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1.
Plant J ; 118(6): 1907-1921, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38491869

RESUMO

The sex of dioecious plants is mainly determined by genetic factors, but it can also be converted by environmental cues such as exogenous phytohormones. Gibberellic acids (GAs) are well-known inducers of flowering and sexual development, yet the pathway of gibberellin-induced sex conversion in dioecious spinach (Spinacia oleracea L.) remains elusive. Based on sex detection before and after GA3 application using T11A and SSR19 molecular markers, we confirmed and elevated the masculinization effect of GA on a single female plant through exogenous applications of GA3, showing complete conversion and functional stamens. Silencing of GIBBERELLIC ACID INSENSITIVE (SpGAI), a single DELLA family protein that is a central GA signaling repressor, results in similar masculinization. We also show that SpGAI can physically interact with the spinach KNOX transcription factor SHOOT MERISTEMLESS (SpSTM), which is a homolog of the flower meristem identity regulator STM in Arabidopsis. The silencing of SpSTM also masculinized female flowers in spinach. Furthermore, SpSTM could directly bind the intron of SpPI to repress SpPI expression in developing female flowers. Overall, our results suggest that GA induces a female masculinization process through the SpGAI-SpSTM-SpPI regulatory module in spinach. These insights may help to clarify the molecular mechanism underlying the sex conversion system in dioecious plants while also elucidating the physiological basis for the generation of unisexual flowers so as to establish dioecy in plants.


Assuntos
Flores , Regulação da Expressão Gênica de Plantas , Giberelinas , Proteínas de Plantas , Spinacia oleracea , Giberelinas/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Flores/genética , Flores/fisiologia , Spinacia oleracea/genética , Spinacia oleracea/fisiologia , Spinacia oleracea/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética
2.
J Orthop Sci ; 29(2): 681-689, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36775785

RESUMO

BACKGROUND: Cognitive behavioral therapy (CBT) is a structured, short-term psychotherapy approach that may have positive effects in terms of relieving postoperative pain. The main objective of this study was to determine the effect of CBT on pain and joint function in patients after total joint arthroplasty. METHODS: We searched 3 electronic databases including randomized controlled studies (RCTs) using CBT as an intervention. The main results of this study were to determine pain intensity by NRS, VAS, WOMAC pain Scale, PCS, and joint function by HHS, OKS, EQ-5D, ROM. Data extraction and quality assessment of included RCTs were independently performed by the authors and date analysis was performed by RevMan V.5.4. RESULTS: Among the 605 studies, 9 RCTS were included in this systematic review and meta-analysis. The study showed that the difference between CBT and usual care groups in PCS (≤3months), NRS, VAS (≤3months) were statistically significant (P < 0.05); the difference between CBT and usual care groups in PCS (≥12months), WOMAC Pain Scale, and VAS (≥12months) were not statistically significant (P > 0.05), indicating that CBT can improve pain in patients after arthroplasty in the early term. In addition, the difference between CBT and usual care groups in OKS (≤3months), HSS, ROM (≤3months), EQ-5D (≤3months) were not statistically significant (P > 0.05); the difference between CBT and usual care groups in EQ-5D (≥12months) were statistically significant (P < 0.05), indicating that the quality of life in patients after total joint arthroplasty were improved with the extension of follow-up time. CONCLUSIONS: This study shows that CBT can relieve pain in patients with total joint arthroplasty in the early postoperative period and improve quality of life to some extent over time.


Assuntos
Terapia Cognitivo-Comportamental , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Dor Pós-Operatória/terapia , Qualidade de Vida , Artroplastia
3.
Nano Lett ; 23(10): 4390-4398, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37154763

RESUMO

Photocatalysts for seawater splitting are severely restricted because of the presence of multiple types of ions in seawater that cause corrosion and deactivation. As a result, new materials that promote adsorption of H+ and hinder competing adsorption of metal cations should enhance utilization of photogenerated electrons on the catalyst surface for efficient H2 production. One strategy to design advanced photocatalysts involves introduction of hierarchical porous structures that enable fast mass transfer and creation of defect sites that promote selective hydrogen ion adsorption. Herein, we used a facile calcination method to fabricate the macro-mesoporous C3N4 derivative, VN-HCN, that contains multiple nitrogen vacancies. We demonstrated that VN-HCN has enhanced corrosion resistance and elevated photocatalytic H2 production performance in seawater. Experimental results and theoretical calculations reveal that enhanced mass and carrier transfer and selective adsorption of hydrogen ions are key features of VN-HCN that lead to its high seawater splitting activity.

