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1.
J Hazard Mater ; 432: 128650, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35290892

RESUMO

Toxification metabolism of the chiral triazole fungicide prothioconazole in the environment has attracted an increasing amount of attention. To better understand the fate of prothioconazole in aquatic ecosystems and develop a treatment strategy, the stereoselective toxicity, degradation and bioconcentration of prothioconazole were investigated in water with algae at the enantiomer level. There was remarkable enantioselectivity against Chlorella pyrenoidosa, and the highly toxic S-prothioconazole was preferentially degraded with enantiomer fraction values ranging from 0.5 to 0.74. Metabolism experiment results showed that the parent compound was quickly eliminated driven by biodegradation and abiotic degradation (hydrolysis, photolysis). Fourteen phase I and two phase II metabolites involved in the reactions of hydroxylation, methylation, dechlorinating, desulfuration, dehydration and conjugation were identified, where prothioconazole-desthio was the major metabolite. The highly toxic metabolite prothioconazole-desthio persisted in water and hardly degraded with or without C. pyrenoidosa. Furthermore, the reaction system including 1 mg of cobalt coated in nitrogen doped carbon nanotubes and 0.156 g of peroxymonosulfate was used to eliminate prothioconazole-desthio. Approximately 96% prothioconazole-desthio was eliminated and transformed to low toxicity metabolites. This work provides a strategy for the risk evaluation of prothioconazole in aquatic ecosystems and proposes a workable plan for the elimination of pesticide residues in water.


Assuntos
Chlorella , Fungicidas Industriais , Nanotubos de Carbono , Chlorella/metabolismo , Ecossistema , Fungicidas Industriais/química , Triazóis/química , Água
2.
J Agric Food Chem ; 70(11): 3375-3390, 2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35275483

RESUMO

Breeding low phytic acid (lpa) crops is a strategy that has potential to both improve the nutritional quality of food and feed and contribute to the sustainability of agriculture. Here, we review the lipid-independent and -dependent pathways of phytate synthesis and their regulatory mechanisms in plants. We compare the genetic variation of the phytate concentration and distribution in seeds between dicot and monocot species as well as the associated temporal and spatial expression patterns of the genes involved in phytate synthesis and transport. Quantitative trait loci or significant single nucleotide polymorphisms for the seed phytate concentration have been identified in different plant species by linkage and association mapping, and some genes have been cloned from lpa mutants. We summarize the effects of various lpa mutations on important agronomic traits in crop plants and propose SULTR3;3 and SULTR3;4 as optimal target genes for lpa crop breeding.


Assuntos
Ácido Fítico , Melhoramento Vegetal , Mutação , Ácido Fítico/metabolismo , Locos de Características Quantitativas , Sementes/genética , Sementes/metabolismo
3.
Small ; 18(11): e2104876, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35119209

RESUMO

Lithium (Li) metal is an excellent anode of Li ion batteries because of its high theoretical capacity and the low redox potential compared to other anodes. However, the uncontrollable growth of Li dendrites still incurs serious safety issues and poor electrochemical performances, leading to its limited practical application. An oxygen and boron codoped honeycomb carbon skeleton (OBHcCs) is reported and a stable Li metal-based anode is realized. It can be coated on a copper foil substrate to be used as a current collector for a dendrite-free Li metal anode. OBHcCs effectively reduces the local current density owing to the high surface area and inhibits Li dendrite growth, which is explored by scanning electron microscopy and an X-ray photoelectron spectra depth profile. The abundant lithiophilic oxygen and boron-containing functional groups reduce the potential barrier of nucleation and lead to the homogeneous Li ions flux as confirmed by the density functional theories. Therefore, the Li metal anode based on OBHcCs (OBHcCs@Li) stably runs for 700 h in a symmetric cell with a Li stripping capacity of 1 mAh cm-2 at 1 mA cm-2 . Furthermore, the OBHcCs@Li|LiFePO4 full cell shows a good capacity retention of 84.6% with a high coulombic efficiency of 99.6% at 0.5 C for 500 cycles.

