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L C Jones

Publications and source records attributed to L C Jones.

At least 55 records · Page 3Linked to original sources
PubMed1996

Healing fictions': stories of choosing in the aftermath of the detection of fetal anomalies.

Between the cultural story of prenatal diagnosis emphasizing the expansion of choice and the countercultural story emphasizing the lack of choice are the individual stories of choosing told by expectant and new parents after learning of the existence of a fetal impairment. The results of a qualitative, descriptive study involving 40 interviews with 15 women and 12 of their partners suggest that they had often 'backed into', as opposed to having actively chosen or refused, prenatal testing. After learning of their babies' impairments, they constructed subtly different accounts of pregnancies continued or terminated that located the moral agency for effecting these pregnancy outcomes either in themselves or elsewhere. These emplotments of choice can be summarized as nature's choice, disowned choice, choice lost, close choice and choice found. The findings raise questions concerning which of these or other constructions of choice in the aftermath of positive fetal diagnosis are the most effective in promoting psychological recovery and optimum parent-infant interactions.

Abortion, Induced↗
PubMed1996

Couples' evaluations of foreknowledge of fetal impairment.

The Western cultural presumption that knowledge is a right and a good is integral to current discussions of prenatal diagnosis. Little is known, however, about how couples obtaining positive fetal diagnoses evaluate this knowledge for their own lives and whether, or how, they are advantaged in relation to couples learning about their baby's impairment after birth. Findings from 40 interviews with expectant parents obtaining positive prenatal diagnoses suggest that couples both value and question the value of fetal foreknowledge and that this knowledge temporally relocates, rather than substantively alters, parental responses and infant outcomes.

Adaptation, Psychological↗
PubMed1996

Cell-specific expression of the rat secretogranin II promoter.

Secretogranin II (SgII) is a member of the granin family of secretory proteins, which are selectively expressed in neuroendocrine cells. As a first step in understanding the molecular basis for cell type-specific expression of SgII, we isolated a 12-kb clone from a rat genomic library that contained the entire rat SgII coding region, the transcription initiation site, and approximately 3 kb of 5'-flanking region. Within 75 bp of the transcription start site (+1) we located a TATA box and a consensus cAMP responsive element. Within the 5'-flanking region, a number of potential cis-acting elements were identified, including 2 Pit-1 binding sites, 15 E box motifs, and near-perfect matches for AP-1 and AP-2 sites. To demonstrate cell type-specific expression the rat SgII gene, a plasmid containing 2.6 kb of the 5'-flanking region of the SgII gene fused to the luciferase reporter gene (p2774Luc) was transfected into rat pheochromocytoma PC-12 cells, rat pituitary GH4C1 (GH) cells, human BE(2)-M17 (M17) neuroblastoma cells, and mouse fibroblast NIH/3T3 cells. The promoter activity was 6- to 36-fold higher in neuroendocrine cells than in NIH/ 3T3 cells. Progressive deletions in the 5'-flanking region to 61 bp upstream of the start site (p223Luc) had no effect on promoter activity in PC-12 cells. On the other hand, a 5'-deletion in the SgII promoter to -1032 increased promoter activity 3.8-fold in GH cells. This level of expression was maintained when the SgII promoter was further truncated to -189, whereas truncation to -61 resulted in a 2.6-fold reduction in promoter activity. These results suggest that the sequence between -61 and +162 bp is sufficient for SgII promoter activity in PC-12 cells. However, other elements in the 5'-flanking region contribute to both positive and negative regulation of the rat SgII gene in GH cells.

Animals↗
PubMed1995

Regulation of secretogranin II mRNA in rat neuronal cultures.

The regulation of SgII mRNA expression was investigated in primary cultures of neurons prepared from the hypothalamus and brainstem of 1-day-old rats. The administration of forskolin (FSK) resulted in a time- and dose-dependent increase in SgII mRNA expression, a 9-fold effect within 6 h being achieved with 10 microM FSK, which maximally increased cellular cAMP levels. SgII mRNA levels remained elevated for 24 h. Activation of protein kinase C with 100 nM phorbol 12-myristate 13-acetate (PMA) also increased SgII mRNA expression, although induction with PMA was slower and more moderate (3.8-fold above control after 24 h). Neither 10 microM 1,9-dideoxyforskolin nor 100 nM 4 alpha-phorbol 12,13-didecanoate, inactive analogues of FSK and PMA respectively, had an effect on SgII mRNA. Depolarization of neuronal cultures with 50 mM KCl had a small and variable effect on SgII mRNA levels (1.8-fold above control) in neuronal cultures and did not influence induction with FSK. To investigate whether neuron-like regulation of SgII mRNA expression could be reproduced in PC12 cells, PC12 cells were treated with 100 nM nerve growth factor (NGF) for 7 days prior to challenge with FSK or PMA. Whereas NGF alone modestly increased SgII mRNA expression in PC12 cells (1.8-fold above control), it did not uncover a stimulatory effect of FSK or PMA. These studies indicate that SgII mRNA expression is enhanced by an increase in cellular cAMP and activation of protein kinase C in primary cultures of neurons and emphasize that SgII mRNA is regulated in a cell-specific manner.