4.
BMC Genomics ; 24(1): 423, 2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37501164

RESUMO

BACKGROUND: Long terminal repeat (LTR)-retrotransposons (LTR-RTs) are ubiquitous and make up the majority of nearly all sequenced plant genomes, whereas their pivotal roles in genome evolution, gene expression regulation as well as their epigenetic regulation are still not well understood, especially in a large number of closely related species. RESULTS: Here, we analyzed the abundance and dynamic evolution of LTR-RTs in 54 species from an economically and agronomically important family, Fabaceae, and also selected two representative species for further analysis in expression of associated genes, transcriptional activity and DNA methylation patterns of LTR-RTs. Annotation results revealed highly varied proportions of LTR-RTs in these genomes (5.1%~68.4%) and their correlation with genome size was highly positive, and they were significantly contributed to the variance in genome size through species-specific unique amplifications. Almost all of the intact LTR-RTs were inserted into the genomes 4 Mya (million years ago), and more than 50% of them were inserted in the last 0.5 million years, suggesting that recent amplifications of LTR-RTs were an important force driving genome evolution. In addition, expression levels of genes with intronic, promoter, and downstream LTR-RT insertions of Glycine max and Vigna radiata, two agronomically important crops in Fabaceae, showed that the LTR-RTs located in promoter or downstream regions suppressed associated gene expression. However, the LTR-RTs within introns promoted gene expression or had no contribution to gene expression. Additionally, shorter and younger LTR-RTs maintained higher mobility and transpositional potential. Compared with the transcriptionally silent LTR-RTs, the active elements showed significantly lower DNA methylation levels in all three contexts. The distributions of transcriptionally active and silent LTR-RT methylation varied across different lineages due to the position of LTR-RTs located or potentially epigenetic regulation. CONCLUSION: Lineage-specific amplification patterns were observed and higher methylation level may repress the activity of LTR-RTs, further influence evolution in Fabaceae species. This study offers valuable clues into the evolution, function, transcriptional activity and epigenetic regulation of LTR-RTs in Fabaceae genomes.


Assuntos
Fabaceae , Retroelementos , Retroelementos/genética , Epigênese Genética , Fabaceae/genética , Evolução Molecular , Genoma de Planta , Sequências Repetidas Terminais/genética , Filogenia
5.
Int J Mol Sci ; 24(6)2023 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-36982920

RESUMO

The aim of this study was to evaluate the radiotherapy (RT)-pharmacokinetics (PK) effect of cabozantinib in concurrent or sequential regimens with external beam radiotherapy (EBRT) or stereotactic body radiation therapy (SBRT). Concurrent and sequential regimens involving RT and cabozantinib were designed. The RT-drug interactions of cabozantinib under RT were confirmed in a free-moving rat model. The drugs were separated on an Agilent ZORBAX SB-phenyl column with a mobile phase consisting of 10 mM potassium dihydrogen phosphate (KH2PO4)-methanol solution (27:73, v/v) for cabozantinib. There were no statistically significant differences in the concentration versus time curve of cabozantinib (AUCcabozantinib) between the control group and the RT2Gy×3 f'x and RT9Gy×3 f'x groups in the concurrent and the sequential regimens. However, compared to those in the control group, the Tmax, T1/2 and MRT decreased by 72.8% (p = 0.04), 49.0% (p = 0.04) and 48.5% (p = 0.04) with RT2Gy×3 f'x in the concurrent regimen, respectively. Additionally, the T1/2 and MRT decreased by 58.8% (p = 0.01) and 57.8% (p = 0.01) in the concurrent RT9Gy×3 f'x group when compared with the control group, respectively. The biodistribution of cabozantinib in the heart increased by 271.4% (p = 0.04) and 120.0% (p = 0.04) with RT2Gy×3 f'x in the concurrent and sequential regimens compared to the concurrent regimen, respectively. Additionally, the biodistribution of cabozantinib in the heart increased by 107.1% (p = 0.01) with the RT9Gy×3 f'x sequential regimen. Compared to the RT9Gy×3 f'x concurrent regimen, the RT9Gy×3 f'x sequential regimen increased the biodistribution of cabozantinib in the heart (81.3%, p = 0.02), liver (110.5%, p = 0.02), lung (125%, p = 0.004) and kidneys (87.5%, p = 0.048). No cabozantinib was detected in the brain in any of the groups. The AUC of cabozantinib is not modulated by irradiation and is not affected by treatment strategies. However, the biodistribution of cabozantinib in the heart is modulated by off-target irradiation and SBRT doses simultaneously. The impact of the biodistribution of cabozantinib with RT9Gy×3 f'x is more significant with the sequential regimen than with the concurrent regimen.


