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1.
Pancreatic metastasis of malignant melanoma is rarely diagnosed while the patient is alive. We report a case of metastatic melanoma of the pancreas in a 35-year-old woman presenting with a solid mass of the pancreas. Her past medical history included a radical hysterectomy 2 years previously for malignant melanoma of the vagina. Twelve months later, lung metastasis was also resected. EUS-guided fine needle aspiration (EUS-FNA) identified that the pancreatic tumor was histologically and immunohistochemically identical to the surgical specimen of her lung neoplasm. Imaging studies including US, CT, and MRI have limited value to distinguish the tumors from primary ductal adenocarcinoma. EUS-FNA can provide tissue diagnosis from pancreatic masses, specifically when other modalities have failed.  相似文献   
2.
Abstract: Suitable evaluation systems are critical for ranking various biomaterials in order to develop a method to design and synthesize nonthrombogenic biomaterials. We have recently developed an in vitro test system to evaluate platelet/biomaterial interactions in whole blood. The system consists of a parallel plate flow cell and epifluorescent video microscopy (EVM). A glass coverslip coated with a polymer was incorporated into the flow cell, and blood was perfused using a syringe pump via a polymer–coated PVC tubing connected to the flow cell. Whole human blood was anticoagulated with heparin (2 U/ml), and the platelets were labeled with the fluorescent dye mepacrine (5 μM). This system permitted real–time and dynamic observations of platelet/biomaterial interactions in whole blood under a defined flow condition. In order to evaluate the feasibility of this system, two different segmented polyether–polyurethanes (SPEUs), PU–PTMG(650) and PU–PTMG(2000), were chosen as test polymers. Surface characteristics verified with electron spectroscopy for chemical analysis (ESCA) and contact angle measurements showed similar results in both SPEUs. Blood was perfused at a wall shear rate of 200 s–1 for 20 min. Excitation light was applied for 2 s at 1 min intervals. The real–time image was then analyzed at each time point for the percentage of surface area of platelet coverage. Plasma β–thromboglobulin (β–TG) levels were also measured before and after each run. PU–PTMG(650) showed a significantly higher number of adhered platelets than PU–PTMG(2000) at each time point. β–TG levels of PU–PTMG(650) were also higher than those of PU–PTMG(2000), which is comparable to the results of EVM. Thus, this EVM system has been proven to be an excellent and highly sensitive in vitro analytical method for evaluating platelet/biomaterial interactions.  相似文献   
3.
A 42-year-old woman with progressive myelopathy and mononeuritis multiplex is reported. The neurological examination on admission revealed hyperreflexia of the four extremities with pathological reflexes and moderate muscle weakness of the lower extremities with spasticity. Sensory disturbance was distributed on the areas of the bilateral lateral cutaneous femoral, the superficial peroneal and sural nerves. The antibody to HTLV-I in the serum and cerebrospinal fluid was more than 8192X and 512X, respectively. No sensory potential was recorded in the sensory conduction study of bilateral lateral femoral cutaneous nerves. Corticosteroid therapy caused a marked improvement of the sensory and urinary disturbances and had a slight effect on the spastic gait. Our nerve conduction study found small sensory potentials with normal conduction velocities in the bilateral lateral femoral cutaneous nerves. These results suggested the presence of an axonal degeneration in the peripheral nerves in this case. There have been no reports in the literature regarding a case of HAM with mononeuritis multiplex.  相似文献   
4.
Background The antitumor effects of adoptive immunotherapy in combination with chemoradiotherapy were investigated in patients with oral squamous cell carcinoma. Methods Inductive chemoradiotherapy with peplomycin, 5-fluorouracil and60Co was given to 56 patients [CRI(−)group]. A local injection of adoptive lymphokine-activated killer (LAK) cells (≈2×108 cells) and small doses of interleukin-2(≈3×105 U) and interferon-gamma (≈2×105U) was given to 40 other patients in combination with the chemoradiotherapy [CRI(+) group]. Results Clinically, CR, PR, and LR were observed in 15 (37.5%), 24 (60.0%), and 1 (2.5%) of the patients in the CRI (+) group, respectively; and in 14 (25.0%), 38 (67.9%), and 4 of the patients (7.1%) in the CRI (−) group. The histopathological effects were correlated with the tumor remission rate, with lethal degeneration (grades III and IV), and prominent degeneration (grade IIB) in the tumor cells noted in 20 (50.0%) and 16 (40.0%) of the CRI(+) patients, respectively; and in 21 (37.5%) and 29 (51.8%) of the CRI (−) patients. Immunohistochemically, a prominent decrease of proliferating cell nuclear antigenpositive cells with a reciprocal increase of LeY-positve cells was induced by the chemoradioimmunotherapy. DNA fragmentation was observed in the mutant type p53-negative tumors in the CRI(+) group. Conclusion Adoptive immunotherapy with LAK cells and cytokines in combination with chemoradiotherapy induces advantageous anticancer effects resulting from necrosis and apoptosis.  相似文献   
5.
