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1.
Plant Biotechnol J ; 22(6): 1669-1680, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38450899

RESUMO

The exploitation of heterosis to integrate parental advantages is one of the fastest and most efficient ways of rice breeding. The genomic architecture of heterosis suggests that the grain yield is strongly correlated with the accumulation of numerous rare superior alleles with positive dominance. However, the improvements in yield of hybrid rice have shown a slowdown or even plateaued due to the limited availability of complementary superior alleles. In this study, we achieved a considerable increase in grain yield of restorer lines by inducing an alternative splicing event in a heterosis gene OsMADS1 through CRISPR-Cas9, which accounted for approximately 34.1%-47.5% of yield advantage over their corresponding inbred rice cultivars. To achieve a higher yield in hybrid rice, we crossed the gene-edited restorer parents harbouring OsMADS1GW3p6 with the sterile lines to develop new rice hybrids. In two-line hybrid rice Guang-liang-you 676 (GLY676), the yield of modified hybrids carrying the homozygous heterosis gene OsMADS1GW3p6 significantly exceeded that of the original hybrids with heterozygous OsMADS1. Similarly, the gene-modified F1 hybrids with heterozygous OsMADS1GW3p6 increased grain yield by over 3.4% compared to the three-line hybrid rice Quan-you-si-miao (QYSM) with the homozygous genotype of OsMADS1. Our study highlighted the great potential in increasing the grain yield of hybrid rice by pyramiding a single heterosis gene via CRISPR-Cas9. Furthermore, these results demonstrated that the incomplete dominance of heterosis genes played a major role in yield-related heterosis and provided a promising strategy for breeding higher-yielding rice varieties above what is currently achievable.


Assuntos
Genes Dominantes , Vigor Híbrido , Oryza , Melhoramento Vegetal , Oryza/genética , Oryza/crescimento & desenvolvimento , Vigor Híbrido/genética , Melhoramento Vegetal/métodos , Sistemas CRISPR-Cas , Edição de Genes/métodos , Hibridização Genética , Plantas Geneticamente Modificadas/genética , Genes de Plantas/genética , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
2.
Org Biomol Chem ; 22(4): 645-681, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38180073

RESUMO

Organochalcogen compounds are prevalent in numerous natural products, pharmaceuticals, agrochemicals, polymers, biological molecules and synthetic intermediates. Direct chalcogenation of C-H bonds has evolved as a step- and atom-economical method for the synthesis of chalcogen-bearing compounds. Nevertheless, direct C-H chalcogenation severely lags behind C-C, C-N and C-O bond formations. Moreover, compared with the C-H monochalcogenation, reports of selective mono-/dichalcogenation and exclusive dichalcogenation of C-H bonds are relatively scarce. The past decade has witnessed significant advancements in selective mono-/dichalcogenation and exclusive dichalcogenation of various C(sp2)-H and C(sp3)-H bonds via transition-metal-catalyzed/mediated, photocatalytic, electrochemical or metal-free approaches. In light of the significance of both mono- and dichalcogen-containing compounds in various fields of chemical science and the critical issue of chemoselectivity in organic synthesis, the present review systematically summarizes the advances in these research fields, with a special focus on elucidating scopes and mechanistic aspects. Moreover, the synthetic limitations, applications of some of these processes, the current challenges and our own perspectives on these highly active research fields are also discussed. Based on the substrate types and C-H bonds being chalcogenated, the present review is organized into four sections: (1) transition-metal-catalyzed/mediated chelation-assisted selective C-H mono-/dichalcogenation or exclusive dichalcogenation of (hetero)arenes; (2) directing group-free selective C-H mono-/dichalcogenation or exclusive dichalcogenation of electron-rich (hetero)arenes; (3) C(sp3)-H dichalcogenation; (4) dichalcogenation of both C(sp2)-H and C(sp3)-H bonds. We believe the present review will serve as an invaluable resource for future innovations and drug discovery.

