in vitro. Intramolecular rearrangement to positional isomers of glucuronic acid.

1. In aqueous solution above pH7 bilirubin-IXalpha 1-O-acylglucuronide rapidly isomerizes to the non-C-1 glucuronides by sequential migration of the bilirubin acyl group from position 1 to positions 2, 3 and 4 of the sugar moiety. The transformations are enhanced by increasing the pH. Compared with the rates at 37 degrees C the transformations are rather slow at 0 degrees C. Virtually complete inhibition is observed at values below pH6. The isomerization at 25 degrees C and pH 7.4 is not affected by the presence in the solutions of a molar excess of human serum albumin. 2. Isomerization in bile kept at 37 degrees C at pH7.7-7.8 is probably non-enzymic, as the rates of change are similar to those observed under comparable conditions for aqueous solutions of glucuronides of bilirubin-1Xalpha and of azodipyrrole. 3. Analysis without delay of normal biles of man and rats collected at 0 degrees C over a maximum period of 10 min shows that the bilirubin-IXalpha mono- and di-glucuronides consist exclusively of the 1-O-acyl isomers. 4. The mixtures of the four positional isomers of bilirubin-IXalpha glucuronide found in freshly collected biles of man and rats with cholestasis probably originate from initially synthesized 1-O-acylglucuronide by the same mechanism of sequential migration as has been observed in aqueous solutions of conjugated bilirubin-IXalpha.     

Mechanisms of replenishment of nuclear and rogen receptor in rat ventral prostate

1. The concentration of androgen receptor in the nucleus of the prostatic cell is rapidly elevated by the administration in vivo of 2μg of [³H]testosterone to 1-day-castrated rats. From a concentration of 2300 receptors/nucleus at 5min after intravenous injection of hormone, there is an increase to 21000 receptors/nucleus at 60min. At the same time, the amount of binding of androgen in the cytoplasm remains constant at a relatively low value. 2. An identical dose of [³H]testosterone administered to 7-day-castrated rats produces a much smaller change in the concentration of nuclear receptor, from 700 receptors/nucleus at 5min to only 4300 receptors/nucleus at 60min. Thus the reservoir from which nuclear receptor is replenished is considerably smaller in regressed prostatic cells. Again, the amount of binding of androgen in the cytoplasm remains unchanged at a low value over the experimental time course of 60min. 3. In contrast with the scant labelling of cytoplasmic receptor achieved by injecting animals with [³H]testosterone, labelling in vitro, by incubation of tissue slices with radioisotope, indicates that prostate of 1-day-castrated animals actually contains 21400 receptors/cell in the cytoplasmic compartment, and prostate of 7-day-castrated animals 3000 receptors/cell. 4. Owing to the similarity between the concentration of nuclear receptor measured in vivo and the concentration of cytoplasmic receptor measured in vitro, the labelling techniques in vivo and in vitro were used in sequence to demonstrate the movement of most of the cytoplasmic receptor into the nucleus. In the 5–60min interval after the administration of [³H]testosterone to 1-day-castrated rats, a decrease of 17400 receptor molecules in the cytoplasm is exactly mirrored by an increase of 17200 receptor molecules in the nucleus. 5. These results imply that, in prostate of 1-day-castrated rats, nuclear receptor is replenished exclusively by translocation of cytoplasmic receptor. However, in the regressed prostate of 7-day-castrated rats, only about 25% of the nuclear receptor is replenished through translocation of existing cytoplasmic receptor. The remainder is ultimately synthesized during new rounds of cell division induced by hormone.     

Glucuronic acid conjugates of bilirubin-IXα in normal bile compared with post-obstructive bile. Transformation of the 1-O-acylglucuronide into 2-, 3-, and 4-O-acylglucuronides

Structures have been determined for bilirubin-IXalpha conjugates in freshly collected bile of normal rats, dogs and man and in post-obstructive bile of man and rats. The originally secreted conjugate has been characterized as azopigment (I), i.e. a 1-O-acyl-beta-d-glucopyranuronic acid glycoside. Conversion of the acetylated methyl ester of azopigment (I) into methyl 2,3,4-tri-O-acetyl-1-bromo-1-deoxy-beta-d-glucopyranuronate (V) indicates the pyranose ring structure for the carbohydrate and a C-1 attachment for the bilirubin-IXalpha acyl group. Alternative procedures for deconjugation of azopigment (I) and its derivatives are also described. In post-obstructive bile, the 1-O-acylglucuronide is converted into 2-, 3- and 4-O-acylglucuronides via sequential intramolecular migrations of the bilirubin acyl group. The following approach was utilized. (1) The tetrapyrrole conjugates were cleaved to dipyrrolic aniline and ethyl anthranilate azopigments, and the azopigments were separated as the acids or methyl esters. (2) The isomeric methyl esters were characterized by mass spectral analysis of the acetates and silyl ethers. (3) The free glycosidic function was demonstrated by 1-oxime and 1-methoxime derivative formation. (4) The position of the dipyrrolic O-acyl group was determined for the methyl esters by protecting the free hydroxyl groups of the glucuronic acid moieties as the acetals formed with ethyl vinyl ether and by further conversion of the carbohydrates into partially methylated alditol acetates. These were analysed by using g.l.c.-mass spectrometry. The relevance of the present results with regard to previous reports on disaccharidic conjugates is discussed. Details of procedures for the formation of chemical derivatives for g.l.c. and mass spectrometry have been deposited as Supplementary Publication SUP 50081 (15 pages) at the British Library Lending Division, Boston Spa, West Yorkshire LS23 7BQ, U.K., from whom copies can be obtained on the terms indicated in Biochem. J. (1978), 169, 5.