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M J Marshall

Publications and source records attributed to M J Marshall.

At least 19 recordsLinked to original sources
PubMed1996

Inhibition of prostaglandin synthesis leads to a change in adherence of mouse osteoclasts from bone to periosteum.

When mouse parietal bones were incubated for 1 day in medium containing indomethacin (Ind), the number of tartrate-resistant acid phosphatase-positive osteoclasts (TRAP+OC) counted on the bone surface was drastically reduced. This reduction did not occur with calcitonin or if the endocranial membrane (periosteum) was removed prior to incubation with Ind. The aim of this work was to determine the mechanism involved. TRAP+OC were found to be increased on the endocranial membrane adjacent to the resorbing surface after Ind treatment, compared with cultures supplemented with parathyroid hormone (PTH) or prostaglandin E2 (PGE2). However, this increase accounted for only half of those lost from the bone surface. TRAP negative osteoclasts were also seen on the membrane and, to a lesser extent, on the bone. Increased TRAP specific activity could be extracted from the endocranial membranes of bones incubated with Ind compared with PGE2 controls. When bones that had been exposed to Ind were then cultured for 1 day in PGE2, an increase in TRAP+OC occurred. This increase was blocked by the removal of the endocranial membrane prior to incubation with PGE2. We conclude that when prostaglandin production ceases, TRAP+OC become less adherent to bone and more adherent to the endocranial membrane. Stimulators of bone resorption appear to reverse this process.

Acid Phosphatase↗
PubMed1996

Osteoclasts are not the major source of interleukin-6 in mouse parietal bones.

Interleukin-6 (IL-6) is produced by bone cells and has been shown to stimulate the proliferation of osteoclast progenitors. Which cells in bone produce IL-6 is controversial. This article tests the hypothesis that tartrate-resistant acid phosphatase-positive osteoclasts (TRAP + OC) in neonatal mouse parietal bones are the major source of IL-6. Bones were preincubated with indomethacin to decrease the number of TRAP + OC and the amount of IL-6 produced. Incubation with parathyroid hormone or prostaglandin E2 increased the number of TRAP + OC and the amount of IL-6 produced. Calcitonin and 17 beta-estradiol inhibited this increase in TRAP + OC but had no effect on IL-6 production. 1,25-dihydroxy-vitamin D3 also stimulated an increase in TRAP + OC number but did not cause increased IL-6 production. Both the endocranial and ectocranial membranes of these bones produced large amounts of IL-6. TRAP activity in extracts of endocranial membranes was 14-fold that of the ectocranial membrane and, histochemically, some TRAP + cells could be detected here. However, the ectocranial membranes produced more IL-6 than the endocranial membranes. We conclude that TRAP + OC are not a major source of IL-6 in this system.

Acid Phosphatase↗
PubMed1995

The number of tartrate-resistant acid phosphatase-positive osteoclasts on neonatal mouse parietal bones is decreased when prostaglandin synthesis is inhibited and increased in response to prostaglandin E2, parathyroid hormone, and 1,25 dihydroxyvitamin D3.

The culture of parietal bones from 4-day old mice in indomethacin (Ind) for 1 day caused a large reduction in the number of tartrate-resistant acid phosphatase positive osteoclasts (TRAP + OC) relative to both control bones and to freshly isolated bones. This reduction did not occur if prostaglandin E2 (PGE2) was present. When 5-bromo-2'-deoxyuridine (BDU) was injected into 4-day old mice, newly formed TRAP + OC nuclei became labeled 1 day later; these bones were then cultured with Ind for 1 day. TRAP + OC and newly labeled TRAP+OC nuclei were commensurately decreased in number. This suggests an active down-regulation rather than merely the inhibition of new TRAP+OC formation. Incubation of bones with Ind and either PGE2, parathyroid hormone, or 1,25 dihydroxyvitamin D3 for 6 hours following a 1-day preincubation in Ind, resulted in an increase in TRAP + OC compared with Ind alone. Using BDU labeling in vitro and in vivo, we show that this increase in number of TRAP+OC is not the result of cell proliferation, but rather differentiation of postmitotic precursors.

Acid Phosphatase↗
PubMed1994

Interleukin-6 does not mediate the stimulation by prostaglandin E2, parathyroid hormone, or 1,25 dihydroxyvitamin D3 of osteoclast differentiation and bone resorption in neonatal mouse parietal bones.

