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1.
J Exp Bot ; 2019 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-31420662

RESUMO

The non-protein gamma-aminobutyric acid (GABA) rapidly accumulates in plant tissues in response to salinity. However, the physiological rationale beyond this elevation remains elusive. This study compared electrophysiological and whole-plant responses of salt-treated Arabidopsis thaliana mutants pop2-5 and gad1,2 that possess different abilities for GABA accumulation. The pop2-5 mutant that was capable to over-accumulate GABA in its roots showed a salt-tolerant phenotype. On the contrary, gad1,2 mutant lacking an ability for conversion of glutamate to GABA showed over-sensitivity to salinity. The differential salinity tolerance between two lines was explained by: (1) the role of GABA in the stress-induced activation of H+-ATPase thus leading to better membrane potential maintenance and reduced extent of stress-induced K+ leak from roots; (2) reduced rates of net Na+ uptake in pop2-5 roots; (3) higher expression of SOS1 and NHX1 genes in leaves of salt-tolerant pop2-5 plants, which contributed to reducing Na+ concentration in the cytoplasm by excluding Na+ to apoplast and sequestering Na+ in vacuole; (4) lower rate of H2O2 production and reduced ROS-inducible K+ efflux from root epidermis in the tolerant line; and (5) better K+ retention in the shoot associated with the lower expression level of GORK channels in plant leaves.

2.
Biochemistry ; 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31448595

RESUMO

The average conformation of the methyl-branched chains of archaeal lipid phosphatidyl glycerophosphate methyl ester (PGP-Me) was examined in a hydrated bilayer membrane based on the 2H nuclear magnetic resonance (NMR) of enantioselectively 2H-labeled compounds that were totally synthesized for the first time in this study. The NMR results in combination with molecular dynamics simulations revealed that the PGP-Me chain appeared to exhibit behavior different from that of typical membrane lipids such as dimyristoylphosphatidylcholine (DMPC). The C-C bonds of the PGP-Me chain adopt alternative parallel and tilted orientations to the membrane normal as opposed to a DMPC chain where all of the C-C bonds tilt in the same way on average. This characteristic orientation causes the intertwining of PGP-Me chains, which plays an important role in the excellent thermal and high-salinity stabilities of archaeal lipid bilayers and membrane proteins.

3.
Ecotoxicol Environ Saf ; 183: 109571, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31446170

RESUMO

The molecular mechanisms of the differences among the Cd tolerance and accumulation of different pak choi cultivars are essential to further breed Cd-safe genotypes pak choi. In our research, via morphological comparison, qRT-PCR and yeast function complementary approaches, we explored the differences of Cd tolerance and capacity for Cd uptake in nine various pak choi varieties. Results showed that higher expressions of BcZIPs involved in Cd uptake in 'Kang Re605' may lead to its higher capacity for Cd accumulation. The lowest expressions of transporter gene in 'Wu Yueman' were consistent with its fewest ability to uptake Cd. Beyond that, the difference of resistance was very great among varieties. Meanwhile, the expressions of the BcGSTUs were differentially induced by Cd exposure in different pak choi varieties, and 'Kang Re605' performed the highest BcGSTUs expression overall. To verify the role of GSTUs played in Cd resistance of pak choi, four BcGSTUs, BcGSTU4, BcGSTU11, BcGSTU12 and BcGSTU22 in a high-Cd accumulation and tolerance variety 'Kang Re605' were cloned, quantitated and transferred to Cd-sensitive yeast mutant strain. And finally found that BcGSTU11 increased the Cd tolerance of yeast, which may associate with a high Cd resistance of 'Kang Re605'. Simultaneously, less BcGSTUs abundance in 'Shang Haiqing' may result in its weak tolerance to Cd. These findings will help us to comprehend the roles of BcZIPs and BcGSTUs in Cd absorption and detoxification as well as promote our understanding of the Cd-resistant and Cd-accumulated mechanisms in pak choi.

