Ultralow-frequency Raman system down to 10 cm(-1) with longpass edge filters and its application to the interface coupling in t(2+2)LGs.

Ultralow-frequency (ULF) Raman spectroscopy becomes increasingly important in the area of two-dimensional (2D) layered materials; however, such measurement usually requires expensive and nonstandard equipment. Here, the measurement of ULF Raman signal down to 10 cm(-1) has been realized with high throughput by combining a kind of longpass edge filters with a single monochromator, which are verified by the Raman spectrum of L-cystine using three laser excitations. Fine adjustment of the angle of incident laser beam from normal of the longpass edge filters and selection of polarization geometry are demonstrated how to probe ULF Raman signal with high signal-to-noise. Davydov splitting of the shear mode in twisted (2+2) layer graphenes (t(2+2)LG) has been observed by such system in both exfoliated and transferred samples. We provide a direct evidence of twist-angle dependent softening of the shear coupling in t(2+2)LG, while the layer-breathing coupling at twisted interfaces is found to be almost identical to that in bulk graphite. This suggests that the exfoliation and transferring techniques are enough good to make a good 2D heterostructures to demonstrate potential device application. This Raman system will be potentially applied to the research field of ULF Raman spectroscopy.

Sorafenib combined with percutaneous radiofrequency ablation for the treatment of medium-sized hepatocellular carcinoma.

OBJECTIVE: Sorafenib, an oral multikinase inhibitor, is the proved therapy method for patients with advanced hepatocellular carcinoma (HCC). Based on heat delivery, Radiofrequency ablation (RFA) has been found to achieve complete neoplasm necrosis. It is the most widely performed percutaneous therapy for HCC. However, Study associated combined Sorafenib with RFA therapy for patients with advanced HCC has never been reported. The aim of present study is to explore the efficacy and safety of sorafenib combined with RFA therapy for the patients with medium-sized HCC. PATIENTS AND METHODS: A total of 62 patients diagnosed as HCC were involved in this study. All patients were randomly assigned to sorafenib and RFA (n=30) or RFA-alone (n=32) treatment groups. Treatment outcomes, including recurrence rates, time to progression (TTP) and adverse reactions induced by sorafenib were observed and recorded to assess the efficacy and safety of the combination method. RESULTS: During the overall follow-up period, the recurrence rate of the combination subgroup was 56.7% (17/30), and that of the RFA-alone subgroup was 87.5% (28/32) (p < 0.01). The median TTP was 17.0 months in the combination therapy vs. 6.1 months in the RFA-alone (p < 0.05). Hand-foot skin reactions were reported by 83.3% (25/30) of patients and 46.7% (14/30) reported diarrhea while the most adverse events (AEs) were mild to moderate in the combination subgroup. CONCLUSIONS: Sorafenib combined with RFA significantly decreased recurrence rates and prolonged the survival time of medium-sized HCC patients. The combination therapy is safer and more effective than the control without unexpected side effects. Furthermore, the earlier application, the better results were.

Molecular characterization of photosensitizer-mediated photodynamic therapy by gene expression profiling.

Photodynamic therapy (PDT) is a novel cancer treatment based on the tumor-specific accumulation of a photosensitizer followed by irradiation with visible light, which induces selective tumor cell death via production of reactive oxygen species. To elucidate the underlying mechanisms, microarray analysis was used to analyze the changes in gene expression patterns during PDT induced by various photosensitizers. Cancer cells were subjected to four different photosensitizer-mediated PDT and the resulting gene expression profiles were compared. We identified many differentially expressed genes reported previously as well as new genes for which the functionfunctions in PDT are still unclear. Our current results not only advance the general understanding of PDT but also suggest that distinct molecular mechanisms are involved in different photosensitizer-mediated PDT. Elucidating the signaling mechanisms in PDT will provide information to modulate the antitumor effectiveness of PDT using various photosensitizers.

Hydration-dependent dynamics of deeply cooled water under strong confinement.

We have measured the hydration-level dependence of the single-particle dynamics of water confined in the ordered mesoporous silica MCM-41. The dynamic crossover observed at full hydration is absent at monolayer hydration. The monolayer dynamics are significantly slower than those of water in a fully hydrated pore at ambient temperatures. At low temperatures, the opposite is found to be true. These results underscore the importance of water's tetrahedral hydrogen-bond network in accounting for its low temperature dynamic properties.

Identification of human UGT isoforms responsible for glucuronidation of efavirenz and its three hydroxy metabolites.

