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1.
Biomater Sci ; 2021 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-33616151

RESUMO

Carbon monoxide (CO) based gas therapy has been an emerging strategy for cancer treatment. However, the uncontrolled release of CO and limited therapeutic efficacy of monotherapy are two major obstacles for clinical application. To overcome these issues, human serum albumin (HSA) nanoparticles combined with manganese dioxide (MnO2) were developed to deliver a photosensitizer (IR780) and CO donor (MnCO) for a synergistic therapy combining CO gas therapy and phototherapy. The nanoparticles (HIM-MnO2) formed catalyze hydrogen peroxide to produce oxygen for hypoxia relief. With laser irradiation, it can increase the generation of reactive oxygen species for the enhancement of photodynamic therapy (PDT). Furthermore, the generated heat of photothermal therapy (PTT) induced by nanoparticles could trigger the release of CO to achieve a therapeutic window for enhanced gas therapy. Due to the co-localization of IR780 in mitochondria, HIM-MnO2 could accumulate in mitochondria for the synergistic therapy combining CO gas therapy and phototherapy, and could oxidize the mitochondrial membrane and induce more apoptosis. After intravenous injection into tumor bearing mice, HIM-MnO2 could accumulate at tumor sites and with laser irradiation, tumor growth was significantly inhibited due to the enhanced PDT, PTT, and CO gas therapy. This study provides a strategy with oxygen generating and thermal-responsive CO release to combine phototherapy and CO gas therapy for cancer treatment.

2.
Int J Med Sci ; 18(6): 1484-1491, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33628106

RESUMO

Background: Cathepsin B (CTSB) was well documented in solid tumors, up-regulated of CTSB expression is linked with progression of tumors. However, the study of CTSB in adult leukemia has not been reported. Methods: Total RNA was isolated from PBMC (peripheral blood mononuclear cell) of AML patients and healthy donors. qRT-PCR was performed to detect the expression of CTSB. The association of CTSB expression with the patients' overall survival (OS) and disease-free survival (DFS) were analyzed. Stable HL-60 CTSB-shRNA cell lines were established by retrovirus infection and puromycin selection. Cell proliferation was detected by CCK-8 analysis. Tumorigenesis ability was analyzed by soft agar and xenograft nude mice model. Western blot was performed to detect the expression of CTSB and the proteins of cell signaling pathway. Results: The mRNA expression level of CTSB was up-regulated in AML patients compared to healthy control (p<0.001), and CTSB expression was significantly higher in M1, M2, M4 and M5 AML samples than healthy control. The CTSB expression in AML was associated with WBC count (p=0.037). Patients with high CTSB expression had a relatively poor OS (p=0.007) and a shorter DFS (p=0.018). Moreover, the expression level of CTSB may act as an independent prognostic factor for both OS (p=0.011) and DFS (p=0.004). Knockdown CTSB expression in HL-60 cells could inhibit the cells' proliferation and tumorigeneses in vitro and in vivo. Further study showed knockdown CTSB expression in HL-60 cells could inactive the AKT signaling pathway. Conclusions: CTSB mRNA was upregulated in AML patients. CTSB overexpression was correlated with poor prognosis and may serve as an independent prognostic factor for both OS and DFS in AML patients. Knockdown CTSB expression in HL-60 cells could inhibit the cells' proliferation and tumorigenesis. The underlying mechanism may be the inhibition of the AKT signaling pathway.

3.
Hum Brain Mapp ; 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33624333

RESUMO

Canonical correlation analysis (CCA), a multivariate approach to identifying correlations between two sets of variables, is becoming increasingly popular in neuroimaging studies on brain-behavior relationships. However, the CCA stability in neuroimaging applications has not been systematically investigated. Although it is known that the number of subjects should be greater than the number of variables due to the curse of dimensionality, it is unclear at what subject-to-variable ratios (SVR) and at what correlation strengths the CCA stability can be maintained. Here, we systematically assessed the CCA stability, in the context of investigating the relationship between the brain structural/functional imaging measures and the behavioral measures, by measuring the similarity of the first-mode canonical variables across randomly sampled subgroups of subjects from a large set of 936 healthy subjects. Specifically, we tested how the CCA stability changes with SVR under two different brain-behavior correlation strengths. The same tests were repeated using an independent data set (n = 700) for validation. The results confirmed that both SVR and correlation strength affect greatly the CCA stability-the CCA stability cannot be guaranteed if the SVR is not sufficiently high or the brain-behavior relationship is not sufficiently strong. Based on our quantitative characterization of CCA stability, we provided a practical guideline to help correct interpretation of CCA results and proper applications of CCA in neuroimaging studies on brain-behavior relationships.

