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1.
Methods Mol Biol ; 2174: 89-118, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32813246

RESUMO

With the advances in sequencing technology and transcriptome analysis, it is estimated that up to 75% of the human genome is transcribed into RNAs. This finding prompted intensive investigations on the biological functions of noncoding RNAs and led to very exciting discoveries of microRNAs as important players in disease pathogenesis and therapeutic applications. Research on long noncoding RNAs (lncRNAs) is in its infancy, yet a broad spectrum of biological regulations has been attributed to lncRNAs. Here, we provide a collection of detailed experimental protocols for lncRNA studies, including lncRNA immunoprecipitation, lncRNA pull-down, lncRNA northern blot analysis, lncRNA in situ hybridization, and lncRNA knockdown. We hope that the information included in this chapter can speed up research on lncRNAs biology and eventually lead to the development of clinical applications with lncRNA as novel prognostic markers and therapeutic targets.

2.
J Cell Physiol ; 236(2): 931-945, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32583428

RESUMO

Ischemia reperfusion (I/R)-induced acute kidney injury (AKI) is a common and serious condition. Irisin, an exercise-induced hormone, improves mitochondrial function and reduces reactive oxygen species (ROS) production. Glutathione peroxidase 4 (GPX4) is a key regulator of ferroptosis and its inactivation aggravates renal I/R injury by inducing ROS production. However, the effect of irisin on GPX4 and I/R-induced AKI is still unknown. To study this, male adult mice were subjected to renal I/R by occluding bilateral renal hilum for 30 min, which was followed by 24 hr reperfusion. Our results showed serum irisin levels were decreased in renal I/R mice. Irisin (250 µg/kg) treatment alleviated renal injury, downregulated inflammatory response, improved mitochondrial function, and reduced ER stress and oxidative stress after renal I/R, which were associated with upregulation of GPX4. Treated with RSL3 (a GPX4 inhibitor) abolished irisin's protective effect. Thus, irisin attenuates I/R-induced AKI through upregulating GPX4.

3.
Sci Total Environ ; 752: 141854, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32889279

RESUMO

Herein, ß-cyclodextrin (ß-CD) was efficiently grafted onto rice husk-based celluloses using different cross-linking agents of epichlorohydrin (EPI) and glutaraldehyde (GA). By feat of microwave irradiation, the functionalization procedure was completed in 17 min, and the synthesized RHEPIMWß-CD and RHGAMWß-CD exhibited fast adsorption equilibrium for Pb(II) within 20 min, excellent monolayer adsorption capacities of 216.06 and 279.08 mg g-1 across an extensive pH scope of 3.0-6.0, unaffected affinity to Pb(II) during the existence of co-existing ions, superior reusability with over 81% and 87% of Pb(II) uptake sustained for four adsorption-desorption cycles. Thermodynamic parameters implied that the uptake process of Pb(II) occurred spontaneously (-ΔG0) with an endothermic characteristic (+ΔH0). Furthermore, electrostatic attraction and complexation were demonstrated to enhance the Pb(II) uptake onto the RHEPIMWß-CD and RHGAMWß-CD. In fix-bed columns, these two adsorbents also efficiently eliminated Pb(II) under various flow rates with experimental breakthrough curves well simulated by Thomas and Yoon-Nelson models. Significantly, the RHEPIMWß-CD and RHGAMWß-CD could effectively purify acid battery effluent containing Pb(II) for meeting regulatory requirement. Overall, the fast fabrication, excellent adsorption and recycling performance facilitate the development of tailored adsorbents for Pb(II) elimination in wastewater.

