Mechanistic insights into photoinduced energy and charge transfer dynamics between magnesium-centered tetrapyrroles and carbon nanotubes.

Functionalizing single-walled carbon nanotubes (SWNTs) with light-harvesting molecules is a facile way to construct donor-acceptor nanoarchitectures with intriguing optoelectronic properties. Magnesium-centered bacteriochlorin (MgBC), chlorin (MgC), and porphyrin (MgP) are a series of tetrapyrrole macrocycles comprising a central metal and four coordinated aromatic or antiaromatic five-membered rings linked by methine units, which show excellent visible light absorption. To delineate the effects of the aromaticity of coordinated rings on the optoelectronic properties of the nanocomposites, the photoinduced energy and charge transfer dynamics between Mg-centered tetrapyrroles and SWNTs are explored. The results show that excited energy transfer (EET) can occur within MgP@SWNT ascribed to the stabilization of the highest occupied molecular orbital (HOMO) in MgP with the increase of aromatic coordinated rings, while only electron transfer can take place in MgBC@SWNT and MgC@SWNT. Non-adiabatic dynamics simulations demonstrate that electron and hole transfer from MgP to SWNT is asynchronous. The electron transfer is ultrafast with a timescale of ca. 50 fs. By contrast, the hole transfer is significantly suppressed, although it can be accelerated to some extent when using a lower excitation energy of 2.2 eV as opposed to 3.1 eV. Further analysis reveals that the large energy gaps between charge-donor and charge-acceptor states play a crucial role in regulating photoexcited state relaxation dynamics. Our theoretical insights elucidate the structure-functionality interrelations between Mg-centered tetrapyrroles and SWNTs and provide a comprehensive understanding of the underlying charge transfer mechanism within MgP@SWNT nanocomposites, which paves the way for the forthcoming development of SWNT-based photo-related functional materials with targeted applications.

Interfacial photoinduced carrier dynamics tuned by polymerization of coronene molecules encapsulated in carbon nanotubes: bridging type-I and type-II heterojunctions.

Carbon nanomaterials play important roles in modern scientific research. Integrating different carbon-based building blocks into nano-hybrid architectures not only takes full advantage of each component, but also brings in novel interfacial properties. Herein, we have employed density functional theory (DFT) calculations to investigate the effects of polymerization degree of coronene molecules encapsulated in single-walled carbon nanotubes (SWNTs) (19,0) on their interfacial properties. The present results reveal that the interfacial properties of the formed heterojunctions are remarkably regulated by the polymerization degree. For example, monomer- and dimer-encapsulated SWNTs are type-I heterojunctions in which interfacial excitation energy transfer is preferred, whereas interfacial charge carrier transfer is favorable in trimer- and polymer-encapsulated SWNTs because they are type-II heterojunctions. On the other hand, we have employed the time-domain nonadiabatic dynamics simulation approach to explore the interfacial carrier dynamics in type-II polymer-encapsulated SWNT heterojunctions. It is found that the electron and hole transfer processes are asymmetric and occur in opposite directions and at different rates. The former takes place from polymers to SWNTs in an ultrafast way (ca. 370 fs), whereas the latter occurs slowly from SWNTs to polymers (ca. 24 ps). A closer analysis uncovers the fact that the different carrier transfer rates mainly originate from the different densities of the acceptor states, energy differences and inter-state couplings between the donor and acceptor states. Finally, the present work demonstrates that the polymerization degree could act as a new regulating strategy to tune the interfacial properties of molecule-encapsulated SWNT heterojunctions.

Antioxidant epoxydon and benzolactone derivatives from the insect-associated fungus Phoma sp.

One new epoxydon ester (1) and a new benzolactone derivative (2), along with four known compounds (3-6), were isolated from the insect-associated fungus Phoma sp. Their structures were confirmed by extensive MS and NMR spectroscopic analysis and their absolute configurations were determined by a combination of modified Mosher method and Mo2(OCOCH3)4-induced electronic circular dichroism (ECD) experiments. Compounds 1 and 5 were revealed to have potent antioxidant activities, which were approximate to the potency of the positive control trolox. In addition, 1 also exhibited moderate cytotoxic effect against human MGC-803 tumor cell line.[Formula: see text].

