Exploring a Non-Comfort Zone: Central Chirality-Generating Macrocyclizations.

Macrocyclization reactions that are capable of stereoselectively co-creating one or more stereogenic centers have become useful strategies for the effective syntheses of structurally and functionally diverse organic molecules. This JOCSynopsis summarizes the recent progress in the field of natural product and analogue syntheses, including both bioinspired and non-bioinspired macrocyclic disconnections. Selected examples are organized on the basis of the sources of the asymmetric inductions.

Curative effect analysis of robot-assisted drainage surgery in treatment of spontaneous hypertensive brainstem hemorrhage.

Objective: Spontaneous hypertensive brainstem hemorrhage (HBSH) is characterized by sudden onset, rapid progression and poor prognosis. There has been a growing tendency of surgical treatment for HBSH. This study aimed to investigate outcomes and potential factors associated with the prognosis of robot-assisted drainage surgery for HBSH treatment. Methods: Patients with HBSH from July 2016 to March 2023 at a single neurosurgery center were included and divided into conservative group and surgical groups. Baseline and clinical data, radiographic characteristics, complications, and outcome evaluations were recorded and analyzed. Results: A total of 125 patients, with 74 in the conservative group and 51 in the surgical group, were enrolled in the study. Mortality at 6 months was 59/74 (79.7%) in the conservative group and 9/51 (17.6%) in the surgical group. Twenty-four patients (47.1%) achieved favorable outcomes in the surgical group, whereas this rate in the conservative group was only 5.4% (4/74). There was a significant difference in NIHSS, GCS, and mRS at 6 months between surviving patients in the conservative and surgical groups. In prognostic analysis in the surgical subgroup, initial GCS score [5 (IQR 4-7) vs. 3 (IQR 3-4), p < 0.001], NIHSS [36 (IQR 32-38) vs. 40 (IQR 38-40), p < 0.001], smoking history [45.8% (11/24) vs. 74.1% (20/27), p = 0.039], hematoma volume [6.9 (IQR 6.2-7.6) vs. 9.6 (IQR 7.3-11.4), p = 0.001], and hemorrhage location (p = 0.001) were potential risk factors for poor 6-month prognosis after robot-assisted surgery for HBSH. Conclusion: Based on the results of this study, robot-assisted minimally invasive drainage of brain stem hematoma may significantly reduce mortality and improve prognosis. Surgery should be conducted for selected patients.

Biomimetic Synthesis of Chejuenolides A-C by a Cryptic Lactone-Based Macrocyclization: Stereochemical Implications in Biosynthesis.

A hypothetical Mannich macrocyclization in the biosynthesis of chejuenolides A-C served as the basis for the synthetic design herein. Using a lactone-based linear precursor constructed via a tactic sequence of aldol-Julia-aldol reactions on a gram scale, the biomimetic total synthesis and structural validation of chejuenolides A-C were successfully achieved for the first time. The ß-oxo-δ-lactone unit in the macrocyclized adducts was fragile and readily converted to a series of C2/C18-diastereoisomers via a decarboxylation and protonation pathway. Stereochemical identification of the biosynthetic precursor (O3P2) confirmed structural adherence to the given macrocycles and previously clarified lankacidins. Moreover, the stereovariants of the linear precursor designed for the macrocyclization event highlighted the unparalleled impact of using this biomimetic approach to determine the stereoselectivity in the proposed enzymatic reaction by reviving the lost or unstable intermediate.

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This study aimed to examine the responses of persistent soil seed bank to future precipitation reduction of global climate change in the forest-steppe ecotone of Hulunbuir. Samples of soil seed bank were collected from 0-10 cm soil layer along a precipitation gradient. We examined the density, species composition, diversity of seed bank and their relationship with vegetation. Structural equation model was used to explore the direct impact of annual precipitation on soil seed bank and the indirect impact through vegetation, soil nitrogen, soil phosphorus, and soil pH. The results showed that seed bank density and species richness were negatively correlated with annual precipitation. The species diversity of soil seed banks in grasslands was higher than that in forests. The similarity between soil seed bank and vegetation was generally low. The results of structural equation model showed that the effects of annual precipitation on seed bank density and species richness were negative, with the standard path coefficients of -0.051 and -0.122, respectively. The direct effect of annual precipitation on seed bank density and species richness were positive. Precipitation had indirect and positive effect on seed bank density and species richness through soil nitrogen, a significantly indirect negative effect on seed bank species richness through soil pH and soil available phosphorus, and a significantly indirect negative effect on seed bank density through soil pH. The reduction of precipitation under furture climate change might alter the hedging strategies of plants. The persistent soil seed bank in the forest-steppeecotone had a potential buffering effect against future precipitation reduction.