4.
Protein Expr Purif ; 177: 105761, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32956801

RESUMO

Development of new affinity tags is important for recombinant protein expression and purification. Based on our earlier work, we devised an affinity tag by addition of two cysteine residues onto the N- and C-termini of the Fc-III peptide and designated as the Fc-III-4C tag, in which four cysteine residues form two disulfide linkages. The binding affinity of Fc-III-4C tag to human IgG is measured as 2.28 nM (Kd) and is 100 times higher than that of the Fc-III tag to IgG. Fc-III-4C tagged carbonic anhydrase (CA) can be effectively purified with IgG-immobilized beads, and Fc-III-4C tag does not possess adverse effects on the structure and stability of CA. Furthermore, the Fc-III-4C tagged protein binds to multiple transition metal ions, which enhances activities of enzymes that use metal ions as co-factors. These results suggest that Fc-III-4C tag is a useful tool for expression and purification of recombinant proteins and enhances the activities of some fusion proteins that use Zn2+ or Cu2+ as cofactors.

5.
J Nanosci Nanotechnol ; 21(1): 195-211, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33213623

RESUMO

Understanding the controls on composition changes and porosity evolution in the critical zone of shale remains a major challenge. The aim of the present study is to develop a model of the changes in mineral compositions, chemical compositions and nanopore formation in shale during the initial weathering stage. To understand these processes, we selected a Silurian shale profile rich in pyrite and organic matter located in South China. Based on X-ray diffraction (XRD) and bulk elemental data, the variations in mineralogical and chemical compositions with depth were studied. To characterize the full pore size spectrum and to gain insight into the nature of secondary pores and their relationship with weathering, nuclear magnetic resonance (NMR) measurements and petrographic observations were combined with scanning electron microscopy (SEM) imaging. The results show that Al and K are enriched slightly, while Ca and Na are depleted in the upper part of the weathering profile. Si, Mn and Ti are relatively stable from the bottom to the top of the profile. Quartz, feldspar, mica, illite and chlorite are the main minerals in the parent rock, and they are relatively stable along the profile. The rock density gradually decreases from 2.6 g/cm³ to 2.1 g/cm³ from the bottom to the top, and the color of the shales changes from black to grayish yellow, but no secondary minerals are detected. The chemical weathering of black shale is dominated by the oxidation of pyrite and organic matter, giving rise to color variation and nanopore formation. The increase in interparticle pores at the nanometer-micron scale is initiated by the dissolution of easily weathered components such as organic matter and pyrite. The removal of clay minerals and tiny particles by groundwater seepage may be the main cause of porosity enhancement during the initial weathering stage. This study suggests that nanoporosity may play an important role in the process of fluid-rock interaction within black shale during the initial weathering stage.

6.
Artigo em Inglês | MEDLINE | ID: mdl-33188921

RESUMO

STUDY OBJECTIVE: To investigate pregnancy and obstetric outcomes of patients with intrauterine adhesions (IUAs) following treatment with in vitro fertilization-intracytoplasmic sperm injection (IVF-ICSI) and fresh embryo transplantation after transcervical resection of adhesions (TCRA). DESIGN: Retrospective cohort study. SETTING: University-based reproductive medical center. PATIENTS: 535 IUA patients with history of TCRA and 1605 matched patients without history of IUAs underwent IVF-ICSI and received fresh embryo transfers. INTERVENTIONS: Between January 2014 and December 2018, all patients underwent IVF-ICSI treatment and received fresh embryo transfers. MEASUREMENTS AND MAIN RESULTS: The patients in the TCRA group were matched with the control group according to strict criteria. Pregnancy and obstetric outcomes were compared. There were no significant differences in clinical pregnancies, ectopic pregnancies, live births, preterm births, and obstetric outcomes between the two groups (P>0.05). However, the TCRA group had a higher risk of miscarriage than the control group (P=0.048). CONCLUSIONS: TCRA improved the reproductive outcomes of IUA patients, but the risk of miscarriage was higher than that in the general population. To avoid miscarriage, careful monitoring is critical for pregnant patients with a history of TCRA who undergo embryo transfers during IVF treatment.

