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P Ley

Publications and source records attributed to P Ley.

At least 19 recordsLinked to original sources
PubMed1995

Comparison of the coexpression of CD38, CD33 and HLA-DR antigens on CD34+ purified cells from human cord blood and bone marrow.

Human umbilical cord blood (UCB) cells are currently considered as a potential source of stem cells for transplantation. However, it remains unclear whether a single collection of UCB contains enough progenitors to allow a successful engraftment in adult patients. We were interested in the comparison of the frequency of primitive progenitors in UCB and in human bone marrow (BM). UCB and BM CD34+ cells were purified and compared for their coexpression of CD38, CD33 and HLA-DR. UCB and BM mononuclear fractions were enriched in CD34+ cells using the CEPRATE LC system (CellPro, Bothell, WA). Double-labeling analysis with a flow cytometer showed that 67.9 +/- 7.2% of UCB CD34+ cells are CD38-, while in BM only 10.9 +/- 4.9% of CD34+ are CD38- (p < 0.001). Moreover, our study indicated that a significantly higher percentage of UCB CD34+ is CD33- (97.1 +/- 1.2%) compared to BM (61.8 +/- 8.6%) (p = 0.013). The coexpression of CD34 with HLA-DR was not significantly different in UCB and in BM (respectively, 86.3 +/- 2.7% and 92.7 +/- 5.1%). On the other hand, in vitro assays showed that the number of multipotent (colony-forming units granulocyte-erythroid-macrophage-megakaryocyte [CFU-GEMM]), myeloid (colony-forming units granulocyte-macrophage [CFU-GM]) and erythroid (burst-forming units-erythroid [BFU-E]) progenitors is lower in the CD34+ population from UCB than from BM. In conclusion, in UCB, we have found a significantly higher percentage of CD34+ cells which lacked the expression of CD38 and CD33 antigens suggesting that UCB contains higher proportions of immature progenitor cells (CD34+CD38- and CD34+CD33-) than BM. It seems thus likely that fewer UCB CD34+ cells than BM CD34+ cells would be required for sustained engraftment following transplantation.

Antigens, CD↗
PubMed1994

Modulation of human cord blood progenitor cell growth by recombinant human interleukin 3 (IL-3), IL-6, granulocyte-macrophage colony stimulating factor (GM-CSF) and stem cell factor (SCF) in serum-supplemented and serum-free medium.

UNLABELLED: We evaluated the growth of cord blood myeloid progenitors or colony forming units granulocyte-macrophage (CFU-GM) and their response to various recombinant growth factors or colony stimulating factors (CSFs): interleukin 3 (IL-3), IL-6, granulocyte-macrophage CSF (GM-CSF) and stem cell factor (SCF). Using classical stimulant (human placenta conditioned medium or HPCM), we observed a significantly higher day-14/day-7 CFU-GM ratio in CB than in bone marrow (BM). The association of IL-3, IL-6, GM-CSF and SCF induced significantly more CB day-14 CFU-GM than HPCM. This effect is significantly greater in CB than in bone marrow. Since fetal calf serum (FCS) is known to contain inhibitors, we have compared the ability of CSFs to induce CFU-GM formation in FCS-supplemented and FCS-free culture. In CB, using HPCM, we obtained significantly more CFU-GM in FCS-free medium than in FCS-supplemented medium. This difference was corrected by the addition of anti-transforming growth factor-beta (TGF-beta) neutralizing antibody. However, with the association of the four CSFs, no significant difference between FCS and FCS-free culture was observed. IN CONCLUSION: a) day-14/day-7 CFU-GM ratio was higher in CB than in BM indicating that CB CFU-GM are more primitive than BM CFU-GM; b) FCS can be successfully replaced by serum-free medium; c) FCS contains inhibitors of day-14 CFU-GM and among them TGF-beta; and d) the association IL-3, SCF, GM-CSF and IL-6 seems able to totally overcome the inhibitory effect of FCS.

Bone Marrow↗
PubMed1994

Better medication compliance is associated with improved control of childhood asthma.

Our previous studies have shown that medication compliance in children prescribed continuous treatment for asthma is poor, and that an intervention can improve the level of compliance. The present study examined the effects of an intervention on the clinical course of moderately severe asthma. At each of six clinic visits, spirometry was performed, medication compliance was assessed by questionnaire, and the physicians made an overall assessment of asthma severity (Severity Score) and provided a score for asthma control (Control of Asthma Score). Peak expiratory flow rates were measured twice daily for one month prior to each clinic visit, and the coefficient of variation (% CV) was calculated. Subjects received the intervention after at least two visits, and 53 of the 78 recruits completed the study. Following the intervention, % CV, Control of Asthma Score, Severity Score and % compliance improved, showing that better medication compliance was associated with better control of moderately severe asthma.

Adolescent↗
PubMed1993

Modulation of the growth of hematopoietic human stem cells by growth factors: comparison of umbilical cord blood with bone marrow.

The growth of cord blood and bone marrow myeloid mononuclear cells in response to single and multiple growth factors has been examined. Single factors such as IL-3, IL-6, GM-CSF, and stem cell factor did not optimally stimulate growth of cord blood CFU-GM. However a synergistic stimulation was observed when the factors were combined. This effect was seen in both the presence and absence of added fetal calf serum.

