Ligand-Controlled Cobalt-Catalyzed Regio-, Enantio-, and Diastereoselective Oxyheterocyclic Alkene Hydroalkylation.

Metal-hydride-catalyzed alkene hydroalkylation has been developed as an efficient method for C(sp3)-C(sp3) coupling with broad substrate availability and high functional group compatibility. However, auxiliary groups, a conjugated group or a chelation-directing group, are commonly required to attain high regio- and enantioselectivities. Herein, we reported a ligand-controlled cobalt-hydride-catalyzed regio-, enantio-, and diastereoselective oxyheterocyclic alkene hydroalkylation without chelation-directing groups. This reaction enables the hydroalkylation of conjugated and unconjugated oxyheterocyclic alkenes to deliver C2- or C3-alkylated tetrahydrofuran or tetrahydropyran in uniformly good yields and with high regio- and enantioselectivities. In addition, hydroalkylation of C2-substituted 2,5-dihydrofuran resulted in the simultaneous construction of 1,3-distereocenters, providing convenient access to polysubstituted tetrahydrofuran with multiple enantioenriched C(sp3) centers.

Effect of new simple breathing apparatus on oxygen therapy in patients with severe and critical coronavirus disease 2019 / 中华危重病急救医学

Objective:To make a new simple respirator and observe the oxygen therapy effect of the respirator on patients with severe and critical coronavirus disease 2019 (COVID-19).Methods:Based on the infectivity and hospital requirements of COVID-19, a new simple respirator was designed by the medical staff of the Department of Anesthesiology of the Second Affiliated Hospital of Nanchang University, which was applied on the 22 patients with severe and critical COVID-19 who needed oxygen therapy admitted to the Cancer Center of Tongji Medical College of Huazhong University of Science and Technology from February 15th to March 15th in 2020. The new simple respirator contained two National Utility Model Patents (a respirator: ZL 2015 2 0410623.6, a fluid switch and oxygen suction device: ZL 2017 2 0873509.6), which was mainly composed of anesthesia mask and filter, L-shaped connecting tube, soft breathing bladder, connecting tube and elastic fixing belt. When in use, the anesthesia mask was fixed to the patient's mouth and nose with elastic straps, the connecting tube was inserted into the oxygen meter interface, the oxygen flow was adjusted to 6-10 L/min, and the L-shaped connecting tube was opened immediately after the soft breathing bag was full. The carbon dioxide and excess oxygen in the body was discharged from exhaust port. The oxygen flow was lowered to 2-3 L/min, the patient's respiratory rate (RR) was observed through the soft breathing bag fluctuations, and the oxygen flow was adjusted at any time. The changes of pulse oxygen saturation (SpO 2), RR and heart rate (HR) before and after application of new simple respirator were observed, and the blood gas test results of part of the patients were collected. Results:Twenty-two patients with severe and critical COVID-19 had significantly higher SpO 2 at 10 minutes after application of the new simple ventilator than before application (0.994±0.007 vs. 0.952±0.017, P < 0.01), and RR was significantly lower than that before application (times/min: 27.59±3.63 vs. 29.64±3.81, P < 0.01); after 1 day of application, each index was further improved. All 13 patients who received blood gas analysis indicated no carbon dioxide accumulation. Conclusions:The new simple respirator can significantly improve the oxygen therapy effect of patients with severe and critical COVID-19. At the same time, 2019 novel coronavirus (2019-nCoV) can be filtered through the filter to reduce the formation of aerosol and protect the medical staff and patients.

Effect of preoperative sleep deprivation on hippocampal TLR4/NF-κB signaling pathway in aged mice with postoperative cognitive dysfunction / 中华麻醉学杂志

Objective To evaluate the effect of preoperative sleep deprivation on hippocampal Tolllike receptor 4 (TLR4)/nuclear factor-kappa B (NF-κB) signaling pathway in aged mice with postoperative cognitive dysfunction.Methods Sixty clean-grade healthy male C57BL/6J mice,aged 16 months,weighing 28-36 g,were divided into 4 groups (n=15 each) using a random number table method:control group (group C),surgery group (group S),sleep deprivation group (group SD) and sleep deprivation plus surgery group (group SD+S).Mice were fed a common diet in group C.Mice were sleep-deprived for 24 h in group SD.Tibial fracture internal fixation was performed in group S.Tibial fracture internal fixation was performed after 24-h sleep deprivation in group SD+S.Cognitive function was assessed using the contextual fear conditioning test at days 3 and 7 after operation.The animals were sacrificed at day 7 after operation,brains were removed and hippocampi were isolated for determination of tumor necrosis factor-alpha (TNF-α) content (by enzyme-linked immunosorbent assay) and expression of TLR4 and p-NF-κB p65 (by Western blot).Results Compared with group C,the percentage of time spent freezing induced by condition and percentage of time spent freezing induced by context were significantly decreased at days 3 and 7 after operation,the content of TNF-α was increased,and the expression of TLR4 and p-NF-κB p65 was up-regulated in S,SD and SD+S groups (P＜0.05).Compared with group S and group SD,the percentage of time spent freezing induced by condition and percentage of time spent freezing induced by context were significantly decreased at days 3 and 7 after operation,the content of TNF-α was increased,and the expression of TLR4 and p-NF-κB p65 was up-regulated in group SD+S (P＜0.05).Conclusion Preoperative sleep deprivation further accentuates postoperative cognitive dysfunction,and the mechanism is related to activating TLR4/NF-κB signaling pathway and inducing inflammatory responses of aged mice.