The cytokine interleukin-6 (IL-6) was produced by neonatal mouse parietal bones during a 6- or 48-hour culture period in response to prostaglandin E2 (PGE2) and bovine parathyroid hormone (PTH) 1-34 fragment but not 1,25-dihydroxyvitamin D3 [1,25(OH)2D3]. At the same time there was an increase in tartrate-resistant, acid phosphatase-positive osteoclasts (TRAP+OC) with all three osteotropic effectors over 6 hours, and an increase in 45Ca release over 48 hours. TRAP+OC numbers on PGE2-stimulated bones were positively correlated with IL-6 concentration. Our aim was to determine if IL-6 mediated this response. Recombinant human IL-6 (rhIL-6) was added to parietal bones in culture at concentrations within the range that PGE2 or PTH would produce during incubation. However, over 6 or 48 hours, rhIL-6 did not stimulate TRAP+OC to increase in number nor did it cause an increase in calcium release over 48 hours. Adding an antibody against mouse IL-6 to bone cultures stimulated with PTH or PGE2 neutralized the resulting IL-6 bioactivity by up to 92% but did not inhibit TRAP+OC formation. We conclude that although IL-6 is produced in response to two important stimulators of bone resorption, it does not mediate osteoclast differentiation or bone resorption in this model.

Acid Phosphatase↗
PubMed1994

Prostaglandin E2 stimulates the production of interleukin-6 by neonatal mouse parietal bones.

The pleiotropic cytokine interleukin-6 (IL-6) is thought to be involved in bone homeostasis. A number of bone resorbing agents have been shown to induce the release of IL-6 from bone. We wished to determine whether prostaglandin E2 (PGE2), which is a mediator of bone resorption, can elicit the production of IL-6. IL-6 was measured by the proliferative response of B9 hybridoma cells and could be completely neutralised by an anti-IL-6 antibody. Parietal bones from neonatal mice were maintained in culture in the presence of indomethacin (10(-6) M) with or without PGE2. The time course and dose-response to PGE2 of IL-6 production were determined. After 6 h in culture, 10(-8) M PGE2 produced significantly more IL-6 than the controls (P < 0.005). PGE2 (10(-6) M) stimulated the production of a mean of 12.8 ng/ml IL-6 over 6 h. Preincubating bones with indomethacin for 20 h prior to a 6 h culture with indomethacin led to a lowering of the production of IL-6 (mean 1.8 ng/ml) compared to bones cultured without the preincubation period (5.8 ng/ml). When the indomethacin preincubation period was used, a significant increase in IL-6 production was found with 10(-9) M PGE2 (P < 0.005), and 10(-6) M PGE2 caused the production of 39.9 ng/ml IL-6 over 6 h. Stripping endocranial and ectocranial membranes from bones demonstrated the membranes to be the major site of IL-6 production. However, intact bones were required for maximal stimulated IL-6 production.

Animals↗
PubMed1994

Fatal graft-versus-host disease associated with transfusions of HLA-matched, HLA-homozygous platelets from unrelated donors.

BACKGROUND: Transfusion-associated graft-versus-host disease (TA-GVHD) due to blood from HLA-homozygous related and unrelated blood donors has been described. CASE REPORT: Fatal TA-GVHD due to the transfusion of HLA-matched platelets from an unrelated HLA-homozygous donor is reported. A 61-year-old man with a history of diabetes mellitus and myelodysplastic syndrome was diagnosed with acute myelogenous leukemia in November 1991. Induction chemotherapy resulted in aplasia, which was followed by a normocellular marrow with mild dysplasia and continued karyotypic abnormalities. High-dose chemotherapy was given in a second attempt to achieve complete remission. HLA-matched platelets were ordered when platelet refractoriness developed. The patient was HLA-heterozygous for HLA-A and -B antigens (A2, 29; B37, 44). Over the next 7 days, four unirradiated HLA-matched plateletpheresis units were transfused; one was probably homozygous for both HLA-A and -B antigens (A2, -; B44, -) and was transfused first, and three were probably homozygous for an HLA-B antigen (A2, 29; B44, -) and were white cell reduced. No blood relatives served as donors. Seven days after the first HLA-matched platelet transfusion, fever, chills, and diarrhea developed; 2 days later, a rash was present. Liver enzymes increased markedly. Renal and respiratory failure ensured. A skin biopsy was consistent with GVHD. Despite immunosuppressive therapy, the patient died 19 days after the first HLA-matched platelet transfusion. CONCLUSION: TA-GVHD has been recognized in immunocompromised, HLA-heterozygous patients receiving blood from blood relatives who are HLA-homozygous. patients receiving blood from either blood relatives or non-blood relatives who are HLA-homozygous. This HLA-heterozygous patient received transfusions of unirradiated, class I HLA-homozygous platelets, which were specifically ordered as HLA-matched, and his death was attributed to TA-GVHD. Consideration should always be given to providing irradiated blood for immunosuppressed patients, especially when HLA-matched platelets are used, to prevent TA-GVHD.

