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1.
Postgrad Med J ; 96(1134): 221-227, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32015189

RESUMO

Obesity is a growing chronic health problem worldwide. Studies about acupuncture for obesity treatment are many. But there are some doubts about the effectiveness of acupuncture versus sham acupuncture in treating obesity due to its lack of medical evidence. Therefore, the aim of this study is to assess the efficacy of acupuncture for obesity treatment and provide clinic evidence. Four English databases (PubMed, EMBASE, Web of Science and Cochrane Central Register of Controlled Trials) and four Chinese databases (China National Knowledge Infrastructure, Chinese BioMedical Database, Chinese Scientific Journal Database and Wan-Fang Data) were searched from their receptions to August 2019. Randomized controlled trials (RCTs) using the comparison between acupuncture and sham acupuncture to treat simple obesity were included. The primary outcome of body mass index (BMI) would be used to measure the effect of acupuncture on obesity. According to the trial data extraction form based on the Cochrane Handbook, two reviewers separately extracted the data. Risk of bias of the RCTs was assessed by the Cochrane Risk of Bias Tool. The study included 8 RCTs with 403 patients. When compared with sham acupuncture, acupuncture showed obviously effect in BMI reduction (MD=1.0kg/m2, 95% CI=0.6 to 1.4, P<0.001). There was also significant reduction in body weight (MD=1.85kg, 95%CI=0.82 to 2.88, p<0.001), WC (MD=0.97cm, 95%CI=0.24 to 1.71, p=0.01) and body fat mass percentage (MD=1.01, 95%CI=0.25 to 1.77, p<0.05). However, WHR (MD=0.01, 95%CI=0 to 0.03, p>0.05) was not statistically and significantly different between the acupuncture and control groups. Adverse effects were reported in 3 studies. The review suggests that acupuncture is an effective therapy for simple obesity rather than a placebo effect. This potential benefit needs to be further evaluated by longer-term and more rigorous RCTs.

2.
Plant Cell Environ ; 43(1): 275-291, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31703150

RESUMO

Although the alteration of DNA methylation due to abiotic stresses, such as exposure to the toxic metal cadmium (Cd), has been often observed in plants, little is known about whether such epigenetic changes are linked to the ability of plants to adapt to stress. Herein, we report a close linkage between DNA methylation and the adaptational responses in Arabidopsis plants under Cd stress. Exposure to Cd significantly inhibited the expression of three DNA demethylase genes ROS1/DML2/DML3 (RDD) and elevated DNA methylation at the genome-wide level in Col-0 roots. Furthermore, the profile of DNA methylation in Cd-exposed Col-0 roots was similar to that in the roots of rdd triple mutants, which lack RDD, indicating that Cd-induced DNA methylation is associated with the inhibition of RDD. Interestingly, the elevation in DNA methylation in rdd conferred a higher tolerance against Cd stress and improved cellular Fe nutrition in the root tissues. In addition, lowering the Fe supply abolished improved Cd tolerance due to the lack of RDD in rdd. Together, these data suggest that the inhibition of RDD-mediated DNA demethylation in the roots by Cd would in turn enhance plant tolerance to Cd stress by improving Fe nutrition through a feedback mechanism.

3.
J Hazard Mater ; 384: 121473, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31676164

RESUMO

The identification of the key genes related to cadmium (Cd) tolerance and accumulation is a major element in genetically engineering improved plants for Cd phytoremediation. Owing to the similarity between the ionic hydrated radius of Cd2+ and Fe2+, this study investigated how the Cd tolerance and accumulation of Arabidopsis plants was affected by the knockdown of BTS, a gene that negatively regulates Fe nutrition. After exposure to 40 µM Cd, the BTS-knockdown mutant, bts-1, exhibited greater Fe nutrition and better growth than wild-type plants. In addition, the Cd concentration in both roots and shoots was approximately 50% higher in the bts-1 mutant than in wild-type plants. Consequently, the bts-1 mutant accumulated approximately 100% and 150% more Cd in the roots and shoots, respectively, than wild-type plants. Further study showed that Fe removal from the growth medium and inhibition of the Fe transporter gene, IRT1, removed the differences observed in the growth and Cd concentration of the bts-1 and wild-type plants, respectively. These results demonstrated that BTS knockdown improved Cd tolerance and accumulation in plants by improving Fe nutrition; thus, the knockdown of BTS via biotechnological pathways may represent a valuable strategy for the improvement in the efficiency of Cd phytoremediation.

