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101.
102.
Silymarin protects dopaminergic neurons against lipopolysaccharide-induced neurotoxicity by inhibiting microglia activation 总被引:10,自引:0,他引:10
Wang MJ Lin WW Chen HL Chang YH Ou HC Kuo JS Hong JS Jeng KC 《The European journal of neuroscience》2002,16(11):2103-2112
An inflammatory response in the central nervous system mediated by activation of microglia is a key event in the early stages of the development of neurodegenerative diseases. Silymarin is a polyphenolic flavanoid derived from milk thistle that has anti-inflammatory, cytoprotective and anticarcinogenic effects. In this study, we first investigated the neuroprotective effect of silymarin against lipopolysaccharide (LPS)-induced neurotoxicity in mesencephalic mixed neuron-glia cultures. The results showed that silymarin significantly inhibited the LPS-induced activation of microglia and the production of inflammatory mediators, such as tumour necrosis factor-alpha and nitric oxide (NO), and reduced the damage to dopaminergic neurons. Therefore, the inhibitory mechanisms of silymarin on microglia activation were studied further. The production of inducible nitric oxide synthase (iNOS) was studied in LPS-stimulated BV-2 cells as a model of microglia activation. Silymarin significantly reduced the LPS-induced nitrite, iNOS mRNA and protein levels in a dose-dependent manner. Moreover, LPS could induce the activation of p38 mitogen-activated protein kinase (MAPK) and c-jun N-terminal kinase but not extracellular signal-regulated kinase. The LPS-induced production of NO was inhibited by the selective p38 MAPK inhibitor SB203580. These results indicated that the p38 MAPK signalling pathway was involved in the LPS-induced NO production. However, the activation of p38 MAPK was not inhibited by silymarin. Nevertheless, silymarin could effectively reduce LPS-induced superoxide generation and nuclear factor kappaB (NF-kappaB) activation. It suggests that the inhibitory effect of silymarin on microglia activation is mediated through the inhibition of NF-kappaB activation. 相似文献
103.
Chromosome 8p21-22 is a frequent site of loss of heterozygosity in many types of cancer, including hepatocellular carcinoma (HCC). Tumor necrosis factor-related apoptosis-inducing ligand-receptor 2 (TRAIL-R2/DR5), a member of tumor necrosis factor receptor family, is mapped to chromosome 8p21-22. Mutations of TRAIL-R2 have been detected in lung cancer, breast cancer, head and neck cancer, and non-Hodgkin's lymphoma. In this study, we analyzed the entire coding regions and all splicing sites of TRAIL-R2 in 40 HCCs and the death domain region in additional 60 HCCs. We could detect one point mutation in the death domain in only one HCC (1%). Our data suggest that somatic mutations of TRAIL-R2 gene do not play an important role in the carcinogenesis of HCC. 相似文献
104.
Carotid and transcranial color-coded duplex sonography in different types of carotid-cavernous fistula 总被引:5,自引:0,他引:5
Chen YW Jeng JS Liu HM Hwang BS Lin WH Yip PK 《Stroke; a journal of cerebral circulation》2000,31(3):701-706
BACKGROUND AND PURPOSE: Patients with carotid-cavernous fistula (CCF) may undergo direct or indirect shunting. Ultrasonography has value that is complementary to angiography in the assessment and follow-up of these patients. The aim of this study was to characterize findings provided by carotid duplex sonography (CDS) and transcranial color-coded duplex sonography (TCCD) in patients with different types of CCF. METHODS: CDS and TCCD were independently performed by technologists and neurologists. Digital subtraction or MR angiography was interpreted by a neuroradiologist. Ultrasonographic studies were categorized into 4 types: I, direct shunting only; II, direct shunting with a carotid aneurysm; III, indirect shunting only; and IV, mixed (direct and indirect) shunting. In addition to carotid and intracranial flow velocities, volume, and pulsatility, other direct and indirect ultrasound signs of shunting were evaluated. The direct sign of CCF was a mosaic flash detected by TCCD. Alteration of hemodynamic parameters on CDS and demonstration of draining veins with the use of TCCD were considered indirect signs. RESULTS: Fifteen patients (8 men, 7 women) were included in the study. According to angiographic results, patients in ultrasonographic classification types I (n=7) and II (n=3) corresponded to type A of Barrow's classification. Patients with type III (n=8) were Barrow's type C. Type IV (n=1) had a combination of Barrow's types A and C. On ultrasound, both direct and indirect signs were seen in types I, II, and IV CCF. The presence of a 2-colored oval mass divided by a zone of separation without turbulence differentiated type I from type II CCF. All patients with type III CCF had indirect signs, and only 1 patient had direct signs on TCCD. Abnormal TCCD findings were most commonly seen through the transorbital window (100%), followed by the transtemporal window (63%) and transforaminal window (40%). CONCLUSIONS: If only indirect ultrasonographic signs of CCF are present, TCCD can be used to predict an indirect CCF type on the basis of the origin of the fistula. With direct communication between carotid artery and cavernous sinus, both direct and indirect ultrasonographic signs can be found. The combination of CDS/TCCD may provide a noninvasive and reliable way to classify patients with CCF. 相似文献
105.