Photoinduced Carrier Dynamics at the Interface of Pentacene and Molybdenum Disulfide.

Understanding of photoinduced interfacial carrier dynamics in organic-transition metal dichalcogenides heterostructures is very important for the enhancement of their potential photoelectronic conversion efficiencies. In this work we have used density functional theory (DFT) calculations and DFT-based fewest-switches surface-hopping dynamics simulations to explore the photoinduced hole transfer and subsequent nonadiabatic electron-hole recombination dynamics taking place at the interface of pentacene and MoS2 in pentacene@MoS2. Upon photoexcitation the electronic transition mainly occurs on the MoS2 monolayer, which corresponds to moving an electron to the MoS2 conduction band. As a result, a hole is left in the valence band. This hole state is energetically lower than certain occupied states of the pentacene molecule; thus, the interfacial hole transfer from MoS2 to pentacene is favorable in energy. In terms of nonadiabatic dynamics simulations, the hole transfer time to the HOMO-1 state of the pentacene is estimated to be about 600 fs; however, the following hole relaxation process from HOMO-1 to HOMO takes much longer time of ca. 15 ps due to the large energy gap between HOMO-1 and HOMO. Moreover, our results also show that the subsequent radiationless recombination process between the hole transferred to the pentacene molecule and the remaining electron on the MoS2 CBM needs about 10.2 ns. The computational results shed important mechanistic insights on the interfacial carrier dynamics of mixed-dimensional pentacene@MoS2. These insights could help to design excellent interfaces for organic-TMDs heterostructures.

Theoretical Insights into Interfacial Electron Transfer between Zinc Phthalocyanine and Molybdenum Disulfide.

A comprehensive understanding of interfacial charge transfer dynamics is critical for improving the optoelectronic efficiency of organic-transition metal dichalcogenide heterostructures. In this work we have employed density functional theory (DFT) and developed nonadiabatic dynamics simulation approaches to study the photoinduced electron transfer dynamics at the interface of zinc phthalocyanine (ZnPc) and molybdenum disulfide (MoS2). Our present results show that ZnPc is adsorbed in a parallel orientation on MoS2 through a weak van der Waals interaction. Photoirradiation excites an electron of ZnPc into its lowest unoccupied molecular orbital (LUMO), which is primarily located on ZnPc but has a tail on MoS2. This enhances the vibronic coupling between the LUMO of ZnPc and adiabatic states of MoS2, thereby benefiting the interfacial electron transfer. The LUMO of ZnPc is also calculated to be 0.27 eV higher than the conduction band minimum (CBM) of MoS2 so that the electron transfer from ZnPc to MoS2 is thermodynamically favorable. Further nonadiabatic dynamics simulations verify such ultrafast electron transfer and estimate its time scale of ca. 10 fs. In this process, the low-frequency out-of-plane vibration of MoS2, and low- and high-frequency in-plane and out-of-plane vibrations of ZnPc are found to play an important role in regulating this interfacial electron transfer. In-depth analysis also reveals that atomic motion induced changes of adiabatic states is a dominant factor leading to such ultrafast interfacial electron transfer. These insights could be useful for understanding charge transfer processes at interfaces of heterostructures.

The Origin of the Photoluminescence Enhancement of Gold-Doped Silver Nanoclusters: The Importance of Relativistic Effects and Heteronuclear Gold-Silver Bonds.

The weak photoluminescence of silver nanoclusters prevents their broad application as luminescent nanomaterials. Recent experiments, however, have shown that gold doping can significantly enhance the photoluminescence intensity of Ag29 nanoclusters but the molecular and physical origins of this effect remain unknown. Therefore, we have computationally explored the geometric and electronic structures of Ag29 and gold-doped Ag29-x Aux (x=1-5) nanoclusters in the S0 and S1 states. We found that 1) relativistic effects that are mainly due to the Au atoms play an important role in enhancing the fluorescence intensity, especially for highly doped Ag26 Au3 , Ag25 Au4 , and Ag24 Au5 , and that 2) heteronuclear Au-Ag bonds can increase the stability and regulate the fluorescence intensity of isomers of these gold-doped nanoclusters. These novel findings could help design doped silver nanoclusters with excellent luminescence properties.

