Search PubMed⌕ Search

Biomedical subjects

S J Roberts

Publications and source records attributed to S J Roberts.

At least 73 records · Page 4Linked to original sources

Negotiated and nonnegotiated nurse-patient interactions: enhancing perceptions of empowerment.

Ninety-eight students with upper respiratory symptoms participated in a study to determine differences in patient perceptions of two types of nurse-patient interactive styles. Subjects participated in either an actively negotiated process of decision making (n = 53) or a nonnegotiated approach (n = 45) with a nurse. Findings revealed that subjects in the negotiated group perceived significantly greater feelings of control and power in the nurse-patient relationship than did the nonnegotiated group. No significant correlations were found between motivation and patient perceptions of the interaction. Study results demonstrate that nurses can engage in an active negotiation process with patients and strongly influence feelings of control in decision making.

Adolescent↗

Lesbian health care: a review and recommendations for health promotion in primary care settings.

Lesbians are often "invisible" in primary care settings and literature. They frequently feel anxious, mistreated, and misunderstood by providers if they reveal their sexuality. Increasingly these women are "coming out" to providers and asking for knowledgeable and sensitive care. This article reviews the literature on lesbian health care and makes suggestions about history taking and health promotion that is sensitive to the needs of lesbian clients.

Female↗

Lymphocyte proliferation in mice congenitally deficient in T-cell receptor alpha beta + cells.

In mice and humans, T cells are characterized on the basis of T-cell receptor (TcR) expression and divided into the major TcR alpha beta + and minor TcR gamma delta + populations. TcR alpha beta + cells are considered to be the primary regulators of the immune response, whereas the function of TcR gamma delta + cells is unclear. Mice congenitally deficient in TcR alpha beta-expressing cells provide an ideal model for analyzing the independent in vivo function of TcR gamma delta + cells in the absence of TcR alpha beta + cells. Here we report that lymphoid organs in TcR alpha mutant mice undergo substantial enlargement after being challenged by environmental antigens. This organ expansion can be attributed in part to increases in the relative proportions and absolute numbers of TcR gamma delta + cells, but an expansion of the recently described TcR beta + alpha - population also has a role. The expansion of the TcR gamma delta + population is polyclonal, as evidenced by the usage of multiple gamma and delta variable chain segments. Furthermore, a substantial proportion of the cells appears to be activated and these activated cells express surface activation markers. The results clearly demonstrate that TcR gamma delta + cells proliferate independently in response to a broad spectrum of challenges. Moreover, since the expansion of the lymphoid tissues and the TcR gamma delta + cell population is excessive relative to that seen in wild-type animals, one role of TcR alpha beta + cells is directly or indirectly to limit the responses of the other lymphoid components.

Animals↗

Immunoglobulin synthesis and generalized autoimmunity in mice congenitally deficient in alpha beta(+) T cells.

Through cognate B-cell-T-cell interactions and provision of cytokines, CD4+ T-cell antigen receptor (TCR) alpha beta+ T cells regulate immunoglobulin isotype synthesis. Murine IgG1 and IgE secretion is therefore substantially T-cell-dependent, whereas IgM and IgG3 secretion is not. Here we report that in the absence of alpha beta T cells, B cells expand, differentiate and secrete copious amounts of antibodies of 'T-dependent' isotypes. Moreover, the antibodies are reactive towards self-antigens, as in patients with systemic lupus erythematosus, so autoantibodies of 'T-dependent' type can develop without the help of CD4+ alpha beta T cells. This phenotype is not evident in mice or humans that are congenitally deficient in specific alpha beta T-cell functions, but bears comparison with B-cell hyperactivity and autoimmunity in transplant rejection and in immunodeficiencies such as AIDS.

Animals↗

The use of nitrates, calcium channel blockers and ACE inhibitors in primary care in the Northern Region: a pharmacoepidemiological study.

1. Prescribing rates for cardiovascular drugs have substantial local variation. The objectives of this study were to determine the prescribing prevalence of nitrates, calcium channel blockers and angiotensin-converting enzyme inhibitors in general practice, to examine the indications recorded for these prescriptions, and to identify which therapeutic areas contribute to the variation in prescribing. 2. Anonymised patient-specific prescription data were taken from computerised records in 41 VAMP research practices in the Northern Region (total population 330,749). All patients who received any prescription for calcium channel blockers, nitrates or angiotensin-converting enzyme (ACE) inhibitors during a 12 month period were included. Prescribing rates were determined in terms of patients per 1,000 population within age, sex and diagnostic groups. 3. Overall, 4.3% of the study population were prescribed one or more of the drugs. There was virtually no prescribing for patients under the age of 35 years, but thereafter the prevalences rose steeply to peak at ages 65-74 years for calcium channel blockers (91 per 1,000 population) and ACE inhibitors (34 per 1,000), and at ages 75-84 years for nitrates (100 per 1,000). Prescribing prevalence amongst the over 85's was less than half the peak rate for each drug group. Rates for men and women were comparable, except for nitrates where men had higher rates. 4. Recorded indication rates for patients with ischaemic heart disease and treated with any of these drugs reached 112 per 1,000 population in the 75-84 age group, and were higher in men than women, at all ages. Hypertension indication rates were substantially higher in women over 65; across the genders the peak rate was 88 per 1,000 for those aged 65-74 years.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Carbofuran-degrading bacteria from previously treated field soils.