Assuntos
Radiocirurgia , Ratos , Animais , Distribuição Tecidual , Terapia Combinada , Fígado
6.
Int J Mol Sci ; 23(17)2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36077556

RESUMO

Long terminal repeat (LTR)-retrotransposons (LTR-RTs) comprise a major portion of many plant genomes and may exert a profound impact on genome structure, function, and evolution. Although many studies have focused on these elements in an individual species, their dynamics on a family level remains elusive. Here, we investigated the abundance, evolutionary dynamics, and impact on associated genes of LTR-RTs in 16 species in an economically important plant family, Cucurbitaceae. Results showed that full-length LTR-RT numbers and LTR-RT content varied greatly among different species, and they were highly correlated with genome size. Most of the full-length LTR-RTs were amplified after the speciation event, reflecting the ongoing rapid evolution of these genomes. LTR-RTs highly contributed to genome size variation via species-specific distinct proliferations. The Angela and Tekay lineages with a greater evolutionary age were amplified in Trichosanthes anguina, whereas a recent activity burst of Reina and another ancient round of Tekay activity burst were examined in Sechium edule. In addition, Tekay and Retand lineages belonging to the Gypsy superfamily underwent a recent burst in Gynostemma pentaphyllum. Detailed investigation of genes with intronic and promoter LTR-RT insertion showed diverse functions, but the term of metabolism was enriched in most species. Further gene expression analysis in G.pentaphyllum revealed that the LTR-RTs within introns suppress the corresponding gene expression, whereas the LTR-RTs within promoters exert a complex influence on the downstream gene expression, with the main function of promoting gene expression. This study provides novel insights into the organization, evolution, and function of LTR-RTs in Cucurbitaceae genomes.


Assuntos
Evolução Molecular , Retroelementos , Tamanho do Genoma , Genoma de Planta , Filogenia , Retroelementos/genética , Sequências Repetidas Terminais/genética
7.
Zhongguo Zhong Yao Za Zhi ; 47(11): 3038-3048, 2022 Jun.
Artigo em Zh | MEDLINE | ID: mdl-35718528