Mechanistic Photochemistry of Methyl-4-hydroxycinnamate Chromophore and Its One-Water Complexes: Insights from MS-CASPT2 Study.

Herein we computationally studied the excited-state properties and decay dynamics of methyl-4-hydroxycinnamate (OMpCA) in the lowest three electronic states, that is, (1)ππ*, (1)nπ*, and S0 using combined MS-CASPT2 and CASSCF electronic structure methods. We found that one-water hydration can significantly stabilize and destabilize the vertical excitation energies of the spectroscopically bright (1)ππ* and dark (1)nπ* excited singlet states, respectively; in contrast, it has a much smaller effect on the (1)ππ* and (1)nπ* adiabatic excitation energies. Mechanistically, we located two (1)ππ* excited-state relaxation channels. One is the internal conversion to the dark (1)nπ* state, and the other is the (1)ππ* photoisomerization that eventually leads the system to a (1)ππ*/S0 conical intersection region, near which the radiationless internal conversion to the S0 state occurs. These two (1)ππ* relaxation pathways play distinct roles in OMpCA and its two one-water complexes (OMpCA-W1 and OMpCA-W2). In OMpCA, the predominant (1)ππ* decay route is the state-switching to the dark (1)nπ* state, while in one-water complexes, the importance of the (1)ππ* photoisomerization is significantly enhanced because the internal conversion to the (1)nπ* state is heavily suppressed due to the one-water hydration.

QM/MM Study on Mechanistic Photophysics of Alloxazine Chromophore in Aqueous Solution.

Compared with isoalloxazine, the core chromophore of biologically important flavins, alloxazine exhibits much lower fluorescence quantum yield and larger intersystem-crossing quantum yield. However, its efficient radiationless relaxation pathways are still elusive. In this work, we have used the QM(MS-CASPT2//CASSCF)/MM method to explore the mechanistic photophysics of alloxazine chromophore in aqueous solution. On the basis of the optimized minima, conical intersections, and crossing points in the lowest (1)ππ*, (1)nπ*, (3)ππ*, and (3)nπ* states, we have proposed three energetically possible nonadiabatic relaxation pathways populating the lowest (3)ππ* triplet state from the initially populated excited (1)ππ* singlet state. The first is the direct (1)ππ*→ (3)ππ* intersystem crossing via the (1)ππ*/(3)ππ* crossing point. The second is an indirect (1)ππ* → (3)ππ* intersystem crossing relayed by the dark (1)nπ* singlet state. In this route, the (1)ππ* system first decays to the (1)nπ* state via the (1)ππ*/(1)nπ* conical intersection, followed by an (1)nπ*→ (3)ππ* intersystem crossing at the (1)nπ*/(3)ππ* crossing point to arrive at the final (3)ππ* state. The third is similar to the second one; but its intersystem crossing is relayed by the (3)nπ* triplet state. The (1)ππ* system first decays to the (3)nπ* state via the (1)ππ*/(3)nπ* crossing point; the generated (3)nπ* state is then de-excited to the (3)ππ* state through the (3)nπ*→ (3)ππ* internal conversion at the (3)nπ*/(3)ππ* conical intersection. According to the classical El-Sayed rule, we suggest the second and third paths play a much more important role than the first one in the formation of the lowest (3)ππ* state.

Radiofrequency ablation following first-line transarterial chemoembolization for patients with unresectable hepatocellular carcinoma beyond the Milan criteria.