4.
Chem Commun (Camb) ; 58(14): 2307-2310, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-35075462

RESUMO

AlP and SiP2 are promising alloy-type anode materials for lithium-ion batteries (LIBs), owing to their good conductivity, high storage capacity and appropriate working potential. However, they still suffer from rapid capacity decay due to the huge volume expansion and the resultant pulverization. Carbon modification can not only relieve volume changes but also provide a conducting matrix for the active material. Moreover, the charge transfer of the multi-phase composite can be accelerated owing to its electric field at the heterointerface. Hence, a bimetallic phosphide AlP/SiP2@C composite was synthesized for the first time via a facile and scalable high energy ball milling method and applied as an anode material for LIBs. Benefitting from the above combined advantages of the heterostructure and carbon layer protection, the AlP/SiP2@C electrode delivered a high reversible capacity (1482 mA h g-1 at the current density of 0.3 A g-1) and durable lifespan (516 mA h g-1 after 4000 cycles at a current density of 3 A g-1), which are superior to those of the binary AlP@C and SiP2@C composites.

5.
Colloids Surf B Biointerfaces ; 207: 111992, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34391168

RESUMO

Macrophages perform multiple functions in both inflammation and wound healing, and are one of the fore front cells during implant osseointegration that influence subsequent process. Essential trace element modification may effectively modulate titanium implant surface biological properties. In this work, strontium (Sr) incorporated micro/nano rough titanium surfaces (Sr-SLA) was fabricated by hydrothermal treatment, and immunoreaction of macrophages was further investigated. In vitro results revealed that Sr doping inhibited inflammatory response of macrophages, further attenuated the inhibitory effect on following bone marrow derived cells (BMSCs) osteogenic differentiation. The regulation of macrophages by Sr-SLA likely involved ERK signaling pathway. Consistently, the in vivo study showed that compared with titanium surface sand-blasted with large grit and double acid-etched (SLA) implants, Sr-SLA implants could enhance new bone formation accompanied with more alternatively activated M2 macrophages infiltration and less classically activated M1 macrophages infiltration. These results reveal the immunomodulatory ability of Sr-SLA of adjusting the functional status of macrophages through inhibiting M1 polarization while promoting M2 polarization.


Assuntos
Osseointegração , Estrôncio , Macrófagos , Osteogênese , Estrôncio/farmacologia , Propriedades de Superfície , Titânio/farmacologia
6.
J Int Med Res ; 49(5): 3000605211016381, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34024190

RESUMO

Renal arteriovenous malformations (AVMs) are infrequent vascular morphological anomalies. About 20% of AVMs are congenital renal AVMs (CRAVMs). A 53-year-old female patient presented with a 5-day history of gross hematuria and right flank pain. The patient underwent the selective renal arteriography and embolization under local anesthesia. Renal computed tomography angiography (CTA) and digital subtraction angiography (DSA) results showed bleeding of the right renal arteriovenous malformation, both nidus and aneurysm, which indicated that the patient had both cirsoid and cavernosal types of CRAVM. Endovascular management was chosen to treat the patient. The patient was cured and discharged, then followed-up for 3 months. These results show that early identification using radiologic tests is important for diagnosis and treatment of CRAVM.


Assuntos
Malformações Arteriovenosas , Embolização Terapêutica , Malformações Arteriovenosas Intracranianas , Nefropatias , Angiografia Digital , Malformações Arteriovenosas/diagnóstico por imagem , Malformações Arteriovenosas/cirurgia , Feminino , Humanos , Rim/diagnóstico por imagem , Rim/cirurgia , Pessoa de Meia-Idade
7.
J Biomed Mater Res B Appl Biomater ; 109(11): 1754-1767, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33871914

RESUMO

Early infection and peri-implantitis after implant restoration are major reasons for dental implant failure. Implant-associated infections are majorly attributed to biofilm formation. In this study, co-incorporated zinc- (Zn-) and strontium- (Sr-) nanorod coating on sandblasted and acid-etched (SLA) titanium (SLA-Zn/Sr) was fabricated by hydrothermal synthesis. It was aimed at promoting osteogenesis while inhibiting biofilm formation. The nanorod-like particles (φ 30-50 nm) were found to be evenly formed on SLA-Zn/Sr (Zn: 1.49 ± 0.16 wt%; Sr: 21.69 ± 2.74 wt%) that was composed of well-crystallized ZnTiO3 and SrTiO3 phases. With a sufficient interface bonding strength (42.00 ± 3.00 MPa), SLA-Zn/Sr enhanced the corrosion resistance property of titanium. Besides, SLA-Zn/Sr promoted the cellular initial adhesion, proliferation and osteogenic differentiation of rBMSCs in vitro while inhibiting the adhesion of Staphylococcus aureus and Porphyromonas gingivalis . In addition, through down-regulating icaA gene expression, this novel surface reduced the secretion of polysaccharide intercellular adhesion (reduced by 87.9% compared to SLActive) to suppress the S. aureus biofilm formation. We, therefore, propose a new chemical modification on titanium for multifunctional implant material development. Due to the Zn/Sr co-doping in coating, material properties, early osteogenic effect and antibacterial ability of titanium can be simultaneously enhanced, which has the potential to be applied in dental implantation in the future.


