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1.
New Phytol ; 2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34761409

RESUMO

MicroRNAs (miRNAs) are a class of 21-24 nucleotides (nt) noncoding small RNAs ubiquitously distributed across the plant kingdom. miR482/2118, one of the conserved miRNA superfamilies originating from gymnosperms, has divergent main functions in core-angiosperms. It mainly regulates NUCLEOTIDE BINDING SITE-LEUCINE-RICH REPEAT (NBS-LRR) genes in eudicots, functioning as an essential component in plant disease resistance; in contrast, it predominantly targets numerous long noncoding RNAs (lncRNAs) in monocot grasses, which are vital for plant reproduction. Usually, miR482/2118 is 22-nt in length, which can trigger the production of phased small interfering RNAs (phasiRNAs) after directed cleavage. PhasiRNAs instigated from target genes of miR482/2118 enhance their roles in corresponding biological processes by cis-regulation on cognate genes and expands their function to other pathways via trans activity on different genes. This review summarizes the origin, biogenesis, conservation, and evolutionary characteristics of the miR482/2118 superfamily and delineates its diverse functions in disease resistance, plant development, stress responses, etc.

2.
Front Nutr ; 8: 726108, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34722607

RESUMO

Fatty liver and intestinal barrier damage were widespread in most farmed fish, which severely restrict the development of aquaculture. Therefore, there was an urgent need to develop green feed additives to maintain host liver and intestinal health. In this study, a probiotic pili-like protein, Amuc_1100 (AM protein), was anchored to the surface of Lactococcus lactis ZHY1, and the effects of the recombinant bacteria AM-ZHY1 on liver fat accumulation and intestinal health were evaluated. Zebrafish were fed a basal diet, high-fat diet, and high-fat diet with AM-ZHY1 (108 cfu/g) or control bacteria ZHY1 for 4 weeks. Treatment with AM-ZHY1 significantly reduced hepatic steatosis in zebrafish. Quantitative PCR (qPCR) detection showed that the expression of the lipogenesis [peroxisome-proliferator-activated receptors (PPARγ), sterol regulatory element-binding proteins-1c (SREBP-1c), fatty acid synthase (FAS), and acetyl-CoA carboxylase 1 (ACC1)] and lipid transport genes (CD36 and FABP6) in the liver were significantly downregulated (p < 0.05), indicating that AM-ZHY1 could reduce liver fat accumulation by inhibiting lipid synthesis and absorption. Moreover, supplementing AM-ZHY1 to a high-fat diet could significantly reduce serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels, indicating that liver injury caused by high-fat diets was improved. The expression of tumor necrosis factor (TNF)-a and interleukin (IL)-6 in the liver decreased significantly (p < 0.05), while IL-1ß and IL-10 did not change significantly in the AM-ZHY1 group. Compared to the high-fat diet-fed group, the AM-ZHY1 group, but not the ZHY1 group, significantly increased the expression of intestinal tight junction (TJ) proteins (TJP1a, claudina, claudin7, claudin7b, claudin11a, claudin12, and claudin15a; p < 0.05). Compared to the high-fat diet group, the Proteobacteria and Fusobacteria were significantly reduced and increased in the AM-ZHY1 group, respectively. In conclusion, the recombinant bacteria AM-ZHY1 has the capacity to maintain intestinal health by protecting intestinal integrity and improving intestinal flora structure and improving fatty liver disease by inhibiting lipid synthesis and absorption. This study will lay a foundation for the application of AM protein in improving abnormal fat deposition and restoring the intestinal barrier in fish.

3.
BMC Med Imaging ; 21(1): 173, 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34800982

RESUMO

BACKGROUND: This study investigates the segmental myocardial strain of the early phase of intramyocardial hemorrhage (IMH) caused by reperfused myocardial infarction (MI) in rats by low-dose dobutamine (LDD) cardiovascular magnetic resonance (CMR) feature-tracking. METHODS: Nine sham rats and nine rats with 60-min myocardial ischemia followed by 48-h reperfusion were investigated using CMR, including T2*-mapping sequence and fast imaging with steady-state precession (FISP)-cine sequence. Another FISP-cine sequence was acquired after 2 min of dobutamine injection; the MI, IMH, and Non-MI (NMI) areas were identified. The values of peak radial strains (PRS) and peak circumferential strains (PCS) of the MI, IMH and NMI segments were acquired. The efficiency of PRS and PCS (EPRS and EPCS, respectively) were calculated on the basis of the time of every single heartbeat. RESULTS: The PRS, PCS, EPRS, and EPCS of the sham group increased after LDD injection. However, the PRS, PCS, EPRS, and EPCS of the IMH segment did not increase. Moreover, the PRS and PCS of the MI and NMI segments did not increase, but the EPRS and EPCS of these segments increased. The PRS, PCS, EPRS, and EPCS of the IMH segment were lower than those of the MI and NMI segments before and after LDD injection, but without a significant difference between MI segment and NMI segment before and after LDD injection. CONCLUSIONS: LDD could help assess dysfunctions in segments with IMH, especially using the efficiency of strain. IMH was a crucial factor that decreased segmental movement and reserved function.

