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In this paper, the existence of two A-type cyclins in the mouse is demonstrated. In the adult mouse, the expression of cyclin A1, which has greatest sequence identity with Xenopus cyclin A1, is restricted to germ cells. In contrast cyclin A2, which has greatest sequence identity with human cyclin A and Xenopus cyclin A2, is expressed in all tissues analysed. In order to explore the function of cyclin A1 in germ cells, its expression during the meiotic cell cycle and its associated kinase subunits have been characterised in the testis. The levels of cyclin A1 mRNA rise dramatically in late pachytene spermatocytes and become undetectable soon after completion of the meiotic divisions; thus its expression is cell cycle regulated. In lysates of germ cells from adult testes, cyclin A1 is present in p13suc1 precipitates, and cyclin A1 immunoprecipitates possess histone H1 kinase activity. Three kinase partners of cyclin A1 were identified: p34cdc2, a polypeptide of 39 x 10(3) M(r) that is related to p33cdk2 and, in lesser quantities, p33cdk2. Cyclin A1 was also detected in oocytes; in metaphase I and metaphase II oocytes, a proportion of the cyclin A1 colocalises with the spindle, possibly suggestive of a functional interaction. These data indicate that mammalian germ cells contain cyclin A1-dependent kinases that either act as a substitute for, or in addition to, the cyclin A2-dependent kinases characterised in somatic tissues.

A 2641-bp EcoRI fragment of DNA that encodes the C-terminal part of the dihydrolipoyl acetyltransferase (E2) component and the dihydrolipoamide dehydrogenase (E3) component of the pyruvate dehydrogenase complex of Bacillus stearothermophilus has been cloned in Escherichia coli. Its nucleotide sequence was determined. A 705-bp truncated open reading frame was located at the 5'end of the insert which, together with the 588-bp truncated open reading frame at the 3' end of another EcoRI fragment of B. stearothermophilus DNA previously cloned and sequenced [Hawkins, C. F., Borges, A. & Perham, R. N. (1990) Eur. J. Biochem. 191, 337-446], was identified as the gene, pdhC, encoding the E2 polypeptide chain. Direct sequence analysis of the purified E2 chain confirmed that the two EcoRI fragments are adjoining in the B. stearothermophilus genome. The E3 gene, pdhD, begins just 4 bp downstream from the stop codon of the pdhC gene. The amino acid sequences deduced from the pdhC and pdhD genes correspond to proteins of 427 amino acids (E2, Mr 46,265) and 469 amino acids (E3, Mr 49,193), respectively. Both genes are preceded by potential ribosome-binding sites and the E3 gene is followed by a stemloop structure characteristic of rho-independent transcription terminators. The B. stearothermophilus E2 and E3 chains exhibit substantial sequence similarity with the corresponding subunits of other 2-oxo-acid dehydrogenase multienzyme complexes. The cloning and sequence analysis described here complete the description of the gene cluster (pdhA, B, C and D) which encodes the B. stearothermophilus pyruvate dehydrogenase multienzyme complex.

A 4175-bp EcoRI fragment of DNA that encodes the alpha and beta chains of the pyruvate dehydrogenase (lipoamide) component (E1) of the pyruvate dehydrogenase multienzyme complex of Bacillus stearothermophilus has been cloned in Escherichia coli. Its nucleotide sequence was determined. Open reading frames (pdhA, pdhB) corresponding to the E1 alpha subunit (368 amino acids, Mr 41,312, without the initiating methionine residue) and E1 beta subunit (324 amino acids, Mr 35,306, without the initiating methionine residue) were identified and confirmed with the aid of amino acid sequences determined directly from the purified polypeptide chains. The E1 beta gene begins just 3 bp downstream from the E1 alpha stop codon. It is followed, after a longer gap of 73 bp, by the start of another but incomplete open reading frame that, on the basis of its known amino acid sequence, encodes the dihydrolipoyl acetyltransferase (E2) component of the complex. All three genes are preceded by potential ribosome-binding sites and the gene cluster is located immediately downstream from a region of DNA showing numerous possible promoter sequences. The E1 alpha and E1 beta subunits of the B. stearothermophilus pyruvate dehydrogenase complex exhibit substantial sequence similarity with the E1 alpha and E1 beta subunits of pyruvate and branched-chain 2-oxo-acid dehydrogenase complexes from mammalian mitochondria and Pseudomonas putida. In particular, the E1 alpha chain contains the highly conserved sequence motif that has been found in all enzymes utilizing thiamin diphosphate as cofactor.

