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1.
Front Neurol ; 13: 915188, 2022.
Article in English | MEDLINE | ID: mdl-36570459

ABSTRACT

Introduction: Neurological impairment during spinal deformity surgery is the most serious possible complication. When confronting intraoperative neurophysiological monitoring alerts, various surgical management methods such as the release of implants and decompression of the spinal cord are always performed. Transvertebral transposition of the spinal cord is rarely performed, and its role in the management of acute paraplegia is seldom reported. Case description: The authors present two patients with kyphoscoliosis who experienced neurological deficits and abnormal neurological monitoring intraoperatively or post-operatively that were detected during correction surgery. Acute paraplegia was confirmed by a wake-up test. Subsequent spinal cord transposition was performed. Intraoperative neurophysiological monitoring motor-evoked potentials (MEPs) and somatosensory-evoked potentials (SEPs) were performed to detect the changes during the process. After transvertebral transposition of the spinal cord, the MEPs and SEPs were significantly improved in both patients during surgery. The spinal cord function was restored post-operatively and recovered to normal at the final follow-up in two patients. Conclusion: This case demonstrated that instead of decreasing the correction ratio of kyphoscoliosis, transvertebral transposition of the spinal cord under intraoperative neurophysiological monitoring may be an alternative therapeutic strategy for acute spinal cord dysfunction caused by deformity correction surgeries.

2.
Org Lett ; 24(31): 5791-5796, 2022 Aug 12.
Article in English | MEDLINE | ID: mdl-35916599

ABSTRACT

A novel visible-light-mediated difluoroalkylation of 1-(allyloxy)-2-(1-arylvinyl)benzenes and 1-(1-arylvinyl)-2-(vinyloxy)benzenes for the synthesis of bis-difluoroalkylated benzoxepines and 2H-chromenes is developed. This method features mild reaction conditions, good regioselectivity, a wide substrate scope, good functional-group compatibility, and late-stage modification. Preliminary mechanistic studies reveal that the generation of the CF2CO2Et radical is more prone to reaction with the double bond of the aryl group.

3.
Sci China Life Sci ; 65(11): 2148-2161, 2022 11.
Article in English | MEDLINE | ID: mdl-35960419

ABSTRACT

Lesion mutants can be valuable tools to reveal the interactions between genetic factors and environmental signals and to improve grain production. Here we identified a rice (Oryza sativa) mutant, lesion spotleaf1 (lsl1), which produces necrotic leaf lesions throughout its life cycle. LSL1 encodes a protein of unknown function and belongs to a grass-specific clade. The lesion phenotype of the lsl1 mutant was sharply induced by shading, and its detached leaves incubated in 6-benzylamino purine similarly formed lesions in the dark. In addition, the lsl1 mutant exhibited reactive oxygen species accumulation and cell death. The terminal deoxynucleotidyl transferase dUTP nick end-labeling (TUNEL) and comet assays revealed that the lsl1 mutant contained severe DNA damage, resulting in reduced grain yield and quality. RNA sequencing, gene expression, and protein activity analyses indicate that LSL1 is required for chloroplast function. Furthermore, LSL1 interacts with PsaD and PAP10 to form a regulatory module that functions in chlorophyll synthesis and chloroplast development to maintain redox balance. Our results reveal that LSL1 maintains chloroplast structure, redox homeostasis, and DNA stability, and plays important roles in the interaction between genetic factors and environmental signals and in regulating grain size and quality.


Subject(s)
Oryza , Oryza/genetics , Edible Grain/genetics , Chloroplasts , Cell Death , Plant Leaves/genetics
4.
J Org Chem ; 87(15): 10277-10284, 2022 Aug 05.
Article in English | MEDLINE | ID: mdl-35791911

ABSTRACT

Visible-light-induced radical cascade acylation/cyclization/aromatization of N-propargyl aromatic amines and acyl oxime esters for the construction of 3-acylated quinolines is developed. This approach uses acyl oxime esters as the precursor of acyl radicals as well as acylation reagents, Eosin Y as the photocatalyst, and acetonitrile as the solvent, providing a convenient route toward 3-acylated quinolines via the C-C bond cleavage of acyl oxime esters.

