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1.
Math Biosci Eng ; 18(5): 5836-5864, 2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34517514

RESUMO

Since the meta-heuristic water cycle algorithm (WCA) was presented, it has been used extensively in scientific computation and engineering optimization. The aims of this study are to improve the exploration and exploitation capabilities of the WCA algorithm, accelerate its convergence speed, and enhance its calculation accuracy. In this paper, a novel complex-valued encoding WCA (CWCA) is proposed. The positions of rivers and streams are divided into two parts, that is, the real part and imaginary part, and modified formulas for the new positions of rivers and streams are proposed. To evaluate the performance of the CWCA, 12 benchmark functions and four engineering examples were considered. The experimental results indicated that the CWCA had higher precision and convergence speed than the real-valued WCA and other well-known meta-heuristic algorithms.

2.
Plant Physiol Biochem ; 167: 185-197, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34365289

RESUMO

During seedling photo-morphogenesis, cotyledon greening is a vital developmental process and a moment of responding to light stress. An increasing number of reports suggest the function of natural antioxidant protection of phenolic compounds in plant growth and development processes. Due to the antioxidant functions, flavonoids allow plants to respond to abiotic or biotic stresses. As one of the plants rich in secondary metabolites, Catharanthus roseus has drawn great academic interest due to its richness of diverse secondary metabolites with medicinal values. To assess the distribution and function of phenolic compounds during cotyledon greening, combined phenolic profiling and transcriptome were applied in C. roseus seedling through ultra-high performance liquid chromatography quadrupole time-of-flight mass spectrometer (UPLC-Q-TOF/MS) and high throughput RNA sequencing, respectively. Results herein showed that light-exposed greening cotyledon accumulated large amounts of C6C3C6-type flavonoids, suggesting the function in repressing reactive oxygen species (ROS) generation to improve light adaptation and seedling survival. Moreover, synergistic up-regulation of relevant genes involved in flavonoids pathway, including PAL, C4H, CHS, FLS, and F3'H, was monitored in response to light. Several crucial candidate transcription factors including bHLH, MYB, and B-box families were likely to function, and thereinto, CrHY5 (CRO_T122304) and CRO_T137938 revealed a prompt response to light, supposing to induce flavonoids accumulation by targeting CHS and FLS. Therefore, this study provided new insight into the potential regulation and underlying roles of flavonoids to improve light acclimation during cotyledon greening.


Assuntos
Catharanthus , Catharanthus/genética , Cotilédone , Flavonoides , Regulação da Expressão Gênica de Plantas , Plântula/genética , Transcriptoma
3.
Plant Physiol Biochem ; 167: 481-491, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34425393

RESUMO

Tissue loss of plants caused by herbivores is very common in nature. As the storage and first photosynthetic organ, the loss of cotyledon severely impacts dicot seedling establishment and the subsequent growth. However, it is still not clear how plants adjust their metabolic strategy in response to cotyledon loss. In this study, we employed ICP-OES, GC and LC-MS to examine the effects of cotyledon removal (RC1: remove one cotyledon, RC2: remove two cotyledon) on mineral element distribution and metabolite changes in a traditional Chinese herbal plant, Astragalus membranaceus. The results showed that cotyledon removal had a greater effect on shoot than root growth. Specifically, RC2 revealed a more serious impact on shoot growth than RC1. Microelement Mn and Na in shoot increased more in RC2 than RC1. Macroelement K and microelement B in root increased in RC2. The metabolite results in shoot showed that sugars related to galactose metabolism reduced while amino acids significantly increased in RC2. In root, sugars related to fructose and mannose metabolism decreased in both RC1 and RC2 while most flavonoids increased in RC2. It can be concluded that cotyledon removal triggered different metabolic strategies in both root and shoot. In shoot, more Mn was absorbed to improve the lowered photosynthetic efficiency. Meanwhile, increased Na may have promoted carbohydrate consumption and amino acid synthesis, thereby maintaining shoot growth. In root, K and B participation in cell division and expansion increased, as well as the delivery and metabolism of carbohydrates, to maintain root system growth.