7.
Retina ; 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33181761

RESUMO

PURPOSE: To investigate the progression of myopic maculopathy (MM) and associated factors in highly myopic Chinese children. METHODS: In this retrospective observational case series, biometric fundus features were morphometrically measured on photographs. Myopic maculopathy was defined as recommended by the Meta-analysis of Pathologic Myopia Study Group. RESULTS: The study included 274 children (mean age:11.7±2.5 years; mean refractive error:-7.66±1.87 diopters) with a mean follow-up of 4.9±1.2 years. MM progression was detected in 52 eyes (18.9%; 95% confidence interval [CI]:14.3%,23.7%). In multivariable analysis, MM progression was associated with a decrease in refractive error (odds ratio [OR]:0.72;95%CI:0.56,0.92;P<0.001) (i.e. higher myopization) and enlargement of parapapillary gamma zone (OR:7.68;95%CI:1.63,36.2;P=0.002). Incident peripapillary diffuse choroidal atrophy noted in 47 of 236 eyes (20.0%; 95%CI, 14.8%-25.2%), was correlated with a decrease in refractive error (OR:0.70;95%CI:0.54,0.92;P=0.009) (i.e., higher myopization) and greater gamma zone enlargement (OR:8.28;95%CI:1.33,51.7;P=0.02). CONCLUSIONS: Myopia in schoolchildren may have a considerable risk of progressing to MM. Enlargement of parapapillary gamma zone was a main independent risk factor.

8.
Clin Nutr ; 2020 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-33183882

RESUMO

BACKGROUND & AIMS: The roles of obesity and weight management in colorectal cancer (CRC) recurrence and survival have gained a considerable amount of attention. However, whether a change in weight affects the risk of recurrence and death remains unclear. METHODS: A retrospective study was conducted using Kaplan-Meier curves, multivariable Cox proportional hazards models, and restricted cubic splines in 902 patients with stage Ⅱ and Ⅲ CRC to investigate the impact of the preoperative BMI and change in weight during postoperative chemotherapy on disease-free survival (DFS) and overall survival (OS). RESULTS: The lowest risk of cancer events (recurrence/metastasis and new CRC cases) and death occurred in patients who had a normal weight (BMI range from 18.5 to 23.9 kg/m2) or had weight gain of < 5%; the patients who were underweight (BMI ≤ 18.5 kg/m2) or overweight/obese (BMI ≥ 24.0 kg/m2) and had weight loss or weight gain of ≥ 5% had a higher risk of cancer events and death. The association between preoperative BMI and the risk of cancer events and death exhibited U-shaped curves; the inflection points were at BMI = 24 kg/m2 and BMI = 25 kg/m2 for the risk of cancer events and death, respectively. The association between the change in weight and risk of death also exhibited a U-shaped curve, while the association between the change in weight and risk of cancer events was nearly linear. Multivariable Cox proportional hazards models showed that the preoperative BMI and change in weight played bidirectional roles in both the OS and DFS. CONCLUSIONS: An obesity paradox exists in patients with CRC, with both weight loss and excessive weight gain being detrimental. Patients with CRC may require a reasonable weight management program, and gaining < 5% of the preoperative weight might be an appropriate goal at 6 months after surgery.

9.
Artigo em Inglês | MEDLINE | ID: mdl-33177434

RESUMO

Depression and anxiety, which may influence antiretroviral therapy (ART) medication adherence, are prevalent among persons living with HIV (PLWH) in China. This parallel two-arm clinical controlled trial aimed to examine the effects of a nurse-delivered cognitive behavioral intervention (CBI) on depression, anxiety, and ART medication adherence in Chinese PLWH. Using in-person and online recruitment, 140 PLWH ages 18 years and older who were undergoing ART and had a Patient Health Questionnaire-4 score of ≥2 were assigned to the 10-week-long CBI group or the routine follow-up group according to their preference. Outcomes were measured at baseline, postintervention, and 6-month follow-up. Results showed significant intervention effects on depression maintained until the 6-month follow-up. Although anxiety and ART medication adherence did not show robust effects between conditions, amelioration trends for these outcomes were also found. Our study demonstrated that the nurse-delivered CBI could help Chinese PLWH ameliorate depression.