Antigens, CD↗
PubMed1987

Health beliefs, satisfaction and compliance.

Relationships were studied between measures of parents' Health Beliefs, satisfaction, and compliance in 174 children suffering from asthma. It was found that while concurrent measures of Health Belief Model (HBM) variables and compliance were significantly correlated, measures of HBM variables did not predict future compliance. Satisfaction measures, however, not only correlated with concurrent measures of compliance but also predicted future compliance. It is concluded that these findings are consistent with the view that in this sample health beliefs were reactive to compliance behaviours and that they did not have a casual effect on compliance.

Adolescent↗
PubMed1986

Effects of intervention on medication compliance in children with asthma.

We have assessed the effects of intervention on medication compliance in asthmatic children. The intervention comprised both written information about the medications and behavioural strategies effected by the physician. Children were assigned at random to either control (received no intervention) or test (received the intervention) groups. Compliance was assessed by questionnaire. The mean compliance for the test (78.0%; n = 93) and for the control (54.5%; n = 103) groups differed significantly (P less than 0.001; Mann-Whitney U-test). The test group had a better knowledge of asthma and of the medications, and was more satisfied with the physician and with the regimen than was the control group. These variables were also related to good compliance. This study demonstrates that a programme of intervention can significantly improve medication compliance and can be accompanied by increases in the knowledge of, and satisfaction with, treatment.

Asthma↗
PubMed1985

Doctor-patient communication: some quantitative estimates of the role of cognitive factors in non-compliance.

Patients frequently fail to understand what they are told. Further, they frequently forget the information given to them. These factors have effects on patients' satisfaction with the consultation. All three of these factors--understanding, memory and satisfaction--have effects on the probability that a patient will comply with advice. The levels of failure to understand and remember and levels of dissatisfaction are described. Quantitative estimates of the effects of these factors on non-compliance are presented.

Attitude to Health↗
PubMed1984

The incidence of acute brain injury and serious impairment in a defined population.

Studies on the incidence and epidemiologic features of brain injury and the immediate medical outcomes are few, and published results have serious methodological inconsistencies which prohibit comparisons. This study provides incidence rates of brain injury among the residents of San Diego, California. Cases had clinical confirmation and onset of injury occurred during 1981. The 3358 cases identified represent a rate of 180/100,000 with males having a 2.2 times higher rate than females. Rates were highest for males aged 15-24 years and, for both genders, those over age 70. Forty-eight per cent of all cases were from transport-related causes, followed by falls (21%) and assaults (12%). Over 11% were dead-on-arrival, and 16% were classified as having moderate or severe brain damage on admission to a hospital. Age- and sex-specific incidence rates varied according to external cause of injury. For example, for most subcategories of motor vehicle crashes and for assaults, the incidence rate was highest among males aged 15-24, while for brain injuries from falls or firearms, highest incidence rates were observed in older age groups. Almost 7% of all cases discharged alive from an acute care hospital had significant neurologic sequelae. The impact of brain injury is discussed as a major unresolved public health problem.

Accidents, Traffic↗
PubMed1982

Satisfaction, compliance and communication.

The literature on communication, compliance, and patient satisfaction is selectively reviewed. As in earlier reviews, it is concluded that dissatisfaction with communication remains widespread, as does lack of compliance with medical advice. Related factors include poor transmission of information from patient to doctor, low understandability of communications addressed to the patient, and low levels of recall of information by patients. There does not appear to be any evidence that provision of additional information leads to adverse reactions by patients. Theoretical approaches to communication and compliance are described, and it is concluded that these should be used to direct future research.

Communication↗
PubMed1979

Memory for medical information.

The frequency with which patients fail to recall advice presented by their doctors is discribed. The amount forgotten is shown to be a linear function of the amount presented, to be correlated with the patient's medical knowledge, anxiety level and possibly age, but not with intelligence. It is probable that instructions and advice are more often forgotten than other information, and that this is the result of their low perceived importance, and their being presented late in the series of statements presented-there being (a) a primacy effect in recall of medical information, and (b) a tendency for statements perceived as more important to be better recalled. Experiments to control the content and amount of forgetting are described. Control of content can be obtained by use of the primacy and importance effects, while control of amount forgotten can be achieved by use of (a) simpler language, (b) explicit categorization, (c) repetition, and (d) concrete-specific rather than general-abstract advice statements.

Adult↗
PubMed1976

A method for decreasing patients' medication errors.

Eighty anxious and eighty depressed patients were assigned randomly to receiving one of three versions of an information leaflet about their medication, or to receiving no leaflet at all. Mean medication errors were reduced from 15 to 4% by provision of suitably constructed leaflets. The results show the practical importance of informing patients about their medication and of paying attention to the difficulty level of any leaflets issued.

Antidepressive Agents↗
PubMed1976

Increasing patients' satisfaction with communications.

This paper reports a successful experimental attempt to increase satisfaction with communications amongst general medical patients. A group of patients who received extra interviews designed to increase their understanding of what they had been told about their illnesses showed significantly greater satisfaction than patients treated in the usual manner, and patients who received extra placebo interviews about their hospital stay. Changes in satisfaction with communications over the period following discharge from hospital are also described and possible reasons for them are discussed.

Adult↗