4.
Artigo em Inglês | MEDLINE | ID: mdl-33605134

RESUMO

Benefitting from narrow band gap nonfullerene acceptors, continually increasing power conversion efficiency (PCE) endows organic solar cells (OSCs) with great potential for commercial application. Fabricating high-performance OSCs with potential for large-scale coating and nonhalogenated solvent processing is a necessity. Herein, we have proposed the use of nonhalogenated solvents combined with high-temperature blade coating to prepare a PM6 (poly[(2,6-(4,8-bis(5-(2-ethylhexyl-3-fluoro)thiophen-2-yl)benzo[1,2-b:4,5-b']dithiophene))-alt-(5,5-(1',3'-di-2-thienyl-5',7'-bis(2-ethylhexyl)benzo[1',2'-c:4',5'-c']dithiophene-4,8-dione)]):Y6 (2,2'-((2Z,2'Z)-((12,13-bis(2-ethylhexyl)-3,9-diundecyl-12,13-dihydro-[1,2,5]thiadiazolo[3,4-e]thieno[2″,3'':4',5']thieno[2',3':4,5]pyrrolo[3,2-g]thieno[2',3':4,5]thieno[3,2-b]indole-2,10-diyl)bis(methanylylidene))bis(5,6-difluoro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene)))blend active layer. The resultant OSCs deliver a PCE of 15.51% when the PM6:Y6 active layer is blade-coated at 90 °C in nonhalogenated o-xylene (o-XY) host solvent containing 1,2-dimethylnaphthalene (DMN) additive. It is found that high-temperature blade coating and nonhalogenated solvent additive DMN can suppress excessive aggregation of Y6 and enhance the crystallinity of PM6 and Y6 by regulating the dynamic process of active layer formation. Finally, an optimized blend morphology with nanofibrous phase separation and enhanced crystallinity are achieved for the PM6:Y6 active layer prepared with high-temperature blade coating and nonhalogenated o-XY:DMN solvents, which not only shortens the film-drying time but also leads to increased charge generation, transport, and collection efficiency. The 1.00 cm2 OSCs prepared with high-temperature blade coating and nonhalogenated solvents exhibit a high PCE of 13.87%. This approach shows great potential for large-area fabrication of OSCs.

5.
Sci Rep ; 11(1): 2078, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33483530

RESUMO

An efficient [4 + 1] annulation between α-bromooximes and sulfur ylides via in situ generation of nitrosoalkenes under mild basic reaction conditions has been developed, providing an expeditious and scalable approach to synthesize biologically interesting isoxazoline derivatives with good to excellent yields.

6.
Nat Commun ; 12(1): 20, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33397932

RESUMO

Drug resistance and tumor recurrence are major challenges in cancer treatment. Cancer cells often display centrosome amplification. To maintain survival, cancer cells achieve bipolar division by clustering supernumerary centrosomes. Targeting centrosome clustering is therefore considered a promising therapeutic strategy. However, the regulatory mechanisms of centrosome clustering remain unclear. Here we report that KIFC1, a centrosome clustering regulator, is positively associated with tumor recurrence. Under DNA damaging treatments, the ATM and ATR kinases phosphorylate KIFC1 at Ser26 to selectively maintain the survival of cancer cells with amplified centrosomes via centrosome clustering, leading to drug resistance and tumor recurrence. Inhibition of KIFC1 phosphorylation represses centrosome clustering and tumor recurrence. This study identified KIFC1 as a prognostic tumor recurrence marker, and revealed that tumors can acquire therapeutic resistance and recurrence via triggering centrosome clustering under DNA damage stresses, suggesting that blocking KIFC1 phosphorylation may open a new vista for cancer therapy.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Centrossomo/metabolismo , Cinesina/metabolismo , Recidiva Local de Neoplasia/metabolismo , Sequência de Aminoácidos , Animais , Linhagem Celular Tumoral , Instabilidade Cromossômica , Dano ao DNA , Resistencia a Medicamentos Antineoplásicos , Humanos , Cinesina/química , Camundongos , Recidiva Local de Neoplasia/patologia , Fosforilação , Fosfosserina/metabolismo
7.
Food Chem ; 347: 129085, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33493837