4.
Sci Total Environ ; 695: 133596, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31421330

RESUMO

Trace metal contamination prevails in various compartments of the urban environment. Understanding the roles of various anthropogenic sources in urban trace metal contamination is critical for pollution control and city development. In this study, the source contribution from various contamination sources to trace metal contamination (e.g., Cu, Pb, Zn, Co, Cr and Ni) in different environmental compartments in a typical megacity, Guangzhou, southern China, was investigated using the receptor model (Absolute Principal Component Scores-Multiple Linear Regression, APCS-MLR) coupled with the Kriging technique. Lead isotopic data and APCS-MLR analysis identified industrial and traffic emissions as the major sources of trace metals in surface soil, road dust, and foliar dust in Guangzhou. Lead isotopic compositions of road dust and foliar dust exhibited similar ranges, implying their similar sources and potential metal exchange between them. Re-suspended soil contributed to 0-38% and 25-58% of the trace metals in the road dust and foliar dust, respectively, indicating the transport of the different terrestrial dust. Spatial distribution patterns implied that Cu in the road dust was a good indicator of traffic contamination, particularly with traffic volume and vehicle speed. Lead and Zn in foliar dust indicated mainly industrial contamination, which decreased from the emission source (e.g., a power plant and steel factory) to the surrounding environment. The spatial influence of industry and traffic on the contamination status of road dust/foliar dust was successfully separated from that of other anthropogenic sources. This study demonstrated that anthropogenic inputs of trace metals in various environmental compartments (e.g., urban soil, road dust, and foliar dust) can be evaluated using a combined APCS-MLR receptor model and geostatistical analysis at a megacity scale. The coupled use of APCS-MLR analysis, geostatistics, and Pb isotopes successfully deciphered the spatial influence of the contamination sources in the urban environment matrix, providing some important information for further land remediation and health risk assessment.

5.
Sci Rep ; 9(1): 10449, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31320654

RESUMO

Validity conditions for the adiabatic approximation are useful tools to understand and predict the quantum dynamics. Remarkably, the resonance phenomenon in oscillating quantum systems has challenged the adiabatic theorem. In this scenario, inconsistencies in the application of quantitative adiabatic conditions have led to a sequence of new approaches for adiabaticity. Here, by adopting a different strategy, we introduce a validation mechanism for the adiabatic approximation by driving the quantum system to a non-inertial reference frame. More specifically, we begin by considering several relevant adiabatic approximation conditions previously derived and show that all of them fail by introducing a suitable oscillating Hamiltonian for a single quantum bit (qubit). Then, by evaluating the adiabatic condition in a rotated non-inertial frame, we show that all of these conditions, including the standard adiabatic condition, can correctly describe the adiabatic dynamics in the original frame, either far from resonance or at a resonant point. Moreover, we prove that this validation mechanism can be extended for general multi-particle quantum systems, establishing the conditions for the equivalence of the adiabatic behavior as described in inertial or non-inertial frames. In order to experimentally investigate our method, we consider a hyperfine qubit through a single trapped Ytterbium ion 171Yb+, where the ion hyperfine energy levels are used as degrees of freedom of a two-level system. By monitoring the quantum evolution, we explicitly show the consistency of the adiabatic conditions in the non-inertial frame.

6.
JAMA Intern Med ; 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31355870

RESUMO

Importance: The effects of acupuncture as adjunctive treatment to antianginal therapies for patients with chronic stable angina are uncertain. Objective: To investigate the efficacy and safety of acupuncture as adjunctive therapy to antianginal therapies in reducing frequency of angina attacks in patients with chronic stable angina. Design, Setting, and Participants: In this 20-week randomized clinical trial conducted in outpatient and inpatient settings at 5 clinical centers in China from October 10, 2012, to September 19, 2015, 404 participants were randomly assigned to receive acupuncture on the acupoints on the disease-affected meridian (DAM), receive acupuncture on the acupoints on the nonaffected meridian (NAM), receive sham acupuncture (SA), and receive no acupuncture (wait list [WL] group). Participants were 35 to 80 years of age with chronic stable angina based on the criteria of the American College of Cardiology and the American Heart Association, with angina occurring at least twice weekly. Statistical analysis was conducted from December 1, 2015, to July 30, 2016. Interventions: All participants in the 4 groups received antianginal therapies as recommended by the guidelines. Participants in the DAM, NAM, and SA groups received acupuncture treatment 3 times weekly for 4 weeks for a total of 12 sessions. Participants in the WL group did not receive acupuncture during the 16-week study period. Main Outcomes and Measures: Participants used diaries to record angina attacks. The primary outcome was the change in frequency of angina attacks every 4 weeks from baseline to week 16. Results: A total of 398 participants (253 women and 145 men; mean [SD] age, 62.6 [9.7] years) were included in the intention-to-treat analyses. Baseline characteristics were comparable across the 4 groups. Mean changes in frequency of angina attacks differed significantly among the 4 groups at 16 weeks: a greater reduction of angina attacks was observed in the DAM group vs the NAM group (difference, 4.07; 95% CI, 2.43-5.71; P < .001), in the DAM group vs the SA group (difference, 5.18; 95% CI, 3.54-6.81; P < .001), and in the DAM group vs the WL group (difference, 5.63 attacks; 95% CI, 3.99-7.27; P < .001). Conclusions and Relevance: Compared with acupuncture on the NAM, SA, or no acupuncture (WL), acupuncture on the DAM as adjunctive treatment to antianginal therapy showed superior benefits in alleviating angina. Trial Registration: ClinicalTrials.gov identifier: NCT01686230.