Assuntos
Cotilédone , Plântula , Astragalus propinquus , Carboidratos , Minerais , Raízes de Plantas
4.
Nat Commun ; 12(1): 4502, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34301937

RESUMO

Cells in many tissues, such as bone, muscle, and placenta, fuse into syncytia to acquire new functions and transcriptional programs. While it is known that fused cells are specialized, it is unclear whether cell-fusion itself contributes to programmatic-changes that generate the new cellular state. Here, we address this by employing a fusogen-mediated, cell-fusion system to create syncytia from undifferentiated cells. RNA-Seq analysis reveals VSV-G-induced cell fusion precedes transcriptional changes. To gain mechanistic insights, we measure the plasma membrane surface area after cell-fusion and observe it diminishes through increases in endocytosis. Consequently, glucose transporters internalize, and cytoplasmic glucose and ATP transiently decrease. This reduced energetic state activates AMPK, which inhibits YAP1, causing transcriptional-reprogramming and cell-cycle arrest. Impairing either endocytosis or AMPK activity prevents YAP1 inhibition and cell-cycle arrest after fusion. Together, these data demonstrate plasma membrane diminishment upon cell-fusion causes transient nutrient stress that may promote transcriptional-reprogramming independent from extrinsic cues.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Membrana Celular/metabolismo , Núcleo Celular/metabolismo , Glicoproteínas de Membrana/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Genética/genética , Proteínas do Envelope Viral/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Transporte Biológico , Fusão Celular , Linhagem Celular , Linhagem Celular Tumoral , Células Cultivadas , Células Gigantes/metabolismo , Células HEK293 , Humanos , Glicoproteínas de Membrana/genética , Camundongos , RNA-Seq/métodos , Transdução de Sinais/genética , Fatores de Transcrição/genética , Proteínas do Envelope Viral/genética
5.
Cereb Cortex ; 2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34322696

RESUMO

Quality sleep is vital for physical and mental health. No matter whether sleep problems are a consequence of or contributory factor to mental disorders, people with psychosis often suffer from severe sleep disturbances. Previous research has shown that acute sleep deprivation (SD) can cause transient brain dysfunction and lead to various cognitive impairments in healthy individuals. However, the relationship between sleep disturbance and bistable perception remains unclear. Here, we investigated whether the bistable perception could be affected by SD and elucidated the functional brain changes accompanying SD effects on bistable perception using functional magnetic resonance imaging. We found that the 28-h SD resulted in slower perceptual transitions in healthy individuals. The reduced perceptual transition was accompanied by the decreased activations in rivalry-related frontoparietal areas, including the right superior parietal lobule, right frontal eye field, and right temporoparietal junction. We speculated that SD might disrupt the normal function of these regions crucial for bistable perception, which mediated the slower rivalry-related perceptual transitions in behavior. Our findings revealed the neural changes underlying the abnormal bistable perception following the SD. It also suggested that SD might offer a new window to understand the neural mechanisms underlying the bistable perception.

6.
Med (N Y) ; 2(5): 591-610.e10, 2021 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-33969332

RESUMO

Background: Pregnant women are at increased risk for severe outcomes from coronavirus disease 2019 (COVID-19), but the pathophysiology underlying this increased morbidity and its potential effect on the developing fetus is not well understood. Methods: We assessed placental histology, ACE2 expression, and viral and immune dynamics at the term placenta in pregnant women with and without respiratory severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Findings: The majority (13 of 15) of placentas analyzed had no detectable viral RNA. ACE2 was detected by immunohistochemistry in syncytiotrophoblast cells of the normal placenta during early pregnancy but was rarely seen in healthy placentas at full term, suggesting that low ACE2 expression may protect the term placenta from viral infection. Using immortalized cell lines and primary isolated placental cells, we found that cytotrophoblasts, the trophoblast stem cells and precursors to syncytiotrophoblasts, rather than syncytiotrophoblasts or Hofbauer cells, are most vulnerable to SARS-CoV-2 infection in vitro. To better understand potential immune mechanisms shielding placental cells from infection in vivo, we performed bulk and single-cell transcriptomics analyses and found that the maternal-fetal interface of SARS-CoV-2-infected women exhibited robust immune responses, including increased activation of natural killer (NK) and T cells, increased expression of interferon-related genes, as well as markers associated with pregnancy complications such as preeclampsia. Conclusions: SARS-CoV-2 infection in late pregnancy is associated with immune activation at the maternal-fetal interface even in the absence of detectable local viral invasion. Funding: NIH (T32GM007205, F30HD093350, K23MH118999, R01AI157488, U01DA040588) and Fast Grant funding support from Emergent Ventures at the Mercatus Center.