BACKGROUND: Recent studies suggest that a combination of radiofrequency ablation (RFA) and transarterial chemoembolization (TACE) may have theoretical advantages over TACE alone for treatment of hepatocellular carcinoma (HCC). The purpose of this study was to evaluate the effectiveness and safety of radiofrequency ablation following first-line TACE treatment in the management of HCC beyond the Milan Criteria. METHODS: Forty-five patients who consecutively underwent RFA following first-line TACE treatment for HCC beyond the Milan criteria were enrolled in this study. RFA was performed within 1-2 months after TACE treatment in patients who had incomplete necrotic tumor nodules. Primary effectiveness, complications, survival rates, and prognostic factors were evaluated retrospectively. RESULTS: Complete ablation was achieved in 76.2% of the lesions according to 1-month follow-up computed tomography/magnetic resonance imaging evaluation. The mean follow-up period was 30.9 months (range 3-94 months). There were no major complications after RFA therapy. The median overall survival was 29 months (range 20-38 months), with 1-, 2-, and 3-year survival of 89%, 61%, and 43%, respectively. Multivariate analysis revealed that tumor diameter (P = 0.045, hazard ratio [HR] = 0.228, 95% confidence interval [CI]: 0.054-0.968) and pretreatment serum alpha-fetoprotein level (P = 0.024, HR = 2.239, 95% CI: 1.114-4.500) were independent predictors for long-term survival. CONCLUSIONS: HCC beyond the Milan criteria can be completely and safely ablated by radiofrequency ablation following first-line TACE treatment with a low rate of complications and favorable survival outcome. Further assessment of the survival benefits of combination treatment for HCCs beyond the Milan Criteria is warranted.

Transarterial chemoembolization for hepatocellular carcinoma with portal vein tumor thrombus: a meta-analysis.

BACKGROUND: Although transarterial chemoembolization (TACE) has been used extensively for advanced hepatocellular carcinoma (HCC) with portal vein tumor thrombus (PVTT), no consensus has been reached and an evidence base for practice is lacking. This meta-analysis evaluated the efficacy and safety of TACE for treatment of HCC with PVTT. METHODS: Ovid Medline, EMBASE, Web of Knowledge, and Cochrane library databases were searched up to August 2012 for controlled trials assessing TACE in patients with PVTT. Data concerning the study design, characteristics of trials, and outcomes were extracted. Hazard ratio (HR) and 95% confidence interval (CI) were calculated using random effects models. RESULTS: Eight controlled trials involving 1601 HCC patients were included. TACE significantly improved the 6-month (HR, 0.41; 95% CI: 0.32-0.53; z, 6.28; p = 0.000) and 1-year (HR, 0.44; 95% CI: 0.34-0.57; z, 6.22; p = 0.000) overall survival of patients with PVTT compared with conservative treatment. Subgroup analyses showed that TACE was significantly effective in HCC patients whether with main portal vein (MPV) obstruction or with segmental PVTT. Fatal complications were rare, even in patients with MPV obstruction. Temporary liver decompensation and postembolization syndrome occurred frequently. However, they could be treated successfully with conservative treatment. CONCLUSIONS: TACE, as a safe treatment, has potential for incurring a survival benefit for advanced HCC with PVTT, even with MPV obstruction. Further large randomized controlled trials may be needed to confirm this result.

Herbal compound "Songyou Yin" attenuates hepatoma cell invasiveness and metastasis through downregulation of cytokines secreted by activated hepatic stellate cells.