Laboratory incubation studies were made on soils collected from five field sites with different histories of treatment with carbofuran. All soils treated earlier with carbofuran degraded the compound more rapidly than untreated samples of the same soils. Reduced rates of degradation in the presence of chloramphenicol imply that soil bacteria are primarily responsible for the breakdown of carbofuran in these soils. Sixty-eight bacteria, capable of degrading carbofuran as the sole source of carbon and nitrogen, were isolated from liquid cultures of treated soils. The concentration of carbofuran in the liquid medium used for isolation and subsequent culture of carbofuran-degrading isolates appeared to affect the stability of their ability to degrade. Similar types of carbofuran-degrading bacteria were isolated from different soils and several different types were isolated from one soil. All carbofuran-degrading isolates were Gram-negative, aerobic rods which hydrolysed the insecticide to carbofuran phenol. They were separated into four groups on the basis of a limited number of phenotypic characters. There was a good correlation between the phenotype of carbofuran-degrading isolates and the stability of their ability to degrade. Fourteen isolates were placed in phenotypic group I and 13 of these did not degrade carbofuran after one subculture in liquid medium. Phenotypic groups II, III and IV consisted of 54 isolates in total (3, 46 and 5 isolates respectively) and 52 of these retained their ability to degrade carbofuran when subcultured.

Biodegradation, Environmental↗

Rapid degradation of the triazinone herbicide metamitron by a Rhodococcus sp. isolated from treated soil.

Seven bacterial isolates which degraded the herbicide metamitron (3-methyl-4-amino-6-phenyl-1,2,4-triazin-5-one) were obtained from field-enhanced soil by liquid enrichment culture. All isolates appeared to be identical and a representative, 0246b, was identified as a Rhodococcus sp. by cell wall and fatty acid analyses. This isolate degraded metamitron as the sole source of carbon within 24 h at 25 degrees C and this is the first report of a bacterium capable of growing with metamitron as the sole source of carbon. Metamitron was degraded less rapidly when it was the sole source of both carbon and nitrogen. The rate and extent of degradation was affected by the presence and type of additional sources of carbon and nitrogen in the culture medium. In studies with [14C]-phenyl-labelled metamitron Rhodococcus sp. 0246b partly mineralized the phenyl ring.

Biodegradation, Environmental↗

Which patients are prescribed inhaled anti-asthma drugs?

BACKGROUND: Prescribing rates for inhaled anti-asthmatic drugs in the UK vary considerably from area to area and between individual practices. The objectives of this study were to determine the prevalence of patients prescribed inhaled steroids and beta agonist bronchodilators, the indications for these prescriptions, and to relate prescribing to the recorded levels of morbidity for specific respiratory disease. METHODS: Anonymised patient-specific prescription and diagnostic data were extracted from computerised general practice records for the 41 practices in the Northern region (total population 330,749) whose data had been validated for inclusion in a research databank. Patients were included if they were either prescribed an inhaled steroid or bronchodilator during a 12 month period, or had a recorded diagnosis of asthma, bronchitis or chronic obstructive pulmonary disease. Prescribing of inhalers per 1000 population was determined within age, sex, and diagnostic groups. Respiratory diagnosis rates within different patient groups were used to measure the underlying level of morbidity in the population. RESULTS: Inhaled anti-asthma drugs were prescribed for 5% of the study population. Prescribing prevalences peaked at ages 5-14 (steroids 40 per 1000 population; bronchodilators 68 per 1000) and at ages 65-74 (steroids 53 per 1000; bronchodilators 79 per 1000). Prescribing frequency for both drugs increased from two or three items per patient annually at age 0-14 to about six in the over 65 age group. Of the 39,424 respiratory patients 38% received inhalers and 7% only non-inhaler medication. Inhaler therapy was used in only 6% of patients with bronchitis, but in 66% of those with asthma, though the proportions varied with patient age and gender. Study practices differed in their overall levels of both inhaler prescribing and respiratory diagnosis, and had lower prescribing patterns of these drugs than other practices in the Northern region. CONCLUSIONS: Inhaled steroid and bronchodilator prescribing have age-related and gender-related prevalences. Treatment for respiratory diagnoses varies with patient age and gender, and with the diagnosis. Prescribing differences between practices are attributable to variation in both diagnostic rates for respiratory disease and therapeutic intervention patterns. For asthma patients study practices show consensus in approach, perhaps illustrating the value of clear guidelines for asthma prescribing.

