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Biomedical subjects

A Campbell

Publications and source records attributed to A Campbell.

At least 163 records · Page 9Linked to original sources
PubMed1991

The relationship between neuropsychological measures and self-care skills in patients with cerebrovascular lesions.

The present investigation examined the relationship between performance on the Michigan Neuropsychological Battery (MNB) and selected self-care skills in a group of patients with unilateral cerebrovascular lesions. Among MNB measures, left-sided somatosensory and motor functions were the best predictors of self-care skills, showing that in these stroke patients lower level cerebral functions mediated by the right hemisphere are more strongly related to the self-care skills examined than higher cerebral functions. Also, evidence that patients with cerebrovascular lesions in the left hemisphere performed better than patients with right hemisphere lesions in several self-care categories is further indication that right hemisphere processes have a special role to play in the mediation of these self-care activities. The research and clinical implications of these findings are noted.

Activities of Daily Living↗
PubMed1991

Neuropsychological studies of blacks with cerebrovascular disorders: a preliminary investigation.

Very few studies have been conducted that examine brain behavior functions in blacks and other ethnic minorities. Recognizing that measures of higher cortical functions have cultural, experiential, and organic determinants, the present investigation was designed to ascertain whether findings reported in neuropsychologic studies of white patients with lateralized cerebral lesions are applicable to groups of black patients with lesions in similar locations. Thirty-seven patients with left (n = 15) and right (n = 22) cerebrovascular lesions were administered the Michigan Neuropsychological Battery (MNB). This battery is comprised of a number of objective standardized measures of higher and lower-level cerebral functions. With one exception, the performance of patients in the brain-injured groups was not systematically different on tests of higher brain functions. As expected, tests of lower-level somatosensory and motor functions showed a pattern of greater impairment on the side of the body contralateral to the lesion. But, in contrast to neuropsychological studies of white patients, a pattern of laterality specific deficits on verbal IQ and performance IQ was not observed. Methodological and theoretical implications of these findings are discussed.

Analysis of Variance↗
PubMed1990

Cyclical differentiation of Trypanosoma brucei involves changes in the cellular complement of calmodulin-binding proteins.

The present study was undertaken to evaluate changes in the complement of calmodulin-binding proteins which accompany cyclical differentiation in Trypanosoma brucei. An [125I]trypanosome calmodulin overlay procedure was used to detect calmodulin-binding proteins with Mr of 126,000 and 106,000 that were present in homogenates of slender bloodstream froms but were absent in procyclic culture forms. Competition assays with unlabeled bovine brain or trypanosome calmodulins indicated that the developmentally regulated proteins associated with calmodulins from either source. Moreover, [125I]bovine brain calmodulin associated with the same proteins as trypanosome calmodulin. Homogenates of T. evansi exhibited the same pattern of calmodulin-binding activity as T. brucei slender bloodstream forms; however, T. cruzi and Leishmania tarentolae contained distinct patterns of calmodulin-binding activity. Mouse serum contained no detectable binding proteins while mouse brain contained predominantly proteins of Mr 210,000, 60,000, and 49,000 which were associated with the trypanosome calmodulin probe. The developmentally regulated calmodulin-binding proteins from T. brucei were in the 10,000g pellet. We conclude that the cellular complement of calmodulin-binding proteins varies during the trypanosome life cycle.

Animals↗
PubMed1990

R(-) and S(+) stereoisomers of 11-hydroxy- and 11-methoxy-N-n-propylnoraporphine: central dopaminergic behavioral activity in the rat.

