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21.
A case of reflex sympathetic dystrophy is presented in a 12-year-old girl with comorbid conversion disorder. Her identical twin also had a conversion disorder. This is the first reported case of coexistence of reflex sympathetic dystrophy and conversion disorder. It is important for clinicians to be aware that these conditions may coexist since the presentation of symptoms differ, even though there are shared features of treatment. 相似文献
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Alison E M Vickers Muriel Saulnier Elba Cruz Marjolijn T Merema Kristine Rose Philip Bentley Peter Olinga 《Toxicological sciences》2004,82(2):534-544
Liver slice viability is extended to 96 h for rat, expanding the use of this in vitro model for studying mechanisms of injury and repair, including pathways of fibrosis. The contributing factors to increased organ slice survival consist of the use of a preservation solution for liver perfusion and slice preparation, obtaining rats that are within the weight range of 250-325 g, placing a cellulose filter atop the titanium mesh roller-insert to support the slice, and maintaining the slices in an optimized culture medium which is replaced daily. The liver slices remain metabolically active, synthesizing adenosine triphosphate (ATP), glutathione, and glycogen, and exhibit preserved organelle integrity and slice morphology. Slice preparation results in 2-cut surfaces which likely triggers a repair and regenerative response. The fibrogenic pathways are evident by the activation of stellate cells, the proliferation of myofibroblast-like cells, and an increased collagen deposition by 48 h. Markers indicative of activated stellate cells, alpha-smooth muscle actin, collagen 1a1, desmin, and HSP47 are substantiated by real time-PCR. Increased staining of alpha-smooth muscle actin initially around the vessels and by 72-96 h in the tissue is accompanied by increased collagen staining. Microarray gene expression revealed extracellular matrix changes with the up-regulation of cytoskeleton, filaments, collagens, and actin genes; and the down-regulation of genes linked with lipid metabolism. The improvements in extending liver slice survival, in conjunction with its three-dimensional multi-cellular complexity, increases the application of this in vitro model for investigating pathways of injury and repair, and fibrosis. 相似文献
25.
Leschziner G Jorgensen AL Andrew T Pirmohamed M Williamson PR Marson AG Coffey AJ Middleditch C Rogers J Bentley DR Chadwick DW Balding DJ Johnson MR 《Lancet neurology》2006,5(8):668-676
BACKGROUND: The ABCB1 3435C-->T single-nucleotide polymorphism (SNP) or a three-SNP haplotype containing 3435C-->T has been implicated in multidrug resistance in epilepsy in three retrospective case-control studies, but a further three have failed to replicate the association. We aimed to determine the effect of the ABCB1 gene on epilepsy drug response, using a unique large cohort of epilepsy patients with prospectively measured seizure and drug response outcomes. METHODS: The ABCB1 3435C-->T polymorphism and three-SNP haplotype, plus a comprehensive set of tag SNPs across ABCB1 and adjacent ABCB4, were genotyped in a cohort of 503 epilepsy patients with prospectively measured seizure and drug response outcomes. Clinical, demographic, and genetic data were analysed. Treatment outcome was measured in terms of time to 12-month remission, time to first seizure, and time to drug withdrawal due to inadequate seizure control or side-effects. Randomly selected genome-wide HapMap SNPs (n=129) were genotyped in all patients for genomic control. FINDINGS: Number of seizures before treatment was the dominant feature predicting seizure outcome after starting antiepileptic drug therapy, measured by both time to first seizure (hazard ratio 1.34, 95% CI 1.21-1.49, p<0.0001) and time to 12-month remission (0.83, 0.73-0.94, p=0.003). There was no association of the ABCB1 3435C-->T polymorphism, the three-SNP haplotype, or any gene-wide tag SNP with time to first seizure after starting drug therapy, time to 12-month remission, or time to drug withdrawal due to unacceptable side-effects or to lack of seizure control. INTERPRETATION: We found no evidence that ABCB1 common variation influences either seizure or drug withdrawal outcomes after initiation of antiepileptic drug therapy. 相似文献
26.
