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81.
OBJECT: Inhibition of remyelination is part of the complex problem of persistent dysfunction after spinal cord injury (SCI), and residual myelin debris may be a factor that inhibits remyelination. Phagocytosis by microglial cells and by macrophages that migrate from blood vessels plays a major role in the clearance of myelin debris. The object of this study was to investigate the mechanisms underlying the failure of significant remyelination after SCI. METHODS: The authors investigated macrophage recruitment and related factors in rats by comparing a contusion model (representing contusive SCI with residual myelin debris and failure of remyelination) with a model consisting of chemical demyelination by lysophosphatidylcholine (representing multiple sclerosis with early clearance of myelin debris and remyelination). The origin of infiltrating macrophages was investigated using mice transplanted with bone marrow cells from green fluorescent protein-transfected mice. The changes in levels of residual myelin debris and the infiltration of activated macrophages in demyelinated lesions were investigated by immunostaining at 2, 4, and 7 days postinjury. To investigate various factors that might be involved, the authors also investigated gene expression of macrophage chemotactic factors and adhesion factors. RESULTS: Activated macrophages coexpressing green fluorescent protein constituted the major cell population in the lesions, indicating that the macrophages in both models were mainly derived from the bone marrow, and that very few were derived from the intrinsic microglia. Immunostaining showed that in the contusion model, myelin debris persisted for a long period, and the infiltration of macrophages was significantly delayed. Among the chemotactic factors, the levels of monocyte chemoattractant protein-1 and granulocyte-macrophage colony-stimulating factor were lower in the contusion model at 2 and 4 days postinjury. CONCLUSIONS: The results suggest that the delayed infiltration of activated macrophages is related to persistence of myelin debris after contusive SCI, resulting in the inhibition of remyelination.  相似文献   
82.
Background A reliable marker of chemoradiosensitivity that would enable appropriate and individualized treatment of thoracic squamous cell esophageal cancer has long been sought. We investigated whether regenerating gene (REG) Iα is such a marker. Methods We assessed expression of REG Iα in untreated endoscopic biopsy specimens and examined the correlation between REG Iα expression and the clinical responses to definitive chemoradiotherapy and prognosis. We also examined the relationship between REG Iα expression in the resected tumor and the prognosis of patients who received esophagectomy for thoracic squamous cell esophageal cancer. Results Among the 42 patients treated with definitive chemoradiotherapy, 8 of the 23 REG I-positive patients (35%) showed complete responses to chemoradiotherapy, while only one of the 19 REG I-negative patients did so. The survival rate among the REG I-positive patients was significantly better than among the REG I-negative patients. For the 76 patients treated surgically, there was no significant difference in the survival rates among the REG I-positive and REG I-negative patients. Conclusions REG Iα expression in squamous cell esophageal carcinoma may be a reliable marker of chemoradiosensitivity. We anticipate that it will enable us to provide more appropriate and individualized treatment to patients of advanced esophageal squamous cell carcinoma.  相似文献   
83.
Objectives. To investigate the usefulness of digital rectal examination (DRE) and transrectal ultrasonography (TRUS) for prostate cancer diagnosis and to propose a diagnostic algorithm for individual-based cancer screening in subjects with prostate-specific antigen (PSA) levels of 4.0 ng/mL or less.Methods. Between January 1992 and March 2000, 129 subjects with PSA levels of 4.0 or less and abnormal findings on DRE or TRUS underwent prostate biopsy. The subjects were divided into four groups according to the PSA range: 0 to 0.9 ng/mL, 1.0 to 1.9 ng/mL, 2.0 to 2.9 ng/mL, and 3.0 to 4.0 ng/mL. The reliability of the DRE and TRUS and the clinicopathologic features of prostate cancer were investigated among these four groups.Results. Of the 129 subjects, 17 (13.2%) patients with prostate cancer were diagnosed. The detection rate was 2.2% (1 of 45), 0% (0 of 27), 20.6% (7 of 34), and 39.1% (9 of 23) in subjects with PSA levels of less than 1.0 ng/mL, 1.0 to 1.9 ng/mL, 2.0 to 2.9 ng/mL, and 3.0 to 4.0 ng/mL, respectively. The proportion of patients with Stage II, III, and IV was 58.8%, 41.2%, and 0%, respectively. The percentage with Gleason scores of 8 to 10 was 17.6%. The detection rate of abnormal findings on DRE and TRUS was 14.4% (13 of 90) and 9.5% (7 of 74), respectively. Adding TRUS to DRE in the screening program of subjects with PSA levels of 2.0 to 4.0 ng/mL, increased the detection rate of prostate cancer to 30.8% (4 of 13).Conclusions. Routine prostate biopsy should not be undertaken except for highly suspicious DRE findings in subjects with PSA levels less than 2.0 ng/mL. The additional use of TRUS in subjects with PSA levels of 2.0 to 4.0 ng/mL would improve the sensitivity of prostate cancer detection. The diagnostic algorithm proposed in the present study is useful as a screening method for prostate cancer in subjects with PSA levels of 4.0 ng/mL or less.  相似文献   
84.