7.
Tree Physiol ; 41(10): 1953-1971, 2021 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-33791793

RESUMO

Polyploidy generally provides an advantage in phenotypic variation and growth vigor. However, the underlying mechanisms remain poorly understood. The tetraploid Liriodendron sino-americanum (Liriodendron × sinoamericanum P.C Yieh ex C.B. Shang & Zhang R.Wang) exhibits altered morphology compared with its diploid counterpart, including larger, thicker and deeper green leaves, bigger stomata, thicker stems and increased tree height. Such characteristics can be useful in ornamental and industrial applications. To elucidate the molecular mechanisms behind this variation, we performed a comparative transcriptome and proteome analysis. Our transcriptome data indicated that some photosynthesis genes and pathways were differentially altered and enriched in tetraploid L. sino-americanum, mainly related to F-type ATPase, the cytochrome b6/f complex, photosynthetic electron transport, the light harvesting chlorophyll protein complexes, and photosystem I and II. Most of the differentially expressed proteins we could identify are also involved in photosynthesis. Our physiological results showed that tetraploids have an enhanced photosynthetic capacity, concomitant with great levels of sugar and starch in leaves. This suggests that tetraploid L. sino-americanum might experience comprehensive transcriptome reprogramming of genes related to photosynthesis. This study has especially emphasized molecular changes involved in photosynthesis that accompany polyploidy, and provides a possible explanation for the altered phenotype of polyploidy plants in comparison with their diploid form.

8.
Open Life Sci ; 16(1): 287-296, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33817320

RESUMO

Taxus species have attracted much attention for their potency in cancer treatment. However, investigating the bioactivities of Taxus species is a complex task, due to their diversity, slow growth, and endangered state. The most important Taxus species in China are Taxus chinensis (T. chinensis), Taxus cuspidata (T. cuspidata), and Taxus × media (T. media), which mainly grow in the northeastern region. This article probes deep into the differences among the leaves of T. chinensis, T. cuspidata, and T. media, with the aid of gas chromatography-mass spectrometry (GC-MS). Through GC-MS, 162 compounds were detected in the samples and found to contain 35 bioactive metabolites. On this basis, 20 metabolites with significant bioactivities (antibiotic, antioxidant, anticancer, and antiaging effects) were identified via unsupervised learning of principal component analysis and supervised learning of partial least squares-discriminant analysis. The results show that T. media has the most prominent antibiotic, antioxidant, and anticancer effects, while T. cuspidata has the most diverse and abundant metabolites that slow down aging.

