Biomedical subjects

C Dean

Publications and source records attributed to C Dean.

At least 163 records · Page 9Linked to original sources

PubMed1989

Expression of a C3 plant Rubisco SSU gene in regenerated C4 Flaveria plants.

We report the successful transformation, via Agrobacterium tumefaciens infection, and regeneration of two species of the genus Flaveria: F. brownii and F. palmeri. We document the expression of a C3 plant gene, an abundantly expressed ribulose 1,5-bisphosphate carboxylase/oxygenase small subunit gene isolated from petunia, in these C4 plants. The organ-specific expression of this petunia gene in Flaveria brownii is qualitatively identical to its endogenous pattern of expression.

DNA↗

PubMed1989

Do psychological factors predict survival in breast cancer?

One hundred and twenty-two women with primary operable breast cancer were interviewed before and three months after mastectomy. The outcome of 121 of the women was assessed 6-8 years after operation. Women who were regarded as having enough symptoms to fulfil the criteria for a psychiatric illness (according to Research Diagnostic Criteria (RDC) and the General Health Questionnaire (GHQ) before operation were less likely to have a recurrence during the follow-up. Those who were assessed three months after operation as coping by using a strategy of denial had a better chance of remaining recurrence-free than those women employing other coping strategies; this finding must be viewed with reservation because of the inherent difficulties in measuring coping strategies. These psychological measures improved the prediction of recurrence-free survival beyond that achieved by other variables (e.g. histological node status, tumour size and treatment).

Adaptation, Psychological↗

PubMed1989

Is puerperal psychosis the same as bipolar manic-depressive disorder? A family study.

The first degree relatives of three groups of women were interviewed; 51 women who had had an illness within two weeks of childbirth and no non-puerperal episodes (the puerperal group), 33 who had puerperal and non-puerperal episodes (the mixed group), and 19 women with bipolar manic-depressive disorder who had non-puerperal episodes only (the manic-depressive group). Over 60% of the affected relatives in all three groups had affective illnesses; in the main these were not puerperal. There were significantly more first degree relatives who had had general practitioner or hospital treatment for psychiatric illness in the puerperal group and in the mixed group than in the manic-depressive group. The puerperal patients had a better prognosis in terms of their illness (number of relapses and time on medication), work functioning and social functioning than the manic-depressive group and the mixed group. The mixed group had an earlier age of onset than the manic-depressive group and the puerperal group. The hypothesis that puerperal psychosis is the same as bipolar manic-depressive disorder was not upheld. The mixed group and the puerperal group were similar with respect to the risk in first degree relatives but differed in terms of prognosis. There were no significant differences between the groups with respect to puerperal episodes in first-degree relatives, although the rate of puerperal psychosis in the first-degree relatives of the puerperal patients was significantly greater than in the general population. The hypothesis that there is a specific genetically determined puerperal psychosis was not supported. Women who had had an illness with an onset within two weeks of childbirth (mixed and puerperal) subsequently had an illness following 36% of their childbirths. In women who had had puerperal and non-puerperal episodes (mixed) the risk was higher; over 50% of deliveries in these women were followed by psychiatric illness.

Adolescent↗

PubMed1989

The contribution of childbearing to the sex difference in first admission rates for affective psychosis.

This epidemiological study examines the contribution of childbearing to the sex difference in first admission rates for affective psychosis. The effects of sex, age, marital status and parity on first admission rates are examined in 114 patients admitted from a defined catchment area. The rate of first admission in females is almost twice that in males. Using logistic regression analysis one significant factor accounting for this sex difference emerges: female parity. The effect of parity is evident up to the age of 54, and it entirely accounts for the sex difference in relative risk. Nonparous females have a lower relative risk of admission than males. An apparent effect of marital status is only significant in females, and is accounted for by parity and age.

Adolescent↗

PubMed1989

Sequences downstream of translation start regulate quantitative expression of two petunia rbcS genes.