4.
Mediators Inflamm ; 2019: 8247019, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31827381

RESUMO

Background: High levels of branched-chain amino acids (BCAAs) and aromatic amino acids (AAAs) were associated with an increased risk of hyperglycemia and the onset of diabetes. This study is aimed at assessing circulating valine concentrations in subjects with type 2 diabetes (T2D) and in T2D patients and high-fat diet- (HFD-) fed mice treated with the hypoglycemic agent sitagliptin (Sit) and analyzing the association of valine concentrations with metabolic parameters. Methods: Metabolomics in HFD-fed mice were analyzed by gas chromatography-mass spectrometry (GC-MS) systems. Plasma valine concentrations were detected with a commercial kit in 53 subjects with normal glucose levels (n = 19), newly diagnosed T2D (n = 20), placebo-treated T2D (n = 7), or Sit-treated T2D (n = 7). Biochemical parameters were also assessed in all participants. Results: Sit treatment markedly changed the pattern of amino acid in HFD-fed mice, especially by reducing the level of the BCAA valine. Compared with the healthy controls, the plasma valine concentrations were significantly higher in the T2D patients (p < 0.05). Correlation analysis showed that the plasma valine concentration was positively correlated with the level of fasting plasma glucose (p < 0.05). Moreover, the plasma valine concentrations were notably reduced after Sit treatment in T2D patients (p < 0.05). Conclusions: Our findings demonstrate an important effect of Sit on the BCAA valine in T2D patients and HFD-fed mice, revealing a new hypoglycemic mechanism of it. Furthermore, the results suggest that the circulating valine level might be a novel biomarker for T2D and restoring the level of valine might be a potential strategy for diabetes therapy.

5.
Ying Yong Sheng Tai Xue Bao ; 30(11): 3911-3920, 2019 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-31833705

RESUMO

The index of relative importance (IRI), niche breadth, and niche overlap (Qik) of nekton species were calculated using data collected from four fishery resource surveys from May 2016 to February 2017 in Yueqing Bay, Zhejiang Province. The results showed that there were 27 major nekton species (IRI>100) with higher turnover rates across different seasons, while their niche breadth values differed greatly and showed significant positive correlation with IRI. The niche overlaps of nekton were generally low, with the highest overlap value in autumn and the lowest in spring. The total amount of species pairs with niche overlap over 0.6 (Qik>0.6) were 14 in the autumn and five in the spring, which represented 15.4% and 7.6% of the total pairs, respectively. Results from the redundancy analysis suggested that the distribution of main nekton species were mainly affected by temperature, salinity and turbidity, which cause ecological differentiation of nekton species.


Assuntos
Baías , Ecossistema , China , Pesqueiros , Estações do Ano
6.
Curr Med Sci ; 39(6): 899-905, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31845220

RESUMO

Absent in melanoma 2 (AIM2) inflammasome is a crucial link bridging the innate host defense and the subsequent adaptive immunity when activated by exogenous double stranded DNA (dsDNA). Through establishing models of disseminated murine cytomegalovirus (MCMV) infection in BALB/c and C57BL/6 mice, we evaluated dynamic expression of AIM2 inflammasome components and its relationship with pathological damage and viral replication, trying to figure out whether AIM2 inflammasome is related to the chronic mechanism of MCMV. BALB/c and C57BL/6 mice were sacrificed on day 0, 1, 3, 7, 14 and 28 post infection. Expression levels of AIM2, pro-caspase-1, caspase-1 p20, pro-IL1ß and mature IL1ß in primary peritoneal macrophages (PMs) and spleens were detected by Western blotting. Contents of IL18 in the serum were detected by ELISA. Pathological examinations of livers were performed, and mRNA levels of MCMV glycoprotein B (gB) in salivary glands also assessed. Results showed that expression levels of AIM2 in PMs and spleens of C57BL/6 mice increased on day 3, even continued to day 28; caspase-1 p20 and mature IL1ß increased on day 7, 14 and 28; the persistently high expression of IL18 in the serum started on day 1, showing a double peak curve. As for BALB/c mice, expression of AIM2 in PMs increased on day 1 and day 7, while contents of AIM2 in spleens increased on day 1 and day 3; caspase-1 p20 and mature IL1ß merely increased 7 days fter infection. Thereafter, expression levels of AIM2, caspase-1 p20, mature IL1ß and IL18 were limited; the duration of AIM2 inflammasome activation in BALB/c mice was much shorter than that in C57BL/6 mice. The severer pathological damage and more viral replications in BALB/c mice further proved the deficient antiviral immunity to MCMV. In conclusion, the activation of AIM2 inflammasome in BALB/c mice was short-lived, which is quite possibly related to the chronicity of MCMV infection.