RESUMO

Based on the brain-gut axis, the present study investigated the effect of Huanglian Houpo Decoction(HLHPD) in the treatment of ulcerative colitis(UC) and explored the mechanism in the regulation of 5-hydroxytryptamine(5-HT), substance P(SP), and vasoactive intestinal peptide(VIP) using modern technologies and molecular docking. Sixty male C57 BL/6 J mice were randomly divided into a blank control group, a model group, a sulfasalazine(SASP) group, and high-(5.00 g·kg~(-1)), medium-(2.50 g·kg~(-1)), and low-dose(1.25 g·kg~(-1)) HLHPD groups. The UC model was induced by oral administration of water containing 3% dextran sulfate sodium salt(DSS) in mice except those in the blank control group. After HLHPD was administered for 10 days, the mice were sacrificed for sample collection. Morphological changes of colon tissues were observed by HE staining. The expression of 5-HT, SP, VIP, tumor necrosis factor α(TNF-α), interleukin-6(IL-6), and interleukin-1ß(IL-1ß) in the hypothalamus, serum, and colon was determined by the enzyme-linked immunosorbent assay(ELISA). The expression of tryptophan hydroxylase 1(TPH1), SP, and VIP in colon tissues was evaluated by immunohistochemistry. The expression of brain-gut peptide receptors, such as 5-HT3 A, neurokinin receptor 1(NK-1 R), and VIP receptor 1(VPAC1) in colon tissues was investigated by Western blot. The binding affinity of the brain-gut peptide receptors to the main components of HLHPD was analyzed by molecular docking. After HLHPD intervention, UC mice showed increased body weight, reduced DAI score and occult blood, prolonged colon, down-regulated levels of TNF-α, IL-1ß, and IL-6 in colon tissues, and relieved pathological damage in the colon. The VIP levels in the colon were significantly up-regulated in the HLHPD groups. The high-and medium-dose HLHPD could significantly down-regulated SP and 5-HT in colon tissues and 5-HT in the serum, and up-regulated the VIP in the serum. The high-dose HLHPD group could down-regulate 5-HT and up-regulate VIP in the hypothalamus. It is suggested that HLHPD can reverse the levels of brain-gut peptides in UC mice to varying degrees. Correlation analysis results suggested that the expression levels of brain-gut peptides in the hypothalamus, serum, and colon tissues were related to inflammatory factors. Molecular docking results showed that berberine, coptisine, and epiberberine were presumedly the material basis for HLHPD in regulating the levels of 5-HT3 A, NK-1 R, and VPAC1. The main components of HLHPD may reduce colonic inflammation and pathological damage of colon tissues by regulating the activity of brain-gut peptides and their receptors, thereby reducing DSS-induced colitis in mice.


Assuntos
Colite Ulcerativa , Animais , Eixo Encéfalo-Intestino , Colite Ulcerativa/tratamento farmacológico , Colo , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas , Interleucina-6/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , Serotonina/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
8.
Chemistry ; 27(57): 14202-14208, 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34379853

RESUMO

Photodriven seawater splitting is considered to be one of the most promising techniques for sustainable hydrogen production. However, the high salinity of seawater would deactivate catalysts and consume the photogenerated carriers. Metal vacancies in metal oxide semiconductors are critical to directed electron transfer and high salinity resistance; they are thus desirable but remain a challenge. We demonstrate a facile controllable calcination approach to synthesize TiO2 nanofibers with rich Ti vacancies with excellent photo/electro performances and long-time stability in photodriven seawater splitting, including photocatalysis and photo-electrocatalysis. Experimental measurements and theoretical calculations reveal the formation of titanium vacancies, as well as unidirectional electron trap and superior H+ adsorption ability for efficient charge transfer and resistance to corrosion by seawater. Therefore, atomic-/nanoscale characteristics and mechanism have been proposed to clarify the generation of titanium vacancies and the corresponding interfacial electron transfer.

9.
Chemistry ; 27(57): 14142, 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34590741

RESUMO

Invited for the cover of this issue are Xiao-Yu Yang and co-workers at Wuhan University of Technology, Heinrich-Heine-Universität Düsseldorf, University of the Witwatersrand, and Ben-Gurion University of the Negev. The image depicts Ti vacancies in TiO2 as powerful drivers of photo- and photo-electrocatalytic seawater splitting for hydrogen production. Read the full text of the article at 10.1002/chem.202101817.

10.
BMC Anesthesiol ; 21(1): 116, 2021 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-33853548

RESUMO

BACKGROUND: The intrathecal hyperbaric bupivacaine dosage for cesarean section is difficult to predetermine. This study aimed to develop a decision-support model using a machine-learning algorithm for assessing intrathecal hyperbaric bupivacaine dose based on physical variables during cesarean section. METHODS: Term parturients presenting for elective cesarean section under spinal anaesthesia were enrolled. Spinal anesthesia was performed at the L3/4 interspace with 0.5% hyperbaric bupivacaine at dosages determined by the anesthesiologist. A spinal spread level between T4-T6 was considered the appropriate block level. We used a machine-learning algorithm to identify relevant parameters. The dataset was split into derivation (80%) and validation (20%) cohorts. A decision-support model was developed for obtaining the regression equation between optimized intrathecal 0.5% hyperbaric bupivacaine volume and physical variables. RESULTS: A total of 684 parturients were included, of whom 516 (75.44%) and 168 (24.56%) had block levels between T4 and T6, and less than T6 or higher than T4, respectively. The appropriate block level rate was 75.44%, with the mean bupivacaine volume [1.965, 95%CI (1.945,1.984)]ml. In lasso regression, based on the principle of predicting a reasonable dose of intrathecal bupivacaine with fewer physical variables, the model is "Y=0.5922+ 0.055117* X1-0.017599*X2" (Y: bupivacaine volume; X1: vertebral column length; X2: abdominal girth), with λ 0.055, MSE 0.0087, and R2 0.807. CONCLUSIONS: After applying a machine-learning algorithm, we developed a decision model with R2 0.8070 and MSE due to error 0.0087 using abdominal girth and vertebral column length for predicting the optimized intrathecal 0.5% hyperbaric bupivacaine dosage during term cesarean sections.