5.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 37(2): 147-153, 2021 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-34672152

RESUMO

Objective: To verify that the cardiopulmonary exercise testing (CPET) performed by clinical subjects is the maximum extreme exercise, we designed The Max test(Max)during clinical CPET. We used Max to verify the accuracy of the quantitative CPET evaluation result, and whether it is feasible and safe to use the specific value of a certain index as the standard for stopping CPET. Methods: Two hundred and sixteen cases from Fuwai Hospital were selected during June 2017 to January 2019,including 41 healthy person(control group) and 175with cardiovascular diseases(patient group),The patients had a CPET peak RER ≤ 1.10, or the peak heart rate and peak blood pressure were basically non-responsive.The Max was first attempted in 60 subjects,and this study is further expanded . When the CPET ended, they had a 5-minute break, then the Max, during which, they cycled with a velocity of ≥ 60 r/min, at a constant intensity equivalent to to 130% of peak work,until exhausted.The difference and percentage difference between the peak heart rate and the peak oxygen uptake were calculated. ①If the percentage difference of heart rate and oxygen uptake are all less than -10%,then the Max is defined as failure,otherwise it is succesful. 2 If the percentage difference is between -10%~10%, then the Max is successful, which proved that the CPET is precise.③If the difference is ≥10%, the Max is successful, which proves that the CPET is non-extreme exercise. Results: Patient group's Peak VO2(L/min,ml/(min·kg)),anaerobic threshold (L/min,ml/(min·kg),%pred),Peak VO2/HR(ml/beat, % pred),Peak RER,Peak SBP,Peak WR,peak heart rate,OUEP (ratio,%pred) were lower than those of the control group(P<0.05).The VE/ VCO2 Slope (ratio,%pred)and Lowest VE/ VCO2(ratio,%pred) were higher in the patient group than in the control group (P<0.05).No adverse events occurred during the CPET and Max in all cases. Among the 216 cases,Max was successful in 198 cases(91.7%).CPET was proved to be maximum extreme exercise for 182 cases,non-maximum extreme exercise for 16 cases,and failed in 18 cases(8.3%).Conclusion: For CPET with a low peak RER and a maximum challenge,the Max can confirm the accuracy of the objective quantitative assessment of CPET. Max is safe and feasible,and that deserved further research and clinical application.


Assuntos
Teste de Esforço , Insuficiência Cardíaca , Limiar Anaeróbio , Exercício Físico , Humanos , Consumo de Oxigênio
6.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 37(2): 162-168, 2021 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-34672154

RESUMO

Objective: The cardiopulmonary function of patients with chronic heart failure (CHF) was severely limited, but the holistic integrative exercise pathophysiology is still unclear. Methods: After signed the consent form, Eighty three patients with severe CHF from October 2016 to October 2017 in Fuwai Hospital were performed Ramp incremental loading program CardioPulmonary Exercise Testing (CPET), and 12 normal subjects served as control. CPET were performed according to standard of Harbor-UCLA MC and the circulatory, respiratory and metabolic parameters during CPET were measured and analyzed. Results: Peak oxygen uptake (Peak VO2) in CHF (14.33±2.69) ml/(min·kg), (44.25±14.74)%pred was significantly lower than control ((29.42±5.46) ml/(min·kg), (83.88±6.28)%pred). Other core parameters of CPET such as anaerobic threshold (AT), peak oxygen pulse, oxygen uptake efficiency platform (OUEP), the lowest of carbon dioxide output ventilation ratio (Lowest VE/VCO2), and carbon dioxide output ventilation slope (VE/VCO2 Slope) in CHF were significantly different with the control group(P<0.01). The core parameters of lung function, such as forced expiratory volume in the first second (FEV1), forced vital capacity (FVC), FEV1/FVC, and carbon monoxide diffusion (DLCO) were significantly decreased (P<0.01). Systolic blood pressure during all stages of CPET in CHF was significantly lower than control group (P<0.05); Heart rate at AT, peak and recovery stages were significantly lower than control (P<0.01). Minute ventilation, tidal volume and respiratory frequency at rest, warm-up were significantly higher than control (P<0.05). Tidal volume at recovery was significantly higher than control (P<0.05). VO2 at AT, peak and recovery stages in CHF were significantly higher than control (P<0.01). Oxygen pulse at AT and peak were significantly higher than control (P<0.01). Pulse oxygen saturation during all stages of CPET in CHF were significantly lower than control (P<0.01). Conclusion: The decreased holistic functional capacity of cardiogenic CHF dominantly due to circulatory limitation, and secondly due to respiratory and metabolic limitation.