7.
Medicine (Baltimore) ; 98(42): e17562, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31626121

RESUMO

BACKGROUND: Obesity is a growing chronic health problem worldwide. Studies about acupuncture for obesity treatment are many. But there are some doubts about the effectiveness of acupuncture vs sham acupuncture in treating obesity due to its lack of an evidence-based medical proof. Therefore, the aim of this study is to assess the efficacy of acupuncture for obesity treatment and provide clinic evidence. METHODS: This protocol was based on the previous reporting items for systematic review and meta-analysis agreements. Four English databases (PubMed, EMBASE, Web of Science, and Cochrane Central Register of Controlled Trials) and 4 Chinese databases (China National Knowledge Infrastructure, Chinese BioMedical Database, Chinese Scientific Journal Database, Wan-Fang Data) will be searched from their receptions to August 2019. Randomized controlled trials (RCTs) using acupuncture compared sham acupuncture (or no treatment) to treat simple obesity will be included. The primary outcome of body mass index (BMI) and body weight (BW) will be used to measure the effect of acupuncture on obesity. According to the trial data extraction form based on the Cochrane Handbook, 2 reviewers will separately extract the data. Risk of bias of the RCTs will be assessed by the Cochrane Risk of Bias Tool. Publication bias will be assessed with funnel plots. RESULTS: This study will be to evaluate whether acupuncture is an effective intervention for simple obesity when compared with sham acupuncture. CONCLUSION: The conclusion of this study will help clinicians provide effective treatment options for obese patients. ETHICS AND DISSEMINATION: Ethical approval is not required for systematic review and meta- analysis. The results of this review will be disseminated in a peer-review journal. PROSPERO REGISTRATION NUMBER: PROSPERO CRD42019129825.


Assuntos
Terapia por Acupuntura/métodos , Obesidade/terapia , Humanos , Resultado do Tratamento
8.
Biomolecules ; 9(9)2019 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-31480670

RESUMO

Tannins biodegradation by a microorganism is one of the most efficient ways to produce bioproducts of high value. However, the mechanism of tannins biodegradation by yeast has been little explored. In this study, Aureobasidium melanogenum T9 isolated from red wine starter showed the ability for tannins degradation and had its highest biomass when the initial tannic acid concentration was 20 g/L. Furthermore, the genes involved in the tannin degradation process were analyzed. Genes tan A, tan B and tan C encoding three different tannases respectively were identified in the A. melanogenum T9. Among these genes, tan A and tan B can be induced by tannin acid simultaneously at both gene transcription and protein expression levels. Our assay result showed that the deletion of tanA and tanB resulted in tannase activity decline with 51.3 ± 4.1 and 64.1 ± 1.9 U/mL, respectively, which is much lower than that of A. melanogenum T9 with 91.3 ± 5.8 U/mL. In addition, another gene coding gallic acid decarboxylase (gad) was knocked out to better clarify its function. Mutant Δgad completely lost gallic acid decarboxylase activity and no pyrogallic acid was seen during the entire cultivation process, confirming that there was a sole gene encoding decarboxylase in the A. melanogenum T9. These results demonstrated that tanA, tanB and gad were crucial for tannin degradation and provided new insights for the mechanism of tannins biodegradation by yeast. This finding showed that A. melanogenum has potential in the production of tannase and metabolites, such as gall acid and pyrogallol.