7.
Lab Invest ; 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31292540

RESUMO

Growth differentiation factor 11 (GDF11) is a transforming growth factor ß superfamily member with a controversial role in rejuvenating old stem cells after acute injury in the elderly population. This study aimed to evaluate the effects of telomerase reverse transcriptase (TERT) on GDF11-mediated rejuvenation of senescent late-outgrowth endothelial progenitor cells (EPCs), defined as VEGFR2+/CD133+ cells, in elderly patients with acute myocardial infarction (AMI). We compared the quantity and capabilities of VEGFR2+/CD133+ cells from old (>60 years), middle-aged (45-60 years), and young (<45 years) AMI patients. The decline in circulating count and survival of VEGFR2+/CD133+ cells with age was accompanied by decrease in their TERT and GDF11 expression levels in patients with AMI. Further, upregulation of TERT could trigger GDF11-mediated rejuvenation of old VEGFR2+/CD133+ cells by renewing their survival and angiogenic abilities through activation of canonical (Smad2/3) and noncanonical (eNOS) signaling pathways. Depletion of GDF11 or TERT caused senescence of young VEGFR2+/CD133+ cells leading to impaired vascular function and angiogenesis in vitro and in vivo, whereas adTERT and rhGDF11 rescued this senescence. TERT cooperates with GDF11 to enhance regenerative capabilities of old VEGFR2+/CD133+ cells. When combined with TERT, GDF11 may represent a potential therapeutic target for the treatment of elderly patients with MI.

8.
Math Biosci Eng ; 16(4): 2549-2561, 2019 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-31137227

RESUMO

Preventing the infectious disease from breakout and maintaining public health have always been placed at the first place when making public healthy policy. When the epidemic trend of infectious disease arises, compulsory treatment is an efficient pattern to control the rapid spreading. A sliding mode is carried out to evaluate the effect of compulsory treatment in the infectious disease controlling. When the number of infected persons reach a certain level Ic, the policy of compulsory treatment will be carried out at rate f . We analyze the influence of the compulsory treatment rate f and threshold value Ic to commence the control. Finally we investigate the theorems and the existence of the optimality combination.

9.
Environ Pollut ; 251: 45-55, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31071632

RESUMO

Hydrogen gas (H2) has been shown as an important factor in plant tolerance to abiotic stresses, but the underlying mechanisms remain unclear. In the present study, the effects of H2 and its interaction with nitric oxide (NO) on alleviating cadmium (Cd) stress in Brassica campestris seedlings were investigated. NO donor (SNP) or hydrogen-rich water (HRW) treatment showed a significant improvement in growth of Cd-stressed seedlings. Cd treatment upregulated both endogenous NO and H2 (36% and 66%, respectively), and the increase of H2 was prior to NO increase. When treated with NO scavenger (PTIO) or NO biosynthesis enzyme inhibitors (L-NAME and Gln), HRW-induced alleviation under Cd stress was prevented. Under Cd stress, HRW pretreatment significantly enhanced the NO accumulation, and together up-regulated the activity of NR (nitrate reductase) and expression of NR. HRW induced lower reactive oxygen species (ROS), higher AsA content, enhanced activity of POD (peroxidase) and SOD (superoxide dismutase) in seedling roots were inhibited by PTIO, L-NAME and Gln. Through proteomic analysis, the level of 29 proteins were changed in response to H2 and NO-induced amelioration of Cd stress. Nearly half of them were involved in oxidation-reduction processes (about 20%) or antioxidant enzymes (approximately 20%). These results strongly indicate that in Cd-stressed seedlings, pretreatment with HRW induces the accumulation of H2 (biosynthesized or permeated), which further stimulates the biosynthesis of NO through the NR pathway. Finally, H2 and NO together enhance the antioxidant capabilities of seedlings in response to Cd toxicity.


