Biomimetic Total Synthesis of Clavicipitic Acid: A DDQ-Mediated Intramolecular Cross-Dehydrogenative Coupling Approach.

Clavicipitic acid, a communesin alkaloid precursor, has attracted significant attention due to its unique azepino[5,4,3-cd]indole framework. Herein, we report a novel biomimetic synthesis of clavicipitic acid diastereomers by utilizing a DDQ-mediated cross-dehydrogenative coupling (CDC) reaction. The synthesis involves Suzuki coupling for the prenylation of a 4-bromotryptophan derivative, followed by an intramolecular CDC reaction to construct the azepinoindole core. The trans isomer was obtained as the major product, and the two diastereomers were separable. The CDC reaction conditions, including temperature, solvent, and protecting groups, were investigated, and a plausible mechanism for the observed diastereoselectivity was proposed.

Rationally designed Mn2O3@ZnMn2O4/C core-shell hollow microspheres for aqueous zinc-ion batteries.

Manganese-based oxides are common cathode materials for aqueous zinc ion batteries (AZIBs) because of their great capacity and high working voltage. However, the sharp decline of capacity caused by the dissolution of manganese-based cathode materials and the low-rate performance restrict their development. To address these problems, unique core-shell structured Mn2O3@ZnMn2O4/C hollow microspheres are reported as an ideal cathode material for AZIBs. Benefiting from the hollow structure, the zeolitic imidazolate framework (ZIF)-derived carbon and ZnMn2O4. Its application in AZIBs as the cathode demonstrates its satisfactory rate performance, high cycle stability, and excellent reversibility. Its high reversible capacity is remarkable, which reaches its maximum of 289.9 mA h g-1 at 200 mA g-1 and maintains a capacity of 203.5 mA h g-1 after cycling for 700 times at 1000 mA g-1. These excellent performances indicate that this material is a potential cathode material of AZIBs.

[Identification of important biodiversity areas by InVEST model considering opographic relief: A case study of Yunnan Province, China]. / 顾及地形起伏的InVESTæ¨¡åž‹çš„ç”Ÿç‰©å¤šæ ·æ€§é‡è¦åŒºè¯†åˆ«­­ä»¥äº‘南省为例.

Accurately identifying important areas of biodiversity is one of the key issues in ecology and biodiversity research, as well as an important basis for the delineation of the red line for ecologi-cal protection and territorial spatial planning. With China's typical plateau mountainous area (Yunnan Province) as a research case, we used the net primary productivity (NPP) quantitative index method, InVEST model and InVEST model focusing on topographic relief to identify biodiversity important areas. The results showed that NPP quantitative index method was not suitable for the plateau mountainous areas with obvious vertical zonal development. The identified area contained only 26.1% of the protected areas. The InVEST model had higher identification accuracy than the NPP quantitative index method in Yunnan Province. The identified area covered 49.4% of the protected natural areas. Fragmentation was obvious in northwest Yunnan. The InVEST model focusing on topographic relief improved the identification accuracy of important areas of biodiversity, including 71.7% of nature reserves. The deficiency of NPP quantitative index method in water area identification was made up and the fragmentation problem of InVEST model was solved. The area of biodiversity important areas was 119466.94 km2, accounting for 30.3% of the total land area of Yunnan Province. The spatial distribution showed a pattern of "three barriers, two zones and one region for multi-point development".

Peripherally inserted central catheter placement in neonates with persistent left superior vena cava: Report of eight cases.

BACKGROUND: Reports on peripherally inserted central catheter (PICC) placement in neonates with persistent left superior vena cava (PLSVC) are rare. The majority of PLSVC patients have no clinical symptoms or hemodynamic changes, which are usually detected during cardiac catheterization, cardiac pacemaker implantation, or PICC placement. However, in neonates with PLSVC, PICC placement can be challenging. Here, we report PICC placement in eight neonates with PLSVC. CASE SUMMARY: This article introduces the concept of the "TIMB" bundle. After PICC implantation, we found PLSVC in all eight patients. The key points of care regarding PICC placement in neonates with PLSVC included "TIMB", where "T" indicates a reasonable choice of the catheterization time, "I" refers to a retrospective analysis of imaging data before catheterization, "M" refers to correct measurement of the body surface length, and "B" indicates that the tip of the PICC is placed in the middle and lower 1/3 of the left superior vena cava under the guidance of B-ultrasound. CONCLUSION: "TIMB" is a bundle for PICC placement in neonates, especially for those with PLSVC. Using this new approach can improve the first-attempt success rate of PICC placement, reveal cardiovascular abnormalities in advance, allow the selection of different measurement methods reasonably according to the puncture site, and finally, improve the accuracy of catheter positioning through the use of B-ultrasound guidance.