9.
Gen Comp Endocrinol ; 291: 113237, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31374285

RESUMO

The molecular mechanism underlying myostatin (MSTN)-regulated metabolic cross-talk remains poorly understood. In this study, we performed comparative proteomic and phosphoproteomic analyses of gluteus muscle tissues from MSTN-/- transgenic cattle using a shotgun-based tandem mass tag (TMT) 6-plex labeling method to explore the signaling pathway of MSTN in metabolic cross-talk and cellular metabolism during muscle development. A total of 72 differentially expressed proteins (DEPs) and 36 differentially expressed phosphoproteins (DEPPs) were identified in MSTN-/- cattle compared to wild-type cattle. Bioinformatics analyses showed that MSTN knockout increased the activity of many key enzymes involved in fatty acid ß-oxidation and glycolysis processes in cattle. Furthermore, comprehensive pathway analyses and hypothesis-driven AMP-activated protein kinase (AMPK) activity assays suggested that MSTN knockout triggers the activation of AMPK signaling pathways to regulate glucose and lipid metabolism by increasing the AMP/ATP ratio. Our results shed new light on the potential regulatory mechanism of MSTN associated with metabolic cross-talk in muscle development, which can be used in animal breeding to improve meat production in livestock animals, and can also provide valuable insight into treatments for obesity and diabetes mellitus in humans.

10.
Biomolecules ; 9(8)2019 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-31404957

RESUMO

Isomaltulose is mainly produced from sucrose by microbial fermentation, when the utilization of sucrose contributes a high production cost. To achieve a low-cost isomaltulose production, soy molasses was introduced as an alternative substrate. Firstly, α-galactosidase gene from Rhizomucor miehei was expressed in Yarrowia lipolytica, which then showed a galactosidase activity of 121.6 U/mL. Under the effects of the recombinant α-galactosidase, most of the raffinose-family oligosaccharides in soy molasses were hydrolyzed into sucrose. Then the soy molasses hydrolysate with high sucrose content (22.04%, w/w) was supplemented into the medium, with an isomaltulose production of 209.4 g/L, and the yield of 0.95 g/g. Finally, by virtue of the bioremoval process using Pichia stipitis, sugar byproducts in broth were transformed into ethanol at the end of fermentation, thus resulting in high isomaltulose purity (97.8%). The bioprocess employed in this study provides a novel strategy for low-cost and efficient isomaltulose production from soybean molasses.

11.
IEEE Trans Cybern ; 2019 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-31329145

RESUMO

With the increasing complexity and scale of activated sludge process (ASP), it is quite challenging to coordinate the performance indices with different time scales. To address this problem, a cooperative optimal controller (COC) is proposed to improve the operation performance in this paper. First, a cooperative optimal scheme is developed for designing the control system, where the different time-scale performance indices are formulated by two levels. Second, a data-driven surrogate-assisted optimization (DDSAO) algorithm is provided to optimize the cooperative objectives, where a surrogate model is established for evaluating the feasibility of optimal solutions based on the minimum squared error. Third, an adaptive predictive control strategy is investigated to derive the control laws for improving the tracking control performance. Finally, the proposed COC is tested on benchmark simulation model No. 1 (BSM1). The results demonstrate that the proposed COC is able to coordinate the multiple time-scale performance indices and achieve the competitive optimal control performance.

12.
Am J Transl Res ; 11(5): 2908-2924, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31217863

RESUMO

Current clinical approaches to treat irradiation-induced salivary gland hypofunction are ineffective. We previously reported that adipose-derived stem cell (ADSC)-based therapy ameliorates damaged salivary gland function in mice and that the effects were enhanced when the therapy was co-administrated with platelet-rich fibrin (PRF). We examined the feasibility of ADSC transdifferentiation into salivary gland acinar-like cells (SGALCs) and analyzed the potential of PRF to promote the transdifferentiation process in vitro. Salivary gland cells (SGCs) and ADSCs were indirectly co-cultured using Transwell inserts, and increasing concentrations of PRF-conditioned medium were applied to the co-culture system. The expression of α-amylase and AQP-5 were used to evaluate ADSC transdifferentiation. Notably, on day 7, 14, and 21, expression of both α-amylase and AQP-5 were detected in the co-cultured ADSCs. Additionally, PRF increased α-amylase and AQP-5 levels in ADSCs that were co-cultured for 7 days. These data demonstrate that ADSCs have the potential to transdifferentiate into SGALCs and that PRF can promote the transdifferentiation process. Therefore, these data reveal a possible mechanism to treat irradiation-induced salivary gland hypofunction and have translational medicine implications.

