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21.

Background

Nasopharyngeal carcinoma (NPC) is known for its high metastatic potential and locoregional recurrence, although the molecular alterations that are driving NPC metastasis remain unclear at this time. This study aimed to examine the expression of fibulin-5 in NPC, correlate the results with clinicopathological variables and survival, and to investigate the role of fibulin-5 in human NPC cell lines.

Material and Methods

Standard semi-quantitative-RT-PCR, quantitative-RT-PCR, immunoblotting, and immunohistochemistry were used to investigate the mRNA and protein expression profiles of fibulin-5 in normal and NPC tissues. Immunohistochemistry of fibulin-5 was correlated with clinicopathological characteristics by univariate analyses. NPC cells overexpressing fibulin-5 or fibulin-5-siRNA cells were generated by stable transfection to characterize the molecular mechanisms of fibulin-5-elicited cell growth and metastasis.

Results

Our results demonstrated that fibulin-5 overexpression in NPC specimens and significantly correlated with advanced tumor metastasis indicating a poor 5-year overall survival. Fibulin-5 was mainly expressed in the nucleus in human NPC specimens and cell lines. Functionally, fibulin-5 overexpression yielded fast growth in NPC cells. In addition, fibulin-5 promotes cell metastasis in NPC cells through increased FLJ10540 and phosphor-AKT activity. In contrast, siRNA depletion of fibulin-5 suppressed FLJ10540 expression and phosphor-AKT activity. Suppression of either fibulin-5 or FLJ10540 can cause significant inhibition with regards to cell motility in NPC cells. Finally, immunohistochemical analysis of human aggressive NPC specimens showed a significant and positive correlation between fibulin-5 and FLJ10540 expression.