Linagliptin improved myocardial function recovery in rat hearts after a prolonged hypothermic preservation.

AIMS: To determine whether linagliptin, a dipeptidyl peptidase 4 inhibitor, can promote the recovery of cardiac function after hypothermic preservation. MAIN METHODS: Rat hearts were preserved in cold Celsior solution with or without linagliptin for 9 h. Cardiac function was evaluated at 60 min of reperfusion after hypothermic preservation. Cardiac mitochondrial morphology was observed using transmission electron microscope. The expression of dynamin-related protein 1 (Drp1), NADPH oxidase 2 (NOX2), calmodulin-dependent protein kinase II (CaMKII) were detected using Western blot. KEY FINDINGS: Compared with Celsior group, supplement of Celsior solution with linagliptin (0.25-0.75 nM) could significantly prevent hypothermic preservation-induced cardiac dysfunction. The expression of NOX2 protein, ROS level and MDA content in cardium were increased after hypothermic preservation, which was inhibited by linagliptin. Although the mitofusin1, 2, optic atrophy type 1, and total Drp1 expression in myocardium did not change, the level of p-Drp1 S616 and mitochondrial Drp1 were enhanced after hypothermic preservation. Linagliptin supplement could inhibit the hypothermic preservation-induced increase in p-Drp1 S616 and mitochondrial Drp1 protein, and mitigate the mitochondrial fragmentation. Level of p-CaMKII protein enhanced after hypothermic preservation, which could be prevented by linagliptin or a NOX2 inhibitor Phox-I2. Both Phox-I2 and a CaMKII inhibitor KN-93 could reduce the hypothermic preservation-induced increase in p-Drp1 S616 and mitochondrial Drp1 protein. SIGNIFICANCE: Supplement Celsior solution with linagliptin could improve cardiac function recovery in 9-h hypothermic preserved rat hearts. The cardioprotective effect of linagliptin might be due to the inhibition of Drp1 phosphorylation and mitochondrial translocation by preventing NOX2-mediated CaMKII activation.

De Novo Transcriptome Assembly and Characterization of the Synthesis Genes of Bioactive Constituents in Abelmoschus esculentus (L.) Moench.

Abelmoschus esculentus (okra or lady's fingers) is a vegetable with high nutritional value, as well as having certain medicinal effects. It is widely used as food, in the food industry, and in herbal medicinal products, but also as an ornamental, in animal feed, and in other commercial sectors. Okra is rich in bioactive compounds, such as flavonoids, polysaccharides, polyphenols, caffeine, and pectin. In the present study, the concentrations of total flavonoids and polysaccharides in five organs of okra were determined and compared. Transcriptome sequencing was used to explore the biosynthesis pathways associated with the active constituents in okra. Transcriptome sequencing of five organs (roots, stem, leaves, flowers, and fruits) of okra enabled us to obtain 293,971 unigenes, of which 232,490 were annotated. Unigenes related to the enzymes involved in the flavonoid biosynthetic pathway or in fructose and mannose metabolism were identified, based on Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. All of the transcriptional datasets were uploaded to Sequence Read Archive (SRA). In summary, our comprehensive analysis provides important information at the molecular level about the flavonoid and polysaccharide biosynthesis pathways in okra.