Assuntos
Exercício Físico , Insuficiência Cardíaca , Limiar Anaeróbio , Teste de Esforço , Humanos , Consumo de Oxigênio
7.
Front Physiol ; 12: 701151, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34675813

RESUMO

Background: Oxidative stress (OS) plays an important role in the progression of many aging-related diseases. Exercises can delay this kind of progress, but aerobic exercise is the most commonly used type of training among older adults; therefore, its influence needs to be further verified. Methods: A literature search was conducted in eight electronic databases, including Cochrane, EMBASE, PubMed, Web of Science, China National Knowledge Infrastructure (CNKI), China Science and Technology Journal Database (VIP), Wanfang Date, and SinoMed from their inception to April 2020. Methodological quality was assessed using Cochrane RoB tool v2.0 for individual studies, and RevMan 5.3 software was used to perform the meta-analysis. Results: The meta-analysis included 20 studies, involving 1,170 older adults. The results showed that regular aerobic exercise could reduce blood oxidant markers, including malondialdehyde (MDA; SMD=-1.80, 95% CI -2.46 to -1.14, p<0.001) and lipid peroxide (LPO; SMD=-1.12, 95% CI -2.03 to -0.22, p=0.02), and increase the levels of antioxidant factors, such as nitric oxide (NO; SMD=0.89, 95% CI 0.37-1.41, p<0.001), superoxide dismutase (SOD; SMD=0.63, 95% CI 0.25-1.01, p=0.001), and total antioxidant capacity (TAC; SMD=1.22, 95% CI 0.45-1.98, p=0.002), with clear statistical significance. It may also improve the levels of other OS markers, such as 8-OHdG, 8-isoPGF2, VE, and reduced glutathione/oxidized glutathione (GSH/GSSG). Conclusion: Regular aerobic exercise may have a positive effect on the OS levels of older adults by reducing some oxidant markers and increasing antioxidant marker levels.

8.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 37(2): 113-119, 2021 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-34672147

RESUMO

Objective: To observe the effect of healthy volunteers different work rate increasing rate cardiopulmonary exercise test (CPET) on the peak exercise core indicators and the changes of respiratory exchange rate (RER) during exercise, to explore the effect of different work rate increasing rate on CPET peak exercise related indicators. Methods: Twelve healthy volunteers were randomly assigned to a moderate (30 W/min), a relatively low (10 W/min) and relatively high (60 W/min) three different work rate increasing rate CPET on different working days in a week. The main peak exercise core indicators of CPET data: VO2, VCO2, work rate (WR), breathe frequency(Bf), tidal volume (VT), ventilation (VE), heart rate (HR), blood pressure (BP), Oxygen pulse(O2P), exercise time and RER for each period of CPET were analyzed using standard methods. The ANOVA test and paired two-two comparison was performed on the difference of each index in the three groups of different work rate increasing rate. Results: Compared with the moderate work rate group, the peak work rate of the lower and higher work rate groups were relatively lower and higher, respectively ((162.04±41.59) W/min vs (132.92±34.55) W/min vs (197.42±46.14) W/min, P<0.01); exercise time was significantly prolonged and shortened ((5.69 ± 1.33) min vs (13.49 ± 3.43) min vs (3.56 ± 0.76) min, P<0.01); peak RER (1.27 ± 0.07 vs 1.18 ± 0.06 vs 1.33 ± 0.08, P<0.01~P<0.05) and the recovery RER maximum (1.72±0.16 vs 1.61±0.11 vs 1.81±0.14, P<0.01~P<0.05) were significantly decreased and increased. Conclusion: Different work rate increasing rate of CPET significantly change the Peak Work Rate, exercise time, Peak RER, and maximum RER during recovery. The CPET operator should choose an individualized work rate increasing rate that is appropriate for the subject, and also does not use a fixed RER value as a basis for ensuring safety, the subject's extreme exercise, and early termination of exercise.