9.
BMC Plant Biol ; 21(1): 154, 2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33771114

RESUMO

BACKGROUND: Mechanical damage is an unavoidable threat to the growth and survival of plants. Although a wound to senescing (lower) leaves improves plant vitality, a wound to younger (upper) leaves often causes damage to or death of the whole plant. Source-sink models are often used to explain how plants respond to biotic or abiotic stresses. In this study, a source-sink model was used to explain the difference in the metabolic mechanism of mechanical damage to young and senescing leaves of Catharanthus roseus. RESULTS: In our study, GC-MS and LC-QTOF-MS metabolomics techniques were used to explore the differences in source-sink allocation and metabolic regulation in different organs of Catharanthus roseus after mechanical damage to the upper/lower leaves (WUL/WLL). Compared with that of the control group, the energy supplies of the WUL and WLL groups were increased and delivered to the secondary metabolic pathway through the TCA cycle. The two treatment groups adopted different secondary metabolic response strategies. The WLL group increased the input to the defense response after damage by increasing the accumulation of phenolics. A source-sink model was applied to the defensive responses to local (damaged leaves) and systemic (whole plant) damage. In the WUL group, the number of sinks increased due to damage to young leaves, and the tolerance response was emphasized. CONCLUSION: The accumulation of primary and secondary metabolites was significantly different between the two mechanical damage treatments. Catharanthus roseus uses different trade-offs between tolerance (repair) and defense to respond to mechanical damage. Repairing damage and chemical defenses are thought to be more energetically expensive than growth development, confirming the trade-offs and allocation of resources seen in this source-sink model.


Assuntos
Catharanthus/metabolismo , Folhas de Planta/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Redes e Vias Metabólicas , Metabolômica , Modelos Biológicos , Doenças das Plantas
10.
medRxiv ; 2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-33532791

RESUMO

Pregnant women appear to be at increased risk for severe outcomes associated with COVID-19, but the pathophysiology underlying this increased morbidity and its potential impact on the developing fetus is not well understood. In this study of pregnant women with and without COVID-19, we assessed viral and immune dynamics at the placenta during maternal SARS-CoV-2 infection. Amongst uninfected women, ACE2 was detected by immunohistochemistry in syncytiotrophoblast cells of the normal placenta during early pregnancy but was rarely seen in healthy placentas at full term. Term placentas from women infected with SARS-CoV-2, however, displayed a significant increase in ACE2 levels. Using immortalized cell lines and primary isolated placental cells, we determined the vulnerability of various placental cell types to direct infection by SARS-CoV-2 in vitro . Yet, despite the susceptibility of placental cells to SARS-CoV-2 infection, viral RNA was detected in the placentas of only a subset (∼13%) of women in this cohort. Through single cell transcriptomic analyses, we found that the maternal-fetal interface of SARS-CoV-2-infected women exhibited markers associated with pregnancy complications, such as preeclampsia, and robust immune responses, including increased activation of placental NK and T cells and increased expression of interferon-related genes. Overall, this study suggests that SARS-CoV-2 is associated with immune activation at the maternal-fetal interface even in the absence of detectable local viral invasion. While this likely represents a protective mechanism shielding the placenta from infection, inflammatory changes in the placenta may also contribute to poor pregnancy outcomes and thus warrant further investigation.

11.
Gland Surg ; 10(1): 175-185, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33633974

RESUMO

Background: Breast cancer is currently the most common female malignancy in China. However, the clinical features and overall prognosis of young women diagnosed with this malignancy remain unclear. This study aimed to describe the clinicopathological characteristics of young patients (≤34 years of age) with breast cancer and explore the current treatment approaches used in China. Methods: This was a hospital-based, multicenter, retrospective study of women with breast cancer across seven Chinese hospitals from 1999 to 2008. A total of 295 young (≤34 years of age) patients (research group) and 2,119 women aged 35 to 49 years (control group) were included in the study. Patient epidemiology, pre-operative examinations, clinical pathology, and treatment were analyzed. Results: The percentage of young patients with breast cancer in the study group was 7.01%. These young women had a lower body mass index (BMI), a higher level of education, a lower number of previous births, and a lower history of breastfeeding than the control group (P<0.05). Increasingly, pre-operative use of ultrasound and magnetic resonance imaging are being used to diagnose breast cancer in young women in China. In young women with breast cancer, breast cancer not otherwise specified (NOS) was the primary pathology. The carcinoma in young women was more prone to lymph node metastasis, showed less progesterone receptor (PR) expression, and was more advanced than observed in the control group (P<0.05). We found that the number of young breast cancer patients undergoing breast-conserving surgery in China is increasing. Conclusions: Young breast cancer patients display unique clinicopathological features, including tumors of a higher grade than those aged 35 years or older. As breast cancer is more aggressive in younger women, prevention and early diagnosis are critical, and new policies should be developed in line with these findings.