Assuntos
Algoritmos , Anestesia Obstétrica , Raquianestesia , Bupivacaína/administração & dosagem , Técnicas de Apoio para a Decisão , Aprendizado de Máquina , Adulto , Anestésicos Locais/administração & dosagem , Cesárea , Feminino , Humanos , Gravidez , Estudos Prospectivos
11.
Nano Lett ; 20(5): 3122-3129, 2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32343586

RESUMO

A highly efficient photoenergy conversion is strongly dependent on the cumulative cascade efficiency of the photogenerated carriers. Spatial heterojunctions are critical to directed charge transfer and, thus, attractive but still a challenge. Here, a spatially ternary titanium-defected TiO2@carbon quantum dots@reduced graphene oxide (denoted as VTi@CQDs@rGO) in one system is shown to demonstrate a cascade effect of charges and significant performances regarding the photocurrent, the apparent quantum yield, and photocatalysis such as H2 production from water splitting and CO2 reduction. A key aspect in the construction is the technologically irrational junction of Ti-vacancies and nanocarbons for the spatially inside-out heterojunction. The new "spatial heterojunctions" concept, characteristics, mechanism, and extension are proposed at an atomic-/nanoscale to clarify the generation of rational heterojunctions as well as the cascade electron transfer.

12.
Zhongguo Zhong Yao Za Zhi ; 46(1): 33-40, 2021 Jan.
Artigo em Zh | MEDLINE | ID: mdl-33645048

RESUMO

Berberine is the main extract of Coptis chinensis, and its anti-inflammatory, antioxidant, antibacterial and immunomodulatory effects have been confirmed by modern studies. Ulcerative colitis(UC) is a chronic, idiopathic inflammatory bowel disease with unknown etiology. Its causes involve genetics, intestinal microecology and mucosal immune system disorders. In this paper, literatures on relevant pathways and mechanism of berberine on ulcerative colitis in recent years were consulted and summarized to provide me-thods and ideas for developing berberine in the treatment of UC and exploring the mechanisms. The results showed that berberine protects the intestinal mucosal barrier, restores the body's normal immune response, and improves oxidative stress by regulating multiple signaling pathways, such as JAK-STAT, NK-κB, PI3 K-AKT, MAPK, Nrf2, ERS, and MLCK-MLC, so as to treat UC.


Assuntos
Berberina , Colite Ulcerativa , Colite , Berberina/farmacologia , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/genética , Humanos , Mucosa Intestinal , Transdução de Sinais
13.
Cancer Control ; 27(1): 1073274820904702, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33047615

RESUMO

This study aimed to review clinical experiences using whole-field simultaneous integrated boost (SIB) intensity-modulated radiotherapy (IMRT) and sequential IMRT in postoperative patients with oral cavity cancer (OCC). From November 2006 to December 2014, a total of 182 postoperative patients with OCC who underwent either SIB-IMRT (n = 63) or sequential IMRT (n = 119) were enrolled retrospectively and matched randomly according to multiple risk factors by a computer. The differences were well balanced after patient matching (P = .38). The median follow-up time was 65 months. For patients treated with the SIB technique and the sequential technique, the respective mortality rates were 36.8% and 20.0% (P = .04). The primary recurrence rates were 26.3% and 10.0% (P = .02), respectively. The respective marginal failure rates were 26.7% and 16.7%. A multivariate logistic regression analysis showed that patients who received the SIB technique had a 2.74 times higher risk of death than those who received the sequential technique (95% confidence interval = 1.10-6.79, P = .03). Sequential IMRT provided a significantly lower dose to the esophagus (5.2 Gy, P = .02) and trachea (4.6 Gy, P = .03) than SIB-IMRT. For patients with locally advanced OCC, postoperative sequential IMRT may overcome an unpredictable geographic miss, potentially with a lower marginal failure rate in the primary area. Patients treated by sequential IMRT show equal overall survival benefits to those treated by SIB-IMRT and a lower mortality rate than those treated by SIB-IMRT. Additionally, a reduced dose to the esophagus and trachea compared to sequential IMRT was noted.