5.
Orthop Surg ; 14(3): 621-627, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35156309

ABSTRACT

BACKGROUND: Tendon calcification is a common disease, and it could happen in the tendons of the shoulder, wrist, etc. However, tendon calcification in the superior and inferior gemellus is rare, and in this region is likely to be misdiagnosed. CASE PRESENTATION: Here, our case report first reported a 53-year-old female patient with an unusual case of calcific tendinitis of the gemellus superior and gemellus inferior muscles. The patient presented with severe pain in the right hip and lower extremities, not relieved using nonsteroidal anti-inflammatory drugs (NSAIDs). The preoperative physical examination indicated an abnormality in the hip joint. Preoperative imaging confirmed the results of the physical examination and showed a right hip lesion. We did not make a definite diagnosis preoperatively but considered that the patient might have an osteochondroma. However, surgical findings indicated that the lesion was not in the hip capsule on subsequent arthroscopic surgery, which suggested that the preoperative diagnosis might be wrong. We opened the posterior capsule and found a "toothpaste-like" lesion in the superior and inferior gemellus muscles' tendon. We thought this might be the calcified tendon. Then the arthroscopic surgery was finished to remove the lesion, and the removed tissue was sent to the pathology department for pathological examination. The pathological report confirmed the diagnosis of the calcified tendon. Postoperative follow-up was conducted. The effect of the operation was noticeable. Postoperative symptoms were relieved. CONCLUSIONS: Calcification of the tendons of the superior and inferior gemellus muscles can be easily misdiagnosed, and the disease can be treated minimally with arthroscopy.


Subject(s)
Tendinopathy , Arthroscopy/methods , Female , Hip , Humans , Middle Aged , Tendinopathy/surgery , Tendons/surgery , Wrist Joint
6.
Chem Commun (Camb) ; 58(14): 2335-2338, 2022 Feb 15.
Article in English | MEDLINE | ID: mdl-35079757

ABSTRACT

A palladium-catalyzed radical cascade cyanoalkylsulfonylation/cyclization of 3-arylethynyl-[1,1'-biphenyl]-2-carbonitriles with DABCO·(SO2)2 and cyclobutanone oxime esters via cleavage of a C-C single bond and insertion of SO2 was described. A series of cyanoalkylsulfone-containing cyclopenta[gh]phenanthridines were obtained in moderate-to-good yields, thus featuring mild reaction conditions, a broad substrate scope, and a high functional group tolerance.

7.
J Org Chem ; 86(21): 15253-15262, 2021 Nov 05.
Article in English | MEDLINE | ID: mdl-34643392

ABSTRACT

A visible-light-induced cascade cyanoalkylsulfonylation/cyclization/aromatization of N-propargyl aromatic amines with K2S2O5 and cyclobutanone oxime esters for the construction of cyanoalkylsulfonylated quinolines is developed. This cascade transformation features mild reaction conditions, a broad substrate scope, and excellent functional group compatibility, providing a convenient route toward cyanoalkylsulfonylated quinolines via the formation of a C-C bond and two C-S bonds in one step.

8.
Plant J ; 105(4): 942-956, 2021 02.
Article in English | MEDLINE | ID: mdl-33190327

ABSTRACT

Lesion-mimic mutants (LMMs) provide a valuable tool to reveal the molecular mechanisms determining programmed cell death (PCD) in plants. Despite intensive research, the mechanisms behind PCD and the formation of lesions in various LMMs still remain to be elucidated. Here, we identified a rice (Oryza sativa) LMM, early lesion leaf 1 (ell1), cloned the causal gene by map-based cloning, and verified this by complementation. ELL1 encodes a cytochrome P450 monooxygenase, and the ELL1 protein was located in the endoplasmic reticulum. The ell1 mutant exhibited decreased chlorophyll contents, serious chloroplast degradation, upregulated expression of chloroplast degradation-related genes, and attenuated photosynthetic protein activity, indicating that ELL1 is involved in chloroplast development. RNA sequencing analysis showed that genes related to oxygen binding were differentially expressed in ell1 and wild-type plants; histochemistry and paraffin sectioning results indicated that hydrogen peroxide (H2 O2 ) and callose accumulated in the ell1 leaves, and the cell structure around the lesions was severely damaged, which indicated that reactive oxygen species (ROS) accumulated and cell death occurred in the mutant. TUNEL staining and comet experiments revealed that severe DNA degradation and abnormal PCD occurred in the ell1 mutants, which implied that excessive ROS accumulation may induce DNA damage and ROS-mediated cell death in the mutant. Additionally, lesion initiation in the ell1 mutant was light dependent and temperature sensitive. Our findings revealed that ELL1 affects chloroplast development or function, and that loss of ELL1 function induces ROS accumulation and lesion formation in rice.


