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21.
Prabhudas S Patel Michelle L Varney Bhavana J Dave Rakesh K Singh 《Journal of interferon & cytokine research》2002,22(4):427-435
In the present study, we demonstrate that upregulation of interleukin-1beta(IL-1beta)-mediated and tumor necrosis factor-alpha (TNF-alpha)-mediated IL-8 expression in human malignant melanoma cells is modulated by the activation of nuclear factor-kappaB (NF-kappaB). Addition of capsaicin (8-methyl-N-vanillyl-6-nonenamide), a known inhibitor of NF-kappaB, resulted in the inhibition of constitutive as well as IL-1beta-induced and TNF-alpha-induced IL-8 expression in melanoma cells. The inhibition of IL-8 expression was dependent on the concentration of capsaicin and duration of treatment. Further, electrophoretic mobility shift assay (EMSA) of nuclear extracts from melanoma cells showed a constitutive activation of NF-kappaB and activated protein 1 (AP-1), which was upregulated following treatment with IL-1beta. Treatment of melanoma cells with capsaicin inhibited activation of constitutive and IL-1beta-induced NF-kappaB, but not AP-1, leading to inhibition of IL-8 expression. Further, downregulation of IL-8 expression in capsaicin-treated melanoma cells resulted in inhibition of in vitro cell proliferation. These results demonstrate that constitutive and induced NF-kappaB activation regulates IL-8 expression in melanoma cells. Downregulation of constitutive and induced NF-kappaB activation in malignant melanoma cells leads to inhibition of IL-8 production and in vitro cell proliferation. 相似文献
22.
Transport of molecules across tumor vasculature 总被引:16,自引:0,他引:16
Rakesh K. Jain 《Cancer metastasis reviews》1987,6(4):559-593
The vascular-extravascular exchange of fluid and solute molecules in a tissue is determined by three transport parameters (vascular permeability, P, hydraulic conductivity, Lp, and reflection coefficient, ); the surface area for exchange, A; and the transluminal concentration and pressure gradients. The transport parameters and the exchange area for a given molecule are governed by the structure of the vessel wall. In general, tumor vessels have wide interendothelial junctions; large number of fenestrae and transendothelial channels formed by vesicles; and discontinuous or absent basement membrane. While these factors favor movement of molecules across tumor vessels, high interstitial pressure and low microvascular pressure may retard extravasation of molecules and cells, especially in large tumors. These characteristics of the transvascular transport have significant implications in tumor growth, metastasis, detection and treatment. 相似文献
23.
Glioblastoma (GBM) is the most malignant brain tumor and accounts for most adult brain tumors. Current available treatment options for GBM are multimodal, which include surgical resection, radiation, and chemotherapy. Despite the significant advances in diagnostic and therapeutic approaches, GBM remains largely resistant to treatment, with a poor median survival rate between 12 and 18 months. With increasing drug resistance, the introduction of phytochemicals into current GBM treatment has become a potential strategy to combat GBM. Phytochemicals possess multifarious bioactivities with multitarget sites and comparatively marginal toxicity. Among them, curcumin is the most studied compound described as a potential anticancer agent due to its multi-targeted signaling/molecular pathways properties. Curcumin possesses the ability to modulate the core pathways involved in GBM cell proliferation, apoptosis, cell cycle arrest, autophagy, paraptosis, oxidative stress, and tumor cell motility. This review discusses curcumin’s anticancer mechanism through modulation of Rb, p53, MAPK, P13K/Akt, JAK/STAT, Shh, and NF-κB pathways, which are commonly involved and dysregulated in preclinical and clinical GBM models. In addition, limitation issues such as bioavailability, pharmacokinetics perspectives strategies, and clinical trials were discussed. 相似文献
24.
25.
The case is reported of a 37-year-old woman who complained of a gradually progressive mass in the left medial canthus area of one year's duration associated with epiphora. Although the clinical and investigative observations were suggestive of an acquired lacrimal sac cyst, the diagnosis was clinched by the operative and histopathological findings. Excision of the cyst along with dacryocystorhinostomy provided complete cure for this patient. 相似文献
26.
BACKGROUND AND OBJECTIVES: To note the effect on filtration function of using polyglactin sutures for scleral flap suturing in trabeculectomy. PATIENTS AND METHODS: Polyglactin sutures were compared with nylon sutures to secure the scleral flap of trabeculectomy in 30 consecutive eyes. Parameters studied were intraocular pressure, central anterior chamber depth, and bleb score in this randomized prospective study. RESULTS: Observations regarding intraocular pressure, central anterior chamber depth and bleb score in the early postoperative period were comparable in the 2 groups. The results at 12 months follow-up reveal a lower mean IOP (P < 0.05) and a higher mean bleb score (P < 0.05) in the group with polyglactin sutures. Success rate (defined as IOP < 21 mm Hg) at 12 months was 100% with use of polyglactin sutures compared to 80% with nylon sutures. CONCLUSIONS: Polyglactin sutures can be used as an alternative to nylon sutures for scleral flap suturing in trabeculectomy, with the possible additional benefit of better long-term filtration function. 相似文献
27.