Conclusion

Higher fibulin-5 expression is not only an important indicator of poor survival, but also contributes to the development of new therapeutic strategies in the FLJ10540/AKT pathway for NPC treatment.  相似文献   
22.
Plasmodiophora brassicae causes clubroot disease in cruciferous plants, and is an emerging threat to Canadian canola (Brassica napus) production. This review focuses on recent studies into the pathogenic diversity of P. brassicae populations, mechanisms of pathogenesis and resistance, and the development of diagnostic tests for pathogen detection and quantification. TAXONOMY: Plasmodiophora brassicae is a soil-borne, obligate parasite within the class Phytomyxea (plasmodiophorids) of the protist supergroup Rhizaria. DISEASE SYMPTOMS: Clubroot development is characterized by the formation of club-shaped galls on the roots of affected plants. Above-ground symptoms include wilting, stunting, yellowing and premature senescence. DISEASE CYCLE: Plasmodiophora brassicae first infects the root hairs, producing motile zoospores that invade the cortical tissue. Secondary plasmodia form within the root cortex and, by triggering the expression of genes involved in the production of auxins, cytokinins and other plant growth regulators, divert a substantial proportion of plant resources into hypertrophic growth of the root tissues, resulting in the formation of galls. The secondary plasmodia are cleaved into millions of resting spores and the root galls quickly disintegrate, releasing long-lived resting spores into the soil. A serine protease, PRO1, has been shown to trigger resting spore germination. PHYSIOLOGICAL SPECIALIZATION: Physiological specialization occurs in populations of P. brassicae, and various host differential sets, consisting of different collections of Brassica genotypes, are used to distinguish among pathotypes of the parasite. DETECTION AND QUANTIFICATION: As P. brassicae cannot be cultured, bioassays with bait plants were traditionally used to detect the pathogen in the soil. More recent innovations for the detection and quantification of P. brassicae include the use of antibodies, quantitative polymerase chain reaction (qPCR) and qPCR in conjunction with signature fatty acid analysis, all of which are more sensitive than bioassays. RESISTANCE IN CANOLA: Clubroot-resistant canola hybrids, recently introduced into the Canadian market, represent an important new tool for clubroot management in this crop. Genetic resistance must be carefully managed, however, as it has been quickly overcome in other regions. At least three resistance genes and one or two quantitative trait loci are involved in conferring resistance to P. brassicae. Root hair infection still occurs in resistant cultivars, but secondary plasmodia often remain immature and unable to produce resting spores. Fewer cell wall breakages occur in resistant hosts, and spread of the plasmodium through cortical tissue is restricted. More information on the genetics of clubroot resistance in canola is needed to ensure more effective resistance stewardship. USEFUL WEBSITES: http://www.canolacouncil.org/clubroot/resources.aspx, http://tu-dresden.de/die_tu_dresden/fakultaeten/fakultaet_mathematik_und_naturwissenschaften/fachrichtung_biologie/botanik/pflanzenphysiologie/clubroot, http://www.ohio.edu/people/braselto/plasmos/  相似文献   
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The antioxidative property of green tea against iron-induced oxidative stress was investigated in the rat brain both in vivo and in vivo. Incubation of brain homogenates at 37 degrees C for 4 hours in vitro increased the formation of Schiff base fluorescent products of malonaldehyde, an indicator of lipid peroxidation. Auto-oxidation (without exogenous iron) of brain homogenates was inhibited by green tea extract in a concentration-dependent manner. Moreover, incubation with iron (1 microM) elevated lipid peroxidation of brain homogenates after 4-hour incubation at 37 degrees C. Co-incubation with green tea extract dose-dependently inhibited the iron-induced elevation in lipid peroxidation. For the in vivo studies: ferrous citrate (iron, 4.2 nmoles) was infused intranigrally and induced degeneration of the nigrostriatal dopaminergic system of rat brain. An increase in lipid peroxidation in substantia nigra as well as a decrease in dopamine content in striatum was observed seven days after the iron infusion. Intranigral infusion of green tea extract alone did not increase, and in some cases, even decreased lipid peroxidation in substantia nigra. Co-infusion of green tea extract prevented oxidative injury induced by iron. Both iron-induced elevation in lipid peroxidation in substantia nigra and iron-induced decrease in dopamine content in striatum were suppressed. Oral administration of green tea extract for two weeks did not prevent the iron-induced oxidative injury in nigrostriatal dopaminergic system. Our results suggest that intranigral infusion of green tea extract appears to be nontoxic to the nigrostriatal dopaminergic system. Furthermore, the potent antioxidative action of green tea extract protects the nigrostriatal dopaminergic system from the iron-induced oxidative injury.  相似文献   
26.
In the present study, we screened proteomic and cytokine biomarkers between patients with adenomatous polyps and colorectal cancer (CRC) in order to improve our understanding of the molecular mechanisms behind turmorigenesis and tumor progression in CRC. To this end, we performed comparative proteomic analysis of plasma proteins using a combination of 2DE and MS as well as profiled differentially regulated cytokines and chemokines by multiplex bead analysis. Proteomic analysis identified 11 upregulated and 13 downregulated plasma proteins showing significantly different regulation patterns with diagnostic potential for predicting progression from adenoma to carcinoma. Some of these proteins have not previously been implicated in CRC, including upregulated leucine‐rich α‐2‐glycoprotein, hemoglobin subunit β, Ig α‐2 chain C region, and complement factor B as well as downregulated afamin, zinc‐α‐2‐glycoprotein, vitronectin, and α‐1‐antichymotrypsin. In addition, plasma levels of three cytokines/chemokines, including interleukin‐8, interferon gamma‐induced protein 10, and tumor necrosis factor α, were remarkably elevated in patients with CRC compared to those with adenomatous polyps. Although further clinical validation is required, these proteins and cytokines can be established as novel biomarkers for CRC and/or its progression from colon adenoma.  相似文献   
27.

Objective

Progranulin and C1q/TNF-related protein-3 (CTRP3) were recently discovered as novel adipokines which may link obesity with altered regulation of glucose metabolism, chronic inflammation and insulin resistance.

Research Design and Methods

We examined circulating progranulin and CTRP3 concentrations in 127 subjects with (n = 44) or without metabolic syndrome (n = 83). Furthermore, we evaluated the relationship of progranulin and CTRP3 levels with inflammatory markers and cardiometabolic risk factors, including high-sensitivity C-reactive protein (hsCRP), interleukin-6 (IL-6), estimated glomerular filtration rate (eGFR), and adiponectin serum concentrations, as well as carotid intima-media thickness (CIMT).

Results

Circulating progranulin levels are significantly related with inflammatory markers, hsCRP (r = 0.30, P = 0.001) and IL-6 (r = 0.30, P = 0.001), whereas CTRP3 concentrations exhibit a significant association with cardiometabolic risk factors, including waist circumference (r = −0.21), diastolic blood pressure (r = −0.21), fasting glucose (r = −0.20), triglyceride (r = −0.34), total cholesterol (r = −0.25), eGFR (r = 0.39) and adiponectin (r = 0.26) levels. Serum progranulin concentrations were higher in patients with metabolic syndrome than those of the control group (199.55 [179.33, 215.53] vs. 185.10 [160.30, 204.90], P = 0.051) and the number of metabolic syndrome components had a significant positive correlation with progranulin levels (r = 0.227, P = 0.010). In multiple regression analysis, IL-6 and triglyceride levels were significant predictors of serum progranulin levels (R 2 = 0.251). Furthermore, serum progranulin level was an independent predictor for increased CIMT in subjects without metabolic syndrome after adjusting for other cardiovascular risk factors (R 2 = 0.365).