3.
Sleep Breath ; 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38858326

RESUMO

PURPOSE: Patients with obstructive sleep apnea syndrome (OSAS) frequently experience cognitive dysfunction, which may be connected to chronic intermittent hypoxia (CIH). Insulin-like growth factor-1 (IGF-1) is thought to be closely associated with cognitive function, but its role in cognitive impairment caused by OSAS is unclear. The purpose of this study was to investigate the potential protective effect of IGF-1 on cognitive impairment in OSAS rats. METHODS: Healthy male SD rats (n = 40) were randomly assigned into four groups: control group, CIH group, NS + CIH group, and IGF-1 + CIH group. All experimental rats except for those in the control group were exposed to intermittent hypoxic (IH) environments for 8 h per day over 28 days. Prior to daily exposure to IH, rats in the IGF-1 + CIH group received subcutaneous injections of IGF-1. The Morris water maze test was conducted on all experimental rats. Brain tissue testing methods included Enzyme-Linked Immunosorbent Assay, Hematoxylin and eosin staining, Immunohistochemistry, and Western blotting. RESULTS: The rat model of OSAS was successfully established following exposure to CIH and exhibited significant cognitive impairment. However, daily subcutaneous injections of IGF-1 partially restored the impaired cognitive function in OSAS rats. Compared with the control group, there was a significant decrease in the expression levels of IGF-1, p-IGF-IR, and SYP in the CIH group; however, these expression levels increased significantly in the IGF-I + CIH group. CONCLUSION: In OSAS rats, IGF-1 enhances learning memory; this effect may be linked to increased p-IGF-1R and SYP protein production in the hippocampus.

4.
Chem Biol Interact ; 390: 110854, 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38161044

RESUMO

This study aimed to explore effects of microRNA (miR)-143 on the proliferation, apoptosis, and cytokine secretion in astrocytes after spinal cord injury (SCI). After gain- and loss-of-function assays and transforming growth factor (TGF)-ß stimulation in astrocytes, the cell viability, proliferation, and apoptosis were examined. The expression of miR-143, SIRT2, and PLAUR and levels of astrocyte-related glial fibrillary acidic protein (GFAP), Vimentin, chondroitin sulfate proteoglycan (CSPG), and connective tissue growth factor (CTGF) were also measured. The binding relationship between miR-143 and SIRT2 was assessed, as well as the correlation of PLAUR with SIRT2. In established SCI rat models, the locomotion function and astrocyte hyperplasia were detected. The TGF-ß stimulation decreased miR-143 but increased SIRT2 expression in astrocytes. Mechanistically, miR-143 negatively targeted SIRT2 and SIRT2 down-regulation inhibited the H3K27 deacetylation of PLAUR promoter to increase PLAUR expression. miR-143 up-regulation inhibited TGF-ß stimulated-proliferation, promoted cell apoptosis, and reduced GFAP, Vimentin, CSPG, and CTGF expression in astrocytes, which was counterweighed by SIRT2 overexpression. SIRT2 silencing reduced the proliferation and GFAP, Vimentin, CSPG, and CTGF expression while augmenting the apoptosis in TGF-ß stimulated astrocytes, which was abrogated by PLAUR silencing. The injection of miR-143 agomir improved the locomotion function and reduced the astrocyte hyperplasia in SCI rats, which was reversed by silencing PLAUR. miR-143 targeted SIRT2 to affect PLAUR expression via the regulation of histone acetylation, which repressed the astrocyte activation in vivo and in vitro to improve the locomotion function in SCI rats.


Assuntos
MicroRNAs , Traumatismos da Medula Espinal , Animais , Ratos , Acetilação , Astrócitos , Histonas/metabolismo , Hiperplasia/metabolismo , MicroRNAs/metabolismo , Sirtuína 2/genética , Sirtuína 2/metabolismo , Medula Espinal/metabolismo , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/patologia , Fator de Crescimento Transformador beta/metabolismo , Vimentina/genética , Vimentina/metabolismo
5.
Hum Cell ; 37(2): 451-464, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38167752

RESUMO

This study aims to explore the functions and mechanisms of long noncoding RNA small nucleolar RNA host gene 5 (SNHG5) in chronic constriction injury (CCI)-induced neuropathic pain (NP). An NP rat model was established using the CCI method and the NP severity was evaluated by paw withdrawal threshold (PWT) and paw withdrawal latency (PWL). The expression of SNHG5, CDK9, and SCN9A was quantified in rat dorsal root ganglion, in addition to the detections of apoptosis, pathological changes, neuron number, and the co-localization of Nav1.7 and cleaved caspase-3 with NeuN. In ND7/23 cells, the apoptosis and lactate dehydrogenase concentration were assessed, as well as the relationship between SNHG5, CDK9, and SCN9A. In the dorsal root ganglion of CCI-treated rats, SNHG5 and SCN9A were upregulated and downregulation of SNHG5 suppressed SCN9A expression, increased the PWT and PWL, blocked neuroinflammation and neuronal apoptosis, and alleviated NP. Mechanistically, SNHG5 recruited CDK9 to enhance SCN9A-encoded Nav1.7 expression and promoted peripheral neuronal apoptosis and injury. In addition, SCN9A overexpression nullified the alleviative effects of SNHG5 deficiency on NP and neuron loss in CCI rats. In conclusion, SNHG5 promotes SCN9A-encoded Nav1.7 expression by recruiting CDK9, thereby facilitating neuron loss and NP after spinal nerve injury, which may offer a promising target for the management of NP.


