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M James

Publications and source records attributed to M James.

At least 145 records · Page 8Linked to original sources
PubMed1990

Gene mapping.

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Chromosome Mapping↗
PubMed1990

Constraints in simian virus 40 (SV40) encapsidation, as determined by SV40-based shuttle viruses.

Simian virus 40 (SV40)-based shuttle vectors, containing the SV40 late genes, can be packaged as infectious pseudovirions. In terms of their function as bacterial plasmids, modifications in the overall size of these plasmids can be tolerated within a very wide range, which has allowed us to determine the requirements for SV40 encapsidation, free of the more stringent limitations of SV40 virus. Monkey COS7 cells were transfected with over- and undersized SV40-based shuttle virus plasmids and their progeny have been analysed to follow the stability and evolution of these genomes. Two of the three plasmids analysed undergo recombination, generating molecules with sizes of between 4.0 and to 4.8 kb which were selected after multiple lytic cycles. This size range may correspond to the DNA lengths preferentially packaged in SV40 capsids. The structure of the rearranged plasmids indicates that there is a strong selective pressure for genomes that retain the functions necessary for replication and virus production. Depending on the parent DNA, two main classes of rearrangements were generated: duplications in tandem with the SV40 origin of replication and deletions. Both classes are probably a result of selective size and replicative advantages, which are then biologically amplified during plasmid transmission as virus particles.

Animals↗
PubMed1990

Risk factors of female HIV-seropositive patients attending the clinic for sexually transmitted diseases at St Mary's Hospital, London.

Of 3450 women tested for antibodies to human immunodeficiency virus HIV-1 and HIV-2 between September 1985 and July 1989, 61 were positive (1.8%). Twenty-seven of these (44%) were presumed to have acquired their HIV infection by heterosexual contact and 23 (38%) were intravenous drug addicts. In geographical origin, 23 (38%) of the patients were from the UK and 19 (31%) from Africa. Amongst these 61 women, 2 (3%) have since died, one committed suicide and one was suspected of committing suicide.

Adolescent↗
PubMed1989

Localization of the cryptdin locus on mouse chromosome 8.

Cryptdin is a defensin-related peptide, and its mRNA accumulates to high abundance in epithelial cells of intestinal crypts beginning in the second week of postnatal development. The cryptdin (Defcr) locus was assigned to mouse chromosome 8 by Southern blotting of DNAs from mouse/hamster somatic hybrid cell lines. Analysis of somatic hybrid DNAs for mouse-specific restriction fragments showed zero discordance and perfect concordance with chromosome 8. The Defcr locus was localized on chromosome 8 by analysis of DNAs from recombinant inbred (RI) strains of mice after identification of three potential Defcr alleles based on restriction fragment length polymorphisms (RFLPs) in inbred strains. The strain distribution patterns of the Defcr locus were compared with those of chromosome 8 markers in five panels of RI strains. Analysis of cosegregation of Defcr with xenotropic proviral locus Xmv-26 and additional loci confirmed the chromosomal assignment and showed that Defcr is on proximal chromosome 8 within approximately 6 (1.3 to 21.3) cM of Xmv-26. The mouse Defcr locus and the human defensin gene(s) located on chromosome 8p23 appear to map to homologous regions.

Adrenocorticotropic Hormone↗
PubMed1989

Developmental regulation of cryptdin, a corticostatin/defensin precursor mRNA in mouse small intestinal crypt epithelium.

Cryptdin mRNA codes for the apparent precursor to a corticostatin/defensin-related peptide that accumulates to high levels in mouse intestinal crypt epithelium during postnatal development. The primary structure, intestinal cell distribution, and developmental appearance of cryptdin mRNA have been determined. Cryptdin mRNA is 450-480 nucleotides long. Translation of the partial cryptdin cDNA sequence reveals a 70-amino acid open reading frame that includes 32 carboxy-terminal residues that align with those in the consensus sequence, C.CR...C....ER..G.C....CCR, which is a common feature of leukocyte defensins and lung corticostatins (Selsted, M. E., D. M. Brown, R. J. DeLange, S. S. L. Harwig, and R. I. Lehrer. 1985. J. Biol. Chem. 260:4579-4584; Zhu, Q., J. Hu, S. Mulay, F. Esch, S. Shimasaki, and S. Solomon. 1988. Proc. Natl. Acad. Sci. USA. 85:592-596). In situ hybridization of cryptdin cDNA to paraformaldehyde-fixed, frozen sections of adult jejunum and ileum showed intense and specific labeling of epithelial cells in the base of all crypts. Analysis of sections from suckling mice showed that cryptdin mRNA is detectable in 10-20% of crypts in 10-d-old mice, in approximately 80% of crypts in 16-d-old mice, and in all crypts of mice 20 d and older. During the fourth week, the sequence accumulates in crypts to the maximal adult level. Cryptdin mRNA content in adult small intestine is independent both of T cell involvement and luminal bacteria. The role of cryptdin in small bowel physiology remains to be determined: cryptdin may inhibit bacterial translocation, modulate intestinal hormone synthesis, influence hormonal sensitivity of the intestinal epithelium, or exhibit a multiplicity of related activities.

Aging↗
PubMed1988

Visual apperceptive agnosia: a clinico-anatomical study of three cases.