Subject(s)
Cytochrome P-450 Enzyme System/metabolism , Oryza/metabolism , Plant Proteins/metabolism , Reactive Oxygen Species/metabolism , Cell Death , Chloroplasts/enzymology , Chloroplasts/metabolism , Cloning, Molecular , Cytochrome P-450 Enzyme System/genetics , Cytochrome P-450 Enzyme System/physiology , Gene Expression Regulation, Plant , Hydrogen Peroxide/metabolism , Oryza/enzymology , Oryza/genetics , Phylogeny , Plant Leaves/enzymology , Plant Leaves/metabolism , Plant Proteins/genetics , Plant Proteins/physiology
10.
Plant Physiol ; 184(1): 251-265, 2020 09.
Article in English | MEDLINE | ID: mdl-32680975

ABSTRACT

Rice (Oryza sativa) spikelets have a unique inflorescence structure, and the mechanisms regulating their development are not yet fully understood. Moreover, approaches to manipulate spikelet development have the potential to increase grain yield. In this study, we identified and characterized a recessive spikelet mutant, namely more floret1 (mof1). The mof1 mutant has a delayed transition from the spikelet to the floral meristem, inducing the formation of extra lemma-like and palea-like organs. In addition, the main body of the palea was reduced, and the sterile lemma was enlarged and partially acquired hull (lemma and/or palea) identity. We used map-based cloning to identify the MOF1 locus and confirmed our identification by complementation and by generating new mof1 alleles using CRISPR-Cas9 gene editing. MOF1 encodes a MYB domain protein with the typical ethylene response factor-associated amphiphilic repression motifs, is expressed in all organs and tissues, and has a strong repression effect. MOF1 localizes to the nucleus and interacts with TOPLESS-RELATED PROTEINs to possibly repress the expression of downstream target genes. Taken together, our results reveal that MOF1 plays an important role in the regulation of organ identity and spikelet determinacy in rice.


Subject(s)
Flowers/metabolism , Oryza/metabolism , Plant Proteins/metabolism , Transcription Factors/metabolism , Alleles , Flowers/genetics , Gene Expression Regulation, Plant/genetics , Gene Expression Regulation, Plant/physiology , Inflorescence/genetics , Inflorescence/metabolism , Meristem/genetics , Meristem/metabolism , Oryza/genetics , Plant Proteins/genetics , Transcription Factors/genetics
11.
Sci China Life Sci ; 63(2): 228-238, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31919631

ABSTRACT

The palea and lemma are floral organ structures unique to grasses; these structures form the hull and directly affect grain size and quality. However, the molecular mechanisms controlling the development of the hull are not well understood. In this study, we characterized the rice (Oryza sativa) abnormal flower and grain1 (afg1) mutant, a new allele of OsMADS6. Similar to previously characterized osmads6 alleles, in the afg1 floret, the palea lost its marginal region and acquired the lemma identity. However, in contrast to other osmads6 alleles, the afg1 mutant showed altered grain size and grain quality, with decreased total starch and amylose contents, and increased protein and soluble sugar contents. The analysis of transcriptional activity suggested that AFG1 is a transcriptional activator and may affect grain size by regulating the expression levels of several genes related to cell expansion and proliferation in the afg1 mutant. These results revealed that AFG1 plays an important role in determining palea identity and affecting grain yield and quality in rice.


Subject(s)
Edible Grain/genetics , Flowers/genetics , MADS Domain Proteins/genetics , Oryza/genetics , Plant Proteins/genetics , Alleles , Amino Acid Sequence , Amylose/genetics , Chromosome Mapping , Cloning, Molecular , Gene Expression Regulation, Plant , Genes, Plant , MADS Domain Proteins/metabolism , Mutation/genetics , Oryza/growth & development , Phenotype , Plant Proteins/metabolism , Plants, Genetically Modified , Starch/genetics , Sugars/metabolism , Transcription, Genetic
12.
Sci Bull (Beijing) ; 65(9): 753-764, 2020 May 15.
Article in English | MEDLINE | ID: mdl-36659109

