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51.
Actin cytoskeletal polymerization is associated with a pro-proliferative, pro-survival state. We hypothesized that the actin polymerization of wound cells is increased in the presence of wound matrix attachment and is decreased after disruption of this attachment. Musculocutaneous flap and wound splinting models were used to investigate the effect of wound matrix attachment on the actin cytoskeleton. Disruption of wound matrix attachment was accomplished by incision of the wound matrix/dermis interface (wound matrix release) and/or desplinting. Polymerized actin was assayed with phalloidin labeling of wound specimens 24 hours after disruption of attachment and a method to quantify the content and organization of polymerized actin in granulation tissue was used. Disruption of wound matrix attachment decreased the content of polymerized actin, the actin staining intensity, and the actin fiber organization in the granulation tissue of both the flap and splint models. Disruption of wound matrix attachment decreased actin polymerization and fiber organization in the granulation tissue. Our data support the concept that the state of wound matrix attachment regulates the actin cytoskeleton of wound cells. 相似文献
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BACKGROUND: Production of grammatical morphology is typically impaired in agrammatic aphasic individuals, as is their capacity to produce the syntactic structure responsible for licensing that morphology. Whether these two impairments are causally related has been an issue of long-standing debate. If morphological deficits are a side-effect of underlying syntactic ones, as has been claimed (Friedmann & Grodzinsky, 1997; Izvorski & Ullman, 1999), therapy which improves the syntactic deficit should remediate the morphological deficit as well. This paper reports a case study of one individual with such co-occurring impairments and describes their recovery in response to linguistically-motivated treatment targeting his syntactic deficits. METHODS #ENTITYSTARTX00026; PROCEDURES: MD is a 56 year-old male diagnosed with non-fluent Broca's aphasia subsequent to a left-hemisphere CVA, with limited capacity to produce syntactically complex utterances and grammatical morphology. He was enrolled in therapy using Treatment of Underlying Forms (TUF; Thompson & Shapiro, 2005), targeting production of sentences involving Wh-movement (object relative clauses). MD participated in twice-weekly treatment sessions for approximately two months, with daily probes assessing his production of treated and untreated sentence types. In addition, probes assessing his grammatical morphology and sentence production were administered pre- and post-treatment. OUTCOMES #ENTITYSTARTX00026; RESULTS: Pre-treatment scores in tests of grammatical morphology and sentence production indicated deficits in both domains. During treatment, MD successfully acquired production of a variety of sentence with Wh-movement, though this did not generalize to sentences involving a grammatically distinct movement operation (NP-movement). Post-treatment scores also indicated a lack of improvement in production of grammatical morphology. CONCLUSIONS: The dissociation between MD's morphological and syntactic recovery indicates that the recovery of syntactic and morphological processes in aphasia may occur independently. This result is thus surprising under approaches in which morphological and syntactic impairments are strongly and causally related in aphasia, such as the Tree-Pruning Hypothesis (Friedmann, 2001; Friedmann & Grodzinsky, 1997). Further, these results reinforce the conclusion that aphasia treatment can lead to generalization, but only to linguistic material which is in a subset relation to trained structures (Thompson, Shapiro, Kiran & Sobecks, 2003). 相似文献
54.
Sean J. Barnett M.S. M.D. Christopher Stanley B.S. Melanie Hanlon R.N. C.N.P. Robert Acton M.D. Daniel A. Saltzman M.D. Ph.D. Sayeed Ikramuddin M.D. Henry Buchwald M.D. Ph.D. 《Surgery for obesity and related diseases》2005,1(4):1609-398
PURPOSE: Obesity has become a health-care crisis in the United States. Adolescent obesity is now one of the most common childhood disorders, with 4.7 million American adolescents having a body mass index (BMI) greater than the 95th percentile. Most patients do not respond to diet modification or exercise programs and attention is now turning toward surgery as a source of weight loss in adolescents. Few studies have looked at the overall morbidity and mortality of weight loss surgery in this patient population. METHODS: This is a retrospective study of medical charts of 15 bariatric surgical procedures performed on 14 adolescents without known genetic syndromes associated with severe childhood obesity from 1971 to 2001 at the University of Minnesota. Procedures performed on these patients included vertical banded gastroplasty (n = 7), Roux-en-Y gastric bypass (n = 5), and jejunoileal bypass (n = 3). Jejunoileal bypass procedures were performed from 1971 to 1977, after which time this procedure was abandoned. Patient age ranged from 13 to 17 years (mean, 15.7 years). Mean follow-up time was 6 years, with 9 patients available for long-term follow-up. RESULTS: All procedures were performed using an open technique by 1 surgeon. There were no perioperative deaths; complications included 1 case of wound infection, 2 episodes of dumping syndrome that resolved without revision, 1 episode of hypoglycemia, and 1 case of short-term electrolyte imbalance in a patient who underwent jejunoileal bypass. The average BMI dropped from 58.5 +/- 13.7 to 32.1 +/- 9.7 kg/m(2) (P < .01)--a 45% reduction. CONCLUSIONS: Surgery for morbid obesity is safe and results in significant weight loss in adolescents who fail medical therapy. 相似文献
