Highly Anisotropic Dirac Fermions in Square Graphynes

We predict a family of 2D carbon (C) allotropes, square graphynes (S-graphynes) that exhibit highly anisotropic Dirac fermions, using first-principle calculations within density functional theory. They have a square unit-cell containing two sizes of square C rings. The equal-energy contour of their 3D band structure shows a crescent shape, and the Dirac crescent has varying Fermi velocities from 0.6 × 10(5) to 7.2 × 10(5) m/s along different k directions. Near the Fermi level, the Dirac crescent can be nicely expressed by an extended 2D Dirac model Hamiltonian. Furthermore, tight-binding band fitting reveals that the Dirac crescent originates from the next-nearest-neighbor interactions between C atoms. S-graphynes may be used to build new 2D electronic devices taking advantages of their highly directional charge transport.

Management of hepatocellular carcinoma rupture in the caudate lobe

AIM: To demonstrate that caudate lobectomy is a valid treatment in cases of hepatocellular carcinoma (HCC) rupture in the caudate lobe based on our experience with the largest case series reported to date.

METHODS: A retrospective study of eight patients presenting with spontaneous rupture and hemorrhage of HCC in the caudate lobe was conducted. Two patients underwent ineffective transarterial embolization preoperatively. Caudate lobectomy was performed in all eight patients. Bilateral approach was taken in seven cases for isolated complete caudate lobectomy. Left-sided approach was employed in one case for isolated partial caudate lobectomy. Transarterial chemoembolization was performed postoperatively in all patients.

RESULTS: Caudate lobectomy was successfully completed in all eight cases. The median time delay from the diagnosis to operation was 5 d (range: 0.25-9). Median operating time was 200 min (range: 120-310) with a median blood loss of 900 mL (range: 300-1500). Five patient remained in long-term follow-up, with one patient becoming lost to follow-up at 3 years and two patients currently alive at 7 and 19 mo. One patient required reoperation due to recurrence. Gamma knife intervention was performed for brain metastasis in another case. Two patients survived for 10 and 84 mo postoperatively, ultimately succumbing to multiple organ metastases.

CONCLUSION: Caudate lobectomy is the salvage choice for HCC rupture in the caudate lobe. Local anatomy and physiologic features of the disease render caudate lobectomy a technically difficult operation. Postponement of surgical intervention is thus recommended while the rupture remains hemodynamically stable until an experienced surgeon becomes available. Prognosis is confounded by numerous factors, but long-term survival can be expected in the majority of cases.

DNA-caged gold nanoparticles for controlled release of doxorubicin triggered by a DNA enzyme and pH

DNA polyhedron-caged AuNPs were self-assembled using four-point-star DNAs, with three strands hybridizing to each other and the fourth strand attaching to the AuNPs. The caged AuNPs can act as doxorubicin nanocarriers; a DNA enzyme and pH can trigger controlled release.

Near-infrared-responsive gold nanorod/liquid crystalline elastomer composites prepared by sequential thiol-click chemistry

A novel NIR-responsive GNR/LCE composite fiber material with a very low Au loading-level (0.09 wt%) is prepared by a three-step sequential thiol-click chemistry approach.

Diurnal and temporal variations of water-soluble dicarboxylic acids and related compounds in aerosols from the northern vicinity of Beijing: implication for photochemical aging during atmospheric transport