Incidence and risk factors of lateral cage migration occurred after the first-stage lateral lumbar interbody fusion surgery.

BACKGROUND: Lateral lumbar interbody fusion (LLIF) is a novel, minimally invasive technique for the surgical treatment of lumbar diseases. The aim of this study was to identify the incidence and risk factors of lateral cage migration (LCM) occurred after the first-stage LLIF. HYPOTHESIS: The hypothesis was that LCM occurred after the first-stage LLIF was associated with some demographic characteristics, surgical variables and radiographic parameters. PATIENTS AND METHODS: Between June 2016 and August 2020, 335 patients (901 levels) underwent staged LLIF were retrospectively reviewed. Patients were classified into LCM and non-LCM group based on the experience of LCM before the second-stage posterior instrumentation. 100 patients in non-LCM were randomly sampled as a control group. Incidence of LCM was determined; demographic characteristics, surgical variables and radiographic parameters associated with LCM were compared between the LCM and control group. Univariate analyses and multivariable logistic regression analysis were used to identify the risk factors. RESULTS: LCM occurred after the first-stage LLIF was found in 19 (5.7%) patients. Bony endplate injury (OR, 106.255; 95% CI, 1.265-8924.765; p=0.039) and greater preoperative range of motion (ROM) (OR, 2.083, 95% CI, 1.068-4.066, p=0.031) were high risk factors for LCM. LCM occurred mainly 3 days later after the first-stage LLIF, while 4 cases experienced severe neural symptoms, intolerable low back pain and finally underwent reoperation. DISCUSSION: LCM occurred after the first-stage LLIF was significantly associated with bony endplate injury and greater preoperative ROM. Second-stage posterior fixation should be performed as soon as possible or a supplement lateral fixation/self-locking cage should be used in high-risk patients. LEVEL OF EVIDENCE: IV.

The Fruit of Gold: Biomimicry in the Syntheses of Lankacidins.

Natural products are constructed by organisms in impressive ways through various highly selective enzyme-catalyzed chemical reactions. Over the past century, there has been considerable interest in understanding and emulating the underlying biosynthetic logic for the target molecule. The successful implementation of a biomimetic strategy usually has some uniquely valuable benefits over other abiotic routes in total synthesis by (1) corroborating the chemical feasibility of a given biogenetic hypothesis and further unraveling some insightful implications for future biosynthetic studies and (2) providing remarkably more concise access to not only the original synthetic target but also diversified biogenetically related congeners, which may result in either the structural reassignment of previously disclosed natural products or the anticipation of undiscovered natural products. However, for the devised essential biomimetic transformation, fine-tuning the optimization of the substrates and the reaction conditions can sometimes be painstakingly challenging. Turning to nature for inspiration can provide additional impetus for methodological innovations.Previously used as oral veterinary drugs, lankacidins have potential as next-generation antibiotics to tackle the problems caused by multidrug-resistant bacteria with novel modes of action (MoAs). The hypersensitive and densely functionalized lactonic core within this family of macrocyclic polyketides poses a formidable challenge for chemical total synthesis and derivatization. In this account, we summarized the evolution of a unified biomimetic approach toward 10 lankacidin antibiotics and their linear biosynthetic intermediates in the longest linear 7-12 steps from readily available starting materials. Our endeavor commenced with an intermolecular bioinspired amido sulfone-based Mannich reaction approach to assemble 2 advanced fragments under mild biphasic organocatalytic conditions. It successfully gave rise to stereodivergent access to 4 C2/C18-isomeric lankacyclinols but failed to efficiently deliver lactone-containing congeners through Stille macrocyclization. Facilitated by the thermolysis chemistry of N,O-acetal to generate the requisite N-acyl-1-azahexatriene species, we realized the projected Mannich macrocyclization and eight macrocyclic lankacidins can be produced by orchestrated desilylative manipulations. In this process, we were able to perform structural reassignments of isolankacidinol (7 to 50) and isolankacyclinol (104 to 83) and, for the first time, elucidate the natural occurrence of 2,18-bis-epi-lankacyclinol (84). Moreover, the inability of the current biomimetic route to cofurnish the reported structure of 2,18-seco-lankacidinol A (15) triggered a proposed structural revision that is rooted in reconsidered biogenesis and was confirmed by a divergent synthesis that enabled us to identify the correct isomer (116). Finally, the modular, diversity-oriented design also provided streamlined entries to acyclic 2,18-seco-lankacidinol B (120) and the biosynthetic intermediate LC-KA05 (17) together with its C7-O-deacetylated congeners in all C4/C5-stereochemical variations (18, 127-129), culminating in a need for structural revision to the six-membered lactonic segment in LC-KA05-2. The selection and execution of biomimetic strategies in lankacidin total synthesis give rise to all the previously mentioned advantages at the current stage. The modular-based, late-stage diversified complex construction offers an exceptionally high level of synthetic flexibility for future synthetic forays toward newly isolated or chemically modified congeners within the lankacidin family.