ABSTRACT

Rice (Oryza sativa) spikelets are a unique inflorescence structure and their development directly determines grain size and yield. Although many genes related to spikelet development have been reported, the molecular mechanisms underlying this process have not been fully elucidated. In this study, we identified a new recessive rice mutant, lacking rudimentary glume 1 (lrg1). The lrg1 spikelets only formed one rudimentary glume, which, along with the sterile lemmas, was homeotically transformed into lemma-like organs and acquired lemma identity. The transition from the spikelet to the floral meristem was delayed in the lrg1 mutant, resulting in the formation of an ectopic lemma-like organ between the sterile lemma and the terminal floret. In addition, we found that the abnormal lrg1 grain phenotype resulted from the alteration of cell numbers and the hull size. LRG1 encodes a ZOS4-06-C2H2 zinc-finger protein with the typical EAR motifs, and is expressed in all organs and tissues. LRG1 localizes to the nucleus and can interact with the TOPLESS-RELATED PROTEINs (TPRs) to repress the expressions of their downstream target genes. Taken together, our results reveal that LRG1 plays an important role in the regulation of spikelet organ identity and grain size.

13.
Plant Biotechnol J ; 18(1): 119-128, 2020 01.
Article in English | MEDLINE | ID: mdl-31141272

ABSTRACT

Heading date 1 (Hd1) is an important gene for the regulation of flowering in rice, but its variation in major cultivated rice varieties, and the effect of this variation on yield and quality, remains unknown. In this study, we selected 123 major rice varieties cultivated in China from 1936 to 2009 to analyse the relationship between the Hd1 alleles and yield-related traits. Among these varieties, 19 haplotypes were detected in Hd1, including two major haplotypes (H8 and H13) in the japonica group and three major haplotypes (H14, H15 and H16) in the indica group. Analysis of allele frequencies showed that the secondary branch number was the major aimed for Chinese indica breeding. In the five major haplotypes, SNP316 (C-T) was the only difference between the two major japonica haplotypes, and SNP495 (C-G) and SNP614 (G-A) are the major SNPs in the three indica haplotypes. Association analysis showed that H16 is the most preponderant allele in modern cultivated Chinese indica varieties. Backcrossing this allele into the japonica variety Chunjiang06 improved yield without decreasing grain quality. Therefore, our analysis offers a new strategy for utilizing these preponderant alleles to improve yield and quality of japonica varieties for cultivation in the southern areas of China.


Subject(s)
Oryza/genetics , Plant Breeding , Alleles , China , Gene Frequency , Haplotypes , Polymorphism, Single Nucleotide
14.
Plant J ; 100(4): 813-824, 2019 11.
Article in English | MEDLINE | ID: mdl-31357245

ABSTRACT

The palea and lemma (hull) are grass-specific organs, and determine grain size and quality. In the study, AH2 encodes a MYB domain protein, and functions in the development of hull and grain. Mutation of AH2 produces smaller grains and alters grain quality including decreased amylose content and gel consistency, and increased protein content. Meantime, part of the hull lost the outer silicified cells, and induces a transformation of the outer rough epidermis to inner smooth epidermis cells, and the body of the palea was reduced in the ah2 mutant. We confirmed the function of AH2 by complementation, CRISPR-Cas9, and cytological and molecular tests. Additionally, AH2, as a repressor, repress transcription of the downstream genes. Our results revealed that AH2 plays an important role in the determination of hull epidermis development, palea identity, and grain size.


Subject(s)
Oryza/growth & development , Plant Proteins/metabolism , Seeds/growth & development , Cloning, Molecular , Flowers/growth & development , Gene Expression Regulation, Plant , Mutation , Oryza/physiology , Plant Epidermis/growth & development , Plant Proteins/genetics , Plants, Genetically Modified , Transcription Factors/genetics , Transcription Factors/metabolism
16.
J Exp Bot ; 69(20): 4853-4866, 2018 09 14.
Article in English | MEDLINE | ID: mdl-30032251

ABSTRACT

In grass, the spikelet is a unique inflorescence structure that directly determines grain yield. Despite a great deal of research, the molecular mechanisms behind spikelet development are not fully understood. In the study, FZP encodes an ERF domain protein, and functions in grain size and sterile lemma identity. Mutation of FZP causes smaller grains and degenerated sterile lemmas. The small fzp-12 grains were caused by a reduction in cell number and size in the hulls. Interestingly, the sterile lemma underwent a homeotic transformation into a rudimentary glume in the fzp-12 and fzp-13 mutants, whereas the sterile lemma underwent a homeotic transformation into a lemma in FZP over-expressing plants, suggesting that FZP specifically determines the sterile lemma identity. We confirmed the function of FZP by complementation, CRISPR-Cas9 gene editing, and cytological and molecular tests. Additionally, FZP interacts specifically with the GCC-box and DRE motifs, and may be involved in regulation of the downstream genes. Our results revealed that FZP plays a vital role in the regulation of grain size, and first provides clear evidence in support of the hypothesis that the lemma, rudimentary glume, and sterile lemma are homologous organs.