Assuntos
Teste de Esforço , Insuficiência Cardíaca , Exercício Físico , Frequência Cardíaca , Humanos , Consumo de Oxigênio
9.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 37(2): 120-124, 2021 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-34672148

RESUMO

Objective: To observe the effect of healthy volunteers different work rate increasing rate cardiopulmonary exercise testing (CPET) on the sub-peak parameters . Methods: Twelve healthy volunteers were randomly assigned to a moderate (30 W/min), a relatively low (10 W/min) and relatively high (60 W/min) three different work rate increasing rate CPET on different working days in a week. The core indicators related to CPET sub-peak exercise of 12 volunteers were compared according to standard Methods: anaerobic threshold (AT), oxygen uptake per unit power (ΔVO2/ΔWR), oxygen uptake eficiency plateau,(OUEP), the lowest average of 90 s of carbon dioxide ventilation equivalent (Lowest VE/ VCO2), the slope of carbon dioxide ventilation equivalent (VE/ VCO2 Slope) and intercept and anaerobic threshold oxygen uptake ventilation efficiency value (VO2/ VE@AT) and the anaerobic threshold carbon dioxide ventilation equivalent value (VE/ VCO2@AT). Paired t test was performed on the difference of each parameter in the three groups of different work rate increasing rate. Results: Compared with the relatively low and relatively high work rate increasing rate group, the moderate work rate increasing rate group uptake eficiency plateau, (42.22±4.76 vs 39.54±3.30 vs 39.29±4.29) and the lowest average of 90 s of carbon dioxide ventilation equivalent (24.13±2.88 vs 25.60±2.08 vs 26.06±3.05) was significantly better, and the difference was statistically significant (P<0.05); Compared with the moderate work rate increasing rate group, the oxygen uptake per unit work rate of the relatively low and relatively high work rate increasing rate group increased and decreased significantly ((8.45±0.66 vs 10.04±0.58 vs 7.16±0.60) ml/(min·kg)), difference of which was statistically significant (P<0.05); the anaerobic threshold did not change significantly ((0.87±0.19 vs 0.87±0.19 vs 0.89±0.19) L/min), the difference was not statistically significant (P>0.05). Conclusion: Relatively low and relatively high power increase rate can significantly change the CPET sub-peak sports related indicators such as the effectiveness of oxygen uptake ventilation, the effectiveness of carbon dioxide exhaust ventilation, and the oxygen uptake per unit work rate. Compared with the moderate work rate increasing rate CPET, the lower and higher work rate increasing rate significantly reduces the effectiveness of oxygen uptake ventilation and the effectiveness of carbon dioxide exhaust ventilation in healthy individuals. The standardized operation of CPET requires the selection of a work rate increasing rate suitable for the subject, so that the CPET sub-peak related indicators can best reflect the true functional state of the subject.


Assuntos
Teste de Esforço , Consumo de Oxigênio , Limiar Anaeróbio , Humanos , Troca Gasosa Pulmonar , Ventilação Pulmonar
10.
Acta Radiol ; : 2841851211046332, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34668808

RESUMO

BACKGROUND: The actual role of the coronary microcirculation, which is massively injured by myocardial infarction (MI), in intramyocardial hemorrhage (IMH) pathophysiology is still not fully understood. PURPOSE: To determine the change and distribution of microcirculation of myocardial edema (ME), IMH, MI, and the remote area of early reperfusion using 7.0-T cardiovascular magnetic resonance (CMR) in a rat model of acute MI. MATERIAL AND METHODS: Eight rats with 60-min myocardial ischemia followed by reperfusion were investigated. On days 2 and 7, after the acquisition of T2*-mapping and T2-mapping images, late gadolinium enhancement imaging was performed to evaluate the extent of myocardial ischemia after an injection of Gd-DTPA. On days 3 and 8, after the injection of ultrasmall superparamagnetic iron oxide (USPIO), T2*- and T2-mapping images were acquired. The R2 values of ME, IMH, MI, and remote areas were measured. RESULTS: From days 2 to 3, R2 values increased in the IMH, MI, ME, and remote area (all P < 0.05) following administration of USPIO, while the delta R2 value of IMH and MI was larger than remote area (P < 0.05). From day 7 to day 8, there was no significant difference in the IMH, MI, ME, and remote area (all P > 0.05). CONCLUSION: Microvascular injury of IMH and MI is the most severe among all the studied myocardial injuries in the early reperfusion of MI, while microvascular density decreased during follow-up.

