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J Pearson

Publications and source records attributed to J Pearson.

At least 19 recordsLinked to original sources
PubMed2006

Measurement of the Ec.m. = 184 keV resonance strength in the 26gAl (p, gamma)27 Si reaction.

The strength of the Ec.m. = 184 keV resonance in the 26gAl(p, gamma)27 reaction has been measured in inverse kinematics using the DRAGON recoil separator at TRIUMF's ISAC facility. We measure a value of omega gamma = 35 +/- 7 microeV and a resonance energy of Ec.m. = 184 +/- 1 keV, consistent with p-wave proton capture into the 7652(3) keV state in 27Si, and discuss the implications of these values for 26GAl nucleosynthesis in typical oxygen-neon white-dwarf novae.

Journal Article↗
PubMed2006

Effect of different forms of information produced for cancer patients on their use of the information, social support, and anxiety: randomised trial.

OBJECTIVE: To explore the hypothesis that different methods of selecting and printing information for cancer patients could improve emotional support by affecting interaction with others, and so lead to improved psychological wellbeing. DESIGN: Randomised trial with eight groups (three factors, 2x2x2). Data collected at recruitment and three month follow-up. PARTICIPANTS: 400 patients starting radiotherapy, of whom 325 with breast or prostate cancer and complete anxiety and depression data were included in the analysis. INTERVENTIONS: Printed booklets: half had only general information from CancerBACUP about each patient's cancer and half had personalised information from the patient's medical record plus selected general information; half were composed of information chosen interactively by the patient and half were produced automatically with a larger volume of material; and half had additional advice on anxiety management and half did not. MAIN OUTCOME MEASURES: Patients' views of the information, use of their booklets with others; change in reported social support; change in anxiety and depression. RESULTS: The larger booklets produced automatically were more likely to be found useful and to tell patients something new and less likely to be seen as too limited than the booklets produced interactively, but they were also more likely to overwhelm some patients. Personalised booklets were more likely than general booklets to tell patients something new. There was no difference in patients' perceived understanding of their cancer by any of the intervention factors. Patients with personalised information were more likely to show their booklets to others and to think it helped in discussing their cancer or its treatment. There were no major differences in social support, anxiety, or depression by any intervention factors. CONCLUSIONS: Patients were more likely to show personalised information to their confidants than general information. Further research is needed into the effects of sharing information on patients' social support and anxiety. Trial registration US Government Clinical Trials Database NCT00127465.

Adult↗
PubMed2006

Genetic dissection of a stem cell niche: the case of the Drosophila ovary.

In this work, we demonstrate a powerful new tool for the manipulation of the stromal component of a well-established Drosophila stem cell niche. We have generated a bric-a-brac 1 (bab1)-Gal4 line that drives UAS expression in many somatic ovary cell types from early larval stages. Using this Gal4 line, we could effectively induce FLP/FRT-mediated recombination in the stromal cells of the ovarian germline stem cell niche. Mutant clones were observed in the developing ovary of larvae and pupae, including in somatic cell types that do not divide in the adult, such as the cap cells and the terminal filament cells. Exploiting the ability of bab1-Gal4 to generate large clones, we demonstrate that bab1-Gal4 is an effective tool for analyzing stem cell niche morphogenesis and cyst formation in the germarium. We have identified a novel requirement for engrailed in the correct organization of the terminal filaments. We also demonstrate an involvement for integrins in cyst formation and follicle cell encapsulation. Finally using bab1-Gal4 in conjunction with the Gal80 system, we show that while ectopic dpp expression from stromal cells is sufficient to induce hyperplastic stem cell growth, neither activation nor inactivation of the BMP pathway within stromal cells affects germline stem cell maintenance.

Animals↗
PubMed2006

Donor exclusion in the National Blood Service Tissue Services living bone donor programme.