Assuntos
Neoplasias Bucais/radioterapia , Fracionamento da Dose de Radiação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/mortalidade , Neoplasias Bucais/patologia , Estadiamento de Neoplasias , Cuidados Pós-Operatórios , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Radioterapia de Intensidade Modulada/mortalidade , Eficiência Biológica Relativa , Estudos Retrospectivos , Taxa de Sobrevida
14.
BMC Musculoskelet Disord ; 21(1): 264, 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32316949

RESUMO

BACKGROUND: We designed the current study to understand the normal trajectories of interleukin-6 (IL-6) and C-reactive protein (CRP) in the immediate hours and days after primary total knee arthroplasty (TKA) under the management of an enhanced recovery after surgery (ERAS) protocol and examined whether one or the other returned to normal more quickly. METHODS: In this prospective cross-sectional study, we examined the plasma IL-6 and CRP levels in 100 patients undergoing primary TKA at the following time points: 12 h preoperatively as well as postoperatively 12 h, 48 h, 3 days and 2 weeks. Patients were followed up for 1 year to monitor the postoperative complications, especially the infection. RESULTS: IL-6 peaked at 48 h postoperatively. Then IL-6 started to decline at 3 days postoperatively and went back to baseline level at 2 weeks (p = 0.950). CRP peaked at 3 days postoperatively. At 2 weeks, CRP declined to a normal range, without being significantly different from the baseline level (p = 0.816). CONCLUSION: We found that under the ERAS scenario, the postoperative peak of IL-6 and CRP was deferred compared with previous studies. Compared to IL-6, CRP showed a gradual rise after surgery. Both of these two biomarkers returned to normal under the ERAS scenario. Future multiple-center studies with larger sample size can help define the thresholds of IL-6 and CRP for periprosthetic joint infection (PJI) early diagnosis. With these reference data, a clinician can make a quicker decision to perform aspiration to diagnose early PJI and benefits more patients.


Assuntos
Artroplastia do Joelho , Proteína C-Reativa/metabolismo , Mediadores da Inflamação/sangue , Interleucina-6/sangue , Osteoartrite do Joelho/cirurgia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/sangue , Período Perioperatório , Estudos Prospectivos
15.
Mikrochim Acta ; 187(4): 255, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32239351

RESUMO

We report the first use of metallic nanozyme as colorimetric probe for Pb2+ determination. The method is based on the surface leaching of Au@PtNP nanozyme by Pb2+-S2O32- ions, accompanied by a decreased catalytic activity of the metallic nanozyme. To construct this colorimetric determination, the Pt deposition onto the AuNPs was carefully investigated and other experimental factors including kind of substrate and buffer were optimized. With increasing Pb2+ concentration, the catalytic activity of the Au@PtNPs decreased gradually. As a result, the blue color at 650 nm from the oxidation of 3,3',5,5'-tetramethylbenzidine by H2O2 faded gradually. A determination limit of 3.0 nM Pb2+ with a linear range from 20 to 800 nM was obtained. The assay demonstrated negligible response to common metal ions even at elevated concentrations. This colorimetric method was applied to the determination of Pb2+ ions spiked in lake water samples, and good recoveries (96.8-105.2%) were obtained. The above results indicate the potential application of metallic nanozymes in developing robust colorimetric assays. Graphical abstract Schematic representation of the surface leaching of Au@PtNP nanozyme by Pb2+-S2O32- ions, accompanying the decreased catalytic activity of the metallic nanozyme.


