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Biomedical subjects

P Jones

Publications and source records attributed to P Jones.

At least 217 records · Page 12Linked to original sources
PubMed1996

Susceptibility to multiple cutaneous basal cell carcinomas: significant interactions between glutathione S-transferase GSTM1 genotypes, skin type and male gender.

The factors that determine development of single and multiple primary cutaneous basal cell carcinomas (BCCs) are unclear. We describe a case-control study firstly, to examine the influence of allelism at the glutathione S-transferase GSTM1 and GSTT1 and cytochrome P450 CYP2D6 loci on susceptibility to these tumours and, secondly, to identify interactions between genotypes and relevant individual characteristics, such as skin type and gender. Frequency distributions for GSTM1 genotypes in cases and controls were not different, although the frequency of GSTM1 A/B was significantly lower (P = 0.048) in the multiple BCCs than in controls. We found no significant differences in the frequencies of GSTT1 and CYP2D6 genotypes in cases and controls. Interactions between genotypes were studied by comparing multinomial frequency distributions in mutually exclusive groups. These identified no differences between cases and controls for combinations of the putatively high risk GSTM1 null, GSTT1 null, CYP2D6 EM genotypes. Interactions between GSTM1 A/B and the CYP2D6 PM and GSTT1-positive genotypes were also not different. Frequency distributions of GSTM1 A/B with CYP2D6 EM in controls and multiple BCCs were significantly different (P = 0.033). The proportion of males in the multiple BCC group (61.3%) was greater than in controls (47.0%) and single BCC (52.2%), and the frequency of the combination GSTM1 null/male gender was significantly greater in patients with multiple tumours (P = 0.002). Frequency distributions of GSTM1 null/skin type 1 were also significantly different (P = 0.029) and the proportion of subjects who were GSTM1 null with skin type 1 was greater (P = 0.009) in the multiple BCC group. We examined the data for interactions between GSTM1 null/skin type 1/male gender by comparing frequency distributions of these factors in the single and multiple BCC groups. The distributions were almost significantly different (exact P = 0.051). No significant interactions between GSTT1 null or CYP2D6 EM and skin type 1 were identified. Comparisons of frequency distributions of smoking with the GSTM1 null, GSTT1 null and CYP2D6 EM genotypes identified no differences between patients with single and multiple tumours.

Aged↗
PubMed1996

Humans, information and science.

The use of information forms the basis of nursing policies, standards and professional codes of conduct. Although used intuitively, nurses must now also grapple empirically with information needs often defined by others, and with the technology used to capture and process it. Even the briefest contemplation of 'information' reveals a truly pervasive concept. Information is ubiquitous. In order to care effectively in the so-called 'information age' health care professionals need to understand information. This paper is a small contribution to that effort, attempting to conjoin the disparate fields of health and the information sciences; and the basic sciences upon which they are based. This paper explores how definitions of information formulated in computing and communication theory relate to health and other aspects of human experience. The strategy adopted to achieve this is threefold. First, there is the vexed question of defining data, information and knowledge. Second, I consider how communication--that essential nursing activity--relates to information, meaning and the messages people seek to convey to each other. Thirdly, clinical situations are described in an information-oriented manner, using the concepts of 'redundancy' and 'entropy'. The conclusion provides an historical perspective.

Communication↗
PubMed1996

Metabolism of [U-13C5] glutamine in cultured astrocytes studied by NMR spectroscopy: first evidence of astrocytic pyruvate recycling.

Metabolism of [U-13C5]glutamine was studied in primary cultures of cerebral cortical astrocytes in the presence or absence of extracellular glutamate. Perchloric acid extracts of the cells as well as redissolved lyophilized media were subjected to nuclear magnetic resonance and mass spectrometry to identify 13C-labeled metabolites. Label from glutamine was found in glutamate and to a lesser extent in lactate and alanine. In the presence of unlabeled glutamate, label was also observed in aspartate. It could be clearly demonstrated that some [U-13C5]glutamine is metabolized through the tricarboxylic acid cycle, although to a much smaller extent than previously shown for [U-13C5]glutamate. Lactate formation from tricarboxylic acid cycle intermediates has previously been demonstrated. It has, however, not been demonstrated that pyruvate, formed from glutamate or glutamine, may reenter the tricarboxylic acid cycle after conversion to acetyl-CoA. The present work demonstrates that this pathway is active, because [4,5-13C2]glutamate was observed in astrocytes incubated with [U-13C5]-glutamine in the additional presence of unlabeled glutamate. Furthermore, using mass spectrometry, mono-labeled alanine, glutamate, and glutamine were detected. This isotopomer could be derived via the action of pyruvate carboxylase using 13CO2 produced within the mitochondria or from labeled intermediates that had stayed in the tricarboxylic acid cycle for more than one turn.