RESUMO

Zanthoxylum Bungeanum Maxim. is an important seasoning in Chinese cooking, but its bitter taste limits its use by some consumers. In this study, metabolomic analysis based on ultra-high-performance liquid chromatograph-tandem mass spectrometry (UPLC-MS) was used to screen out a vast number of potential non-volatile bitter compounds in Z. bungeanum. Results showed that there were 37 potential bitter compounds in Z. bungeanum, and possible mechanisms underlying its bitter taste were provided. Further, instrumental analyses combined with sensory evaluation were used to identify the key bitter compounds in Gou jiao, a wild variant of Z. Bungeanum with a strong bitter taste. Totally 15 key bitter compounds were identified, most of which have a low bitterness recognition threshold. This study is the first comprehensive identification of non-volatile bitter compounds in Z. bungeanum and provides a basis for future investigations into mitigating bitterness and uncovering how the interaction between different bitter compounds affects taste.

8.
J Hazard Mater ; 403: 123975, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33265016

RESUMO

The newly introduced Cd (CdN) has different environmental fates than legacy Cd (CdL) and how to distinguish them in soil under different amendments is crucial for understanding natural aging and engineered remediation of Cd pollution in soil. In this study, enriched stable isotope tracer (112Cd) was introduced to distinguish the fate of CdN and CdL in paddy soil under pH adjustment and quicklime, slaked lime, and biochar amendments. The behaviors of CdN and CdL were studied during 56 days of flooding incubation through overlying water analysis, sequential extraction fractionation and lability (exchangeable pool probed by 110Cd isotopic spike) assessment. The results showed that soil pH is the main driving factor controlling the partition of both CdN and CdL in overlying water. During the incubation, CdN transformed quickly from soluble fraction to residual fraction under all treatments. In addition, at the end of the incubation, CdN concentrations in residual fraction were much higher than that of CdL, suggesting a more thorough aging of CdN than CdL. The labile CdN (ECdN) under pH adjustment and biochar amendment decreased during incubation and ECdN% was essentially the same with that of ECdL% after 28 days, indicating the aging equilibrium of exchangeable pool of CdN.

9.
Physiol Mol Biol Plants ; 26(11): 2189-2197, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33268922

RESUMO

The clade A members of serine/threonine protein phosphatase 2Cs (PP2Cs) play crucial roles in plant growth, development, and stress response via the ABA signaling pathway. But little is known about other PP2C clades in plants. Our previous study showed that maize the ZmPP2C26, a clade B member of ZmPP2Cs, negatively regulated drought tolerance in transgenic Arabidopsis. However, the upstream regulatory mechanism of ZmPP2C26 remains unclear. In the present study, the expression of ZmPP2C26 gene in maize was analyzed by quantitative real time PCR (qRT-PCR). The results showed that the expression of ZmPP2C26 in shoot and root was both significantly inhibited by drought stress. Subsequently, a 2175 bp promoter of ZmPP2C26 was isolated from maize genome (P 2175). To validate whether the promoter possess some key cis-element and negatively drive ZmPP2C26 expression in drought stress, three 5´-deletion fragments of 1505, 1084 and 215 bp was amplified from P 2175 and were fused to ß-glucuronidase (GUS) and luciferase gene (LUC) to produce promoter::GUS and promoter::LUC constructs, and transformed into tobacco, respectively. Transient expression assays indicated that all promoters could drive GUS and LUC expression. The GUS and LUC activity were both significantly inhibited by PEG-6000 treatment. Notably, the - 1084 to - 215 bp promoter possess one MBS element and inhibits the expression of GUS and LUC under drought stress. Meanwhile, we found that the 215 bp length is enough to drive ZmPP2C26 expression. These findings will provide insights into understanding the transcription-regulatory mechanism of ZmPP2C26 negatively regulating drought tolerance.

