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131.
Cancer is the second leading cause of deaths worldwide. Despite concerted efforts to improve the current therapies, the prognosis of cancer remains dismal. Highly selective or specific blocking of only one of the signaling pathways has been associated with limited or sporadic responses. Using targeted agents to inhibit multiple signaling pathways has emerged as a new paradigm for anticancer treatment. Icariside II, a flavonol glycoside, is one of the major components of Traditional Chinese Medicine Herba epimedii and possesses multiple biological and pharmacological properties including anti-inflammatory, anti-osteoporosis, anti-oxidant, anti-aging, and anticancer activities. Recently, the anticancer activity of Icariside II has been extensively investigated. Here, in this review, our aim is to give our perspective on the current status of Icariside II, and discuss its natural sources, anticancer activity, molecular targets and the mechanisms of action with specific emphasis on apoptosis pathways which may help the further design and conduct of preclinical and clinical trials.Icariside II has been found to induce apoptosis in various human cancer cell lines of different origin by targeting multiple signaling pathways including STAT3, PI3K/AKT, MAPK/ERK, COX-2/PGE2 and β-Catenin which are frequently deregulated in cancers, suggesting that this collective activity rather than just a single effect may play an important role in developing Icariside II into a potential lead compound for anticancer therapy. This review suggests that Icariside II provides a novel opportunity for treatment of cancers, but additional investigations and clinical trials are still required to fully understand the mechanism of therapeutic effects to further validate it in anti-tumor therapy.  相似文献   
132.
133.

Background

Effective management of patients with diabetic foot infection is a crucial concern. A delay in prescribing appropriate antimicrobial agent can lead to amputation or life threatening complications. Thus, this electronic nose (e-nose) technique will provide a diagnostic tool that will allow for rapid and accurate identification of a pathogen.

Results

This study investigates the performance of e-nose technique performing direct measurement of static headspace with algorithm and data interpretations which was validated by Headspace SPME-GC-MS, to determine the causative bacteria responsible for diabetic foot infection. The study was proposed to complement the wound swabbing method for bacterial culture and to serve as a rapid screening tool for bacteria species identification. The investigation focused on both single and poly microbial subjected to different agar media cultures. A multi-class technique was applied including statistical approaches such as Support Vector Machine (SVM), K Nearest Neighbor (KNN), Linear Discriminant Analysis (LDA) as well as neural networks called Probability Neural Network (PNN). Most of classifiers successfully identified poly and single microbial species with up to 90% accuracy.

