Radical-Mediated Strategies for the Functionalization of Alkenes with Diazo Compounds.

One of the most common reactions of diazo compounds with alkenes is cyclopropanation, which occurs through metal carbene or free carbene intermediates. Alternative functionalization of alkenes with diazo compounds is limited, and a methodology for the addition of the elements of Z-CHR2 (with Z = H or heteroatom, and CHR2 originates from N2═CR2) across a carbon-carbon double bond has not been reported. Here we report a novel reaction of diazo compounds utilizing a radical-mediated addition strategy to achieve difunctionalization of diverse alkenes. Diazo compounds are transformed to carbon radicals with a photocatalyst or an iron catalyst through PCET processes. The carbon radical selectively adds to diverse alkenes, delivering new carbon radical species, and then forms products through hydroalkylation by thiol-assisted hydrogen atom transfer (HAT), or forms azidoalkylation products through an iron catalytic cycle. These two processes are highly complementary, proceed under mild reaction conditions, and show high functional group tolerance. Furthermore, both transformations are successfully performed on a gram-scale, and diverse γ-amino esters, γ-amino alcohols, and complex spirolactams are easily prepared with commercially available reagents. Mechanistic studies reveal the plausible pathways that link the two processes and explain the unique advantages of each.

[Application of quality by design in granulation process for ginkgo leaf tablet (⠣)： influence and control of raw materials' quality variation].

Raw materials' quality variation could affect the quality consistency of product and the clinical efficacy. In this paper, the high shear wet granulation (HSWG) process of the ginkgo leaf tablet was taken as the research object. Ginkgo biloba extracts and excipients microcrystalline cellulose collected from various sources and batches were used to simulate raw materials' quality variation. Real-time torque was recorded to analyze the viscosity of the wetting mass, and then by combining with physical fingerprint, the impact of physical quality variation of powders on granule properties could be investigated. Based on regime map thesis, whether the granules' nucleation mode was in mechanical dispersion regime was determined by calculating dimensionless parameters, which would lead to the unstable output in considerations of granule yield ratio and particle size distribution (PSD) curve. The orthogonal partial least square (OPLS) model was adopted to build the relationship between the micromeritic properties and the mediangranule size (D50) of Ginkgo biloba granules and then the critical material attributes (CMAs) were screened by variable importance in the projection (VIP) indexes. The results demonstrated that the properties of powders including hygroscopicity, angle of repose, Hausner ratio, Carr index, D10 and loss on drying affected the granule size. Besides, Ginkgo biloba granules were compressed into tablets. In view of tensile strength analysis, the raw materials' quality variation did not result in decrease of tensile strength of the ginkgo leaf tablets. The design space of critical quality attributes (CQAs) and the process design space which could cope with raw materials' quality variation were proved to be robust..

[Emission Characterstics of VOCs and n-alkanes from Diesel Forklifts].

Non-road diesel vehicle exhaust is an important emission source that affects air quality in China, yet knowledge regarding its chemical composition and potential influence factors remains limited. Six typical forklifts were selected to study the effect of diesel particulate filters (DPF) on the emission characteristics of volatile organic compounds (VOCs) and n-alkanes using online monitoring of gaseous components combined with offline analysis. The results showed that oxygenated volatile organic compounds (OVOCs), olefins, alkanes, aromatic hydrocarbons, and halogenated hydrocarbons accounted for 26%-37%, 16%-36%, 19%-22%, 13%-21%, and 4%-7% of the measured VOCs in forklift exhaust, respectively. The VOCs emission factors of low-power and high-power forklifts were(2.47±0.33)g·kg-1 and (1.48±0.24)g·kg-1, respectively. The forklift exhaust emission factors of total VOCs without and with DPF were(1.94±0.58)g·kg-1and (2.08±0.79)g·kg-1, respectively. Our results showed that DDF exerted minor impact on VOCs emission. However, it is worth noting that DPF can efficiently remove some types of OVOCs components. For example, the emission factors of acetaldehyde and acetone of the forklifts with DPF were reduced by 19% and 26%, respectively, compared to that of those without DPF. The carbon numbers of n-alkane fractions showed a bimodal distribution of C7-C17 and C24-C31, respectively, with C15 being the dominant peak carbon. The average emission factors of n-alkanes were (115±34) mg·kg-1 (without DPF) and (53.7±19)mg·kg-1 (with DPF), respectively, with a decrease of 53%, indicating that DPF can effectively reduce the emission of n-alkane in the exhaust of forklifts. Our results can provide scientific support for the precise control of non-road construction machinery exhaust emissions and the further improvement of regional air quality.