Assuntos
MicroRNAs , Neuralgia , RNA Longo não Codificante , Animais , Ratos , MicroRNAs/genética , Neuralgia/genética , Ratos Sprague-Dawley , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA Nucleolar Pequeno , Nervos Espinhais/metabolismo , Quinase 9 Dependente de Ciclina/metabolismo
6.
Org Lett ; 26(15): 3140-3144, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38563571

RESUMO

Carbonylative multifunctionalization of alkenes is an efficient approach to introduce multiple functional groups into one molecule from easily available materials. Herein, we developed an iron-catalyzed radical relay carbonylative cyclization of alkenes with acetamides. Various α-tetralones can be constructed in moderate yields from readily available substrates with an earth-abundant iron salt as the catalyst.

7.
Front Chem ; 12: 1434996, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39176075

RESUMO

The work in this paper incorporated printed circuit board (PCB) technology into micro-direct methanol fuel cells (µDMFCs) and conjectured and verified the performance degradation factors of PCB current collectors in µDMFCs by testing different designed configuration µDMFCs. The experiment results showed that all kinds of PCB coating can benefit from the porous stainless-steel plates covering to a great extent. At the end of 48 h discharging, µDMFCs with porous stainless-steel plates between MEA and PCB coating achieved higher performance than those of the direct contacting series. It can be inferred from various types of experimental data that because of stainless-steel porous plate isolating, the impact of corrosion on the surface of the PCB electrode plate was reduced to a certain extent. The corrosion of the electrode plate was slowed down in the µDMFC discharging as a result of the passivation behavior on the iron surface and a decrease in corrosion current. Consequently, the attenuation of the PCB performance was delayed. The conclusion of this work explores a practical direction to enhance the cost-effectiveness of fuel cells, promoting the large-scale application of DMFCs in the future.

8.
Heliyon ; 10(7): e28630, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38596092

RESUMO

Nontuberculous mycobacteria associated intracranial infection is a rare disease that mainly occurs in HIV-infected patients. The disease has a poor prognosis. The authors report a case of non-tuberculous mycobacterial meningoencephalitis in a non-AIDS patient, but long history of poorly controlled type 2 diabetes mellitus. A 55-year-old, right-handed, male patient presented with an 8-day history of fever, episodes of severe headache with signs of meningeal irritation. MRI showed hyperintensities/contrast enhancement in the visual pathways, basal ganglia sellar region and leptomeninges. No etiological diagnosis was reached until metagenomic next-generation sequencing (mNGS) was used, showing the presence of Mycobacterium avium. The patient was cured with aggressive antimycobacterial therapy. The authors discuss the clinical manifestations and drug therapy of nontuberculous mycobacteria-related intracranial infections by reviewing relevant literature. As meningoencephalitis by Mycobacterium avium has a high mortality an early diagnosis and appropriate therapeutic interventions are warranted. For this reason, the use of mNGS can be helpful to avoid therapeutic delay.

9.
Chem Asian J ; 19(9): e202400124, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38421239

RESUMO

In light of the important biological activities and widespread applications of organic disulfides, dithiocarbamates, xanthates, thiocarbamates and thiocarbonates, the continual persuit of efficient methods for their synthesis remains crucial. Traditionally, the preparation of such compounds heavily relied on intricate multi-step syntheses and the use of highly prefunctionalized starting materials. Over the past two decades, the direct sulfuration of C-H bonds has evolved into a straightforward, atom- and step-economical method for the preparation of organosulfur compounds. This review aims to provide an up-to-date discussion on direct C-H disulfuration, dithiocarbamation, xanthylation, thiocarbamation and thiocarbonation, with a special focus on describing scopes and mechanistic aspects. Moreover, the synthetic limitations and applications of some of these methodologies, along with the key unsolved challenges to be addressed in the future are also discussed. The majority of examples covered in this review are accomplished via metal-free, photochemical or electrochemical approaches, which are in alignment with the overraching objectives of green and sustainable chemistry. This comprehensive review aims to consolidate recent advancements, providing valuable insights into the dynamic landscape of efficient and sustainable synthetic strategies for these crucial classes of organosulfur compounds.

