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1.
Plant Dis ; 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38803070

RESUMEN

Polygonatum kingianum is a Chinese herbal medicine that belongs to the genus Polygonatum of the family Liliaceae. In June 2023, Polygonatum kingianum Coll. et Hemsl. in nurseries in Qujing, Yunnan Province, China, showed irregular brown spots on the leaves, whole leaf necrosis, and plant death in serious cases, with an incidence of 10-20% (Fig. S1). To identify the pathogens of P. kingianum, six diseased samples were collected from nurseries with 0.6 acre. These diseased sample leaves were soaked in 0.1% HgCl2 for 1 min and 75% ethanol for 2 min and then rinsed thrice with sterile water. Treated leaves were cut into small pieces (5×5 mm) and cultured on potato dextrose agar (PDA) for five days at 28°C. Total thirteen fungal strains were isolated from PDA medium. The nuclear ribosomal internal transcribed spacer of ribosomal DNA (ITS rDNA) region of these 13 strains was amplified by polymerase chain reaction (PCR) using universal primers ITSI/ITS4 (White et al. 1990). Sequencing and BLAST of the ITS region on NCBI showed that 11 out of 13 fungal strains belonged to the genus Alternaria, with an identity ≥99%. We selected one of the Alternaria strains, HJ-A1, for further study. The HJ-A1 colony appeared grayish brown white-to-gray with a flocculent texture on the front side and a dark gray underside on the PDA medium (Fig. S1). The conidiophores appeared brown, either single or branched, and produced numerous short conidial chains. The conidia were obclavate to obpyriform or ellipsoid in shape and contained 1-4 transverse septa and 0-2 oblique septa. The conidial diameter was 27.30µm in length and 12.27µm in width. (Fig. S1). To further determine the species of HJA1, the genomic DNA of HJ-A1 was extracted using the Lysis Buffer for PCR (AG, Hunan, China). Four Alternaria genomic DNA regions including the ITS, translation elongation factor 1-α gene (TEF1-α), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and Alternaria major allergen gene (Alt a1) were amplified by PCR using the primers as previously reported (Woudenberg et al. 2013, Hong et al. 2005). Sequence analysis revealed that the ITS (484bp) of HJ-A1 (NCBI No. PP082633), TEF1-α (267bp) of HJ-A1 (NCBI No. PP419893), GAPDH (582bp) of HJ-A1 (NCBI No. PP419892), and Alt a1 (522bp) of HJ-A1 (NCBI No. PP228046) shared the highest identity with A. alternata respectively (99≥%). A maximum likelihood phylogenetic tree was constructed with the combined sequence data sets of ITS, GAPDH, TEF, and Alt a1 using MEGA 7. The results showed that HJ-A1 strain clustered with A. alternate (Fig. S2). The pathogenicity of HJ-A1 was tested according to Koch's postulates by inoculating HJ-A1 conidia suspension (2×105 conidia/mL) into leaves of 1-year-old P. kingianum, with sterile water as a control. Each treatment group included 3 plants with 3 replicates. The tested plants were planted in a phytotron at 28℃ and 90% humidity. Three days after inoculation, symptoms similar to those under natural conditions were observed in the HJ-A1-inoculated plants, whereas no symptoms were observed in the control plants (Fig. S1). The same fungal strains were re-isolated from inoculated leaves and identified by morphologically and sequence of ITS. Previous studies showed that Alternaria alternata funji cause many plant diseases, such as fig fruit rot (Latinovic N et al. 2014),daylily leaf spot (Huang D et al. 2022), fruit blight on sesame (Cheng H et al. 2021),leaf spot of Cynanchum atratum Bunge (Sun H et al. 2021) and so on. To our knowledge, this is the first report of A. alternata causing P. kingianum leaf spot in China. The discovery of this pathogen will help to guide the protection and control of P. kingianum disease.

2.
J Org Chem ; 89(11): 7355-7365, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38727521

RESUMEN

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.

3.
Front Neurol ; 15: 1352949, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38469591

RESUMEN

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.

4.
ACS Cent Sci ; 9(1): 84-92, 2023 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-36712486

RESUMEN

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.

5.
Ying Yong Sheng Tai Xue Bao ; 33(9): 2363-2370, 2022 Sep.
Artículo en Chino | MEDLINE | ID: mdl-36131651

RESUMEN

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.