11.
Aging (Albany NY) ; 13(19): 23004-23019, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34609952

RESUMO

OBJECTIVE: Long non-coding RNAs (lncRNAs) exert a critical function in mediating neuropathic pain (NP). MEG3, a novel lncRNA, contributes to astrocyte activation and inflammation. However, its role in NP remains unclear. METHODS: The chronic constriction injury (CCI) method was employed to construct an NP rat model. Astrocyte activation was induced by lipopolysaccharide (LPS). The profiles of MEG3, microRNA (miR)-130a-5p, CXC motif chemokine receptor 12 (CXCL12)/CXC motif chemokine receptor 4 (CXCR4), and the Rac1/NF-κB pathway in CCI rats' spinal cord tissues and astrocytes were monitored by reverse transcription-quantitative PCR (RT-qPCR) and western blot (WB). Pain scores of CCI rats were assessed. Enzyme-linked immunosorbent assay (ELISA) was adopted to monitor neuroinflammation alteration. The glial fibrillary acidic protein (GFAP)-labeled astrocytes were tested by immunohistochemistry (IHC). Bioinformatics, dual-luciferase reporter assay and RNA immunoprecipitation (RIP) were utilized to verify the molecular mechanism between MEG3 and miR-130a-3p. RESULTS: MEG3, CXCL12 and CXCR4 were overexpressed and miR-130a-5p was knocked down in CCI rats and LPS-induced astrocytes. Up-regulating MEG3 aggravated NP, enhanced inflammatory cytokines interleukin-1ß (IL-1ß), tumor necrosis factor (TNF)-α, and interleukin-6 (IL-6) expression and release in CCI rats and LPS-induced astrocytes. Up-regulating miR-130-5p repressed LPS-induced inflammation in astrocytes. AS verified by the dual-luciferase reporter assay and RIP assay, MEG3 sponged miR-130a-5p as a competitive endogenous RNA (ceRNA). What's more, miR-130a-5p up-regulation weakened the MEG3-induced proinflammatory effects on LPS-induced astrocytes. CONCLUSIONS: MEG3 aggravates NP and astrocyte activation via the miR-130a-5p/CXCL12/CXCR4 axis, which is a potential therapeutic target for NP.

12.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 35(9): 1111-1118, 2021 Sep 15.
Artigo em Chinês | MEDLINE | ID: mdl-34523275

RESUMO

Objective: To compare the effectiveness of the femoral neck system (FNS) and inverted triangle cannulated screws (ITCS) for the treatment of Pauwels type Ⅲ femoral neck fractures. Methods: The clinical data of 59 patients with Pauwels type Ⅲ femoral neck fractures treated between May 2019 and November 2020 were retrospectively analysed. The patients were divided into FNS group (28 cases) and ITCS group (31 cases) according to the different internal fixation. There was no significant difference in gender, age, affected side, body mass index, cause of injury, smoking history, alcohol abuse history, Pauwels angle, Garden classification, AO/Orthopaedic Trauma Association (AO/OTA) classification, and time from injury to operation between the two groups ( P>0.05). The operation time, incision length, intraoperative blood loss, extra assisted reduction procedures (Kirschner wire prying reduction or open reduction), hospitalization stay, and early complications were recorded and compared between the two groups. Garden index and Haidukewych score were used to evaluate fracture reduction. Fracture healing time, lateral thigh irritation, time of partial or total weight-bearing postoperatively, shortening length and degree of femoral neck, change of caput-collum-diaphysis (CCD) angle (the difference of CCD angle between immediate after operation and last follow-up), incidence of osteonecrosis of femoral head and revision surgery were recorded and compared between the two groups. Hip joint function were evaluated by Harris score. Results: The operation time of FNS group was significantly shorter than ITCS group, and the incision length was significantly longer than ITCS group ( P<0.05). There was no significant difference in intraoperative blood loss, assisted reduction, Garden index, Haidukewych score, and hospitalization stay between the two groups ( P>0.05). All the incisions healed by first intention. There were 2 deep vein thrombosis in the FNS group and 1 pulmonary infection and 1 deep vein thrombosis in the ITCS group. No significant difference was found in the incidence of early postoperative complications (7.1% vs. 6.5%) between the two groups ( P=1.000). Patients in both groups were followed up 3-14 months, and there was no significant difference in follow-up time between the two groups ( t=-0.553, P=0.582). The fracture healing time, Harris score, and the partial weight-bearing time after operation of the FNS group were significantly better than those of the ITCS group ( P<0.05). However, there was no significant difference in total weight-bearing time between the two groups ( Z=-1.298, P=0.194). No lateral thigh irritation was found in the FNS group, while 10 patients in the ITCS group had lateral thigh irritation, and the incidence between the two groups (0 vs. 32.3%) was significant ( P=0.001). At last follow-up, the shortening length and degree of femoral neck and the change of CCD angle in FNS group were significantly less than those in ITCS group ( P<0.05). There was no patient with osteonecrosis of femoral head or reoperation in the FNS group, while 4 patients in the ITCS group underwent reoperation (including 2 cases of osteonecrosis of the femoral head). However, the incidences (0 vs. 6.5%; 0 vs.12.9%) between the two groups were not significant ( P=0.493; P=0.114). Conclusion: Using FNS to treat Pauwels type Ⅲ femoral neck fracture is simple as well as able to reduce the shortening of the femoral neck and the change of the CCD angle. Also, FNS is conducive to the recovery of hip joint function, which should be considered as a new choice for the treatment of young femoral neck fracture patients.