We investigated the basis for quantitative differences in leaf expression of the petunia genes (rbcS) encoding the small subunit of ribulose bisphosphate carboxylase. The most abundantly, SSU301, and the most weakly, SSU911, expressed petunia rbcS genes maintained their differential expression when transferred to tobacco, indicating that the determinants of quantitative expression are intrinsic to these rbcS genes. Analysis of chimeric genes in which the sequences of SSU301 and SSU911 had been exchanged at the translation start showed that sequences both 5' and 3' to the start codon contribute to differences in steady-state mRNA levels. The sequences 3' to the translation initiation codon were investigated by preparing chimeric genes in which sequences of the SSU301 and SSU911 were exchanged between each intron and at the translation termination codon. The results showed that sequences downstream of the coding region contribute to quantitative differences in expression of SSU301 and SSU911, and nuclear run-on transcription experiments indicated that the 3' sequences affect transcription rates of the rbcS genes.

Base Sequence↗

PubMed1989

Sequences 5' to translation start regulate expression of petunia rbcS genes.

The promoter sequences that contribute to quantitative differences in expression of the petunia genes (rbcS) encoding the small subunit of ribulose bisphosphate carboxylase have been characterized. The promoter regions of the two most abundantly expressed petunia rbcS genes, SSU301 and SSU611, show sequence similarity not present in other rbcS genes. We investigated the significance of these and other sequences by adding specific regions from the SSU301 promoter (the most strongly expressed gene) to equivalent regions in the SSU911 promoter (the least strongly expressed gene) and assaying the expression of the fusions in transgenic tobacco plants. In this way, we characterized an SSU301 promoter region (either from -285 to -178 or -291 to -204) which, when added to SSU911, in either orientation, increased SSU911 expression 25-fold. This increase was equivalent to that caused by addition of the entire SSU301 5'-flanking region. Replacement of SSU911 promoter sequences between -198 and the start codon with sequences from the equivalent region of SSU301 did not increase SSU911 expression significantly. The -291 to -204 SSU301 promoter fragment contributes significantly to quantitative differences in expression between the petunia rbcS genes.

Base Sequence↗

PubMed1989

Comparative study of carcinoembryonic antigen and epithelial membrane antigen expression in normal colon, adenomas and adenocarcinomas of the colon and rectum.

The heterogeneous nature of tumour antigen expression may require selection of monoclonal antibodies on an individual patient or tumour basis to allow adequate tumour localisation. Carcinoembryonic antigen (CEA) and epithelial membrane antigen (EMA) expression has not previously been compared in colorectal cancer patients. Sections of cancer (n = 52), adjacent normal colon (n = 45), synchronous adenomas (n = 11) and nodal metastases (n = 49) were examined by indirect immunoperoxidase staining in 51 consecutive patients with colorectal cancer using monoclonal antibodies to CEA and EMA. The percentage of cells with positive staining in the primary tumours was graded 1: less than 25%, 2: 25-49%, 3: 50-75%, 4 greater than 75%. All primary colorectal cancers expressed CEA and 43 of 52 expressed EMA (83%). Grading showed CEA greater than EMA in 39, equal in 11 and less in two. Well differentiated cancers were more frequently graded three or four for CEA staining (23 of 27) than moderately differentiated cancers (11 of 22) (p less than 0.01). Equivalent figures for EMA were four of 27 and three of 22 (not significant) (NS) although the majority (86%) were graded 1 and 2. Grade 1 CEA expression was found in six of 15 proximal and only two of 37 distal lesions (p less than 0.01, chi 2 test) while for EMA equivalent figures were three of 15 and six of 37 (NS). Nodal deposits all expressed CEA and 45 of 49 expressed EMA (92%); 29 of 45 normal colon sections showed CEA expression (64%) as did all adenomas. EMA was not expressed by normal colon or adenomas. These results suggest that EMA expression is more specific but less sensitive than CEA for colonic cancer and is independent of tumour differentiation and site. Thus selecting monoclonal antibodies to CEA or EMA based on tumour biopsies may allow improved tumour localisation for imaging or therapy in patents with colorectal cancer.

Adenocarcinoma↗

PubMed1989

Liaison psychiatry in a breast cancer unit.

"The first 50 referrals to a newly established liaison psychiatry service for the breast cancer unit at Guy's Hospital, London, have been examined. The majority of referrals were for psychological reactions to malignant disease; most of these were mood disturbances. Patients with sustained psychological reactions to their malignant disease were more likely to have had treatment for previous psychiatric illness and to lack a confiding relationship compared with those whose psychological reactions were transient. Teaching doctors and nurses to deal effectively with the transient psychological reactions of patients to their malignant disease is an important task of liaison psychiatry."