Alanine↗
PubMed1996

Glutathione S-transferase GSTT1 genotypes and susceptibility to cancer: studies of interactions with GSTM1 in lung, oral, gastric and colorectal cancers.

Allelism in glutathione S-transferase GSTM1 and GSTT1 has been suggested as a risk factor in various cancers. Accordingly, we describe a group of case-control studies carried out to identify associations between GSTT1 genotypes and susceptibility to lung, oral, gastric and colorectal cancers. The frequencies of the putatively high risk GSTT1 null genotype were not increased in the lung, oral or gastric cancer cases compared with controls but the frequency of this genotype was significantly increased (P = 0.0011, odds ratio = 1.88) in the colorectal cancer cases. No significant interactions between the GSTT1 and GSTM1 null genotypes types were identified in the cancer groups studied. Indeed, no significant associations between GSTM1 genotypes and susceptibility were identified though further evidence was obtained that the protective effect of GSTM1*A and GSTM1*B is not equal. The data complement studies showing that GSTT1 null is associated with an increased susceptibility to total ulcerative colitis and suggests that this enzyme is important in the detoxification of unidentified xenobiotics in the large intestine.

Case-Control Studies↗
PubMed1996

Prenatal exposure to influenza and increased cerebrospinal fluid spaces in schizophrenia.

Several epidemiological studies have suggested that maternal exposure to influenza during midgestation is a risk factor for schizophrenia. In exploring the possible pathogenic mechanism, we examined the relationship between computed tomography structural brain measures in 83 schizophrenia patients and 113 controls and also their risk of maternal exposure to influenza. Four brain measures of the cerebrospinal fluid (CSF) spaces (lateral ventricle, maximum third ventricle, sulcal fluid, and sylvian fissure) were investigated in relation to the risk exposure level. In schizophrenia patients, these measures, in particular sylvian fissures, were found to increase with higher levels of risk exposure to influenza during the susceptible period (i.e., midgestation); no such effect was found in controls. These results indicate that risk for midgestational influenza exposure is associated with generalized enlargement of the CSF spaces, especially in the region of the temporal lobe. The findings suggest that certain morphological abnormalities of the brain frequently reported in schizophrenia patients may be partly attributable to antenatal exposure to influenza.

Adult↗
PubMed1996

Schizophrenia.

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Age Factors↗
PubMed1996

Does familiality predispose to both emergence and persistence of psychosis? A follow-up study.

BACKGROUND: It as been suggested that in schizophrenia an association exists between family history of schizophrenia and poor outcome on the one hand, and family history of affective disorders and good outcome on the other. METHOD: We tested for associations between four-year outcome and familial loading for psychotic disorders in a mixed sample of 150 consecutively admitted patients with functional psychosis (schizophrenia, psychotic affective disorders, other psychotic disorders) of recent onset. For each proband, a familial loading score for (i) broadly defined psychotic disorder, (ii) schizophrenia, and (iii) affective disorder was calculated using information on relatives obtained through the Family History Research Diagnostic Criteria method and direct interviews of relatives with the Schedule for Affective Disorders and Schizophrenia. RESULTS: In our sample of psychotic patients, familial loading for psychotic disorder predicted persistent negative symptoms over the follow-up period (OR 1.5; 95% CI 1-2.2), especially in schizophrenia, and was also associated with more time hospitalised (P < 0.05) [corrected], and more social disability at follow-up (P < 0.05). Greater familial loading for schizophrenia predicted a greater likelihood of non-recovery (OR 2.2; 95% CI 1.1-4.4) and a greater likelihood to have had persistent negative symptoms over the follow-up period (OR 1.7; 95% CI 0.9-3.1). No association was found between outcome and familial loading for affective disorder. CONCLUSIONS: We conclude that familial loading may be a continuous risk factor for some dimensions of clinical outcome in the functional psychoses. This suggests that there is a continuum of genetic liability not only to the emergence of psychotic illness, but also the subsequent chronicity of the disorder.

