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71.
72.
In previous in vitro studies, the authors showed that recombinant interleukin-2 (rIL-2) stimulated peripheral blood lymphocytes (PBL) from patients with malignant brain tumors to generate cells that were lytic for fresh autologous tumor but not for lymphocytes or lymphoblasts. We then tried the adoptive transfer of such lymphokine-activated killer-(LAK) cells induced from patients with meningeal gliomatosis (MG) and meningeal carcinomatosis (MC). PBL fractions were separated into a plastic bag by leukophoreses using HEMONETICS V 50. PBL were then harvested by LSM (Litton Bionetics, Kensington, Md.) gradient centrifugation according to the standard method. Human LAK cells were generated by placing 5 X 10(7) PBL in 10-cm diameter plastic dishes (Falcon) holding 20 ml of complete medium (CM) containing 100 units of rIL-2 (TGP-3, provided by TAKEDA Chemical Industries, Ltd.). The CM consisted of RPMI P640 with 0.1 mM nonessential amino acids, 1 microM sodium pyruvate, 5 X 10(-5) M 2-mercaptoethanol, 50 micrograms/ml of gentamicin sulfate, 0.03% glutamine and 2% heat-inactivated human AB serum. The dishes were incubated horizontally at 37 degrees C in a 5% CO2 atmosphere for 72-96 hours. The LAK cells were then harvested, washed three times with Hanks' balanced salt solution (HBSS) and resuspended in HBSS for transfer to patients. 1-2 X 10(8) LAK cells were injected intrathecally through Ommaya's reservoir or a V-P shunt reservoir twice a week. Portions of LAK cells were tested for cytotoxicity in vitro. During the adoptive transfer of LAK cells, patients were given intravenous injections of 500 units of rIL-2 every day. Case 1: A 29-year-old man with meningeal gliomatosis.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
73.
Reserpine was found to enhance the cytotoxicity of ACNU on ACNU-resistant C6 glioma (C6/ACNU) cells in vitro. When reserpine was added along with ACNU to the C6/ACNU cells in vitro. When reserpine was added along with ACNU to the C6/ACNU culture in vitro at a concentration of 10 microM, the IC50 of ACNU for C6/ACNU cells decreased to the level of that for C6 cells and ACNU resistance was completely overcome in vitro. Furthermore, intracellular uptake of ACNU increased in both sensitive (C6) and resistant (C6/ACNU) glioma cells when 20 microM reserpine was added to the culture medium. Reserpine (20 microM) enhanced the cellular level of ACNU in C6 cells 1.5-fold and enhanced the level of ACNU in C6/ACNU cells 4-fold. The amount of ACNU incorporated into C6/ACNU cells reached the same level as that incorporated into C6 cells. The enhanced cytotoxicity of ACNU in vitro could be explained by the effective intracellular accumulation of ACNU resulting from the increase of intracellular uptake of ACNU in C6/ACNU cells by reserpine.  相似文献   
74.
Background  The skin has evolved an epithelial defence mechanism which is characterized by antimicrobial peptides that inactivate various microorganisms and exhibit stimulatory activities bridging innate and adaptive immunity. Dermcidin (DCD) is a newly isolated antimicrobial peptide produced by the eccrine sweat glands in the skin. Recently, the DCD peptides DCD-1 and DCD-1L have been shown to display in vitro microbicidal activities against bacteria and viruses.
Objectives  Because some skin-derived antimicrobial peptides activate keratinocytes, we investigated whether DCD-1L would also trigger keratinocyte activation.
Methods  Normal human keratinocytes were used in this study. The ability of DCD-1L to induce the production of cytokines/chemokines by keratinocytes was determined by enzyme-linked immunosorbent assay, and various inhibitors were used to investigate the stimulatory mechanism of DCD-1L. Mitogen-activated protein kinase (MAPK) phosphorylation and NF-κB activation were analysed by Western blotting.
Results  DCD-1L stimulated keratinocytes to generate cytokines and chemokines including tumour necrosis factor-α, interleukin-8 (CXCL8), interferon-inducible protein 10 (CXCL10) and macrophage inflammatory protein-3α (CCL20). To determine the molecular mechanism involved, we showed that DCD-1L-mediated cytokine/chemokine production was controlled by both G-protein and MAPK pathways, as evidenced by the inhibitory effects of pertussis toxin and specific inhibitors for p38 and ERK, but not for JNK, on DCD-1L-induced keratinocyte activation. Furthermore, we confirmed that DCD-1L could induce phosphorylation of p38 and ERK, and noticeably upregulated NF-κB activation.
Conclusions  Taken together, the new activity of DCD-1L to stimulate the production of cytokines/chemokines by keratinocytes provides novel evidence for the implication of DCD, beyond its microbicidal ability, in skin immunity.  相似文献   
75.