Purpose
We determined if separation of spermatozoa (washed) on a discontinuous colloidal suspension of silica (Percoll†) density gradient before cryopreservation improves post-thaw motility compared to an unprocessed (raw) cryopreserved sample.Materials and Methods
Ten normal healthy volunteers recruited into the andrology laboratory donor program were studied. Raw and washed cryopreserved spermatozoa were compared for loss of motility with time, motion characteristics, viability and membrane integrity after incubation for 1, 6 and 24 hours. Within group comparisons were made to baseline measurements (0 hours before incubation).Results
Raw and washed cryopreserved spermatozoa showed statistically significant decreases in motility and other motion characteristics after thawing. There were significant decreases in motility and other motion characteristics after incubation periods of 1, 6 and 24 hours, and significant decreases in viability and membrane integrity at 6 and 24 hours in the unprocessed spermatozoa. Although, motility and motion characteristics of washed samples decreased significantly with longer incubation periods, loss of motility with time (longevity) was greater in raw samples. Washed samples retained greater sperm motility for up to 24 hours (p less than 0.03).Conclusions
Specimens prepared by Percoll separation techniques before freezing offer the possibility of selecting spermatozoa that retain motility for up to 24 hours. This finding can be of benefit for couples undergoing intrauterine insemination to achieve pregnancy. 相似文献28.
Jonas M. Weissbrod Rakesh K. Jain Francis M. Sirotnak 《Journal of pharmacokinetics and pharmacodynamics》1978,6(6):487-503
A lumped compartmental model has been derived to predict methotrexate concentration as a function of time for L1210 cells in BD2F
1
female mice at doses ranging from 3 mg/kg to 400 mg/kg. Using standard methods of parameter estimation as well as experimental determinations, an integrated approach was derived to account for the differences between the subcutaneous (s.c.) and intraperitoneal (i.p.) modes of injection. It was found that a single generalized forcing function can be used to fit plasma concentration after s.c. injection for all doses. Adequate fits (average error<20% while the standard deviation of experimental determinations was±22%) of L1210 cell data after s.c. injection were obtained. The best results were for a maximum facilitated influx constant Vmax
of 0.424 g/min/ml, a Michaelis influx constant Km
of 1,42 g/ml, and a first-order efflux constant of 0.047 min–1.The model simulations were not sensitive to Vmax, Km,and so long as the ratio Vmax/was approximately 9g/ml. The values of V
max
,K
m
,and which were obtained from our analysis of the in vivodata can be explained on the basis of previously performed in vitroexperiments. The parameters obtained from modeling the s.c. data were then applied for i.p. injection data. The resulting fits were adequate (average error<20% while the standard deviation of experimental determinations was±22%). A single generalized forcing function for drug concentration in the peritoneal cavity after i.p. injection for all doses was derived. The application of these results enables the prediction of methotrexate concentration in neoplastic cells at other doses after either s.c. or i.p. injection. 相似文献
29.
Dayananda S Sharma Rakesh Jalali Chandrashekhar M Tambe Deepak D AnimeshDeshpande 《Radiotherapy and oncology》2004,70(1):49-54
BACKGROUND AND PURPOSE: The aim of this work was to measure the dose to foetus both in vivo and in vitro during three-dimensional conformal radiation therapy (3DCRT) in a pregnant patient with a pituitary adenoma. The study was then extended to assess the components contributing to the foetal dose such as collimator scatter, internal scatter, head leakage, wedge scatter and multileaf collimator (MLC) effect. PATIENTS AND METHODS: A 30-year-old pregnant woman with a non-functioning pituitary macroadenoma was planned for 3DCRT with 6MV X-ray using four equally weighted MLC-shaped non-coplanar wedged portals. In vivo dosimetry was carried out using thermoluminescent (TL) phosphor powder, which was placed at different positions on the patient, corresponding to different locations in the uterus and also at external os. In vitro measurements were also performed on a simulated phantom using the same set-up parameters and beam arrangement to verify the in vivo measured dose. Experiments were carried out to measure the respective contributions of different components towards peripheral dose. RESULTS: In vitro measured dose to foetus was found to be slightly more than that of in vivo measurement with a maximum of 0.044% of the prescribed dose of 45Gy, which corresponded to 0.0199+/-0.0008Gy. Thermoluminescence dosimeter (TLD) kept at the external os of the patient showed a dose of 0.031% of the prescribed dose. Among the various components of the peripheral dose (foetal dose) measured, head leakage was found to be the leading cause contributing 52%, followed by wedge scatter (31%), collimator scatter (14%) and internal scatter (13%). The use of MLC reduced not only the volume of normal brain irradiation as compared to open fields but also the peripheral dose by 10%. CONCLUSION: Radiotherapy of brain tumours during pregnancy poses a unique clinical situation and decisions to deliver radiotherapy should be taken after detailed in vitro and in vivo dosimetric measurements. Our findings suggest that the beam arrangement using 3-4-fields generally used for 3DCRT of brain tumour with MLC for optimal coverage can be employed for pregnant patients even in early trimester. A possible increase in foetal dose from wedges to a large extent can be compensated with the use of MLC. 相似文献
30.
The p21-activated kinases signal through a number of cellular pathways fundamental to growth, differentiation and apoptosis.
A wealth of information has accumulated at an impressive pace in the recent past, both with regard to previously identified
targets for p21-activated kinases that regulate the actin cytoskeleton and cellular stress pathways and with regard to newly
identified targets and their role in cancer. Emerging data also provide new clues towards a previously unappreciated link
between these various cellular processes. The present review attempts to provide a quick tutorial to the reader about the
evolving significance of p21-activated kinases and small GTPases in breast cancer, using information from mouse models, tissue
culture studies, and human materials. 相似文献