Human acute leukemia cell line with the t(4;11) chromosomal rearrangement exhibits B lineage and monocytic characteristics 总被引:18,自引:8,他引:18
A cell line, designated RS4;11, was established from the bone marrow of a patient in relapse with an acute leukemia that was characterized by the t(4;11) chromosomal abnormality. The cell line and the patient's fresh leukemic cells both had the t(4;11)(q21;q23) and an isochromosome for the long arm of No. 7. Morphologically, all cells were lymphoid in appearance. Ultrastructurally and cytochemically, approximately 30% of the cells possessed myeloid features. The cells were strongly positive for terminal deoxynucleotidyl transferase. They were HLA-DR positive and expressed surface antigens characteristic for B lineage cells, including those detected by anti-B4, BA-1, BA-2, and PI153/3. Immunoglobulin gene analysis revealed rearrangements of the heavy chain and kappa chain genes. The cells lacked the common acute lymphoblastic leukemia antigen and antigenic markers characteristic of T lineage cells. The cells reacted with the myeloid antibody 1G10 but not with other myeloid monoclonal antibodies. Treatment with 12-O-tetradecanoyl- phorbol-13-acetate induced a monocyte-like phenotype demonstrated by cytochemical, functional, immunologic, and electron microscopic studies. The expression of markers of both early lymphoid and early myeloid cells represents an unusual phenotype and suggests that RS4;11 represents a cell with dual lineage capabilities. To our knowledge, RS4;11 is the first cell line established from t(4;11)-associated acute leukemia. 相似文献
27.
Use of multiple T cell-directed intact ricin immunotoxins for autologous bone marrow transplantation 总被引:7,自引:0,他引:7
The monoclonal antibodies (MoAb) T101, G3.7, 35.1, and TA-1 were conjugated to intact ricin using a thioether linkage. These MoAb detect, respectively, the CD5[gp67], CD7[p41], CD2[p50], and [gp95, 170] determinants that are found in the vast majority of cases of T cell acute lymphocytic leukemia (T-ALL). The resulting immunotoxins (ITs) and an equimolar mixture of these ITs were evaluated as potential purgative reagents for autologous transplantation in T-ALL. Leukemic cell lines were used to compare the kinetics of protein synthesis inactivation mediated by each IT. The cells were treated with IT in the presence of lactose in order to block the native binding of ricin. The observed rates of protein synthesis inactivation correlated with target antigen expression detected by fluorescence-activated cell sorter analysis. Of the four ITs, T101-ricin (T101-R) exhibited the fastest rate of inactivation, followed in order by G3.7-ricin, TA-1-ricin, and 35.1-ricin. At concentrations greater than 300 ng/mL, a cocktail containing an equimolar amount of all four ITs (referred to as the four- IT cocktail) exhibited kinetics that were as fast or faster than those of T101-R. The long-term cytotoxic effects of individual ITs and the four-IT cocktail were evaluated using a sensitive clonogenic assay. Each IT was specifically cytotoxic and inhibited 1 to 4 logs of clonogenic leukemic cells at doses (300 to 600 ng/mL) that can be used clinically. The four-IT cocktail was highly cytotoxic; a concentration of 300 ng/mL inhibited greater than 4 logs of leukemic cells while sparing the majority of committed (CFU-GM, CFU-E) and pluripotent (CFU- GEMM) hematopoietic stem cells. The determination of both short-term kinetics of protein synthesis inactivation and longer-term inhibition of clonogenic growth allowed new insight into cell killing by IT. Our results suggest that ITs continue to act on clonogenic target cells for a period of three to five days. Interestingly, the four-IT cocktail was not as potent against clonogenic leukemic cells as T101-R alone, although it exhibited kinetics of protein synthesis inhibition that were as fast as those of T101-R alone. This finding suggests that internalized ITs may differ in the length of time they remain active within the cell. Our results also demonstrate the importance of using several different assays to evaluate IT reagents. 相似文献
28.
Volker Alt Simon T. Donell Amit Chhabra Anthony Bentley Alexander Eicher Reinhard Schnettler 《Injury》2009,40(12):1269-1275
The purpose of this study was to determine the cost savings from a societal perspective for recombinant human Bone Morphogenetic Protein-2 (rhBMP-2) in grade III A and B open tibial fractures treated with a locked intramedullary nail and soft-tissue management in the UK, Germany, and France. Health care system costs (direct health care costs) and costs for productivity losses (indirect health care costs) were calculated using the raw data from the Bone Morphogenetic Protein Evaluation Group in Surgery for Tibial Trauma “BESTT study”. Return-to-work time for estimation of productivity losses was assumed to correspond with the time of fracture healing. For calculation of secondary interventions costs and productivity losses the respective 2007/2008 national tariffs for surgical procedures and average national wages for the UK, Germany, and France were used. For a 1 year perspective, overall treatment costs per patient after the initial surgery of the control vs. the rhBMP-2 group were €44,757 vs. €36,847 for the UK, €50,197 vs. €40,927 for Germany and €48,766 vs. €39,474 for France in favour of rhBMP-2 with overall savings overall savings per case of rhBMP-2 treatment of €7911 for the UK, €9270 for Germany, and €9291 for France which was mainly due to reduced productivity losses by significant faster fracture healing in the rhBMP-2 group (p = 0.01). These savings largely offset the upfront price of rhBMP-2 of €2266 (£1790) in the UK, €2970 in Germany, and €2950 in France. Total net savings can be estimated to be €9.6 million for the UK, €14.5 million for Germany, and €11.4 million for France. The results depend on the methodology used particularly for calculation of productivity losses and return-to-work time which was assumed to correspond with fracture healing time. In summary, despite the apparent high direct cost of rhBMP-2 in grade III A and B open tibial fractures, at a national level there are net cost savings from a societal perspective for all three countries. 相似文献
29.