12.
Cryobiology ; 99: 46-54, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33524338

RESUMO

Antioxidant defense is essential for animals to cope with homeostasis disruption during hibernation. The present study aimed to investigate the antioxidant defense response of juvenile soft-shelled turtle Pelodiscus sinensis during hibernation and following arousal. Turtle brain, liver, and kidney samples were collected at pre-hibernation (17 °C mud temperature; MT), during hibernation (5.8 °C MT) and after arousal (20.1 °C MT) in the field. Transcript levels of NF-E2-related factor 2 (Nrf2) decreased significantly during hibernation and recovered after arousal in all tissues. Cerebral and nephric copper-zinc superoxide dismutase (Cu/Zn SOD), catalase (CAT), glutathione peroxidase 3 (GPx3) and nephric GPx4 mRNA showed similar changing patterns as Nrf2. Cerebral Mn SOD, GPx1 and nephric GPx1 up-regulated after arousal. Hepatic Cu/Zn SOD, GPx1 and GPx3 mRNA kept stable, except hepatic GPx4 increased during hibernation. Hepatic Mn SOD and CAT increased after arousal. In the GSH system, mRNA levels of glutathione synthetases (GSs) kept stable during hibernation and up-regulated after arousal in most tissues except nephric GS2 mRNA remained unchanged. Gene expressions of glutathione reductase (GR) exhibited a tissue specific changing pattern, while those of glutathione-S-Transferase (GST) shared a similar pattern among tissues: remained stable or down-regulated during hibernation then recovered in arousal. In contrast to these diverse responses in gene expressions, most of the antioxidant enzyme activities maintained high and stable. Overall, no preparation for oxidative stress (POS) strategy was found in enzymatic antioxidant system in P. sinensis juveniles during hibernation, the Chinese soft-shelled turtles were able to stay safe from potential oxidative stress during hibernation by maintaining high level activities/concentrations of the antioxidant enzymes/antioxidants.


Assuntos
Hibernação , Tartarugas , Animais , Antioxidantes , Nível de Alerta , Catalase/genética , Catalase/metabolismo , China , Criopreservação/métodos , Estresse Oxidativo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Tartarugas/genética
13.
Nat Prod Res ; 35(3): 499-502, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31282217

RESUMO

Suaeda glauca and Puccinellia tenuiflora are two important saline-alkali tolerant plants that can improve the soil properties. For exploring the different tolerance mechanisms between them, GC-MS-based metabolomics was used to comprehensively evaluate the primary metabolites differences, a total of 51 different metabolites were present in different quantities. The identified compounds were mainly 11 sugars, 7 amino acids, 5 alcohols and 18 organic acids; they play an important role in responding to the saline-alkali stress and distinguish between S. glauca and P. tenuiflora. All identified metabolites classes showed similar trend to largely accumulate in P. tenuiflora roots and S. glauca shoots, this reveals that the two plants used different physiological strategies to cope with saline-alkali stress.


Assuntos
Chenopodiaceae/metabolismo , Poaceae/metabolismo , Plantas Tolerantes a Sal/metabolismo , Solo/química , Álcoois/metabolismo , Aminoácidos/metabolismo , Chenopodiaceae/fisiologia , Cromatografia Gasosa-Espectrometria de Massas , Metabolômica , Raízes de Plantas/metabolismo , Poaceae/fisiologia , Plantas Tolerantes a Sal/fisiologia , Estresse Fisiológico , Açúcares/metabolismo
14.
J Immunol ; 205(11): 3083-3094, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33139490