Breast Neoplasms↗

PubMed1988

Influence of flanking sequences on variability in expression levels of an introduced gene in transgenic tobacco plants.

The petunia rbcS gene SSU301 was introduced into tobacco using Agrobacterium tumefaciens-mediated transformation. The time at which rbcS expression was maximal after transfer of the tobacco plants to the greenhouse was determined. The expression level of the SSU301 gene varied up to 9 fold between individual tobacco plants which had been standardized physiologically as much as possible. The presence of adjacent pUC plasmid sequences did not affect the expression of the SSU301 gene. In an attempt to reduce the between-transformant variability in expression, the SSU301 gene was introduced into tobacco surrounded by 10kb of 5' and 13 kb of 3' DNA sequences which normally flank SSU301 in petunia. The longer flanking regions did not reduce the between-transformant variability of SSU301 gene expression.

Blotting, Northern↗

PubMed1988

Expression of tandem gene fusions in transgenic tobacco plants.

We have studied the expression of four sets of tandem gene fusions in transgenic tobacco plants. This was to determine if the problem of between-transformant variability in expression of introduced genes could be overcome by using a linked reference gene as a co-ordinately expressed control. Tandem gene fusions containing identical 5' flanking regions (SSU301-ocs with either SSU301-cat or SSU301-SSU911) were not co-ordinately expressed in the transgenic tobacco plants whereas the tandem gene fusions containing similar but not identical 5' flanking regions (SSU301-ocs with SSU911-cat or SSU911-SSU301) were co-ordinately expressed. The lack of co-ordinate expression of some of the tandem gene fusions appears to be partially explained by absence of the corresponding genomic DNA segments in the transgenic plants.

Gene Expression Regulation↗

PubMed1988

A comparison of carcinoembryonic antigen (CEA) and epithelial membrane antigen (EMA) in human colorectal cancer.

The development of monoclonal antibodies (MAbs) to tumour-associated antigens has allowed the successful radioimmunolocalization of a variety of tumours and has provided a basis for targeted therapy. In patients with colorectal cancer, antibodies to CEA have been the most widely used for imaging, but their role in targeted therapy may be inhibited by their reaction with normal tissues and with circulating CEA. Epithelial-membrane antigen (EMA) is expressed by most epithelial tumours, including colorectal cancers, and antibodies to EMA may provide a satisfactory alternative. We therefore compared two high-affinity MAbs, one to CEA (C46) and one to EMA (ICR2), in tissues obtained from 31 patients with cancer (18 primary colonic, 6 nodal metastases and 7 liver metastases), 14 patients with adenomatous polyps and 17 with normal colon. The indirect immunoperoxidase staining reaction was used and the results classified as either positive or negative. A heterogeneous pattern of staining was found for both antibodies. ICR2, the anti-EMA, reacted with slightly fewer colonic cancers than C46, the anti-CEA antibody (83% vs. 100%) and a similar number of metastases. Most noticeable was the minimal reaction of anti-EMA with normal colon (12% vs. 71%) and benign polyps (7% vs. 79%) in comparison to anti-CEA. This would suggest a possible role for ICR2 in the radioimmunolocalization and targeting of colorectal cancer.

Antigens, Neoplasm↗

PubMed1988

The emotional impact of mastectomy.

Over the last few decades the psychosocial problems following mastectomy have become well recognized and surgical treatment for breast cancer has become less mutilating. For women with small cancers a number of equally effective treatments are available and involving the patient in the choice of treatment appears to reduce morbidity.

Affective Symptoms↗

PubMed1987

Effect of the 1983 Mental Health Act on the management of psychiatric patients.

Two principal objectives of the 1983 Mental Health Act were to decrease the use of emergency orders and to give patients on observation orders the right of appeal. Statistics were collected from the 13 hospitals that admit acute psychiatric patients in the Greater Manchester area, and the figures for 1980-1 were compared with those for 1984-5. Changes in use of the different sections were examined in university units, large psychiatric hospitals, and district general hospital units. The use of emergency orders decreased and the use of treatment orders increased; the use of observation orders remained unchanged. Many more patients exercised their right of appeal in 1984-5, but the number discharged by tribunals remained small. The nurses' holding power was used infrequently. The different types of hospital are now more concordant in their use of these orders than before the 1983 act.