Gonadotropin-inhibitory hormone neurons interact directly with gonadotropin-releasing hormone-I and -II neurons in European starling brain 总被引:3,自引:0,他引:3
Ubuka T Kim S Huang YC Reid J Jiang J Osugi T Chowdhury VS Tsutsui K Bentley GE 《Endocrinology》2008,149(1):268-278
Gonadotropin-inhibitory hormone (GnIH) is a hypothalamic dodecapeptide (SIKPSAYLPLRF-NH(2)) that directly inhibits gonadotropin synthesis and release from quail pituitary. The action of GnIH is mediated by a novel G-protein coupled receptor. This gonadotropin-inhibitory system may be widespread in vertebrates, at least birds and mammals. In these higher vertebrates, histological evidence suggests contact of GnIH immunoreactive axon terminals with GnRH neurons, thus indicating direct regulation of GnRH neuronal activity by GnIH. In this study we investigated the interaction of GnIH and GnRH-I and -II neurons in European starling (Sturnus vulgaris) brain. Cloned starling GnIH precursor cDNA encoded three peptides that possess characteristic LPXRF-amide (X = L or Q) motifs at the C termini. Starling GnIH was further identified as SIKPFANLPLRF-NH(2) by mass spectrometry combined with immunoaffinity purification. GnIH neurons, identified by in situ hybridization and immunocytochemistry (ICC), were clustered in the hypothalamic paraventricular nucleus. GnIH immunoreactive fiber terminals were present in the external layer of the median eminence in addition to the preoptic area and midbrain, where GnRH-I and GnRH-II neuronal cell bodies exist, respectively. GnIH axon terminals on GnRH-I and -II neurons were shown by GnIH and GnRH double-label ICC. Furthermore, the expression of starling GnIH receptor mRNA was identified in both GnRH-I and GnRH-II neurons by in situ hybridization combined with GnRH ICC. The cellular localization of GnIH receptor has not previously been identified in any vertebrate brain. Thus, GnIH may regulate reproduction of vertebrates by directly modulating GnRH-I and GnRH-II neuronal activity, in addition to influencing the pituitary gland. 相似文献
30.
Suppression of apoptosis in hematopoietic factor-dependent progenitor cell lines by expression of the FAC gene 总被引:2,自引:5,他引:2
Fanconi anemia (FA) is a genetically heterogeneous, inherited blood disorder characterized by bone marrow failure, congenital malformations, and a predisposition to leukemias. Because FA cells are hypersensitive to DNA cross-linking agents and have chromosomal instability, FA has been viewed as a disorder of DNA repair. However, the exact cellular defect in FA cells has not been identified. Sequence analysis of the gene defective in group C patients (FAC) has shown no significant homologies to other known genes. The FAC protein has been localized to the cytoplasm, indicating that FAC may either play an indirect role in DNA repair or is involved in a different cellular pathway. Recent evidence has indicated that FA cells may be predisposed to apoptosis, especially after treatment with DNA cross-linking agents. The demonstration that genes can suppress apoptosis has been accomplished by overexpression of such genes in growth factor-dependent cell lines that die by apoptosis after factor withdrawal. Using retroviral-mediated gene transfer, we present evidence that expression of FAC in the hematopoietic factor-dependent progenitor cell lines 32D and MO7e can suppress apoptosis induced by growth factor withdrawal. Flow cytometry and morphologic analysis of propidium iodide stained cells showed significantly lower levels of apoptosis in FAC-retroviral transduced cells after growth factor deprivation. Expression of FAC in both cell lines promoted increased viability rather than proliferation, which is consistent with other apoptosis-inhibiting genes such as Bcl- 2. These findings imply that FAC may act as a mediator of an apoptotic pathway initiated by growth factor withdrawal. Furthermore, the congenital malformations and hematologic abnormalities characterizing FA may be related to an increased predisposition of FA progenitor cells to undergo apoptosis, particularly in the absence of extracellular signals. 相似文献