RESUMO

Vertical transmission of the Zika virus (ZIKV) causes severe fetal defects, but the exact pathogenic mechanism is unclear. We identified up to a 10,480-fold higher expression of viral attachment factors AXL, GAS6, and PROS1 and a 3880-fold increase in ZIKV infectiousness/propagation in human term decidual stromal cells versus trophoblasts. Moreover, levels of viral attachment factors and ZIKV are significantly increased, whereas expression of innate immune response genes are significantly decreased, in human first trimester versus term decidual cells. ZIKV-infected decidual cell supernatants increased cytotrophoblasts infection up to 252-fold compared with directly infected cytotrophoblasts. Tizoxanide treatment efficiently inhibited Zika infection in both maternal and fetal cells. We conclude that ZIKV permissiveness, as well as innate immune responsiveness of human decidual cells, are gestational age dependent, and decidual cells augment ZIKV infection of primary human cytotrophoblast cultures, which are otherwise ZIKV resistant. Human decidual cells may act as reservoirs for trimester-dependent placental transmission of ZIKV, accounting for the higher Zika infection susceptibility and more severe fetal sequelae observed in early versus late pregnancy. Moreover, tizoxanide is a promising agent in preventing perinatal Zika transmission as well as other RNA viruses such as coronavirus.


Assuntos
Decídua , Idade Gestacional , Imunidade Inata , Transmissão Vertical de Doenças Infecciosas , Complicações Infecciosas na Gravidez , Infecção por Zika virus , Zika virus/imunologia , Animais , Chlorocebus aethiops , Decídua/imunologia , Decídua/patologia , Decídua/virologia , Feminino , Humanos , Gravidez , Complicações Infecciosas na Gravidez/imunologia , Complicações Infecciosas na Gravidez/patologia , Trofoblastos , Células Vero , Infecção por Zika virus/imunologia , Infecção por Zika virus/patologia , Infecção por Zika virus/transmissão
15.
J Reprod Immunol ; 142: 103214, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33152658

RESUMO

Alterations in the number and protein/gene expression of Hofbauer cells (HBCs) may play a role in microbial-driven/cytokine-mediated placental inflammation, and in subsequent pregnancy complications such as villitis, histologic chorioamnionitis, and the fetal inflammatory response syndrome. Pyroptosis is an inflammatory form of cell death mediated by the inflammasome, a multi-protein complex which drives the processing and secretion of interleukin 1 beta (IL-1ß). Pyroptosis can be triggered by bacterial lipopolysaccharide (LPS) and adenosine triphosphate (ATP) in non-placental macrophages through activation of the NLRP3 inflammasome. However, the role of inflammasome activation and pyroptosis in HBC pathophysiology remains unclear. HBCs isolated from human term placentas were treated with or without LPS or ATP, alone or in combination. Treatment of HBCs with both LPS and ATP induced the rapid secretion of high levels of IL-1ß and at the same time, cell death associated with nuclear condensation and cellular swelling. HBC treatment with both LPS and ATP induced caspase-1 activation, gasdermin D (GSDMD) cleavage, which mediates pyroptosis, and IL-1ß processing. Caspase-1 activation, GSDMD cleavage, IL-1ß processing, and IL-1ß secretion were all significantly reduced following NLRP3 knockdown; inhibition of caspase-1; and inhibition of P2X7, the receptor that mediates K+ efflux. Together, our data indicate that LPS and ATP treatment stimulated NLRP3 inflammasome activation and pyroptosis in HBCs leading to the rapid release of IL-1ß. Since the localization of HBCs confers a unique ability to influence microbial-associated placental and fetal inflammation, these studies suggest a key role for the inflammasome and pyroptosis in mediating HBC driven inflammation.

16.
J Pak Med Assoc ; 70 [Special Issue](9): 64-70, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33177730

RESUMO

OBJECTIVE: The study aimed to explore the method of constructing the upper respiratory tract model of patients with obstructive sleep apnoea hypopnoea syndrome (OSAHS) and its application in the detection of the changes of flow field characteristics of the upper respiratory tract before and after surgical treatment. METHODS: A 34-year-old male OSAHS patient was taken as the study subject. The improved Han-uvulopalato pharyngoplasty was adopted for treatment. A 3D model of the patient's upper respiratory tract was constructed based on CT scan results before and after surgery. The characteristics of upper respiratory tract flow field were analyzed based on computational hydrodynamics under unsteady respiratory conditions. RESULTS: A 3D model of the patient's upper respiratory tract was successfully constructed. And after the comparison, it was found that the patients' respiratory tract stenosis was significantly improved after surgical treatment. During inhalation and exhalation, the high pressure areas of the patient were located in the nasal vestibule and oropharynx respectively. Surgical treatment can significantly reduce maximum stress. The total pressure of the upper respiratory tract decreased by 16.9%, and the pressure of the nasopharynx and oropharynx decreased by 70.1% and 38.4%, respectively. CONCLUSIONS: For the oropharyngeal area, the surgical treatment had obvious efficacy for inspiration, and during expiration, it had no efficacy but with adverse symptoms being increased.