A total of 548 upper limbs (276 right and 272 left hands) from Japanese cadavers were dissected. The arrangements of extensor indicis proprius, extensor digitorum communis (EDC), and extensor digiti minimi tendons and the intertendinous connections were studied. The most common pattern of extensor tendons was as follows: the index finger had a single EDC tendon, the middle finger had a single EDC tendon, the ring finger had a single EDC tendon, and the small finger had a single EDC tendon or a single common EDC tendon distributed to the ring and small finger. A single extensor indicis proprius tendon ran along the ulnar side of the EDC, and the extensor digiti minimi tendon consisted of 2 slips. Intertendinous connections were classified into 3 types: type 1 with a filamentous band, type 2 with a fibrous band, and type 3 with a tendinous band subdivided to r-shaped and y-shaped. The most common patterns were type 1 in the second intermetacarpal space (IMCS), type 3r in the third IMCS, and type 3y in the fourth IMCS.  相似文献   
85.
BACKGROUND: In this study, we report on the effectiveness and usefulness of two-staged gamma knife radiosurgery (GKS) for large petroclival and cavernous sinus meningiomas that have a high rate of surgical morbidity. METHODS: We have treated 7 patients suffering from large petroclival and cavernous sinus meningiomas using two-staged radiosurgery since March 1995. The tumors were located in the petroclival region in 4 patients, the cavernous sinus region in 2 patients, and in the petrocavernous region in the remaining patient. Three of the patients had been surgically treated and 4 patients (57%) were only followed with MR imaging. The volume of the tumors ranged between 34.5 to 101 cm(3) (mean 53.5 cm(3)). The treatment volume was between 6.8 to 29.6 cm(3) (mean 18.6 cm(3)). The treatment interval between the first GKS and second GKS was 6 months. The marginal doses for the tumors were 8 to 12 Gy (mean, 9 Gy). RESULTS: Six patients demonstrated tumor growth control during the follow-up period after the first radiosurgery (mean 39 months). Tumor regression was observed in 3 patients (43%). Three patients (43%) had improved clinically by the time of the follow-up examinations. No patient suffered from symptomatic radiation injury. CONCLUSION: Although we have treated only 7 patients using two-staged GKS, we believe this treatment may be a very useful option for large petroclival and cavernous sinus meningiomas in selected patients.  相似文献   
86.
Treatment for brain metastasis from lung cancer in the era of radiosurgery   总被引:1,自引:0,他引:1  
OBJECTIVE: The treatment for brain metastasis has undergone remarkable changes since the development of radiosurgery. We investigated the results of treatment for brain metastasis from lung cancer since the initiation of gamma knife radiosurgery (GKRS) and we discuss the usefulness of GKRS combined with other treatments in cases with recurrence. METHODS: We treated 142 patients with brain metastasis from lung cancer. Sixteen patients were treated surgically, 11 patients were treated with whole brain radiation therapy (WBRT), and 115 patients were treated with GKRS. Our treatment plan is to use GKRS in cases with less than 5 lesions and lesions less than 3 cm in mean diameter. We use WBRT in cases with 5 or more lesions, and surgery in cases with lesions 3 cm or larger. If new lesions or tumor regrowth appeared after the initial treatment, we retreated them with one of the methods mentioned above. RESULTS: Twice or three-time treatments were performed in 30 patients. Median survival including all cases was 10 months and the number of deaths due to local treatment failure was only 5 (6.5%) out of the total 77 deaths which occurred. CONCLUSION: We were able to carry out less invasive treatment for brain metastasis from lung cancer by utilizing GKRS. Though we have to consider the indications for other treatments, we can say that radiosurgery is usually the treatment of first choice for brain metastasis from lung cancer. When new lesions appear in cases where a particular initial treatment was used, it is possible to maintain or improve the quality of life by retreatment, using a combination of GKRS, surgery or WBRT, to prolong the patient's life.  相似文献   
87.
