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1.
Desmoplastic malignant melanoma (DMM) is a rare variant of spindle cell melanoma. We report a case of DMM of the forehead secondarily involving the orbit. The diagnosis was based on light microscopic features, including prominent peripheral cell nest formation and spindle cell fascicles in densely collagenous stroma. Immunohistochemical studies showed strong uniform staining for S100 antigen throughout the tumour. It was negative for HMB 45, smooth muscle actin, desmin, cytokeratins and Type IV collagen. Electron microscopy showed neither melanosomes nor myelin figures. The clinical and histological characteristics of desmoplastic malignant melanoma, and its differential diagnosis of malignant schwannoma, are discussed. DMM has a poor prognosis, since it tends to invade deeply, recur locally and metastasise readily.  相似文献   
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The history and clinical findings are presented of a patient who suffered from the uveal effusion syndrome over a 10-year period from 1956. The funduscopic appearance is illustrated both at the time of initial presentation and 36 years later. This condition typically affects healthy middle-aged men and causes recurrent, spontaneous, serous retinal and ciliochoroidal detachments, often resulting in significant visual impairment. Two separate hypotheses have been postulated to explain the pathogenesis of the uveal effusion syndrome, one relating to abnormally thickened sclera, the other to chronic bulbar hypotony. Both are discussed, as is the rationale behind the current management of this unusual condition.  相似文献   
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Bone metastasis is a complication of prostate cancer in up to 90% of men afflicted with advanced disease. Therapies that reduce androgen exposure remain at the forefront of treatment. However, most prostate cancers transition to a state whereby reducing testicular androgen action becomes ineffective. A common mechanism of this transition is intratumoral production of testosterone (T) using the adrenal androgen precursor dehydroepiandrosterone (DHEA) through enzymatic conversion by 3β- and 17β-hydroxysteroid dehydrogenases (3βHSD and 17βHSD). Given the ability of prostate cancer to form blastic metastases in bone, we hypothesized that osteoblasts might be a source of androgen synthesis. RNA expression analyses of murine osteoblasts and human bone confirmed that at least one 3βHSD and 17βHSD enzyme isoform was expressed, suggesting that osteoblasts are capable of generating androgens from adrenal DHEA. Murine osteoblasts were treated with 100 nM and 1 μM DHEA or vehicle control. Conditioned media from these osteoblasts were assayed for intermediate and active androgens by liquid chromatography–tandem mass spectrometry. As DHEA was consumed, the androgen intermediates androstenediol and androstenedione were generated and subsequently converted to T. Conditioned media of DHEA-treated osteoblasts increased androgen receptor (AR) signaling, prostate-specific antigen (PSA) production, and cell numbers of the androgen-sensitive prostate cancer cell lines C4-2B and LNCaP. DHEA did not induce AR signaling in osteoblasts despite AR expression in this cell type. We describe an unreported function of osteoblasts as a source of T that is especially relevant during androgen-responsive metastatic prostate cancer invasion into bone. © 2021 American Society for Bone and Mineral Research (ASBMR). This article has been contributed to by US Government employees and their work is in the public domain in the USA.  相似文献   
5.
PURPOSE: The objective of this study was to further investigate the efficacy and safety of low-dose outpatient chemobiotherapy in patients with unresectable metastatic melanoma. PATIENTS AND METHODS: Thirty-one patients with histologically confirmed unresectable measurable metastatic melanoma were enrolled onto an open-label, multicenter phase II study. The treatment regimen consisted of oral temozolomide followed by subcutaneous biotherapy with granulocyte macrophage colony-stimulating factor, interferon-alfa, and recombinant interleukin-2 (rIL-2). RESULTS: Twenty-eight patients (90%) had M1c disease, and 58% had three or more sites of metastasis. Four patients (13%), all with M1c disease, had a complete response, and four patients had a partial response. The median progression-free survival was 4.9 months and the median overall survival was 13.1 months. Two patients (6%) developed CNS metastasis as the first site of disease progression, and 7 (23%) of 30 experienced CNS progression after receiving chemobiotherapy. A total of 112 cycles of therapy were administered. Toxicity occurred in 78% of the cycles and was grade 1 or 2 in the majority of cases and easily managed. Grade 4 toxicity occurred in 3% of the cycles. CONCLUSION: This low-dose chemobiotherapy combination produces clinical responses in patients with metastatic melanoma, even in those with M1c disease, is well tolerated, and allows home dosing. It offers a reasonable alternative to high-dose regimens, such as high-dose biochemotherapy or rIL-2 requiring prolonged periods of hospitalization, or single agent outpatient regimens, such as dacarbazine, which is usually not effective in patients with M1c disease. Furthermore, it may protect against the development of brain metastases.  相似文献   
6.
Recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) clearly hastens myeloid recovery in patients with relapsed hematologic malignancies undergoing autologous bone marrow transplantation (ABMT). In efforts to further improve neutrophil engraftment and shorten hospital stay in ABMT patients, rhGM-CSF was administered by a potentially more potent route (continuous infusion) to non-Hodgkin's lymphoma (NHL) patients with better BM reserve (first remission). Time to myeloid engraftment was compared with that of NHL patients treated in first remission at our institution on a similar ABMT protocol but without growth factor support (controls). Median neutrophil engraftment (absolute neutrophil count, 500 cells/microL) in first remission patients treated with rhGM-CSF was 14 days, compared with 22 days in controls (P = .0001). Hospital stays were also significantly reduced for rhGM-CSF patients (P = .0003). Platelet engraftment did not differ between the two groups. Persistent fever and generalized serositis were the primary toxicities. rhGM-CSF, delivered by this route, was efficacious but more toxic than 2-hour rhGM-CSF infusions previously reported by other investigators. Future alterations in both dose and schedule may retain comparable efficacy yet diminish toxicity.  相似文献   
7.
Alpha-toxin (AT) is a major virulence determinant in Staphylococcus aureus skin and soft tissue infection models. We previously demonstrated that prophylactic administration of 2A3, an AT-neutralizing monoclonal antibody (MAb), prevents S. aureus disease in a mouse dermonecrosis model by neutralizing AT-mediated tissue necrosis and immune evasion. In the present study, MEDI4893*, an affinity-optimized version of 2A3, was characterized for therapeutic activity in the dermonecrosis model as a single agent and in combination with two frontline antibiotics, vancomycin and linezolid. MEDI4893* postinfection therapy was found to exhibit a therapeutic treatment window similar to that for linezolid but longer than that for vancomycin. Additionally, when combined with either vancomycin or linezolid, MEDI4893* resulted in reduced tissue damage, increased neutrophil and macrophage infiltration and abscess formation, and accelerated healing relative to those with the antibiotic monotherapies. These data suggest that AT neutralization with a potent MAb holds promise for both prophylaxis and adjunctive therapy with antibiotics and may be a valuable addition to currently available options for the treatment of S. aureus skin and soft tissue infections.  相似文献   
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BACKGROUND: People with physical and sensory disabilities face important challenges in obtaining high-quality health care. We examined whether persons who are blind or have low vision, who are deaf or hard of hearing, or who have mobility impairments or manual dexterity problems are satisfied with the technical and interpersonal aspects of their care. METHODS: By using a 1996 nationally representative survey of 16 403 community-dwelling elderly and disabled Medicare beneficiaries, we identified persons with disabling conditions. Adjusted odds ratios (AORs) and 95% confidence intervals (CIs) controlled for demographic characteristics and managed care membership in predicting dissatisfaction with 12 dimensions of care. RESULTS: Of an estimated 33.58 million noninstitutionalized Medicare beneficiaries, 64.1% (an estimated 21.51 million) reported at least 1 potential disability and 29.5% (an estimated 9.89 million) reported more than 1 potential disability. Roughly 98% of people with and without disabilities believed their physicians were competent and well trained. But statistically significantly more people with disabilities reported dissatisfaction with care for 10 of the 12 quality dimensions. Persons reporting any major disability were more likely to be dissatisfied with physicians completely understanding their conditions (AOR, 2.4; 95% CI, 1.9-3.1), physicians completely discussing patients' health problems (AOR, 2.4; 95% CI, 1.9-2.9), physicians answering all patients' questions (AOR, 2.3; 95% CI, 1.7-3.1), and physicians often seeming hurried (AOR, 1.6; 95% CI, 1.4-1.9). CONCLUSIONS: Persons with disabilities generally reported positive views of their care, although they were significantly more likely to report poor communication and lack of thorough care. These findings held regardless of the disabling condition. Thoughtful systematic approaches are required to improve communication and to reduce time pressures that might compromise the health care experiences of people with disabilities.  相似文献   
10.
One mechanism for transducing signals downstream of lymphocyte receptor activation involves the stable association between signaling proteins. To identify protein ligands of the signal activator phospholipase Cgamma1 (PLCgamma1), we screened T cell cDNA libraries with the PLCgamma1-SH3 domain by the yeast two-hybrid assay. We observed association between the PLCgamma1-SH3 domain and the human Ras guanine nucleotide exchange factor son-of-sevenless-2 (hSos2) through a proline-rich domain interaction. Stable and abundant hSos2 / PLCgamma1 and hSos1 / PLCgamma1 complexes were observed in unstimulated T cells. The interaction between these enzymes was augmented following engagement of the T cell antigen receptor (TCR / CD3). The kinetics of protein complex enhancement correlated with TCR / CD3-induced tyrosine phosphorylation of PLCgamma1; however, those PLCgamma1 molecules in complex with hSos2 were non-phosphorylated after TCR / CD3 stimulation, in contrast to the phosphorylated PLCgamma1 associated with the linker for activation of T cells, LAT. The Grb2 adapter protein was detected in complex with hSos / PLCgamma1, suggesting a regulatory role for Grb2. SH3 domains from both Grb2 and PLCgamma1, but not RasGAP, bound directly to hSos homologues. The SH2 domain from Grb2 formed an association with the hSos / PLCgamma1 complex, which was enhanced following TCR / CD3 ligation. Together, the data suggest a mechanism for the son-of-sevenless and PLCgamma1 signal transducing enzymes in recruitment to protein complexes with potentially differential signaling consequences in T lymphocytes.  相似文献   
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