Assuntos
Antibacterianos/química , Biofilmes , Células-Tronco Mesenquimais , Nanotubos/química , Porphyromonas gingivalis/fisiologia , Staphylococcus aureus/fisiologia , Estrôncio/química , Titânio/química , Zinco/química , Animais , Masculino , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/microbiologia , Ratos , Ratos Sprague-Dawley , Propriedades de Superfície
8.
Chem Commun (Camb) ; 57(19): 2364-2367, 2021 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-33533779

RESUMO

The Petasis reaction using (1S,2R)-1-amino-2-indanol as the substrate and an activator to construct α- and ß-butadienyl amines in optically pure forms was realized, which are otherwise difficult to prepare. The reactions feature a metal-free nature, broad substrate scope, complete regioselectivities (γ-selectivity of pinacol homoallenyl- and isoprenylboronates), and high to excellent chirality induction (up to >20 : 1 dr). The favored nucleophilic addition across the Si-face of the imine intermediate was explained using DFT calculations of the six-membered chair-like transition state.

9.
World J Surg Oncol ; 19(1): 13, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33441161

RESUMO

BACKGROUND: Colon cancer is a worldwide leading cause of cancer-related mortality, and the prognosis of colon cancer is still needed to be improved. This study aimed to construct a prognostic model for predicting the prognosis of colon cancer. METHODS: The gene expression profile data of colon cancer were obtained from the TCGA, GSE44861, and GSE44076 datasets. The WGCNA module genes and common differentially expressed genes (DEGs) were used to screen out the prognosis-associated DEGs, which were used to construct a prognostic model. The performance of the prognostic model was assessed and validated in the TCGA training and microarray validation sets (GSE38832 and GSE17538). At last, the model and prognosis-associated clinical factors were used for the construction of the nomogram. RESULTS: Five colon cancer-related WGCNA modules (including 1160 genes) and 1153 DEGs between tumor and normal tissues were identified, inclusive of 556 overlapping DEGs. Stepwise Cox regression analyses identified there were 14 prognosis-associated DEGs, of which 12 DEGs were included in the optimized prognostic gene signature. This prognostic model presented a high forecast ability for the prognosis of colon cancer both in the TCGA training dataset and the validation datasets (GSE38832 and GSE17538; AUC > 0.8). In addition, patients' age, T classification, recurrence status, and prognostic risk score were associated with the prognosis of TCGA patients with colon cancer. The nomogram was constructed using the above factors, and the predictive 3- and 5-year survival probabilities had high compliance with the actual survival proportions. CONCLUSIONS: The 12-gene signature prognostic model had a high predictive ability for the prognosis of colon cancer.


Assuntos
Neoplasias do Colo , Biologia Computacional , Biomarcadores Tumorais/genética , Neoplasias do Colo/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Recidiva Local de Neoplasia , Prognóstico
10.
Angew Chem Int Ed Engl ; 59(49): 21986-21990, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32797667

RESUMO

Genetically encoded RNA devices have emerged for various cellular applications in imaging and biosensing, but their functions as precise regulators in living systems are still limited. Inspired by protein photosensitizers, we propose here a genetically encoded RNA aptamer based photosensitizer (GRAP). Upon illumination, the RNA photosensitizer can controllably generate reactive oxygen species for targeted cell regulation. The GRAP system can be selectively activated by endogenous stimuli and light of different wavelengths. Compared with their protein analogues, GRAP is highly programmable and exhibits reduced off-target effects. These results indicate that GRAP enables efficient noninvasive target cell ablation with high temporal and spatial precision. This new RNA regulator system will be widely used for optogenetics, targeted cell ablation, subcellular manipulation, and imaging.


Assuntos
Aptâmeros de Nucleotídeos/metabolismo , Escherichia coli/metabolismo , Fármacos Fotossensibilizantes/metabolismo , Aptâmeros de Nucleotídeos/genética , Escherichia coli/citologia , Células HeLa , Humanos , Imagem Óptica , Fármacos Fotossensibilizantes/química , Espécies Reativas de Oxigênio/metabolismo
11.
J Am Chem Soc ; 142(6): 2968-2974, 2020 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-31968164

RESUMO

In situ amplification methods, such as hybridization chain reaction, are valuable tools for mapping the spatial distribution and subcellular location of target analytes. However, the live-cell applications of these methods are still limited due to challenges in the probe delivery, degradation, and cytotoxicity. Herein, we report a novel genetically encoded in situ amplification method to noninvasively image the subcellular location of RNA targets in living cells. In our system, a fluorogenic RNA reporter, Broccoli, was split into two nonfluorescent fragments and conjugated to the end of two RNA hairpin strands. The binding of one target RNA can then trigger a cascaded hybridization between these hairpin pairs and thus activate multiple Broccoli fluorescence signals. We have shown that such an in situ amplified strategy can be used for the sensitive detection and location imaging of various RNA targets in living bacterial and mammalian cells. This new design principle provides an effective and versatile platform for tracking various intracellular analytes.