Assuntos
Antioxidantes/metabolismo , Brassica/efeitos dos fármacos , Cádmio/toxicidade , Hidrogênio/farmacologia , Óxido Nítrico/biossíntese , Poluentes do Solo/toxicidade , Brassica/enzimologia , Brassica/metabolismo , Cádmio/metabolismo , Doadores de Óxido Nítrico/farmacologia , Oxirredução , Proteômica , Plântula/efeitos dos fármacos , Plântula/enzimologia , Plântula/metabolismo , Poluentes do Solo/metabolismo , Regulação para Cima/efeitos dos fármacos
10.
Ecotoxicol Environ Saf ; 177: 47-57, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30959312

RESUMO

Hemin (ferroprotoporphyrin IX), a compound derivative of heme, has been shown to exert numerous beneficial physiological functions in the resistance of plant to various abiotic stresses. This work investigated the effects of hemin on ameliorating Cd toxicity in Chinese cabbage (Brassica chinensis L.). Our results showed that leaf chlorosis, growth inhibition, root morphology and photosynthetic activity were significantly improved by the addition of hemin in Cd-stressed plants. Meanwhile, Cd-induced oxidative damage was also alleviated by hemin, which was supported by the decreased level of malondialdehyde (MDA) in roots of the seedlings treated with hemin. In the same time, the activities of antioxidative enzymes, including superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT), as well as the concentrations of ascorbic acid (AsA) and glutathione (GSH) were elevated by hemin, which contributed to the scavenging of Cd-elicited H2O2 and O2•- within the roots of Chinese cabbage seedlings. Furthermore, compared with Cd stressed plants, Cd concentrations in both shoots and roots were markedly decreased by exogenous hemin. Hence, it can be speculated that hemin-mediated tolerance to Cd stress may be associated with the inhibition of Cd uptake in Chinese cabbage. This hypothesis was supported by the down-regulated expressions of transporter genes, including BcIRT1, BcIRT2, BcNramp1 and BcZIP2 caused by hemin addition in Chinese cabbage seedlings under Cd treatment. Taken together, these results suggested that hemin alleviated Cd toxicity probably through increasing antioxidative capacities and inhibiting Cd uptake of Chinese cabbage.


Assuntos
Antioxidantes/metabolismo , Brassica/efeitos dos fármacos , Cádmio/metabolismo , Hemina/farmacologia , Plântula/efeitos dos fármacos , Ácido Ascórbico/metabolismo , Transporte Biológico , Brassica/metabolismo , Cádmio/toxicidade , Catalase/metabolismo , Glutationa/metabolismo , Peróxido de Hidrogênio/metabolismo , Malondialdeído/metabolismo , Oxirredução , Peroxidase/metabolismo , Peroxidases/metabolismo , Superóxido Dismutase/metabolismo
11.
Zhen Ci Yan Jiu ; 44(2): 120-4, 2019 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-30945488