National Blood Service (NBS) Tissue Services (TS) operates living donor and deceased donor tissue banking programmes. The living bone donor programme operates in collaboration with 91 orthopaedic departments across the country and collects bone donations, in the form of surgically removed femoral heads (FHs), from over 5,000 patients per annum undergoing total hip replacement. Bone donated via the living programme constitutes approximately 55% of the total bone donated to NBS. Non-NBS tissue banks, primarily in hospital orthopaedic departments, also bank donated bone for the UK. A survey of information received from 16 collaborating orthopaedic centres, between April 2003 and August 2004, identified 709 excluded donors. The total number of donations banked from these sites was 1,538. Donations can be excluded before collection if there are contraindications noted in a potential donor's medical history before their operation. Donors may also be excluded after collection of the FH, for instance because of reactive microbiology tests for blood borne viruses, or if the donation storage conditions or related documentation have not met stringent quality requirements. In this survey, bone or joint conditions were the major reasons for excluding potential donors before donation (154 of 709 exclusions, 22%), followed by a current or a past history of malignancy (139 of 709 exclusions, 20%). Local staffing and operational difficulties sometimes resulted in potential donors being missed, or specific reasons for exclusion not being reported (117 exclusions). These out numbered exclusions due to patient refusal (80 exclusions). A small number (< 5) appear to have been excluded erroneously. There was considerable local variation in the reasons given for exclusion and certainly under-reporting. A survey of donations discarded after collection in the same period highlighted that 43% were donor related; 110 of 370 did not provide a follow-up blood sample. More than 30% were due to delays in forwarding blood samples to the microbiological laboratory for testing, resulting in deterioration of the sample quality. Training to ensure that standards are complied with and a firm evidence base for exclusion criteria, applied uniformly, will help focus donor identification efforts on individuals meeting rational criteria so that fewer potential donations are lost.

Bone Banks↗
PubMed2006

Knowledge of and attitudes towards resuscitation in New Zealand high-school students.

BACKGROUND: Introducing cardiopulmonary resuscitation (CPR) training in the high-school curriculum has been widely recommended as a long-term strategy to educate the wider community. Although CPR has been included in the New Zealand school curriculum, it is listed as an optional subject only. AIM: To assess the attitude towards and knowledge of CPR in 16-17-year-old high-school students in New Zealand. METHODS: Questionnaires were administered to 494 students aged 16-17 years across six high schools in Wellington, New Zealand. Both knowledge and attitude were evaluated in the questionnaire. RESULTS: Students showed poor theoretical knowledge, with a mean (SD) score of 5.61 (2.61) out of a maximum score of 18. Although there was no difference between male and female students, those who had received previous first-aid training (70%) showed greater knowledge (6.04 (2.56)) than their untrained counterparts (4.91 (2.24); p = 0.001). Those students with a positive attitude towards CPR and first-aid training (63%) acquired a higher knowledge score (6.12 (2.4)) than those with a negative attitude (17%; 4.65 (2.5); p = 0.001). Students with negative associations were also less likely to want to learn more about CPR and first aid (11%) when compared with those with positive associations (92%), and indicated less willingness to perform CPR on a stranger (negative v positive, 47% v 70%). CONCLUSIONS: These findings suggest that although most high-school students are willing and motivated to learn CPR, a smaller percentage of students had a negative attitude towards CPR that would act as a barrier to future learning or performance of resuscitation. Introducing CPR training to high schools is still recommended; however, this study shows the need to associate this training with positive references in an attempt to assist those for whom negative attitude may present as a barrier to learning and retaining CPR knowledge.

Adolescent↗
PubMed2005

The distribution of progenitor cells in the subependymal layer of the lateral ventricle in the normal and Huntington's disease human brain.