Assuntos
Hidrodinâmica , Apneia Obstrutiva do Sono , Adulto , Humanos , Masculino , Nasofaringe/diagnóstico por imagem , Nasofaringe/cirurgia , Nariz , Faringe/diagnóstico por imagem , Faringe/cirurgia , Apneia Obstrutiva do Sono/cirurgia
17.
Environ Sci Pollut Res Int ; 27(27): 33773-33791, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32533496

RESUMO

The CO2 injection capacity directly affects the CO2 storage efficiency. Injection temperature and formation sloping degree affect the CO2 injection capacity. Based on the actual geological conditions of the Shiqianfeng Formation in the Ordos Basin of China, a three-dimensional (3D) simulation model was established to evaluate pressure, temperature, CO2 spatial distribution, and injection amount. A total of 17 simulation schemes were carried out using the TOUGH2-ECO2N fluid property module. The results showed that the injection temperature had a significant impact on the CO2 injection capacity in the different sloping degree formations. Increasing the injection temperature resulted in increased formation pressure, CO2 gas phase, dissolved phase, and total injection amount, while decreasing the CO2 concentration, and the formation pressure changed obviously with the formation sloping degree. The larger the formation sloping degree was, the less the CO2 injection amount. Higher injection temperature and smaller sloping degree formation were more favorable for CO2 injection, and the CO2 injection capacity was stronger, signaling that it should be selected to store CO2 in the future.


Assuntos
Dióxido de Carbono/análise , Geologia , China , Temperatura
18.
J Pharm Biomed Anal ; 188: 113368, 2020 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-32544758

RESUMO

Panax ginseng is one of the most valuable medicinal plants in the world, and wild-forest (WG) and artificial-forest (AG) ginseng are very popular in the ginseng market, with ginsenosides constituting a majority of the bioactives. Research on the biochemical and physiological patterns of metabolic accumulation in different tissues of ginseng cultivated under various conditions is relatively scarce. We profiled metabolites using GC/MS and LC/MS to explore the bioactive component changes and interrelationships that occur in 7 tissues of WG and AG. In total, 149 primary metabolites and 46 secondary compounds were found in aboveground and belowground tissues. Metabolite changes associated with primary and secondary biochemistry were observed, and the levels of ginsenoside F2 and other compounds showed a significant correlation by statistical analysis in ginseng under both cultivation methods, as observed for secondary compounds and C and N metabolites. In addition, the number of secondary components was higher in the aboveground parts than in the belowground parts, showing a different pattern, and the same accumulation pattern of compounds involved in C and N metabolism was observed in individual plant tissues, but the high rate of photosynthesis and energy metabolism in WG provided energy for the biosynthesis of secondary compounds. Furthermore, artificial neural network models explained the variation in the secondary compounds very well via the combination of several different metabolites from WG and AG. Finally, C and N metabolism plays a key role in secondary compound biosynthesis in specific tissues and cultivation conditions and highlights large-scale metabolite patterns in WG and AG.