RESUMO

OBJECTIVE: To observe the effect of herbal-cake-partitioned moxibustion (HCPM) of "Shenque" (CV8) and "Daheng" (SP15) on abdominal pain, plasma ß-endorphin (ß-EP), uterine prostaglandin E2 (PGE2) and prostaglandin F2α (PGF2α) levels, as well as splenetic natural killer cell (NK cell) activity in primary dysmenorrhea (PD) rats, so as to explore the specificity of acupoint function and the underlying mechanisms of moxibustion in relieving dysmenorrhea. METHODS: A total of 40 female rats were randomized into blank control, model, CV8-direct moxibustion, CV8-HCPM and SP15-HCPM groups (n=8 rats in each). The PD model was established by subcutaneous injection of estradiol benzoate injection (0.2-0.5 mg/rat) for 10 consecutive days and intraperitoneal injection of oxytocin (2 U) 24 h after the last subcutaneous injection. Moxibustion or herbal-cake (composed of Radix Angelicae Sinensis, Rhizoma Chuanxiong, Radix Paeoniae Rubra, Cortex Cinnamomi, etc.)-partitioned moxibustion was applied to CV8, SP15 or umbilicus respectively for 7 moxa-cones every time, once daily for 10 successive days. The rats of the control and model groups were also restrained as those in the moxibustion groups. The writhing times within 30 minutes was recorded and the contents of plasma ß-EP, uterine PGE2 and PGF2α were detected by ELISA, and NK cell activity was detected using MTT. RESULTS: Compared with the control group, the writhing times and the content of PGF2α in the uterus tissue were significantly increased in the model group (P<0.01), while the contents of plasma ß-EP, uterine PGE2 and splenetic NK cell activity were significantly decreased (P<0.01). In comparison with the model group, the writhing times and uterine PGF2α content were obviously down-regulated in the SP15-HCPM, CV8-direct moxibustion and CV8-HCPM groups (P<0.05, P<0.01), and the contents of plasma ß-EP and uterine PGE2, and splenetic NK cell activity were significantly increased (P<0.05, P<0.01). The therapeutic effects of CV8-HCPM group were significantly superior to those of SP15-HCPM and CV8-direct moxibustion groups in lowering writhing times and PGF2α level, and in up-regulating ß-EP, PGE2 (P<0.05, P<0.01). The NK cell activity of CV8-HCPM group was significantly increased compared with that in the SP15-HCPM group(P<0.05). No significant differences were found between the SP15-HCPM and CV8-direct moxibustion groups in the levels of writhing times, plasma ß-EP and uterine PGE2, PGF2α contents and splenetic NK cell activity (P>0.05). CONCLUSION: Moxibustion of both CV8 and SP15 can relieve abdominal pain in PD rats, which may be closely associated with its effect in suppressing PD-induced decrease of plasma ß-EP and uterine PGE2 levels and splenetic NK cell activity and increase of uterine PGF2α. The therapeutic effect of CV8-HCPM is obviously better than that of SP15-HCPM and CV8-direct moxibustion.


Assuntos
Dor Abdominal , Moxibustão , Pontos de Acupuntura , Animais , Dismenorreia , Feminino , Ratos , beta-Endorfina
12.
Nano Lett ; 19(5): 3040-3048, 2019 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-30968694

RESUMO

Exosomes, also known as extracellular vesicles, are naturally occurring, biocompatible, and bioacive nanoparticles ranging from 40 to 150 nm in diameter. Bone-secreted exosomes play important roles in bone homeostasis, the interruption of which can lead to diseases such as osteoporosis, rheumatoid arthritis, and osteopetrosis. Though the relationship between vascular and bone homeostasis has been recognized recently, the role of vascular endothelial cell (EC)-secreted exosomes (EC-Exos) in bone homeostasis is not well understood. Herein, we found that EC-Exos show more efficient bone targeting than osteoblast-derived exosomes or bone marrow mesenchymal stem cell-derived exosomes. We also found that EC-Exos can be internalized by bone marrow-derived macrophages (BMMs) to alter their morphology. EC-Exos can inhibit osteoclast activity in vitro and inhibit osteoporosis in an ovariectomized mouse model. Sequencing of exosome miRNA revealed that miR-155 was highly expressed in EC-Exos-treated BMMs. The miR-155 level in EC-Exos was much higher than that in BMMs and ECs, indicating that miR-155 was endogenous cargo of EC-derived vesicles. Blockage of BMMs miR-155 levels reversed the suppression by EC-Exos of osteoclast induction, confirming that exosomal miR-155 may have therapeutic potential against osteoporosis. Taken together, our findings suggest that EC-Exos may be utilized as a bone targeting and nontoxic nanomedicine for the treatment of bone resorption disorders.

