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B Adams

Publications and source records attributed to B Adams.

At least 73 records · Page 4Linked to original sources
PubMed1992

The promoter of the CD19 gene is a target for the B-cell-specific transcription factor BSAP.

The CD19 protein is expressed on the surface of all B-lymphoid cells with the exception of terminally differentiated plasma cells and has been implicated as a signal-transducing receptor in the control of proliferation and differentiation. Here we demonstrate complete correlation between the expression pattern of the CD19 gene and the B-cell-specific transcription factor BSAP in a large panel of B-lymphoid cell lines. The human CD19 gene has been cloned, and several BSAP-binding sites have been mapped by in vitro protein-DNA binding studies. In particular, a high-affinity BSAP-binding site instead of a TATA sequence is located in the -30 promoter region upstream of a cluster of heterogeneous transcription start sites. Moreover, this site is occupied by BSAP in vivo in a CD19-expressing B-cell line but not in plasma or HeLa cells. This high-affinity site has been conserved in the promoters of both human and mouse CD19 genes and was furthermore shown to confer B-cell specificity to a beta-globin reporter gene in transient transfection experiments. In addition, BSAP was found to be the only abundant DNA-binding activity of B-cell nuclear extracts that interacts with the CD19 promoter. Together, this evidence strongly implicates BSAP in the regulation of the CD19 gene.

Animals↗
PubMed1992

Restraint-review committee: a working model.

Initially, the goal of this committee was to reduce the number of unnecessary physical restraints (see Table 4). This was achieved by a team approach and a systematic process of assessment, monitoring, and evaluation. In addition, this process provided a means by which restraint use could be thoroughly documented and functionally monitored. Efforts are continuing in order to provide a safe environment while at the same time promoting quality of life through reduction of restraints.

Aged↗
PubMed1991

Effect of amiloride on diaphragmatic contractility: evidence of a role for Na(+)-Ca2+ exchange.

Extracellular Ca2+ has been shown to be important for the normal function of the diaphragm. In this study we have examined the potential importance of Na(+)-Ca2+ exchange as a mechanism for Ca2+ influx during the contractile process by studying the effect of inhibition or stimulation of Na(+)-Ca2+ exchange. Blockade of Na(+)-Ca2+ exchange with amiloride attenuated the twitch response, altered the force-frequency response curve, and enhanced the development of fatigue. The effect of amiloride could be partially reversed by increasing the extracellular Ca2+ concentration. The ability of amiloride to decrease force was associated with decreased Ca2+ uptake by the diaphragm. Enhancing intracellular Na(+)-extracellular Ca2+ exchange by inhibiting the Na(+)-K+ pump significantly decreased the rate of the development of muscle fatigue (89%). The maximal inhibition of diaphragmatic force produced by the amiloride analogue benzamil, which possesses 10-fold greater selectivity for Na(+)-Ca2+ exchange, was not significantly different from that produced by amiloride (76.2 +/- 1.1%), with a concentration that decreased maximum force by 50% equal to 46 microM compared with 460 microM for amiloride. Both agents slowed the maximal rate of relaxation up to 90%. Benzamil elevated resting tension during continuous stimulation of the diaphragm at 0.15 Hz. The results suggest that Na(+)-Ca2+ exchange may have a role in the normal function of the diaphragm.

Amiloride↗
PubMed1990

Fluoride bioavailability from slow-release sodium fluoride given with calcium citrate.

Clinical pharmacology of slow-release sodium fluoride given with calcium citrate was examined in acute and long-term studies. Following a single oral administration of 50 mg slow-release sodium fluoride, a peak serum fluoride concentration (Cmax) of 184 ng/ml was reached in 2 h; thereafter, serum fluoride concentration declined with a T1/2 of 5.9 h. The concurrent administration of calcium citrate (400 mg calcium) gave an equivalent Tmax (time required to attain Cmax) and T1/2, but a lower Cmax of 135 ng/ml. The coadministration of a meal with fluoride also reduced Cmax but increased Tmax. The area under the serum concentration curve of slow-release sodium fluoride was reduced 17-27% by a meal or calcium citrate. Thus, calcium citrate reduced fluoride absorption and peak fluoride concentration in serum of slow-release sodium fluoride but did not affect the time required to reach peak concentration or the rate of subsequent decline. The effect of a meal was similar, except for a longer period required to reach peak serum concentration. During long-term administration of 25 mg slow-release sodium fluoride coadministered with 400 mg calcium as calcium citrate on a twice daily schedule, the trough level of serum fluoride could be kept between 95 and 190 ng/ml, believed to be the therapeutic window.