Blood Donors↗
PubMed1994

Characteristics of abstinent substance abusers who first sought treatment in adolescence.

A survey was given to 141 male and female substance abusers who had eleven or more months of continuous abstinence and first sought treatment in adolescence in an attempt to add to the limited knowledge of known variables associated with successful adolescent response to clinical and community-based treatment. Results were used to create a composite of successfully abstinent adolescents. Generally, parental alcoholism and most drug use patterns were not related to the number of relapses or length of sobriety. Most of the respondents entered twelve-step programs via treatment. The only two variables that were significantly correlated with the dependent measures of more relapses and less overall sobriety were getting high for the first time at a younger age and polydrug abuse. There were about five times more adoptees represented in this sample than would be statistically expected. Implications for adolescent substance abuse diagnosis and prognosis are discussed.

Adolescent↗
PubMed1993

Osteoclast recruitment in mice is stimulated by (3-amino-1-hydroxypropylidene)-1,1-bisphosphonate.

Though some evidence suggests that bisphosphonates (BPs) act directly on osteoclasts to inhibit bone resorption, other evidence suggests that they inhibit the development of the osteoclast. We found an increase in osteoclast recruitment in 2-day-old mice given (3-amino-1-hydroxypropylidene)-1,1-bisphosphonate (APD). A threefold increase in 5-bromo-2'-deoxyuridine (BrdU)-labeled osteoclast nuclei was observed on mouse parietal bones 3 days after APD injection. This suggests that inhibition of osteoclast development is not an action of APD in mice of this age. The mechanism of the increased recruitment was investigated. As osteoclast progenitors were not detected on parietal bones in vitro, we looked for an increase in circulating monocytes to account for the recruitment. No such increase was found, but when 51Cr-labeled bone marrow was injected intraperitoneally into mice given APD there was an increase in accumulation of 51Cr in calvaria and in femur and tibia over controls. This increase did not occur when 51Cr-labeled erythrocytes or free 51Cr was injected. We conclude that APD causes increased recruitment of osteoclast precursors by increasing the avidity of bone for hematopoietically derived cells.

Animals↗
PubMed1993

Requests for medications during chemical dependency rehabilitation as a predictor of relapse.

This study tested an aspect of the low-frustration-tolerance hypothesis by investigating the relationship between nonprescription medication requests by chemical-dependency patients, while in treatment, and their relapse rate. Subjects were 200 adult, chemically dependent patients admitted to a 28-day inpatient treatment program. The number of requests for nonprescription medications for subjective and objective symptoms were recorded for all patients during the course of their treatment, and these patients were followed for 1 year after treatment to determine if they had remained abstinent. Results were consistent with the predictions of the low-frustration-tolerance hypothesis. Patients who requested more medications for subjective symptoms during treatment were less likely to remain abstinent for 1 year after treatment.

Adult↗
PubMed1993

Localisation of vitronectin receptor immunoreactivity and tartrate resistant acid phosphatase activity in synovium from patients with inflammatory or degenerative arthritis.

The influx of cells into the synovial intima in rheumatoid joints may include osteoclasts and their precursors. The distribution of osteoclast markers--namely, tartrate resistant acid phosphatase activity and the expression of vitronectin receptor (shown with monoclonal antibodies 13C2 and 23C6)--was therefore examined in synovium obtained from patients with rheumatoid (RA) or degenerative (OA) arthritis. Tartrate resistant acid phosphatase positive cells were found in frozen sections of 60% (n = 30) of RA and 69% (n = 29) of OA synovial membranes. Whereas all synovia tested (four RA, four OA) showed diffuse staining of the lining cells with 13C2, 55% (n = 11) of RA and 57% (n = 14) of OA synovial membranes contained isolated cells stained with 23C6 scattered throughout the tissue. In cultures of synovial cells, tartrate resistant acid phosphatase positive, multinuclear, and 23C6 positive cells were found; these cells did not, however, form resorption pits on bone slices. The results show that fully differentiated osteoclasts are uncommon in synovium from patients with either degenerative or inflammatory arthropathies.

Acid Phosphatase↗
PubMed1993

Homogeneous versus heterogeneous age group treatment of adolescent substance abusers.