AIMS: p27 is a prominent regulator of cell proliferation by universally inhibiting the cell cycle, while Jun activation domain-binding protein 1 (Jab1), a multifunctional cell signaling protein, contributes to carcinoma progression by degrading p27. In this study, we investigated the expression of these proteins in medullary thyroid carcinoma. METHODS: We immunohistochemically examined Jab1 and p27 expression in 64 medullary thyroid carcinomas. RESULTS: Of the 64 cases examined, decreased p27 expression was observed in 38 cases (59.4%). The p27 expression level was inversely linked to tumour size as well as plasma calcitonin level. Jab1 expression level was generally high, and 46 cases (71.9%) were classified as overexpressing Jab1. The incidence was higher than those in papillary and follicular carcinomas, which were previously reported. Jab1 expression level was inversely linked to that of p27, and all five cases with only cytoplasmic but not nuclear staining of p27 overexpressed Jab1. CONCLUSIONS: These findings suggest that (1) decrease in p27 expression may contribute to local tumour growth; (2) Jab1 expression is related to the progression of medullary carcinoma by decreasing the amount of p27 in the cell and accelerating its degradation; and (3) Jab1 may play a more vital role in the pathogenesis of medullary carcinoma than papillary and follicular carcinomas.  相似文献   
6.
By Western blot analysis, the expression level of aquaporin (AQP) 5 in the submandibular gland (SMG) was found to be different among individual rats of the Sprague-Dawley (SD) strain. Such differences were observed for AQP5 but not for AQP1 and consequently the SD strain was divided into two groups, one expressing a high level of AQP5 and the other a low one. The difference in average intensity of expression between the two groups was more than twofold. Immunohistochemical analysis of the SMG demonstrated that the AQP5 protein was localized in the basal and apical/lateral plasma membrane of acinar cells in rats expressing the high level of AQP5. In the rat expressing the low level, however, this channel protein was localized strongly in the apical/lateral plasma membrane, but only very weakly in the basal membrane of the acinar cells. Such a diverse localization of AQP5 was confirmed by Western blotting as well. Breeding between brother and sister was repeated for two times within high expressers and low expressers to obtain the third generation progenies (F2); the AQP5 level of the SMG in the third generation (F2 rats) from high expressers was significantly higher than the F2 from low expressers. Our present study suggests the existence of genetic variation in the expression of a water channel protein, AQP5, in rats.  相似文献   
7.
To establish a novel strategy for the control of fungal infection, we examined the antifungal and neutrophil-activating activities of antimicrobial peptides. The duration of survival of 50% of mice injected with a lethal dose of Candida albicans (5 × 108 cells) or Aspergillus fumigatus (1 × 108 cells) was prolonged 3 to 5 days by the injection of 10 μg of peptide 2 (a lactoferrin peptide) and 10 μg of α-defensin 1 for five consecutive days and was prolonged 5 to 13 days by the injection of 0.1 μg of granulocyte-monocyte colony-stimulating factor (GM-CSF) and 0.5 μg of amphotericin B. When mice received a combined injection of peptide 2 (10 μg/day) with amphotericin B (0.5 μg/day) for 5 days after the lethal fungal inoculation, their survival was greatly prolonged and some mice continued to live for more than 5 weeks, although the effective doses of peptide 2 for 50 and 100% suppression of Candida or Aspergillus colony formation were about one-third and one-half those of amphotericin B, respectively. In vitro, peptide 2 as well as GM-CSF increased the Candida and Aspergillus killing activities of neutrophils, but peptides such as α-defensin 1, β-defensin 2, and histatin 5 did not upregulate the killing activity. GM-CSF together with peptide 2 but not other peptides enhanced the production of superoxide (O2) by neutrophils. The upregulation by peptide 2 was confirmed by the activation of the O2-generating pathway, i.e., activation of large-molecule guanine binding protein, phosphatidyl-inositol 3-kinase, protein kinase C, and p47phox as well as p67phox. In conclusion, different from natural antimicrobial peptides, peptide 2 has a potent neutrophil-activating effect which could be advantageous for its clinical use in combination with antifungal drugs.  相似文献   
8.