First report of Stenotrophomonas maltophilia causing root soft rot of Sanqi (Panax notoginseng) in China.

Sanqi (Panax notoginseng (Burk.) F. H. Chen) is a traditional Chinese medicinal plant with a long planting cycle of 2-3 years that makes it vulnerable to root diseases caused by several pathogens, including Fusarium solani, Alternaria panax, Phytophthoracactorum, and Pseudomonas sp. In April 2019, root soft rot samples of Sanqi were collected from a plantation site in Songming, southwest of China. Typical symptoms included root softening and necrosis, yellow leaf, and stem wilting. Ten diseased roots samples were collected and sterilized with 0.1% HgCl2 for 1 min, 75% ethanol for 2min, and then rinsed thrice with sterile water. Sterilized roots were cut into small pieces of 5 × 5 mm and cultured on the nutrient agar (NA) medium for 48 h at 28°C. From the root cultures, a total of thirteen bacterial strains were obtained. Three strains, SM 2-5, SM 2-13, and SM 2-14 were selected for further study. These three strains were gram-negative, short rod-shaped (1～2×0.5～1µm), non-spore-forming and had polar tufted flagella as observed under a transmission electron microscope (TEM). Also, the strains were positive for oxidase, beta-galactosidase, arginine dihydrolase, and lysine decarboxylase while negative for amylase and urease tested by biochemical methods (Wang 2017). To further determine the pathogenic species, genomic DNA of these three strains was extracted using a Genomic DNA Kit (Tsing Ke, Beijing, China), to PCR amplify 16S rDNA using universal primers 27F/1492R (Wang et al. 2017). Also, S. maltophilia 23S rDNA specific primers SM1/SM4 (Whitby et al. 2000) were used for PCR amplification to confirm the species. 16S rDNA sequence analysis showed that SM 2-5 (GenBank Accession No. MW555227), SM 2-13 (GenBank Accession No. MW555228), and SM 2-14 (GenBank Accession No. MW555229) shared the highest identity (>99.9%) with the S. maltophilia strains (GenBank Accession No. MT323142, MH669295, MN826555). Furthermore, 23S rDNA sequence analysis of SM 2-5 (GenBank Accession No. MZ707732), SM 2-13 (GenBank Accession No. MZ645941) and SM 2-14 (GenBank Accession No. MZ707733) revealed their high identity (>99.8%) with the S. maltophilia species. 16S and 23S rDNA phylogenetic analysis (Mega6.06) using the neighbor-joining (NJ) method with 1,000 bootstrap replicates revealed the three strains clustering with the other S. maltophilia strains. Therefore, based on morphology, metabolic profile, and sequence analysis, the three strains were identified as Stenotrophomonas maltophilia. To test pathogenicity, the strains were grown in the nutrient broth (NB) medium for 48h at 28°C until bacterial suspension reached to OD600≈1.0 (2.0×109CFU/mL). Then, healthy roots of one-year-old Sanqi plants, pre-washed with sterilized water and -poked with a sterilized needle, were soaked in bacterial suspension (2.0×109CFU/mL) of the three strains separately for inoculation 10min. Sterilized water treatment was used as a control. Subsequently, bacteria-inoculated plants were planted in sterile soil pots and cultured in a greenhouse at 28°C with shading rate of 70%. Each treatment group included 3 plants with 3 replicates. Ten days post inoculation, symptoms similar to the ones in natural conditions were observed in the bacteria-inoculated plants. Based on the disease index (Li et al. 2020), we found that among the three strains, SM 2-13 displayed the highest virulence, while no symptoms were observed in the control plants. The same bacterial strains were re-isolated from these inoculated roots and identified by the methods described above. Previous studies showed that some Stenotrophomonas species cause plant diseases such as rice white stripe (Singh et al. 2001), strawberry leaf black spot (Wang et al. 2017), Cyclobalanopsis patelliformis leaf spot (Bian et al. 2020), and Jatropha curcas L. seed borne and stem necrosis (Wang et al. 2018). To our knowledge, this is the first report confirming Stenotrophomonas maltophilia causing root soft rot of Panax notoginseng in China.