Animals↗
PubMed1995

Comparison of three psychophysical techniques for estimating body-size perception.

Perception of body size was recorded for 63 university students (M age = 25.3 yr., 41 women) who estimated their own body size using three methods. Using the method of adjustment, subjects over- or underestimated their body size. A signal-detection analysis indicated that subjects were sensitive to detecting a 4% distortion in body size and that there was no systematic bias for reporting distortion as present or absent. Scores on the adaptive probit estimation task were significantly correlated with values for point of subjective equality and the size judgements with the method of adjustment. Over-all, this experiment demonstrated adaptive probit estimation as a reliable indicator of perceived body size, sensitivity in detecting size distortion, and response bias in making body-size judgements.

Adolescent↗
PubMed1995

History of the contralateral knee after primary knee arthroplasty for osteoarthritis.

Published reports of series of total knee replacements vary between 20% and 75% in the percentage of patients eventually having bilateral replacements. There are no data in the literature on the predicted course of the contralateral knee for patients presenting for total knee replacement. This study reviewed the history of the contralateral knee in patients with a diagnosis of osteoarthritis presenting for unilateral primary total knee arthroplasty. The current study group comprised 185 patients who had either a minimum 5 year followup (range 5-12.5 years) or who were known to have had a second knee arthroplasty before 5 years. Evaluation included a full clinical and radiographic examination of the contralateral knee at index arthroplasty and at final followup. Of the 185 patients, the contralateral side initially was asymptomatic in 36%, mildly symptomatic in 16%, moderately symptomatic in 28%, and severely symptomatic in 20%. Seventy-nine (43%) knees eventually underwent contralateral arthroplasty. Ninety-three percent of patients who had moderate or severe symptoms and severe radiographic arthritis of the contralateral side at the time of presentation later underwent total knee replacement. However, patients who presented initially with mild symptoms or who had no symptoms had only a 9% incidence of knee arthroplasty.

Adult↗
PubMed1995

Psychosocial benefits of postmastectomy lymphedema therapy.

The effect of a comprehensive lymphedema management program was assessed in 25 patients in whom moderate to severe lymphedema had developed after surgery and/or radiotherapy for carcinoma of the breast. Intensive treatment (4 weeks) involved massage, compression bandaging, and sequential pneumatic compression, with an adjunct program of education to provide skills in exercise, massage, bandage, and containment garment use. The intensive treatment phase was followed by a self-management phase based on the skills that had been acquired. A significant reduction in limb circumference and volume, with continuing improvement over 12 months of self-management, was observed. There was a decrease in need for physical assistance. Quality of life generally remained high and stable throughout the 12 months. Quality of life specific to lymphedema, however, declined during the intensive phase of treatment, but recovered and surpassed pretreatment levels during the self-management phase of treatment. Perceived comfort and strength in the lymphedematous limb improved, and perceived size decreased. The study confirmed that the combination of multimodal physical therapy and education for self-management reduces lymphedema and its adverse subjective consequences and maintains the improvement thus achieved.

Adult↗
PubMed1994

Post-mastectomy lymphoedema treatment and measurement.

OBJECTIVE: To evaluate multimodal treatment (massage, pneumatic compression, bandaging and education) of post-mastectomy lymphoedema and to review methods of measurement of lymphoedema. DESIGN: Prospective cohort study with 12 months' follow-up. PATIENTS: Twenty-five consecutive women referred for lymphoedema examination after mastectomy to a private day-patient clinic attached to a tertiary referral hospital. INTERVENTION: Patients received multimodal therapy, including education on self-management techniques, for four weeks. MAIN OUTCOME MEASURES: Changes in body weight, limb circumference and volume, and patient reports of self-management (exercise, massage, bandaging and sleeve wearing). RESULTS: Excess limb volume decreased by approximately 40% immediately after treatment and by over 50% at 6 months' follow-up, remaining stable to 12 months' follow-up. Self-management that required assistance (massage and bandage wearing) declined more after treatment than did exercise or compression sleeve wearing. Correlations between body mass and limb volume and self-management and limb volume reduction were non-significant. CONCLUSION: Multimodal therapy reduced lymphoedematous limb volume by at least half in 18 of 25 patients. Patients can maintain these reductions independently through exercise and sleeve wearing and without further treatment. We used a replicable method of measuring lymphoedema, which we recommend for adoption by researchers in this field.