The treatment outcome from homogeneous age group substance abuse treatment centers, whose clientele consisted primarily of adolescent substance abusers, was compared to heterogeneous age group substance abuse treatment centers, where adolescent and adult patients were treated together. Subjects were 100 substance abusers, from 20 states, who recovered in adolescence and had at least 11 months of continuous abstinence. A 24-item self-report questionnaire was used to ascertain the type of recovery treatment experienced, number of relapses, and duration of sobriety. Results indicated a disproportionate number of substance abusers who recovered in adolescence were treated in a heterogeneous age group clinical setting. There was no significant difference in the length of sobriety and number of relapses between the homogeneous and heterogeneous treatment groups. These data suggest adolescent substance abusers can be treated at a lower cost and with a higher recovery rate by placing them in adult treatment settings.

Adolescent↗
PubMed1993

Treatment paternalism in chemical dependency counselors.

This study investigated the degree of paternalism in the treatment philosophies of chemical dependency counselors in three categories of treatment center: adolescent-only, adult, and religious/minority. Counselors were shown picture arrays of either adolescent patients or adult patients and asked to choose a preferred treatment policy, either paternalistic or compensatory in nature. Results showed religious/minority counselors preferred a significantly greater paternalistic approach to all patients than did the adolescent-only and adult center counselors. The adolescent-only counselors responded more paternalistically to the adolescent patients than the adult patients, while the adult and religious/minority counselors did not respond significantly different to either group.

Adolescent↗
PubMed1993

Self-feeding performance in nursing home residents.

In a study of cognitively impaired nursing home residents, excess disability was found in the specific mealtime task of drinking liquids and among those eating a puréed diet. Nursing home staff tended to rely on spoonfeeding, a process in which the resident is a passive recipient of care rather than an active participant in it, as an intervention among residents who were partially able to feed themselves. Feeding techniques other than spoonfeeding--including verbal and nonverbal prompts, and physical guiding--can support residents' participation in feeding even when independence is no longer possible.

Aged↗
PubMed1992

Institutionalized elderly. Relaxation, locus of control, self-esteem.

Progressive relaxation significantly moved elders toward a perception of internal locus of control. Progressive relaxation and activity programs significantly increased elders' self-esteem. Progressive relaxation was significantly more effective than the activity group in increasing self-esteem. Changes in locus of control and self-esteem were not correlated.

Aged↗
PubMed1991

An immunocytochemical method for studying the kinetics of osteoclast nuclei on intact mouse parietal bone.

An immunocytochemical method using an antibody against 5-bromo-2'-deoxyuridine has been applied to the study of the kinetics of osteoclast nuclei on intact mouse parietal bones. Osteoclasts containing tartrate-resistant acid phosphatase show nuclei that are positive for the thymidine analogue within 24 hours of injection into four-day old mice. Labelled osteoclast nuclei decline in number with a half-life of 1.3 days, compatible with a random mechanism of cell death rather than a fixed lifespan. This is shorter than has previously been reported and the possible reasons for this are suggested. The main advantages compared with autoradiography are the shortened processing time and the large number of osteoclasts that can be examined per parietal bone.

Animals↗
PubMed1990

Effects of (3-amino-1-hydroxypropylidene)-1,1-bisphosphonate on mouse osteoclasts.

A group of 5-day-old mice were injected intraperitoneally with (3-amino-1-hydroxypropylidine)-1,1-bisphosphonate (APD). Morphologic changes were observed in vitally stained osteoclasts on parietal bones 3 days later, and these were judged to be degenerative. At this time significantly increased numbers of nuclei per osteoclast and total numbers of osteoclast nuclei were observed. However, at 4 days after the injection of APD, the total numbers of osteoclasts were significantly reduced relative to controls. When parietal bones were maintained in culture, APD reduced osteoclast numbers and inhibited cell-mediated 45Ca2+ release. Exposure of bones to parathyroid hormone increased the number of osteoclasts counted 1 day later. This effect was not blocked by APD. Calcitonin prevented the reduction in osteoclast numbers due to APD in vitro. We conclude that APD has a direct effect on resorbing mouse osteoclasts.

Animals↗
PubMed1989

Time perception and the Stroop task.

Three experiments were conducted to assess the effects of the Stroop task (color-word incongruities) on observers' estimates of 30-sec. inspection periods. The experiments differed in psychophysical procedure; the three classic methods of production, reproduction, and verbal estimation were employed. Observers underestimated the passage of time, compared to doing nothing, when they were engaged on the Stroop task. However, judgments of duration on the Stroop task were shorter than those made in the control condition of naming color dots only when the method of production was employed. These findings are similar to results with mental arithmetic tasks and contribute to the understanding of the relationship between cognitive processing and time perception.

Adult↗