Subject(s)
Edible Grain/growth & development , Flowers/growth & development , Oryza/genetics , Plant Proteins/genetics , Edible Grain/genetics , Flowers/genetics , Gene Expression Regulation, Plant , Mutation , Oryza/growth & development , Plant Proteins/metabolism
18.
Front Plant Sci ; 7: 1853, 2016.
Article in English | MEDLINE | ID: mdl-28018389

ABSTRACT

Grasses produce seeds on spikelets, a unique type of inflorescence. Despite the importance of grass crops for food, the genetic mechanisms that control spikelet development remain poorly understood. In this study, we used m34-z, a new mutant allele of the rice (Oryza sativa) E-class gene OsMADS34, to examine OsMADS34 function in determining the identities of glumes (rudimentary glume and sterile lemma) and grain size. In the m34-z mutant, both the rudimentary glume and sterile lemma were homeotically converted to the lemma-like organ and acquired the lemma identity, suggesting that OsMADS34 plays important roles in the development of glumes. In the m34-z mutant, most of the grains from the secondary panicle branches (spb) were decreased in size, compared with grains from wild-type, but no differences were observed in the grains from the primary panicle branches. The amylose content and gel consistency, and a seed-setting rate from the spb were reduced in the m34-z mutant. Interesting, transcriptional activity analysis revealed that OsMADS34 protein was a transcription repressor and it may influence grain yield by suppressing the expressions of BG1, GW8, GW2, and GL7 in the m34-z mutant. These findings revealed that OsMADS34 largely affects grain yield by affecting the size of grains from the secondary branches.

19.
J Integr Plant Biol ; 58(6): 529-39, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26486996

ABSTRACT

Moderate plant height and successful establishment of reproductive organs play pivotal roles in rice grain production. The molecular mechanism that controls the two aspects remains unclear in rice. In the present study, we characterized a rice gene, ABNORMAL FLOWER AND DWARF1 (AFD1) that determined plant height, floral development and grain yield. The afd1 mutant showed variable defects including the dwarfism, long panicle, low seed setting and reduced grain yield. In addition, abnormal floral organs were also observed in the afd1 mutant including slender and thick hulls, and hull-like lodicules. AFD1 encoded a DUF640 domain protein and was expressed in all tested tissues and organs. Subcellular localization showed AFD1-green fluorescent fusion protein (GFP) was localized in the nucleus. Meantime, our results suggested that AFD1 regulated the expression of cell division and expansion related genes.


Subject(s)
Edible Grain/growth & development , Edible Grain/metabolism , Flowers/metabolism , Oryza/growth & development , Oryza/genetics , Plant Proteins/metabolism , Plants, Genetically Modified/growth & development , Plants, Genetically Modified/metabolism , Edible Grain/genetics , Flowers/genetics , Gene Expression Regulation, Plant/genetics , Gene Expression Regulation, Plant/physiology , Oryza/metabolism , Plant Proteins/genetics , Plants, Genetically Modified/genetics
20.
Nanoscale ; 7(10): 4461-7, 2015 Mar 14.
Article in English | MEDLINE | ID: mdl-25683086

ABSTRACT

The piezotronic effect, which utilizes the piezopotential to engineer the interface characteristics, has been widely exploited to design novel functional device or to optimize the device performance, which is intimately related to the carrier concentration. Here, by constructing a general Schottky diode, the piezotronic effect dependence on the carrier concentration was investigated systematically using ultraviolet (UV) illumination. Scanning Kelvin Probe Microscopy was employed to quantify the carrier concentration in ZnO nanorods under UV illumination. The results showed that the carrier concentration increases with increasing light intensity and an average value of up to 5.6 × 10(18) cm(-3) under 1.2 mW cm(-2) light illumination was obtained. Furthermore, with increasing UV light intensity, an increasingly imperceptible variation in the current-voltage characteristics under strain was observed, which finally disappeared under 1.2 mW cm(-2) light illumination. This phenomenon was attributed to the weakened modulation ability of the piezopotential due to the strengthened screening effect. In addition, the gradual disappearing in the barrier also contributed to the gradual disappearance of the piezotronic effect. This study provides an in-depth understanding of piezotronics, which could be extended to other piezoelectric devices and guide the design and optimization of piezotronic and even piezophototronic devices.

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