OBJECTIVE: The aim of this study was to determine the feasibility of using the ileal neobladder as a substitute for the urinary bladder following total pelvic exenteration for rectal carcinoma. PATIENTS AND METHODS: Between 1992 and 1998, we performed total pelvic exenteration with ileal neobladder in 5 men with rectal carcinoma. Four patients had primary tumors, and one had recurrent disease after low anterior resection for rectal carcinoma. Histological types were adenocarcinoma in 4 and squamous cell carcinoma in 1. Invaded organs were: the urinary bladder in 1, the urinary bladder and prostate in 2, the prostate and seminal vesicle in 1, and the prostate in 1. RESULTS: There was no operative death. In 1 patient, an ileal conduit was needed because of partial necrosis of the neobladder. Minor leakage on the dorsal wall of the neobladder occurred in 2 patients, which was successfully stopped with simple closure and a gluteus maximus fasciocutaneous flap, respectively. All except one patient with the ileal conduit could void via the urethra. Complete daytime urinary continence was achieved, but nocturnal continence was maintained with voiding once or twice per night. As the urodynamic state, the mean maximum flow rate was 20.9 ml/s (range 9.0-34.1), the mean average flow rate was 7.7 ml/s (range 3.0-11.0), and the mean voided volume was 285.5 ml (range 160-432). The mean length of follow-up was 47.8 months. One patient died of local recurrence 38 months postoperatively, and 1 died of pneumonia 10 months postoperatively. Both patients could void via the urethra until death. The other three patients are currently alive without any evidence of recurrence. CONCLUSIONS: Although total pelvic exenteration is a laborious surgical procedure, an ileal neobladder could be a good alternative to the urinary bladder enabling the patients to void via the urethra with urinary continence.  相似文献   
88.
BACKGROUND: We describe immunomodulatory effects of FK734, a humanized version of a mouse anti-human CD28 mAb (clone TN228), in vitro and in a chimeric human-mouse model of allograft rejection. METHODS: Cytokine production and proliferation were assessed in a mixed lymphocyte reaction containing FK734, human T cells, and endothelial cells or monocytes. FK734 was also administered to SCID mice engrafted with human skin and adoptively transferred with human peripheral blood mononuclear cells allogeneic to the skin graft. RESULTS: In vitro, FK734 enhanced secretion of interleukin-2 and interferon-gamma as well as proliferation of CD4+ and CD8+ T cells stimulated by allogeneic human leukocyte antigen (HLA)-DR+ human umbilical vein endothelial cells (which lack B7 molecules and FcgammaRs) or by blood monocytes (which express low levels of B7 molecules and FcgammaRs) compared with control mAb, but these effects were significantly smaller than those provided by mAb 28.2, a stimulatory mouse anti-human CD28 mAb, at comparable concentrations. However, FK734 generally inhibited cytokine secretion and T cell proliferation in cocultures with human umbilical vein endothelial cells transduced to express CD86. In vivo using SCID/beige mice bearing human skin with adoptively transferred peripheral blood mononuclear cells, administration of FK734 protected human endothelial cell-lined microvessels, significantly but incompletely reducing endothelial cell injury and T cell infiltration into the graft one or two weeks later. CONCLUSIONS: FK734 is a partial agonist of CD28 signaling that can reduce human T cell alloresponses in the presence of strong costimulation by B7 molecules in vitro and can reduce T cell-mediated skin allograft rejection in vivo.  相似文献   
89.
IgA nephropathy is the most common form of progressive glomerulonephritis although the pathophysiology of this nephropathy is unclear. The ddY mouse is a spontaneous animal model with variable incidence and extent of glomerular injury mimicking human IgA nephropathy. Here, we transplanted bone marrow cells from 20-week-old ddY mice with beginning or quiescent IgA nephropathy into irradiated similar ddY mice, C57Bl/6 (Th1 prone) mice, or BALB/c (Th2 prone) mice. Serum IgA/IgG complex and Th1/Th2 polarization of spleen cells was determined by enzyme-linked immunosorbent assay and confirmed by fluorescent cytometric analysis. The ddY mice with commencing IgA nephropathy demonstrated strong polarization toward Th1, while those with quiescent disease were Th2 polarized. Serum levels of IgA/IgG2a immune complex significantly correlated with the severity of the glomerular lesions. Bone marrow taken from mice with commencing IgA nephropathy conferred IgA nephropathy with Th1 polarization in recipient-quiescent mice, while transplantation from the quiescent mice ablated glomerular injury and mesangial IgA/IgG deposition in those commencing IgA disease. However, adoptive transfer of CD4(+) T cells from those whose disease began failed to induce any IgA deposition or renal injury. Our study suggests that bone marrow cells, presuming IgA producing cells, may initiate this disease. Th1 cells may be involved in the pathophysiology of the disease after glomerular IgA deposition.  相似文献   
90.
Calcium deposition in the skin, known as calcinosis cutis, is an uncommon disorder caused by an abnormal deposit of calcium phosphate in the skin. We report a case of idiopathic calcinosis cutis in fingertip treated with surgical excision followed by the occlusive dressing using aluminum foil, and obtained significant pain relief and round-shaped fingertip which looked normal.  相似文献   
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