BACKGROUND: Activated hepatic stellate cells (aHSCs) play an important role in the progression of hepatocellular carcinoma (HCC). Here, we determined if cytokines secreted in response to the herbal compound "Songyou Yin" (SYY) treatment of aHSCs could influence invasiveness and metastatic capabilities of hepatoma cells. METHODS: Primary rat hepatic stellate cells (HSCs) were isolated, activated, divided into SYY treated and untreated (nSYY) groups, and conditioned media (CM-SYY and CM-nSYY, respectively) were collected. The hepatoma cell line, McA-RH7777 was cultured for 4 weeks with SYY, CM-SYY, and CM-nSYY, designated McA-SYY, McA-SYYCM and McA-nSYYCM. The invasiveness and metastatic capabilities were evaluated using Matrigel invasion assay in vitro and pulmonary metastasis in vivo. Matrix metalloproteinase-2 (MMP-2), MMP-9, E-cadherin, N-cadherin, and vimentin protein levels in McA-SYYCM and McA-nSYYCM were evaluated by Western blot. Cytokine levels in conditioned media were tested using enzyme-linked immunosorbent assay (ELISA). RESULTS: Matrigel invasion assay indicated that the number of McA-SYYCM cells passing through the basement membrane was less than in McA-nSYYCM cells (P < 0.01). Similar results were also observed in vivo for lung metastasis. McA-SYYCM cells showed less pulmonary metastasis capabilities than McA-nSYYCM cells (P < 0.001). The reduced expression of MMP-2 and reversed epithelial to mesenchymal transition with E-cadherin upregulation, and N-cadherin and vimentin downregulation were also found in McA-SYYCM compared to McA-nSYYCM. Metastasis-promoting cytokines hepatocyte growth factor, interleukin-6, transforming growth factor-ß1, and vascular endothelial growth factor were markedly decreased in CM-SYY compared to CM-nSYY. CONCLUSIONS: SYY attenuates hepatoma cell invasiveness and metastasis capabilities through downregulating cytokines secreted by activated hepatic stellate cells.

[Effects of the Chinese herbal extract Songyou Yin on the residual hepatocellular carcinoma after chemotherapy in nude mice].

OBJECTIVE: To investigate the effects of a Chinese herbal extract Songyou Yin on residual hepatocellular carcinoma after chemotherapy in nude mice and the relevant mechanisms. METHODS: Orthotopic nude mouse models bearing residual hepatocellular carcinoma after chemotherapy was established using human liver carcinoma MHCC97L cells. Three different doses of Songyon Yin (2.1 g/kg, 4.2 g/kg and 8.4 g/kg) were administered to the mice in the trial groups by intragastric gavage, respectively. The mice in the control group were administered physiological saline. The tumor growth, metastasis and survival in the mice of each group were recorded. The corresponding mechanisms were studied. RESULTS: The pulmonary metastasis rates of the control group and 2.1g/kg, 4.2g/kg, 8.4g/kg Songyou Yin treatment group were 86.7%, 73.3%, 40.0%, and 20.0%, respectively, and the survivals of these groups were 53.83 ± 4.71, 56.50 ± 6.09, 66.67 ± 5.61, 81.17 ± 7.36 days, respectively. Compared with the mice in the control group, mice in the 4.2 g/kg, 8.4 g/kg Songyou Yin treatment groups had a lower pulmonary metastasis rate (P = 0.021 and P = 0.001, respectively) and longer survival (P = 0.002 and P = 0.001, respectively). A restoration of E-cadherin expression and a concomitant reduction of N-cadherin expression were detected in the tumors of the 4.2 g/kg and 8.4 g/kg Songyou Yin treatment groups. CONCLUSIONS: Songyou Yin effectively inhibits the invasion and metastasis of the residual hepatocellular carcinoma after chemotherapy in nude mice through attenuating the epithelia-mesenchymal transition and prolongs the survival. Songyon Yin may have potential to promote the efficacy of chemotherapy in hepatocellular carcinoma.

Near-Infrared Dual-Emission of a Thiolate-Protected Au42 Nanocluster: Excited States, Nonradiative Rates, and Mechanism.

Both DFT and TD-DFT methods are used to elaborate on the excited-state properties and dual-emission mechanism of a thiolate-protected Au42 nanocluster. A three-state model (S0, S1, and T1) is proposed with respect to the results. The intersystem crossing (ISC) process from S1 to T1 benefits from a small reorganization energy due to the similar geometric structures of S1 and T1. However, the ISC process is suppressed by relatively small spin-orbit coupling resulting from the similarity of the electronic structures of S1 and T1. As a result of the counterbalance, the ISC rate is comparable with the fluorescence emission rate. In the T1 state, the phosphorescence emission prevails the reverse ISC process back to the S1 state. Taken together, fluorescence and phosphorescence are achieved simultaneously. The present work provides deep mechanistic insights to aid the rational design of NIR dual-emissive metal nanoclusters.

[The effect of birth weight and early growth on body fat composition and insulin sensitivity].