Physicians in Southeast Texas were surveyed to obtain information on attitudes and practices concerning generic drug substitution. Questionnaires were sent to all practicing primary care physicians in the area, and responses were received from about 36% of them. The investigation revealed that a large percentage of physicians did not readily permit substitution. Two major reasons given for not permitting substitution were concerns about therapeutic inequivalency and doubts about pharmacists' ability to substitute safely.

Eighty-four patients who had undergone different types of operation for duodenal ulcer have been studied by endoscopy and gastric biopsy. Half suffered from dyspepsia and vomiting but the other half had no symptoms and acted as controls. Endoscopic and histological abnormalities were found in both groups of patients. However, certain findings occurred more commonly in those with symptoms; severe and extensive hyperaemia, bile staining of the gastric mucus, and bile reflux seen on endoscopy were all significantly more common in those with symptoms than in those without. Active gastritis in the proximal stomach was also more common in those with symptoms. Gastritis of the stoma and antrum was found in 89% of all patients; as it was unconnected with symptoms it can be regarded as a "normal" finding. The incidences of contact bleeding, erosions, and oedema were not significantly different in the two groups.

Total and corrected (for albumin) serum calcium levels were investigated in a cross-sectional study of 394 patients with rheumatoid arthritis, 4490 healthy subjects, and 2609 inpatients at a district general hospital. Patients with rheumatoid arthritis had lower mean calcium levels than the healthy subject (p less than 0.001), but had similar levels to inpatients at the district general hospital. Thirty-eight inpatients with rheumatoid arthritis at a hospital for rheumatic diseases had lower mean corrected and total calcium levels than all other groups (p less than 0.01). Corrected or total calcium levels higher than 2.60 mmol/l or corrected calcium levels lower than 2.20 mmol/l were uncommon in the patients with rheumatoid arthritis. A longitudinal study of serum calcium levels in 17 patients with rheumatoid arthritis over 6-48 months showed considerable temporal variation in total and corrected calcium levels. Transient hypercalcaemia and hypocalcaemia occurred occasionally, but for most of the time calcium levels were normal. Changes in calcium levels were not related to changes in clinical, haematological, or immunological parameters of disease activity. Mean serum calcium levels are lower in disease than health; this occurs in RA as well as other diseases.

Infertility is a widespread problem among cattle herds in Jamaica and an intergovernmental project was initiated to investigate the problem. One aspect of the project included diagnosis of campylobacteriosis (vibriosis), which was suspected in some herds but had not been confirmed in the laboratory. Tests were undertaken in late 1978 using improved techniques for handling and transporting specimens to the laboratory. Campylobacter fetus subspecies fetus was isolated from five of six herds tested. The diagnosis of C. fetus infection has led to improvements in farm management and a better appreciation of more efficient artificial insemination and veterinary services.

The prognosis in rheumatoid arthritis respecting mortality was studied in a consecutive series of 489 hospital patients over a period of 18 years. The relative risk of mortality was raised in both men (2.6; p less than 0.001) and women (3.4; p less than 0.001). In the women the relative risk was also influenced by prior duration of RA and was characterised by a diminution in risk 5-9 years after first presentation. Relative risks for men were more uniformly distributed over time. Annual excess mortality rates were strongly associated with age at first presentation in women, the rate increasing with increasing age in both the group seen within 5 years of onset of disease (chi 2(1) for trend = 30.4; p less than 0.001) and in the later referral group (chi 2(1) = 34.0; p less than 0.001). A similar but much less marked effect was observed in men in the early referral group (chi 2(1) = 13.7; p less than 0.001) only. These results suggest that initially women may have a milder form of disease and that hormonal status may affect prognosis. Future long-term therapeutic studies in RA should take into account the prognostic factors of age, sex and duration of disease.

Joint inflammation in rheumatoid arthritis has been assessed, and the most useful guides to disease activity were determined by analysis of synovial fluid and blood together with the history of joint disability. The patient's own evaluation of the amount of pain suffered was the most useful clinical assessment. Differential cell count and glucose estimations were the most helpful guides in the synovial fluid, while C-reactive protein in the serum most accurately reflected disease activity. The effects of systemic steroids on these indices were studied, and the differences between seronegative and seropositive patients noted.