Conclusions

The results obtained from this study showed that the e-nose was able to identify and differentiate between poly and single microbial species comparable to the conventional clinical technique. It also indicates that even though poly and single bacterial species in different agar solution emit different headspace volatiles, they can still be discriminated and identified using multivariate techniques.  相似文献   
134.
Vibrioses are the predominant bacterial infections in marine shrimp farms. Vibrio nigripulchritudo is an emerging pathogen of the cultured shrimp Litopenaeus stylirostris in New Caledonia and other regions in the Indo‐Pacific. The molecular determinants of V. nigripulchritudo pathogenicity are unknown; however, molecular epidemiological studies have revealed that recent pathogenic V. nigripulchritudo isolates from New Caledonia all cluster into a monophyletic clade and contain a small plasmid, pB1067. Here, we report that a large plasmid, pA1066 (247 kb), can also serve as a marker for virulent V. nigripulchritudo, and that an ancestral version of this plasmid was likely acquired prior to other virulence‐linked markers. Additionally, we demonstrate that pA1066 is critical for the full virulence of V. nigripulchritudo in several newly developed experimental models of infection. Plasmid pB1067 also contributes to virulence; only strains containing both plasmids induced the highest level of shrimp mortality. Thus, it appears that these plasmids, which are absent from non‐pathogenic isolates, may be driving forces, as well as markers, for the emergence of a pathogenic lineage of V. nigripulchritudo.  相似文献   
135.
136.
Adsorption is an environmental friendly process for removal and/or recovery of heavy metals from wastewater. In recent years, it has been substantiated as a popular technique to treat industrial waste effluents, with significant advantages. In this work, batchwise removal of chromium (III) ions from water by Polyalthia longifolia leaves was studied as a function of adsorbent dose, pH, contact time, and agitation speed. Surface characteristics of the leaves were evaluated by recording IR spectra. The Langmuir, Freundlich, and Temkin adsorption isotherms were employed to explain the sorption process. It was found that one gram of leaves can remove 1.87 mg of trivalent chromium when working at pH 3.0. It has been concluded that Polyalthia longifolia leaves can be used as cost-effective and benign adsorbents for removal of Cr(III) ions from wastewater.  相似文献   
137.
A novel, precise, accurate and rapid isocratic reversed-phase high performance liquid chromatographic/ultraviolet (RP-HPLC/UV) method was developed, optimized and validated for simultaneous determination of rosuvastatin and atorvastatin in human serum using naproxen sodium as an internal standard. Effect of different experimental parameters and various particulate columns on the analysis of these analytes was evaluated. The method showed adequate separation for rosuvastatin and atorvastatin and best resolution was achieved with Brownlee analytical C18 column (150×4.6 mm, 5 μm) using methanol-water (68:32, v/v; pH adjusted to 3.0 with trifluoroacetic acid) as a mobile phase at a flow rate of 1.5 ml/min and wavelength of 241 nm. The calibration curves were linear over the concentration ranges of 2.0-256 ng/ml for rosuvastatin and 3.0-384 ng/ml for atorvastatin. The lower limit of detection (LLOD) and lower limit of quantification (LLOQ) for rosuvastatin were 0.6 and 2.0 ng/ml while for atorvastatin were 1.0 and 3.0ng/ml, respectively. All the analytes were separated in less than 7.0 min. The proposed method could be applied for routine laboratory analysis of rosuvastatin and atorvastatin in human serum samples, pharmaceutical formulations, drug-drug interaction studies and pharmacokinetics studies.  相似文献   
138.
A fast, simple, and a reliable high-performance liquid chromatography linked with electrochemical detector (HPLC-ECD) method for the assessment of lipoic acid (LA) and dihydrolipoic acid (DHLA) in plasma was developed using naproxen sodium as an internal standard (IS) and validated according to standard guidelines. Extraction of both analytes and IS from plasma (250 μl) was carried out with a single step liquid-liquid extraction applying dichloromethane. The separated organic layer was dried under stream of nitrogen at 40°C and the residue was reconstituted with the mobile phase. Complete separation of both compounds and IS at 30°C on Discovery HS C18 RP column (250 mm × 4.6 mm, 5 μm) was achieved in 9 min using acetonitrile: 0.05 M phosphate buffer (pH 2.4 adjusted with phosphoric acid) (52:48, v/v) as a mobile phase pumped at flow rate of 1.5 ml min(-1) using electrochemical detector in DC mode at the detector potential of 1.0 V. The limit of detection and limit of quantification for lipoic acid were 500 pg/ml and 3 ng/ml, and for dihydrolipoic acid were 3 ng/ml and 10 ng/ml, respectively. The absolute recoveries of lipoic acid and dihydrolipoic acid determined on three nominal concentrations were in the range of 93.40-97.06, and 93.00-97.10, respectively. Similarly coefficient of variations (% CV) for both intra-day and inter-day were between 0.829 and 3.097% for lipoic acid and between 1.620 and 5.681% for dihydrolipoic acid, respectively. This validated method was applied for the analysis of lipoic acid/dihydrolipoic acid in the plasma of human volunteers and will be used for the quantification of these compounds in patients with oxidative stress induced pathologies.  相似文献   
139.

Background

A recently discovered occult HCV entity reported by various investigators seems to be highly controversial. Especially, the clinical significance of these findings remains uncertain. For optimal outcome of antiviral therapy, investigation of occult HCV needs a broad-based probe in order to investigate the results of viral therapy and its host/viral interaction. The current study was aimed at determining the prevalence of occult HCV in peripheral blood lymphocytes of predominantly genotype 3 HCV-infected patients after completion of antiviral therapy and to investigate long term outcomes in the presence or absence of PBMC positivity.

Method

A total of 151 chronic, antiHCV and serum RNA-positive patients were enrolled in the study. Patients with a complete virological response at the end of treatment were screened for the presence of viral RNA in their PBMCs and were followed for up to one year for the presence of serum and PBMC viral genomic RNA.

Results

Out of 151 patients, 104 (70%) responded to the prescribed interferon treatment and showed viral-clearance from serum. These were screened for the presence of genomic RNA in their PBMCs. Sixteen samples were PBMC-positive for viral RNA at the end of treatment (EOT). All these patients had also cleared the virus from peripheral blood cells after the 6-12 month follow-up study.

Conclusion

True occult hepatitis C virus does not exist in our cohort. Residual viremia at the EOT stage merely reflects a difference in viral kinetics in various compartments that remains a target of immune response even after the end of antiviral therapy and is eventually cleared out at the sustained viral response (SVR).  相似文献   
140.
Hybrid identification of 16 sunflower hybrids was confirmed using simple-sequence repeat methodology. Of 20 specific simple-sequence repeat primers, 18 authenticated the purity of these hybrids; the remaining two specific primer pairs gave ambiguous DNA fragments. The results indicate that simple-sequence repeat analysis for the identification of hybrids derived from the crossing of different inbred sunflower lines can improve the accuracy of selection, save time and reduce cost.  相似文献   
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