Assuntos
Colorimetria/métodos , Chumbo/análise , Nanopartículas Metálicas/química , Benzidinas/química , Catálise , Compostos Cromogênicos/química , Ouro/química , Peróxido de Hidrogênio/química , Lagos/análise , Chumbo/química , Oxirredução , Platina/química , Tiossulfatos/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química
16.
J Nat Prod ; 82(8): 2229-2237, 2019 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-31397570

RESUMO

Eleven new meroterpenoids, bipolahydroquinones A-C (1-3), cochlioquinones I-N (4-8 and 11), and isocochlioquinones F and G (9 and 10), together with six known ones, were obtained from an endophytic fungus Bipolaris sp. L1-2 from Lycium barbarum. Compound 2 is the first example of cochlioquinone derivatives possessing a benzofuran moiety. The structures and absolute configurations of the new compounds were elucidated by spectroscopic data interpretation, single-crystal X-ray diffraction analysis, chemical transformations, and biosynthetic considerations. Compounds 3, 4, and 6-8 showed cytotoxicity against NCI-H226 and/or MDA-MB-231 with IC50 values ranging from 5.5 to 9.5 µM.


Assuntos
Ascomicetos/química , Lycium/microbiologia , Monoterpenos/química , Monoterpenos/farmacologia , Cristalografia por Raios X , Estrutura Molecular , Análise Espectral/métodos , Estereoisomerismo
17.
Zhongguo Zhong Yao Za Zhi ; 44(4): 696-702, 2019 Feb.
Artigo em Zh | MEDLINE | ID: mdl-30989881

RESUMO

As a rare endangered medical plant that newly cultivated,little experimental information is available for growth and metabolites of Tetrastigma hemsleyanum in response to nitrogen( N). The effects of different levels of N on growth of T. hemsleyanum and the content of phytochemicals( polysaccharide,total flavonoids and phenolics) and antioxidant activity( ABTS and FRAP) in stems and leaves were investigated in this study. A certain amount of N had positive effects on most of biological traits,and excessive dose of N went against growth of T. hemsleyanum. With N levels decreased,the polysaccharide content in stems and leaves had no significant change,while the total flavonoid and phenolic content,and antioxidant activities increased steadily. Antioxidant activities and total flavonoid and phenolic content had significant positive correlation. Excessive N fertilizer should be avoided by cultivation.


Assuntos
Vitaceae , Antioxidantes , Flavonoides , Nitrogênio , Fenóis , Compostos Fitoquímicos , Extratos Vegetais , Folhas de Planta
18.
Oncologist ; 23(12): 1426-1435, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29728468

RESUMO

BACKGROUND: The purpose of this study was to review the risks and benefits of concurrent chemoradiation therapy (CCRT) with esophageal self-expandable metal stents (SEMS) for the treatment of locally advanced esophageal cancer. MATERIALS AND METHODS: Between January 2014 and December 2016, the data from 46 locally advanced esophageal cancer patients who received CCRT at our institution were retrospectively reviewed. Eight patients who received CCRT concomitant with SEMS placement (SEMS plus CCRT group) and thirty-eight patients who received CCRT without SEMS placement (CCRT group) were identified. The risk of developing esophageal fistula and the overall survival of the two groups were analyzed. RESULTS: The rate of esophageal fistula formation during or after CCRT was 87.5% in the SEMS plus CCRT group and 2.6% in the CCRT group. The median doses of radiotherapy in the SEMS plus CCRT group and the CCRT group were 47.5 Gy and 50 Gy, respectively. SEMS combined with CCRT was associated with a greater risk of esophageal fistula formation than CCRT alone (hazard ratio [HR], 72.30; 95% confidence interval [CI], 8.62-606.12; p < .001). The median overall survival times in the SEMS plus CCRT and CCRT groups were 6 months and 16 months, respectively. Overall survival was significantly worse in the SEMS plus CCRT group than in the CCRT group (HR, 5.72; 95% CI, 2.15-15.21; p < .001). CONCLUSION: CCRT concomitant with SEMS for locally advanced esophageal cancer results in earlier life-threatening morbidity and a higher mortality rate than treatment with CCRT alone. Further prospective and randomized studies are warranted to confirm these observations. IMPLICATIONS FOR PRACTICE: Patients treated with SEMS placement followed by CCRT had higher risk of esophageal fistula formation and inferior overall survival rate compared with patients treated with CCRT alone. SEMS placement should be performed cautiously in patients who are scheduled to receive CCRT with curative intent.