106.
Jeng C Michelson J Mizel M 《Foot & ankle international / American Orthopaedic Foot and Ankle Society [and] Swiss Foot and Ankle Society》2000,21(6):501-504
HYPOTHESES/PURPOSE: Although several studies in the literature have evaluated the abnormal sensory thresholds of diabetic feet to Semmes-Weinstein monofilament testing, there is very limited data on the sensory thresholds of individuals without diabetes or peripheral neuropathy. The purpose of this study was to assess the dorsal and plantar sensation of the feet from 40 healthy, college-aged volunteers using Semmes-Weinstein monofilaments. CONCLUSIONS/SIGNIFICANCE: Semmes-Weinstein testing is a useful tool in predicting which diabetic patients may be at risk for ulceration of the feet. Several studies have determined 5.07 to be the threshold for protective sensation. Based on the normal values derived in this study, the inability to feel a Semmes-Weinstein monofilament of 5.07 (as in diabetic neuropathy) represents a sensory threshold that is more than 50 times greater than normal. This means that roughly 98% of the sensory ability has been lost. METHODS: 20 male and 20 female volunteers between the ages of 18 to 22 years old were selected. None had a history of any significant injury or previous surgery to the foot or ankle. There were no known medical conditions associated with decreased foot sensation, (e.g.- diabetes, syphilis, leprosy, myelomeningocele, syringomyelia, or hereditary neuropathy). Volunteers were also questioned regarding participation in athletic activities. The subjects were blindfolded with the leg resting comfortably on a chair as 14 plantar and 5 dorsal locations were tested on each foot. The right foot was always tested first. Each site on the foot had the Semmes-Weinstein monofilaments applied to it first, in an order of increasing stiffness, then repeated in decreasing order, using all twenty monofilaments in the set. A positive threshold response was recorded when the subject could feel the filament and could accurately locate where on the foot the stimulus had been applied. The left foot was then tested in an identical fashion. RESULTS: The mean sensitivity for all sites was 3.63 (0.0075 SEM). There were significant differences between sites, between using increasing or decreasing monofilament stiffness, between subjects, and in some instances, between right foot and left foot values. When testing was performed from the higher to lower monofilament stiffness, subjects were found to have significantly better sensitivity, which indicates the importance of a consistent testing protocol (either all up or all down). Sensation in the lesser toes and the arch were the most sensitive followed by the hallux and the plantar metatarsal heads. The least sensitive site was the heel, with 1/6th the sensitivity of the most sensitive toes. 相似文献
107.