Aerosol samples were collected in autumn 2007 on day- and nighttime basis in the northern receptor site of Beijing, China. The samples were analyzed for total carbon (TC) and water-soluble dicarboxylic acids (C2-C12), oxocarboxylic acids (C2-C9), glyoxal and methylglyoxal to better understand the photochemical aging of organic aerosols in the vicinity of Beijing. Concentrations of TC are 50% greater in daytime when winds come from Beijing than in nighttime when winds come from the northern forest areas. Most diacids showed higher concentrations in daytime, suggesting that the organics emitted from the urban Beijing and delivered to the northern vicinity in daytime are subjected to photo-oxidation to result in diacids. However, oxalic acid (C2), which is the most abundant diacid followed by C3 or C4, became on average 30% more abundant in nighttime together with azelaic, ω-oxooctanoic and ω-oxononanoic acids, which are specific oxidation products of biogenic unsaturated fatty acids. Methylglyoxal, an oxidation product of isoprene and a precursor of oxalic acid, also became 29% more abundant in nighttime. Based on a positive correlation between C2 and glyoxylic acid (ωC2) in nighttime when relative humidity significantly enhanced, we propose a nighttime aqueous phase production of C2 via the oxidation of ωC2. We found an increase in the contribution of diacids to TC by 3 folds during consecutive clear days. This study demonstrates that diacids and related compounds are largely produced in the northern vicinity of Beijing via photochemical processing of organic precursors emitted from urban center and forest areas.

[Literature review on premarketing and postmarketing evidence of xiyanping injection]

This article systematically summarizes the non-clinical safety studies, pharmacological studies and postmarketing safety studies of Xiyanping injection based on literature. These studies include acute toxicity test, long-term toxicity test, reproductive toxicity test, active and passive anaphylaxis test, curative mechanism study, clinical trials of effectiveness, active surveillance, security analysis of passive monitoring data, the real world analysis of hospital information system (HIS) data, literature analysis, etcetera This article also analysis the relationship of the different evidence, summarizes the strategy of the researches, in order to make it to be a reference for making a systemic research program of traditional Chinese medicine injection.

[Clinical analysis on combined medication in patients of acute pancreatitis in real world]

OBJECTIVE

To study the characteristics and regular pattern of the medicine in common use and combined medication in patients of acute pancreatitis in real world.

METHOD

Collect the information of 5 433 acute pancreatitis patients in 19 grade IIIA general hospitals in China, analysis by descriptive statistics and association rule.

RESULT

In the 5 433 patients of acute pancreatitis, the glycyrrhizic acid injection and somatostatin are the frequency top used Chinese traditional and western medication. Glycyrrhizic acid injection, somatostatin and insulin are the frequency top used drug combination pattern.

CONCLUSION

The Chinese and western integrative medicine drug use pattern are accord with the clinical guideline of acute panceatitis. The hepatic and renal function, blood routine and coagulation function should be monitored when the medicines are used.

[Research and practice about risk control of shenfu injection]

Shenfu injection is developed by improving dosage form of ancient prescription "Shenfu Tang" and is mainly derived from extracts of both traditional Chinese medicine red ginseng and prepared lateral root of monkshood with polysorbate 80 as auxiliary material. Shenfu injection may be administered through intramuscular injection, intravenous drip or intravenous injection. It produces good effects in restoring Yang and rescuing patients from collapse, tonifying Qi and preventing exhaustion. It is mainly used to treat not only syncope and prostration resulting from sudden Yang collapse (infectious, hemorrhagic and water depletion shock etc), but also pavor, palpitation, dyspnea with cough, stomachache, diarrhea and arthralgia etc caused by deficiency of Yang (deficiency of vital energy). Research group has audited the monitored hospitals and has carried out postmarketing study of Shenfu solution from many aspects including literature review, spontaneous reporting system (SRS) and hospital information system (HIS) data analysis etc. A summary is shown below.

Suppression of cellular apoptosis susceptibility (CSE1L) inhibits proliferation and induces apoptosis in colorectal cancer cells

The cellular apoptosis susceptibility (CSE1L) gene has been demonstrated to regulate multiple cellular mechanisms including the mitotic spindle check point as well as proliferation and apoptosis. However, the importance of CSE1L in human colon cancer is largely unknown. In the present study, we examined expression levels of CSE1L mRNA by semiquantitative RT-PCR. A lentivirus-mediated small interfering RNA (siRNA) was used to knock down CSE1L expression in the human colon cancer cell line RKO. Changes in CSE1L target gene expression were determined by RT-PCR. Cell proliferation was examined by a high content screening assay. In vitro tumorigenesis was measured by colony-formation assay. Cell cycle distribution and apoptosis were detected by flow cytometric analysis. We found CSE1L mRNA to be expressed in human colon cancer cells. Using a lentivirus based RNAi approach, CSE1L expression was significantly inhibited in RKO cells, causing cell cycle arrest in the G2/M and S phases and a delay in cell proliferation, as well as induction of apoptosis and an inhibition of colony growth capacity. Collectively, the results suggest that silencing of CSE1L may be a potential therapeutic approach for colon cancer.