13.
Int J Mol Sci ; 20(7)2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30974873

RESUMO

Amino acids (AAs) are vital elements for growth, reproduction, and maintenance of organisms. Current technology uses genetically engineered microorganisms for AAs production, which has urged the search for a safer food-grade AA producer strain. The extracellular proteolytic activities of lactic acid bacteria (LAB) can be a vital tool to hydrolyze extracellular protein molecules into free AAs, thereby exhibiting great potential for functional AA production. In this study, eight LAB isolated from Malaysian foods were determined for their extracellular proteolytic activities and their capability of producing AAs. All studied LAB exhibited versatile extracellular proteolytic activities from acidic to alkaline pH conditions. In comparison, Pediococcus pentosaceus UP-2 exhibited the highest ability to produce 15 AAs extracellularly, including aspartate, lysine, methionine, threonine, isoleucine, glutamate, proline, alanine, valine, leucine, tryptophan, tyrosine, serine, glycine, and cystine, followed by Pediococcus pentosaceus UL-2, Pediococcus acidilactici UB-6, and Pediococcus acidilactici UP-1 with 11 to 12 different AAs production detected extracellularly. Pediococcus pentosaceus UL-6 demonstrated the highest increment of proline production at 24 h of incubation. However, Pediococcus acidilactici UL-3 and Lactobacillus plantarum I-UL4 exhibited the greatest requirement for AA. The results of this study showed that different LAB possess different extracellular proteolytic activities and potentials as extracellular AA producers.


Assuntos
Aminoácidos/metabolismo , Microbiologia de Alimentos , Alimentos , Lactobacillus plantarum , Pediococcus , Humanos , Lactobacillus plantarum/isolamento & purificação , Lactobacillus plantarum/metabolismo , Malásia , Pediococcus/isolamento & purificação , Pediococcus/metabolismo
14.
Neuroradiology ; 61(6): 695-702, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30949745

RESUMO

PURPOSE: Previous studies have focused on global cerebral alterations observed in cirrhosis. However, little was known about the specific abnormalities of vision-related brain regions in cirrhotic patients. In this study, we sought to explore neurological alterations of vision-related regions by measuring brain resting-state network connectivity, based on the structural investigation in cirrhotic patients without clinical sign of hepatic encephalopathy (HE). METHODS: Structural and functional magnetic resonance image (MRI) data were collected from 20 hepatitis B virus (HBV)-related cirrhotic patients without clinical sign of HE and from 20 healthy controls (HC). Voxel-based morphometric (VBM) analysis and brain functional network analysis were performed to detect abnormalities in cerebral structure and function. RESULTS: Cirrhotic patients showed regions with the most significant gray matter reduction primarily in vision-related brain regions, including the bilateral lingual gyri, left putamen, right fusiform gyrus, and right calcarine gyrus, and other significant gray matter reductions were distributed in bilateral hippocampus. Based on structural investigation focused on vision-related regions, brain functional network analysis revealed decreased functional connectivity between brain functional networks within vision-related regions (primary visual network (PVN), higher visual network (HVN), visuospatial network (VSN)) in the patient group compared with HC group. CONCLUSION: These results indicate that structural and functional impairment were evident in the vision-related brain regions in cirrhotic patients without clinical sign of hepatic encephalopathy. The physiopathology and clinical relevance of these changes could not be ascertained from the present study, which provided a basis for further evolution of the disease.


Assuntos
Substância Cinzenta/diagnóstico por imagem , Encefalopatia Hepática/diagnóstico , Imagem por Ressonância Magnética/métodos , Córtex Visual/diagnóstico por imagem , Estudos de Casos e Controles , Feminino , Substância Cinzenta/patologia , Encefalopatia Hepática/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Córtex Visual/patologia
15.
Appl Opt ; 58(4): 1093-1100, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30874163