10.
RNA Biol ; : 1-12, 2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-33151124

RESUMO

Treatment of central nervous system (CNS) demyelination is greatly hindered by lack of the knowledge regarding to underlying molecular mechanisms as well as therapeutic agents. Here, we report a novel small molecule agent, gastrodin (GAS), which can significantly promote CNS myelination in in vivo mice models. By using high-throughput sequencing analysis, we discover a key long non-coding RNA Gm7237 that can enhance CNS myelination and is up-regulated by GAS. Through using bioinformatic analysis and experimental validations, we further unravel that microRNA-142a (miR-142a) and its target myelin gene regulatory factor (MRF) is under the direct regulation by Gm7237. Finally, we demonstrate that Gm7237/miR-142a/MRF axis is the key pathway involved in CNS myelination mediated by GAS. Overall, our results provide not only a novel agent for therapeutic treatment of CNS demyelination but also a molecular basis responsible for GAS-promoted CNS myelination.

11.
Sci Total Environ ; : 143152, 2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-33139001

RESUMO

Exposure to silica nanoparticles (SiNPs) has been suggested to cause physical disorders, yet the effects of SiNPs on female reproduction have not been illustrated. This study was implemented to explore the reproductive toxicity of SiNPs on female and reveal its underlying mechanisms. Methodologically, the fluorescein isothiocyanate (FITC)-SiNPs were synthesized by coupling with FITC and then used to track the biodistribution of SiNPs in vitro and in vivo. In total, 30 mice were intratracheally injected 0.25 g of FITC-SiNPs, and 6 mice injected with the same volume of saline were used as controls. The results showed that SiNPs penetrated the cellular membrane, triggering apoptosis and inhibiting proliferation, tube formation, and invasion of trophoblast. Mechanistically, SiNPs was demonstrated to dysregulate Fbp2, Cpt1a, Scd1, and Pfkl, and further induced accumulation of pyruvate and fatty acid in mitochondria through the AMPK signaling pathway, which finally activated the Caspase-3-dependent apoptosis. Consistently, the similar alterations of these genes were detected in vivo, and the uterine inflammatory infiltration aggravated with the extension of the observation duration. These results suggested that SiNPs induced trophoblast apoptosis and uterine inflammation, and ultimately caused acute reproductive toxicity on female. The underlying mechanism might be explained by the dysregulation of Fbp2/Cpt1a/Pfkl/Scd1 axis, which promoted the overload of glucose and lipid through the AMPK signaling pathway. These findings were of great significance to guide a comprehensive understanding of the reproductive toxicity of SiNPs as well as the development of environmental standards.

12.
BMC Neurol ; 20(1): 424, 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33225904

RESUMO

BACKGROUND: Globally, rates of ischemic stroke (IS) have been rising among young adults. This study was designed to identify risk factors associated with IS incidence in young adults unaffected by hypertension or diabetes. METHODS: This was a retrospective case-control study of early-onset IS patients without diabetes and hypertension. Control patients were matched with healthy individuals based upon sex, age (±2 years), and BMI (±3 kg/m2) at a 1:3 ratio. Sociodemographic, clinical, and risk factor-related data pertaining to these patients was collected. The association between these risk factors and IS incidence was then assessed using conditional logistic regression models. RESULTS: We recruited 60 IS patients and 180 controls with mean ages of 44.37 ± 4.68 and 44.31 ± 4.71 years, respectively, for this study. Relative to controls, IS patients had significantly higher total cholesterol (TG), homocysteine (HCY), white blood cell (WBC), absolute neutrophil count (ANC), systolic blood pressure (SBP), and diastolic blood pressure (DBP) levels, and significantly lower high-density lipoprotein cholesterol (HDL-C) and triglyceride cholesterol (TC), free triiodothyronine (FT3), and free thyroxine (FT4) levels (all P < 0.05). After controlling for potential confounding factors, HCY and ANC were found to be significantly positively associated with IS incidence (OR 1.518, 95%CI 1.165-1.977, P = 0.002 and OR 2.418, 95%CI 1.061-5.511, P = 0.036, respectively), whereas HDL-C and FT3 levels were negatively correlated with IS incidence (OR 0.001, 95%CI 0.000-0.083, P = 0.003 and OR 0.053, 95%CI 0.008-0.326, P = 0.002, respectively). CONCLUSIONS: In young non-diabetic and non-hypertensive patients, lower HDL-C and FT3 levels and higher HCY and ANC levels may be associated with an elevated risk of IS. Additional prospective studies of large patient cohorts will be essential to validate these findings.