R(-)11-Hydroxy-N-n-propylnoraporphine (11-OH-NPa) induced stereotyped behavior in the rat as potently (ED50 = 0.80 mg/kg, i.p.) as R(-)apomorphine (APO) and this effect was blocked by haloperidol; the 11-methoxy congener, R(-)11-MeO-NPa, had a weak effect (ED50 greater than 10 mg/kg) and the S(+) isomers had none. The isomer R(-)11-OH-NPa potentiated locomotion stimulated by apomorphine; S(+)11-OH-NPa inhibited it and the isomers of 11-MeO-NPa were inactive. Catecholaporphines usually are inactive orally, but both R(-) and S(+)11-OH-NPa were similarly potent after oral or parenteral administration. The isomer S(+)11-OH-NPa inhibited spontaneous and apomorphine-induced locomotion (ID50 = 1.8-2.7 mg/kg, p.o. and i.p.) and stereotyped behavior (ID50 = 3 mg/kg, p.o. or i.p.), all without inducing catalepsy. While apomorphine was short-acting (1-2 hr), the effects of R(-)11-OH-NPa persisted up to 6-7 hr and those of the S(+) isomer for at least 2.5 hr; moreover, the efficacy of R(-)11-OH-NPa increased markedly up to 3-4 hr, although its ED50 was independent of time (ED50 = 1.7-1.9 mg/kg, i.p. from 1-3 hr). The total effect of R(-)11-OH-NPa (p.o. or i.p.) over time was more than 10-times greater than that of injected apomorphine. These observations accord with the reported high (nM) affinity of 11-OH-NPa at cerebral DA receptor sites (D2 greater than D1) and weak interactions of the 11-methoxy congener. They support the conclusion that the R(-) and S(+) stereoisomers are neuropharmacologically active, respectively, as DA agonist and apparent antagonist, as was found with the enantiomers of N-n-propylnorapomorphine, perhaps due to the low intrinsic postsynaptic agonist activity of the S(+) isomers. Moreover, 11-OH-NPa was highly bioavailable orally and unusually long-acting; it may be absorbed slowly or have active metabolites. Hydroxy-substitution of aporphines at the 11-position, homologous to the 3-OH of DA, evidently is critical for affinity and activity at the DA receptor. These or other monohydroxyaporphines may represent leads to potentially useful DA agonist or antagonist drugs.

Animals↗
PubMed1990

Conceptual models of the professions and their implications for the professionalization of health administration.

The extent to which health administration can be considered a profession is examined in the context of the five major models of the professions in the literature (historical, trait, functional, economic and power). A synthesis of the various models into a proposed integrative model, or typology of occupations, is also presented. Control over entry and control over conduct are identified as the two major dimensions by which the professional status of various occupations is measured. Health administration is seen as a profession in this context, and the prospects for further professionalization are discussed.

Canada↗
PubMed1990

Synthesis and structural requirements of N-substituted norapomorphines for affinity and activity at dopamine D-1, D-2, and agonist receptor sites in rat brain.

A series of N-substituted analogues of (R)-(-)-norapomorphine were synthesized to study the optimal structural requirements of the N-alkyl side chain to interact with D-1 and D-2 dopaminergic receptors as well as dopamine (DA) agonist binding sites. Evaluations included testing the affinity of these compounds for DA receptor sites in rat striatal tissue and assessing stereotypy as a behavioral index of dopaminergic activity. The electronic, steric, and lipophilic properties of the N-alkyl side chain were found to be related to affinity, D-2 selectivity, and dopaminergic activity. All 11 compounds evaluated had relatively low affinity at D-1 sites. Optimum D-2 and agonist-site affinity as well as agonist activity were exhibited by N-cyclopropylmethyl (7) greater than or equal to N-allyl (8) greater than or equal to N-propyl (4) or N-ethyl (3) substituted compounds. Branching of the N-alkyl side chain as in N-isopropyl (5) and N-isobutyl (6) markedly reduced the D-2 affinity and activity, presumably due to steric effects. The N-trifluoroethyl (10) and N-pentafluoropropyl (11) derivatives had low affinity for all their dopamine receptor sites and no agonistic activity; evidently, the highly electronegative F atoms decrease basicity of the N atom and therefore decrease the ability of the N atom to be cationic at physiological pH, a proposed requirement for high-affinity binding to DA receptors.

Animals↗
PubMed1990

Cloning and nucleotide sequence of bisC, the structural gene for biotin sulfoxide reductase in Escherichia coli.

Clones of the Escherichia coli bisC locus have been isolated by complementing a bisC mutant for growth with d-biotin d-sulfoxide as a biotin source. The complementation properties of deletions and Tn5 insertions located the bisC gene to a 3.7-kilobase-pair (kbp) segment, 3.3 kbp of which has been sequenced. A single open reading frame of 2,178 bp, capable of encoding a polypeptide of molecular weight 80,905, was found. In vitro transcription of plasmids carrying the wild-type sequence and deletion and insertion mutants showed that BisC complementation correlated perfectly with production of a polypeptide whose measured molecular weight (79,000) does not differ significantly from 80,905.

