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1,3-Functionalized cyclobutane structural motifs are ubiquitous in natural products and pharmaceuticals. Photoinduced alkylation of bicyclo[1.1.0]butanes (BCBs) offers a step-economical strategy for accessing 1,3-functionalized cyclobutane motifs. Herein, we disclose a general and mild photocatalytic protocol of bromoallylation and alkylation of BCBs in a metal, additive-free manner by using the same photocatalyst, 2-isopropylthioxanthone, in different catalytic roles. Furthermore, the synthetic utility of these products was illustrated in the synthesis of various valuable and complex cyclobutane derivatives.
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A general and mild strategy involving three-component carboarylation of unactivated alkenes with protic C(sp3)-H feedstocks via photoredox catalysis was reported. This catalytic system is compatible with a broad range of unactivated alkenes, cyano-substituted arenes, and diverse protic C(sp3)-H feedstocks. The synthetic value of this protocol was demonstrated by the late-stage functionalization of complex molecules and the synthesis of the antiallergies including pheniramine, chlorpheniramine, and brompheniramine.
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Alcenos , Clorfeniramina , Catálise , BromofeniraminaRESUMO
Scutellaria tsinyunensis is an endangered species in southwest China, distributed sporadically in mountainous areas at an elevation of approximately 200 to 900 m. Rhizosphere soil properties and fungal communities play critical roles in plant survival and expansion. Nevertheless, understanding of soil properties and fungal communities in the S. tsinyunensis distribution areas is extremely limited. The present study examined soil properties and fungal communities in nearly all extant S. tsinyunensis populations at two altitudinal gradients (low and high groups). Our findings indicated that soil characteristics (i.e., soil pH, water content, and available phosphorus) were affected distinctively by altitudes (P < 0.05). In addition, the low altitude group harbored higher fungal richness and diversity than the high altitude. Co-occurrence network analysis identified six key genera that proved densely connected interactions with many genera. Further analysis represented that the low altitude group harbored three beneficial genera belonging to Ascomycota (Archaeorhizomyces, Dactylella, and Helotiales), whereas the high altitude showed more pathogenic fungi (Apiosporaceae, Colletotrichum, and Fusarium). Correlation analysis found that soil water content was highly correlated with Hydnodontaceae and Lophiostoma. Besides, plants' canopy density was negatively correlated with four pathogenic fungi, indicating that the high abundance of the pathogen at high altitudes probably inhibited the survival of S. tsinyunensis. To sum up, this comprehensive analysis generates novel insights to explore the contrasting responses of S. tsinyunensis rhizosphere fungal communities and provides profound references for S. tsinyunensis habitat restoration and species conservation. IMPORTANCE Our study highlighted the importance of rhizosphere fungal communities in an endangered plant, S. tsinyunensis. Comparative analysis of soil samples in nearly all extant S. tsinyunensis populations identified that soil properties, especially soil water content, might play essential roles in the survival and expansion of S. tsinyunensis. Our findings proved that a series of fungal communities (e.g., Archaeorhizomyces, Dactylella, and Helotiales) could be essential indicators for S. tsinyunensis habitat restoration and protection for the first time. In addition, further functional and correlation analyses revealed that pathogenic fungi might limit the plant expansion into high altitudes. Collectively, our findings displayed a holistic picture of the rhizosphere microbiome and environmental factors associated with S. tsinyunensis.
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Microbiota , Scutellaria , Biodiversidade , Fungos/fisiologia , Plantas , Rizosfera , Solo/química , Microbiologia do Solo , ÁguaRESUMO
Thuja sutchuenensis Franch. is an endangered species in southwest China, distributed sporadically in mountainous areas. Soil property and soil fungal community play a crucial role in plant growth and survival. Nevertheless, understanding soil properties and the soil fungal community in the areas where T. sutchuenensis is distributed is extremely limited. Hence, this study collected a total of 180 soil samples from five altitudinal distribution areas (altitudinal gradients) and three vertical depths throughout four horizontal distances from the base of each tree. The results found that altitudinal gradients and vertical depths altered soil properties, including pH, organic matter content, water content, total nitrogen, phosphorus, and potassium, and available nitrogen, phosphorus, and potassium. The fungal alpha diversity indexes (Chao1 and Shannon) and beta diversity were dramatically decreased with elevation. In addition, high altitudes (2,119 m) harbored the highest relative abundance of ectomycorrhizal fungi (27.57%) and the lowest relative abundance of plant-pathogenic fungi (1.81%). Meanwhile, we identified a series of fungal communities, such as Tomentella, Piloderma, Cortinarius, Sebacina, and Boletaceae, that play an essential role in the survival of T. sutchuenensis. The correlation analysis and random forest model identified that water content and total phosphorus showed strong relationships with fungal characteristics and were the primary variables for Zygomycota and Rozellomycota. Collectively, the findings of this integrated analysis provide profound insights into understanding the contrasting responses of T. sutchuenensis soil fungal communities and provide a theoretical basis for T. sutchuenensis habitat restoration and species conservation from multispatial perspectives. IMPORTANCE The present study highlights the importance of fungal communities in an endangered plant, T. sutchuenensis. Comparative analysis of soil samples in nearly all extant T. sutchuenensis populations identified that soil properties, especially soil nutrients, might play critical roles in the survival of T. sutchuenensis. Our findings prove that a series of fungal communities (e.g., Tomentella, Piloderma, and Cortinarius) could be key indicators for T. sutchuenensis survival. In addition, this is the first time that large-scale soil property and fungal community investigations have been carried out in southwest China, offering important values for exploring the distribution pattern of regional soil microorganisms. Collectively, our findings display a holistic picture of soil microbiome and environmental factors associated with T. sutchuenensis.