Administration, Inhalation↗

Somatization in primary care. The common presentation of psychosocial problems through physical complaints.

Somatization is a common problem in primary care. It has been estimated that up to 75% of all visits to primary care providers involve presentation of psychosocial problems through physical complaints. The patient with an acute problem may respond to education, support and reassurance. The chronic somatizer often has a history of inadequate coping, painful interpersonal relationships, and frequent but unsatisfying relationships with health care providers. The etiology of somatization involves a combination of social, psychological and cultural variables. A careful and holistic assessment of complaints and psychosocial aspects is vital in order to avoid extensive diagnostic evaluations and treatments which do not help and may put them at risk for iatrogenic illness. Specific strategies that emphasize a caring, supportive relationship are useful. The NP may need consultation from medical and mental health colleagues to assist in the behavioral management of the chronic somatizer.

Diagnosis, Differential↗

Age, sex, and temporary resident originated prescribing units (ASTRO-PUs): new weightings for analysing prescribing of general practices in England.

OBJECTIVE: To derive demographic weightings to replace the existing system of prescribing units used in analysing prescribing by general practitioners in England. DESIGN: The prescribing data for one year from a sample of 90 practices in 80 family health service authority areas were used to calculate the relative frequency with which items were prescribed, for each sex, in nine age bands and for temporary residents. Data on the variation in cost per item by age and sex then allowed estimates to be made of the relative costs for these groups. Integer values for both the item based and cost based weightings were obtained by conversion to optimal integer scales. MAIN OUTCOME MEASURES: Item based and cost based weightings for each of the 18 age-sex groups and for temporary residents. The cost based weightings were considered more appropriate to the context in which the new system was to be used. RESULTS: Prescribing costs increased noticeably, for both sexes, in the middle years (ages 35-64). Compared with the existing system, the cost based weightings (ASTRO-PUs) gave greater weight to patients aged 45 and over, especially those in the 55-64 age band, at the expense of younger patients. Children under 5 received twice as many items as those aged 5-14, but the inexpensiveness of their drugs made the cost based weightings of the two groups equal. Similarly, women were generally given more items than men, but at a lower average cost per item, which reduced differences between the sexes in the cost based weightings. Costs for patients aged 75 and over, compared with those aged 65-74, were higher only for women. CONCLUSIONS: The cost based weightings proposed are believed to reflect the present distribution of prescribing costs, in relation to age and sex, in English general practice. They are intended for use in analyses at practice level.

Adolescent↗

Dynamic response of murine gut intraepithelial T cells after infection by the coccidian parasite Eimeria.

The response of murine intraepithelial lymphocyte (IEL) populations to challenge by Eimeria vermiformis, a naturally occurring protozoan parasite of the gut epithelium, has been studied. The number of recoverable IEL increased within 3 days post infection, was depleted by day 7 post infection, but was significantly increased again by about day 14 post infection. Special attention was paid to gamma delta+ IEL T cells, because they are of unknown functions. These cells showed changes in numbers similar to the total IEL population. Moreover, by day 3, increased expression was detected among gamma delta+ IEL T cells, of T cell receptor genes not constitutively associated with the intestine. These results demonstrate that the IEL repertoire, and within that, the gamma delta+ T cell repertoire, can be extremely dynamic post infection with a naturally occurring epithelial-tropic pathogen. In considering the potential benefits of such IEL changes, we hypothesize that they may be relevant to the transient protection of the host's epithelium, both from parasitic re-infection, and from potentially damaging inflammation.

Animals↗

Characterization of propranolol-resistant (-)-[125I]-cyanopindolol binding sites in rat soleus muscle.