10.
Chemphyschem ; 2020 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-33319485

RESUMO

The replacement of a CH group of benzene by a triel (Tr) atom places a positive region of electrostatic potential near the Tr atom in the plane of the aromatic ring. This σ-hole can interact with an X lone pair of XCCH (X=F, Cl, Br, and I) to form a triel bond (TrB). The interaction energy between C5 H5 Tr and FCCH lies in the range between 2.2 and 4.4 kcal/mol, in the order Tr=B

11.
Gastroenterol. hepatol. (Ed. impr.) ; 43(10): 640-648, dic. 2020. tab, graf
Artigo em Inglês | IBECS | ID: ibc-ET2-7619

RESUMO

BACKGROUND: Tenofovir disoproxil fumarate (TDF) is recommended for the prevention of perinatal transmission of the hepatitis B virus (HBV). This study aimed to systematically assess the efficacy and safety of TDF in pregnant women with chronic HBV and their infants. MATERIAL AND METHODS: Database searches were performed to identify studies blocking the mother-to-child transmission of the hepatitis B virus with tenofovir. The search included pregnant women with chronic HBV infection administered with TDF compared to the no treatment controls, and data from individual studies were pooled using RevMan v5.3 for meta-analysis. RESULTS: Seven studies with a total of 911 patients met the inclusion criteria: 433 patients in the TDF group and 478 patients in the non-TDF group. The HBV mother-to-child transmission rate in the tenofovir group was effectively reduced compared to the control group (RR: 0.18, 95% CI: 0.08-0.40). HBV-DNA positivity was also significantly low in infants from TDF group (RR: 0.17, 95% CI: 0.10-0.30) and the TDF treatment resulted in significantly higher anti-HBs production (RR: 1.11, 95% CI: 1.04-1.18). Similarly, maternal HBV-DNA was suppression was significantly high in the TDF group (RR: 34.16, 95% CI: 16.40-71.13). Women treated with TDF and their infants did not result in serious adverse events that are statistically different as compared to the women who did not receive any treatment. CONCLUSION: Treatment of HBV infected pregnant women with TDF can effectively and safely prevent the perinatal transmission of chronic hepatitis B


ANTECEDENTES: El fumarato de disoproxilo de tenofovir (FDT) se recomienda para la prevención de la transmisión perinatal del virus de la hepatitis B (VHB). El objetivo de este estudio fue evaluar de manera sistemática la eficacia y la seguridad del FDT en las mujeres embarazadas con VHB crónico y en sus hijos lactantes. MATERIAL Y MÉTODOS: Se realizaron búsquedas en las bases de datos para identificar los estudios sobre el bloqueo de la transmisión del virus de la hepatitis B de madre a hijo con el tenofovir. La búsqueda incluyó a mujeres embarazadas con infección crónica por el VHB que recibieron FDT en comparación con controles sin tratamiento, y los datos de los estudios individuales se agruparon mediante el uso de RevMan v5.3 para el metaanálisis. RESULTADOS: Los criterios de inclusión se cumplieron en siete estudios con un total de 911 pacientes: 433 pacientes en el grupo de FDT y 478 pacientes en el grupo sin FDT. La tasa de transmisión de madre a hijo del VHB en el grupo de tenofovir se redujo efectivamente en comparación con el grupo de control (RR: 0,18, IC del 95 %: 0,08-0,40). Los resultados positivos del ADN del VHB también fueron significativamente bajos en los infantes del grupo de FDT (RR: 0,17, IC del 95 %: 0,10-0,30) y el tratamiento con FDT dio como resultado una producción significativamente mayor de anti-HB (RR: 1,11, IC del 95 %: 1,04-1,18). Del mismo modo, la supresión del ADN del VHB materno fue significativamente alta en el grupo del FDT (RR: 34,16, IC del 95 %: 16,40-71,13). El tratamiento de las mujeres con FDT y sus hijos lactantes no provocó acontecimientos adversos graves en ellas ni en sus hijos que fueran estadísticamente diferentes de los de las mujeres que no recibieron ningún tratamiento. CONCLUSIÓN: El tratamiento con FDT de las mujeres embarazadas infectadas por el VHB puede prevenir de manera eficaz y segura la transmisión perinatal de la hepatitis B crónica


Assuntos
Humanos , Feminino , Gravidez , Lactente , Adulto , Hepatite B/tratamento farmacológico , Hepatite B/prevenção & controle , Resultado do Tratamento , Segurança do Paciente , Tenofovir/uso terapêutico , Hepatite B/transmissão , Transmissão Vertical de Doença Infecciosa/prevenção & controle , Transmissão Vertical de Doença Infecciosa/estatística & dados numéricos
12.
Artigo em Inglês | MEDLINE | ID: mdl-33161490

