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1.
The therapeutic effects of photodynamic therapy and hyperthermia on mice bearing subcutaneous tumors were investigated. Ehrlich ascites tumor cells (1 x 10(7)) were implanted subcutaneously into the femoral area of BALB/c mice. A total of 134 tumor-bearing mice were treated with photodynamic therapy, i.e., administration of laser irradiation (514.5 nm, 112.5 mW/cm2 for 11.12 min with a total energy 75 J/cm2) after injection (i.p.) of hematoporphyrin derivative (HPD, 7.5 and 10.0 mg/kg body weight) and/or hyperthermia (by electric heating needles to 44 and 45 degrees C for 30 min) once a day for three successive days. The results revealed that the therapeutic effects of the combination of photodynamic therapy and hyperthermia were improved when compared with photodynamic therapy or hyperthermia alone. A combination of photodynamic therapy (10.0 mg HPD/kg body weight and 75 J/cm2 of total laser irradiation energy) and hyperthermia (44 degrees C for 30 min) had the best therapeutic effect, indicating that the mortality rate within 120 days (MR120) was 12.5% and the mean survival time (MST120) was 113.8 days.  相似文献   
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Plasmid profiles of strains of Lactobacillus curvatus and L. sake isolated from meat or sauerkraut were analysed to investigate plasmid homology and distribution in relation to the ecology of these organisms in fermenting foods. A hybridisation probe was constructed by cloning of pLc2, a cryptic, 2.6-kbp plasmid from L. curvatus LTH683, into the Escherichia coli plasmid pRV50. In Southern hybridisations with the digoxygenine labeled pLc2 probe, pLc2-related small plasmids were frequently detected in meat-borne strains of L. casei subsp. pseudoplantarum, L. curvatus, L. sake, L. alimentarius, L. farciminis and L. halotolerans and in L. curvatus and L. sake isolated from sauerkraut. Among 27 Lactobacillus type strains originally isolated from habitats other than meat this type of homology was detected only with plasmids of L. buchneri and L. mali. Restriction-enzyme mapping of six small cryptic plasmids from L. curvatus and L. sake revealed strong structural homology but no similarity to previously characterized plasmids of lactobacilli. The presence of a variable region in addition to a conserved one and the occurrence of deletions during cloning of pLc2 suggest that vectors derived from these plasmids are likely to be structurally unstable.  相似文献   
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Kinases play fundamental roles in the brain. Through complex signaling pathways, kinases regulate the strength of protein:protein interactions (PPI) influencing cell cycle, signal transduction, and electrical activity of neurons. Changes induced by kinases on neuronal excitability, synaptic plasticity and brain connectivity are linked to complex brain disorders, but the molecular mechanisms underlying these cellular events remain for the most part elusive. To further our understanding of brain disease, new methods for rapidly surveying kinase pathways in the cellular context are needed. The bioluminescence-based luciferase complementation assay (LCA) is a powerful, versatile toolkit for the exploration of PPI. LCA relies on the complementation of two firefly luciferase protein fragments that are functionally reconstituted into the full luciferase enzyme by two interacting binding partners. Here, we applied LCA in live cells to assay 12 kinase pathways as regulators of the PPI complex formed by the voltage-gated sodium channel, Nav1.6, a transmembrane ion channel that elicits the action potential in neurons and mediates synaptic transmission, and its multivalent accessory protein, the fibroblast growth factor 14 (FGF14). Through extensive dose-dependent validations of structurally-diverse kinase inhibitors and hierarchical clustering, we identified the PI3K/Akt pathway, the cell-cycle regulator Wee1 kinase, and protein kinase C (PKC) as prospective regulatory nodes of neuronal excitability through modulation of the FGF14:Nav1.6 complex. Ingenuity Pathway Analysis shows convergence of these pathways on glycogen synthase kinase 3 (GSK3) and functional assays demonstrate that inhibition of GSK3 impairs excitability of hippocampal neurons. This combined approach provides a versatile toolkit for rapidly surveying PPI signaling, allowing the discovery of new modular pathways centered on GSK3 that might be the basis for functional alterations between the normal and diseased brain.  相似文献   
4.