Asunto(s)
Banco de Semillas , Suelo , Ecosistema , Bosques , Nitrógeno , Fósforo , Semillas/fisiología , Suelo/química
6.
Chinese Journal of Surgery ; (12): 69-78, 2022.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-935582

RESUMEN

Objective: To investigate the role of minimally invasive crenel lateral lumbar interbody fusion (CLIF) in the decision of fusion level in posterior correction for severe adult degenerative scoliosis. Methods: This is a prospective study.Patients with level Ⅴ and Ⅵ of Lenke-Silva classification who were treated at Department of Orthopedics,the Second Affiliated Hospital, School of Medicine, Zhejiang University from June 2016 to March 2019 were included.First,the enrolled patients completed the preoperative clinical and imaging examination,the Lenke-Silva classification was evaluated,the surgical segments in first-stage CLIF was determined and the fusion segments required for single-stage posterior correction was predicted.After the first-stage CLIF,patients received reassessment of Lenke-Silva classification and global coronal and sagittal balance.Patients were divided into two groups:the effective group (level of Lenke-Silva classification decreased) and the ineffective group (level of Lenke-Silva classification unchanged).Second-stage posterior surgery was performed based on the results of reassessments.The fusion segment,Cobb angle,parameters of global coronal and sagittal plane,visual analogue pain score (VAS) and Oswestry disability index (ODI) were compared between the two groups preoperatively,after first-stage CLIF,second-stage posterior fixation and at the final follow-up.The potential factors associated with the decrease of the level of Lenke-Silva classification were recorded and compared between the two groups.Independent sample t test,repeated measure analysis of variance,rank sum test,χ2 test or Fisher exact method were used to compare the difference among groups. Results: Fifty-four patients were enrolled,including 8 males and 46 females,aged (68.8±5.8) years (range:56 to 77 years).Preoperatively,26 patients were classified as level Ⅴ by Lenke-Silva classification,28 cases were grade Ⅵ.CLIF was performed in 194 segments,with 114 segments(58.8%) receiving anterior column realignment (ACR) and 15 segments(7.7%) using hyperlordotic cages.After first-stage CLIF,22 patients with level Ⅴ and 10 patients with Ⅵ of Lenke-Silva classification decreased and were classified into effective group.The level of the remaining 4 patients with level Ⅴ and 18 patients with grade Ⅵ unchanged and were classified into ineffective group.Preoperatively,the apical vertebrae was below L1 in all 32 patients of effective group and 18 (81.8%,18/22) patients of ineffective group.The difference was statistically significant (P=0.023).There were 7 (31.8%,7/22) patients had continuous osteophyte in front of the intervertebral space in ineffective group,while none patient had continuous osteophyte in front of the intervertebral space in effective group,and the difference was statistically significant (P=0.001).In first-stage CLIF,more intraoperative ACR(71.2% vs.39.5%,χ²=20.660,P<0.01)and hyperlordotic cage (12.7% vs.0,P=0.001) were used in the effective group,while there was less severe cage subsidence after the operation (5.9% vs.15.8%,χ²=4.793,P=0.029) in effective group.After first-stage CLIF,there was no difference in the Cobb angle between the two groups.While,lumbar lordosis (LL) in effective group (34.0±8.3)° was greater than that of the ineffective group (25.5±9.7)° (t=3.478,P=0.001),and the difference between the pelvic incidence (PI) and LL in effective group (15.7±4.6)°was significantly smaller than ineffective group(20.0±10.8)° (t=-2.129,P=0.038).The posterior fusion levels was less,the rate of fusion to thoracic spine region and the actual fusion segment was less than that of single-stage posterior correction in effective group (all P<0.01).All patients were follow-up for 24 to 45 months.There was no significant difference in radiological and clinical results between the two groups after first-,second-stage surgery and at the final follow-up (all P>0.05). Conclusions: First-stage CLIF decreased the Lenke-Silva classification of some patients with severe degenerative scoliosis.Combined with the reassessment of Lenke-Silva classification and global coronal and sagittal plane,it helps to accurately determine the fusion segment.Decrease of Lenke-Silva classification is associated with the preoperative level of apical vertebrae,continuous osteophytes in front of the intervertebral space,intraoperative use of ACR and hyperlordotic cage and the degree of cage subsidence postoperatively.


Asunto(s)
Adulto , Anciano , Animales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Vértebras Lumbares/cirugía , Estudios Prospectivos , Estudios Retrospectivos , Escoliosis/cirugía , Fusión Vertebral , Resultado del Tratamiento
7.
Orthop Traumatol Surg Res ; 107(7): 103033, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34358711

RESUMEN

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.


Asunto(s)
Vértebras Lumbares , Fusión Vertebral , Humanos , Incidencia , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Estudios Retrospectivos , Factores de Riesgo , Fusión Vertebral/métodos
8.
Plant Dis ; 2021 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-34410858

RESUMEN

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.