13.
Bioorg Med Chem Lett ; 30(24): 127652, 2020 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-33130293

RESUMO

Hypoxia-inducible factor 1α (HIF-1α) is a known regulator of tumor cell proliferation, migration, and angiogenesis. The presence of a high concentration of HIF-1α is positively correlated with the severity of cancer. Therefore, the inhibition of this pathway represents an important therapeutic target for the treatment of various types of cancer. Here, we designed and synthesized 30 panaxadiol (PD) derivatives and evaluated their inhibitory activities against HIF-1α transcription. Of these, compound 3l exhibited the most promising inhibitory activity (IC50 = 3.7 µM) and showed significantly decreased cytotoxicity compared with PD. Compound 9e exhibited the strongest cytotoxic effect and may be considered for further preclinical development.

15.
New Phytol ; 2020 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-33205416

RESUMO

Arbuscular mycorrhizal (AM) fungi gain access to nutrient patches outside the rhizosphere by producing an extensive network of fine hyphae. Here, we focused on establishing the mechanism by which AM fungal hyphae reach discrete organic patches with a cohort of functional bacteria transported in a biofilm on their surface. We investigated the mechanisms and impact of the translocation of phosphate solubilizing bacteria (PSB) along AM fungal hyphae in bespoke microcosms. An in vitro culture experiment was also conducted to determine the direct impact of hyphal exudates of AM fungi upon the growth of PSB. The extraradical hyphae of AM fungi can transport PSB to organic phosphorus (P) patches and enhance organic P mineralization both under in vitro culture and soil conditions. Bacteria move in a thick water film formed around fungal hyphae. However, the bacteria cannot be transferred to the organic P patch without an energy source in the form of hyphal exudates. Our results could be harnessed to better manage plant microbe interactions and improve the ability of biological inocula involving AM fungi and bacteria to enhance the sustainability of agricultural crops in P limited conditions.

16.
Biochem Pharmacol ; : 114318, 2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33159967

RESUMO

Esophageal squamous cell carcinoma (ESCC) is one of the most common types of cancer in China, with poor prognosis and lack of effective targeted therapy. It has been reported that ibrutinib possesses anticancer activity in ESCC with MYC and/or ERBB2 amplification. Here we explored the synergistic antitumor effect of a novel multi-kinase inhibitor APG-2449 with ibrutinib in ESCC and clarified the mechanism of the combination effect through in vitro and in vivo experiment. We found that APG-2449 exerted antitumor effect in ESCC. APG-2449 combined with ibrutinib showed synergistic inhibition of cell viability in ESCC cell lines. APG-2449 combined with ibrutinib dramatically inhibited the proliferation and migration of ESCC cells. Furthermore, we observed that ibrutinib combined with APG-2449 could induce more cancer cells arrested in the G1/S phase and apoptosis. In terms of mechanism, ibrutinib alone could decrease the phosphorylation level of EGFR and its downstream pathway of MEK/ERK. The combination therapy of APG-2449 and ibrutinib could significantly down-regulate the phosphorylation level of MEK/ERK and AKT. In ESCC xenotransplantation models, single therapy with either ibrutinib or APG-2449 was equivalent in delaying tumor growth, while the combination therapy suppressed tumor growth more significantly. Our data strongly suggest that the combination therapy of APG-2449 and ibrutinib can provide an effective therapeutic strategy for ESCC patients, which deserved further clinical investigation.