First report of wild tomato mosaic virus infecting chilli pepper in China.

Chilli pepper is an important economic crop and virus diseases are constraints on its production. In 2018, disease surveys were conducted at a 15-ha chilli pepper plantation in Dehong, southwest of Yunnan Province, China. Throughout the chilli pepper growing season from March to September, pepper plants developed three different virus-like symptoms on leaves, including mosaic, yellow mottle and shrinkage (Fig. S1). Based on observation of virus-like symptomatic phenotypes, the field surveys indicated that the disease incidence ranged from 30% in March to a peak 100% in July, resulting in a significant loss of pepper fruit from 30 to 100% depending on plot of the field. Potyvirus-like filamentous particles, around 11*760 nm, were observed under electron microscopy in the sap of symptomatic leaves (Fig. S1). To further determine the viral species in these samples, total RNA was extracted from three symptomatic samples using a Trans ZolUp Plus RNA Kit (Trans Gene, Beijing, China). Complementary DNA (cDNA) was synthesized using oligo (dT) and M-MLV reverse transcriptase (Promega, Madison, Wisconsin, USA) according to the manufacturer's instructions, and the polymerase chain reaction (PCR) was performed using degenerate primers specific to genus Potyvirus targeting HC-Pro region (HPFor: 5-TGYGAYAAYCARYTIGAYIIIAAYG-3; HPRev: 5-GAICCRWAIGARTCIAIIACRTG-3) (Ha et al. 2008) under the following conditions: an initial denaturation at 94°C for 4min, 30 cycles of denaturation at 94°C for 30 s, annealing at 56°C for 30 s, extension at 72°C for 30s, and a 10min final extension at 72°C. An expected 683-bp DNA fragment was amplified and cloned into the pMD 18-T Vector (Takara, Japan) for sequencing. Sequence analysis using BLAST revealed that the amplicons of phenotype I (Fig. S1a) shared highest nucleotide identity (85.6%) with wild tomato mosaic virus (WTMV) isolate from Vietnam (GenBank no. DQ851495) while the amplicons of phenotype III (Fig. S1c) showed the highest nucleotide identity (93%) with chilli veinal mottle virus (ChiVMV) isolate from Sichuan, China. (GenBank no. MK405594). Amplicons of phenotype II included both sequence of above WTMV and ChiVMV, indicating co-infection of phenotype II (Fig. S1b). Phenotype I sample was used for mechanical inoculation on chilli pepper as described previously (Yang et al.2013). After ten days, virus-like symptoms similar to phenotype I were observed on leaves, and WTMV infection, but not ChiVMV infection, was confirmed by RT-PCR tests on inoculated pepper plants (Fig. S1 e, f). To further ascertain the incidence of these two viruses in the field, primers WT-F: 5'-GTTGTTGAATGTGGTTTAGTT-3' and WT-R: 5'-AGATGTGCTTTGGAAGCGACC-3' were designed based on the WTMV sequence (GenBank no. DQ851495) to amplify a 476 bp product, and primers Ch-F/Ch-R (Ch-F: 5'-AAAGAAGAACAAGCGACAGAA-3', Ch-R: 5'-CATCACGCAAATATTCAAAGC-3') were designed based on ChiVMV sequence (GenBank no. MK405594.1) to amplify a 332 bp product. RT-PCR was conducted on 31 field-collected samples, and amplicons of expected sizes, 476bp and 332bp, corresponding to WTMV and ChiVMV, respectively, were obtained and sequenced to verify their identity. The results (Fig. S2) showed that 71% (22/31) of the samples tested positive for WTMV, 90% (28/31) tested positive for ChiVMV, and 65% (20/31) were co-infected with the two viruses. The WTMV was first reported infecting wild tomatoes in Vietnam in 2008 (Ha et al. 2008), and later reported in China in Nicotiana tabacum (Sun et al. 2015), Solanum nigrum (Zhang et al. 2019), and wild eggplant (Zhang et al. 2014). To our knowledge, this is the first report of WTMV infection on chilli pepper under natural conditions. Our study revealed that the chilli pepper disease in Dehong was caused by single or co-infection of WTMV and ChiVMV. It is necessary to find effective methods to control these two viruses.