Neonatal necrotizing enterocolitis caused by umbilical arterial catheter-associated abdominal aortic embolism: A case report.

BACKGROUND: Reports of necrotizing enterocolitis (NEC) caused by umbilical arterial catheter (UAC)-associated abdominal aortic embolism in neonates are rare. Herein, we report the case of an extremely low birth weight (ELBW) infant with NEC caused by UAC-associated abdominal aortic embolism. CASE SUMMARY: A female infant, aged 21 min and weighing 830 g at 28+6 wk of gestational age, was referred to our hospital because of premature birth and shallow breathing. The patient was diagnosed with ELBW, neonatal respiratory distress syndrome, neonatal intrauterine infection, and neonatal asphyxia. Umbilical arterial and venous catheters were inserted on the day after birth and were removed 9 d later, according to the doctor's plan. Within 48 h after extubation, the patient's manifestations included poor responsiveness, heart rate range of 175-185/min, and currant jelly stool. Therefore, we considered a diagnosis of NEC. To determine the cause, we used B-mode ultrasound, which revealed a partial abdominal aortic embolism (2 cm × 0.3 cm) and abdominal effusion. The patient was treated with nil per os, gastrointestinal decompression, anti-infective therapy, blood transfusion, and low-molecular-weight heparin sodium q12h for anticoagulant therapy (from May 20 to June 1, the dosage of low-molecular-weight heparin sodium was adjusted according to the anti-Xa activity during treatment). On the 67th day after admission, the patient fully recovered and was discharged. CONCLUSION: The abdominal aortic thrombosis in this patient was considered to be catheter related, which requires immediate treatment once diagnosed. The choice of treatment should be determined according to the location of the thrombus and the patient's condition.

Intragenic heterochromatin-mediated alternative polyadenylation modulates miRNA and pollen development in rice.

Despite a much higher proportion of intragenic heterochromatin-containing genes in crop genomes, the importance of intragenic heterochromatin in crop development remains unclear. Intragenic heterochromatin can be recognised by a protein complex, ASI1-AIPP1-EDM2 (AAE) complex, to regulate alternative polyadenylation. Here, we investigated the impact of rice ASI1 on global poly(A) site usage through poly(A) sequencing and ASI1-dependent regulation on rice development. We found that OsASI1 is essential for rice pollen development and flowering. OsASI1 dysfunction has an important impact on global poly(A) site usage, which is closely related to heterochromatin marks. Intriguingly, OsASI1 interacts with the intronic heterochromatin of OsXRNL, a nuclear XRN family exonuclease gene involved in the processing of an miRNA precursor, to promote the processing of full-length OsXRNL and regulate miRNA abundance. We found that OsASI1-mediated regulation of pollen development partially depends on OsXRNL. Finally, we characterised the rice AAE complex and its involvement in alternative polyadenylation and pollen development. Our findings help to elucidate an epigenetic mechanism governing miRNA abundance and rice development, and provide a valuable resource for studying the epigenetic mechanisms of many important processes in crops.

"AFGP" bundles for an extremely preterm infant who underwent difficult removal of a peripherally inserted central catheter: A case report.

BACKGROUND: There have been few reports on level 3 difficult removal of peripherally inserted central catheter (PICC) in neonates. Here, we reported a case of an extremely preterm infant who underwent level 3 difficult removal of a PICC. CASE SUMMARY: Female baby A, weighing 1070 g at 27+1 wk of gestational age, was diagnosed with extremely preterm infant and neonatal respiratory distress syndrome. She underwent PICC insertion twice. The first PICC insertion went well; the second PICC was inserted in the right lower extremity, however, phlebitis occurred on the second day after the placement. On the third day of catheterization, phlebitis was aggravated, while the right leg circumference increased by 2.5 cm. On the fourth day of catheterization, more red swelling was found in the popliteal part, covering an area of about 1.5 cm × 4 cm, which was diagnosed as phlebitis level 3; thus, we decided to remove the PICC. During tube removal, the catheter rebounded and could not be pulled out (several conventional methods were performed). Finally, we successfully removed the PICC using a new approach termed "AFGP". On the 36th day of admission, the baby fully recovered and was discharged. CONCLUSION: The "AFGP" bundle approach was effective for an extremely preterm infant, who underwent level 3 difficult removal of a PICC.