Effects of ulinastatin with parecoxib sodium on early cellular immunology function and cognitive function in elderly patients undergoing total hip replacement / 临床麻醉学杂志

Objective To investigate the effects of ulinastatin with parecoxib sodium on early cellular immunology function and cognitive function in elderly patients undergoing total hip replacement.Methods One hundred patients (aged 65-80 years,ASA grade Ⅱ) undergoing elective total hip replacement were randomly assigned into 4 groups: group W(n=25),group P(n=25),group WP(n=25) and group C(n=25).The patients in group W received intravenous injection of ulinastatin with a dose of 5 000 U/kg before skin incision and at the moment of the end of operation.Patients in group P accepted intravenous injection of parecoxib sodium of 40 mg before anesthesia and at a 12 h intervals for six times.Patients in group WP accepted intravenous injection of ulinastatin with a dose of 5 000 U/kg before skin incision and at the moment of the end of operation,and accepted intravenous injection of parecoxib sodium with a dose of 40 mg before anesthesia and at a 12 h interval for six times.Patients in group C were given normal saline at the same time as placebo.The operation time,the volume of bleeding and autologous blood receiving and the intraoperative fentanyl consumption were recorded in four groups.Blood samples were obtained before induction (T0),at the end of operation (T1),on 6 h (T2),24 h (T3),72 h (T4) after operation for determination of plasma concentration of S100β protein,neuron-specific enolase(NSE),IL-6,TNF-α.The percentages of T lymphocyte subsets (CD3+,CD4+,CD8+) and CD4+/CD8+ ratio were detected with flow cytometry.The Mini-Mental State Examination (MMSE) was used to test the cognitive function of the patients at T0,T4 and 7 d after operation (T5).Results Compared with T0,the percentages of CD3+,CD4+ cells and CD4+/CD8+ in groups C,W and P were significantly decreased,the plasma concentrations of IL-6 and TNF-α significantly increased at T1-T4,concentration of NSE and S100 protein were significantly increased at T2 and T3 (P<0.05).the percentages of CD3+,CD4+T lymphocyte and CD4+/CD8+ ratio in groups W and P at T2,T3 and group WP at T1-T4 was significantly higher than that of group C,the concentration of IL-6,TNF-α,NSE and S100β protein content was significantly lower than in group C (P<0.05);the percentages of CD3+,CD4+T lymphocyte and CD4+/CD8+ ratio in group WP was significantly higher than those of groups W and P,the concentrations of TNF-α,IL-6,NSE and S100β protein content was significantly lower than those of group W and P at T2,T3 (P<0.05).Compared with T0,MMSE score in group C was significantly lower at T4,T5 (P<0.05).MMSE score of groups W,P and WP was significantly higher than that of group C at T4 (P<0.05).MMSE score of group WP was significantly higher than those of groups W and P at T4 (P<0.05).Conclusion Ulinastatin combined with parecoxib sodium ameliorates early cellular immunology function and cognitive function in elderly patients undergoing total hip replacement,and it is more effective than using ulinastatin or parecoxib sodium alone.

Effects of different analgesia methods on early rehabilitation after hepatectomy under the strategy of en-hanced recovery after surgery / 临床麻醉学杂志

Objective To compare the effectiveness of postoperative analgesia and early rehabil-itation between the wound infiltration combined with intravenous analgesia and epidural analgesia after hepatectomy.Methods Forty-eight patients with liver carcinoma,37 males and 1 1 females,aged 40-65 years,ASA physical status Ⅰ or Ⅱ,were randomly divided into two groups.Patients in group T were given 0.375% ropivacaine 30 ml for incision infiltration before closing the abdomen and intrave-nous analgesia.Patients in group E were given 0.2% ropivacaine 100 ml for epidural analgesia. Pareoxib sodium 40 mg was injected intravenously 30 min toward the end of the operation.Pain scores were assessed by VAS at postoperative 2,6,12,24 and 48 h.Postoperative activity distance was re-corded on 1st,2nd,3th day after surgery;the time first getting off bed and hospital stay were recor-ded.Finally,the complications were also recorded.Results Compared with group T,VAS scores at rest and in activity 12,24 and 48 h postoperatively were significantly lower (P <0.05 ).Compared with group E,postoperative activity distance on 1st,2nd and 3th day after surgery in group T were shorter.Furthermore,the time first getting off bed and the hospital stay in group T were shorter than those in group E (P <0.05).The incidence of adverse reactions between the two groups had no sta-tistical significance.Conclusion The wound infiltration combined with intravenous analgesia is benefi-cial to early recovery and shorter hospital stay.