OBJECTIVE: To investigate the effect of birth weight and early growth on body fat composition and insulin sensitivity. METHODS: The birth and growth data of 258 children of 6 to 7 years old in Guangzhou were collected from Jun.2009 to Feb. 2010. Physical and laboratory examination were preformed, which included body weight, body height and body fat composition index (body mass index (BMI), percentage of body fat (PBF), waist circumference to height ratio (WtHR), etc). Fasting blood glucose and insulin were measured. The homeostasis model assessment model for insulin resistance index (HOMA-IR) was calculated. According to birth weight, the children were divided into three groups from light to heavy: BW-I, BW-II, BW-III group. Then according to change in weight SDS between 0 and 36 months, the children were divided into three groups: changers up (CU), non-changers (NC), changers down (CD) group. The effect of birth weight and early growth on body fat composition and insulin sensitivity were analyzed. RESULTS: Change in weight SDS between 0 and 36 months was higher in BW-I group (1.06 ± 1.29) than in the BW-II group (-0.19 ± 0.94) and BW-III group (-0.10 ± 1.20) (all P values < 0.01). Birth weight of the CU group ((2.90 ± 0.47) kg) was lower than that of the NC group ((3.22 ± 0.34) kg) and the CD group ((3.57 ± 0.37) kg) (all P values < 0.01). The body fat composition index of BMI, PBF and WtHR were higher in the BW-III group ((16.35 ± 2.13) kg/m(2), (17.03 ± 5.88)%, (0.479 ± 0.033)) than in the BW-I group ((15.46 ± 2.06) kg/m(2), (14.06 ± 5.25)%, (0.459 ± 0.032)) and BW-II group ((15.47 ± 1.58) kg/m(2), (14.09 ± 5.01)%, (0.460 ± 0.025)) (P < 0.01), while there was no significant difference between the BW-I group and the BW-II group (P > 0.05). The body fat composition index of BMI, PBF and WtHR were higher in the CU group ((16.44 ± 2.20) kg/m(2), (16.51 ± 5.78)%, (0.473 ± 0.034)) than in the NC group ((15.62 ± 1.74) kg/m(2), (14.49 ± 5.30)%, (0.463 ± 0.030)) and the CD group ((15.26 ± 1.85) kg/m(2), (14.24 ± 5.54)%, (0.462 ± 0.031)) (all P values < 0.05). In the CU group, BMI, PBF and WtHR were higher in the BW-III-CU group ((18.76 ± 2.56) kg/m(2), (22.19 ± 8.28)%, (0.512 ± 0.029)) than in the BW-I-CU group ((16.04 ± 2.14) kg/m(2), (15.54 ± 5.28)%, (0.467 ± 0.034)) and BW-II-CU group ((16.70 ± 1.36) kg/m(2), (17.12 ± 4.44)%, (0.474 ± 0.017)) (all P values < 0.05), while there was no significant difference between the BW-I-CU group and the BW-II-CU group (P > 0.05). HOMA-IR was higher in the CU group (1.27 ± 0.44) than in the NC group (1.08 ± 0.31) and the CD group (1.00 ± 0.36) (all P values < 0.01). In the CU group, HOMA-IR was higher in the BW-III-CU group (1.69 ± 0.48) than in the BW-I-CU group (1.21 ± 0.41) and the BW-II-CU group (1.27 ± 0.44) (all P values < 0.01), while there was no significant difference between the BW-I-CU and BW-II-CU group (P > 0.05). CONCLUSION: According to birth weight tertile, both lower birth weight individuals with more weight change-up growth postnatal early and higher birth weight individuals had greater body fat composition in childhood. They were high-risk people of insulin resistance.

[Relative analysis of OPN and its related signal molecules in hepatocellular carcinoma].