The Retrotransposition of L1 is Involved in the Reconsolidation of Contextual Fear Memory in Mice.

BACKGROUND: The long interspersed element-1 (L1) participates in memory formation, and DNA methylation patterns of L1 may suggest resilience or vulnerability factors for Post-Traumatic Stress Disorder (PTSD), of which the principal manifestation is a pathological exacerbation of fear memory. However, the unique roles of L1 in the reconsolidation of fear memory remain poorly understood. OBJECTIVE: The study aimed to investigate the role of L1 in the reconsolidation of context-dependent fear memory. METHODS: Mice underwent fear conditioning and fear recall in the observation chambers. Fear memory was assessed by calculating the percentage of time spent freezing in 5 min. The medial prefrontal cortex (mPFC) and hippocampus were removed for further analysis. Open Reading Frame 1 (ORF1) mRNA and ORF2 mRNA of L1 were analyzed by real-time quantitative polymerase chain reaction. After reactivation of fear memory, lamivudine was administered and its effects on fear memory reconsolidation were observed. RESULTS: ORF1 and ORF2 mRNA expressions in the mPFC and hippocampus after recent (24 h) and remote (14 days) fear memory recall exhibited augmentation via different temporal and spatial patterns. Reconsolidation of fear memory was markedly inhibited in mice treated with lamivudine, which could block L1. DNA methyltransferase mRNA expression declined following lamivudine treatment in remote fear memory recall. CONCLUSION: The retrotransposition of L1 participated in the reconsolidation of fear memory after reactivation of fear memory, and with lamivudine treatment, spontaneous recovery decreased with time after recent and remote fear memory recall, providing clues for understanding the roles of L1 in fear memory.

[Correlation of Blimp1 with ATF4/CHOP Signaling Pathway in Multiple Myeloma U266 Cells].

OBJECTIVE: To investigate whether Blimp1 plays an anti-apoptosis role in myeloma by interfering with ATF4/CHOP cell apoptosis pathway induced by endoplasmic reticulum stress, and to explore the anti-myeloma mechanism of aspirin. METHODS: The bone marrow fluid of 40 newly diagnosed multiple myeloma patients without treatment and 30 control people with relatively normal bone marrow was collected. Flow cytometry was used to separated the normal and abnormal plasma cells, LV-Blimp1-RNAi (40051-2) recombinant lentivirus down-regulates the expression of Blimp-1 in U266 cell line and detected the changes of the expression of ATF4 and CHOP gene. U266 cells were stimulated by aspirin at different concentrations (0, 0.5, 2.5, 5.0 mmol/L) in vitro. Then the effect of aspirin on proliferation of U266 cells was measured by CCK-8 assay, the mRNA expression levels of Blimp1, ATF4 and CHOP in four groups were detected by real-time PCR. RESULTS: The expression level of Blimp1 in phenotype abnormal plasma cells was significantly increased as compared with normal cells, while the expression of ATF4 and CHOP in phenotype abnormal plasma cells was significantly decreased as compared with normal cells (P＜0.05). In the case of MOI=100, the transfection efficiency of U266 cells was beyond 80% as detected by fluorescence microscopy. Compared with blank conrol and negatine control groups, Blimp1 mRNA expression level in positive group was significantly reduced while ATF4 and CHOP expression significantly increased. CCK-8 showed that the proliferation activity of U266 cells could be inhibited by aspirin, which showed a time-and dose-dependent manner; at the same time, the expression level of Blimp1 in U266 cells were decreased with the increasing of aspirin concentration, while the expression level of ATF4 and CHOP was increased with the increasing of aspirin concentration. CONCLUSIONS: Blimp1 may display the anti-apoptosis of myeloma cells through interfering with ATF4/CHOP signaling pathway; low dose of aspirin may play anti-myeloma effect by inhibiting the expression of Blimp1 in myeloma cells.