Commitment of Persons with Psychiatric Disorders↗

PubMed1987

Confirmation of the relative expression levels of the Petunia (Mitchell) rbcS genes.

We have mapped the transcription start sites of three petunia rbcS genes and reassayed the relative expression levels of the petunia rbcS genes using the technique of primer extension. This analysis was performed specifically to address the confusion in the literature concerning the relative expression levels of the two petunia rbcS genes, SSU301 and SSU11A. The primer extension analysis reported here confirms our previous results, specifically that the rbcS gene, which we term SSU301, gives significantly higher levels of steady state RNA than any of the other rbcS genes in leaf tissue from 10 week old petunia plants.

Base Sequence↗

PubMed1987

Psychiatric morbidity following mastectomy: preoperative predictors and types of illness.

One hundred and twenty-two women with primary operable breast cancer were interviewed before, 3 months after and 12 months after mastectomy. Twenty-six percent of women had psychiatric symptoms 12 months after operation which justified a research diagnostic criteria diagnosis but most of the illnesses were mild; only 5% of women were regarded as being psychiatrically ill by a psychiatrist. The patients psychiatric state preoperatively, the treatment package received by the patient and the patient's marital relationship were related to psychiatric outcome three months after operation. The patient's psychiatric state preoperatively, her marital status, social class and menopausal status were all predictors of psychiatric outcome 12 months after operation. These results are discussed in terms of the practical way in which women at risk of psychiatric illness postmastectomy could be identified preoperatively by a nurse counsellor.

Adult↗

PubMed1987

Benign juvenile myoclonic epilepsy.

Two patients with long-standing, poorly controlled seizures presented to a university hospital emergency department. Both patients had myoclonic jerks on waking and evidence of absence seizures as well as generalized tonic-clonic seizures. A diagnosis of benign juvenile myoclonic epilepsy was made, and the seizures were controlled with valproic acid.

Adolescent↗

PubMed1987

Cardiac, respiratory, and renal responses to stimulation of the external cuneate nucleus.

The cardiac, respiratory, and renal responses of electrical stimulation and microinjection of excitatory amino acids into the external cuneate nucleus were investigated in 57 cats anesthetized with pentobarbital sodium, paralyzed, and artificially ventilated. Trains of rectangular cathodal pulses of 40-100 microA at 50 Hz and 0.1 ms duration were delivered through monopolar glass microelectrodes with a tip diameter of 10-20 micron, filled with indium-Woods metal alloy. Electrical stimulation at 232 histologically identified sites within the external cuneate nucleus could evoke changes in arterial blood pressure, heart rate, and efferent renal sympathetic nerve activity. In a further set of experiments, a change in respiration was observed at 74 identified sites. An increase or decrease in all parameters measured could be elicited at different stimulus sites within the external cuneate nucleus. Repositioning of the electrode (0.2-0.4 mm) in depth or laterally could result in a different response with stimulation. Microinjections of D,L-homocysteic acid or glutamate could mimic the evoked changes in blood pressure, heart rate, efferent renal sympathetic nerve activity, and respiration. This suggests that the external cuneate nucleus contains cell bodies that may modulate components of various cardiac, respiratory and renal reflexes. It is proposed that the external cuneate nucleus may be involved in the integration of somato-autonomic reflex responses.

Animals↗

PubMed1986

Discharge patterns in postganglionic neurones to skeletal muscle and kidney during activation of the hypothalamic and midbrain defence areas in the cat.

Electrical stimulation of hypothalamic and midbrain defence area sites eliciting a cholinergic vasodilatation in the hindlimb activates vasodilator fibres supplying skeletal muscle. Simultaneous baroreceptor mediated suppression of sympathetic vasoconstrictor activity to the muscle and postfiring depression of vasoconstrictor activity contribute to the development of the vasodilatation during and after the stimulus. The observation of a differential pattern of activation of muscle and renal vasoconstrictor fibres implies a reciprocal influence exerted on these sympathetic outflows by neurones in the defence areas of the brain.

Aggression↗