Conclusions

Serum progranulin levels are significantly associated with systemic inflammatory markers and were an independent predictor for atherosclerosis in subjects without metabolic syndrome.

Trial Registration

ClinicalTrials.gov NCT01668888  相似文献   
28.
Hong MY  Lee EM  Jo YH  Park HC  Kim SR  Hwang JS  Jin BR  Kang PD  Kim KG  Han YS  Kim I 《Gene》2008,413(1-2):49-57
The 15,360-bp long complete mitogenome of Caligula boisduvalii possesses a gene arrangement and content identical to other completely sequenced lepidopteran mitogenomes, but different from the common arrangement found in most insect order, as the result of the movement of tRNA(Met) to a position 5'-upstream of tRNA Ile. The 330-bp A+T-rich region is apparently capable of forming a stem-and-loop structure, which harbors the conserved flanking sequences at both ends. Dissimilar to what has been seen in other sequenced lepidopteran insects, the initiation codon for C. boisduvalii COI appears to be TTG, which is a rare, but apparently possible initiation codon. The ATP8, ATP6, ND4L, and ND6 genes, which neighbor another PCG at their 3' end, all harbored potential sequences for the formation of a hairpin structure. This is suggestive of the importance of such structures for the precise cleavage of the mRNA of mature PCGs. Phylogenetic analyses of available sequenced species of Bombycoidea, Pyraloidea, and Tortricidea supported the morphology-based current hypothesis that Bombycoidea and Pyraloidea are monophyletic (Obtectomera). As previously suggested, Bombycidae (Bombyx mori and B. mandarina) and Saturniidae (Antheraea pernyi and C. boisduvalii) formed a reciprocal monophyletic group.  相似文献   
29.
Coxsackieviruses are important pathogens in children and the outcomes of neonatal infection can be serious or fatal. However, the outcomes of coxsackievirus infection during early gestation are not well defined. In this study, we examined the possibility of vertical transmission of coxsackievirus B3 (CVB3) and the effects of CVB3 infection on early pregnancy of ICR mice. We found that the coxsackievirus and adenovirus receptor (CAR) was highly expressed not only in embryos but also in the uterus of ICR mice. CVB3 replicated in the uterus 1 to 7 days post-infection (dpi), with the highest titer at 3 dpi. The pregnancy loss rate in mice infected with CVB3 during early gestation was 38.3%, compared to 4.7% and 2.7% in mock-infected and UV-inactivated-CVB3 infected pregnant mice, respectively. These data suggest that the uterus and embryo, which express abundant CAR, are important targets of CVB3 and that the vertical transmission of CVB3 during early gestation induces pregnancy loss.  相似文献   
30.

Objective

To analyze trends in the use of partial nephrectomy, we evaluated which individual factors of renal nephrometry score (RNS) influenced the operative approach bi-annually from 2008 to 2014.

Materials and Methods

We performed a retrospective review of renal cell carcinoma treated by surgery in 2008, 2010, 2012, and 2014. The complexity of renal masses was measured using the R.E.N.A.L. nephrometry scoring system with CT or MRI. Group comparison in terms of operation year and surgical type (partial nephrectomy versus radical nephrectomy) was performed. We developed a nomogram to quantitate the likelihood of selecting partial nephrectomy over radical nephrectomy.

Results

A total of 1106 cases (237 in 2008, 225 in 2010, 292 in 2012, and 352 in 2014) were available for the study. Over the study period, the proportion of partial nephrectomies performed increased steadily from 21.5% in 2008 to 66.5% in 2014 (p < 0.05). Furthermore, use of partial nephrectomy increased steadily in all RNS complexity groups (low, moderate, and high) (p < 0.05). In the analysis of individual components of RNS, values of the R and N components increased statistically by year in the partial nephrectomy group (p < 0.05). Average AUC was 0.920.

Conclusions

The proportion of partial nephrectomies performed sharply increased over the study period. Additionally, over the study period, more partial nephrectomies were performed for renal masses of larger size and closer to the collecting system and main renal vessels. A nomogram developed based on this recent data set provides significant predictive value for surgical decision making.  相似文献   
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