Arm↗
PubMed1994

A right to die?

Often nurses within the critical care setting face moral dilemmas when confronted with issues surrounding resuscitation and withdrawal of treatment. In this article the nurses' role and the patients' rights regarding resuscitative measures and withdrawal of basic and advanced forms of life support are discussed. Cases that have improved decision-making have been used to illustrate the dilemmas involved. It is hoped that critical care nurses will become more aware of their vital role when these decisions are being made.

Advance Directives↗
PubMed1993

Polymethylmethacrylate particles enhance DNA and protein synthesis of human fibroblasts in vitro.

Aseptic loosening of polymethylmethacrylate (PMMA) fixed prosthesis is characterized by formation of a radiolucent fibrous membrane, accumulation of inflammatory cells and osteolysis. Since this membrane is produced by fibroblasts, it is likely that these connective tissue cells play a critical role in the loosening process. Whether fibroblasts form the radiolucent membrane in response to stimulation by PMMA has not yet been established, nor is it known whether fibroblasts play a role in attracting inflammatory cells to the bone-cement interface by secreting chemical mediators. To address this question, we analyzed the in vitro response of normal human fibroblasts to PMMA. Cells were plated with 10(5)/mL Dulbecco minimal essential medium and were incubated 4 h later with PMMA particles, polystyrene (PS) particles, or medium alone. Proliferative capacity monitored by incorporation of 3H-thymidine was significantly increased following a 48 h exposure to PMMA. Protein synthesis determined by incorporation of 14C-leucine and 14C-proline was also increased. In contrast, levels of secreted prostaglandin (PG) E2 assayed immunoenzymatically was not altered by PMMA. Fibroblasts exposed to control PS did not change their proliferative or protein synthetic activity. Fibroblasts internalized PMMA and PS particles without detectable ultrastructural damage. PMMA enhancement of fibroblast proliferative capacity and protein synthetic ability observed in our in vitro assay system suggests similar effects on fibroblasts in vivo.

Cells, Cultured↗
PubMed1993

Total hip replacement without cement for non-inflammatory osteoarthrosis in patients who are less than forty-five years old.

Forty-two patients (forty-four hips) who, at an age of less than forty-five years, had a total hip replacement without cement for the treatment of non-inflammatory osteoarthrosis, were followed for three to seven years (average, four and one-half years). At the latest follow-up evaluation, thirty-seven hips (84 per cent) had an excellent Harris rating; three (7 per cent), good; one (2 per cent), fair; and three (7 per cent), poor. The mean Harris hip score was 92 points, compared with 43 points before the operation. Two hips (5 per cent) had a revision due to complications. In another hip, there was a progressive radiolucent line around the femoral component, increased shedding of beads, and a low score for fixation and stability, according to the criteria of Engh et al. We concluded that total hip arthroplasty without cement, at least for the time-period studied, has a high rate of success for the management of patients less than forty-five years old who have non-inflammatory osteoarthrosis of the hip.

Adult↗
PubMed1993

The rationale for cementless total hip replacement.

Current cementing techniques of distal plugging, pulsatile water cleaning of the canal, and retrograde filling with PMMA in a low-viscous state prepared using porosity reduction techniques and then pressurized have been shown to give excellent results at 10 or more years after operation. However, physical and aging characteristics of PMMA do not guarantee that those results will hold up in the 20- to 30-year time frame. Fifteen-year experience with bony ingrowth systems indicate the development of a durable interface without PMMA, although the interface does appear more vulnerable to attack by the biologic reaction to HMWPE debris. Bone remodeling appears more favorable around proximally fixed bone ingrowth prostheses than around distally fixed prostheses. Softening of the physical characteristics of the stem tip may reduce the incidence of thigh pain. Patients with high activity potential and a life expectancy of greater than 25 years should be strongly considered for a proximally fixed bone ingrowth or ongrowth prosthesis.