RESUMO

Broad-spectrum antibodies can effectively recognize substances with similar structures and have broad application prospects in field rapid detection. In this study, broad-spectrum antibodies (Abs) against organophosphorus pesticides (OPs) were used as sensitive recognition elements, which could effectively recognize most OPs. Gold nanoparticles (AuNPs) have good biocompatibility. It combined with Abs to form a gold-labeled probe (AuNPs-Abs), which enhances the effective binding of antibodies to nanomaterials. Prussian blue (PB) was added to electrodeposition solution to enhance the conductivity, resulting in superior electrochemical performance. The AuNP-Abs-PB composite film was prepared by electrodeposition on the electrode surface to improve the anti-interference ability and stability of the immunosensor. Under the optimal experimental conditions, the immunosensor had a wide detection range (IC20-IC80: 1.82 × 10-3-3.29 × 104 ng/mL) and high sensitivity. Most importantly, it was simple to be prepared and could be used to detect multiple OPs.

13.
Sensors (Basel) ; 20(22)2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33217912

RESUMO

Immunoassay has the advantages of high sensitivity, high specificity, and simple operation, and has been widely used in the detection of mycotoxins. For several years, time-resolved fluorescence immunochromatography (TRFIA) paper-based sensors have attracted much attention as a simple and low-cost field detection technology. However, a traditional TRFIA paper-based sensor is based on antibody labeling, which cannot easily meet the current detection requirements. A second antibody labeling method was used to amplify the fluorescence signal and improve the detection sensitivity. Polystyrene fluorescent microspheres were combined with sheep anti-mouse IgG to prepare fluorescent probes (Eu-IgGs). After the probe fully reacted with the antibody (Eu-IgGs-Abs) in the sample cell, it was deployed on the paper-based sensor using chromatography. Eu-IgGs-Abs that were not bound to the target were captured on the T-line, while those that were bound were captured on the C-line. The paper-based sensor reflected the corresponding fluorescence intensity change. Because a single molecule of the deoxynivalenol antibody could bind to multiple Eu-IgGs, this method could amplify the fluorescence signal intensity on the unit antibody and improve the detection sensitivity. The working standard curve of the sensor was established under the optimum working conditions. It showed the lower limit of detection and higher recovery rate when it was applied to actual samples and compared with other methods. This sensor has the advantages of high sensitivity, good accuracy, and good specificity, saving the amount of antibody consumed and being suitable for rapid field detection of deoxynivalenol.

14.
J Exp Bot ; 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33206180

RESUMO

The BES1/BZR1 transcription factors regulate the expression of brassinosteroid responsive genes and play pivotal roles in plant development. However, the function of BES1/BZR1 regulating kernel development remains unclear. In this study, maize ZmBES1/BZR1-5 is found to positively regulate kernel size. Candidate-gene association analysis showed that four and three SNPs related to ZmBES1/BZR1-5 were significantly associated with kernel width and 100-kernel weight in 513 diverse maize inbred lines, respectively. Overexpression of ZmBES1/BZR1-5 gene in Arabidopsis and rice both significantly increased seed size and weight, as well as smaller kernel produced in maize Mu transposon insertion and EMS mutants. The ZmBES1/BZR1-5 protein contains bHLH and BAM domains, shows no transcriptional activity as monomer but forms homodimer through BAM domain, and locates in nucleus. Chromatin immunoprecipitation sequencing (ChIP-seq), yeast one-hybrid (Y1H) and dual-luciferase assay demonstrate that ZmBES1/BZR1-5 protein binds to the promoter of AP2/EREBP genes (Zm00001d010676 and Zm00001d032077) and inhibits their transcription. cDNA library screening shows that ZmBES1/BZR1-5 interacts with casein kinase II subunit ß4 (ZmCKIIß4) and ferredoxin 2 (ZmFdx2) in vitro and vivo, respectively. Taken together, the study suggests that ZmBES1/BZR1-5 positively regulates kernel size and provides new insights into understanding the mechanism of kernel development in maize.