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Basidiomycota , Micobioma , Micorrizas , Thuja , Traqueófitas , Fungos , Nitrogênio , Fósforo , Plantas , Potássio , Solo/química , Microbiologia do Solo , ÁguaRESUMO
Thuja sutchuenensis Franch. is an endangered species in southwestern China, primarily distributed in 800-2,100 m of inaccessible mountainous areas. Rhizosphere soil physicochemical properties and bacterial communities play an essential role in managing plant growth and survival. Nonetheless, the study investigating rhizosphere soil properties and bacterial communities of T. sutchuenensis is limited. The present study investigated soil properties, including soil pH, organic matter, water content, nitrogen, phosphorus, and potassium contents, and bacterial communities in nearly all extant T. sutchuenensis populations at five elevational gradients. Our results demonstrated that the increase in elevation decreased rhizosphere and bulk soil phosphorus content but increased potassium content. In addition, the elevational gradient was the dominant driver for the community composition differentiation of soil bacterial community. Proteobacteria and Acidobacteria were the dominant bacterial phyla distributed in the rhizosphere and bulk soils. Co-occurrence network analysis identified key genera, including Bradyrhizobium, Acidicapsa, Catenulispora, and Singulisphaera, that displayed densely connected interactions with many genera in the rhizosphere soil. The dominant KEGG functional pathways of the rhizosphere bacteria included ABC transporters, butanoate metabolism, and methane metabolism. Further correlation analysis found that soil phosphorus and potassium were the dominant drivers for the diversity of soil bacteria, which were distinctively contributed to the phylum of Planctomycetes and the genera of Blastopirellula, Planctomycetes, and Singulisphaera. Collectively, this comprehensive study generated multi-dimensional perspectives for understanding the soil bacterial community structures of T. sutchuenensis, and provided valuable findings for species conservation at large-scale views.
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Currently, little in-depth evidence is known about the application of extracorporeal membrane oxygenation (ECMO) therapy in coronavirus disease 2019 (COVID-19) patients. This retrospective multicenter cohort study included patients with COVID-19 at 7 designated hospitals in Wuhan, China. The patients were followed up until June 30, 2020. Univariate and multivariate logistic regression analyses were performed to identify the risk factors associated with unsuccessful ECMO weaning. Propensity score matching was used to match patients who received veno-venous ECMO with those who received invasive mechanical ventilation (IMV)-only therapy. Of 88 patients receiving ECMO therapy, 27 and 61 patients were and were not successfully weaned from ECMO, respectively. Additionally, 15, 15, and 65 patients were further weaned from IMV, discharged from hospital, or died during hospitalization, respectively. In the multivariate logistic regression analysis, a lymphocyte count ≤0.5×109/L and D-dimer concentration >4× the upper limit of normal level at ICU admission, a peak PaCO2 >60 mmHg at 24 h before ECMO initiation, and no tracheotomy performed during the ICU stay were independently associated with lower odds of ECMO weaning. In the propensity score-matched analysis, a mixed-effect Cox model detected a lower hazard ratio for 120-day all-cause mortality after ICU admission during hospitalization in the ECMO group. The presence of lymphocytopenia, higher D-dimer concentrations at ICU admission and hypercapnia before ECMO initiation could help to identify patients with a poor prognosis. Tracheotomy could facilitate weaning from ECMO. ECMO relative to IMV-only therapy was associated with improved outcomes in critically ill COVID-19 patients.