Adult↗
PubMed1992

Evaluation of marrow perfusion in the femoral head by dynamic magnetic resonance imaging. Effect of venous occlusion in a dog model.

RATIONALE AND OBJECTIVES: There is a continuing need for a greater sensitivity of magnetic resonance imaging (MRI) in the diagnosis of avascular necrosis (AVN). Previously, it was demonstrated that a dynamic MRI method, with gadolinium-DTPA (Gd-DTPA) enhancement, can detect acute changes not seen on spin-echo images after arterial occlusion in a dog model. Because venous congestion appears to be a more directly relevant hemodynamic abnormality in a majority of clinical AVN cases, the authors extended the dynamic MRI technique to study changes in venous occlusion. METHODS: Dynamic MRI of the proximal femur was performed in five adult dogs before and after unilateral ligation of common iliac and lateral circumflex veins. Sixteen sequential gradient-recalled pulse sequence (GRASS) images (time resolution = 45 mseconds, echo time = 9 mseconds, flip angle = 65 degrees) were obtained immediately after a bolus intravenous injection of 0.2 mmol/kg of Gd-DTPA. Simultaneous measurements of regional blood flow were made using the radioactive microsphere method. RESULTS: After venous ligation, there was a 25% to 45% decrease in the degree of enhancement compared with preligation values on the ligated side. The decrease in cumulative enhancement (integrated over the entire time course) was statistically significant. The occlusion technique was verified by confirming a statistically significant decrease in blood flow determined by the microsphere method. CONCLUSIONS: Dynamic Gd-DTPA-enhanced fast MRI technique can detect acute changes in bone marrow perfusion due to venous occlusion. This technique may have applications in the early detection of nontraumatic AVN.

Animals↗
PubMed1992

Multi-frequency bioelectrical impedance augments the diagnosis and management of lymphoedema in post-mastectomy patients.

The value of multiple frequency bioelectric impedence analysis (MFBIA) in the monitoring and management of post-mastectomy lymphoedema of the arm was evaluated in 15 patients and controls. The technique was found to produce quantitative agreement with a clinical diagnosis of lymphoedema and with the currently-used measure (limb volume calculated from circumferential measurements) of limb size. The significance of this finding lies in MFBIA being diagnostically informative: it indicates when an observed change in limb volume is directly, albeit theoretically, attributable to accumulation of extracellular fluid. MFBIA potentially offers the means for earlier definitive diagnosis and more-accurate monitoring of extracellular fluid changes during and after treatment.

Adult↗
PubMed1991

Families of children with developmental disabilities: an examination of family hardiness.

Using the Typology Model of Adjustment and Adaptation, a family stress model, relationships among family hardiness, family stressors, family appraisal, coping, social support, and satisfaction with family functioning were examined in a sample of 57 families of children with developmental disabilities. Family hardiness was associated with family appraisal, social support, parental coping related to maintaining family integration, and satisfaction with family functioning. Higher satisfaction with family functioning was correlated with coping-integration, network support, functional support, and hardiness. Lower satisfaction with family functioning was associated with higher family stressor scores, social support loss, and increased parental age. Over 42% of the variance in family functioning was accounted for by family hardiness, functional support, family stressors, and parental age. The results highlight the value of continued investigations of hardiness in families.

Adaptation, Psychological↗
PubMed1991

Bone marrow perfusion evaluated with gadolinium-enhanced dynamic fast MR imaging in a dog model.

The authors studied, in a dog model, the feasibility of using gadolinium-enhanced dynamic magnetic resonance (MR) imaging to noninvasively monitor bone marrow perfusion of the proximal femur. With a gradient-recalled acquisition, sequential images of 10 hips in five healthy dogs were obtained for 14 minutes after an intravenous bolus injection of 0.2 mmol of gadopentetate dimeglumine per kilogram. The study was repeated after unilateral arterial embolization of major femoral vessels. Radiolabeled microspheres were injected before and after vessel occlusion. After unilateral embolization, statistically significant differences in enhancement were observed between embolized and control sides (eg, 31% vs 83% average peak enhancement in the femoral neck). There was a high correlation (r = .81 [average]) between the MR data and the microsphere blood flow measurements. The postembolization data indicate that contrast-enhanced fast MR imaging may allow early detection of abnormal bone marrow flow. This technique may be valuable in evaluating patients at risk for avascular necrosis of the femoral head, especially in posttraumatic cases.

Animals↗