Biomedical subjects
Publications and source records attributed to A Richardson.
The frequency of the cells bearing the naive marker (OX22+) in T cells, helper, and cytotoxic/suppressor T cell subsets isolated from the spleens of young and old F344 rats were measured by flow cytometry. The percentage of naive cells in T cells decreased significantly with age and this decline occurred primarily in the helper subset.
We previously reported evidence in university students of three syndromes of schizotypy which have strong affinities with three-syndrome models of schizophrenia. As in schizophrenia two of the syndromes were associated with opposite hemispheric asymmetry patterns: an Active syndrome with a left > right asymmetry, and a Withdrawn syndrome with a right > left asymmetry. The third Unreality syndrome bore no consistent relation to pattern of asymmetry. Cognitive asymmetry was measured by comparing recognition memory for words with memory for unfamiliar faces using a neuropsychological test which assesses temporoparietal functions. Here the same approach was extended to the broader concept of psychosis proneness with a new inventory with four subscales: Introvertive Anhedonia, Impulsive Nonconformity. Unusual Experiences, and Cognitive Disorganisation. In support of the relevance of an activation dimension to cognitive asymmetry, Impulsive Nonconformity was associated with word > face superiority, as was a self report measure of Energy. Introvertive Anhedonia was associated with face > word superiority. As in schizophrenia these predicted asymmetry relations were significant in males only. Neither the Unusual Experiences nor Cognitive Disorganisation subscales were associated with cognitive asymmetry.
Using combined medical and drug clinics, by the end of 1990 we had initiated contact with 511 HIV positive individuals, 75% injection drug use (IDU) related. We have previously reported a significant reduction in the number of missed appointments from 1985-89 following the introduction of methadone and an all day clinic, but between 1989 and 1990 the appointment default rate rose from 17 to 25%. A significant percentage increase in missed appointments was, however, only seen in those not attending the all day clinic (chi 2(3) = 121.3, p < 0.001). An analysis of the patients missing appointments during 1989-90 revealed that 36-45% of patients attending each year missed only 1 or 2 appointments, that the majority of missed appointments each year were accounted for by less than 20% of the patients, around 60% of these patients missed appointments in both years and that only 2% of patients attending both years consistently miss 3 or more appointments per year. Laboratory monitoring of HIV, that is at least one sampling episode in a year, was achieved, however, in 92-95% of the patients attending each year. The annual number of patients lost to follow-up varied between 7 and 11% per year, but did not change significantly over time, whilst the cumulative number of HIV infected individuals lost to follow-up after 5 years was only 14%. Between 1986 and 1990 self-reported reduction in IDU was more likely in HIV positive than negative individuals; the number of HIV positive individuals who reported injecting for more than 50% of the year fell from 40 to 5% (chi 2(4) = 15.23, p < 0.01) whilst the number who reported at least one injection per year fell from 51 to 23% (chi 2(4) = 62.06, p < 0.001). By comparison amongst non-HIV-infected patients the percentage who reported opiate use for more than 50% of the visits during a year rose from 54% in 1986 to a peak of 70% in 1989 (chi 2(4) = 10.22, p < 0.05) and those who reported opiate use at least once during the year rose from 57% in 1986 to a peak of 75% in 1989 (chi 2(4) = 14.3, p = 0.006). Combined medical and drug clinics from 1986 to 1990 together with a multi-disciplinary team approach to medical care was successful in delivering health care to HIV-infected injection drug users.(ABSTRACT TRUNCATED AT 400 WORDS)
Little is known about the impact of the cancer experience on people following the completion of treatment. Work has begun to outline such experiences primarily in the United States. The purpose of this study was to explore the 'survival' experience within a British context of care, outlining the changes, problems and needs expressed by adult cancer survivors. A convenience sample of 10 adult lymphoma patients from one large teaching hospital was interviewed a minimum of 18 months following the completion of successful treatment. Data were collected by means of tape-recorded semi-structured interviews, using a schedule based on the Cancer Survivorship Questionnaire (Loescher et al., 1990). Data were analysed using content analysis and this indicated that, whilst survival itself may be reward enough for some, others seek to improve or adjust their current status, physically, psychologically or socially. It was concluded that the British cancer survivors were affected in many ways, some having to adjust more than others to the consequences of cure. The preliminary findings pointed towards a notion of 'subtle survivorship' in the British survivors. While they reported many changes in their lives after treatment, many were typically accepting of these and successfully adjusted to their new lives.