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COVID-19/terapia , Oxigenação por Membrana Extracorpórea/métodos , Adulto , Idoso , COVID-19/mortalidade , Estudos de Casos e Controles , China , Estado Terminal , Oxigenação por Membrana Extracorpórea/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Pontuação de Propensão , Estudos Retrospectivos , Fatores de Risco , Análise de Sobrevida , Resultado do Tratamento , Adulto JovemRESUMO
The complete chloroplast (cp) genome of Eurya loquaiana Dunn. has been reported in this study. The cp genome has a total length of 157,218 bp with the typical quadripartite structure, containing two inverted repeats (IRs) of 25,883 bp separated by a large single-copy (LSC) region of 87,248 bp and a small single-copy (SSC) region of 18,204 bp. The whole cp genome of E. loquaiana contains 128 genes, including 83 protein-coding genes, 37 tRNAs genes, and 8 rRNAs. The phylogenetic result showed that E. loquaiana is sister to E. alate.
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This study was the first report about complete chloroplast genome of Impatiens pritzelii (Balsaminaceae). The plastome of I. pritzelii was found to possess a total length 152,487 bp with the typical quadripartite structure of angiosperms, containing two inverted repeats (IRs) of 25,684 bp separated by a large single-copy (LSC) region and a small single-copy (SSC) region of 83,290 and 17,829 bp, respectively. The plastid genome of I. pritzelii contains 113 genes, including 79 protein-coding genes, 4 ribosomal RNA genes, and 30 transfer RNA genes. The overall GC content of I. pritzelii plastid genome is 37.0% and the corresponding values in LSC, SSC, and IR regions are 34.9%, 29.8%, and 43.1%, respectively.
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This study was the first report about the complete chloroplast genome of Plantago fengdouensis (Plantaginaceae). The circular whole cp genome of P. fengdouensis was in a total length 164,976 bp with the typical quadripartite structure of angiosperms, containing two inverted repeats (IRs) of 38,644 bp separated by a large single-copy (LSC) region and a small single-copy (SSC) region of 82,972 and 4716 bp, respectively. The plastid genome of P. fengdouensis contains 113 genes, including 79 protein-coding genes, 4 ribosomal RNA genes, and 30 transfer RNA genes. The overall GC content of P. fengdouensis plastid genome is 38.0% and the corresponding values in LSC, SSC, and IR regions are 36.6, 30.2, and39.9%, respectively.
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Chlorine radical, which is classically generated by the homolysis of Cl2 under UV irradiation, can abstract a hydrogen atom from an unactivated C(sp3 )-H bond. We herein demonstrate the use of HCl as an effective hydrogen-atom-transfer catalyst precursor activated by an organic acridinium photoredox catalyst under visible-light irradiation for C-H alkylation and allylation. The key to success relied on the utilization of microtubing reactors to maintain the volatile HCl catalyst. This photomediated chlorine-based C-H activation protocol is effective for a variety of unactivated C(sp3 )-H bond patterns, even with primary C(sp3 )-H bonds, as in ethane. The merit of this strategy is illustrated by rapid access to several pharmaceutical drugs from abundant unfunctionalized alkane feedstocks.
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Eosinâ Y, a well-known economical alternative to metal catalysts in visible-light-driven single-electron transfer-based organic transformations, can behave as an effective direct hydrogen-atom transfer catalyst for C-H activation. Using the alkylation of C-H bonds with electron-deficient alkenes as a model study revealed an extremely broad substrate scope, enabling easy access to a variety of important synthons. This eosinâ Y-based photocatalytic hydrogen-atom transfer strategy is promising for diverse functionalization of a wide range of native C-H bonds in a green and sustainable manner.
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A direct hydroalkylation of disubstituted alkynes with unfunctionalized ethers and amides was achieved in an atom-efficient and additive-free manner through the synergistic combination of photoredox and nickel catalysis. The protocol was effective with a wide range of internal alkynes, providing products in a highly selective fashion. Notably, the observed regioselectivity is complementary to conventional radical addition processes. Mechanistic investigations suggest that the photoexcited iridium catalyst facilitated the nickel activation via single-electron transfer.
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Traditional squash method was used to analyze chromosome number and karyotypes of four Scutellaria species in Chongqing Jinyun Mountain Natural Reserveï¼ Scutellaria tsinyunensis, S.yunnanensis, S.franchetiana and S.indica.The result showed that the chromosome numbers were 26 except for S.franchetiana, which had 24 chromosomes.These species were all diploid with metacentric and submetacentric chromosomes.Their karyotypes were symmetrical and primitive.The karyotype formula of S.tsinyunensis is 2n=2x=26=24m+2sm, 1B type, As.k=55.28%; the karyotype formula of S.yunnanensis var.salicifolia is 2n=2x=26=26m, 1B type, As.k=56.11%; the karyotype formula of S.franchetiana is 2n=2x=24=20m+4sm, 2B type, As.k=58.50%; the karyotype formula of S.indica is 2n=2x=24=20m+4sm, 2B type, As.k=58.41%.The results were compared with the reported data of S.baicalensis and S.alaschanica.S.alaschanica is expected to be the most advanced one whereas S.tsinyunensis, and S.yunnanensis var. salicifolia primitive.These results are expected to provide some references to the origin and differentiation of genus Scutellaria.