Adolescent↗
PubMed1996

Unwantedness of a pregnancy and schizophrenia in the child.

BACKGROUND: Maternal stress during pregnancy has been suggested as a risk factor for schizophrenia. We tested the hypothesis that being the child of an unwanted pregnancy would be associated with later schizophrenia. METHODS: Data were collected prospectively in the Northern Finland 1966 Birth Cohort of 11 017 individuals. In the sixth or seventh month of pregnancy mothers were asked whether the pregnancy was wanted, mistimed but wanted or unwanted. Schizophrenia diagnoses in the cohort members were obtained from the Finnish Hospital Discharge Register. RESULTS: Seventy-six cases of DSM-III-R schizophrenia were identified in the whole cohort between the ages of 16 and 28 years; a cumulative incidence of 0.7%, compared with 1.5% for those born from unwanted pregnancies. The risk of later schizophrenia among unwanted children was raised compared with wanted or mistimed children, even after adjustment for confounding by sociodemographic, pregnancy and perinatal variables (OR 2.4; 95% CI 1.2-4.8). CONCLUSIONS: The results suggest that unwantedness may operate either directly as a psychosocial stress during development making children more liable to schizophrenia, or it may be a marker for behaviours associated with risk in either the mother or the child.

Adolescent↗
PubMed1996

A look up the scope.

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Delivery of Health Care↗
PubMed1995

Psychosis with good prognosis in Afro-Caribbean people now living in the United Kingdom.

OBJECTIVES: To compare the course and outcome of psychotic illness in a group of Afro-Caribbean patients resident in the United Kingdom and a group of white British patients. DESIGN: Cohort study of consecutive admissions followed up for four years. SUBJECTS: 113 patients with psychotic illness of recent onset admitted to two south London hospitals. MAIN OUTCOME MEASURES: Course of illness, history of self harm, social disability, treatment received, and hospital use adjusted for socioeconomic origin. RESULTS: The Afro-Caribbean group spent more time in a recovered state during the follow up period (adjusted odds ratio 5.0; 95% confidence interval 1.7 to 14.5), were less likely to have had a continuous illness (0.3; 0.1 to 0.8), were less at risk of self harm (0.2; 0.1 to 0.8), and were less likely to have been prescribed antidepressant treatment (0.3; 0.1 to 0.9). There were no differences in hospital use, but the Afro-Caribbean group had more involuntary admissions (8.9; 2.1 to 35.6) and more imprisonments over the follow up period (9.2; 1.6 to 52.3). CONCLUSIONS: Afro-Caribbean patients in the United Kingdom have a better outcome after psychiatric illness than do white people. The combination of high incidence and more benign course of illness of psychotic illness in this group may be due, at least in part, to a greater exposure to precipitants in the social environment.

Adolescent↗
PubMed1995

Susceptibility to astrocytoma and meningioma: influence of allelism at glutathione S-transferase (GSTT1 and GSTM1) and cytochrome P-450 (CYP2D6) loci.

We describe a case-control study to identify associations between polymorphism at the cytochrome P-450 (CYP2D6) and glutathione S-transferase (GSTT1 and GSTM1) loci and susceptibility to astrocytoma and meningioma. Accordingly, genotype frequencies in 112 astrocytoma and 50 meningioma patients were compared with frequencies in 577 controls. GSTM1 genotype frequencies in these groups were not different. Logistic regression analysis showed GSTT1 null and CYP2D6 poor metabolizer were risk factors in astrocytoma (odds ratio = 2.67 P = 0.0005 and odds ratio = 4.17 P = 0.0043, respectively) and meningioma (odds ratio = 4.52, P = 0.0001 and odds ratio = 4.90, P = 0.0132, respectively) when corrected for the other variables. No interactive effects between genotypes were identified. The data suggest polymorphism at loci encoding carcinogen-metabolizing enzymes influences susceptibility to astrocytoma and meningioma, possibly by determining effectiveness in the detoxification of environmental carcinogens.

Adult↗