Role of Wnt/β-catenin signaling pathway in lithium chloride preconditioning-induced improvement in postoperative cognitive function of aged rats / 中华麻醉学杂志

Objective To evaluate the role of Wnt/β-catenin signaling pathway in lithium chloride preconditioning-induced improvement in postoperative cognitive function of aged rats.Methods A total of 100 pathogen-free healthy male Sprague-Dawley rats,aged 18 months,weighing 540-650 g,were divided into 5 groups (n =20 each) using a random number table:control group (group C),surgery group (group S),lithium chloride preconditioning group (group L),secreted frizzled-related protein 1 (sFRP-1) group (group F) and lithium chloride preconditioning plus sFRP-1 group (group L+F).Lithium chloride 2 mmol/kg was intraperitoneally injected once a day for 5 consecutive days before operation in L and L+ F groups.In F and L + F groups,sFRP-1 10 μl (concentration 10 μg/ml) was injected into the ventricle at 1 day before operation.Ten rats in each group were randomly sacrificed at 1 day after operation,and the hippocampi were removed for determination of the expression of phosphorylated glycogen synthase kinase-3 beta (p-GSK-3β),3-catenin and Wnt in hippocampal tissues (by Western blot).The rest rats underwent Morris water maze test at day 3-7 after operation,and the concentrations of amyloid beta 42 (A3-42) and phosphorylated tau-181 protein (p-tau-181) in cerebrospinal fluid (CSF) were detected by enzyme-linked immunosorbent assay at day 7 after operation.Results Compared with group C,the escape latency was significantly prolonged at 3-7 days after operation,and the concentration of Aβ-42 in CSF was increased in the other four groups,and the expression of Wnt,p-GSK-3β and β-catenin in hippocampal tissues was down-regulated in group S,the expression of Wnt,p-GSK-3β and β-catenin in hippocampal tissues was significantly up-regulated in L and L+F groups,and the concentration of p-tau-181 in CSF was significantly increased in S and L+F groups (P＜0.05).Compared with group S,the escape latency was significantly shortened at 3-7 days after operation in group L and at 5-7 days after operation in group L+F,and the expression of Wnt,p-GSK-3β and β-catenin was significantly up-regulated,and the concentrations of Aβ-42 and p-tau-181 in CSF were decreased in L and L+F groups (P＜0.05).Compared with group L,the escape latency was significantly prolonged at 3-6 days after operation,the expression of Wnt,p-GSK-3β and β-catenin was down-regulated,and the concentration of p-tau-181 in CSF was increased in group L+F (P＜ 0.05).Compared with group F,the escape latency was significantly shortened at 3-7 days after operation,the expression of Wnt,p-GSK-3β and β-catenin was up-regulated,and the concentrations of Aβ-42 and ptau-181 in CSF were decreased in group L+F (P＜0.05).Conclusion The mechanism by which lithium chloride preconditioning improves in postoperative cognitive function is partially related to activating Wnt/β-catenin signaling pathway in aged rats.

Effect of controlled low threshold blood pressure on the expression of A β42 and p-Tau-181 protein in cerebrospinal fluid and cognition after operation in aged rats / 实用医学杂志

Objective To investigate the effects of different duration hypotension thresholds on p-Tau-181 and Aβ-42 protein expression and cognition in rats. Methods Thirty-nine healthy male SD rats were randomly di-vided into 4 groups:the control group(group C,n=9),the hypotension group(groupA1、A2、A3 ,n=10). The blood pressure of groupA1、A2、A3 was measured in different time of 2 h、4 h、6 h ,for 5 days. The antihyperten-sive group of mean arterial pressure(MAP)were maintained in the 50~55 mmHg safe range. Morris water maze was used to detect the spatial learning and memory ability of rats. The levels of Aβ42 and p-Tau-181 were detected by ELISA. Results There was no significant difference in mortality of rats in each group (P > 0.05). Compared with the group C,the escape latency and swimming distance of A2 group and A3 group were increased(P<0.05). In 3~7 days after operation,the cerebrospinal fluid P-Tau-181 and Aβ42 protein expression increased in the A2 group and A3 group compared with the A1 group(P<0.05). The escape latency and swimming distance of the A2 group and the A3 group were significantly longer than those in the control group. Aβ42 and p-Tau-181 were signifi-cantly increased in A3 group(P < 0.05). Compared with the A2 group,the increase of Aβ42 and p-Tau-181 in the A3 group was not significant(P<0.05). Conclusion Long-term controlled hypotension may lead to postoper-ative cognitive dysfunction which may relate to the increase of Aβ42 and p-Tau-181 protein expression.

Exploring the reactivity of multicomponent photocatalysts: insight into the complex valence band of BiOBr.