The recent demonstration of endogenous stem/progenitor cells in the adult mammalian brain raises the exciting possibility that these undifferentiated cells may be able to generate new neurons for cell replacement in neurodegenerative diseases such as Huntington's disease (HD). Previous studies have shown that neural stem cells in the rodent brain subependymal layer (SEL), adjacent to the caudate nucleus, proliferate and differentiate into neurons and glial cells and that neurogenesis occurs in the hippocampus and the SEL of the caudate nucleus in the adult human brain, but no previous study has shown the extent to which progenitor cells are found in the SEL in the normal and diseased human brain with respect to location. From detailed serial section studies we have shown that overall, there is a 2.7-fold increase in the number of proliferating cell nuclear antigen positive cells in HD (grade 2/3); most notably, the ventral and central regions of the SEL adjacent to the caudate nucleus contained the highest number of proliferating cells and in all areas and regions examined there were more cells in the HD SEL compared with the normal brain. Furthermore, progenitor cells colocalized with betaIII tubulin in a subset of cells in the SEL indicating neurogenesis in the HD brain. There was a 2.6-fold increase in the number of new neurons that were produced in the Huntington's disease SEL compared with the normal SEL; however, the Huntington's disease SEL had many more proliferating progenitor cells; thus, the proportion of new neuron production relative to the number of progenitor cells was approximately the same. This study provides new evidence of the pattern of neurogenesis in the normal and HD brain.

Aged↗
PubMed2002

Magnetization-orientation dependence of the superconducting transition temperature in the ferromagnet-superconductor-ferromagnet system: CuNi/Nb/CuNi.

The superconducting critical temperature (T(c)) of ferromagnet-superconductor-ferromagnet systems has been predicted to exhibit a dependence on the magnetization orientation of the ferromagnetic layers such that T(AP)(c)>T(P)(c) for parallel (P) and antiparallel (AP) configurations of the two ferromagnetic layers. We have grown CuNi/Nb/CuNi films via magnetron sputtering and confirmed the theoretical prediction by measuring the resistance of the system as a function of temperature and magnetic field. We find an approximately 25% resistance drop occurs near T(c) in Cu0.47Ni0.53(5 nm)/Nb(18)/CuNi(5) when the two CuNi layers change their magnetization directions from parallel to antiparallel, whereas there is no corresponding resistance change in the normal state.

Journal Article↗
PubMed2002

A systematic review of the use of atypical antipsychotics in autism.

Conventional antipsychotic medication is commonly prescribed to patients with autistic spectrum disorder. However, a high incidence of severe adverse reactions highlights the need to find more favourable treatments. Atypical antipsychotics may combine efficacy in ameliorating some autistic symptoms with a lower incidence of some adverse reactions. This article reviews the use of atypical antipsychotics in autistic disorder, with particular focus on behaviour, cognition and physical well-being. Thirteen studies using risperidone, three using olanzapine, one using clozapine, one using amisulpride and one using quetiapine were identified. Few firm conclusions can be drawn due to the limitations of the studies; however, there is an indication that risperidone may be effective in reducing hyperactivity, aggression and repetitive behaviours, often without inducing severe adverse reactions. Olanzapine and clozapine may also be effective; however, there is little evidence for using amisulpride or quetiapine in this population. Randomized trials are required to clarify the effectiveness of these agents.

Antipsychotic Agents↗
PubMed2001

Early-onset amyloid deposition and cognitive deficits in transgenic mice expressing a double mutant form of amyloid precursor protein 695.

