Publications by authors named "Johnstone B"

Rural residents with brain injury have difficulty in accessing care from qualified psychologists for consequent cognitive, emotional and behavioural symptoms. We examined high-quality videoconferencing to enhance care for persons with brain injury in three areas: cognitive assessment, psychotherapy and rural mental health training. The assessment study evaluated 52 outpatients seen for diagnostic visits over videoconferencing, and compared their experiences with those of 52 age- and diagnosis-matched controls seen in person.

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Green tea polyphenol-(-)epigallocatechin-3-gallate (EGCG)-is a potent chemopreventive agent in many test systems and has been shown to inhibit tumor promotion and induce apoptosis. In this study we describe a novel observation that EGCG displayed strong inhibitory effects on the proliferation and viability of HTB-94 human chondrosarcoma cells in a dose-dependent manner and induced apoptosis. Investigation of the mechanism of EGCG-induced apoptosis revealed that treatment with EGCG resulted in DNA fragmentation, induction of caspase-3/CPP32 activity, and cleavage of the death substrate poly(ADP-ribose)polymerase (PARP).

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This study investigated the relationships between antipsychotic drug use patterns and direct costs for 3,321 Medi-Cal patients with schizophrenia. Ordinary least-squares regression models were used to estimate the impact on costs of receiving antipsychotic drug treatment, delays in treatment, changes in therapy, and continuous therapy. Average costs were $25,940 per year per patient.

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Four sequential bone-marrow aspirations from the ipsilateral tibia and iliac crest of New Zealand White rabbits, aged 4 months or 1, 2, or 3 years, were assayed in vitro and in vivo for their chondro-osteogenic potential. Nonhematopoietic cells from the samples of bone marrow were isolated and expanded in culture; their colony-forming efficiency was determined, and second-passage marrow-derived cells, referred to as mesenchymal progenitor cells, were loaded into porous calcium-phosphate ceramic cubes as carrier vehicles for an in vivo cartilage and bone-formation assay. The cubes were placed subcutaneously in nude BALB/C mice for 3 and 6 weeks.

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Objective: To assess the chondrogenic potential of cells within the synovium.

Methods: Explants of synovium taken from various sites in the joint were embedded in agarose and cultured with transforming growth factor beta1 (TGFbeta1) to assess their chondrogenic potential. Isolated synovial cells were also tested for their chondrogenic potential by culturing them as aggregates in a chemically defined medium with TGFbeta1.

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The aim of this study was to investigate the potential of a composite matrix, containing esterified hyaluronic acid and gelatin, to facilitate the osteochondral differentiation of culture-expanded, bone marrow-derived mesenchymal progenitor cells. The cell loading characteristics and the effects of the matrix on cell differentiation were examined in vitro and in vivo. Empty and cell-loaded composites were cultivated for up to 28 days in a chemically defined medium with or without transforming growth factor-beta1 (TGF-beta1).

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The rabbit has been extensively used for preclinical models, especially in orthopedic applications. One of the more troubling features of this model is the high interindividual variability that is encountered and that requires a careful experimental design with sufficient sample size to make judgments valid. We have processed 241 individual preparations of rabbit bone marrow-derived mesenchymal progenitor cells (MPCs) over the last 3 years and have kept detailed records of the performance of these cells in various assays.

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Carbon monoxide (CO) poisoning is associated with variable neuropsychological deficits, depending on levels of CO exposure and individual differences. Studies to date have reported variable findings, as their subjects have been exposed to different levels of CO from different poisoning sources. Four unique case studies are presented, all of whom experienced the same level of CO poisoning (17-29%) in the same accident.

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The lack of repair of articular cartilage where the damage does not penetrate the subchondral bone indicates the importance of marrow components in the repair of the articular cartilage. In adult animals, there is an inability of articular cartilage chondrocytes to heal chondral defects, but if the damage extends beyond the subchondral bone, a repair process ensues in which mesenchymal progenitor cells migrate into the injured site and undergo chondrogenic differentiation. However, analysis of animal models and human biopsy samples indicates that fibrocartilage, rather than true articular cartilage is the predominant tissue synthesized.

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Altered growth and function of synoviocytes, the intimal cells which line joint cavities and tendon sheaths, occur in a number of skeletal diseases. Hyperplasia of synoviocytes is found in both rheumatoid arthritis and osteoarthritis, despite differences in the underlying aetiologies of the two disorders. We have studied the autosomal recessive disorder camptodactyly-arthropathy-coxa vara-pericarditis syndrome (CACP; MIM 208250) to identify biological pathways that lead to synoviocyte hyperplasia, the principal pathological feature of this syndrome.

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Era is a small G-protein widely conserved in eubacteria and eukaryotes. Although essential for bacterial growth and implicated in diverse cellular processes, its actual function remains unclear. Several lines of evidence suggest that Era may be involved in some aspect of RNA biology.

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We utilize data from a large, double-blind, randomized clinical trial of treatment for schizophrenia to compare the effect of therapy with the second generation antipsychotic olanzapine versus therapy with the conventional agent haloperidol on the perceived functioning and well-being of patients over 1 year as measured by the Medical Outcome Study Short Form (SF-36). We also compare the total cost of care between the treatment groups over 1 year and combine cost and functional outcomes information to estimate the incremental cost-effectiveness of both therapies in this sample. Over 1 year of therapy, patients receiving olanzapine experienced a mean of 5.