10.
Mater Horiz ; 11(9): 2191-2205, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38410914

RESUMO

Liquid-free ionic conductive elastomers (ICEs) are ideal materials for constructing flexible electronic devices by avoiding the limitations of liquid components. However, developing all-solid-state ionic conductors with high mechanical strength, high ionic conductivity, excellent healing, and recyclability remains a great challenge. Herein, a series of liquid-free polyurethane-based ICEs with a double dynamic crosslinked structure are reported. As a result of interactions between multiple dynamic bonds (multi-level hydrogen bonds, disulfide bonds, and dynamic D-A bonds) and lithium-oxygen bonds, the optimal ICE exhibited a high mechanical strength (1.18 MPa), excellent ionic conductivity (0.14 mS cm-1), desirable healing capacity (healing efficiency >95%), and recyclability. A multi-functional wearable sensor based on the novel ICE enabled real-time and rapid detection of various human activities and enabled recognizing writing signals and encrypted information transmission. A triboelectric nanogenerator based on the novel ICE exhibited an excellent open-circuit voltage of 464 V, a short-circuit current of 16 µA, a transferred charge of 50 nC, and a power density of 720 mW m-2, enabling powering of small-scale electronic products. This study provides a feasible strategy for designing flexible sensor products and healing, self-powered devices, with promising prospects for application in soft ionic electronics.

11.
Adv Mater ; 36(25): e2401689, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38552182

RESUMO

Bottlebrush polymers (BB) have emerged as compelling candidates for biosystems to face tribological challenges, including friction and wear. This study provides a comprehensive assessment of an engineered triblock BB polymer's affinity, cell toxicity, lubrication, and wear protection in both in vitro and in vivo settings, focusing on applications for conditions like osteoarthritis and dry eye syndrome. Results show that the designed polymer rapidly adheres to various surfaces (e.g., cartilage, eye, and contact lens), forming a robust, biocompatible layer for surface lubrication and protection. The tribological performance and biocompatibility are further enhanced in the presence of hyaluronic acid (HA) both in vitro and in vivo. The exceptional lubrication performance and favorable interaction with HA position the synthesized triblock polymer as a promising candidate for innovative treatments addressing deficiencies in bio-lubricant systems.


Assuntos
Fricção , Ácido Hialurônico , Polímeros , Animais , Ácido Hialurônico/química , Polímeros/química , Polímeros/farmacologia , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Camundongos , Humanos , Lubrificação , Propriedades de Superfície , Lubrificantes/química , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia
12.
Science ; 384(6698): 901-906, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38781358

RESUMO

Rice (Oryza sativa) serves as a staple food for more than one-third of the global population. However, its journey from a wild gathered food to domestication remains enigmatic, sparking ongoing debates in the biological and anthropological fields. Here, we present evidence of rice phytoliths sampled from two archaeological sites in China, Shangshan and Hehuashan, near the lower reaches of the Yangtze River. We demonstrate the growth of wild rice at least 100,000 years before present, its initial exploitation as a gathered resource at about 24,000 years before present, its predomestication cultivation at about 13,000 years before present, and eventually its domestication at about 11,000 years before present. These developmental stages illuminate a protracted process of rice domestication in East Asia and extend the continuous records of cereal evolution beyond the Fertile Crescent.


Assuntos
Domesticação , Oryza , Arqueologia , China , Produtos Agrícolas
13.
Electron. j. biotechnol ; 15(4): 9-9, July 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-646959

RESUMO

In the present study, a novel plant transformation system for Doritaenopsis and Phalaenopsis has been developed. The pollen-mediated activation tagging system was established by artificial pollination. The pollens, co-cultured with Agrobacterium tumefaciens strain EHA105 harbouring an activation tagging vector (pTAG-8), were used for pollination. In order to optimize the transformation efficiency, several factors (concentration of A. tumefaciens, concentration of acetosyringone during co-cultivation and the duration of co-cultivation) known to influence Agrobacterium-mediated DNA transfer were examined. A concentration of 0.5-1 x 10(8) CFU/ml for A. tumefaciens, 0.1 mM acetosyringone, and 6 hrs of co-culture period were found to be the optimal condition for high transformation efficiency. Integration of T-DNA into the genome of putative transgenic plants was confirmed by PCR and DNA blot analyses. Single copy of the transgene was observed in all transgenic plants analyzed. Most of the transgenic plants had a morphologically normal phenotype and the overall capsule formation efficiency was similar to control plant. Our results showed a new approach of genetic transformation in orchids and this method can be employed for genetic improvement of the orchids.


Assuntos
Agrobacterium tumefaciens , Orchidaceae/genética , Polinização , Elementos de DNA Transponíveis/genética , Reação em Cadeia da Polimerase , Transformação Genética
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