Expert consensus for postmarketing Chinese medicine intensive hospital safety monitoring

It is of vital significance to conduct active postmarketing surveillance of Chinese medicine, as an active response to laws, rules and guidelines issued by the China Food and Drug Administration. These will provide technological support in evaluating adverse drug reactions (ADRs) or adverse drug events (ADEs). The expert consensus for postmarketing surveillance focuses on two surveillance designs; one is a large sample registry study to explore general population ADR/ADE characteristics, the other is a nested case-control study to explore the characteristic and mechanisms of ADRs.

Tuning topological edge states of Bi(111) bilayer film by edge adsorption

Based on first-principles and tight-binding calculations, we report that the topological edge states of zigzag Bi(111) nanoribbon can be significantly tuned by H edge adsorption. The Fermi velocity is increased by 1 order of magnitude, as the Dirac point is moved from the Brillouin zone boundary to the Brillouin zone center, and the real-space distribution of Dirac states are made twice more delocalized. These intriguing changes are explained by an orbital filtering effect of edge H atoms, which pushes certain components of the p orbital of edge Bi atoms out of the band gap regime that reshapes the topological edge states. In addition, the spin texture of the Dirac states is also modified, which is described by introducing an effective Hamiltonian. Our findings not only are of fundamental interest but also have practical implications in potential applications of topological insulators.

Aspirin-triggered Lipoxin A4 attenuates mechanical allodynia in association with inhibiting spinal JAK2/STAT3 signaling in neuropathic pain in rats

Aspirin-triggered Lipoxin A4 (ATL), as a Lipoxin A4 (LXA4) epimer, is endogenously produced by aspirin-acetylated cycloxygenase-2 (COX-2) and plays a vital role in endogenous anti-inflammation via the LXA4 receptor (ALX). Recent investigations have indicated that spinal neuroinflammation and the activation of the Janus Kinase 2 (JAK2)/Signal Transducers and Transcription Activators 3 (STAT3) signaling pathway are involved in neuropathic pain states. However, the effect of ATL on neuroinflammation and JAK2/STAT3 signaling in chronic constriction injury (CCI)-induced neuropathic pain in rats has not been well-studied. The present study demonstrated the anti-inflammatory and analgesic effect of ATL on neuropathic pain and assessed the role of spinal JAK2/STAT3 signaling on the effect of ATL. Intrathecal administration of ATL significantly attenuated mechanical allodynia via spinal ALX and inhibited the upregulation of pro-inflammatory cytokines (IL-1β, IL-6, and TNF-α) on day 7 of CCI surgery. In addition, ATL markedly suppressed the upregulation of p-STAT3 induced by the neuropathic pain. Blockade of JAK2-STAT3 signaling with intrathecal administration of the JAK2 inhibitor AG490 or the STAT3 inhibitor S3I-201 clearly reduced mechanical allodynia and the upregulation of pro-inflammatory cytokines in CCI rats. Interestingly, inhibition of JAK2/STAT3 signaling via ATL or the specific signaling inhibitor (AG49, S3I-201) further promoted the increased expression of suppressor of cytokine signaling 3 (SOCS3) mRNA in the spinal cord induced by CCI surgery. Taken together, our results suggested that the analgesic effect of ATL was mediated by inhibiting spinal JAK2/STAT3 signaling and hence the spinal neuroinflammation in CCI rats.

Antitumor effects of artesunate on human breast carcinoma MCF-7 cells and IGF-IR expression in nude mice xenografts

PURPOSE

The objective of this study was to investigate the anti-tumor effects and analyze the mechanism of artesunate (ART) action on breast cancer in vivo using tumor transplanted nude mice.