RESUMO

Being susceptible to the change of atmospheric conditions, the volume emission rate (VER) is very suitable to be used as a light source by passive remote sensing for measuring atmospheric wind and temperature. Thus, the VERs emitted from O2(0-1) and O(S1) of the nightglow at 80-120 km are studied in this paper. Based on the Naval Research Laboratory Mass Spectrometer Incoherent Scatter (NRLMSISE-00) model data and the ground-based airglow imaging interferometer (GBAII) instrument observation for a local time and place, simulated VER profiles represented by four layers are obtained for the nightglow of O2(0-1) and O(S1). The O2(0-1) nightglow model peak values at 94 km on 6 December 2013 and 8 November 2011 are 8111 photons·cm-3·s-1 and 8406 photons·cm-3·s-1, respectively; however, the O(S1) VER peak at a higher altitude of about 96 km on 18 December 2011 is only 338 photons·cm-3·s-1. The upper atmospheric VER values have been derived to transfer into the ground-based detected column intensities by our GBAII prototype. The calculated column integrated emission rates (IERs) of O2(0-1) for 0° and 45° zenith angles are 1.48×107 and 1.91×107 photons·cm-2·s-1, respectively; the calculated column IERs of O(S1) are 5.53×105 and 7.03×105 photons·cm-2·s-1, respectively. Correspondingly, the detected column IERs obtained by GBAII are 2.43×107 for O2(0-1) and 6.57×105 photons·cm-2·s-1 for O(S1).

16.
Environ Sci Pollut Res Int ; 26(13): 13235-13245, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30900120

RESUMO

Glutathione (GSH) is involved in not only plant developmental processes but also plant responses to abiotic stresses. A hydroponic experiment was performed to explore the protective roles of exogenous GSH in mitigating cadmium (Cd) stress in Brassica campestris L. seedlings by analyzing the morphological and physiological parameters. Results showed that Cd caused severe growth inhibition and Cd accumulation. However, application of GSH significantly mitigated toxic symptoms induced by Cd, including the improvement of the photosynthesis-, plant growth-, and root morphology-related parameters in seedlings under Cd stress. These responses were associated with a striking increase in activities of representative antioxidative enzymes and contents of corresponding non-enzymatic antioxidants. In vivo imaging of O2.- and H2O2, and the detection of lipid peroxidation further demonstrated that increased ability by GSH for Brassica campestris L. seedlings to endure Cd stress was consistent with a striking elevation of ratios of reduced to oxidized glutathione (GSH/GSSG) and ascorbic acid to dehydroascorbic acid (AsA/DHA). Additionally, GSH application increased Cd retained in roots, thus significantly decreased its translocation from root to shoot, ultimately decreased Cd accumulation in shoots. Taken together, our results proved evidence for GSH in ameliorating Cd toxicity via reducing Cd accumulation in shoots and increasing oxidation resistance. Accordingly, application of GSH could be a high-efficiency and promising strategy to decrease Cd concentration in edible parts of Brassica campestris L. in agricultural production.


Assuntos
Antioxidantes/farmacologia , Ácido Ascórbico/química , Brassica/crescimento & desenvolvimento , Cádmio/farmacologia , Glutationa/metabolismo , Peróxido de Hidrogênio/química , Plântula/metabolismo , Estresse Fisiológico/efeitos dos fármacos , Cádmio/química , Peroxidação de Lipídeos , Oxirredução
17.
Parasitol Res ; 118(5): 1653-1656, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30847612

RESUMO

Sparganosis is a parasitic infection caused by the metacestode stage of Spirometra mansoni and some other related diphyllobothriidean cestodes. Although various internal organs were involved in sparganum infection, pulmonary and pleural involvement is rarely reported. We herein report an uncommon form of sparganosis manifested by pleuritis and decreased peripheral blood eosinophils. Sparganum worms were found in the pleural effusion accidentally and confirmed by pathological diagnosis. After being treated with praziquantel for 10 days, the patient's symptoms, laboratory examinations, and imaging findings were improved gradually.


Assuntos
Eosinófilos/citologia , Derrame Pleural/parasitologia , Pleurisia/diagnóstico , Pleurisia/parasitologia , Praziquantel/uso terapêutico , Esparganose/diagnóstico , Esparganose/tratamento farmacológico , Plerocercoide/isolamento & purificação , Animais , China , Humanos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Esparganose/parasitologia
18.
J Agric Food Chem ; 67(13): 3554-3564, 2019 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-30860831

RESUMO

Cynomorium songaricum Rupr. is a valuable food and medicinal plant with functions, such as an increase in sexual function, mainly attributed to its complex secondary metabolites. However, the effect of internal microbes on metabolite production in C. songaricum is still largely unclear. In this study, the relationship between endophytes and differential secondary metabolites in C. songaricum from seven major producing regions of China were explored based on established methods of metabolomics and high-throughput sequencing. The results showed that there were 13 different marker metabolites, seven shared fungal OTUs, and numerous unshared OTUs among C. songaricum distributed at different locations in China and identified significant correlations between metabolites and endophytic fungi. Our study revealed that endophytic fungi may be one possible factor that can affect the plant secondary metabolite composition.