We have created early-onset transgenic (Tg) models by exploiting the synergistic effects of familial Alzheimer's disease mutations on amyloid beta-peptide (Abeta) biogenesis. TgCRND8 mice encode a double mutant form of amyloid precursor protein 695 (KM670/671NL+V717F) under the control of the PrP gene promoter. Thioflavine S-positive Abeta amyloid deposits are present at 3 months, with dense-cored plaques and neuritic pathology evident from 5 months of age. TgCRND8 mice exhibit 3,200-4,600 pmol of Abeta42 per g brain at age 6 months, with an excess of Abeta42 over Abeta40. High level production of the pathogenic Abeta42 form of Abeta peptide was associated with an early impairment in TgCRND8 mice in acquisition and learning reversal in the reference memory version of the Morris water maze, present by 3 months of age. Notably, learning impairment in young mice was offset by immunization against Abeta42 (Janus, C., Pearson, J., McLaurin, J., Mathews, P. M., Jiang, Y., Schmidt, S. D., Chishti, M. A., Horne, P., Heslin, D., French, J., Mount, H. T. J., Nixon, R. A., Mercken, M., Bergeron, C., Fraser, P. E., St. George-Hyslop, P., and Westaway, D. (2000) Nature 408, 979-982). Amyloid deposition in TgCRND8 mice was enhanced by the expression of presenilin 1 transgenes including familial Alzheimer's disease mutations; for mice also expressing a M146L+L286V presenilin 1 transgene, amyloid deposits were apparent by 1 month of age. The Tg mice described here suggest a potential to investigate aspects of Alzheimer's disease pathogenesis, prophylaxis, and therapy within short time frames.

Aging↗
PubMed2001

Evaluation of 'Sun-safe': a health education resource for primary schools.

The aim of the study was to assess the effectiveness of 'Sun-safe', a computer-based resource designed to promote skin cancer awareness and educate children, aged 10-11 years, about the effects of excessive exposure to the sun and associated skin cancer preventive behaviours. Effectiveness was measured by changes in knowledge, attitudes and behavioural intentions using a self-completed questionnaire. A cluster, controlled evaluation design was used. Twelve schools were randomly allocated to the intervention arms of the study (workbook or computer), with a further four schools acting as controls (no intervention). One school allocated to the computer group had serious technical problems with their computers on the day of the intervention and had to be excluded from the study, leaving six schools in the workbook group and five in the computer group. One class in each of the 15 schools participated. The questionnaire was administered before the intervention, the day after and 6 weeks thereafter. The primary outcome measures were changes in mean scores at 6 weeks. In all, 376 children, 83% of the roll, completed both pre- and 6-week tests. Mixed-model analysis, allowing for pre-intervention score and the cluster effect, showed significant increases in knowledge scores in all three groups [workbook 2.36, 95% confidence interval (CI): 1.66 to 3.05; computer 1.73, 95% CI: 1.00 to 2.46; control 0.93, 95% CI: 0.11 to 1.74], but only the workbook group was significantly better than the control group (1.43, 95% CI: 0.36 to 2.50) and there was no significant difference between the intervention groups (0.63, 95% CI: -0.38 to 1.63). With regard to attitudes, both interventions showed significantly greater increases in scores than the control group, but there was no significant difference between them (workbook 2.37, 95% CI: 1.27 to 3.47; computer 1.92, 95% CI: 0.76 to 3.09; control -0.01, 95% CI: -1.28 to 1.27). Although the mean increases for behavioural intentions scores were small (workbook 0.66, 95% CI: 0.26 to 1.05; computer 1.11, 95% CI: 0.70 to 1.51; control 0.08, 95% CI: -0.37 to 0.52), those for the intervention groups were significantly better than the control group, but were not significantly different from each other. The evaluation showed significant improvements in knowledge, attitudes and behavioural intentions, which were still present 6 weeks after the intervention. This suggests that interventions employing the Sun-safe workbook and computer-based resources could be most usefully put into effect in the week before the start of the summer holidays.

Awareness↗
PubMed2001

Emergency transfer from independent hospitals to NHS hospitals: risk, reasons and cost.