17.
Ann Surg Oncol ; 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33230746

RESUMO

BACKGROUND: To investigate the clinical feasibility of preoperative routine clinical dynamic Gd-EOB-DTPA-enhanced MRI alone to predict post-hepatectomy liver failure (PHLF) in patients with hepatocellular carcinoma (HCC). METHODS: 116 patients with HCC who underwent liver resection in Southwest Hospital from 2014 through 2017 were selected in this retrospective cohort study. The remnant function (RF) of the liver RFUR and RFRE15 were calculated by the sum of the uptake rate (UR) or relative enhancement at 15 min (RE15) from dynamic Gd-EOB-DTPA-enhanced MR images in the remnant liver regions, and standardized by standard liver volume (SLV) to generate sRFUR (standardized RFUR) and sRFRE15 (standardized RFRE15). Student's t test or Mann-Whitney U test, logistic regression, and ROC analyses were used to test the associations of preoperative RFUR, sRFUR, RFRE15, sRFRE15, the remnant liver volume (RLV)/SLV, ICG retention rate at 15 min (ICG R15) and sRFICG-K [ICG clearance rate (ICG-K) × RLV/SLV] with PHLF. RESULTS: 28 patients were found to have PHLF, who showed lower RFUR, sRFUR, RFRE15, sRFRE15, RLV/SLV, sRFICG-K, and higher ICG R15 than patients without PHLF (p < 0.001 for all). After adjusting for clinical parameters, RFUR (p = 0.001), sRFUR (p = 0.001), RFRE15 (p = 0.002), or sRFRE15 (p = 0.003) was found to be independently significant indicator in multivariable logistic regression, respectively. RFUR (0.882) and sRFUR (0.882) had larger AUCs than RLV/SLV (0.731, p = 0.008; p = 0.005), ICG R15 (0.765, p = 0.039; p = 0.044) and sRFICG-K (0.767, p = 0.031; p = 0.023). RFRE15 (0.845) and sRFRE15 (0.839) had larger AUCs than RLV/SLV (0.731, p = 0.027; p = 0.025). CONCLUSIONS: The remnant liver function parameters preoperatively estimated from a routine clinical dynamic Gd-EOB-DTPA-enhanced MRI protocol can predict PHLF in patients with HCC, and may be better predictors than conventional methods.

18.
Int J Neurosci ; : 1-13, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33174773

RESUMO

PURPOSE: The aim of the current study was to explore the role of the basal forebrain (BF) in propofol anaesthesia. METHODS: In the present study, we observed the neural activities of the BF during propofol anaesthesia using calcium fibre photometry recording. Subsequently, ibotenic acid was injected into the BF to verify the role of the BF in propofol anaesthesia. Finally, to test whether GABAA receptors in the BF were involved in modulating propofol anaesthesia, muscimol (GABAA receptor agonist) and gabazine (GABAA receptor antagonist) were microinjected into the BF. Cortical electroencephalogram (EEG), time to loss of righting reflex (LORR), and recovery of righting reflex (RORR) under propofol anaesthesia were recorded and analysed. RESULTS: The activity of BF neurons was inhibited during induction of propofol anaesthesia and activated during emergence from propofol anaesthesia. In addition, non-specifical lesion of BF neurons significantly prolonged the time to RORR and increased delta power in the frontal cortex under propofol anaesthesia. Next, microinjection of muscimol into the BF delayed emergence from propofol anaesthesia, increased delta power of the frontal cortex, and decreased gamma power under propofol anaesthesia. Conversely, infusion of gabazine accelerated emergence times and decreased EEG delta power. CONCLUSIONS: The basal forebrain is involved in modulating frontal cortex delta activity and emergence from propofol anaesthesia. Additionally, the GABAA receptors in the basal forebrain are involved in regulating emergence propofol anaesthesia.