Osteopontin (OPN) has close relationship with metastasis in hepatocellular carcinoma but its downstream signal pathways have not been well defined in hepatocellular carcinoma. The object of this study is to identify the associated signal pathways in human HCC tissues. The expressions of OPN, intergrin aV, CD44v6, P-FAK, FAK, P-Src, Src, P-ERK and P-AKT were assayed using TMA analysis. The relationship of OPN with P-ERK, P-Src and P-AKT were explored and the role in HCC metastasis was analysed. The expression levels of OPN, intergrin aV, CD44v6, P-FAK, P-Src, Src, P-ERK and P-AKT in HCC tissue were significantly higher than that in normal tissue (P value is less than 0.05). No significant difference was found between the expression levels of FAK in HCC tissue and normal tissue (P value is more than 0.05). OPN expression was significantly associated with Integrin av (P value is less than 0.01), CD44V6 (P value is less than 0.01) and P-ERK (P value is less than 0.05) but not with P-Src, P-FAK and P-AKT (P value is more than 0.05). The expressions of P-FAK (P value is less than 0.05), P-Src (P value is less than 0.01) and P-AKT (P value is less than 0.05) were significantly associated with Integrin av and the P-FAK expression was also significantly associated with CD44V6 (P value is less than 0.01). OPN promotes HCC metastasis though Integrin av/CD44V6/MAPK pathway in human HCC.

[Therapeutic efficacy and prognostic factors of sorafenib treatment in patients with unresectable primary hepatocellular carcinoma].

OBJECTIVE: To evaluate the efficacy and analyze the prognostic factors of sorafenib treatment in patient with unresectable primary hepatocellular carcinoma (HCC). METHODS: During the period from December 2005 to March 2009, 50 patients with unresectable primary HCC of Child-Pugh status A were treated with sorafenib (400 mg, Bid). The tumor response was evaluated with CT or MRI imaging every 6 - 8 weeks according to the RECIST criteria. The overall survival (OS) and time to progression (TTP) were defined as the time from administration of sorafenib to the death or the last follow up and were evaluated by Kaplan-Meier method. RESULTS: There was no PR or CR, but 28 patients (56.0%) achieved stable disease. The median follow up time was 15 months with a median OS of 14 months and median TTP of 4 months. The common adverse events were dermal reaction (68.0%, 34/50), diarrhea (52.0%, 26/50), hypertension (4.0%, 2/50), hair loss (14.0%, 7/50), myelosuppression (16.0%, 8/50), and liver dysfunction (20.0%, 10/50). However, most of the drug-related adverse events were grade I-II and reversible. The patients with lower tumor burden and without distant metastasis had better prognosis. CONCLUSION: Soafenib is effective for unresectable primary HCC with tolerable toxicity. Tumor stage is a predominant prognostic factor.

[The accuracy of combining aldosterone to renin ratio and low renin level in diagnosing primary aldosteronism].

OBJECTIVE: To evaluate the accuracy of combing serum aldosterone to plasma rennin ratio (ARR) and low renin level in diagnosing primary aldosteronism (PA). METHODS: The ratio of serum aldosterone to plasma renin was determined in 100 patients with PA and 61 patients with primary hypertension. The optimum cut-point of ARR was determined by the Receiver Operating Characteristic (ROC). The sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and Youden index of the ARR at the optimum cut-off point were calculated in a separate test. The sensitivity and specificity of combining ARR and low renin level or high aldosterone level in diagnosing PA were determined. RESULTS: The supine ROC area under the curve (AUC1) was 0.991. The erect ROC area under the curve (AUC2) was 0.988. The AUC1 and AUC2 had no significant difference (P = 0.879). But they were both different significantly from with the area under the reference line (0.5) (P = 0.000). The optimum cut-off point of supine ARR was 112.06, with 0.96, 0.95, 0.91, 19.59 and 0.04 in sensitivity, specificity, Youden index, positive likelihood ratio and negative likelihood ratio, respectively. Combining ARR and low renin level produced a sensitivity and specificity of 0.422 and 0.998, respectively, in diagnosing PA. Combining ARR and high aldosterone level produced a sensitivity and specificity of 0.854 and 0.994, respectively in diagnosing PA. The optimum cut-off point of erect ARR was 36.61, with 0.99, 0.93, 0.92, 15 and 0.01 in sensitivity, specificity, Youden index, positive likelihood ratio and negative likelihood ratio, respectively. Combining ARR and low renin level produced a sensitivity and specificity of 0.941 and 0.986, respectively, in diagnosing PA. Combining ARR and high aldosterone level produced a sensitivity and specificity of 0.604 and 0.999, respectively in diagnosing PA. CONCLUSION: Erect ARR (> or = 36.61) can be used in detecting PA. Combining ARR and low renin level improves the accuracy in diagnosing PA and reduces misdiagnosis. The method is simple and available. It can be carried out in the out-patient department.