BACKGROUND: In view of public concern about standards of emergency care in independent hospitals and the impact of transferred patients on NHS facilities we aimed to estimate the number and risk of emergency transfers from independent hospitals to NHS hospitals; to describe the circumstances; and estimate costs to the NHS. METHODS: Patients transferred in three months from 137 independent hospitals were identified from central records systems and local hospital enquiries. Circumstances were described by Directors of Nursing in telephone interviews. Numbers were weighted for whole year activity and non-participating hospitals to estimate total transfers in 1999. Medical Directors of NHS Trusts receiving the patients supplied durations of stay in critical care and other facilities. NHS Reference Costs were applied. RESULTS: There were 158 emergency transfers (plus 105 planned transfers, and 18 as a result of funding problems). Proportionately more emergency transfers were from hospitals lacking intensive care facilities. Patients over 65 years old constituted 61 per cent of transfers but only 25 per cent of all cases. Transfer followed major abdominal surgery in 42 (26 per cent) cases and major orthopaedic surgery in 31 (20 per cent), although these treatments constituted only 2 per cent and 3 per cent of the caseloads. There were an estimated 749 emergency transfers in 1999 (95 per cent confidence interval 640-875), a risk of 1 in 956 (all ages) and 1 in 392 (aged over 65); 729 had been funded privately, of whom two-thirds became NHS patients after transfer, costing Pound Sterling 2.61 million. CONCLUSIONS: The scale of emergency transfer (two per day) and resulting cost to the NHS is small. The risk is reducible if patients and interventions are matched to hospitals' critical care capabilities. Common clinical service guidelines should apply to NHS and independent hospitals.

Adolescent↗
PubMed2001

Analysis of Escherichia coli strains causing bacteriuria during pregnancy: selection for strains that do not express type 1 fimbriae.

Escherichia coli isolates from patients with bacteriuria of pregnancy were compared by PCR with isolates from patients with community-acquired cystitis for the presence of established virulence determinants. The strains from patients with bacteriuria of pregnancy were less likely to carry genes for P-family, S-family, and F1C adhesins, cytotoxic necrotizing factor 1, and aerobactin, but virtually all of the strains carried the genes for type 1 fimbriae. Standard mannose-sensitive agglutination of yeast cells showed that only 15 of 42 bacteriuria strains (36%) expressed type 1 fimbriae compared with 32 of 42 strains from community-acquired symptomatic infections (76%) (P < 0.01). This difference was confirmed by analysis of all isolates for an allele of the type 1 fimbrial regulatory region (fim switch), which negates type 1 fimbrial expression by preventing the fim switch from being inverted to the on phase. This allele, fimS49, was found in 8 of 47 bacteriuria strains from pregnant women (17.0%) compared with 2 of 60 strains isolated from patients with cystitis (3.3%) (P < 0.05). Determination of the phase switch orientation in vivo by analysis of freshly collected infected urine from patients with bacteriuria showed that the fim switch was detectable in the off orientation in 17 of 23 urine samples analyzed (74%). These data indicate that type 1 fimbriae are not necessary to maintain the majority of E. coli bacteriurias in pregnant women since there appears to be selection against their expression in this particular group. This is in contrast to the considered role of this adhesin in community-acquired symptomatic infections. The lack of type 1 fimbria expression is likely to contribute to the asymptomatic nature of bacteriuria in pregnant women, although approximately one-third of the bacteriuria isolates do possess key virulence determinants. If left untreated, this subset of isolates pose the greatest threat to the health of the mother and unborn child.

Alleles↗
PubMed2001

Attenuation of interleukin 8-induced nasal inflammation by an inhibitor peptide.

Polymorphonuclear neutrophils (PMNs) infiltrate tissue in response to chemoattractants, including interleukin 8 (IL-8). Infiltrating PMNs clear microorganisms but also cause tissue damage. We previously reported the presence in human bronchial lavage of a peptide that inhibits PMN functions. The current project assessed (1) effects of a synthetic analog of this peptide (synthetic neutrophil inhibitor peptide, SNIP) on IL-8-induced nasal inflammation in humans, (2) effects of SNIP on PMN apoptosis and chemotaxis, (3) specific binding of SNIP to PMNs, and (4) evidence of larger molecules with the SNIP sequence. Results show that SNIP attenuates IL-8-induced nasal inflammation, inhibits in vitro PMN chemotaxis to IL-8, and accentuates PMNs apoptosis. PMNs contain specific SNIP-binding sites and the integrin CR3 (CD11b/CD18), or a CR3-associated molecule, is one SNIP-binding molecule. Chemotaxis to IL-8 is most potently inhibited by SNIP in the presence of fibrinogen, a CR3 ligand. Antiserum against the SNIP sequence recognizes a 70-kDa protein in bronchoalveolar lavage and an anti-SNIP immunoaffinity column binds a 70-kDa protein in U937 cell culture supernatant. U937 cell mRNA contains a 1.8-kb transcript detected with degenerate oligonucleotides designed from the SNIP sequence. These studies demonstrate that a synthetic inhibitor peptide can attenuate in vivo nasal inflammation through downregulatory effects on PMNs.