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Background: Although the results of many clinical studies suggest that breast-fed children score higher on tests of cognitive function than do formula-fed children, some investigators have suggested that these differences are related to confounding covariables such as socioeconomic status or maternal education.

Objective: Our objective was to conduct a meta-analysis of observed differences in cognitive development between breast-fed and formula-fed children.

Design: In this meta-analysis we defined the effect estimate as the mean difference in cognitive function between breast-fed and formula-fed groups and calculated average effects using fixed-effects and random-effects models.

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Bone marrow stromal cells isolated from a model of osteogenesis imperfecta (oim) mice, were transduced with a retrovirus (BAG) carrying the LacZ and neor genes after passage 21. The transduced cells retained the ability to express alkaline phosphatase activity in vitro when treated with recombinant human bone morphogenetic protein two (rhBMP-2), formed cartilage in vitro in aggregate cultures and formed bone in ceramic cubes after 6 weeks of implantation in nude mice. X-gal staining of ceramic cubes seeded with the transduced cells demonstrated the presence of LacZ-positive cells on the edges of bone and also in the lacunae of the newly formed bone 6 weeks after implantation.

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Unlabelled: Schizophrenia leads to impairments in mental, social, and physical functioning, which should be included in evaluations of treatment.

Objectives: This study was designed to determine the reliability and validity of the Medical Outcomes Study Short Form Health Survey (SF-36) for schizophrenic patients, to characterize perceived functioning and well being and to compare short-term change in SF-36 scores for patients treated with olanzapine or haloperidol.

Research Design: Data were obtained from a randomized, double-blind trial comparing these agents for safety, efficacy, and cost effectiveness.

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Objective: To determine the relationship among neuropsychological variables, vocational outcomes, and vocational costs for Missouri Division of Vocational Rehabilitation (MO-DVR) clients with traumatic brain injury (TBI).

Design: Clients referred for neuropsychological evaluations were followed until DVR case closure. Subjects were grouped according to the following DVR status at case closure: Successfully Employed, Services Interrupted, and No Services Provided.

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Adult marrow contains mesenchymal progenitor cells (MPCs) that have multiple differentiation potentials. A conditionally immortalized MPC clone, BMC9, has been identified that exhibits four mesenchymal cell phenotypes: chondrocyte, adipocyte, stromal (support osteoclast formation), and osteoblast. The BMC9 clone, control brain fibroblasts and another marrow-derived clone, BMC10, were isolated from a transgenic mouse (H-2Kb-tsA58) containing a gene for conditional immortality.

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Objective: To describe antipsychotic medication use patterns in an inner-city, outpatient population of indigent patients with schizophrenia.

Methods: This retrospective cohort study used the Regenstrief Medical Record System to identify schizophrenic patients receiving antipsychotic medication(s). Patients were included and identified as initiating a new treatment episode if they did not receive any antipsychotic prescription for 90 days before their first antipsychotic prescription in 1995.

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Background: Health plans commonly face the conflicting demands of trying to provide access to novel technologies, including new classes of medications, while trying to contain costs. These demands are particularly acute for California's Medicaid program, known as Medi-Cal, which is responsible for delivery of medical care to an unusually large population of mentally ill individuals in the context of a culturally diverse environment. To meet the challenge, Medi-Cal has instituted a formal process for technology assessment of new and existing pharmaceutical products known as the Therapeutic Class Review (TCR).

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Study Design: Posterolateral spinal fusion with autologous bone marrow aspirate in addition to autograft iliac crest bone graft in a rabbit model.

Objective: To demonstrate that the addition of autologous bone marrow can have positive effects on bone formation and spinal fusion.

Summary Of Background Data: Bone marrow has been shown to contain osteoprogenitor cells.

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The repair of a fracture necessarily entails synthesis of osseous tissue requiring the transformation of undifferentiated osteochondral progenitor cells to mature osteoblasts and chondrocytes. Owen and Friedenstein proposed that there are stem cells for all mesenchymal tissues, resident in bone marrow throughout life, that have a lineage comparable to that described for hematopoiesis. Subsequent with this initial study, marrow derived and periosteal derived progenitor cells have been shown to produce bone and cartilage in numerous in vivo and in vitro studies.

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Mesenchymal progenitor cells provide a source of cells for the repair of musculoskeletal tissue. However, in vitro models are needed to study the mechanisms of differentiation of progenitor cells. This study demonstrated the successful induction of in vitro chondrogenesis with human bone-marrow-derived osteochondral progenitor cells in a reliable and reproducible culture system.

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Increasing age is associated with greater absolute neuropsychological impairment (e.g. slower processing speed, diminished memory), although it is unclear if older individuals with traumatic brain injury (TBI) show greater relative impairment than younger individuals with TBI.

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A culture system that facilitates the chondrogenic differentiation of rabbit bone marrow-derived mesenchymal progenitor cells has been developed. Cells obtained in bone marrow aspirates were first isolated by monolayer culture and then transferred into tubes and allowed to form three-dimensional aggregates in a chemically defined medium. The inclusion of 10(-7) M dexamethasone in the medium induced chondrogenic differentiation of cells within the aggregate as evidenced by the appearance of toluidine blue metachromasia and the immunohistochemical detection of type II collagen as early as 7 days after beginning three-dimensional culture.

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