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D. McDonald H. Deavall P. Moss† J. Steele† J. Thompson V. Turner 《Transfusion medicine (Oxford, England)》2006,16(S1):52-52
Over 20 years ago, the Birmingham Blood Centre established a facility for the cryopreservation of bone marrow (BM) for patients in the West Midlands suffering from haematopoietic disorders and for whom a bone marrow transplant was indicated. Today, the use of mobilised peripheral blood (PBSC) has overtaken bone marrow as the source of stem cells for transplantation and the numbers of patients benefitting and the diversity of conditions being treated has increased enormously. Allogeneic transplants, using stem cells from healthy donors, have become increasingly successful as a result of an improving understanding of the complexities of the HLA histocompatibility system. Additionally umbilical cord blood (HUC), which in the 1980s was recognised as a source of stem cells, can now be collected and used for transplantation. As scientific knowledge and the clinical management of patients has advanced, so too have laboratory methods for manipulating cell products to enrich or deplete certain cell populations (e.g. by CD34+cell selection) in order to minimise potentially fatal graft-versus-host disease (GVHD) or to eliminate tumour cells in the case of autologous patients. Donor lymphocytes (DLI) may also be collected and used to aid a graft-versus-leukaemia (GVL) effect. The laboratory is currently developing protocols for immunotherapy using virus-specific T cells which can be prepared and infused to combat potentially fatal CMV disease post-transplant. Clinical trials of vaccines employing tumour specific dendritic cells for treating patients with hepatocellular carcinoma (HCC) and metastatic melanoma (MM), which do not respond to conventional treatments, are also underway. The advances and expansion in the Stem Cell and Immunotherapy (SCI) service in Birmingham over the last 10 year period are reflected in the table below:
57.
Martina Ballmaier Elizabeth R Sowell Paul M Thompson Anand Kumar Katherine L Narr Helen Lavretsky Suzanne E Welcome Heather DeLuca Arthur W Toga 《Neuropsychopharmacology》2004,55(4):382-389
BACKGROUND: In elderly depression, volumetric brain imaging findings suggest abnormalities of the frontal lobe, particularly the orbitofrontal cortex, and the hippocampus. No studies to date have mapped cortical abnormalities over the entire brain surface in major depression. Here, we conducted detailed spatial analyses of brain size and gray matter within the cortical mantle in elderly patients with major depression. METHODS: High-resolution, three-dimensional, structural magnetic resonance imaging data and cortical pattern matching methods were used in 24 depressed elderly patients and 19 group-matched controls to measure local brain size and proportions of gray matter at thousands of homologous cortical surface locations. RESULTS: Prominent brain size reductions were observed in the depressed subjects in the orbitofrontal cortex bilaterally. Cortical gray matter measurements revealed significant gray matter increases in the orbitofrontal cortex, adjacent to focal trend level significant decreases of gray matter in the same region. Depressed patients also exhibited significant gray matter increases in parietal cortices, as well as the left temporal cortex. CONCLUSIONS: Complex cortical changes may contribute to the brain size reduction of the orbitofrontal cortex and to the gray matter abnormalities detected in orbitofrontal cortex and temporoparietal cortices, thereby providing a potentially new window into the pathophysiology of elderly depression. 相似文献
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59.
John S. Witte Giske Ursin Jack Siemiatycki W. Douglas Thompson Annali Paganini-Hill Robert W. Haile 《Breast cancer research and treatment》1997,42(3):243-251
We investigated associations between diet and premenopausal bilateral breast cancer in a familial matched case-control study. We studied 140 cases from population-based registries in Los Angeles County (California) and Connecticut, and from the major hospitals in the southern parts of the Province of Quebec. Unaffected sisters of the cases served as matched controls (222 total). Dietary intake were assessed with a food frequency questionnaire. Total fat, monounsaturated fat, polyunsaturated fat, oleic acid, and linoleic acid intake was inversely associated with premenopausal bilateral breast cancer risk. Consumption of carbohydrates (and sweetened beverages) was associated with an increased risk. We observed no associations for dietary fiber, antioxidants, or major food groupings, but we did observe inverse associations for intake of low fat dairy products and tofu. These findings suggest that monounsaturated and polyunsaturated fats, as well as soy foods, might reduce the risk of premenopausal bilateral breast cancer. 相似文献
60.