Assuntos
Ginsenosídeos , Panax , Plantas Medicinais , Cromatografia Líquida , Cromatografia Gasosa-Espectrometria de Massas , Ginsenosídeos/análise , Espectrometria de Massas
19.
Nature ; 581(7806): 89-93, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32376953

RESUMO

Small interfering RNAs (siRNAs) are essential for proper development and immunity in eukaryotes1. Plants produce siRNAs with lengths of 21, 22 or 24 nucleotides. The 21- and 24-nucleotide species mediate cleavage of messenger RNAs and DNA methylation2,3, respectively, but the biological functions of the 22-nucleotide siRNAs remain unknown. Here we report the identification and characterization of a group of endogenous 22-nucleotide siRNAs that are generated by the DICER-LIKE 2 (DCL2) protein in plants. When cytoplasmic RNA decay and DCL4 are deficient, the resulting massive accumulation of 22-nucleotide siRNAs causes pleiotropic growth disorders, including severe dwarfism, meristem defects and pigmentation. Notably, two genes that encode nitrate reductases-NIA1 and NIA2-produce nearly half of the 22-nucleotide siRNAs. Production of 22-nucleotide siRNAs triggers the amplification of gene silencing and induces translational repression both gene specifically and globally. Moreover, these 22-nucleotide siRNAs preferentially accumulate upon environmental stress, especially those siRNAs derived from NIA1/2, which act to restrain translation, inhibit plant growth and enhance stress responses. Thus, our research uncovers the unique properties of 22-nucleotide siRNAs, and reveals their importance in plant adaptation to environmental stresses.


Assuntos
Aclimatação/genética , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Biossíntese de Proteínas/genética , RNA de Plantas/genética , RNA Interferente Pequeno/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas Argonauta/metabolismo , Proteínas de Ciclo Celular , Inativação Gênica , Mutação , Nitrato Redutase/genética , Doenças das Plantas/genética , Estabilidade de RNA , RNA Mensageiro/genética , RNA Interferente Pequeno/biossíntese , Ribonuclease III/metabolismo
20.
Biomolecules ; 10(4)2020 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-32225015

RESUMO

: Ultraviolet-B (UV-B) radiation (280-320 nm) may induce photobiological stress in plants, activate the plant defense system, and induce changes of metabolites. In our previous work, we found that between the two Astragalus varieties prescribed by the Chinese Pharmacopoeia, Astragalus mongholicus has better tolerance to UV-B. Thus, it is necessary to study the metabolic strategy of Astragalus under UV-B radiation further. In the present study, we used untargeted gas chromatography-mass spectrometry (GC-MS) and targeted liquid chromatography-mass spectrometry (LC-MS techniques) to investigate the profiles of primary and secondary metabolic. The profiles revealed the metabolic response of Astragalus to UV-B radiation. We then used real-time polymerase chain reaction (RT-PCR) to obtain the transcription level of relevant genes under UV-B radiation (UV-B supplemented in the field, λmax = 313 nm, 30 W, lamp-leaf distance = 60 cm, 40 min·day-1), which annotated the responsive mechanism of phenolic metabolism in roots. Our results indicated that supplemental UV-B radiation induced a stronger shift from carbon assimilation to carbon accumulation. The flux through the phenylpropanoids pathway increased due to the mobilization of carbon reserves. The response of metabolism was observed to be significantly tissue-specific upon the UV-B radiation treatment. Among phenolic compounds, C6C1 carbon compounds (phenolic acids in leaves) and C6C3C6 carbon compounds (flavones in leaves and isoflavones in roots) increased at the expense of C6C3 carbon compounds. Verification experiments show that the response of phenolics in roots to UV-B is activated by upregulation of relevant genes rather than phenylalanine. Overall, this study reveals the tissues-specific alteration and mechanism of primary and secondary metabolic strategy in response to UV-B radiation.


Assuntos
Astragalus propinquus/metabolismo , Astragalus propinquus/efeitos da radiação , Fenóis/metabolismo , Astragalus propinquus/genética , Cromatografia Líquida , Flavonoides/genética , Flavonoides/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Regulação da Expressão Gênica de Plantas , Hidroxibenzoatos/metabolismo , Espectrometria de Massas , Folhas de Planta/metabolismo , Folhas de Planta/efeitos da radiação , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Plantas Medicinais , Metabolismo Secundário , Plântula/genética , Plântula/metabolismo , Plântula/efeitos da radiação , Raios Ultravioleta
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