1. The characteristics of a propranolol-resistant (-)-[125I]-cyanopindolol (CYP) binding site in rat soleus muscle were determined. 2. Saturation studies performed on homogenates of rat soleus muscle showed two phases of (-)-[125I]-CYP binding, a high affinity site (KD1 30.5 +/- 16.3 pM, Bmax 9.4 +/- 1.38 fmol mg-1 protein) and a lower affinity site (KD2 522.5 +/- 29.1 pM, Bmax 62.19 +/- 11.76 fmol mg-1 protein, n = 4). 3. In rat soleus muscle homogenates labelled with (-)-[125I]-CYP (500 pM), (-)-propranolol competition curves were biphasic with pKD values of 8.30 +/- 0.19, and 5.33 +/- 0.08, n = 7. 4. Competition between (-)-[125I]-CYP (500 pM) and (+/-)-tertatolol, (+/-)-nadolol, (+/-)-alprenolol, (+/-)-CYP, and (-) and (+)-pindolol showed that these compounds competed for binding at the propranolol-resistant site with affinities lower than those displayed at typical beta-adrenoceptors. The atypical beta-adrenoceptor agonists BRL 37344, SR58611A and ICI D7114 and the partial agonist (+/-)-CGP 12177 also competed for (-)-[125I]-CYP binding. 5. Stereoselectivity was demonstrated for the stereoisomers of alprenolol and tertalolol. The (-)-isomers of alprenolol and tertalolol had higher affinity than their corresponding (+)-isomers (3.1 and 2.6 fold respectively). These low stereoselectivity values are a characteristic of atypical beta-adrenoceptors. 6. The beta-adrenoceptor agonists, (-)-adrenaline, (-)-isoprenaline and (-)-noradrenaline, all showed lower affinity than the atypical beta-adrenoceptor agonists and competition curves appeared biphasic in nature. 7. These results confirm the presence of a propranolol-resistant (- )-[125I]-CYP binding site in rat soleus muscle. The affinities of the tested compounds at the propranolol-resistant (- )-[125I]-CYP binding site show similarities to their affinities at 'atypical' beta-adrenoceptors in adipocytes and gastrointestinal tissues and at the cloned beta 3-adrenoceptor.

Adrenergic beta-Agonists↗

Expression and characterization of glycophospholipid-anchored human immunodeficiency virus type 1 envelope glycoproteins.

Four chimeric human immunodeficiency virus type 1 (HIV-1) env genes were constructed which encoded the extracellular domain of either the wild-type or a cleavage-defective HIV-1 envelope glycoprotein (gp160) fused at one of two different positions in env to a C-terminal glycosyl-phosphatidylinositol (GPI) attachment signal from the mouse Thy-1.1 glycoprotein. All four of the constructs encoded glycoproteins that were efficiently expressed when Rev was supplied in trans, and the two cleavable forms were processed normally to gp120 and a chimeric "gp41." The chimeric glycoproteins, in contrast to the wild-type glycoprotein, could be cleaved from the surface of transfected cells by treatment with phosphatidylinositol-specific phospholipase C, indicating that they were anchored in the plasma membrane by a GPI moiety. These GPI-anchored glycoproteins were transported intracellularly at a rate only slightly lower than that of the full-length HIV-1 glycoprotein and were present on the cell surface in equivalent amounts. Nevertheless, all four glycoproteins were defective in mediating both cell-cell and virus-cell fusion as determined by syncytium formation in COS-1-HeLa-T4 cell mixtures and trans complementation of an env-defective HIV-1 genome.

Amino Acid Sequence↗

Arterial blood pressure responses to graded transient arousal from sleep in normal humans.

During obstructive sleep apnea, transient arousal at the resumption of breathing is coincident with a substantial rise in blood pressure. To assess the hemodynamic effect of arousal alone, 149 transient stimuli were administered to five normal subjects. Two electroencephalograms (EEG), an electrooculogram, a submental electromyogram (EMG), and beat-to-beat blood pressure (Finapres, Ohmeda) were recorded in all subjects. Stimulus length was varied to produce a range of cortical EEG arousals that were graded as follows: 0, no increase in high-frequency EEG or EMG; 1, increased high-frequency EEG and/or EMG for < 10 s; 2, increased high-frequency EEG and/or EMG for > 10 s. Overall, compared with control values, average systolic pressure rose [nonrapid-eye-movement (NREM) sleep 10.0 +/- 7.69 (SD) mmHg; rapid-eye-movement (REM) sleep 6.0 +/- 6.73 mmHg] and average diastolic pressure rose (NREM sleep 6.1 +/- 4.43 mmHg; REM sleep 3.7 +/- 3.02 mmHg) over the 10 s following the stimulus (NREM sleep, P < 0.0001; REM sleep, P < 0.002). During NREM sleep, there was a trend toward larger blood pressure rises at larger grades of arousal (systolic: r = 0.22, 95% confidence interval 0.02-0.40; diastolic: r = 0.48, 95% confidence interval 0.31-0.62). The average blood pressure rise in response to the grade 2 arousals was approximately 75% of that during obstructive sleep apnea. Arousal stimuli that did not cause EEG arousal still produced a blood pressure rise (mean systolic rise 8.6 +/- 7.0 mmHg, P < 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