Assuntos
Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/radioterapia , Terapia Combinada/métodos , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/radioterapia , Stents/normas , Idoso , Quimiorradioterapia/métodos , Neoplasias Esofágicas/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
19.
Microb Ecol ; 76(3): 660-667, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29500492

RESUMO

Previous studies of acetate-promoted bioremediation of uranium-contaminated aquifers focused on Geobacter because no other microorganisms that can couple the oxidation of acetate with U(VI) reduction had been detected in situ. Monitoring the levels of methyl CoM reductase subunit A (mcrA) transcripts during an acetate-injection field experiment demonstrated that acetoclastic methanogens from the genus Methanosarcina were enriched after 40 days of acetate amendment. The increased abundance of Methanosarcina corresponded with an accumulation of methane in the groundwater. In order to determine whether Methanosarcina species could be participating in U(VI) reduction in the subsurface, cell suspensions of Methanosarcina barkeri were incubated in the presence of U(VI) with acetate provided as the electron donor. U(VI) was reduced by metabolically active M. barkeri cells; however, no U(VI) reduction was observed in inactive controls. These results demonstrate that Methanosarcina species could play an important role in the long-term bioremediation of uranium-contaminated aquifers after depletion of Fe(III) oxides limits the growth of Geobacter species. The results also suggest that Methanosarcina have the potential to influence uranium geochemistry in a diversity of anaerobic sedimentary environments.


Assuntos
Acetatos/metabolismo , Água Subterrânea/microbiologia , Methanosarcina/metabolismo , Urânio/metabolismo , Poluentes Químicos da Água/metabolismo , Biodegradação Ambiental , Geobacter/crescimento & desenvolvimento , Geobacter/metabolismo , Água Subterrânea/química , Metano/análise , Methanosarcina/genética , Methanosarcina/crescimento & desenvolvimento , Oxirredução , Urânio/análise , Poluentes Químicos da Água/análise
20.
BMC Vet Res ; 14(1): 378, 2018 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-30509251

RESUMO

BACKGROUND: Leishmania parasites cause visceral leishmaniasis (VL), an important infectious disease that is endemic to large parts of the world and often leads to epidemics. Sand flies are the primary transmission vector for the parasite in endemic regions. We hypothesized that sheep might serve as an overlooked reservoir for Leishmania transmission to humans due to the asymptomatic nature of infection in many species. As a preliminary test of this hypothesis, the aim of the present study was to investigate sheep in an area of China that is endemic for the desert sub-type of zoonotic VL and establish if they are potential carriers of Leishmania. RESULTS: Sheep tissue samples were collected from abattoirs in VL endemic areas of Jiashi County, China during the non-transmission season. rK39 immunochromatographic tests were performed to detect the presence of the parasite in blood samples. In addition, DNA was extracted from the blood, and used for detection of the Leishmania-specific internal transcribed spacer-1 (ITS-1) genomic region using a nested polymerase chain reaction (PCR) approach. PCR products were further analyzed to identify restriction fragment-length polymorphism patterns and representative sequences of each pattern were selected for phylogenetic analysis. The rK-39 and nested PCR data indicated positive detection rates for Leishmania in sheep of 26.32 and 54.39%, respectively. The phylogenetic analysis revealed that all of the samples belonged to the species L. infantum and were closely related to strains isolated from human infections in the same area. CONCLUSIONS: Sheep could be a potential host for Leishmania in VL endemic areas in China and may be an overlooked reservoir of human VL transmission in this region. To further confirm livestock as a potential host, further verification is required using a sand fly biting experiment.


Assuntos
Leishmania infantum/classificação , Leishmania infantum/fisiologia , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/parasitologia , Animais , China/epidemiologia , DNA Espaçador Ribossômico/genética , Especificidade de Hospedeiro , Humanos , Leishmania infantum/genética , Filogenia , Ovinos
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