Transgenerational effects of BDE-209 on male reproduction in F3 offspring rats.

Decabromodiphenyl ether (BDE-209), a congener of polybrominated diphenyl ethers, is a commonly used brominated flame retardant and a known endocrine disrupting chemical (EDC). Knowledge about the effects of prenatal BDE-209 exposure on male reproduction and whether transgenerational effects occur in subsequent generations are scant. Therefore, in this study, we tested the hypothesis that prenatal exposure to BDE-209 disrupted sperm function in the F1, F2, and F3 generations of male rats. Pregnant Sprague-Dawley rats were treated by gavage from gestation day 0 to birth with 5 mg BDE-209/kg/day. This treatment was based on the lowest-observed-adverse-effect level for DNA damage to sperm in male offspring. On postnatal day 84 for all generations, epididymal sperm counts, motility, morphology, reactive oxygen species generation, sperm chromatin DNA structure integrity, testicular DNA content in spermatogenesis, and serum testosterone levels were assessed. DNA methyltransferase (Dnmts) mRNA expression and methyl-CpG binding domain sequencing were also examined to analyze DNA methylation status in the F3 generation. In the F1 generation, prenatal exposure to BDE-209 disrupted body weight, decreased anogenital distance (AGD), sperm count, and motility; and increased bent tail rates of sperm. In the F2 generation, exposure to BDE-209 decreased AGD, sperm count, normal morphology rates, Dnmt1 expression, and increased Dnmt3a expression. In the F3 generation, BDE-209 exposure decreased AGD and normal sperm morphology, disrupted testicular elongated spermatid and round spermatid rates, reduced serum testosterone levels, and inhibited the mRNA expression of Dnmt1 and Dnmt3b. Compared with the control group, there existed 215 differentially hyper-methylated and 83 hypo-methylated genes in the BDE-209 group. BDE-209 is an EDC to disrupt the male reproduction from F1 to F3. BDE-209-induced changes in sperm function and hyper- or hypo-DNA methylation in the F3 generation might therefore explain the possible mechanism underlying BDE-209-mediated epigenetic transgenerational effects on the male reproductive system.

Stereodivergent Synthesis of Lankacyclinol and Its C2/C18-Congeners Enabled by a Bioinspired Mannich Reaction.

Lankacidin-group antibiotics are complex polyketides typically with a synthetically challenging 17-membered carbocyclic ring. Herein we evolved an alternative palladium-catalyzed coupling-based strategy for constructing this structural moiety. After assembling the two advanced fragments under basic conditions in a biphasic system, of the four possible Mannich adducts, two separable adducts bearing identical C2-stereochemistries were formed in high combined yields, and the ratio of them can be altered by changing the reaction conditions from dichloromethane and 23 °C (18R/18S, 1.5:1) to toluene and 100 °C (18R/18S, 1:3.5). Subsequent base-promoted decarboxylation at lower temperatures unexpectedly favored the formation of the 2,18-anti product, which is less accessible via the reaction carried out on known macrocyclic substrates. All four biosynthetically related C2/C18-isomeric lankacyclinols can be smoothly yielded after Stille macrocyclization, followed by global desilylation. The antimycobacterial activity of the synthetic lankacyclinols and several macrolatonic congeners were preliminarily evaluated.

Landscape of Lankacidin Biomimetic Synthesis: Structural Revisions and Biogenetic Implications.

In this report, a unified biomimetic approach to all known macrocyclic lankacidins is presented. By taking advantage of the thermolysis of N,O-acetal to generate the requisite N-acyl-1-azahexatriene species, we eventually realized the biomimetic Mannich macrocyclization, from which all of the macrocyclic lankacidins can be conquered by orchestrated desilylation. The reassignments of the reported structures of isolankacidinol (7 to 10) and the discovery of a recently isolated "lankacyclinol" found to be in fact 2,18-bis-epi-lankacyclinol (72) unraveled the previously underappreciated chemical diversity exhibited by the enzymatic macrocyclization. In addition, the facile elimination/decarboxylation/protonation process for the depletion of C1 under basic conditions resembling a physiological environment may implicate more undiscovered natural products with variable C2/C18 stereochemistries (i.e., 62, 73, and 75). The notable aspect provided by a biomimetic strategy is significantly reducing the step count compared with the two previous entries to macrocyclic lankacidins.