METHODS

The human breast tumor cell line MCF-7 was transplanted into nude mice, and the animals were treated with various doses of ART alone or in combination with cyclophosphamide (CTX) or normal saline (NS). The tumor inhibitory effects were observed and compared, and the ultrastructural morphology of the transplanted tumor cells was observed by electron microscopy. The apoptosis rates and cell cycle status were detected by flow cytometry (FCM). The expression of apoptosis-related proteins p53, Bcl-2, Bax and Caspase-3 were detected by immunohistochemistry and IGF-IR was detected by western blot. The expression correlation for these proteins was also analyzed.

RESULTS

The tumor inhibition rates in the low dose ART group, high dose ART group, CTX group and combined drug therapy group were (24.39±10.20)%, (40.24±7.02)%, (57.01±5.84)% and (68.29±5.1)%, respectively. The cell cycle was arrested in phase G0/G1 after treatment with ART. The expression of Bcl-2 was significantly reduced, and the expression levels of Bax and Caspase-3 were significantly increased in the ART group compared to the negative control saline group. There was no significant difference detected in p53 expression. The Bcl-2 level was negatively related to Bax and Caspase-3. The western blotting results showed IGF-IR downregulation.

CONCLUSIONS

ART inhibits the growth of MCF-7 breast tumor cell xenografts in nude mice. The anti-tumor mechanism of ART for human breast carcinoma in nude mice might be correlated with the alteration of apoptosis related protein expression, which may further induce apoptosis and inhibit cell proliferation.

Wet deposition of acidifying substances in different regions of China and the rest of East Asia: modeling with updated NAQPMS

The traditional way to study Sources-Receptor Relationships (SRRs) of wet deposition is based on sensitivity simulation, which has weakness in dealing with the non-linear secondary formation pollutants (e.g. ozone and nitrate). An on-line source tracking method has been developed in the Nested Air Quality Prediction Modeling System (NAQPMS) coupled with cloud-process module for the first time. The new model can not only quantify the total volume of the sulfate, nitrate and ammonium wet deposition with more accuracy, but also trace these acidic species to their emitted precursors. Compared with previous studies, our result clearly shows: (1) East China and Central China, which are the two primary export regions, have 15-30% and 10% effect on wet deposition in other areas, respectively; (2) Besides the above two regions, the total acid deposition in Southwestern and Northeastern China have reached or exceeded the critical loads under their own environmental conditions.

Guideline for postmarketing Chinese medicine pharmacoeconomic evaluation

Pharmacoeconomics is an important part of the postmarketing Chinese medicine (CM) evaluation, and postmarketing pharmacoeconomic evaluation can reveal the clinical and market value of CM. The purpose of establishing the guideline for pharmacoeconomic evaluation is to make the evaluation process and results regarding Chinese patent medicines both scientific and fair. Every country's guidelines for pharmacoeconomic evaluation act as reference guidelines, we have already drawn up the guideline that takes into account the special characteristics of CM; and these are in preparation for the postmarketing CM pharmacoeconomic evaluation.

Sirtuin 1 facilitates chemoresistance of pancreatic cancer cells by regulating adaptive response to chemotherapy-induced stress