Prior studies of upper gastrointestinal bleeding (UGIB) and acute myocardial infarction (AMI) are small, and long-term effects of UGIB on AMI have not been delineated. We investigated whether UGIB in patients diagnosed with coronary artery disease (CAD) increased their risk of subsequent AMI. This was a population-based, nested case-control study using Taiwan’s National Health Insurance Research Database. After propensity-score matching for age, gender, comorbidities, CAD date, and follow-up duration, we identified 1,677 new-onset CAD patients with AMI (AMI[+]) between 2001 and 2006 as the case group and 10,062 new-onset CAD patients without (AMI[−]) as the control group. Conditional logistic regression was used to examine the association between UGIB and AMI. Compared with UGIB[−] patients, UGIB[+] patients had twice the risk for subsequent AMI (adjusted odds ratio [AOR] = 2.08; 95% confidence interval [CI], 1.72–2.50). In the subgroup analysis for gender and age, UGIB[+] women (AOR = 2.70; 95% CI, 2.03–3.57) and patients < 65 years old (AOR = 2.23; 95% CI, 1.56–3.18) had higher odds of an AMI. UGIB[+] AMI[+] patients used nonsignificantly less aspirin than did UGIB[−] AMI[+] patients (27.69% vs. 35.61%, respectively). UGIB increased the risk of subsequent AMI in CAD patients, especially in women and patients < 65. This suggests that physicians need to use earlier and more aggressive intervention to detect UGIB and prevent AMI in CAD patients.  相似文献   
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Hepatitis C virus (HCV) infection-induced oxidative stress is a major risk factor for the development of HCV-associated liver disease. Sulforaphane (SFN) is an antioxidant phytocompound that acts against cellular oxidative stress and tumorigenesis. However, there is little known about its anti-viral activity. In this study, we demonstrated that SFN significantly suppressed HCV protein and RNA levels in HCV replicon cells and infectious system, with an IC50 value of 5.7 ± 0.2 μM. Moreover, combination of SFN with anti-viral drugs displayed synergistic effects in the suppression of HCV replication. In addition, we found nuclear factor erythroid 2-related factor 2 (Nrf2)/HO-1 induction in response to SFN and determined the signaling pathways involved in this process, including inhibition of NS3 protease activity and induction of IFN response. In contrast, the anti-viral activities were attenuated by knockdown of HO-1 with specific inhibitor (SnPP) and shRNA, suggesting that anti-HCV activity of SFN is dependent on HO-1 expression. Otherwise, SFN stimulated the phosphorylation of phosphoinositide 3-kinase (PI3K) leading Nrf2-mediated HO-1 expression against HCV replication. Overall, our results indicated that HO-1 is essential in SFN-mediated anti-HCV activity and provide new insights in the molecular mechanism of SFN in HCV replication.  相似文献   
7.
We investigated the hypothesis that cerebral prostanoid and peptidoleukotriene (LTs) (LTC4/D4/E4/F4) synthesis are increased during postischemic reperfusion of newborn pig brains. Prostanoids and LTs extracted from brain tissue were determined by RIA in sham-control piglets and at 1h, 3h, or 12h after a 20-min period of total cerebral ischemia. During reperfusion following ischemia, all regional brain tissue (cerebrum, brain stem and cerebellum) prostanoids (6-keto-PGF1 alpha, TXB2, PGE2 and PGF2 alpha) were increased at 1h compared with those in sham-control piglets. Only cerebral and brain stem 6-keto-PGF1 alpha and cerebral TXB2 remained elevated at 3h postischemia and all prostanoids returned to control levels by 12h postischemia. Brain tissue LTs were lower than prostanoids and were not altered 1, 3, or 12h following ischemia. These data indicate that 1) newborn pig brain tissue prostanoids are increased initially, and then returned to control levels at later stages of reperfusion following ischemia; 2) LTs are present in newborn pig brain tissue, but are not increased by ischemia/reperfusion injury and therefore probably do not play a significant role in cerebral ischemia-reperfusion injury.  相似文献   
8.
Time course studies of carotenoid production and of mycelial growth in liquid cultures of Phycomyces blakesleeanus wild type [NRRL 1555 (?)], red mutants C9, C10 and C13 and the heterokaryon C2 * C9 are reported. The ratios of the concentrations of lycopene, γ-carotene and β-carotene in the red mutant C13 and in the heterokaryon C2 * C9 during the growth periods were measured. In these strains the concentration of lycopene is close to its final value after 2 days of growth, at a time at which β-carotene is just beginning to be produced. It is suggested that the β-carotene produced late is possibly synthesized via β-zeacarotene.  相似文献   
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