Assuntos
Hibridização de Ácido Nucleico/métodos , RNA/metabolismo , Frações Subcelulares/metabolismo , Corantes Fluorescentes/química , Limite de Detecção
12.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 49(3): 291-296, 2020 05 25.
Artigo em Chinês | MEDLINE | ID: mdl-32762164

RESUMO

OBJECTIVE: To evaluate the efficacy and safety of the third-generation aromatase inhibitor letrozole in the treatment of McCune-Albright syndrome (MAS) girls with peripheral precocious puberty. METHODS: Twenty-one MAS girls with peripheral precocious puberty treated in Pediatrics Department of Ruijin Hospital, Shanghai Jiao Tong University School of Medicine from March 2012 to June 2017 were enrolled in the study. Patients presented with repeated vaginal bleeding, premature breast enlargement, café-au-lait spots or dysplasia of bone fibers, and low levels of luteinizing hormone (LH) and follicle-stimulating hormone (FSH); and the congenital adrenal hyperplasia, estrogen-producing tumors, and exogenous estrogen intake were excluded. Letrozole were administrated at a dose of 0.5-2 mg·m -2·d -1 for 6 to 12 months. The patients were observed for changes in breast staging, vaginal bleeding, sex hormone levels, liver function and bone age changes, and changes in uterine and ovarian volume. RESULTS: After treatment, bone age/chronological age (BA/CA)was decreased from 1.23±0.30 to 1.11±0.18 ( P < 0.01); the predicted adult height (PAH) increased from (156.2±5.9)cm to (158.4±2.1)cm after treatment ( P < 0.05); the vaginal bleeding was reduced and the estradiol level decreased, while the teststosterone level and the uterus showed no significant increase, and no adverse reactions such as ovarian torsion and abnormal liver function were observed. CONCLUSIONS: Precocious puberty is one of the most common endocrine manifestations in MAS. Our findings suggest that letrozole may be an effective and safe therapy to precocious puberty in girls with McCune-Albright Syndrome.


Assuntos
Displasia Fibrosa Poliostótica , Puberdade Precoce , Inibidores da Aromatase , Criança , China , Feminino , Humanos , Letrozol
13.
Proc Natl Acad Sci U S A ; 116(43): 21427-21437, 2019 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-31601737

RESUMO

Pharmacology and optogenetics are widely used in neuroscience research to study the central and peripheral nervous systems. While both approaches allow for sophisticated studies of neural circuitry, continued advances are, in part, hampered by technology limitations associated with requirements for physical tethers that connect external equipment to rigid probes inserted into delicate regions of the brain. The results can lead to tissue damage and alterations in behavioral tasks and natural movements, with additional difficulties in use for studies that involve social interactions and/or motions in complex 3-dimensional environments. These disadvantages are particularly pronounced in research that demands combined optogenetic and pharmacological functions in a single experiment. Here, we present a lightweight, wireless, battery-free injectable microsystem that combines soft microfluidic and microscale inorganic light-emitting diode probes for programmable pharmacology and optogenetics, designed to offer the features of drug refillability and adjustable flow rates, together with programmable control over the temporal profiles. The technology has potential for large-scale manufacturing and broad distribution to the neuroscience community, with capabilities in targeting specific neuronal populations in freely moving animals. In addition, the same platform can easily be adapted for a wide range of other types of passive or active electronic functions, including electrical stimulation.