Summary It has been suggested that peanut agglutinin (PNA)-binding sites in benign and malignant tissues were quite different. To clarify the difference of PNA-binding sites between benign and malignant ependymoma, PNA-binding sites are investigated on the surface membrane of tissues from benign and malignant ependymomas and cultured ependymoma cells. In four of five malignant ependymoma cases, PNA binding occurred in a diffuse cell membrane fashion or granular intracytoplasmic fashion without neuraminidase treatment. On the other hand, PNA binding was observed without neuraminidase treatment in only two of eight benign ependymoma cases. After neuraminidase treatment, all of our benign and malignant ependymoma cases evidenced PNA binding. PNA binding was clearly evident on the cell membrane of ependymoma cells which were able to express organotypic structures, that is, to form ependymal rosettes after neuraminidase treatment. Normal rat ependymal cells showed PNA binding only after neuraminidase treatment. These findings suggest that the masking of PNA-binding sites of ependymoma cells by sialic acid may be correlated with tumor cell differentiation.  相似文献   
76.
Solitary late recurrence is an unpredictable behavior pattern of renal cell carcinoma. We describe a patient with recurrence at the cranial bone 10 years after surgical management and another with recurrence at the sacral bone 13 years after treatment with radiotherapy and alpha-interferon. Both patients have been followed satisfactorily for 9 months. Unpredictable behavior of renal cell carcinoma makes lifelong followup of patients necessary. If a solitary recurrence is detected operative management definitely should be considered depending on the site of recurrence.  相似文献   
77.
The method for determining erythrocyte pyrimidine 5'-nucleotidase (P5N EC 3.1.3.5) activity has been simplified using an automated high performance liquid chromatograph (HPLC). The activity determined by the simplified method agreed closely with that obtained by conventional methods. In 161 lead workers P5N activity declined linearly with increasing blood lead concentrations (Pb-B) between 20 and 80 micrograms/100 g, and correlated well with Pb-B (r = -0.87). For the same group of workers, correlation coefficients between Pb-B v ALA-D activity, zinc protoporphyrin, ALA-U, and coproporphyrin were -0.87, 0.73, 0.70, and 0.32, respectively. At Pb-B greater than or equal to 40 micrograms/100 g, the validity of P5N (1.86 at a cut off of 10 less than or equal to units) was higher than that of other indicators examined. P5N activity was fairly stable during the storage of samples for two weeks at 4 degrees C. Determination of P5N activity by this method may be a useful indicator in screening for moderate exposure to lead.  相似文献   
78.
Intracranial cystic hemangiopericytoma--case report.   总被引:2,自引:0,他引:2  
A rare case of intracranial hemangiopericytoma associated with a large cyst was treated by gross total removal and local irradiation. The tumor has not recurred for 16 months, although the effectiveness of radiation therapy for hemangiopericytoma is unclear. Histological examination of the tumor specimen showed aggregation of the microcystic components, possibly contributing to the cyst formation. Hemangiopericytoma should not be classified as meningioma because of the different neoplastic and cytological properties. Complete surgical removal is essential for this tumor because of its malignancy.  相似文献   
79.
The cardiovascular effects of dobutamine (DOB) combined with methylprednisolone (MP) were studied during thoracic epidural analgesia (TEA) in 59 patients undergoing operations on upper abdomen. To establish TEA, 8-10 ml of lidocaine 20 mg.ml-1 was injected into the epidural space through the T8-T9 interspace. The patients was intubated after fentanyl 0.2 mg, thiopental 3 mg.kg-1 and vecuronium 0.2 mg.kg-1. Anesthesia was maintained with 67% N2O, 33% O2 and 0.6% enflurane and DOB was infused at a rate of 5 micrograms.kg-1.min-1 during the surgical operation. Systolic blood pressure and urinary output after TEA did not decrease in the two groups, pretreated with MP 5 mg.kg-1 one hour or immediately before TEA, but decreased in the control group without MP injection. Heart rate showed no significant changes after TEA in all groups. We conclude that MP may potentiate the cardiovascular effects of DOB during TEA.  相似文献   
80.
In the previous reports, we demonstrated that intracisternal ACNU is effective in prolonging the survival time of rats with meningeal carcinomatosis induced by intracisternal inoculation of Walker 256 carcinosarcoma cells, and systemic and local toxicity can be avoided by adjusting the drug dose. In this experiment, we studied distribution of 14C-ACNU in the rat brain after intracisternal administration using a macroscopical autoradiographic method. One muCi of ethylene-14C-ACNU was percutaneously injected into the cisterna magna of normal female Wistar rats weighing approximately 150 g. The animals were sacrificed 5 and 30 minutes, and 3 hours after injection (3 animals in each group). The brain was quickly removed and frozen in Freon. 14C-ACNU autoradiograms were made in coronal sections of the brain, which were cut in 20 mu thick and exposed to the film for 7 days. In 5 minutes after administration, high radioactivity was distributed in the subarachnoid space of the basal and ambient cisterns and hypocampal fissures, and subpial brain tissue up to 1 or 2 mm in depth. High radioactivity was also present in the ventricles and subependymal layer. In 30 minutes after administration, total radioactivity has already reduced in amount, however, local distribution has not changed so much as compared to that of 5 minutes after injection. No radioactivity was observed in the deeper part of the brain. In 3 hours after administration, only a small amount of radioactivity remained in the subarachnoid space and subpial region.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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