Assuntos
Cynomorium/microbiologia , Endófitos/isolamento & purificação , Fungos/isolamento & purificação , Micobioma , Plantas Medicinais/microbiologia , China , Cynomorium/química , Cynomorium/metabolismo , Clima Desértico , Endófitos/classificação , Endófitos/genética , Fungos/classificação , Fungos/genética , Plantas Medicinais/química , Plantas Medicinais/metabolismo
19.
Environ Int ; 126: 717-726, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30878867

RESUMO

Long term mining activities can cause significant metal pollution in the environment, thereby showing potential risk to the paddy field. Elucidating the interfacial processes of trace metals from contaminated paddy soil to rice within the rhizosphere can provide important information on metal biogeochemistry and food safety. The current study aims to explore the spatial distribution and molecular speciation of Cu from rhizosphere to rice plant in a mining-impacted paddy soil, and reveal the possible uptake mechanisms. X-ray absorption near edge structure (XANES) analysis indicated that Cu was primarily associated with iron oxide and sulfide in soil with a minor proportion of organic complexed species. In the rice samples, Cu showed much higher concentrations in the roots than the shoots, as most Cu was sequestered in the root surface and epidermis (primarily in the form of C/N ligands bound Cu species), rather than root xylem, as identified by micro X-ray fluorescence (µ-XRF) imaging coupling with µ-XANES. By contrast, in the root xylem, thiol-S bound Cu(I) complex was observed, representing the reduced product of Cu(II) by thiol-S ligands in rice root. The absorbed Cu was probably transported from the root to the aerial part as C/N ligand bound Cu complex such as Cu-histidine like species, which was observed in the root xylem. The large retention capacity and reduction of Cu(II) in rice root alleviated Cu toxicity to rice, which was beneficial for food safety (e.g., lower concentration of Cu in rice grains). These findings showed for the first time that the uptake mechanisms by rice from field contaminated sites, which shed light on Cu detoxification process and potential remediation strategies.

20.
J Clin Hypertens (Greenwich) ; 21(3): 412-420, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30737889

RESUMO

Acupuncture may be beneficial for patients with mild hypertension, but the evidence is not convincing. We aimed to examine the effect of acupuncture on blood pressure (BP) reduction in patients with mild hypertension. We conducted a multicenter, single-blind, sham-controlled, randomized trial in eleven hospitals in China. The trial included 428 patients with systolic blood pressure (SBP) from 140 to 159 mm Hg and/or with diastolic blood pressure (DBP) from 90 to 99 mm Hg. The patients were randomly assigned to receive 18 sessions of affected meridian acupuncture (n = 107) or non-affected meridian acupuncture (n = 107) or sham acupuncture (n = 107) during 6 weeks, or to stay in a waiting-list control (n = 107). All patients received 24-hour ambulatory blood pressure monitoring at weeks 6, 9, and 12. We included 415 participants in the intention-to-treat analysis. The two acupuncture groups were pooled in the analysis, since they had no difference in all outcomes. SBP decreased at week 6 in acupuncture group vs sham acupuncture vs waiting-list group (7.2 ± 11.0 mm Hg vs 4.1 ± 11.5 mm Hg vs 4.1 ± 13.2 mm Hg); acupuncture was not superior to sham acupuncture (mean difference 2.7 mm Hg, 95% CI 0.4 to 5.9, adjusted P = 0.103) or waiting-list control (2.9 mm Hg, 95% CI -0.2 to 6.0, adjusted P = 0.078). However, acupuncture was superior to sham acupuncture (3.3 mm Hg, 95% CI 0.2 to 6.3, adjusted P = 0.035) and waiting-list control (4.8 mm Hg, 95% CI 1.8 to 7.8, P < 0.001) at week 9. Acupuncture had a small effect size on the reduction of BP in patients with mild hypertension.

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