Histone Demethylase KDM4C Is Required for Ovarian Cancer Stem Cell Maintenance.

Ovarian cancer is a highly deadly disease, which is often diagnosed at a late stage with metastases. However, most ovarian cancers relapse after surgery combined with platinum-based chemotherapy. Cancer stem cells (CSCs) are stem-like cells that possess high tumorigenic capability and display higher resistant capability against current therapies. However, our knowledge of ovarian CSCs and their molecular mechanism remains sparse. In the current study, we found that KDM4C, a histone demethylase, was required for ovarian cancer stem cell (CSC) maintenance. Depletion of KDM4C significantly reduced the CSC population and sphere formation in vitro. Moreover, we found that KDM4C can regulate the expression of stem cell factor OCT-4 via binding to its promoter. These data indicate that KDM4C is relevant for ovarian CSC maintenance and underscore its importance as a potential therapeutic target.

Boosting electrocatalytic N2 reduction by MnO2 with oxygen vacancies.

Here, we demonstrate the experimental verification of utilizing a MnO2 with oxygen vacancies (MnOx) nanowire array for high-performance and durable electrocatalytic reduction at neutral pH. Such MnOx nanoarray obtains a high rate of NH3 formation (1.63 × 10-10 mol cm-2 s-1) and a high Faradaic efficiency of 11.40%, which are much higher than those of its pristine MnO2 counterpart (2.3 × 10-11 mol cm-2 s-1; 1.96%). Density functional theory calculations demonstrate that the enhancement of N2 adsorption on the MnOx surface is due to stronger electronic interaction between the N2 molecule and the Mn6c atoms as a result of the oxygen vacancy. This work opens up a new avenue to explore oxygen nonstoichiometry toward the rational design of N2-fixing electrocatalysts with boosted performance for applications.

Design and Evaluation of a Novel Multiplex Real-Time PCR Melting Curve Assay for the Simultaneous Detection of Nine Sexually Transmitted Disease Pathogens in Genitourinary Secretions.

Background: Sexually transmitted diseases (STD) are a major cause of infertility, long-term disability, ectopic pregnancy, and premature birth. Therefore, the development of fast and low-cost laboratory STD diagnostic screening methods will contribute to reducing STD-induced reproductive tract damage and improve women's health worldwide. In this study, we evaluated a novel multiplex real-time PCR melting curve assay method for the simultaneous detection of 9 STD pathogens, including Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma genitalium, Trichomonas vaginalis, Mycoplasma hominis, Ureaplasma urealyticum, Ureaplasma parvum, and herpes simplex virus. Methods: The analytical performance of the method, including its limit of detection (LOD), specificity, repeatability, and effect on different DNA extraction kits were evaluated. Additionally, we obtained 1,328 clinical specimens from 3 hospitals to detect the 9 STD pathogens using multiplex real-time PCR melting curve and Sanger sequencing, to evaluate the sensitivity, specificity, and consistency of the assay method. Results: The results showed that the analytical sensitivity of the novel multiplex real-time PCR melting curve assay is very excellent, with LOD of DNA corresponding to <200 copies/µL for the DNA of the 9 STDs and 1.00 × 104 color change unit /ml for those of UU and UP. Additionally, this assay demonstrated excellent analytical specificity, excellent repeatability, and its results had no effect of different DNA extraction kits. The performance, in terms of sensitivity (91.06-100%) and specificity (99.14-100%), was remarkable, since the consistency between it and Sanger sequencing was more than 0.85 in the clinic. Conclusion: The novel multiplex real-time PCR melting curve assay method has high sensitivity and specificity, relatively low cost, and simple to use for the simultaneous detection of 9 STD pathogens in genitourinary secretions.