13.
J Orthop Surg Res ; 13(1): 326, 2018 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-30585142

RESUMO

BACKGROUND: Lumbar total disc replacement (TDR) has shown satisfactory clinical outcomes with few complications and reoperations at short-term follow-up, but the mid- to long-term results are not clear. PURPOSE: The objective of this study was to evaluate the mid- to long-term clinical outcomes of artificial TDR for lumbar degenerative disc diseases. PATIENTS AND METHODS: A systematic search was conducted using the PubMed database to identify studies of TDR surgery that included at least 3 years of follow-up. The search keywords were as follows: lumbar, total disc replacement, and arthroplasty. The following data were extracted: patient demographics, visual analogue scale (VAS) and Oswestry disability index (ODI) scores, satisfactory rate, clinical success rate, complications, and reoperations. RESULTS: Thirteen studies, including eight prospective studies and five retrospective studies, met the criteria. A total of 946 patients were identified who reported at least 3 years of follow-up results. The artificial prostheses in these studies were ProDisc-L, Charité, AcroFlex, Maverick, and XL TDR. Patients with lumbar TDR demonstrated significant improvements in VAS scores of 51.1 to 70.5% and of - 15.6 to - 44.4 for Oswestry disability index (ODI) scores at the last follow-up. Patient satisfaction rates were reported in eight studies and ranged from 75.5 to 93.3%. Complication rates were reported in 11 studies, ranging from 0 to 34.4%. The overall reoperation rate was 12.1% (119/986), ranging from 0 to 39.3%, with eight of the 13 studies reporting a reoperation rate of less than 10%. CONCLUSIONS: This review shows that lumbar TDR effectively results in pain relief and an improvement in quality of life at mid- to long-term follow-up. Complication and reoperation rates were acceptable. However, this study did not provide sufficient evidence to show that lumbar TDR is superior to fusion surgery. To answer that question, a greater number of high-quality randomized controlled trials (RCTs) are needed.


Assuntos
Degeneração do Disco Intervertebral/cirurgia , Vértebras Lombares/cirurgia , Substituição Total de Disco/métodos , Humanos , Degeneração do Disco Intervertebral/complicações , Dor Lombar/etiologia , Dor Lombar/cirurgia , Satisfação do Paciente , Qualidade de Vida , Reoperação/estatística & dados numéricos , Substituição Total de Disco/efeitos adversos
14.
Org Lett ; 20(19): 6022-6026, 2018 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-30221944

RESUMO

For the first time, a desymmetrization strategy empowered the assembly of a class of optically pure spirooxindole-urazoles possessing an N-Ar stereogenic axis via remote control of axial chirality in an asymmetric three-component reaction. This transformation was realized by a tandem bisthiourea-catalyzed asymmetric Diels-Alder reaction and substrate-controlled asymmetric ene reaction. The driving force derived from aromatization and the high reactivity of 4-aryl-1,2,4-triazole-3,5-dione enophiles mediated the occurrence of the successive ene reaction under mild conditions.

15.
Curr Med Sci ; 38(4): 632-639, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30128872

RESUMO

Increasing evidence has revealed that maternal cytomegalovirus (CMV) infection may be associated with neurodevelopmental disorders in offspring. Potential relevance between the placental inflammation and CMV-related autism has been reported by clinical observation. Meanwhile, abnormal expression of Toll-like receptor 2 (TLR2) and TLR4 in placenta of patients with chorioamnionitis was observed in multiple studies. IL-6 and IL-10 are two important maternal inflammatory mediators involved in neurodevelopmental disorders. To investigate whether murine CMV (MCMV) infection causes alterations in placental IL-6/10 and TLR2/4 levels, we analyzed the dynamic changes in gene expression of TLR2/4 and IL-6/10 in placentas following acute MCMV infection. Mouse model of acute MCMV infection during pregnancy was created, and pre-pregnant MCMV infected, lipopolysaccharide (LPS)-treated and uninfected mice were used as controls. At E13.5, E14.5 and E18.5, placentas and fetal brains were harvested and mRNA expression levels of placental TLR2/4 and IL-6/10 were analyzed. The results showed that after acute MCMV infection, the expression levels of placental TLR2/4 and IL-6 were elevated at E13.5, accompanied by obvious placental inflammation and reduction of placenta and fetal brain weights. However, LPS 50 µg/kg could decrease the EL-6 expression at E13.5 and E14.5. This suggests that acute MCMV infection during pregnancy could up-regulate the gene expression of TLR2/4 in placental trophoblasts and activate them to produce more proinflammatory cytokine IL-6. High dose of LPS stimulation (50 µg/kg) during pregnancy can lead to down-regulation of IL-6 levels in the late stage. Imbalance of IL-6 expression in placenta might be associated with the neurodevelopmental disorders in progeny.