The reaction catalyzed by adenosine kinase purified from human erythrocytes proceeds via a classical ordered sequential mechanism in which adenosine is the first substrate to bind to and AMP is the last product to dissociate from the enzyme. However, the interpretation of the steady-state kinetic data is complicated by the finding that while AMP acts as a classical product inhibitor at concentrations greater than 5 mM, at lower concentrations AMP can act as an apparent activator of the enzyme under certain conditions. This apparent activation by AMP is proposed to be due to AMP allowing the enzyme mechanism to proceed via an alternative reaction pathway that avoids substrate inhibition by adenosine. Quantitative studies of the protection of the enzyme afforded by adenosine against both spontaneous and 5,5'-dithiobis(2-nitrobenzoic acid)-mediated oxidation of thiol groups yielded "protection" constants (equivalent to enzyme-adenosine dissociation constant) of 12.8 microM and 12.6 microM, respectively, values that are more than an order of magnitude greater than the dissociation constant (Kia = 0.53 microM) for the "catalytic" enzyme-adenosine complex. These results suggest that adenosine kinase has at least two adenosine binding sites, one at the catalytic center and another quite distinct site at which binding of adenosine protects the reactive thiol group(s). This "protection" site appears to be separate from the nucleoside triphosphate binding site, and it also appears to be the site that is responsible for the substrate inhibition caused by adenosine.

A consecutive series of 489 patients with rheumatoid arthritis seen at the centre was studied to determine their cancer morbidity. Overall the 36 cancers diagnosed in the series between 1964 and 1981 were not significantly in excess of the expected number, but there was a highly significant excess of tumours of the reticuloendothelial system. The excess was mainly due to 6 observed cases of lymphoma. We conclude that there is a highly significant association between rheumatoid arthritis and the subsequent development of lymphoproliferative malignancy in this series.

Two cross-sectional and one longitudinal study of patients with rheumatoid arthritis showed that platelet number correlated with both clinical and laboratory parameters of disease activity, including erythrocyte sedimentation rate, zeta sedimentation ratio, viscosity of plasma and blood, white cell count, liver enzymes, rheumatoid factor, and several acute-phase proteins. There was also an inverse relationship between platelet number and the haemoglobin and serum albumin levels. III Indium-labelled platelet survival was reduced in 4 patients with active rheumatoid arthritis despite a raised platelet count, with labelled platelets being localised to inflamed joints in the 2 patients studied. Platelet aggregation was normal. We suggest that the raised platelet count of active rheumatoid arthritis may be a useful index of disease activity and may represent a bone marrow stress (syndrome) response to shortened platelet survival, with platelet sequestration occurring in areas of synovial inflammation.

The ultrastructure of the synovial membrane has been studied in 6 patients with seronegative inflammatory arthropathies: Reiter's (2), Crohn's (2), Whipple's (1) and Behçet's disease (1). The most striking changes were found in the synovial B cells, many containing abnormally large mitochondria with altered cristae surrounded by fibrillar material. Similar material was present in dilated endoplasmic reticulum which was the probable source of groups of extracellular fibrillar spheroidal bodies. The B cells also contained electron dense granular lysosomes of very variable size which, in common with the abnormal mitochondria, were often associated with bundles of orientated microfilaments and large golgi complexes. Light microscopy of the synovial membrane was consistent with an inflammatory arthritis, as were the high white cell counts in the synovial fluid. Systemic activity in the patients was indicated by raised ESR and C-reactive protein (CRP).

Pulsed ultrasound was used to assess lateral pharyngeal wall (LPW) movement at the level of the velopharyngeal port in three adult males and two adult females. All subjects were normal talkers, and data were collected while each produced all combinations of the vowels /a/ and /i/ and consonants /p, t, k, s, m, n/ in a VCVCV context. On a qualitative basis, it appears that ultrasound technology has potential application for the measurement of LPW movement. However, a number of problems must be resolved before ultrasonic techniques surpass current methods of studying velopharyngeal function and/or incompetence.

Simultaneous plasma and synovial fluid samples have been obtained from patients, having reached a steady state on phenylbutazone, as a means of investigating factors influencing drug penetration into synovial fluid. Synovial fluid levels are lower than, but related to, plasma levels and are higher in rheumatoid disease (55-100% plasma levels) than in osteoarthritis (less than 50%). Patients with a more active form of the disease have higher synovial fluid drug concentrations. Results are discussed in the light of present knowledge and areas for further study are proposed.

Seven cases of diffuse interstitial lung disease (DILD) are reported with an unequivocal temporal relationship between the development of the lung disease and treatment with gold (6 cases) and penicillamine (1 case). They were characterised clinically by the sudden onset of dyspnoea and crepitations and radiologically by diffuse bilateral pulmonary shadowing. Most showed evidence of hypersensitivity such as eosinophilia, a raised serum IgE level in response to gold, proteinuria, thrombocytopenia, or an immediate postinjection reaction. DILD is a serious complication of treatment with gold and penicillamine that is commoner than generally realised.