[Monitoring and evaluation of eco-environmental quality of lake basin regions in Central Yunnan Province, China]. / 滇中湖泊流域生态环境质量监测与评价.

The basin region of nine highland lakes plays an important role in the economic development of Yunnan Province, in which, the basin region of the five lakes (Dianchi, Fuxianhu, Xingyunhu, Qiluhu and Yangzonghai Lake, hereinafter was called Five-lake Basin) locating in the central region of Yunnan Province is the most active economic and social development area of industry, agriculture and tourism, closely related to the eco-environmental quality of the whole basin. In this study, the eco-environmental quality of the Five-lake Basin from 1988 to 2018 was monitored and evaluated based on remote sensing ecological index (RSEI). The results showed that although the eco-environmental quality in this area had a trend of turning better from 1988 to 2018, with the mean value of RSEI increasing from 0.368 to 0.481, whereas the overall eco-environmental quality of the basin was poor. The area with improved eco-environmental quality accounted for 57.6%, which was mainly distributed in the mountains between lakes, while the declining area was mainly the flat area around the lake. The eco-environmental quality of Dianchi Lake, Fuxianhu Lake, and Yangzonghai Lake was improved during the study period, but the eco-environmental quality of Qiluhu Lake and Xingyunhu Lake deteriorated obviously in the last 10 years. The change of eco-environmental quality in each lake was consistent with the change of water quality. In the future, the improvement of eco-environmental quality needs more social attention and government investment.

Effect of 405 nm low intensity irradiation on the absorption spectrum of in-vitro hyperlipidemia blood.

BACKGROUND: Laser therapy is reported to be clinically effective for improving microcirculation, rheological properties and blood lipid profiles despite the lack of certainty on the mechanism. OBJECTIVE: This study intends to provide methods to drop blood lipid level of hyperlipidemia samples by low-intensity laser irradiation therapy and provide reasoning of mechanism. METHODS: Twenty whole blood samples of high level of lipids profile are irradiated by 405 nm low-intensity laser at 12 J/cm2 twice a day for 3 days and compared with normal lipids profile group. Then whole blood sample are centrifuged to obtain result of erythrocyte for further interpretation. Multi-scan spectrum microplate reader is used to measure absorption spectrum and data is analyzed by software SPSS 14.0. RESULTS: Results show that after 405 nm low-intensity laser irradiation, whole blood samples of high lipid level statistically have higher absorbance peak value than normal samples while erythrocyte samples have lower absorbance peak value. CONCLUSIONS: From the divergence of absorption peak value change after low-intensity laser irradiation for whole blood sample and erythrocyte, we suspect that low level laser irradiation affects the enzymes activity of lipid metabolism, improves the cholesterol balance of plasma and cytoplasm in erythrocyte, and decreases aggregation of the erythrocyte.

Finite element method simulating temperature distribution in skin induced by 980-nm pulsed laser based on pain stimulation.

For predicting the temperature distribution within skin tissue in 980-nm laser-evoked potentials (LEPs) experiments, a five-layer finite element model (FEM-5) was constructed based on Pennes bio-heat conduction equation and the Lambert-Beer law. The prediction results of the FEM-5 model were verified by ex vivo pig skin and in vivo rat experiments. Thirty ex vivo pig skin samples were used to verify the temperature distribution predicted by the model. The output energy of the laser was 1.8, 3, and 4.4 J. The laser spot radius was 1 mm. The experiment time was 30 s. The laser stimulated the surface of the ex vivo pig skin beginning at 10 s and lasted for 40 ms. A thermocouple thermometer was used to measure the temperature of the surface and internal layers of the ex vivo pig skin, and the sampling frequency was set to 60 Hz. For the in vivo experiments, nine adult male Wistar rats weighing 180 ± 10 g were used to verify the prediction results of the model by tail-flick latency. The output energy of the laser was 1.4 and 2.08 J. The pulsed width was 40 ms. The laser spot radius was 1 mm. The Pearson product-moment correlation and Kruskal-Wallis test were used to analyze the correlation and the difference of data. The results of all experiments showed that the measured and predicted data had no significant difference (P > 0.05) and good correlation (r > 0.9). The safe laser output energy range (1.8-3 J) was also predicted. Using the FEM-5 model prediction, the effective pain depth could be accurately controlled, and the nociceptors could be selectively activated. The FEM-5 model can be extended to guide experimental research and clinical applications for humans.