Assuntos
Infecções por Herpesviridae/metabolismo , Placenta/metabolismo , Complicações Infecciosas na Gravidez/metabolismo , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Feminino , Infecções por Herpesviridae/genética , Interleucina-10/genética , Interleucina-10/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Gravidez , Complicações Infecciosas na Gravidez/genética , Receptor 2 Toll-Like/genética , Receptor 4 Toll-Like/genética , Regulação para Cima
16.
Asia Pac J Public Health ; 30(5): 491-499, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29992824

RESUMO

This study investigates the effectiveness of information technology-based 2-way referral in the diagnosis and management of cervical lesions in Minhang District, Shanghai, China. Women who underwent screening for cervical lesions in 4 community health centers constituted the intervention group, whereas women from the other 9 community health centers were included as controls. The diagnosis rate of cervical lesions was higher in the intervention group (7.61%) than in the control group (0.36%; P = .000). The diagnosis rate of early cervical lesion was 97.11% in the intervention group and 85.71% in the control group, showing no statistically significant differences ( P = .080). However, early diagnosis rate of precancerous lesion was much higher in the intervention group (95.45%) compared with the control group (64.29%; P = .001). In conclusion, higher effectiveness of early diagnosis and management of cervical lesions was observed in the intervention group compared with the control group.


Assuntos
Detecção Precoce de Câncer/estatística & dados numéricos , Tecnologia da Informação , Encaminhamento e Consulta/estatística & dados numéricos , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/terapia , Adulto , China , Centros Comunitários de Saúde , Feminino , Humanos , Pessoa de Meia-Idade
17.
Orthop Surg ; 10(2): 134-143, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29770581

RESUMO

OBJECTIVE: To evaluate how well different magnitudes of compression-induced degenerative changes using a bent rat tail model simulated human lumbar lordosis. It has been shown that compression plays an important role in intervertebral disc degeneration (IDD). METHODS: Sprague-Dawley rats (n = 25) were instrumented with a special compressive apparatus that was used to bend the intervertebral disc between the 8th and the 10th caudal vertebral bodies using two Kirschner wires inserted percutaneously into the middle of two tail vertebrae. Then, rats were divided into five different static compression loads (control, sham, 1.8 N, 4.5 N, and 7.2 N). The degeneration of the discs was evaluated by magnetic resonance imaging (MRI), histology, gene expression of anabolism and catabolism after 2 weeks. We used the signal characteristics of the disc in T2-weighted MRI to reflect the changes caused by degeneration as this is the most relevant and clinically recognized way to assess IDD. Pfirrmann classification was used to classify disc images. The tail discs from C8-9 and C9-10 with their two adjacent half vertebrae were carefully cut out and decalcified. Then the sections were paraffin-embedded and cut into 5-µm sections by histotome. Finally, they were stained with Safranin O-Fast Green and hematoxylin, and hematoxylin and eosin, respectively. Images were taken using a microscope and staining and compression-induced changes were assessed by a Masuda's grading scale. The relative expression levels of mRNA encoding rat anabolic genes and catabolic genes were evaluated by real-time reverse transcription (RT)-polymerase chain reaction (PCR). The mRNA expression fold change of the target gene was calculated using the 2-ΔΔCt method in the loaded and unloaded disc. RESULTS: As the loading magnitude increased, static compression produced a significantly progressive decrease in nucleus intensity on T2-weighted MRI, a decrease of aggrecan and Type II collagen, an increase in Matrix metallopeptidase-3 (MMP-3) and MMP-13 expressions, and a histomorphological degeneration. The sham group had a score of 1.4 ± 0.3, the 1.8 N group had a score of 2.4 ± 0.3, the 4.5 N group had a score of 3.2 ± 0.3, and the 7.2 N group had a score of 4.4 ± 0.3, which was based on the Pfirrmann classification score, in which the control group had a score of 1. These results demonstrated that the sham group was not significantly different from the control group. Histological analysis showed that in the loaded disc, the size of the nucleus was reduced and that the annular layer was disorganized. Based on the Masuda grading scale, scores were as follows: for the control group, 3.8 ± 0.35; sham, 4.2 ± 0.35; 1.8 N, 5.4 ± 0.35; 4.5 N, 7.6 ± 0.35; and 7.2 N, 10 ± 0.35. The gene expression was divided into the following: anabolic genes (aggrecan, collagen type1-α1, and collagen type2-α1) and catabolic genes (MMP-3 and MMP-13). Aggrecan and collagen type 2 were, respectively, downregulated from 0.42 ± 0.04 to 0.21 ± 0.04 and from 0.93 ± 0.06 to 0.17 ± 0.06 as the magnitude of compression increased, whereas collagen type 1 was significantly upregulated, from 2.49 ± 0.19 to 4.40 ± 0.19, when compared with the control group (from 1.8 to 7.2 N, P < 0.05). Catabolic genes MMP-3 and MMP-13 were significantly upregulated in all experimental groups (P < 0.05, MMP-3: from 1.46 ± 0.18 to 3.44 ± 0.18; MMP-13: from 1.19 ± 0.12 to 2.82 ± 0.13); however, MMP-13 exhibited no significant changes but tended to be upregulated when compared with the 1.8 N group with the 4.5 N group. CONCLUSIONS: Different stresses led to different processes of degenerative changes, the concave disc degenerating more severely as stress gradually increased.