Assuntos
Optogenética/métodos , Farmacologia/métodos , Animais , Encéfalo/metabolismo , Química Encefálica , Channelrhodopsins/metabolismo , Estimulação Elétrica , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Optogenética/instrumentação , Farmacologia/instrumentação , Próteses e Implantes , Tecnologia sem Fio/instrumentação
14.
Sci Adv ; 5(7): eaaw5296, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31281895

RESUMO

Studies of the peripheral nervous system rely on controlled manipulation of neuronal function with pharmacologic and/or optogenetic techniques. Traditional hardware for these purposes can cause notable damage to fragile nerve tissues, create irritation at the biotic/abiotic interface, and alter the natural behaviors of animals. Here, we present a wireless, battery-free device that integrates a microscale inorganic light-emitting diode and an ultralow-power microfluidic system with an electrochemical pumping mechanism in a soft platform that can be mounted onto target peripheral nerves for programmed delivery of light and/or pharmacological agents in freely moving animals. Biocompliant designs lead to minimal effects on overall nerve health and function, even with chronic use in vivo. The small size and light weight construction allow for deployment as fully implantable devices in mice. These features create opportunities for studies of the peripheral nervous system outside of the scope of those possible with existing technologies.


Assuntos
Encéfalo/fisiopatologia , Optogenética/métodos , Nervos Periféricos , Tecnologia sem Fio , Animais , Humanos , Camundongos , Neurotransmissores/farmacologia , Próteses e Implantes
15.
Sci Total Environ ; 551-552: 143-54, 2016 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-26878632

RESUMO

This paper presents a system for determining the evaluation and gradation indices of groundwater pollution intensity (GPI). Considering the characteristics of the vadose zone and pollution sources, the system decides which anti-seepage measures should be implemented at the contaminated site. The pollution sources hazards (PSH) and groundwater intrinsic vulnerability (GIV) are graded by the revised Nemerow Pollution Index and an improved DRTAS model, respectively. GPI is evaluated and graded by a double-sided multi-factor coupling model, which is constructed by the matrix method. The contaminated sites are categorized as prior, ordinary, or common sites. From the GPI results, we develop guiding principles for preventing and removing pollution sources, procedural interruption and remediation, and end treatment and monitoring. Thus, we can select appropriate prevention and control technologies (PCT). To screen the technological schemes and optimize the traditional analytical hierarchy process (AHP), we adopt the technique for order preference by the similarity to ideal solution (TOPSIS) method. Our GPI approach and PCT screening are applied to three types of pollution sites: the refuse dump of a rare earth mine development project (a potential pollution source), a chromium slag dump, and a landfill (existing pollution sources). These three sites are identified as ordinary, prior, and ordinary sites, respectively. The anti-seepage materials at the refuse dump should perform as effectively as a 1.5-m-thick clay bed. The chromium slag dump should be preferentially treated by soil flushing and in situ chemical remediation. The landfill should be treated by natural attenuation technology. The proposed PCT screening approach was compared with conventional screening methods results at the three sites and proved feasible and effective. The proposed method can provide technical support for the monitoring and management of groundwater pollution in China.


Assuntos
Monitoramento Ambiental , Água Subterrânea/química , Poluentes Químicos da Água/análise , China , Poluição Química da Água/estatística & dados numéricos
16.
Acta Crystallogr E Crystallogr Commun ; 71(Pt 4): 414-7, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-26029403

RESUMO

The crystal structures are reported of the isomeric compounds 2-(4-nitro-phen-yl)-3-phenyl-2,3-di-hydro-4H-1,3-benzo-thia-zin-4-one, (I), and 2-(2-nitro-phen-yl)-3-phenyl-2,3-di-hydro-4H-1,3-benzo-thia-zin-4-one, (II), both C20H14N2O3S, being the para-nitro and ortho-nitro forms, respectively, the meta-form of which is known [Yennawar et al. (2013). Acta Cryst. E69, o1679]. The six-membered thia-zone ring fused with a benzene ring displays a screw-boat conformation with a total puckering amplitude of 0.627 (1) Šin (I), and a near screw-boat conformation with a total puckering amplitude of 0.600 (1) Šin (II). The dihedral angles between the planes of the substituent nitrophenyl and phenyl and rings with the benzene ring of the parent benzo-thia-zone moiety are 75.93 (5) and 82.61 (5)° [in (I)], and 76.79 (6) and 71.66 (6)° [in (II)]. Weak inter-molecular C-H⋯O hydrogen-bonding inter-actions between aromatic H-atom donors and both a nitro-O atom and a thia-zone O-atom acceptor in (I) and a thia-zone O atom in (II) are present, forming in (I) a centrosymmetric 22-membered cyclic dimer which is extended through a similar inversion-related 14-membered cyclic hydrogen-bonding association into a zigzag chain structure extending along c. In (II), a single inter-molecular C-H⋯O hydrogen bond gives a chain structure extending along b. In addition, weak C-H⋯π inter-actions are present in both structures [minimum C⋯ring-centroid separations = 3.630 (2) and 3.581 (2) Å, respectively].

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