[Expression of Blimp1、ATF4 and CHOP in Multiple Myeloma Cells and Effect of Aspirin on Their Expression].

OBJECTIVE: To explore the expression of Blimp1, ATF4 and CHOP in bone marrow mononuclear cells from patients with multiple myeloma as well as the effect of aspirin on their expression. METHODS: Sixty untreated patients with multiple myeloma and 30 patients with relatively normal bone marrow were selected. Mononuclear cells from the bone marrow fluid were separated using Ficoll separation solution. CD138+ plasma cells were sorted by immunomagnetic beads method. RT-PCR was used to detect the expression levels of Blimp1, ATF4 and CHOP mRNA in U266 cells cultured in vitro. The cells were divided into blank control group, negative control group (no-loaded virus transfection) and positive experimental group [LV-Blimp1-RNAi (40051-2) transfection] by lentivirus transfection. RT-PCR was used to detect the expression of Blimp1, ATF4 and CHOP mRNA in cells of different groups. U266 cells were stimulated in vitro with different concentrations of aspirin solution (0, 0.5 mmol/L, 2.5 mmol/L, 5.0 mmol/L) for 24, 48 h and 72 h, respectively. The ability of cell proliferation in different groups was measured by CCK-8. U266 cells were stimulated with different concentrations of aspirin for 48 hours. And the mRNA expression of Blimp1, ATF4 and CHOP was detected by RT-PCR. RESULTS: Compared with plasma cells in normal group, the expression of Blimp1 mRNA in CD138+ plasma cells of MM patients significantly increased (8.040±1.878), and the mRNA expression levels of ATF4 and CHOP significantly decreased (0.735±0.089; 0.837±0.062) (P＜0.05). U266 cells were cultured in vitro. Compared with the blank control group and the negative control group, the mRNA expression level of Blimp in the positive experimental group was significantly down-regulated after infection with LV-Blimp1-RNAi (40051-2) lentiviral expression vector (0.637±0.021). ATF4 and CHOP mRNA expression levels were significantly increased (1.452 ± 0.027; 1.721 ± 0.038) (P＜0.05). The proliferation of U266 cells decreased after stimulation with aspirin. In the range of (0.5-5) mmol/L, aspirin could significantly inhibit the proliferation of U266 cells. The inhibition effect of aspirin was increased along with prolongation of time and increase of concentrations. After aspirin stimulation of different concentrations for 48 hours, the expression level of Blimp1 in U266 cells decreased with increasing of drug concentration, while the expression levels of ATF4 and CHOP increased with increasing of drug concentration. CONCLUSION: Inhibition of Blimp1 expression in multiple myeloma cells can promote the expression of ATF4 and CHOP. Aspirin can inhibit the proliferation activity of myeloma cells by down-regulating Blimp1 expression in myeloma cells and up-regulating ATF4 and CHOP expression, therefore plays an anti-tumor rote.

[Emission Characteristics of Light-Duty Gasoline Vehicle Exhaust Based on Acceleration Simulation Mode].

In this study, 127 light-duty gasoline cars and 10 light-duty gasoline trucks with different emission standards were selected to explore the influences of different conditions and vehicle parameters on the emission characteristics of carbon dioxide (CO2), carbon monoxide (CO), nitrogen oxides (NOx), hydrocarbons (HC), and methane (CH4) using a portable emission measurement system based on a chassis dynamometer under acceleration simulation mode. The results showed that the gaseous pollutants of light-duty gasoline vehicles displayed a relatively lower emission rate under the idle condition, which accounted for only 22.9% and 25.8% of the emission rate at the accelerated condition and constant speed condition, respectively. The pollutant emission characteristics were closely related to the working conditions. The emission rates of CO2 and NOx in the accelerated condition were less than those at the constant speed condition, while the emission rates of CO, HC, and CH4 in the accelerated condition were higher than those at the constant speed condition. In the constant low-speed condition, the emission factors of CO2, CO, NOx, HC, and CH4 were 383.20, 2.98, 1.60, 0.14, and 0.03 g·km-1 for light-duty gasoline cars, respectively, and 360.66, 2.64, 1.61, 0.0055, and 0.0027 g·km-1 for light-duty gasoline trucks, respectively. Tighter emission standards have caused significant reductions in emissions. The emission factors of CO, NOx, HC, and CH4 could be decreased by 87.5%, 97.3%, 97.9%, and 86.4%, respectively, from China Ⅰ to China Ⅴ. A non-linear relationship was found between the age, odometer, vehicle weight, and vehicular emissions. In addition, the engine displacement was positively correlated with vehicular emissions.