Uridine 5'-diphosphate-glucuronosyltransferases (UGTs) involved in the glucuronide formation of efavirenz (EFV) and its three hydroxy metabolites, 8-hydroxyefavirenz (8-OH EFV), 7-hydroxyefavirenz (7-OH EFV), and 8,14-dihydroxyefavirenz (8,14-diOH EFV), were assessed. Among 12 recombinant UGT isoforms tested, only UGT2B7 showed catalytic activity in the formation of EFV-N-glucuronide (EFV-G) as previously reported. On the other hand, almost all UGT isoforms were involved in the glucuronidation of the three hydroxy metabolites, although their relative contribution is unclear. The catalytic activities in the formation of EFV-G by 17 different human liver microsomes exhibit a more than 40-fold inter-individual variability, whereas those of glucuronidation of the three hydroxy metabolites showed almost identical activity. The formation of EFV-G showed a significant correlation (r = 0.920; p < 0.0001) with UGT2B7-catalysed azidothymidine glucuronidation in 17 different human liver microsomes. Furthermore, fluconazole, a known UGT2B7 inhibitor, potently inhibited the formation of EFV-G up to 80%. This suggests that EFV might be a specific UGT2B7 substrate in vitro. This is the first study identifying specific UGT isozymes that glucuronidate EFV and its three hydroxy metabolites. Continued identification and characterisation of these pathways may help reduce adverse effects such as CNS toxicity in EFV therapy.

Contribution of cytochrome P450 3A4 and 3A5 to the metabolism of atorvastatin.

Atorvastatin is a 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor that is mainly metabolized by cytochrome P450 (CYP) 3A4. A recent study showed that the lipid-lowering effect of statins is affected by the CYP3A5 polymorphism. Therefore, it was investigated whether CYP3A5 contributes to the metabolism of atorvastatin. Two metabolites of atorvastatin, para- and ortho-hydroxyatorvastatin, were produced by human liver microsomes and human recombinant CYP3A enzymes, and the enzyme kinetic pattern exhibited substrate inhibition. The intrinsic clearance (CL(int)) rates of para- and ortho-hydroxyatorvastatin by CYP3A4 were 2.4- and 5.0-fold of the respective CL(int) rates of CYP3A5, indicating that CYP3A4 is the major P450 isoform responsible for atorvastatin metabolism. These results suggest that atorvastatin is preferentially metabolized by CYP3A4 rather than by CYP3A5, and thus the genetic CYP3A5 polymorphism might not be an important factor in the inter-individual variation of atorvastatin disposition and pharmacodynamics in human.

In vitro metabolism of a novel PPAR gamma agonist, KR-62980, and its stereoisomer, KR-63198, in human liver microsomes and by recombinant cytochrome P450s.

1. KR-62980 and its stereoisomer KR-63198 are novel and selective peroxisome proliferator-activated receptor gamma (PPAR gamma) modulators with activity profiles different from that of rosiglitazone. This study was performed to identify the major metabolic pathways for KR-62980 and KR-63198 in human liver microsomes. 2. Human liver microsomal incubation of KR-62980 and KR-63198 in the presence of a beta-nicotinamide adenine dinucleotide phosphate (NADPH)-generating system resulted in hydroxy metabolite formation. In addition, the specific cytochrome P450s (CYPs) responsible for KR-62980 and KR-63198 hydroxylation were identified by using a combination of chemical inhibition in human liver microsomes and metabolism by recombinant P450s. It is shown that CYP1A2, CYP2D6, CYP3A4, and CYP3A5 are the predominant enzymes in the hydroxylation of KR-62980 and KR-63198. 3. The intrinsic clearance through hydroxylation was consistently and significantly higher for KR-62980 than for KR-63198, indicating metabolic stereoselectivity (CL(int) of 0.012 +/- 0.001 versus 0.004 +/- 0.001 microl min(-1) pmol(-1) P450, respectively). 4. In a drug-drug interaction study, KR-62980 and KR-63198 had no effect on the activities of the P450s tested (IC(50) > 50 microM), suggesting that in clinical interactions between KR-62980 and KR-63198 the P450s tested would not be expected.

Group B streptococcal soft tissue infections in non-pregnant adults.

Skin and soft tissue infections are the most common presentations of invasive Streptococcus agalactiae infections. This study reviewed 71 patients in a medical centre in southern Taiwan with S. agalactiae soft tissue infections. The mortality rate was 7%, and 11% of patients lost their extremities following extensive tissue necrosis. Critical illness and the presence of cutaneous ulceration heralded a fatal prognosis. Risk-factors for amputation of limbs included advanced age, cutaneous ulceration and polymicrobial infection. It was concluded that invasive S. agalactiae soft tissue infections, as with infections caused by Streptococcus pyogenes, can also lead to substantial morbidity and mortality in non-pregnant adults.

Northridge earthquake damage caused by geologic focusing of seismic waves

Despite being located 21 kilometers from the epicenter of the 1994 Northridge earthquake (magnitude 6.7), the city of Santa Monica experienced anomalously concentrated damage with Mercalli intensity IX, an intensity as large as that experienced in the vicinity of the epicenter. Seismic records from aftershocks suggest that the damage resulted from the focusing of seismic waves by several underground acoustic lenses at depths of about 3 kilometers, formed by the faults that bound the northwestern edge of the Los Angeles basin. The amplification was greatest for high-frequency waves and was less powerful at lower frequencies, which is consistent with focusing theory and finite-difference simulations.