Amino Acid Sequence↗
PubMed1990

Clinical and scintigraphic assessment of the role of endoscopic sphincterotomy in the treatment of sphincter of Oddi dysfunction.

Postcholecystectomy pain caused by sphincter of Oddi dysfunction remains a difficult condition to treat. Endoscopic sphincterotomy has been recommended for those patients with confirmed sphincter of Oddi motor abnormalities. We have studied sphincter of Oddi dysfunction patients to evaluate the effects of endoscopic sphincterotomy on both clinical symptoms and previously reported scintigraphic parameters to determine the efficacy of this method of treatment. Nine postcholecystectomy patients (seven women: two men, median age 59 years) with clinical and manometric evidence of sphincter of Oddi dysfunction underwent endoscopic sphincterotomy for persisting biliary type pain. Each patient had scintigraphy before and eight weeks after endoscopic sphincterotomy. The patients symptomatic response was assessed independently at three monthly intervals after endoscopic sphincterotomy. Scintigraphic analysis showed that the TMAX (time in minutes to maximum counts) was significantly reduced from 25.0 (20-36) (median [range]) before endoscopic sphincterotomy to 15.0 (13-25) after endoscopic sphincterotomy (p less than 0.01). Seven of nine (78%) sphincter of Oddi dysfunction patients had significant improvement in their symptoms after a mean follow up period of 12 months (range 6-19) although only six of nine were totally pain free. These results suggest that endoscopic sphincterotomy in manometrically confirmed sphincter of Oddi dysfunction improves bile drainage as measured by quantitative cholescintigraphy and is associated with at least short term symptom relief in the majority of patients.

Adult↗
PubMed1990

Systemic vasculitis in the 1980s--is there an increasing incidence of Wegener's granulomatosis and microscopic polyarteritis?

Thirty-six cases of Wegener's granulomatosis (WG) and microscopic polyarteritis (MPA) presenting to the nephrology service in Leicester between 1980 and 1989 were reviewed. Apart from the diagnostic respiratory tract lesions seen in WG, cases of MPA and WG could not be distinguished by age and sex, range and severity of organ involvement, response to treatment (oral prednisolone and cyclophosphamide), mortality or renal outcome. The combined incidence of WG and MPA in 1980-86 was 1.5/million/year. Following the introduction in January 1987 of an assay for anti-neutrophil cytoplasmic antibody (ANCA), the incidence of WG and MPA increased in 1987-89 to 6.1/million/year (p less than 0.0001). Cases seen during these two periods did not differ by any clinical parameter except that later cases had less severe renal disease at referral and improved renal outcome. Median serum creatinine was significantly lower at presentation in 1987-89 (p less than 0.02). Of those surviving 3 months from presentation only 1/20 in 1987-89 had end stage renal failure compared with 4/10 in 1980-86 (p less than 0.02). These findings may reflect increasing diagnostic awareness of WG and MPA among physicians since the introduction of ANCA.

Adult↗
PubMed1990

Stability of home blood pressure over time.

In the initial assessment of mild hypertensive patients a prolonged period of repeated measurement is necessary to ensure accurate diagnosis. Home monitoring of blood pressure (BP) may accurately predict those patients whose hypertension will be 'sustained' in a clinic environment and it is important therefore to establish whether average home BP is stable on repeated assessment. Seventeen patients found to be hypertensive on screening were recalled after two weeks and again after four weeks for further BP measurement. All patients monitored home BP over 3 days following each clinic visit. Clinic BP fell from the first to last visit (181 +/- 4/97 +/- to 162 +/- 5/93 +/- 2 mmHg, P less than 0.05) with no change in home BP over the same period (153 +/- 3/89 +/- 3 to 154 +/- 4/89 +/- 3 mmHg). It is clear therefore that an average home BP produced during three days of monitoring is a stable measurement at least over a four week period and thus in the initial assessment of a hypertensive patient this technique may allow for greater diagnostic accuracy.