15.
Appl Environ Microbiol ; 86(24)2020 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-33036989

RESUMO

Pseudomonas fluorescens 2P24 is a rhizosphere bacterium that protects many crop plants against soilborne diseases caused by phytopathogens. The PcoI/PcoR quorum-sensing (QS) system and polyketide antibiotic 2,4-diacetylphloroglucinol (2,4-DAPG) are particularly relevant to the strain's biocontrol potential. In this study, we investigated the effects of c-di-GMP on the biocontrol activity of strain 2P24. The expression of the Escherichia coli diguanylate cyclase (YedQ) and phosphodiesterase (YhjH) in P. fluorescens 2P24 significantly increased and decreased the cellular concentration of c-di-GMP, respectively. The production of the QS signals N-acyl homoserine lactones (AHLs) and 2,4-DAPG was negatively regulated by c-di-GMP in 2P24. The regulatory proteins RsmA and RsmE were positively regulated by c-di-GMP. Genomic analysis revealed that 2P24 has 23 predicted proteins that contain c-di-GMP-synthesizing or -degrading domains. Among these proteins, C0J56_12915, C0J56_13325, and C0J56_27925 contributed to the production of c-di-GMP and were also involved in the regulation of the QS signal and antibiotic 2,4-DAPG production in P. fluorescens Overexpression of C0J56_12915, C0J56_13325, and C0J56_27925 in 2P24 impaired its root colonization and biocontrol activities. Taken together, these results demonstrated that c-di-GMP played an important role in fine-tuning the biocontrol traits of P. fluorescens IMPORTANCE In various bacteria, the bacterial second messenger c-di-GMP influences a wide range of cellular processes. However, the function of c-di-GMP on biocontrol traits in the plant-beneficial rhizobacteria remains largely unclear. The present work shows that the QS system and polyketide antibiotic 2,4-DAPG production are regulated by c-di-GMP through RsmA and RsmE proteins in P. fluorescens 2P24. The diguanylate cyclases (DGCs) C0J56_12915, C0J56_13325, and C0J56_27925 are especially involved in regulating the biocontrol traits of 2P24. Our work also demonstrated a connection between the Gac/Rsm cascade and the c-di-GMP signaling pathway in P. fluorescens.

16.
Chem Commun (Camb) ; 56(88): 13559-13562, 2020 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-33048088

RESUMO

We present X-ray-excitable organic ultralong room temperature phosphorescence (X-OURTP) for afterglow scintillators through implanting lone-pair electron involved n-π* transitions and efficient charge transfer characters into H-aggregations of organic crystals. The thus designed X-OURTP molecule exhibits ultralong lifetimes up to 790 ms, high phosphorescence quantum yields of ∼8%, and excellent scintillation stability. These findings will pave the way to the design of organic afterglow scintillators, simulating extensive investigations on the extraordinary X-OURTP.

17.
ACS Omega ; 5(33): 21300-21308, 2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-32875266

RESUMO

The complexes of TrR3 (Tr = B and Al; R = H, F, Cl, and Br) with three N-bases (NH3, CH2NH, and HCN) and three O-bases (CH3OH, H2CO, and CO) are utilized to explore the hybridization effect of N and O atoms on the strength, properties, and nature of the triel bond. The sp-hybridized O and N atoms form the weakest triel bond, followed by the sp2-hybridized O atom or the sp3-hybridized N atom, and the sp3-hybridized O atom or the sp2-hybridized N atom engages in the strongest triel bond. The hybridization effect is also related to the substituent of TrR3. Most complexes are dominated by electrostatic, with increasing polarization contribution from sp to sp2 to sp3. Although the CO oxygen engages in a weaker triel bond, its carbon atom is a better electron donor and the interaction energy even amounts to -37 kcal/mol in the BH3 complex.

18.
Plant Biotechnol J ; 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-32945115

RESUMO

Lysine is the main limiting essential amino acid (EAA) in the rice seeds, which is a major energy and nutrition source for humans and livestock. In higher plants, the rate-limiting steps in lysine biosynthesis pathway are catalysed by two key enzymes, aspartate kinase (AK) and dihydrodipicolinate synthase (DHDPS), and both are extremely sensitive to feedback inhibition by lysine. In this study, two rice AK mutants (AK1 and AK2) and five DHDPS mutants (DHDPS1-DHDPS5), all single amino acid substitution, were constructed. Their protein sequences passed an allergic sequence-based homology alignment. Mutant proteins were recombinantly expressed in Escherichia coli, and all were insensitive to the lysine analog S-(2-aminoethyl)-l-cysteine (AEC) at concentrations up to 12 mm. The AK and DHDPS mutants were transformed into rice, and free lysine was elevated in mature seeds of transgenic plants, especially those expressing AK2 or DHDPS1, 6.6-fold and 21.7-fold higher than the wild-type (WT) rice, respectively. We then engineered 35A2D1L plants by simultaneously expressing modified AK2 and DHDPS1, and inhibiting rice LKR/SDH (lysine ketoglutaric acid reductase/saccharopine dehydropine dehydrogenase). Free lysine levels in two 35A2D1L transgenic lines were 58.5-fold and 39.2-fold higher than in WT and transgenic rice containing native AK and DHDPS, respectively. Total free amino acid and total protein content were also elevated in 35A2D1L transgenic rice. Additionally, agronomic performance analysis indicated that transgenic lines exhibited normal plant growth, development and seed appearance comparable to WT plants. Thus, AK and DHDPS mutants may be used to improve the nutritional quality of rice and other cereal grains.