[Effect of Krüppel-like factor 4 overexpression on heat stress-induced apoptosis of Raw264.7 macrophages].

OBJECTIVE: To observe the effect of Krüppel-like factor 4 (KLF4) overexpression on heat stress-induced apoptosis of Raw264.7 macrophages. METHODS: The fragment containing full length mouse KLF4 cDNA coding sequence was inserted into the pcDNA3.1 vector and Raw264.7 macrophages were transfected with pcDNA3.1-KLF4 plasmids using lipofectamine.The expression of KLF4 was examined by Western blot in the Raw264.7 macrophages stably transfected with pcDNA3.1- KLF4 plasmids. Raw264.7 cells transfected with pcDNA3.1 and pcDNA3.1-KLF4 were exposed to heat stress (42 degrees C) for 1h and recovered at 37 degrees C for 12h. Flow cytometry, Hoechest 33258 staining assay, and DNA ladder assays were performed to assess the apoptosis. RESULTS: The KLF4 overexpressed Raw264.7 macrophages were established. After the heat stress, flow cytometry showed that apoptotic cells increased significantly in KLF4 overexpressed cells compared with the vector control; Hoechest 33258 staining was characterized with classical changes including apoptotic body, and nuclear condensation. Agarose gel electrophoresis showed that "DNA ladder" could be observed clearly. CONCLUSION: KLF4 overexpression can increase heat stress-induced apoptosis of Raw264.7 macrophages.

[Expression of Blimp-1 mRNA in Bone Marrow Mononuclear Cells in Multiple Myeloma Patients and Its Clinical Significance].

OBJECTIVE: To investigate the expression level of B lymphocyte-induced maturation protein-1(Blimp-1) mRNA in bone marrow mononuclear cells(BMMNC) of multiple myeloma(MM) patients and its clinical significance. METHODS: Fluorescent quantitative real-time PCR(qRT-PCR) was used to measure Blimp-1 mRNA expression in BMMNC and flow cytometry(FCM) was performed to detect the number of malignant plasma cells in bone marrow of MM group (39 newly-diagnosed and untreated patients) and IDA group (5 IDA patients). The clinical data of all the patients' were collected, and the 39 patients in MM group were divided into 2 subgroups: in BD group 20 cases were treated with bortezomib-based regimen and in VOD group 19 patients were treated with VAD regimen. The age, sex, clinseal stage and type between the 2 subgroups were not statistically different. Blimp-1 mRNA expression level in BMMNC of MM patients was detected by qRT-PCR after 3 treatment cycles. RESULTS: The expression levels of Blimp-1 mRNA in BMMNC of IDA patients and MM patients divided into 3 groups according to ISS were (0.00047±0.00027), ISS I(0.09543±0.02800), Ⅱ(0.13606±0.04162),Ⅲ (0.21202±0.03940), separately. There was statistical difference among the 4 groups(F=56.929,P<0.05) and there was significant difference between any 2 groups of these 4 groups(P<0.05). Significant positive correlation was found between Blimp-1 mRNA expression level and the number of malignant plasma cells, serum monoclonal proteins (M protein), ß2-microglobulin(ß2-MG), lactic dehydrogenase(LDH), C-reactive protein(CRP)(P<0.05). There was significant negative correlation between Blimp-1 mRNA and hemoglobin (Hb) level (P<0.05). After 3 cycles of chemotherapy, Blimp-1 mRNA level of patients with a >50% reduction of M protein was significantly lower than that of patients whose M protein did not decrease significantly(P<0.05). After 3 treatment cycles, Blimp-1 mRNA expression in BMMNC in BD group was significantly lower than that in VAD group [(0.02388±0.00871) vs (0.04823±0.00219), P<0.05]. CONCLUSION: The Blimp-1 mRNA expression level in BMMNC may reflect the tumor burden in MM patients, which related with ISS, and positively correlated with the malignant plasma cell number, M protein, ß2-MG, LDH, CRP level, and negatively correlated with Hb. The change of Blimp-1 mRNA expression level in BMMNC relates with the extent of M protein reduction, suggesting it may be used as a marker for response to therapy. Bortezomib may have effect on malignant plasma cells by suppressing Blimp-1 mRNA expression.