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Evolução Biológica , Cariótipo , Scutellaria/genética , China , Diploide , Scutellaria/classificaçãoRESUMO
Allylboronates undergo C-H allylation of unsubstituted or monosubstituted benzoquinone and naphthoquinone substrates. In the case of 2,5- or 2,6-disubstituted quinones addition involving the substituted carbon takes place. Allylation with stereodefined allylboronates occurs with retention of the configuration.
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Compostos Alílicos/síntese química , Ácidos Borônicos/química , Quinonas/química , Compostos Alílicos/química , Estrutura MolecularRESUMO
Palladium catalyzed allylic C-H functionalization was performed using exocyclic alkene substrates. Multi-component synthesis of stereodefined homoallylic alcohols could be performed using a reaction sequence involving allylic C-H borylation and allylation of aldehydes.
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BACKGROUND: Endoscopic radial artery harvesting is a favourable harvesting technique which provides excellent cosmetic result and low incidence of incision related complications, however the impact of this technique on graft quality is less well-explained. We sought to evaluate the impact of harvesting technique on graft patency and relevant clinical outcomes in patients undergoing coronary artery bypass graft (CABG). METHOD: A systematic literature search was conducted to identify publications containing comparisons between different sampling skills in CABG, data was extracted and analysed with Revman, Downs and Black score was applied to evaluate the methodological quality of included studies. RESULT: Ten studies containing 2782 patients were undertaken, the quality was generally acceptable. Pooled analysis results indicate endoscopic radial artery harvesting was associated with a lower incidence of wound infection and a similar incidence of haematoma formation compared with open harvesting. The difference in graft patency and all-cause mortality was insignificant between two cohorts. CONCLUSION: Endoscopic radial artery harvesting is a safe technique and provides equivalent graft patency as compared with open harvesting, further investigation is required to confirm the aforementioned conclusion and evaluate the impact of harvesting technique on hand sensory and motor function.
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Angioscopia/métodos , Ponte de Artéria Coronária , Artéria Radial , Ponte de Artéria Coronária/métodos , Ponte de Artéria Coronária/mortalidade , Feminino , Humanos , MasculinoRESUMO
We have developed a multifunctional thiourea-phosphine catalyzed asymmetric [3 + 2] annulation of Morita-Baylis-Hillman (MBH) carbonates with maleimides, which can efficiently construct functionalized cyclopentenes bearing three contiguous stereocenters in moderate to excellent yields and excellent diastereo- and enantioselectivities. A plausible mechanism has been also proposed on the basis of control experiments and previous literature.
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OBJECTIVE: To study the technical feasibility of simplified total arch replacement via stented elephant trunk fenestration in the treatment of acute Stanford type A aortic dissection. METHODS: A total of 42 consecutive patients with acute type A aortic dissection underwent total aortic arch replacement plus fenestrate stented elephant trunk implantation under hypothermic cardiopulmonary bypass and bilateral antegrade cerebral perfusion between August 2008 to February 2011. The aortic arch was accessed longitudinally. Transection of aortic arch was performed between left common carotid artery and left subclavian artery. A stented elephant trunk was inserted in descending aorta. Then the reconstruction of left subclavian artery was made by fenestration in stented elephant trunk. Finally 3-branched graft was used to complete the reconstruction of aortic arch. RESULTS: Operations were performed successfully. The mean cardiopulmonary bypass (CPB) time was (156 ± 42) min, mean aortic cross-clamp time (91 ± 18) min, mean circulatory arrest time (20 ± 5) min and mean antegrade cerebral perfusion (ACP) time (33 ± 7) min. No postoperative death occurred. The incidence of temporary neurological dysfunction was 4.8% (2/42). They underwent neither re-exploration for postoperative hemorrhage nor hoarseness due to recurrent nerve palsy. Left radial arterial pulses were palpable in all of them. None had sensory deficit and dyskinesia of left arm. All their angiographic findings showed complete patency of left subclavian artery. There was neither space nor blood flow around the stented elephant trunk. The false lumen of descending aorta around elephant trunk closed and obliterated in all cases. CONCLUSIONS: The above-mentioned technique of modified total aortic arch replacement provides a distinct operative field and may achieve simple but reliable anastomosis with less bleeding. Thus aortic arch replacement becomes easier and more effective.
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Aorta Torácica/cirurgia , Aneurisma da Aorta Torácica/cirurgia , Dissecção Aórtica/cirurgia , Adulto , Idoso , Implante de Prótese Vascular , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Stents , Resultado do TratamentoRESUMO
A novel asymmetric [4+1] annulation of MBH carbonates with dicyano-2-methylenebut-3-enoates has been developed for the first time, providing an efficient and enantioselective synthesis of highly functionalized cyclopentenes bearing one all-carbon quaternary stereogenic center.