Hypocrol A, a new tyrosol derivative from a sponge-derived strain of the fungus Hypocrea koningii.

In continuation of our search for new antibacterial and antioxidant metabolites from sponge-derived fungi, one new tyrosol derivative, hypocrol A (1), together with four known congeners, trichodenol B (2), 4-hydroxyphenethyl acetate (3), 4-hydroxyphenethyl tetradecanoate (4) and 1-oleyltyrosol (5), was isolated from the strain Hypocrea koningii PF04. Their planar structures were unequivocally elucidated by spectroscopic methods and comparison with the literature data. All the compounds displayed weak antibacterial activities against Staphylococcus aureus, methicillin-resistant S. aureus and Escherichia coli, whereas compounds 1 and 2 exhibited a moderate antioxidant efficacy in the DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging assay with IC50 values of 48.5 and 97.4 µg/mL, respectively.

New Furan and Cyclopentenone Derivatives from the Sponge-Associated Fungus Hypocrea Koningii PF04.

Two new furan derivatives, hypofurans A and B (1 and 2), and three new cyclopentenone derivatives, hypocrenones A-C (3-5), along with seven known compounds (6-12), were isolated from a marine fungus Hypocrea koningii PF04 associated with the sponge Phakellia fusca. Among them, compounds 10 and 11 were obtained for the first time as natural products. The planar structures of compounds 1-5 were elucidated by analysis of their spectroscopic data. Meanwhile, the absolute configuration of 1 was determined as 2R,3R by the comparison of the experimental and calculated electronic circular dichroism (ECD) spectra. All the isolates were evaluated for their antibacterial and antioxidant activity. Compounds 1, 10, and 12 all showed modest antibacterial activity against Staphylococcus aureus ATCC25923 (MIC, 32 µg/mL). In addition, compounds 1, 10 and 11 exhibited moderate DPPH radical scavenging capacity with IC50 values of 27.4, 16.8, and 61.7 µg/mL, respectively.

Temporal and spatial temperature distributions on glabrous skin irradiated by a 1940 nm continuous-wave laser stimulator.

For predicting pain stimulation effects and avoiding damage in 1940nm laser evoked potentials (LEPs) experiments, a 2-layer finite element model (FEM-2) was constructed. A series of experiments were conducted on ex-vivo pig skin pieces to verify temperature distribution predicted by this model. Various laser powers and beam radii were employed. Experimental data of time-dependent temperature responses in different sub-skin depths and space-dependent surface temperature was recorded by thermocouple instrument. By comparing with the experimental data and model results, FEM-2 model was proved to predict temperature distributions accurately. A logarithmic relationship between laser power density and temperature increment was revealed by the results. It is concluded that power density is an effective parameter to estimate pain and damage effect. The obtained results also indicated that the proposed FEM-2 model can be extended to predict pain and damage thresholds of human skin samples and thus contribute to LEPs study.

Design, synthesis and anticancer activity of oxoaporphine alkaloid derivatives.

A series of new oxoaporphine derivatives were synthesized and their inhibitory activity of topoisomerase I, cytotoxicity and DNA-binding properties were studied. Oxoaporphine can strongly inhibit topoisomerase I at concentrations of 5-50 µM and the cytotoxicity of the derivatives are more potent than their lead compound. Hypochromism, broadening and red shift in the absorption spectra were observed when these compounds bind to calf thymus DNA (CT DNA). These spectral characteristics were consistent with the intercalative binding of these compounds.