19.
Poult Sci ; 99(11): 5827-5837, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33142500

RESUMO

This study investigated the effects of dietary corn-resistant starch on lipid metabolism of broilers and its potential relationship with cecal microbiota modulation. A total of three hundred twenty 1-day-old male broilers were randomly assigned into 5 dietary treatments: 1 normal corn-soybean (NC) diet, 1 corn-soybean-based diet supplementation with 20% corn starch (CS), and 3 corn-soybean-based diets supplementation with 4, 8, and 12% corn resistant starch (RS) (identified as 4%RS, 8%RS, and 12%RS, respectively). Each group had 8 replicates with 8 broilers per replicate. The experiment lasted 21 d. The results showed that the abdominal fat percentage were lower in birds from 8%RS and 12%RS groups (0.75 and 0.58%, respectively) than those from NC and CS groups (1.20 and 1.28%, respectively; P < 0.05). The birds from 8%RS and 12%RS groups exhibited lower concentrations of blood triglyceride and nonestesterified fatty acid than those in the NC and CS groups (P < 0.05). Moreover, birds fed diets supplementation with 12% RS decreased the relative mRNA expressions of peroxisome proliferator-activated receptor gamma, ATP citrate-lyase, fatty acid synthase, and acetyl-CoA carboxylase in liver, and glycerol-3-phosphate acyltransferase in abdominal adipose tissue (P < 0.05). Microbiota analysis revealed that birds fed diets supplementation with 8 and 12% RS decreased the abundance of cecal Firmicutes by 23.08 and 20.47% and increased the proportion of Bacteroidetes by 24.33 and 21.92%, respectively, compared with the NC group (P < 0.05). In addition, correlation analysis revealed that many Firmicutes members had highly positive relationship with blood lipid levels and fat storage capacity, which might contribute to the lower abdominal fat phenotype. Overall, broilers receiving diets containing a higher concentration of RS harbor less Firmicutes, which decreased liver fatty acid synthesis and suppress abdominal fat deposition of birds during the starter phase. These findings provide a profound understanding about the relationship between gut microbial composition and lipid metabolism in broilers.

20.
Sci Rep ; 10(1): 18797, 2020 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-33139807

RESUMO

It is still debatable whether temperature or precipitation mainly triggers spring vegetation green-up (SVG) in alpine dry ecosystems on the Tibetan Plateau. As phenological sensitivity to the arrival of monsoon-season rainfall would allow plants to simultaneously avoid drought and frost damages in the early growing season, we hypothesize that rainy season onset (RSO) rather than temperature mainly drives the spatiotemporal variability of SVG across alpine dry ecosystems over the Tibetan Plateau. Dates of RSO and SVG across 67 target areas nearby 67 weather stations over the Tibetan Plateau were calculated from time-series data of daily mean temperature and precipitation (1974-2013) and of the Normalized Difference Vegetation Index from the Moderate Resolution Imaging Spectroradiometer (2001-2013), respectively. Satellite-derived SVG was validated by 7-year observations (2007-2013) for leaf emergence of dominant species in alpine meadows along elevations (4400-5200 m) in Damxung of Tibet. We found that SVG generally synchronized with or was somewhat later than RSO although seasonal air temperatures were already continuously above 0 °C in 1 month before SVG dates. In pooled data across sites and years, the analysis of linear mixed model indicated that RSO (F = 42.109) and its interactions with pre-SVG precipitation (F = 6.767) and temperature (F = 4.449) mainly explained the spatio-temporal variability of SVG, while pre-SVG temperature and its interaction with precipitation did not have significant effects on SVG. Our data supported the hypothesis, suggesting that synchronization of SVG and RSO is a general spring phenological strategy across alpine dry ecosystems under influence of monsoon climate.

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