Ambulatory Care↗
PubMed1989

Reduced cell adhesion to fibronectin and laminin is associated with altered glycosylation of beta 1 integrins in a weakly metastatic glycosylation mutant.

A weakly metastatic wheat-germ-agglutinin-resistant mutant Wa4-b1 was previously shown to be less adherent to endothelial cell extracellular matrix than the more metastatic parental B-16 melanoma cells. This report describes reduced adhesion and spreading of Wa4-b1 cells on the cell-binding domain of fibronectin (CBD) and laminin (LN). Cell surface receptors which mediate such interactions are members of the integrin family of membrane glycoproteins. An antibody that recognizes the beta 1 integrin subunit inhibited spreading on both the CBD and LN. The integrins of the mutant cells immunoprecipitated by the antibody appeared to be structurally altered, showing a greater electrophoretic mobility. The mobility difference between the parent and the mutant receptors was abolished following removal of the glycan moieties of the receptors enzymatically using glycopeptidase F, or chemically using trifluoromethanesulfonic acid, suggesting that the structural alteration of the mutant receptors is in glycosylation. The altered receptors may be responsible for the observed decrease in cell adhesion and spreading of the mutant cells to the CBD and LN. Such a decrease in Wa4-b1 cell interaction with extracellular matrix components may play a role in their decreased metastatic potential.

Animals↗
PubMed1989

Bromocriptine antagonizes behavioral effects of cocaine in the rat.

Rats given cocaine or bromocriptine under conditions of low basal arousal showed dose-dependent increases of locomotor activity for less than or equal to 1 hours, followed by depression of activity that diminished gradually over the next 2 hours. Arousal was related biphasically to dose (maximum at ca. 5 mg/kg) but depression increased monophasically with the dose of either agent. Both behavioral arousal and depression induced by cocaine were antagonized by bromocriptine, even at doses lacking behavioral effects alone (ID50 = 1.0 and 0.36 mg/kg [1.3 and 0.5 mumol/kg], respectively). Bromocriptine blocked depression of locomotion even when given after the initial stimulation by cocaine. Bromocriptine induced very weak stereotypy, and neither increased nor blocked stereotypy induced by cocaine or apomorphine. Cocaine, at maximally effective doses, did not deplete catecholamines or serotonin in brain regions at times of maximum behavioral arousal or depression, nor did bromocriptine after metabolic turnover of dopamine. Bromocriptine antagonized arousal induced by direct injection of dopamine into the nucleus accumbens. The ability of bromocriptine to block both the behavioral arousal and depression induced by cocaine may reflect activity of bromocriptine as a mixed agonist-antagonist with limited intrinsic agonistic activity at central dopaminergic D2 receptors, perhaps with particular reference to limbic mechanisms.

Animals↗
PubMed1989

Women's group therapy: a clinical experience.

Women compose three-fourths of the psychiatric patient population in one clinical facility. A women's therapy group was formed to help the women change their attitudes and behaviors of helplessness and dependency. The goals of the group were for participants to get in touch with and express their feelings, and to become more assertive and autonomous. Group themes centered around depression, denial, resistance, and autonomy. The therapy group provided an opportunity for the women to learn more about themselves, their culture, and the value of giving and receiving support to and from each other.

Dependency, Psychological↗
PubMed1988

Transcriptional regulation and gene arrangement of Escherichia coli, Citrobacter freundii and Salmonella typhimurium biotin operons.

The bio operons of Citrobacter freundii and Escherichia coli K-12 (strain C600) were isolated by screening lambda banks for complementation of E. coli bio mutants. These were compared with the previously isolated bio operon of Salmonella typhimurium and previous data on E. coli K-12. The restriction maps of the operon are very different in the three species, but no difference in gene order was found. Operator-promoter DNA, identified by repressible titration and by biotin-repressible transcription in E. coli, was sequenced and compared to the published E. coli K-12 sequence. In the segment previously identified as operator/bioB promoter, C. freundii and S. typhimurium DNA are identical and differ from E. coli only by 2 bp. The DNA to the right of this segment (indicated by previous data to be the bioA promoter of E. coli) has diverged in all three species, and only E. coli has a sequence resembling a consensus promoter.

Bacteriophage lambda↗