TPX2 siRNA regulates growth and invasion of esophageal cancer cells.

PURPOSE: Observe how specific small RNA interference (siRNA) aimed at TPX2 gene suppresses TPX2 gene expression in esophageal cancer EC9706 cells and the effect on esophageal cancer cell growth and invasion ability. METHODS: Transfect TPX2 siRNA into EC9706 cells via lipofectamin 2000. The experiments were divided into three groups, a negative control, a blank control and an siRNA interference group (24h, 48h, 72h, 96h). We examined RNA and protein level alteration of the TPX2 gene after TPX2 siRNA transfection by RT-PCR and Western blot analysis. Detection of how TPX2 siRNA influences EC9706 cell proliferation was done by MTT, cell apoptosis monitored through Tunel assay, in vitro invasion ability via Boyden chamber and cell cycle change by flow cytometry. RESULTS: After effective siRNA transfection, TPX2 mRNA and protein expression level in siRNA interference group were (0.31±0.08, 0.39±0.12),72h after transfection, significantly lower than blank control group (1.00±0.01) and negative control group (0.98±0.11), (F=71.182, t1=8.17, t2=7.90, P<0.05); MTT results demonstrated that cell growth and proliferation were inhibited and the inhibition rate was up to 35.4% (P<0.05) compared with the control group. TUNEL results indicated that cell apoptosis index in siRNA interference group was 18.28±0.35, higher than that in blank control group (4.07±0.26)and negative control group (4.13±0.22), (F=244.5, t1=60.61, t2=53.32, P<0.01). Boyden chamber results showed that the transmembrane cell number was 45.30±8.08 in siRNA interference group, less than blank control group (121.90±7.83), (F=122.46, t1=11.81, t2=10.47, P<0.01); besides, in siRNA interference group cell invasion inhibition rate was 71.42±9.12, higher than negative control group (5.65±3.55), (t=14.256, P<0.01). Flow cytometry results illustrated that more EC9706 cells went into apoptosis and cell cycle arrested in S phase. Similar results were obtained by in vivo transplantation, as TPX2 siRNA transfection significantly reduced tumor growth of the xenograft in nude mice. CONCLUSION: siRNA could effectively inhibit the invasion and metastasis of EC9706 cells, promote the apoptosis of tumor cells and may become a new approach for treatment of esophageal carcinoma.

[Characterization of polycyclic aromatic hydrocarbons contaminations in surface sediments from Zhalong wetland, China].

Soxhlet extraction, silica gel alumina column for separation and clean up and gas chromatography-mass spectrometer (GC-MS) for qualitative and quantitative analysis were used for study environmental behavior of 15 priority PAHs of twelve surface sediment samples collected from Zhalong wetland, Heilongjiang Province. The objectives of this study were to identify the PAHs contamination level, composition pattern, pollution sources and pathways, and to assess the ecological risk of PAHs to aquatic life in Zhalong wetland. The total concentrations of 15 priority PAHs ranged form 31.9 to 290 ng/g (dry weight), with a mean value of 130 ng/g. The PAHs profiles were dominated by two-to four-ring compounds which accounted for 90% of total PAHs. Phenanthrene, fluorine, fluoranthene, and pyrene represented the highest fractions in all surface sediment samples. Comparing with other results from wetlands and lakes in China or other countries, the PAH concentrations level in Zhalong wetland surface sediments were relatively low, in the same range of Lharu wetland. The linear regression analysis showed that the concentrations of PAHs were significantly correlated to the sediment total organic carbon (TOC) content (R2 = 0.87). PAHs contamination might mainly came from biomass and coal combustion. After long range atmospheric transport and deposition, the released PAHs finally accumulated into wetland sediment. Ecology risk assessment indicated that phenanthrene and fluorine had exhibited a tendency of accumulation on surface sediment of Zhalong wetland, which would exert negative toxic effect on aquatic organism.