Chemotherapy drugs themselves may act as stressors to induce adaptive responses to promote the chemoresistance of cancer cells. Our previous research showed that sirtuin 1 (SIRT1) was overexpressed in pancreatic cancer patients and deregulation of SIRT1 with RNAi could enhance chemosensitivity. Thus, we hypothesized that SIRT1 might facilitate chemoresistance in pancreatic cancer cells through regulating the adaptive response to chemotherapy-induced stress. In the present study, SIRT1 in PANC-1, BXPC-3, and ASPC-1 cells was upregulated after treatment with gemcitabine. Moreover, the decrease in SIRT1 activity with special inhibitor EX527 had a synergic effect on chemotherapy with gemcitabine in PANC-1 and ASPC-1 cell lines, which significantly promoted apoptosis, senescence, and G0 /G1 cycle arrest. Western blot results also showed that SIRT1, acetylated-p53, FOXO3a, and p21 were upregulated after combined treatment, whereas no obvious change was evident in total p53 protein. To further confirm the role of SIRT1 in clinical chemotherapy, SIRT1 was detected in eight pancreatic cancer tissues acquired by endoscopy ultrasonography guided fine needle aspiration biopsy before and after chemotherapy. Compared to before chemotherapy, SIRT1 was significantly increased after treatment with gemcitabine in six cases. Thus, our results indicated a special role for SIRT1 in the regulation of adaptive response to chemotherapy-induced stress, which is involved in chemoresistance. Moreover, it indicates that blocking SIRT1 activity with targeting drugs might be a novel strategy to reverse the chemoresistance of pancreatic cancer.

Using Bayesian optimization method and FLEXPART tracer model to evaluate CO emission in East China in springtime

Carbon monoxide (CO) is of great interest as a restriction factor for pollutants related to incomplete combustions. This study attempted to evaluate CO emission in East China using the analytical Bayesian inverse method and observations at Mount Hua in springtime. The mixing ratio of CO at the receptor was calculated using 5-day source-receptor relationship (SRR) simulated by a Lagrangian Particle Dispersion Model (FLEXPART) and CO emission flux. The stability of the inversion solution was evaluated on the basis of repeated random sampling simulations. The inversion results demonstrated that there were two city cluster regions (the Beijing-Tianjin-Hebei region and the low reaches of the Yangtze River Delta) where the difference between a priori (Intercontinental Chemical Transport Experiment-Phase B, INTEX-B) and a posteriori was statistically significant and the a priori might underestimate the CO emission flux by 37 %. A correction factor (a posteriori/a priori) of 1.26 was suggested for CO emission in China in spring. The spatial distribution and magnitude of the CO emission flux were comparable to the latest regional emission inventory in Asia (REAS2.0). Nevertheless, further evaluation is still necessary in view of the larger uncertainties for both the analytical inversion and the bottom-up statistical approaches.

Effects of Sirtinol on proliferation and 5-FU chemosensitivity of pancreatic cancer PANC-1 cells

AIM: To investigate the effects of SIRT1 specific inhibitor Sirtinol on proliferation and 5-FU chemosensitivity of pancreatic cancer PANC-1 cells.

METHODS: PANC-1 cells were treated with 25, 50 and 100 μmol/L Sirtinol for 48 h. The expression levels of SIRT1 were measured by Western blot. Cell proliferation was detected by MTT assay. Cell apoptosis was detected by flow cytometry (FCM). 5-FU chemosensitivity was measured by MTT assay.

RESULTS: Sirtinol obviously decreased the expression of SIRT1, inhibited cell proliferation and induced cell apoptosis in a dose-dependent manner. Moreover, compared with Sirtinol alone (A = 0.546 ± 0.020) or 5-FU alone (A = 0.526 ± 0.023), Sirtinol combined with 5-FU more significantly inhibited the proliferation of PANC-1 cells (A = 0.251 ± 0.017, both P < 0.01).

CONCLUSION: Sirtinol could induce cell proliferation inhibition and apoptosis, and enhance anti-cancer effects of chemotherapy on PANC-1 cells possibly via mechanisms associated with down-regulating SIRT1 expression.

Coupled Dirac fermions and neutrino-like oscillations in twisted bilayer graphene

The low-energy quasiparticles in graphene can be described by a Dirac-Weyl Hamiltonian for massless fermions, hence graphene has been proposed to be an effective medium to study exotic phenomena originally predicted for relativistic particle physics, such as Klein tunneling and Zitterbewegung. In this work, we show that another important particle-physics phenomenon, the neutrino oscillation, can be studied and observed in a particular graphene system, namely, twisted bilayer graphene. It has been found that graphene layers grown epitaxially on SiC or by the chemical vapor deposition method on metal substrates display a stacking pattern with adjacent layers rotated by an angle with respect to each other. The quasiparticle states in two distinct graphene layers act as neutrinos with two flavors, and the interlayer interaction between them induces an appreciable coupling between these two "flavors" of massless fermions, leading to neutrino-like oscillations. In addition, our calculation shows that anisotropic transport properties manifest in a specific energy window, which is accessible experimentally in twisted bilayer graphene. Combining two graphene layers enables us to probe the rich physics involving multiple interacting Dirac fermions.