The band structure of multicomponent semiconductor photocatalysts, as well as their reactivity distinction under different wavelengths of light, is still unclear. BiOBr, which is a typical multicomponent semiconductor, may have two possible valence-band structures, that is, two discrete valence bands constructed respectively from O 2p and Br 4p orbitals, or one valence band derived from the hybridization of these orbitals. In this work, aqueous photocatalytic hydroxylation is applied as the probe reaction to investigate the nature and reactions of photogenerated holes in BiOBr. Three organic compounds (microcystin-LR, aniline, and benzoic acid) with different oxidation potentials were selected as substrates. Isotope labeling (H(2)(18)O as the solvent) was used to determine the source of the O atom in the hydroxyl group of the products, which distinguishes the contribution of different hydroxylation pathways. Furthermore, a spin-trapping ESR method was used to quantify the reactive oxygen species ((.)OH and (.)OOH) formed in the reaction system. The different isotope abundances of the hydroxyl O atom of the products formed, as well as the reverse trend of the (.)OH/(.)OOH ratio with the oxidative resistance of the substrate under UV and visible irradiation, reveal that BiOBr has two separate valence bands, which have different oxidation ability and respond to UV and visible light, respectively. This study shows that the band structure of semiconductor photocatalysts can be reliably analyzed with an isotope labeling method.

[Measurement of pork tenderness by using steady spatially-resolved spectroscopy].

Tenderness is one of the main sensory and eating qualities of meat. Conventional measurement of tenderness is a time-consuming and invasive method. Using steady spatially-resolved spectroscopy, a multi-channel visible and near infrared spectroscopy instrument was established to obtain the reduced scattering coefficient mu's. of porcine longissimus muscle samples. After spectra collection, each fresh meat sample was divided into two parts, one was tested by means of C-LM4 tenderness instrument, and the other was measured by conventional method. The results showed that reduced scattering coefficient of the samples was significantly correlated to fresh meat shear force values (R2 = 0.8349) at 700 nm. Also, there was a significant correlation between fresh meat shear force values and shear force values by conventional method (R2 = 0.7716). In conclusion, the potential of the steady spatially-resolved spectroscopy technique as a rapid and non-invasive tool to measure tenderness of pork was found.

Mobile carbohydrates in Himalayan treeline trees I. Evidence for carbon gain limitation but not for growth limitation.

To test whether the altitudinal distribution of trees is determined by a carbon shortage or an insufficient sugar fraction (sugar:starch ratio) in treeline trees, we studied the status of nonstructural carbohydrates (NSC) and their components (total soluble sugars and starch) in Abies fabri (Mast.) Craib and Picea balfouriana var. hirtella Rehd. et Wils. trees along three elevational gradients, ranging from lower elevations to the alpine treeline, on the eastern edge of the Tibetan Plateau. For comparison, we investigated a low-altitude species (Tsuga yunnanensis (Franch.) Pritz.) which served as a warm-climate reference because it is distributed in closed montane forests below 3100 m a.s.l. in the study area. The carbon status of T. yunnanensis responded to altitude differently from that of the treeline species. At the species level, total NSC was not consistently more abundant in treeline trees than in trees of the same species growing at lower elevations. Thus there was no consistent evidence for carbon limitation of growth in treeline trees. For the three treeline species studied (P. balfouriana and A. fabri in the Kang-Ding Valley and A. fabri in the Mo-Xi Valley), winter NSC concentrations in treeline trees were significantly lower than in lower-elevation trees of the same species, suggesting that, in winter, carbon is limited in treeline trees. However, in no case was there total overwinter depletion of NSC or its components in treeline trees. Treeline and low-altitude species had similar sugar:starch ratios of about three at their upper-elevational limits in April. We conclude that survival and growth of trees at the elevational or latitudinal climate limit depend not only on NSC concentration in perennial tissues, but also on the maintenance of an overwintering sugar:starch ratio greater than three.

Evaluation on germplasm resources of main production area of Artemisia annua in China / 中国中药杂志

<p><b>OBJECTIVE</b>To evaluate and select excellent germplasm resources of Artemisia annua L., providing basic data for data base and breeding of A. annua.</p><p><b>METHOD</b>Seventy-two germplasms of A. annua, which were collected from main production areas, were planted in germplasm resources garden in Jingxi and Nanning under the same conditions. The samples were gathered in the squaring stage. Artemisinin was extracted by supersonic wave and determined by ultraviolet spectrophotometry.</p><p><b>RESULT</b>The leaf's yield and the content of artemisinin in the samples of different germplasms were varied significantly. Effect of environment on artemisinin content was more than that of hereditary factors. The content of artemisinin was different when the same material of A. annua grew in different place. The content of artemisinin in next year's plant was decreasing.</p><p><b>CONCLUSIONS</b>Seven germplasms from south of China have been selected, their content of artemisinin was above 0.9% and calculated yield was more than 2250 kg x hm(-2). The content of artemisinin has been affected by hereditary factors and variation of the growth environment.</p>