The disruption of a kidney cortex microsomal membrane preparation by a binary, nonionic detergent, was followed by using as markers, the changes in total protein content, and (Na+, K+)-ATPase in a supernatant fraction. Both markers responded similarly to changes in pH, microsome concentration and detergent concentration, but responded differently for time-dependent studies. The (Na+, K+)-ATPase activity was increased 2.2-fold (76.1 mumoles Pi/mg protein/h, 95% ouabain-sensitive) by a single detergent treatment and 3.5-fold (92% ouabain-sensitive) by a sequential detergent treatment. Changes in the critical micelle concentration (cmc) were observed for varying detergent and protein concentrations, which suggest interactions of monomeric detergent with the membrane. The peak of (Na+, K+)-ATPase activity occurred above the cmc which suggests the participation of micelles in releasing the enzyme from the membranes. Hill plots of the protein released as the detergent concentration was varied showed a change in the slope near the cmc indicating a four-fold increase in the binding of detergent to membranes as the detergent concentration is increased above the cmc. These results suggest that the disruption of membranes by detergent involves the binding of detergent monomers to the membrane followed by the formation of co-micelles of the detergent with segments of the membrane to complete the separation process.

A series of 20 patients with definite or classical rheumatoid arthritis who subsequently developed a lymphoproliferative malignancy are described. The mean time between the onset of the 2 diseases was 13.2 years. A wide range of types of non-Hodgkin's lymphoma and Hodgkin's disease were found; there were no unusual histological features in the lymphomas. Although many of the patients had had gold, penicillamine, and other second-line drugs, none of them had received cytotoxic drugs, and there was no evidence that therapy was a cause of their malignancies. The likely cause of the association is a predisposition to both diseases.

The amino acid sequences of a wide range of enzymes that utilize thiamin pyrophosphate (TPP) as cofactor have been compared. A common sequence motif approximately 30 residues in length was detected, beginning with the highly conserved sequence -GDG- and concluding with the highly conserved sequence -NN-. Secondary structure predictions suggest that the motif may adopt a beta alpha beta fold. The same motif was recognised in the primary structure of a protein deduced from the DNA sequence of a hitherto unassigned open reading frame of Rhodobacter capsulata. This putative protein exhibits additional homology with some but not all of the TPP-binding enzymes.

Rod-shaped organisms identical to those present in the jejunal mucosa have been found in the synovial membrane of a patient with Whipple's disease. These probably caused inflammatory changes which sere reflected in an increase of the cellular content and high enzyme levels (acid phosphatase and 5-nucleotidase) of the synovial fluid. Tetracycline was effective in controlling the bowel lesion but only had a temporary effect upon the arthritis. Erythromycin controlled both the bowel lesion and the arthritis.

A series of 489 consecutive patients with definite or classical rheumatoid arthritis was followed for a mean of 11.2 years. Cohort-analysis of the series showed a three-fold increase in mortality overall in comparison with age- and sex-specific rates in the general population. In patients first seen in hospital early in the course of the disease (less than 5 years from onset), the excess of deaths from circulatory, respiratory and musculoskeletal disorders was highly significant. Malignant disease and digestive system disorders accounted for a small excess of borderline significance. Patients who were referred later (greater than 5 years from onset) experienced, in addition, a highly significant excess of deaths from infections and disorders of the digestive and genito-urinary system but not from malignant neoplasms.

Following the first diagnosis of campylobacteriosis in Jamaican cattle a field study was undertaken to determine the pathogenicity of Campylobacter fetus subspecies venerealis Jam (Jamaican strain) and to evaluate the effectiveness of vaccination in controlling the disease. A total of 46 nonpregnant yearling heifers and four two-year-old bulls were used in two separate experiments. The results showed that C fetus subspecies venerealis Jam readily colonised the reproductive tract of susceptible heifers and persisted in some animals (68 per cent of unvaccinated and 33 per cent of vaccinated animals) for the duration of the experiment. Pregnancy was confirmed in 13 of 18 (72 per cent) culture-negative heifers but in only eight of 28 (29 per cent) of the heifers with two or more positive cultures. Vaccination appeared to be curative because 44 per cent of vaccinated heifers were cleared of infection whereas 85 per cent of unvaccinated, inoculated heifers remained infected for at least 17 weeks. Vaccination improved the fertility level of the infected heifers threefold. Infection was not established in vaccinated bulls used for breeding infected heifers.

The effect of cimetidine on the risk of further bleeding shortly after acute gastrointestinal haemorrhage from peptic ulcer was investigated in a double-blind randomised trial. 34 patients were given cimetidine and 32 placebo, the two groups being matched for age, sex, and severity of haemorrhage. Further bleeding within a week of admission was detected clinically in 8 patients on cimetidine and 15 on placebo. Cimetidine had no effect on bleeding from duodenal ulcer, but only 2 of 14 patients with gastric ulcer treated with cimetidine bled again, compared with 10 of 19 patients on placebo. Cimetidine, therefore, may help to prevent haemorrhage from gastric ulcer but not duodenal ulcer.