J. F. Tsai J. E. Jeng L. Y. Chuang M. L. Yang M. S. Ho W. Y. Chang M. Y. Hsieh Z. Y. Lin J. H. Tsai 《British journal of cancer》1997,75(10):1460-1466
To evaluate the diagnostic application of urinary transforming growth factor-beta1 (TGF-beta1) and serum alpha-fetoprotein (AFP) levels in hepatocellular carcinoma (HCC), TGF-beta1 and AFP were determined in 94 patients with cirrhotic HCC and in 94 sex- and age-matched patients with cirrhosis alone. TGF-beta1 and AFP levels in HCC were higher than in cirrhosis alone (P = 0.0001). There is an inverse correlation between TGF-beta1 and log AFP (r = -0.292, P = 0.004). Multivariate analysis indicated that TGF-beta1 and AFP were closely associated, in a dose-related fashion, with the development of HCC. Receiver-operating characteristic (ROC) curves were used to determine the optimal cut-off values of TGF-beta1 (50 microg g(-1) creatinine) and AFP (100 ng ml(-1)). Both TGF-beta1 and AFP showed a high specificity (99%) and positive likelihood ratio. The sensitivity was 53.1% for TGF-beta1 and 55.3% for AFP. The determination of both markers in parallel significantly increased the diagnostic accuracy (90.1%) and sensitivity (84%), with a high specificity (98%) and positive likelihood ratio (40.0). In conclusion, TGF-beta1 and AFP are independent tumour markers of HCC and may be used as complementary tumour markers to discriminate HCC from cirrhosis. 相似文献
108.
Women with estrogen receptor (ER) positive breast cancers frequently respond initially to inhibition of estrogen action but later relapse with re-growth of tumor. Previously, we have utilized MCF-7 human breast cancer cells deprived of estradiol long term (LTED cells) as the model system to study the regrowth phenomenon and have demonstrated that these cells exhibited increased cell proliferation rate and increased ER functionality during the adaptive processes. In this report, we examined the hypothesis that the mitogen-activated protein kinase (MAP kinase) signal was involved. We found that activated MAP kinase was elevated in LTED cells and that the MAP kinase specific inhibitor PD98059 was able to inhibit the elevated MAP kinase and [3H]thymidine uptake in LTED cells, suggesting mediation of DNA synthesis and proliferation by the MAP kinase pathway. Other MAP kinase upstream inhibitors, including genestein, RG13022, and mevastatin were also able to inhibit the [3H]thymidine uptake in LTED cells. Interestingly, the antiestrogen, ICI 182,780 was able to block the activated MAP kinase in LTED cells. Treatment with PD98059 did not block elevated basal ERE-CAT activity while at the same time inhibiting [3H]thymidine uptake in LTED cells. Furthermore, treatment with PD98059 partially blocked the E2-stimulated ERE-CAT activity and [3H]thymidine uptake in both LTED and in wild type cells, indicating that both MAP kinase-dependent and MAP kinase-independent pathways are involved in the transactivation function of ER. Taken together, our data suggest that the MAP kinase pathway is, in part, involved in the adaptive process which results in enhanced DNA synthesis and cell proliferation in the absence of exogenous estrogen in LTED 3ptcells. 相似文献
109.
110.
BACKGROUND: The purpose of the present study was to investigate the feasibility of teleconsultation with the mobile camera-phone to transfer clinical images and communicate on line for evaluation of replantation potential in completely amputated fingers. METHODS: Teleconsultations including clinical images of the amputated portion and stump as well as patient information were transmitted between the physicians in the emergency room and the consultant phlstic surgeon through Panasonic camera-phones, which had a built-in 110,000-pixel digital camera and a 65,536 colors display. The digital images displayed on the screen were further evaluated by three remote plastic surgeons individually and the evaluations were compared with the decision made according to onsite inspection by the consultant surgeon. RESULTS: The study population consisted of 35 patients with a total of 60 digital injures occurring between January to October 2003. The ability to identify the amputation location and status of amputation kwel from remote diagnosis was demonstrated by all three surgeons in 90% and 87% of these sixty amputated digits respectively. Of the 42 digits that were considered to have replantation potential during onsite evaluation, 38 (90%) digits were considered to be so by all three surgeons in group agreement during remote diagnosis. Of the 18 digits that were not considered to be replantable during onsite evaluation, 15 (83%) digits were also deemed without replantation potential, thus making the sensitivity and specificity of recognizing digital replantation potential, 90% and 83_'O re,_1pectively. CONCLUSIONS: The camera-phone is a feasible tool for remote evaluation regarding the replantation potential of completely amputated fingers and it holds significant promise in avoiding unnecessary patient transfer by providing useful information. 相似文献