Analysis of Variance↗
PubMed2001

Longitudinal effects of aging on serum total and free testosterone levels in healthy men. Baltimore Longitudinal Study of Aging.

Many studies have shown cross-sectional (and two small studies, longitudinal) declines in total and/or free testosterone (T) levels, with age, in men. The extent to which decline in T is the result of the aging process per se, as opposed to chronic illness, medication use, and other age-related factors, remains controversial. The frequency with which aging leads to T levels consistent with hypogonadism has also not been defined. These issues bear on the potential use of T replacement in aging men, because aging and hypogonadism have, in common, reduced bone and lean body mass and muscle strength and increased total and abdominal fat. We measured T and sex hormone-binding globulin (SHBG), by RIA, in stored samples from 890 men in the Baltimore Longitudinal Study on Aging. Using a mixed-effects model, we found independent effects of age and date of sampling to reduce T levels. After compensating for date effects, which investigation suggested was artifactual, we observed significant, independent, age-invariant, longitudinal effects of age on both T and free T index (free T index = T/SHBG), with an average change of -0.124 nmol/L.yr and -0.0049 nmol T/nmol SHBG.yr. T, but not free T index, also decreased with increasing body mass index. Use of beta-blocking drugs was associated with higher T and higher free T index levels. Using total T criteria, incidence of hypogonadal T levels increased to about 20% of men over 60, 30% over 70 and 50% over 80 yr of age, and even greater percentages when free T index criteria were employed. Our observations of health factor independent, age-related longitudinal decreases in T and free T, resulting in a high frequency of hypogonadal values, suggest that further investigation of T replacement in aged men, perhaps targeted to those with the lowest serum T concentrations, are justified.

Adult↗
PubMed2001

Evaluation of a program to promote positive parenting in the neonatal intensive care unit.

PURPOSE: To describe and evaluate a parent education program to promote positive parenting in the NICU. DESIGN: Program evaluations completed by parent participants and staff members. SAMPLE: 104 parents (59 mothers and 45 fathers) who attended the Parent's Circle; also 44 NICU or SCN staff members. MAIN OUTEOME VARIABLE: Family and staff evaluations of the Parent's Circle program. RESULTS: Families reported that attending Parent's Circle helped them gain perspective on their situation, feel supported, learn key developmental concepts, locate hospital and community resources, and optimize interactions with their fragile infant. Staff reported that the knowledge parents gained from Parent's Circle influenced their interactions and behaviors in the NICU.

Adaptation, Psychological↗
PubMed2001

Cervical teratoma in a dog.

A young adult boxer dog was examined for a painless swelling in the left cranial cervical area that was refractory to antibiotic therapy. Ultrasound examination revealed a hypoechoic mass abutting the rostrolateral aspect of the left mandibular salivary gland. The cystic mass was excised and was found to extend through the capsule of the salivary gland and appeared to be confluent with the glandular tissue at this point. Histopathological examination of the excised tissue demonstrated tissue from all 3 germinal layers. There was no indication of malignancy and the mass was diagnosed as a benign cervical teratoma. Hypotheses regarding the origin of teratomas in general are discussed and the origin of the teratoma in this case is suggested.

Animals↗