[Research on early warning signals of adverse drug reactions to parenterally administered xiyanping based on spontaneous reporting system (SRS) data]

This article focused on early warning signals regarding the safety of parenterally administered Xiyanping. The study data was obtained from reports made between 2005-2012 from the national spontaneous reporting system (SRS). Proportion reporting ratio (PRR) and Bayesian confidence propagation neural network (BCPNN) algorithms were used to analyse: erythra, pruritus, anaphylactoid reactions and shiver with cold, these 4 adverse drug reactions had a total count of more than 500 events. The article found that Xiyanping's incidence rate of erythra was higher than for background-drugs in every year and in every season. Pruritus was an early warning signal in the second season of 2009, and anaphylactoid reaction was an early warning signal in the fourth season of 2011 and in the second season of 2012. There was however no early warning signal indicated by shiver with cold. This data indicates that erythra maybe an adverse drug reactions to parenterally administered Xiyanping, and if the incidence rate of pruritus and anaphylactoid reaction rises attention should be paid to its safety.

[Technical specifications for intensive hospital safety monitoring of post-marketing Chinese medicine (draft version for comments)]

It is of vital significance to conduct active post-marketing surveillance of Chinese medicine, as an active response to laws, rules and guidelines issued by the China food and drug administration. The standards for technological specifications based on expert consensus have been drafted. These will provide technological support in evaluating adverse drug reactions (ADRs) or adverse drug events (ADEs). The technological specifications for post-marketing surveillance focus on two surveillance designs; one is a large sample registry study to explore general population ADR/ADE characteristics, the other is a nested case-control study to explore the characteristic and mechanisms of ADRs.

[Real-world study of effect on liver function of parenterally administered shuxuetong with different doses]

OBJECTIVE

To analyze the effect on liver function of parenterally administered Shuxuetong Injection with different doses.

METHOD

The study is based on hospital information system (HIS) data. We group the cases by dose: The observation group receive a dose > 6 mL (recommended daily dose), the matched group receive the recommended dose. Chi-square test, logistic regression, logistic regression with propensity score, logistic regression with GBM propensity score were used to find the between group differences in ALT and AST after using parentyerally administered Shuxuetong injection.

RESULT

All tests show that there were no significant differences between groups in AST or ALT after we control for confounding factors.

CONCLUSION

Based on HIS data, there was no evidence to associate the use of Shuxuetong over the recommended dose and effects on liver function.

[Adverse drug reactions case reports for parenterally administered shuxuening based on analysis of literature]

Parenterally administered Shuxuening had made important contributions in the treatment of ischemic cardiovascular and cerebrovascular diseases since its use in 1995. Parenterally administered Shuxuening is widely used in clinical practice hence concern over its safety has gradually arisen. Based on published adverse drug reaction (ADR) case reports, this article analyzes cpatient characteristics and other data including: gender, age, history of allergies, primary disease, dose, treatment course, solvent, ADR occurrence and time scales. This will provide a clinical reference regarding ADRs to parenterally administered Shuxuening and influencing factors on their occurrence. Analysis showed that ADRs clinical symptoms include systemic damage, with damage to the skin, mucous membranes and respiratory system most common. ADRs occurred earliest after 1 minute of infusion, and after the 11th day at the latest. 70% cases of ADR occurred within 1 hour, therefore rapid occurrence is a primary clinical characteristic. The medication was largely used in accordance with the drug manual, and of the association of ADRs with allergies or different drug combination was not high. The occurrence of ADRs may not be entirely associated with the drug but the solvent used in its manufacture may be an important factor.