Seventeen cases of cleidocranial dysplasia were analysed. On average, there was mandibular prognathism due to increased mandibular length, and a short cranial base. The maxilla was short vertically but not antero-posteriorly. In 13 young subjects followed for an average period of 6 years, more than half of the total number of teeth of each type had not erupted at the normal age, with the exception of mandibular incisors. Twice as many maxillary incisors were delayed compared with those in the lower jaw. Only six of 25 mandibular central incisors were delayed. There was a total of 63 supernumerary teeth in the 13 subjects, mostly occurring in the mandibular premolar and maxillary incisor regions. Many more occurred in the maxillary than in the mandibular incisor region. In the molar regions only six supernumerary teeth were found, five in the upper jaw and one in the lower. Two patients had no supernumerary teeth. One patient showed congenital absence of one mandibular incisor and three premolars.
Use of a health diary has been common in nursing practice settings. Nurses have incorporated the diary as a means of helping clients to document their symptoms and factors which may have precipitated them, often with the aim of modifying particular health behaviours. To date there has been limited exploration of this tool in a nursing research context. Advantages and disadvantages associated with the diary when utilized as a research instrument in health settings are summarized and particular consideration is given to their use in nursing research with cancer patients. Features of the method such as completion and respondent co-operation, format and issues surrounding data analysis are considered. The advantages of this method warrant further exploration in nursing research, despite conflicting and insubstantial evidence regarding the feasibility, validity and reliability of specific kinds of information reported in a diary.
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The study used a randomised controlled trial to find out whether supporting letters from general practitioners accompanying the invitations from a screening centre affected participation in a population-based breast cancer screening program for women aged 50 to 64. A further randomised controlled trial compared the effect of postal reminders with telephone reminders for women who did not respond to an initial invitation to participate in the program. There were 482 women in the first trial and 641 in the second. Excluding women who were ineligible or could not be contacted, participation in screening was 71 per cent in the group which received letters from their general practitioners compared with 62 per cent in the group which did not receive letters (P = 0.059). In the group that received letters, 56 per cent were screened without a reminder compared with 43 per cent of the group that did not receive letters (P = 0.01). Fewer women who received letters from their general practitioners declined the invitation to be screened (P = 0.048). In the second trial, there was no difference in participation between the group receiving telephone reminders and the group receiving postal reminders. As in breast cancer screening programs in other countries, general practitioner endorsement of invitations increased participation in breast cancer screening. Postal reminders were as effective as telephone reminders in encouraging women who did not respond to an initial invitation to participate in screening.
The effect of age on the expression of phosphoenolpyruvate carboxykinase (PEPCK; EC 4.1.1.32) was studied using hepatocytes isolated from 6-, 15-, and 26-mo-old-male Fischer 344 rats fasted for 12 h. The activity of PEPCK in hepatocyte extracts decreased 40-50% (P < 0.05) between 6 and 26 mo of age. The age-related decrease in PEPCK activity was paralleled by a similar decrease (P < 0.05) in the level of PEPCK mRNA. Thus the decrease in PEPCK activity appears to arise from a decrease in level of the PEPCK transcript available for translation. The stability, i.e., half-life of PEPCK mRNA in hepatocytes isolated from 6- and 26-mo-old rats was similar; however, the nuclear transcription of PEPCK by hepatocytes isolated from 26-mo-old rats was 44% lower (P < 0.05) than the nuclear transcription of PEPCK by hepatocytes isolated from 6-mo-old rats. Thus the age-related decline in PEPCK mRNA levels in the liver of fasted rats appears to arise from a decrease in the transcription of PEPCK. A significant decrease (P < 0.05) in the activity and mRNA level of PEPCK also was observed with age in kidney tissue isolated from rats fasted for 12 h.