Assuntos
Degeneração do Disco Intervertebral/fisiopatologia , Disco Intervertebral/fisiopatologia , Agrecanas/biossíntese , Agrecanas/genética , Animais , Cauda Equina/diagnóstico por imagem , Cauda Equina/fisiopatologia , Colágeno/biossíntese , Colágeno/genética , Modelos Animais de Doenças , Regulação da Expressão Gênica/fisiologia , Disco Intervertebral/diagnóstico por imagem , Disco Intervertebral/metabolismo , Degeneração do Disco Intervertebral/diagnóstico por imagem , Degeneração do Disco Intervertebral/metabolismo , Degeneração do Disco Intervertebral/patologia , Imagem por Ressonância Magnética , Metaloproteinase 13 da Matriz/biossíntese , Metaloproteinase 13 da Matriz/genética , Metaloproteinase 3 da Matriz/biossíntese , Metaloproteinase 3 da Matriz/genética , RNA Mensageiro/genética , Ratos Sprague-Dawley , Estresse Mecânico , Suporte de Carga
18.
Ying Yong Sheng Tai Xue Bao ; 29(1): 113-124, 2018 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-29692019

RESUMO

In order to investigate the effect of different colored plastic film mulching and planting density on spring maize dry matter accumulation and yield in the rain-fed area of the Northeast China, a complete combination field experiment which was comprised by three types of mulching (non-mulching, transparent plastic film mulching and black plastic film mulching) and five densities (60000, 67500, 75000, 82500 and 90000 plants·hm-2), was conducted to analyze the water and heat effect, dry matter accumulation and yield of spring maize (Liangyu 99). The results showed that, compared with the other mulching treatments, the black plastic film mulching treatment significantly increased the maize dry matter accumulation and maize biomass by 3.2%-8.2%. In mature stage, the biomass increased firstly and then decreased with the increasing plant density. When planting density was 82500 plants·hm-2, the biomass was the highest, which was 5.2%-28.3% higher than that of other plant density treatments. The mean soil temperature in prophase of transparent plastic film mulching treatment was 0.4-2.7 ℃ higher than that of other treatments, which accelerated the maize growth process and augmented the dry matter transportation amount (T), dry matter transportation efficiency (TE) and contribution rate of dry matter transportation to the grain yield (TC) of maize stalk and leaf. The T, TE, TC of leaf and leaf-stalk under 60000 plants·hm-2 treatment were the highest. The highest T, TE, TC of stalk were observed under 75000 plants·hm-2 treatment. In heading period, the water consumption and daily water consumption intensity of maize under the treatment of black film mulching were the largest, which were 9.4%-10.6% and 10.6%-24.5% higher than that of other mulching treatments, respectively. The highest water consumption and daily water consumption intensity were both obtained under 90000 plants·hm-2 treatment, which increased by 6.8%-15.7% and 7.0%-20.0% compared with other plant density treatments. The combination of black film mulching and density of 82500 plants·hm-2 significantly improved the water use efficiency of maize, which increased by 4.6%-40.9% compared with other treatments. In addition, it increased yield by 3.0%-39.7% compared with other treatments. At heading stage, the correlation between the dry matter amount of stalk and leaf and the yield and yield components was the biggest. Decreasing 1 kg·hm-2 dry matter amount of stalk and leaf would decrease the population yield by almost 0.79 kg·hm-2. Decreasing 10% dry matter amount of stalk and leaf would decrease the yield by almost 10%. Based on increasing plant density, black film mulching was beneficial for increasing the dry matter accumulation and improving grain yield and water use efficiency of spring maize.