Postulated Biogenesis-Guided Total Synthesis and Structural Revision of 2,18-seco-Lankacidinol A.

The macrocyclic structure of 2,18-seco-lankacidinol A, a newly isolated antitumor antibiotic, has been revised on the basis of a concise modular synthesis inspired by a reconsidered biosynthetic proposal. Notable features include (1) an acid-promoted intramolecular transacetalization of a N-lactoyl-O-methyl-N,O-acetal to construct the 4-oxazolidinone ring and (2) late-stage ß-keto imide aldolizations that give rise to facile, stereodivergent access to all lactonic diastereomers.

DUSP19 mediates spinal cord injury-induced apoptosis and inflammation in mouse primary microglia cells via the NF-kB signaling pathway.

Objective: Spinal cord injury (SCI) is a common injury that seriously threatens human health. NF-κB may be involved in the secondary injury of SCI that is mediated by inflammation and aggravates damage. Our study was aimed to investigate the role of NF-κB signaling in DUSP19-mediated cleaved Caspase-3 expression and the release of inflammatory factors in vivo and in vitro.Materials and Methods: DUSP19 mRNA expression and the content of IL-6 and IL-8 in patients with traumatic SCI (TSCI) were measured by real-time PCR and ELISA, respectively. The levels of p-NF-κBp65, NF-κBp65 and cleaved Caspase-3 expression and the concentrations of IL-6 and IL-8 were measured by western blotting and ELISA, respectively.Results: Patients with TSCI showed lower DUSP19 expression and higher concentration of IL-6 and IL-8 compared with healthy controls. DUSP19 overexpression inhibited p-NF-κBp65 level, cleaved Caspase-3 expression, and production of IL-8 and IL-6 in the mice induced by TSCI. DUSP19 silencing increased p-NF-κBp65 level, cleaved Caspase-3 expression, and concentration of IL-6 and IL-8 in mouse primary microglia cells. DUSP19 overexpression had an inverse effect. Importantly, DUSP19 silencing and overexpression mediated p-NF-κBp65 level, cleaved Caspase-3 expression, and concentration of IL-6 and IL-8 in mouse primary microglia cells were reversed by NF-κB inhibitor pyrrolidine dithiocarbamate (PDTC) and NF-κB activator 12-myristate 13-acetate (PMA), respectively.Conclusion: These results suggested that DUSP19-mediated SCI-induced apoptosis and inflammation via NF-κB signaling and might therefore serve as a potential therapeutic target for SCI.

Stereoconfining macrocyclizations in the total synthesis of natural products.

Covering: selected examples in the past three decades (up to 2018) The challenging structures and often potent biological activities of naturally occurring macrocycles have attracted much attention among the synthetic community. In a typical retrosynthetic disconnection, commonly used macrocyclization tactics, including macrolactonization, macrolactamization, ring-closing metathesis, olefination, and metal-mediated cross-coupling reactions, are invariably based on linear substrates in which all of the stereogenic centers have already been set forth. Macrocyclizations with the simultaneous installation of the requisite stereogenic centers can be advantageous with respect to a broader substrate spectrum as well as a usually higher overall synthetic efficiency. However, achieving predictably high levels of stereocontrol remains a formidable challenge. In this review, we discuss representative examples of those "nonclassic" macrocyclization strategies in the context of natural product total synthesis. Different types of macrocycle-forming methods are summarized, with a particular focus on the sense of diastereoinduction imparted through the transition-state macrocyclic ring architecture (≥12-membered) or the catalyst.

Enhanced recovery care versus traditional care following laminoplasty: A retrospective case-cohort study.