Assuntos
Fraturas do Colo Femoral , Parafusos Ósseos , Fraturas do Colo Femoral/cirurgia , Colo do Fêmur , Fixação Interna de Fraturas , Humanos , Estudos Retrospectivos , Resultado do Tratamento
13.
Nat Commun ; 12(1): 5350, 2021 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-34504089

RESUMO

Relationships between biodiversity and multiple ecosystem functions (that is, ecosystem multifunctionality) are context-dependent. Both plant and soil microbial diversity have been reported to regulate ecosystem multifunctionality, but how their relative importance varies along environmental gradients remains poorly understood. Here, we relate plant and microbial diversity to soil multifunctionality across 130 dryland sites along a 4,000 km aridity gradient in northern China. Our results show a strong positive association between plant species richness and soil multifunctionality in less arid regions, whereas microbial diversity, in particular of fungi, is positively associated with multifunctionality in more arid regions. This shift in the relationships between plant or microbial diversity and soil multifunctionality occur at an aridity level of ∼0.8, the boundary between semiarid and arid climates, which is predicted to advance geographically ∼28% by the end of the current century. Our study highlights that biodiversity loss of plants and soil microorganisms may have especially strong consequences under low and high aridity conditions, respectively, which calls for climate-specific biodiversity conservation strategies to mitigate the effects of aridification.


Assuntos
Biodiversidade , Clima Desértico , Fungos/metabolismo , Desenvolvimento Vegetal , Plantas/metabolismo , Solo/química , China , Ecossistema , Fungos/classificação , Fungos/crescimento & desenvolvimento , Geografia , Concentração de Íons de Hidrogênio , Modelos Teóricos , Plantas/classificação , Microbiologia do Solo , Especificidade da Espécie , Água/metabolismo
14.
ACS Appl Mater Interfaces ; 13(39): 46291-46302, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34558902

RESUMO

The current clinical performance of chemotherapy is far from satisfactory, greatly limited by insufficient delivery efficacy and serious systemic side effects. Dimeric prodrug systems are emerging as valuable strategies for boosting the antitumor outcome. Here, dimeric paclitaxel prodrugs were synthesized with different bridged linkers, and the formed prodrug nanoparticles possessed excellent colloidal stability and ultrahigh drug content. The diselenide bond containing paclitaxel prodrugs could respond to a redox-heterogeneous intracellular microenvironment for on-demand drug release and subsequently show a selective cytotoxicity toward tumor cells against normal cells. Furthermore, the optimal carrier materials were screened out according to their contribution on stability, endocytosis, cytotoxicity, biodistribution, and antitumor efficacy. Compared with DSPE-PEG, human serum albumin, and Fe-tannic acid-based complex, F127 anchored dimeric paclitaxel nanoformulations exhibited preferential tumor accumulation and potent anticancer effect. Our present work provides deep insight into the development of advanced nanoformulations with comprehensive advantages for enhancing cancer therapy.