Assuntos
Cor , Plásticos , Zea mays/crescimento & desenvolvimento , Agricultura , Biomassa , China , Produção Agrícola , Chuva , Solo , Água
19.
Dalton Trans ; 47(15): 5286-5297, 2018 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-29569676

RESUMO

Density functional theory (DFT) calculations were used to study the ruthenium porphyrin-catalyzed oxidation of styrene to generate an aldehyde. The results indicate that two reactive oxidants, dioxoruthenium and monooxoruthenium-superoxo porphyrins, participate in the catalytic oxidation. In the mechanism, the resultant monooxoruthenium porphyrin acts in the tandem epoxide isomerization (E-I) to selectively yield an aldehyde and generate a dioxoruthenium porphyrin, thereby triggering new oxidation reaction cycles. In this calculation, several key elements responsible for the observed oxidative ability have been established by using Frontier molecular orbital (FMO) theory, natural bond orbital (NBO) analysis, etc., which include the reaction energy, the spin exchange effect, the spin-state conversion process, and the energy level of the lowest unoccupied molecular orbitals (LUMOs) of the reactive oxidants. The comparative oxidative abilities of the ruthenium-oxo/superoxo compounds with different axial ligands are also investigated. The results suggest that the ruthenium-oxo/superoxo species featuring a chlorine axial ligand is more reactive than that substituted with oxygen. This tuneable reactivity can be understood when considering the different electronic characters of the two ligands and the effective atomic number rule (EAN).

20.
Acta Pharmacol Sin ; 39(8): 1393-1404, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29417949

RESUMO

Cryptotanshinone (CT) is the main active component in the root of Salvia miltiorrhiza Bunge (SMB) that displays antibacterial, anti-inflammatory and anticancer activities. In this study, we characterized phase I and phase II metabolism of CT in human liver microsomes in vitro and identified the metabolic enzymes (CYPs and UGTs) involved. The metabolites of CT generated by CYPs were detected using LC-MS/MS and the CYP subtypes involved in the metabolic reactions were identified using chemical inhibitors of CYP enzymes and recombinant human CYP enzymes (CYP1A2, CYP2A6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, and CYP3A4). Glucuronidation of CT was also examined, and the UGT subtypes involved in the metabolic reactions were identified using recombinant human UGT enzymes (1A1, 1A3, 1A4, 1A5, 1A6, 1A7, 1A8, 1A9, 1A10, 2B4, 2B7, 2B15 and 2B17). After adding NADPH to the human liver microsomes incubation system, CT was transformed into 6 main dehydrogenation and hydroxylation metabolites. CYP2A6, CYP3A4 and CYP2C19 were the major contributors to the transformation of its hydroxylation metabolites. CYP2C19, CYP1A2 and CYP3A4 were the major contributors to the transformation of its hydrogenation metabolites in human liver microsomes. This study showed that the metabolites at m/z of 473 were mediated by UGT1A9 and that the metabolites at m/z of 489 were mediated by UGT2B7 and UGT2B4. CT was extensively metabolized by UGTs following metabolism by CYPs in the liver.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Glucuronosiltransferase/metabolismo , Fenantrenos/metabolismo , Inibidores das Enzimas do Citocromo P-450/farmacologia , Ensaios Enzimáticos , Glucuronídeos/biossíntese , Glucuronídeos/química , Humanos , Microssomos Hepáticos/metabolismo , Estrutura Molecular , NAD(P)H Desidrogenase (Quinona)/metabolismo , Fenantrenos/química , Proteínas Recombinantes/metabolismo
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