Enhanced recovery after surgery (ERAS) has been shown to shorten length of hospital stay and reduce perioperative complications in many types of surgeries. However, there has been a paucity of research examining the application of ERAS to major spinal surgery. The current study was performed to compare complications and hospital stay after laminoplasty between an ERAS group and a traditional care group.The ERAS group included 114 patients who underwent laminoplasty managed with an ERAS protocol between January 2016 and June 2017. The traditional care group included 110 patients, who received traditional perioperative care between November 2014 and December 2015. Postoperative hospital stay (POPH), physiological function, postoperative visual analogue scale (VAS) pain score, and postoperative complications were compared between the 2 groups.The mean POPH was significantly shorter in the ERAS group than traditional care group (5.75 ±â€Š2.46 vs. 7.67 ±â€Š3.45 d, P < .001). ERAS protocol significantly promoted postoperative early food-taking (8.45 ±â€Š2.94 h vs 21.64 ±â€Š2.66 h, P < .001), reduced the first time of assisted walking (30.79 ±â€Š14.45 vs. 65.24 ±â€Š25.34 h, P < .001), postoperative time of indwelling urinary catheters (24.76 ±â€Š12.34 vs. 53.61 ±â€Š18.16 h, P < .001), and wound drainage catheters (43.92 ±â€Š7.14 vs. 48.85 ±â€Š10.10 h, P < .001), as compared with the traditional care group. Pain control was better in the ERAS group than traditional care group in terms of mean VAS score (2.72 ±â€Š0.46 vs. 3.35 ±â€Š0.46, P < .001) and mean maximum VAS score (3.76 ±â€Š1.12 vs. 4.35 ±â€Š1.15, P < .001) in 3 days after surgery. The morbidity rate was 21.05% (24 of 114 patients) in the ERAS group and 20.90% (23 of 110 patients) in the control group (P = .75).The ERAS protocol is both safe and feasible for patients undergoing laminoplasty, and can decrease the length of postoperative hospitalization without increasing the risk of complications.

Computer Simulation of Two-level Pedicle Subtraction Osteotomy for Severe Thoracolumbar Kyphosis in Ankylosing Spondylitis.

BACKGROUND: Advanced ankylosing spondylitis is often associated with thoracolumbar kyphosis, resulting in an abnormal spinopelvic balance and pelvic morphology. Different osteotomy techniques have been used to correct AS deformities, unfortunnaly, not all AS patients can gain spinal sagittal balance and good horizontal vision after osteotomy. MATERIALS AND METHODS: Fourteen consecutive AS patients with severe thoracolumbar kyphosis who were treated with two-level PSO were studied retrospectively. All were male with a mean age of 34.9 ± 9.6 years. The followup ranged from 1-5 years. Preoperative computer simulations using the Surgimap Spinal software were performed for all patients, and the osteotomy level and angle determined from the computer simulation were used surgically. Spinal sagittal parameters were measured preoperatively, after the computer simulation, and postoperatively and included thoracic kyphosis (TK), lumbar lordosis (LL), sagittal vertical axis (SVA), pelvic incidence, pelvic tilt (PT), and sacral slope (SS). The level of correlation between the computer simulation and postoperative parameters was evaluated, and the differences between preoperative and postoperative parameters were compared. The visual analog scale (VAS) for back pain and clinical outcome was also assessed. RESULTS: Six cases underwent PSO at L1 and L3, five cases at L2 and T12, and three cases at L3 and T12. TK was corrected from 57.8 ± 15.2° preoperatively to 45.3 ± 7.7° postoperatively (P < 0.05), LL from 9.3 ± 17.5° to -52.3 ± 3.9° (P < 0.001), SVA from 154.5 ± 36.7 to 37.8 ± 8.4 mm (P < 0.001), PT from 43.3 ± 6.1° to 18.0 ± 0.9° (P < 0.001), and SS from 0.8 ± 7.0° to 26.5 ± 10.6° (P < 0.001). The LL, VAS, and PT of the simulated two-level PSO were highly consistent with, or almost the same as, the postoperative parameters. The correlations between the computer simulations and postoperative parameters were significant. The VAS decreased significantly from 6.1 ± 1.9 to 2.0 ± 1.1 (P < 0.001). In terms of clinical outcome, 10 cases were graded "excellent" and 4 cases were graded "good." CONCLUSION: Two-level PSO using a preoperative computer simulation is a feasible, safe, and effective technique for the treatment of severe thoracolumbar kyphosis in AS patients with normal cervical motion.

Biomimetic Synthesis of Lankacidin Antibiotics.

We devised short syntheses of lankacidinol and lankacyclinol that feature biomimetic Mannich macrocyclization. The modular construction of the carbon framework of these compounds is amenable to rapid structural diversification for the development of antibiotic and antitumor agents.

Clinical outcome of laminoplasty for cervical ossification of the posterior longitudinal ligament with K-line (-) in the neck neutral position but K-line (+) in the neck extension position: A retrospective observational study.