This study reports the incidence of the various types of cleft lip and/or palate drawn from a regional database of all affected children born in Northern Ireland during the period 1980-1990. The incidence of these anomalies was 1.28 per 1000 live births (1:781). Fifty-three per cent of clefts involved the secondary palate only, 16 per cent the primary palate only, 26 per cent involved both primary and secondary palate, and 5 per cent were unconnected. Overall, more males than females were affected and there were more males than females in the group having complete clefts. Separate clefts of lip and palate occurred exclusively in males with only one exception. Unilateral clefts were more common on the left side. Within the group showing complete unilateral cleft of the primary and secondary palate, left-sided clefts were more commonly male, right-sided clefts were more commonly female. There were no statistically significant sex differences between sides in the unilateral primary palate cleft group.
Studies on the attachment and spreading of cells in culture have provided valuable insights into the mechanisms by which cells transmit information from the outside to the inside of the cell. This brief review considers recent information on the role of focal adhesion-associated protein tyrosine kinases in integrin-regulated cell signalling.
Fifteen patients of mean age 65 years underwent simultaneous coronary artery bypass grafting and abdominal aortic aneurysm repair between 1988 and 1992. Of these 13 had coexistent angina and two had symptomless coronary artery disease detected by preoperative dipyridamole thallium scanning or exercise stress testing. All patients had significant coronary artery disease on coronary angiography. Coronary artery bypass grafting was performed first, with a median number of grafts of 4, a median aortic cross-clamp time of 39 min and a median bypass time of 74 min. Abdominal aortic aneurysm repair followed with a median aortic clamp time of 66 min. Six straight and nine bifurcated grafts were inserted. The median total operating time was 395 min. All patients were managed postoperatively in the cardiothoracic intensive care unit with a median duration of 5 days. The median total hospitalization was 14 days. One patient died of non-cardiac causes; hence the mortality rate was 6.7%. The authors' experience suggests that combined coronary artery bypass grafting and abdominal aortic aneurysm repair is feasible in carefully selected patients.
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Changes in medium free [Ca2+] ([Ca2+]m) (< or = 1 microM) did not affect binding of [3H]InsP3 to inositol 1,4,5-trisphosphate (InsP3) receptors purified from cerebellum, but the chelators normally used to buffer [Ca2+]m inhibited InsP3 binding. 1,2-Bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (BAPTA) (1 mM) fully and reversibly inhibited specific [3H]InsP3 (0.6 nM) binding; the half-maximal effect (IC50) occurred with 0.34 +/- 0.03 mM BAPTA. Similar effects were observed with fura-2 (IC50 = 0.12 +/- 0.03 mM) and EDTA (IC50 = 8.7 +/- 1.9 mM). The order of potency of these Ca2+ chelators in inhibiting InsP3 binding was the reverse of their relative affinities for Ca2+; Ca2+ chelation is not, therefore, the cause of the inhibition. When [Ca2+]m was fixed (250-280 nM), InsP3-stimulated 45Ca2+ mobilization from permeabilized hepatocytes was competitively inhibited by increasing concentrations of BAPTA (KD = 1.8 mM). The effects of BAPTA were not a consequence of chelation of polyvalent cations, because TPEN (0.1 mM), which chelates heavy metal ions, did not affect InsP3 binding and pretreatment of all media with a polymetal sponge (DTPA-polyacrylamide) did not affect the sensitivity of InsP3 binding to BAPTA. We conclude that BAPTA and related Ca2+ chelators, in their Ca2+ -free forms, are competitive antagonists of InsP3 binding to its receptor.
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We have shown that astroglia cultures initiated from newborn mouse neopallium contain microglia progenitor cells. Astroglia secrete growth factor(s) that transform the progenitor cells into microglia. One of the trophic factors is bone marrow macrophage growth factor CSF-1. Mouse embryonic fibroblast cells STO also secrete trophic factor(s) that acts synergistically or additively with CSF-1 on microglia progenitor cells. Using limiting dilution analysis we estimated that in the presence of CSF-1 and STO cells, 1 in every 8 cells in astroglia cultures is a potential microglia progenitor cell.
The effect of aging on the genetic expression of renin was studied in kidney tissue by measuring renin mRNA levels. RNA was isolated from the kidneys of 5- to 37-month-old male C57BL/6J mice. The relative levels of the renin mRNA were measured by dot blot hybridization using a cDNA probe to renin. The size of renin mRNA as determined by northern blot analysis was found to be 1.6 Kb. The size of renin mRNA did not change with increasing age. However, the levels of renin mRNA in kidney RNA decreased 70% after 12 months of age.