The visuo-perceptual abilities of three cases with unilateral lesions of the right hemisphere selected on the basis of the co-occurrence of impaired performance on a test of visual object perception and normal performance on a test of shape discrimination are reported. Their performance was also impaired on other tests of visual object recognition in which the perceptual difficulty of the task was manipulated by obscuring the salient features of the representation. At the same time it was found that on a variety of other tests of visual-sensory processing their performance was entirely normal, as was their performance on tests of visual semantic knowledge, tests that were failed by a patient with a visual associative agnosia. It is argued that this syndrome has all the hallmarks of an apperceptive agnosia, a failure of perceptual categorisation in which the physical identity of the object is specified. The two discontinuities between visual-sensory processing, perceptual categorisation and visual-semantic processing are discussed in terms of a 2 categorical stage model of object recognition.

Aged↗
PubMed1987

Psychosocial aspects of Mexican-American, white, and black teenage pregnancy.

This study assesses whether pregnant Mexican-American adolescents have psychosocial characteristics different from their pregnant white or black peers. The study population consisted of 199 consecutive Mexican-American, white, and black pregnant adolescents, ages 11-19 years, followed prospectively at the University of California San Diego Medical Center Teen Obstetric Clinic from 1978 to 1981 (79 whites, 76 Mexican-Americans, and 44 blacks). Although all three groups had the same chronologic age (X = 16.4 +/- 1.4 years), and the same number of years of schooling, pregnant black adolescents were more likely to be in school at the time of registration for prenatal care (p less than 0.01). Mexican-American teens were more likely to be married at conception and/or delivery (p less than 0.001), and to breastfeed their infants (p less than 0.05). The fathers of the Mexican-American babies were more likely than other fathers to be full-time students or employed (p less than 0.001). Although pregnant Mexican-American teens came from the largest families (p less than 0.001), black teenagers most frequently reported a good mother-daughter relationship (p less than 0.05). White pregnant teens most frequently reported a family history of psychiatric illness (p less than 0.01), parental death (p less than 0.05), or runaway behavior (p less than 0.01). These data suggest that pregnant teenagers from these three racial/ethnic backgrounds have different psychosocial profiles and hence different psychosocial problems and needs.

Adolescent↗
PubMed1987

Screening for psychiatric morbidity. The pattern of psychological illness and premorbid characteristics in four chronic pain populations.

Three hundred and seventy-eight patients from 4 chronic pain populations have been examined by self-assessment questionnaire methods to estimate the amount of psychiatric morbidity present. Using the General Health Questionnaire-28 scaled version (GHQ-28) the findings for probable psychiatric illness by clinic were: for anaesthetists' pain clinics serving a mixed urban and rural population--37%; for an oral medicine facial pain clinic--30%; for a rural hospital pain clinic--37%; and for a psychiatrists' pain assessment and treatment service--51%. These findings demonstrate the effects of selection upon the psychiatric characteristics of different pain populations. On the subscales of the General Health Questionnaire the psychiatric clinic patients were significantly more depressed than those in the other 3 groups (P less than 0.001) and also showed more social dysfunction (P less than 0.001). On the Irritability/Depression and Anxiety Questionnaire (IDA), depression and inward irritability were higher in the psychiatric clinic patients (P less than 0.001) but the amount of anxiety did not differ by clinic or by diagnosis (P greater than 0.05). These findings are taken to indicate that the extent of somatic complaints and anxiety does not differentiate the majority of pain patients in pain services with psychological illness from others attending for treatment. However, in the patients who have definite psychological symptoms, depression, social dysfunction and irritability provide a characteristic pattern. The psychiatric clinic patients were demonstrably more introverted or obessional on the Hysteroid/Obsessoid Questionnaire (HOQ) than those in other clinics. Childhood experience as seen by the patients did not differ by clinic or diagnosis and did not correlate significantly with personality as measured by the HOQ. It did correlate very significantly with measures of the current mood represented by the IDA. This effect was relatively weak, permitting the inference that the major portion of those psychological abnormalities which were found to be present was related to other factors such as the occurrence of painful lesions.

Adult↗
PubMed1987

The influence of linoleate and vitamin E from sunflower seed oil on platelet function and prostaglandin production in the common marmoset monkey.

Vitamin E and linoleate, both of which are found in high concentrations in sunflower seed oil, were examined independently for their influence on general and blood-vascular parameters in vitamin E-deficient common marmosets. A vitamin E-deficient diet (-E, 4 micrograms/g) was supplemented with either 40 micrograms/g vitamin E (+E), vitamin E stripped sunflower oil (+10% SSO-E), or SSO (+10% SSO w/w) in a 2 x 2 factorial designed experiment, and the diets fed for 9 months to 4 even groups of common marmosets. Vitamin E deficiency was associated in marmosets with a loss of skeletal muscle mass and of body weight, enhanced peroxidative haemolysis of erythrocytes, increased white blood cell counts, and in the SSO-E group a relative neutrophilia. Platelet reactivity was increased with vitamin E deficiency, and to a greater degree with the SSO-E group. Aortic prostacyclin production was significantly increased by the addition of vitamin E, linoleate and both as SSO to the deficient diet, the effects being additive. Fatty acid changes associated with the different treatments reflected the influence of high linoleate and vitamin E treatments. The platelet and aortic arachidonate value in the SSO-E group showed the lowest and most variable value, and this was associated with greatest platelet aggregability. An adequate vitamin E intake is essential for stabilising high PUFA diets and biomembranes and enhancing the protective role of prostacyclin in blood vessels against thrombogenesis.

Animals↗