Patients with cervical ossification of the posterior longitudinal ligament (OPLL) who are K-line (-) are thought to have poor clinical outcomes after laminoplasty. The aim of this study is to compare the clinical results of patients with OPLL who were K-line (-) in the neck neutral position but K-line (+) in the neck extension position (NEP group) with patients with OPLL who were K-line (+) in the neck neutral position (NNP group).Retrospectively, 42 patients who underwent cervical laminoplasty for OPLL by our surgical group during 2012 and 2013 were reviewed and were followed for at least 2 years. The patients were divided into 2 groups according to K-line status. Standing plain radiographs of the cervical spine were obtained pre- and postoperatively. Cervical spine alignment parameters included the C2-7 Cobb angle and range of motion (ROM) measured on lateral radiographs. Clinical evaluation included pre- and postoperative JOA, NDI, and VAS scores.Ten patients were classified in the NEP group, and 32 patients were classified in the NNP group. Preoperatively, the OPLL involved segments were 4.10 ±â€Š1.66 in the NEP group and 2.53 ±â€Š1.16 in the NNP group (P = .005). The canal-occupying ratios were 58.40 ±â€Š11.11% in the NEP group and 29.08 ±â€Š11.38% in the NNP group (P < .001). The mean Cobb angle of both the groups had not changed significantly at the last follow-up. The mean cervical ROM of both the groups had decreased at the last follow-up. The mean JOA score of the NEP group improved significantly from 9.70 ±â€Š2.16 to 12.50 ±â€Š2.27 (P = .014). The mean JOA score of the NNP group improved significantly from 11.91 ±â€Š1.69 to 14.93 ±â€Š1.58 (P < .001). The mean JOA recovery rate was 32.71 ±â€Š40.45% in the NEP group and 59.00 ±â€Š33.80% in the NNP group (P = .036). The NDI scores of both groups were significantly decreased, and the VAS scores of both groups had not changed significantly at the last follow-up.Laminoplasty is a relatively effective and safe procedure for patients with K-line (-) in the neck neutral position but K-line (+) in the neck extension position. Instead of anterior surgery, we recommend laminoplasty for those patients with OPLL extending to 3 or more segments.

[Optimization of ultrasonic extraction process for Xiaoqinglong granules by Box-Behnken in condition of medium scale].

This paper is to investigate the optimization conditions of ultrasonic technique for extraction process of Xiaoqinglong granules in medium scale. First of all, single factor experiment was used to determine the overall impact tendency and range of each factor； secondly, Box-Behnken method was used for optimization and detecting the content of paeoniflorin, ephedrine hydrochloride, glycyrrhizic acid of the liquid medicine. Their respective extraction rate was calculated and the comprehensive evaluation was carried out. The results were used as the evaluation basis for the efficacy of Xiaoqinglong granules ultrasonic extraction. The test results showed that the optimum extraction process of Xiaoqinglong granules by ultrasonic extraction was under the following conditions: ultrasonic power 600 W, liquid-solid ratio 10∶1, extraction for 31 min. Under this condition, the predicted value of extraction rate for Xiaoqinglong granules was 85.90%, and the test value was 85.87%. The mathematical model(P<0.01) established in this paper was significant, and can be used for the analysis and prediction of the ultrasonic extraction process of Xiaoqinglong granules.

[Application of microwave technology in extraction process of Guizhi Fuling capsule].

In this paper, optimization of the conditions of microwave technique in extraction process of Guizhi Fuling capsule in the condition of a pilot scale was carried out. First of all, through the single factor experiment investigation of various factors, the overall impact tendency and range of each factor were determined. Secondly, L9 (3(4)) orthogonal test optimization was used, and the contents of gallic acid in liquid, paeoniflorin, benzoic acid, cinnamic acid, benzoyl paeoniflorin, amygdalin of the liquid medicine were detected. The extraction rate and comprehensive evaluation were calculated with the extraction effect, as the judgment basis. Theoptimum extraction process of Guizhi Fuling capsule by microwave technology was as follows: the ratio of liquid to solid was 6: 1 added to drinking water, the microwave power was 6 kW, extraction time was 20 min for 3 times. The process of the three batch of amplification through verification, the results are stable, and compared with conventional water extraction has the advantages of energy saving, time saving, high efficiency advantages. The above results show the optimum extracting technology of high efficiency, stable and feasible.