15.
BMC Plant Biol ; 21(1): 423, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34535087

RESUMO

BACKGROUND: The GRAS gene family plays crucial roles in multiple biological processes of plant growth, including seed development, which is related to seedless traits of litchi (Litchi chinensis Sonn.). However, it hasn't been fully identified and analyzed in litchi, an economic fruit tree cultivated in subtropical regions. RESULTS: In this study, 48 LcGRAS proteins were identified and termed according to their chromosomal location. LcGRAS proteins can be categorized into 14 subfamilies through phylogenetic analysis. Gene structure and conserved domain analysis revealed that different subfamilies harbored various motif patterns, suggesting their functional diversity. Synteny analysis revealed that the expansion of the GRAS family in litchi may be driven by their tandem and segmental duplication. After comprehensively analysing degradome data, we found that four LcGRAS genes belong to HAM subfamily were regulated via miR171-mediated degradation. The various expression patterns of LcGRAS genes in different tissues uncovered they were involved in different biological processes. Moreover, the different temporal expression profiles of LcGRAS genes between abortive and bold seed indicated some of them were involved in maintaining the normal development of the seed. CONCLUSION: Our study provides comprehensive analyses on GRAS family members in litchi, insight into a better understanding of the roles of GRAS in litchi development, and lays the foundation for further investigations on litchi seed development.


Assuntos
Litchi/genética , Proteínas de Plantas/genética , Sementes/crescimento & desenvolvimento , Mapeamento Cromossômico , Regulação da Expressão Gênica de Plantas , Litchi/crescimento & desenvolvimento , MicroRNAs , Família Multigênica , Filogenia , RNA de Plantas , Sementes/genética , Sintenia , Fatores de Transcrição/genética
16.
Front Plant Sci ; 12: 629776, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34557205

RESUMO

Apple replant disease (ARD), incited by a pathogen complex including Pythium ultimum, causes stunted growth or death of newly planted trees at replant sites. Development and deployment of resistant or tolerant rootstocks offers a cost-effective, ecologically friendly, and durable approach for ARD management. Maximized exploitation of natural resistance requires integrated efforts to identify key regulatory mechanisms underlying resistance traits in apple. In this study, miRNA profiling and degradome sequencing identified major miRNA pathways and candidate genes using six apple rootstock genotypes with contrasting phenotypes to P. ultimum infection. The comprehensive RNA-seq dataset offered an expansive view of post-transcriptional regulation of apple root defense activation in response to infection from P. ultimum. Several pairs of miRNA families and their corresponding targets were identified for their roles in defense response in apple roots, including miR397-laccase, miR398-superoxide dismutase, miR10986-polyphenol oxidase, miR482-resistance genes, and miR160-auxin response factor. Of these families, the genotype-specific expression patterns of miR397 indicated its fundamental role in developing defense response patterns to P. ultimum infection. Combined with other identified copper proteins, the importance of cellular fortification, such as lignification of root tissues by the action of laccase, may critically contribute to genotype-specific resistance traits. Our findings suggest that quick and enhanced lignification of apple roots may significantly impede pathogen penetration and minimize the disruption of effective defense activation in roots of resistant genotypes. The identified target miRNA species and target genes consist of a valuable resource for subsequent functional analysis of their roles during interaction between apple roots and P. ultimum.

17.
BMC Cardiovasc Disord ; 21(1): 455, 2021 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-34548012

RESUMO

OBJECTIVE: To investigate the relationship between ST-segment resolution (STR) and myocardial scar thickness after percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarction (STEMI). METHODS: Forty-two STEMI patients with single-branch coronary artery stenosis or occlusion were enrolled. ST-segment elevations were measured at emergency admission and at 24 h after PCI. Late gadolinium-enhanced cardiac magnetic resonance imaging (CMR-LGE) was performed 7 days after PCI to evaluate myocardial scars. Statistical analyses were performed to assess the utility of STR to predict the development of transmural (> 75%) or non-transmural (< 75%) myocardial scars, according to previous study. RESULTS: The sensitivity and specificity of STR for predicting transmural scars were 96% and 88%, respectively, at an STR cut-off value of 40.15%. The area under the curve was 0.925. Multivariate logistic proportional hazards regression analysis disclosed that patients with STR < 40.15% had a 170.90-fold higher probability of developing transmural scars compared with patients with STR ≥ 40.15%. Pearson correlation and linear regression analyses showed STR percentage was significantly associated with myocardial scar thickness and size. CONCLUSION: STR < 40.15% at 24 h after PCI may provide meaningful diagnostic information regarding the extent of myocardial scarification in STEMI patients.