Adult↗
PubMed1990

Daylight saving time in psychiatric illness.

It has been reported that the change in photoperiod induced by the occurrence of daylight saving time has an effect on psychiatric presentation. We therefore investigated the impact of daylight saving time in three conditions: (1) parasuicide presentations; (2) psychiatric outpatient contacts, and inpatient admissions; (3) registered suicides. Results indicate that neither the change in photoperiod nor the effect of a small change in circadian rhythm associated with daylight saving time has an effect on 'cases' in any of the three conditions.

Circadian Rhythm↗
PubMed1990

Skeletal muscle limits the exercise tolerance of renal transplant recipients: effects of a graded exercise training program.

Sixteen renal transplant recipients were studied before and after they had participated in a 24-week exercise training program to determine (1) the nature of the factors explaining their impaired exercise tolerance, and (2) their adaptative responses to exercise training. During progressive treadmill exercise to exhaustion prior to training, renal transplant recipients stopped exercising at lower peak rates of oxygen consumption (VO2max) (29.0 +/- 7.8 47.9 +/- 9.1 mL O2.kg-1.min-1; P less than 0.001) and ventilation (55.9 +/- 13.2 v 124.0 +/- 22.2 L.min-1; P less than 0.0001), and at lower peak heart rates (169 +/- 22 v 196 +/- 9 beats.min-1; P less than 0.05) and peak blood lactate concentrations (5.0 +/- 2.1 v 11.5 +/- 4.0 mmol.L-1; P less than 0.001) than did controls. None showed a plateau in oxygen consumption with increasing workload. Exercise time to exhaustion was also significantly shorter in renal transplant recipients (9.5 +/- 1.8 v 16.0 +/- 1.3 min; P less than 0.0001). After training, exercise time to exhaustion (12.0 +/- 2.0 min; P less than 0.001), VO2max (37.5 +/- 4.8 mL O2.kg-1.min-1; P less than 0.05), maximum ventilation rate (68.5 +/- 14.0 L.min-1; P less than 0.05), peak blood lactate concentrations (7.8 +/- 1.8 mmol-L-1; P less than 0.001), and the rate of oxygen consumption at a blood lactate concentration of 2.0 mmol.L-1 (22.5 +/- 2.5 v 16.5 +/- 2.2 mL O2.kg-1.min-1; P less than 0.001) had all increased significantly.(ABSTRACT TRUNCATED AT 250 WORDS)

Adaptation, Physiological↗
PubMed1990

An E. coli expression system for the rapid purification and characterization of a v-abl tyrosine protein kinase.

A bacterial expression vector containing a segment of the v-abl gene from Abelson murine leukemia virus (A-MuLV) was constructed such that the gag region of v-abl was replaced by a sequence encoding the IgG-binding domain of the S. aureus protein A. pabl HP, a fusion protein encoded by this vector was rapidly purified to near homogeneity by affinity chromatography on IgG-Affigel and Mono Q FPLC. The Km of the pabl HP kinase for ATP varied with [Val5]-angiotensin II concentration and was 21.2 microM at saturating concentrations of [Val5]-angiotensin II. The Km for [Val5]-angiotensin II at saturating concentrations of ATP was 3.8 mM. The turnover number, at 20 degrees C, was 62 mumol min-1 mumol-1. Initial rate studies support a ternary complex kinetic mechanism for phosphoryl transferase. The substrate specificity of the pabl HP kinase was further characterized using synthetic peptides. This expression system, which enables the rapid purification of recombinant v-abl kinase is suitable for the comparative enzymological study of mutant v-abl enzymes generated by site-directed mutagenesis.

Abelson murine leukemia virus↗