9.
Acc Chem Res ; 54(17): 3438-3451, 2021 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-34383479

RESUMEN

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.


Asunto(s)
Antibacterianos/química , Antibacterianos/farmacología , Macrólidos/química , Macrólidos/farmacología , Animales , Materiales Biomiméticos , Humanos , Macrólidos/síntesis química , Estructura Molecular
10.
Plant Dis ; 2021 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-33926200

RESUMEN

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.

11.
Chemosphere ; 272: 129829, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35534961

RESUMEN

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.


Asunto(s)
Disruptores Endocrinos , Efectos Tardíos de la Exposición Prenatal , Animales , ADN , Disruptores Endocrinos/farmacología , Femenino , Genitales Masculinos , Éteres Difenilos Halogenados/toxicidad , Humanos , Masculino , Embarazo , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Efectos Tardíos de la Exposición Prenatal/metabolismo , ARN Mensajero , Ratas , Ratas Sprague-Dawley , Reproducción , Espermatogénesis , Testosterona
12.
J Org Chem ; 86(16): 10991-11005, 2021 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-33289391

RESUMEN

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.


Asunto(s)
Antibacterianos , Paladio , Antibacterianos/farmacología , Tolueno
13.
J Org Chem ; 85(21): 13818-13836, 2020 11 06.
Artículo en Inglés | MEDLINE | ID: mdl-32985194

RESUMEN

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.


Asunto(s)
Biomimética , Macrólidos
14.
Org Lett ; 22(10): 3785-3788, 2020 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-32329349

RESUMEN

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.


Asunto(s)
Aldehídos/química , Antibióticos Antineoplásicos/síntesis química , Lactonas/química , Macrólidos/síntesis química , Antibióticos Antineoplásicos/química , Macrólidos/química , Estructura Molecular
15.
Neurol Res ; 42(1): 31-38, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31813339

RESUMEN

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.


Asunto(s)
Apoptosis/fisiología , Fosfatasas de Especificidad Dual/biosíntesis , Microglía/metabolismo , FN-kappa B/metabolismo , Traumatismos de la Médula Espinal/metabolismo , Animales , Células Cultivadas , Fosfatasas de Especificidad Dual/antagonistas & inhibidores , Fosfatasas de Especificidad Dual/genética , Humanos , Inflamación/genética , Inflamación/metabolismo , Inflamación/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Microglía/patología , Estudios Prospectivos , Distribución Aleatoria , Transducción de Señal/fisiología , Traumatismos de la Médula Espinal/genética , Traumatismos de la Médula Espinal/patología
16.
Nat Prod Rep ; 36(11): 1546-1575, 2019 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-30758359

RESUMEN

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.


Asunto(s)
Productos Biológicos/síntesis química , Alquenos/química , Productos Biológicos/química , Catálisis , Ciclización , Estructura Molecular , Compuestos Organometálicos/química
17.
Medicine (Baltimore) ; 97(48): e13195, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30508899

RESUMEN

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.


Asunto(s)
Vértebras Cervicales/cirugía , Laminoplastia/métodos , Atención Perioperativa/métodos , Anciano , Catéteres/estadística & datos numéricos , Protocolos Clínicos , Femenino , Humanos , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Manejo del Dolor/métodos , Educación del Paciente como Asunto , Complicaciones Posoperatorias/epidemiología , Estudios Retrospectivos
18.
Indian J Orthop ; 51(6): 666-671, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29200482

RESUMEN

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.

19.
J Am Chem Soc ; 139(37): 12939-12942, 2017 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-28853876

RESUMEN

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.


Asunto(s)
Antibacterianos/síntesis química , Materiales Biomiméticos/síntesis química , Macrólidos/síntesis química , Antibacterianos/química , Materiales Biomiméticos/química , Macrólidos/química , Estructura Molecular
20.
Medicine (Baltimore) ; 96(22): e6964, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28562546

RESUMEN

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.


Asunto(s)
Vértebras Cervicales/diagnóstico por imagen , Vértebras Cervicales/cirugía , Laminoplastia , Osificación del Ligamento Longitudinal Posterior/diagnóstico por imagen , Osificación del Ligamento Longitudinal Posterior/cirugía , Femenino , Estudios de Seguimiento , Humanos , Cifosis/diagnóstico por imagen , Cifosis/cirugía , Lordosis/diagnóstico por imagen , Lordosis/cirugía , Masculino , Persona de Mediana Edad , Cuello , Osificación del Ligamento Longitudinal Posterior/clasificación , Posicionamiento del Paciente , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
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