18.
Plant J ; 108(4): 1037-1052, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34519122

RESUMO

Rambutan is a popular tropical fruit known for its exotic appearance, has long flexible spines on shells, extraordinary aril growth, desirable nutrition, and a favorable taste. The genome of an elite rambutan cultivar Baoyan 7 was assembled into 328 Mb in 16 pseudo-chromosomes. Comparative genomics analysis between rambutan and lychee revealed that rambutan chromosomes 8 and 12 are collinear with lychee chromosome 1, which resulted in a chromosome fission event in rambutan (n = 16) or a fusion event in lychee (n = 15) after their divergence from a common ancestor 15.7 million years ago. Root development genes played a crucial role in spine development, such as endoplasmic reticulum pathway genes, jasmonic acid response genes, vascular bundle development genes, and K+ transport genes. Aril development was regulated by D-class genes (STK and SHP1), plant hormone and phenylpropanoid biosynthesis genes, and sugar metabolism genes. The lower rate of male sterility of hermaphroditic flowers appears to be regulated by MYB24. Population genomic analyses revealed genes in selective sweeps during domestication that are related to fruit morphology and environment stress response. These findings enhance our understanding of spine and aril development and provide genomic resources for rambutan improvement.

19.
Huan Jing Ke Xue ; 42(9): 4211-4221, 2021 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-34414719

RESUMO

Hanjiang River is the main water source and influence area of the Middle Route of the South to North Water Transfer Project. In recent years, the water quality and ecological environment in the middle and lower reaches of the Hanjiang River has become seriously degraded and water blooms occur frequently. Scientific identification of the temporal and spatial variations in water environment quality (and the main driving factors) has become an important management requirement for optimizing the upstream water transfer project. The temporal and spatial variations and influencing factors of water quality in the Hanjiang River basin were systematically analyzed, based on multi-source data and using the Daniel trend test, Mann Kendall test, K-means cluster analysis, dissimilarity analysis, and redundancy analysis. Results showed that: ① in recent years, the main stream of the Hanjiang River had generally good water quality, which was generally classified as class Ⅱ of GB 3838-2002, while the water quality of some sections in the middle and lower reaches was classified as class Ⅲ. However, the total phosphorus (TP) and total nitrogen (TN) load was relatively high, with 10 stations in the Hanjiang River basin showing averaged concentrations of 0.028-0.263 mg·L-1 and 0.630-1.852 mg·L-1, respectively, during 2014-2018. ② From 2004 to 2018, TP and TN at Zongguan station did not show significant variation, and other water quality indexes did not exhibit any regular patterns. The concentrations of TN, NH4+-N, and BOD5 in the dry season were higher than those in the wet season. In the wet season. the permanganate index showed different variation patterns, while TP concentration did not decrease significantly. ③ Different sections showed obvious differences in the variation of water quality indexes. However, the ten stations can be clustered into three categories: the upstream stations showed the best water quality, followed by the middle reaches, and the downstream stations showed the worst. The water quality at Xiaohe station improved significantly over the study period, which may be related to protection measures implemented in recent years, such as source control, emission reduction, and removal of aquaculture. ④ Water discharge and temperature were important factors affecting the water quality of the three regions in Hanjiang River. According to redundancy analysis, the contribution of discharge to water quality in the upstream and downstream areas was much larger, while the contribution of water temperature was greatest in the middle reaches of the river.


Assuntos
Monitoramento Ambiental , Qualidade da Água , Nitrogênio/análise , Fósforo/análise , Rios
20.
J Phys Chem Lett ; 12(33): 7901-7907, 2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34382792

RESUMO

Moiré superlattices (MSLs) of two-dimensional (2D) van der Waals materials have attracted considerable attention in recent years; however, studies of bottom-up growth of twisted MSL structures via solution-processed crystallization are rarely reported. Through facile one-pot solvothermal synthesis, here we demonstrate a nonclassical surfactant/nanosheet-co-mediated crystallization pathway for formation of MSL structures with two models of SnS2 and SnSe2. Our experimental results reveal that attractive interactions between 2D inorganic building blocks and surfactant organic molecules during the initial stage of crystallization are crucial to drive surfactant-covered nanosheets to crystallize into molecule-intercalated nanosheet aggregates. Under the high-pressure condition, further crystallograpic fusion can occur if the reaction time is prolonged, which alters the interactions of adjacent layers during the coalescence of small-grain-size 2D domains due to insertion of foreign molecules, leading to interlayer rotations. This work uncovers an interesting organic-inorganic cocrystallization growth mode and provides a novel pathway for large-scale fabrication of MSLs.

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