gamma/delta T cells are likely to participate in the immune response to tuberculous infection in humans. In this study, we carried out an investigation to characterize the responsiveness of gamma/delta T cells from tuberculous patients and healthy individuals to mycobacterial stimulation in vitro. Healthy subjects were assigned to the following two groups: those who had been exposed to tuberculosis (contacts) and those who had not been exposed (noncontacts). The percent gamma/delta T cells in fresh peripheral blood obtained from health care workers who were tuberculin skin test positive and who had constant contact with patients with active tuberculosis (healthy contacts) was significantly higher, whereas healthy noncontacts showed the normal range of gamma/delta T cells. Patients with active pulmonary tuberculosis also had low levels of gamma/delta T cells. HLA-DR antigen-bearing activated gamma/delta T cells were observed in higher percentages among healthy contacts than among healthy noncontacts or patients with pulmonary tuberculosis. In healthy contacts, gamma/delta T cells increased as a percentage of peripheral blood mononuclear cells after in vitro stimulation with purified protein derivative (PPD) tuberculin compared with the percentage of fresh peripheral blood mononuclear cells that they made up, whereas no such increase was observed in patients with tuberculosis or in healthy noncontacts. Phenotypic analysis of the gamma/delta T cells in healthy contacts, which increased in number in vitro in response to PPD, revealed the preferential outgrowth of CD4+ V gamma 2+ gamma/delta T cells. This expansion of gamma/delta T cells by PPD required accessory cells, and it was inhibited by the addition of an antibody against HLA-DR in culture. Proteolytic digestion of PPD showed that gamma/delta T cells increased in number in response to peptide, but not nonpeptide, components of PPD. These findings suggest that gamma/delta T cells, especially CD4+ V gamma 2+ gamma/delta T cells, may participate in the immune surveillance of tuberculous infections in humans.  相似文献   
9.
A 66-year-old male with osteoclast-like giant cell tumor of the liver that arose in the non-cirrhotlc liver is presented. The liver tests were almost normal, and plasma levels of alpha-fetoprotein and carcinoembryonic antigen were within normal limits. The findings of liver scan by 99mTc phytate, celiac angiography, and CT scans are described for the first time for this rare neoplasm, showing a large, unresectable liver tumor. Histologically, the tumor mainly consisted of osteoclast-like giant cells and mononuclear cells, which were focally arranged in a vaguely trabecular pattern and sarcomatous pattern. By an electromicroscopic study, however, no definitive evidence was obtained whether it arose from epithelial cells or nonepithellal cells. Various clinicopathological features were described and compared with previously reported cases including two cases arising in the liver.  相似文献   
10.
AIMS: Galectin-3, a member of the beta-galactoside binding family of lectins, has been regarded as a useful tool for discriminating malignant tumours from benign nodules of the thyroid, including the distinction between follicular carcinoma and adenoma. However, there are follicular tumours with unclear vascular or capsular invasion, which makes diagnosis more difficult. In this study, we investigated the relationship between galectin-3 expression and the degree of vascular or capsular invasion of follicular tumours. METHODS: We immunohistochemically investigated galectin-3 expression in 260 cases of follicular tumour with various degrees of vascular or capsular invasion classified into four categories. RESULTS: The galectin-3 expression level significantly increased with the degree of vascular or capsular invasion (p<0.0001). However, its diagnostic value for follicular carcinoma was not high because the sensitivity and specificity were 68.7% and 57.5%, respectively. CONCLUSIONS: Our findings suggest that galectin-3 plays a role in the transformation of follicular tumours from benign to malignant; however, when diagnosing follicular tumours, the presence of this protein should not be required for diagnosing malignant transformation in all cases. Therefore, we must conclude that galectin-3 should only be considered an adjuvant marker for follicular carcinoma.  相似文献   
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