Effect of low-level laser therapy on allergic asthma in rats.

Asthma is a complex chronic inflammatory disease of the airways that involves the activation of many inflammatory and other types of cells. We investigated the effect of low-level laser therapy (LLLT) on allergic asthma in rats and compared its effect with that of the glucocorticoid budesonide. Asthma was induced by challenge and repeated exposure to ovalbumin. Asthmatic rats were then treated with LLLT or budesonide suspension. LLLT at 8 J/cm(2) once daily for 21 days could relieve pathological damage and airway inflammation in asthmatic rats. LLLT could decrease the total numbers of cells and eosinophils in bronchoalveolar lavage fluid. LLLT could reduce levels of IL-4 and increase IFN-γ levels in bronchoalveolar lavage fluid and serum, meanwhile reduce serum IgE levels. Flow cytometry assay showed that LLLT can regulate the Th1/Th2 imbalance of asthmatic rats. LLLT had a similar effect to that of budesonide. These findings suggest that the mechanism of LLLT treatment of asthma is by adjustment of Th1/Th2 imbalance. Thus, LLLT could take over some of the effects of budesonide for the treatment of asthma, thereby reducing some of the side effects of budesonide.

A new phenylethanoid glycoside with antioxidant and anti-HBV activity from Tarphochlamys affinis.

A new phenylethanoid glycoside, named taraffinisoside A (1), together with five known glycosides were isolated from the stems and leaves of Tarphochlamys affinis. The structure of taraffinisoside A was identified on the basis of detailed spectral analysis. Compounds 1-4 and 6 showed potent antioxidant activities with IC50 values of 10.36, 19.73, 43.95, 15.30 and 46.04 µM by 1,1-diphenyl-2-picryhydrazyl radical-scavenging assay. Compounds 1, 2 and 4 showed anti-HBV activities, with IC50 values of 0.50, 0.72 and 0.26 mM for HBsAg and 0.93, 0.42 and 0.07 mM for HBeAg, respectively.

[The noninvasive measurement research of human blood parameters under flow control of time gate].

In order to further improve the noninvasive measurement precision of human blood components and achieve clinical requirements, we propose a new measurement method based on the dynamic dual wavelength time-resolved transmittance measurement, combined with the advanced time gate technology and Laplasse transform to detect human blood components noninvasively in the blocked blood flow conditions. Simulation results show that when p>0, emphasizing the importance of early arriving photons contribution can enhance the detection sensitivity of human body blood parameters.

Semi-supervised clustering algorithm for haplotype assembly problem based on MEC model.

Haplotype assembly is to infer a pair of haplotypes from localized polymorphism data. In this paper, a semi-supervised clustering algorithm-SSK (semi-supervised K-means) is proposed for it, which, to our knowledge, is the first semi-supervised clustering method for it. In SSK, some positive information is firstly extracted. The information is then used to help k-means to cluster all SNP fragments into two sets from which two haplotypes can be reconstructed. The performance of SSK is tested on both real data and simulated data. The results show that it outperforms several state-of-the-art algorithms on minimum error correction (MEC) model.

Drosophila gene expression pattern annotation through multi-instance multi-label learning.

In the studies of Drosophila embryogenesis, a large number of two-dimensional digital images of gene expression patterns have been produced to build an atlas of spatio-temporal gene expression dynamics across developmental time. Gene expressions captured in these images have been manually annotated with anatomical and developmental ontology terms using a controlled vocabulary (CV), which are useful in research aimed at understanding gene functions, interactions, and networks. With the rapid accumulation of images, the process of manual annotation has become increasingly cumbersome, and computational methods to automate this task are urgently needed. However, the automated annotation of embryo images is challenging. This is because the annotation terms spatially correspond to local expression patterns of images, yet they are assigned collectively to groups of images and it is unknown which term corresponds to which region of which image in the group. In this paper, we address this problem using a new machine learning framework, Multi-Instance Multi-Label (MIML) learning. We first show that the underlying nature of the annotation task is a typical MIML learning problem. Then, we propose two support vector machine algorithms under the MIML framework for the task. Experimental results on the FlyExpress database (a digital library of standardized Drosophila gene expression pattern images) reveal that the exploitation of MIML framework leads to significant performance improvement over state-of-the-art approaches.