19.
Nutrition ; 79-80: 110974, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32947129

RESUMO

Intermittent fasting (IF) and energy-restricted diets (ERDs) have emerged as dietary approaches to decrease inflammatory status; however, there are no consistent results regarding humans. To achieve a comprehensive conclusion, we aimed to conduct a meta-analysis of randomized control trials (RCTs) to evaluate the effects of IF or ERDs on plasma concentrations of inflammatory biomarkers. We systematically searched online medical databases including Web of Sciences, PubMed, SCOPUS, and Google Scholar up to June 2019. Evaluations of effect sizes were described employing in weighted mean difference and 95% confidence intervals from the random-effects model. Eighteen eligible RCTs were included in this meta-analysis. The pooled estimation from the random-effect model showed that IF regimens and ERDs significantly reduced C-reactive protein (CRP) concentrations (WMD: -0.024 mg/dL; 95% CI: -0.044 to -0.005, I2 = 7.0%). Additionally, IF regimens (WMD: -0.029; 95% CI: -0.058 to -0.000, I2 = 17.9%) were more effective in reducing CRP levels than ERDs (WMD: -0.001 mg/dL; 95% CI: -0.037 to 0.034, I2 = 0.0%). Moreover, based on the treatment duration and types of the studies' population, a greater reduction was observed in overweight and obese individuals (WMD: -0.03 mg/dL; 95% CI: -0.05 to 0.01, I2 = 42.1%), and in treatment duration ≥8 wk (WMD: -0.03 mg/dL; 95% CI: -0.05 to 0.01, I2 = 0.0%) as well. However, IF and ERDs did not significantly reduced tumor necrosis factor-α (WMD: -0.158 pg/mL; P = 0.549, I2 = 98.3) and interleukin-6 (IL-6) concentrations (WMD: -0.541 pg/mL; P = 0.080, I2 = 94.7%). This meta-analysis demonstrated that IF regimens and ERDs may reduce CRP concentrations, particularly in overweight and obese individuals and through a considerable length of intervention (≥2 mo). However, neither dietary model affected the concentrations of tumor necrosis factor-α or interleukin-6.

20.
Gastroenterol Hepatol ; 43(10): 640-648, 2020 Dec.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32948358

RESUMO

BACKGROUND: Tenofovir disoproxil fumarate (TDF) is recommended for the prevention of perinatal transmission of the hepatitis B virus (HBV). This study aimed to systematically assess the efficacy and safety of TDF in pregnant women with chronic HBV and their infants. MATERIAL AND METHODS: Database searches were performed to identify studies blocking the mother-to-child transmission of the hepatitis B virus with tenofovir. The search included pregnant women with chronic HBV infection administered with TDF compared to the no treatment controls, and data from individual studies were pooled using RevMan v5.3 for meta-analysis. RESULTS: Seven studies with a total of 911 patients met the inclusion criteria: 433 patients in the TDF group and 478 patients in the non-TDF group. The HBV mother-to-child transmission rate in the tenofovir group was effectively reduced compared to the control group (RR: 0.18, 95% CI: 0.08-0.40). HBV-DNA positivity was also significantly low in infants from TDF group (RR: 0.17, 95% CI: 0.10-0.30) and the TDF treatment resulted in significantly higher anti-HBs production (RR: 1.11, 95% CI: 1.04-1.18). Similarly, maternal HBV-DNA was suppression was significantly high in the TDF group (RR: 34.16, 95% CI: 16.40-71.13). Women treated with TDF and their infants did not result in serious adverse events that are statistically different as compared to the women who did not receive any treatment. CONCLUSION: Treatment of HBV infected pregnant women with TDF can effectively and safely prevent the perinatal transmission of chronic hepatitis B.

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